WorldWideScience

Sample records for percent tree cover

  1. Modeling percent tree canopy cover: a pilot study

    Science.gov (United States)

    John W. Coulston; Gretchen G. Moisen; Barry T. Wilson; Mark V. Finco; Warren B. Cohen; C. Kenneth Brewer

    2012-01-01

    Tree canopy cover is a fundamental component of the landscape, and the amount of cover influences fire behavior, air pollution mitigation, and carbon storage. As such, efforts to empirically model percent tree canopy cover across the United States are a critical area of research. The 2001 national-scale canopy cover modeling and mapping effort was completed in 2006,...

  2. EnviroAtlas - Cleveland, OH - Estimated Percent Tree Cover Along Walkable Roads

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates tree cover along walkable roads. The road width is estimated for each road and percent tree cover is calculated in a 8.5 meter...

  3. EnviroAtlas - Austin, TX - Estimated Percent Tree Cover Along Walkable Roads

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates tree cover along walkable roads. The road width is estimated for each road and percent tree cover is calculated in a 8.5 meter...

  4. EnviroAtlas - Portland, ME - Estimated Percent Tree Cover Along Walkable Roads

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates tree cover along walkable roads. The road width is estimated for each road and percent tree cover is calculated in a 8.5 meter...

  5. EnviroAtlas - Woodbine, IA - Estimated Percent Tree Cover Along Walkable Roads

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates tree cover along walkable roads. The road width is estimated for each road and percent tree cover is calculated in a 8.5 meter...

  6. EnviroAtlas - Milwaukee, WI - Estimated Percent Tree Cover Along Walkable Roads

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates tree cover along walkable roads. The road width is estimated for each road and percent tree cover is calculated in a 8.5 meter...

  7. EnviroAtlas - Tampa, FL - Estimated Percent Tree Cover Along Walkable Roads

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates tree cover along walkable roads. The road width is estimated for each road and percent tree cover is calculated in a 8.5 meter...

  8. EnviroAtlas - Pittsburgh, PA - Estimated Percent Tree Cover Along Walkable Roads

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates tree cover along walkable roads. The road width is estimated for each road and percent tree cover is calculated in a 8.5 meter...

  9. EnviroAtlas - Phoenix, AZ - Estimated Percent Tree Cover Along Walkable Roads

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates tree cover along walkable roads. The road width is estimated for each road and percent tree cover is calculated in a 8.5 meter...

  10. EnviroAtlas - Durham, NC - Estimated Percent Tree Cover Along Walkable Roads

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates tree cover along walkable roads. The road width is estimated for each road and percent tree cover is calculated in a 8.5 meter...

  11. EnviroAtlas - Portland, OR - Estimated Percent Tree Cover Along Walkable Roads

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates tree cover along walkable roads. The road width is estimated for each road and percent tree cover is calculated in a 8.5 meter...

  12. EnviroAtlas - Paterson, NJ - Estimated Percent Tree Cover Along Walkable Roads

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates tree cover along walkable roads. The road width is estimated for each road and percent tree cover is calculated in a 8.5 meter...

  13. EnviroAtlas - Memphis, TN - Estimated Percent Tree Cover Along Walkable Roads

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates tree cover along walkable roads. The road width is estimated for each road and percent tree cover is calculated in a 8.5 meter...

  14. EnviroAtlas - Fresno, CA - Estimated Percent Tree Cover Along Walkable Roads

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates tree cover along walkable roads. The road width is estimated for each road and percent tree cover is calculated in a 8.5 meter...

  15. EnviroAtlas Estimated Percent Tree Cover Along Walkable Roads Web Service

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates tree cover along walkable roads. The road width is estimated for each road and percent tree cover is calculated in a 8.5 meter...

  16. EnviroAtlas - Des Moines, IA - Estimated Percent Tree Cover Along Walkable Roads

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates tree cover along walkable roads. The road width is estimated for each road and percent tree cover is calculated in a 8.5 meter...

  17. EnviroAtlas - Green Bay, WI - Estimated Percent Tree Cover Along Walkable Roads

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates tree cover along walkable roads. The road width is estimated for each road and percent tree cover is calculated in a 8.5 meter...

  18. EnviroAtlas - New York, NY - Estimated Percent Tree Cover Along Walkable Roads

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates tree cover along walkable roads. The road width is estimated for each road and percent tree cover is calculated in a 8.5 meter...

  19. EnviroAtlas - New Bedford, MA - Estimated Percent Tree Cover Along Walkable Roads

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates tree cover along walkable roads. The road width is estimated for each road and percent tree cover is calculated in a 8.5 meter...

  20. National Land Cover Database (NLCD) Percent Tree Canopy Collection

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The National Land Cover Database (NLCD) Percent Tree Canopy Collection is a product of the U.S. Forest Service (USFS), and is produced through a cooperative project...

  1. EnviroAtlas - Minneapolis/St. Paul, MN - Estimated Percent Tree Cover Along Walkable Roads

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates tree cover along walkable roads. The road width is estimated for each road and percent tree cover is calculated in a 8.5 meter...

  2. Estimation of Tree Cover in an Agricultural Parkland of Senegal Using Rule-Based Regression Tree Modeling

    Directory of Open Access Journals (Sweden)

    Stefanie M. Herrmann

    2013-10-01

    Full Text Available Field trees are an integral part of the farmed parkland landscape in West Africa and provide multiple benefits to the local environment and livelihoods. While field trees have received increasing interest in the context of strengthening resilience to climate variability and change, the actual extent of farmed parkland and spatial patterns of tree cover are largely unknown. We used the rule-based predictive modeling tool Cubist® to estimate field tree cover in the west-central agricultural region of Senegal. A collection of rules and associated multiple linear regression models was constructed from (1 a reference dataset of percent tree cover derived from very high spatial resolution data (2 m Orbview as the dependent variable, and (2 ten years of 10-day 250 m Moderate Resolution Imaging Spectrometer (MODIS Normalized Difference Vegetation Index (NDVI composites and derived phenological metrics as independent variables. Correlation coefficients between modeled and reference percent tree cover of 0.88 and 0.77 were achieved for training and validation data respectively, with absolute mean errors of 1.07 and 1.03 percent tree cover. The resulting map shows a west-east gradient from high tree cover in the peri-urban areas of horticulture and arboriculture to low tree cover in the more sparsely populated eastern part of the study area. A comparison of current (2000s tree cover along this gradient with historic cover as seen on Corona images reveals dynamics of change but also areas of remarkable stability of field tree cover since 1968. The proposed modeling approach can help to identify locations of high and low tree cover in dryland environments and guide ground studies and management interventions aimed at promoting the integration of field trees in agricultural systems.

  3. Quantifying environmental limiting factors on tree cover using geospatial data.

    Science.gov (United States)

    Greenberg, Jonathan A; Santos, Maria J; Dobrowski, Solomon Z; Vanderbilt, Vern C; Ustin, Susan L

    2015-01-01

    Environmental limiting factors (ELFs) are the thresholds that determine the maximum or minimum biological response for a given suite of environmental conditions. We asked the following questions: 1) Can we detect ELFs on percent tree cover across the eastern slopes of the Lake Tahoe Basin, NV? 2) How are the ELFs distributed spatially? 3) To what extent are unmeasured environmental factors limiting tree cover? ELFs are difficult to quantify as they require significant sample sizes. We addressed this by using geospatial data over a relatively large spatial extent, where the wall-to-wall sampling ensures the inclusion of rare data points which define the minimum or maximum response to environmental factors. We tested mean temperature, minimum temperature, potential evapotranspiration (PET) and PET minus precipitation (PET-P) as potential limiting factors on percent tree cover. We found that the study area showed system-wide limitations on tree cover, and each of the factors showed evidence of being limiting on tree cover. However, only 1.2% of the total area appeared to be limited by the four (4) environmental factors, suggesting other unmeasured factors are limiting much of the tree cover in the study area. Where sites were near their theoretical maximum, non-forest sites (tree cover demand, and closed-canopy forests were not limited by any particular environmental factor. The detection of ELFs is necessary in order to fully understand the width of limitations that species experience within their geographic range.

  4. Percent Wetland Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — Wetlands act as filters, removing or diminishing the amount of pollutants that enter surface water. Higher values for percent of wetland cover (WETLNDSPCT) may be...

  5. Quantifying environmental limiting factors on tree cover using geospatial data.

    Directory of Open Access Journals (Sweden)

    Jonathan A Greenberg

    Full Text Available Environmental limiting factors (ELFs are the thresholds that determine the maximum or minimum biological response for a given suite of environmental conditions. We asked the following questions: 1 Can we detect ELFs on percent tree cover across the eastern slopes of the Lake Tahoe Basin, NV? 2 How are the ELFs distributed spatially? 3 To what extent are unmeasured environmental factors limiting tree cover? ELFs are difficult to quantify as they require significant sample sizes. We addressed this by using geospatial data over a relatively large spatial extent, where the wall-to-wall sampling ensures the inclusion of rare data points which define the minimum or maximum response to environmental factors. We tested mean temperature, minimum temperature, potential evapotranspiration (PET and PET minus precipitation (PET-P as potential limiting factors on percent tree cover. We found that the study area showed system-wide limitations on tree cover, and each of the factors showed evidence of being limiting on tree cover. However, only 1.2% of the total area appeared to be limited by the four (4 environmental factors, suggesting other unmeasured factors are limiting much of the tree cover in the study area. Where sites were near their theoretical maximum, non-forest sites (tree cover < 25% were primarily limited by cold mean temperatures, open-canopy forest sites (tree cover between 25% and 60% were primarily limited by evaporative demand, and closed-canopy forests were not limited by any particular environmental factor. The detection of ELFs is necessary in order to fully understand the width of limitations that species experience within their geographic range.

  6. Percent Wetland Cover (Future)

    Data.gov (United States)

    U.S. Environmental Protection Agency — Wetlands act as filters, removing or diminishing the amount of pollutants that enter surface water. Higher values for percent of wetland cover (WETLNDSPCT) may be...

  7. Annual global tree cover estimated by fusing optical and SAR satellite observations

    Science.gov (United States)

    Feng, M.; Sexton, J. O.; Channan, S.; Townshend, J. R.

    2017-12-01

    Tree cover defined structurally as the proportional, vertically projected area of vegetation (including leaves, stems, branches, etc.) of woody plants above a given height affects terrestrial energy and water exchanges, photosynthesis and transpiration, net primary production, and carbon and nutrient fluxes. Tree cover provides a measurable attribute upon which forest cover may be defined. Changes in tree cover over time can be used to monitor and retrieve site-specific histories of forest disturbance, succession, and degradation. Measurements of Earth's tree cover have been produced at regional, national, and global extents. However, most representations are static, and those for which multiple time periods have been produced are neither intended nor adequate for consistent, long-term monitoring. Moreover, although a substantial proportion of change has been shown to occur at resolutions below 250 m, existing long-term, Landsat-resolution datasets are either produced as static layers or with annual, five- or ten-year temporal resolution. We have developed an algorithms to retrieve seamless and consistent, sub-hectare resolution estimates of tree-canopy from optical and radar satellite data sources (e.g., Landsat, Sentinel-2, and ALOS-PALSAR). Our approach to estimation enables assimilation of multiple data sources and produces estimates of both cover and its uncertainty at the scale of pixels. It has generated the world's first Landsat-based percent tree cover dataset in 2013. Our previous algorithms are being adapted to produce prototype percent-tree and water-cover layers globally in 2000, 2005, and 2010—as well as annually over North and South America from 2010 to 2015—from passive-optical (Landsat and Sentinel-2) and SAR measurements. Generating a global, annual dataset is beyond the scope of this support; however, North and South America represent all of the world's major biomes and so offer the complete global range of environmental sources of error and

  8. Comparing alternative tree canopy cover estimates derived from digital aerial photography and field-based assessments

    Science.gov (United States)

    Tracey S. Frescino; Gretchen G. Moisen

    2012-01-01

    A spatially-explicit representation of live tree canopy cover, such as the National Land Cover Dataset (NLCD) percent tree canopy cover layer, is a valuable tool for many applications, such as defining forest land, delineating wildlife habitat, estimating carbon, and modeling fire risk and behavior. These layers are generated by predictive models wherein their accuracy...

  9. Quantifying Environmental Limiting Factors on Tree Cover Using Geospatial Data

    NARCIS (Netherlands)

    Greenberg, Jonathan; Ferreira Dos Santos, Maria Joao; Dobrowski, Solomon; Vanderbilt, Vern; Ustin, Susan

    2015-01-01

    Environmental limiting factors (ELFs) are the thresholds that determine the maximum or minimum biological response for a given suite of environmental conditions. We asked the following questions: 1) Can we detect ELFs on percent tree cover across the eastern slopes of the Lake Tahoe Basin, NV? 2)

  10. Measuring and analyzing urban tree cover

    Science.gov (United States)

    David J. Nowak; Rowan A. Rowntree; E. Gregory McPherson; Susan M. Sisinni; Esther R. Kirkmann; Jack C. Stevens

    1996-01-01

    Measurement of city tree cover can aid in urban vegetation planning, management, and research by revealing characteristics of vegetation across a city. Urban tree cover in the United States ranges from 0.4% in Lancaster, California, to 55% in Baton Rouge, Louisiana. Two important factors that affect the amount of urban tree cover are the natural environment and land...

  11. Covering tree with stars

    DEFF Research Database (Denmark)

    Baumbach, Jan; Guo, Jian-Ying; Ibragimov, Rashid

    2013-01-01

    We study the tree edit distance problem with edge deletions and edge insertions as edit operations. We reformulate a special case of this problem as Covering Tree with Stars (CTS): given a tree T and a set of stars, can we connect the stars in by adding edges between them such that the resulting ...

  12. Covering tree with stars

    DEFF Research Database (Denmark)

    Baumbach, Jan; Guo, Jiong; Ibragimov, Rashid

    2015-01-01

    We study the tree edit distance problem with edge deletions and edge insertions as edit operations. We reformulate a special case of this problem as Covering Tree with Stars (CTS): given a tree T and a set of stars, can we connect the stars in by adding edges between them such that the resulting...... tree is isomorphic to T? We prove that in the general setting, CST is NP-complete, which implies that the tree edit distance considered here is also NP-hard, even when both input trees having diameters bounded by 10. We also show that, when the number of distinct stars is bounded by a constant k, CTS...

  13. Very High Resolution Tree Cover Mapping for Continental United States using Deep Convolutional Neural Networks

    Science.gov (United States)

    Ganguly, Sangram; Kalia, Subodh; Li, Shuang; Michaelis, Andrew; Nemani, Ramakrishna R.; Saatchi, Sassan A

    2017-01-01

    Uncertainties in input land cover estimates contribute to a significant bias in modeled above ground biomass (AGB) and carbon estimates from satellite-derived data. The resolution of most currently used passive remote sensing products is not sufficient to capture tree canopy cover of less than ca. 10-20 percent, limiting their utility to estimate canopy cover and AGB for trees outside of forest land. In our study, we created a first of its kind Continental United States (CONUS) tree cover map at a spatial resolution of 1-m for the 2010-2012 epoch using the USDA NAIP imagery to address the present uncertainties in AGB estimates. The process involves different tasks including data acquisition ingestion to pre-processing and running a state-of-art encoder-decoder based deep convolutional neural network (CNN) algorithm for automatically generating a tree non-tree map for almost a quarter million scenes. The entire processing chain including generation of the largest open source existing aerial satellite image training database was performed at the NEX supercomputing and storage facility. We believe the resulting forest cover product will substantially contribute to filling the gaps in ongoing carbon and ecological monitoring research and help quantifying the errors and uncertainties in derived products.

  14. Very High Resolution Tree Cover Mapping for Continental United States using Deep Convolutional Neural Networks

    Science.gov (United States)

    Ganguly, S.; Kalia, S.; Li, S.; Michaelis, A.; Nemani, R. R.; Saatchi, S.

    2017-12-01

    Uncertainties in input land cover estimates contribute to a significant bias in modeled above gound biomass (AGB) and carbon estimates from satellite-derived data. The resolution of most currently used passive remote sensing products is not sufficient to capture tree canopy cover of less than ca. 10-20 percent, limiting their utility to estimate canopy cover and AGB for trees outside of forest land. In our study, we created a first of its kind Continental United States (CONUS) tree cover map at a spatial resolution of 1-m for the 2010-2012 epoch using the USDA NAIP imagery to address the present uncertainties in AGB estimates. The process involves different tasks including data acquisition/ingestion to pre-processing and running a state-of-art encoder-decoder based deep convolutional neural network (CNN) algorithm for automatically generating a tree/non-tree map for almost a quarter million scenes. The entire processing chain including generation of the largest open source existing aerial/satellite image training database was performed at the NEX supercomputing and storage facility. We believe the resulting forest cover product will substantially contribute to filling the gaps in ongoing carbon and ecological monitoring research and help quantifying the errors and uncertainties in derived products.

  15. Carbon mapping of Argentine savannas: Using fractional tree cover to scale from field to region

    Science.gov (United States)

    González-Roglich, M.; Swenson, J. J.

    2015-12-01

    Programs which intend to maintain or enhance carbon (C) stocks in natural ecosystems are promising, but require detailed and spatially explicit C distribution models to monitor the effectiveness of management interventions. Savanna ecosystems are significant components of the global C cycle, covering about one fifth of the global land mass, but they have received less attention in C monitoring protocols. Our goal was to estimate C storage across a broad savanna ecosystem using field surveys and freely available satellite images. We first mapped tree canopies at 2.5 m resolution with a spatial subset of high resolution panchromatic images to then predict regional wall-to-wall tree percent cover using 30-m Landsat imagery and the Random Forests algorithms. We found that a model with summer and winter spectral indices from Landsat, climate and topography performed best. Using a linear relationship between C and % tree cover, we then predicted tree C stocks across the gradient of tree cover, explaining 87 % of the variability. The spatially explicit validation of the tree C model with field-measured C-stocks revealed an RMSE of 8.2 tC/ha which represented ~30% of the mean C stock for areas with tree cover, comparable to studies based on more advanced remote sensing methods, such as LiDAR and RADAR. Sample spatial distribution highly affected the performance of the RF models in predicting tree cover, raising concerns regarding the predictive capabilities of the model in areas for which training data is not present. The 50,000 km2 has ~41 Tg C, which could be released to the atmosphere if agricultural pressure intensifies in this semiarid savanna.

  16. Tree and impervious cover change in U.S

    Science.gov (United States)

    David J. Nowak; Eric J. Greenfield

    2012-01-01

    Paired aerial photographs were interpreted to assess recent changes in tree, impervious and other cover types in 20 U.S. cities as well as urban land within the conterminous United States. National results indicate that tree cover in urban areas of the United States is on the decline at a rate of about 7900 ha/yr or 4.0 million trees per year. Tree cover in 17 of the...

  17. Tree Cover Mapping Tool—Documentation and user manual

    Science.gov (United States)

    Cotillon, Suzanne E.; Mathis, Melissa L.

    2016-06-02

    The Tree Cover Mapping (TCM) tool was developed by scientists at the U.S. Geological Survey Earth Resources Observation and Science Center to allow a user to quickly map tree cover density over large areas using visual interpretation of high resolution imagery within a geographic information system interface. The TCM tool uses a systematic sample grid to produce maps of tree cover. The TCM tool allows the user to define sampling parameters to estimate tree cover within each sample unit. This mapping method generated the first on-farm tree cover maps of vast regions of Niger and Burkina Faso. The approach contributes to implementing integrated landscape management to scale up re-greening and restore degraded land in the drylands of Africa. The TCM tool is easy to operate, practical, and can be adapted to many other applications such as crop mapping, settlements mapping, or other features. This user manual provides step-by-step instructions for installing and using the tool, and creating tree cover maps. Familiarity with ArcMap tools and concepts is helpful for using the tool.

  18. A GIS-based tool for estimating tree canopy cover on fixed-radius plots using high-resolution aerial imagery

    Science.gov (United States)

    Sara A. Goeking; Greg C. Liknes; Erik Lindblom; John Chase; Dennis M. Jacobs; Robert. Benton

    2012-01-01

    Recent changes to the Forest Inventory and Analysis (FIA) Program's definition of forest land precipitated the development of a geographic information system (GIS)-based tool for efficiently estimating tree canopy cover for all FIA plots. The FIA definition of forest land has shifted from a density-related criterion based on stocking to a 10 percent tree canopy...

  19. Soil cover by natural trees in agroforestry systems

    Science.gov (United States)

    Diaz-Ambrona, C. G. H.; Almoguera Millán, C.; Tarquis Alfonso, A.

    2009-04-01

    The dehesa is common agroforestry system in the Iberian Peninsula. These open oak parklands with silvo-pastoral use cover about two million hectares. Traditionally annual pastures have been grazed by cows, sheep and also goats while acorns feed Iberian pig diet. Evergreen oak (Quercus ilex L.) has other uses as fuelwood collection and folder after tree pruning. The hypothesis of this work is that tree density and canopy depend on soil types. We using the spanish GIS called SIGPAC to download the images of dehesa in areas with different soil types. True colour images were restoring to a binary code, previously canopy colour range was selected. Soil cover by tree canopy was calculated and number of trees. Processing result was comparable to real data. With these data we have applied a dynamic simulation model Dehesa to determine evergreen oak acorn and annual pasture production. The model Dehesa is divided into five submodels: Climate, Soil, Evergreen oak, Pasture and Grazing. The first three require the inputs: (i) daily weather data (maximum and minimum temperatures, precipitation and solar radiation); (ii) the soil input parameters for three horizons (thickness, field capacity, permanent wilting point, and bulk density); and (iii) the tree characterization of the dehesa (tree density, canopy diameter and height, and diameter of the trunk). The influence of tree on pasture potential production is inversely proportional to the canopy cover. Acorn production increase with tree canopy cover until stabilizing itself, and will decrease if density becomes too high (more than 80% soil tree cover) at that point there is competition between the trees. Main driving force for dehesa productivity is soil type for pasture, and tree cover for acorn production. Highest pasture productivity was obtained on soil Dystric Planosol (Alfisol), Dystric Cambisol and Chromo-calcic-luvisol, these soils only cover 22.4% of southwest of the Iberian peninssula. Lowest productivity was

  20. National Land Cover Database (NLCD) Percent Developed Imperviousness Collection

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The National Land Cover Database (NLCD) Percent Developed Imperviousness Collection is produced through a cooperative project conducted by the Multi-Resolution Land...

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

    Science.gov (United States)

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

    2017-12-01

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

  2. Calibration and Validation of Landsat Tree Cover in the Taiga−Tundra Ecotone

    Directory of Open Access Journals (Sweden)

    Paul Mannix Montesano

    2016-06-01

    Full Text Available Monitoring current forest characteristics in the taiga−tundra ecotone (TTE at multiple scales is critical for understanding its vulnerability to structural changes. A 30 m spatial resolution Landsat-based tree canopy cover map has been calibrated and validated in the TTE with reference tree cover data from airborne LiDAR and high resolution spaceborne images across the full range of boreal forest tree cover. This domain-specific calibration model used estimates of forest height to determine reference forest cover that best matched Landsat estimates. The model removed the systematic under-estimation of tree canopy cover >80% and indicated that Landsat estimates of tree canopy cover more closely matched canopies at least 2 m in height rather than 5 m. The validation improved estimates of uncertainty in tree canopy cover in discontinuous TTE forests for three temporal epochs (2000, 2005, and 2010 by reducing systematic errors, leading to increases in tree canopy cover uncertainty. Average pixel-level uncertainties in tree canopy cover were 29.0%, 27.1% and 31.1% for the 2000, 2005 and 2010 epochs, respectively. Maps from these calibrated data improve the uncertainty associated with Landsat tree canopy cover estimates in the discontinuous forests of the circumpolar TTE.

  3. Comprehensive monitoring of Bangladesh tree cover inside and outside of forests, 2000-2014

    Science.gov (United States)

    Potapov, P.; Siddiqui, B. N.; Iqbal, Z.; Aziz, T.; Zzaman, B.; Islam, A.; Pickens, A.; Talero, Y.; Tyukavina, A.; Turubanova, S.; Hansen, M. C.

    2017-10-01

    A novel approach for satellite-based comprehensive national tree cover change assessment was developed and applied in Bangladesh, a country where trees outside of forests play an important role in the national economy and carbon sequestration. Tree cover change area was quantified using the integration of wall-to-wall Landsat-based mapping with a higher spatial resolution sample-based assessment. The total national tree canopy cover area was estimated as 3165 500 ± 186 600 ha in the year 2000, with trees outside forests making up 54% of total canopy cover. Total tree canopy cover increased by 135 700 (± 116 600) ha (4.3%) during the 2000-2014 time interval. Bangladesh exhibits a national tree cover dynamic where net change is rather small, but gross dynamics significant and variable by forest type. Despite the overall gain in tree cover, results revealed the ongoing clearing of natural forests, especially within the Chittagong hill tracts. While forests decreased their tree cover area by 83 600 ha, the trees outside forests (including tree plantations, village woodlots, and agroforestry) increased their canopy area by 219 300 ha. Our results demonstrated method capability to quantify tree canopy cover dynamics within a fine-scale agricultural landscape. Our approach for comprehensive monitoring of tree canopy cover may be recommended for operational implementation in Bangladesh and other countries with significant tree cover outside of forests.

  4. Los Angeles 1-Million tree canopy cover assessment

    Science.gov (United States)

    Gregory E. McPherson; James R. Simpson; Qingfu Xiao; Wu Chunxia

    2008-01-01

    The Million Trees LA initiative intends to chart a course for sustainable growth through planting and stewardship of trees. The purpose of this study was to measure Los Angeles's existing tree canopy cover (TCC), determine if space exists for 1 million additional trees, and estimate future benefits from the planting. High resolution QuickBird remote sensing data,...

  5. Rapid assessment and mapping of tree cover in southern African savanna woodlands using a new iPhone App and Landsat 8 imagery

    Science.gov (United States)

    Fuller, D. O.

    2016-12-01

    Tree cover is a key parameter in climate modeling. It strongly influences CO2 exchanges between the land surface and atmosphere and surface energy balance. We measured percent woody canopy cover (PWCC) in the savanna woodlands of eastern Zambia over a 10-day period in May 2016 using a new iPhone App (CanopyApp) and related these field measurements to Landsat 8 (L8) Band 4 (red) imagery acquired approximately the same time. We then used parameters from the band 4 digital numbers (DNs)-PWCC linear regression to derive a new map of PWCC for the entire L8 scene. Consistent with theory and previous empirical studies, we found that the relationship between L8 band 4 DNs- PWCC was negative and linear (r2 = 0.61, p reflectance was weaker (r2 = 0.46, p shadowing effects and other spatial inhomogeneities from variable soil and background reflectance. Our PWCC map agreed qualitatively with similar percent tree-cover maps based on Landsat level 1 products and past field studies in the area conducted using a hemispherical lens. Our results also compared favorably with other remote sensing studies that have used complex multivariate approaches to estimate tree cover, which suggests that use of a single L8 band 4 is sufficient to estimate PWCC when spectral contrast exists between the grass, soil and tree layers during the austral fall period in southern African savannas.

  6. Permafrost thaw and wildfire: Equally important drivers of boreal tree cover changes in the Taiga Plains, Canada

    Science.gov (United States)

    Helbig, M.; Pappas, C.; Sonnentag, O.

    2016-02-01

    Boreal forests cover vast areas of the permafrost zones of North America, and changes in their composition and structure can lead to pronounced impacts on the regional and global climate. We partition the variation in regional boreal tree cover changes between 2000 and 2014 across the Taiga Plains, Canada, into its main causes: permafrost thaw, wildfire disturbance, and postfire regrowth. Moderate Resolution Imaging Spectroradiometer Percent Tree Cover (PTC) data are used in combination with maps of historic fires, and permafrost and drainage characteristics. We find that permafrost thaw is equally important as fire history to explain PTC changes. At the southern margin of the permafrost zone, PTC loss due to permafrost thaw outweighs PTC gain from postfire regrowth. These findings emphasize the importance of permafrost thaw in controlling regional boreal forest changes over the last decade, which may become more pronounced with rising air temperatures and accelerated permafrost thaw.

  7. DeepSAT: A Deep Learning Approach to Tree-Cover Delineation in 1-m NAIP Imagery for the Continental United States

    Science.gov (United States)

    Ganguly, Sangram; Basu, Saikat; Nemani, Ramakrishna R.; Mukhopadhyay, Supratik; Michaelis, Andrew; Votava, Petr

    2016-01-01

    state of California spanning a total of 11,095 NAIP tiles covering a total geographical area of 163,696 sq. miles has produced true positive rates of around 88 percent for fragmented forests and 74 percent for urban tree cover areas, with false positive rates lower than 2 percent for both landscapes.

  8. Recent tree cover increases in eastern China linked to low, declining human pressure, steep topography, and climatic conditions favoring tree growth.

    Directory of Open Access Journals (Sweden)

    Jonas Nüchel

    Full Text Available Globally, the extent of forest continues to decline, however, some countries have increased their forest extent in recent years. China is one of these countries and has managed to increase their tree cover through huge reforestation and afforestation programs during recent decades as well as land abandonment dynamics. This study investigates tree cover change in the eastern half of China between 2000 and 2010 on three different scales, using random forest modeling of remote sensing data for tree cover in relation to environmental and anthropogenic predictor variables. Our results show that between the years 2000 and 2010 2,667,875 km2 experienced an increase in tree cover while 1,854,900 km2 experienced a decline in tree cover. The area experiencing ≥10% increase in tree cover is almost twice as large as the area with ≥10% drop in tree cover. There is a clear relation between topography and tree cover change with steeper and mid-elevation areas having a larger response on tree cover increase than other areas. Furthermore, human influence, change in population density, and actual evapotranspiration are also important factors in explaining where tree cover has changed. This study adds to the understanding of tree cover change in China, as it has focus on the entire eastern half of China on three different scales and how tree cover change is linked to topography and anthropogenic pressure. Though, our results show an increase in tree cover in China, this study emphasizes the importance of incorporating anthropogenic factors together with biodiversity protection into the reforestation and afforestation programs in the future.

  9. Recent tree cover increases in eastern China linked to low, declining human pressure, steep topography, and climatic conditions favoring tree growth.

    Science.gov (United States)

    Nüchel, Jonas; Svenning, Jens-Christian

    2017-01-01

    Globally, the extent of forest continues to decline, however, some countries have increased their forest extent in recent years. China is one of these countries and has managed to increase their tree cover through huge reforestation and afforestation programs during recent decades as well as land abandonment dynamics. This study investigates tree cover change in the eastern half of China between 2000 and 2010 on three different scales, using random forest modeling of remote sensing data for tree cover in relation to environmental and anthropogenic predictor variables. Our results show that between the years 2000 and 2010 2,667,875 km2 experienced an increase in tree cover while 1,854,900 km2 experienced a decline in tree cover. The area experiencing ≥10% increase in tree cover is almost twice as large as the area with ≥10% drop in tree cover. There is a clear relation between topography and tree cover change with steeper and mid-elevation areas having a larger response on tree cover increase than other areas. Furthermore, human influence, change in population density, and actual evapotranspiration are also important factors in explaining where tree cover has changed. This study adds to the understanding of tree cover change in China, as it has focus on the entire eastern half of China on three different scales and how tree cover change is linked to topography and anthropogenic pressure. Though, our results show an increase in tree cover in China, this study emphasizes the importance of incorporating anthropogenic factors together with biodiversity protection into the reforestation and afforestation programs in the future.

  10. Tree cover changes in- and ouside protected areas in China

    DEFF Research Database (Denmark)

    Nüchel, Jonas; Bøcher, Peder Klith; Svenning, J.-C.

    Protected areas (PAs) are one of the main tools in the global conservation of biodiversity and ecosystems. This is also the case for China. However, only few studies have investigated protected areas´ efficiency in maintaining ecosystems and biodiversity. One way to investigate this is to look...... at tree cover changes inside the PAs and on the surrounding areas. Using MODIS Vegetation Continuous Fields we mapped tree-cover changes between 2000-2010 in- and outside PAs in China. The PAs were extracted from the World Database on Protected Areas. Our aim were to investigated the following four...... between tree cover change and general human pressure. We did not find a significant correlation between tree cover change inside and outside PAs with increasing general human pressures. The lack of correlation could be due to the huge reforestation China has carried out the last years, mainly to stop...

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

    Directory of Open Access Journals (Sweden)

    Carlos Augusto Zangrando Toneli

    2011-09-01

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

  12. Trees grow on money: Urban tree canopy cover and environmental justice

    Science.gov (United States)

    Kirsten Schwarz; Michail Fragkias; Christopher G. Boone; Weiqi Zhou; Melissa McHale; J. Morgan Grove; Jarlath O' Neil-Dunne; Joseph P. McFadden; Geoffrey L. Buckley; Dan Childers; Laura Ogden; Stephanie Pincetl; Diane Pataki; Ali Whitmer; Mary L. Cadenasso; Steven Arthur. Loiselle

    2015-01-01

    This study examines the distributional equity of urban tree canopy (UTC) cover for Baltimore, MD, Los Angeles, CA, New York, NY, Philadelphia, PA, Raleigh, NC, Sacramento, CA, and Washington, D.C. using high spatial resolution land cover data and census data. Data are analyzed at the Census Block Group levels using Spearman’s correlation, ordinary least squares...

  13. Million trees Los Angeles canopy cover and benefit assessment

    Science.gov (United States)

    E.G. McPherson; J.R. Simpson; Q. Xiao; C. Wu

    2011-01-01

    The Million Trees LA initiative intends to improve Los Angeles’s environment through planting and stewardship of 1 million trees. The purpose of this study was to measure Los Angeles’s existing tree canopy cover (TCC), determine if space exists for 1 million additional trees, and estimate future benefits from the planting. High-resolution QuickBird remote sensing data...

  14. Object-Based Mapping of the Circumpolar Taiga-Tundra Ecotone with MODIS Tree Cover

    Science.gov (United States)

    Ranson, K. J.; Montesano, P. M.; Nelson, R.

    2011-01-01

    The circumpolar taiga tundra ecotone was delineated using an image-segmentation-based mapping approach with multi-annual MODIS Vegetation Continuous Fields (VCF) tree cover data. Circumpolar tree canopy cover (TCC) throughout the ecotone was derived by averaging MODIS VCF data from 2000 to 2005 and adjusting the averaged values using linear equations relating MODIS TCC to Quickbird-derived tree cover estimates. The adjustment helped mitigate VCF's overestimation of tree cover in lightly forested regions. An image segmentation procedure was used to group pixels representing similar tree cover into polygonal features (segmentation objects) that form the map of the transition zone. Each polygon represents an area much larger than the 500 m MODIS pixel and characterizes the patterns of sparse forest patches on a regional scale. Those polygons near the boreal/tundra interface with either (1) mean adjusted TCC values from5 to 20%, or (2) mean adjusted TCC values greater than 5% but with a standard deviation less than 5% were used to identify the ecotone. Comparisons of the adjusted average tree cover data were made with (1) two existing tree line definitions aggregated for each 1 degree longitudinal interval in North America and Eurasia, (2) Landsat-derived Canadian proportion of forest cover for Canada, and (3) with canopy cover estimates extracted from airborne profiling lidar data that transected 1238 of the TCC polygons. The adjusted TCC from MODIS VCF shows, on average, less than 12% TCC for all but one regional zone at the intersection with independently delineated tree lines. Adjusted values track closely with Canadian proportion of forest cover data in areas of low tree cover. A comparison of the 1238 TCC polygons with profiling lidar measurements yielded an overall accuracy of 67.7%.

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

    DEFF Research Database (Denmark)

    Asare, Richard; Ræbild, Anders

    2016-01-01

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

  16. Diseases of Ornamental and Shade Trees, Shrubs, Vines, and Ground Covers.

    Science.gov (United States)

    Nichols, Lester P.

    This agriculture extension service publication from Pennsylvania State University covers the identification and control of common ornamental trees, shrubs, and ground cover diseases. The publication is divided into sections. The first section discusses the diseases of ornamental and shade trees, including general diseases and diseases of specific…

  17. Percent Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — Forests provide economic and ecological value. High percentages of forest cover (FORPCT) generally indicate healthier ecosystems and cleaner surface water. More...

  18. Declining urban and community tree cover in the United States

    Science.gov (United States)

    David J. Nowak; Eric J. Greenfield

    2018-01-01

    Paired aerial photographs were interpreted to assess recent changes (c. 2009–2014) in tree, impervious and other cover types within urban/community and urban land in all 50 United States and the District of Columbia. National results indicate that tree cover in urban/community areas of the United States is on the decline at a rate of about 175,000 acres per year, which...

  19. Intermediate tree cover can maximize groundwater recharge in the seasonally dry tropics

    Science.gov (United States)

    Ilstedt, U.; Bargués Tobella, A.; Bazié, H. R.; Bayala, J.; Verbeeten, E.; Nyberg, G.; Sanou, J.; Benegas, L.; Murdiyarso, D.; Laudon, H.; Sheil, D.; Malmer, A.

    2016-01-01

    Water scarcity contributes to the poverty of around one-third of the world’s people. Despite many benefits, tree planting in dry regions is often discouraged by concerns that trees reduce water availability. Yet relevant studies from the tropics are scarce, and the impacts of intermediate tree cover remain unexplored. We developed and tested an optimum tree cover theory in which groundwater recharge is maximized at an intermediate tree density. Below this optimal tree density the benefits from any additional trees on water percolation exceed their extra water use, leading to increased groundwater recharge, while above the optimum the opposite occurs. Our results, based on groundwater budgets calibrated with measurements of drainage and transpiration in a cultivated woodland in West Africa, demonstrate that groundwater recharge was maximised at intermediate tree densities. In contrast to the prevailing view, we therefore find that moderate tree cover can increase groundwater recharge, and that tree planting and various tree management options can improve groundwater resources. We evaluate the necessary conditions for these results to hold and suggest that they are likely to be common in the seasonally dry tropics, offering potential for widespread tree establishment and increased benefits for hundreds of millions of people. PMID:26908158

  20. The influence of multi-season imagery on models of canopy cover: A case study

    Science.gov (United States)

    John W. Coulston; Dennis M. Jacobs; Chris R. King; Ivey C. Elmore

    2013-01-01

    Quantifying tree canopy cover in a spatially explicit fashion is important for broad-scale monitoring of ecosystems and for management of natural resources. Researchers have developed empirical models of tree canopy cover to produce geospatial products. For subpixel models, percent tree canopy cover estimates (derived from fine-scale imagery) serve as the response...

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

    Science.gov (United States)

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

    2016-06-01

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

  2. Ecosystem services from converted land: the importance of tree cover in Amazonian pastures

    Science.gov (United States)

    Barrett, Kirsten; Valentim, Judson; Turner, B. L.

    2013-01-01

    Deforestation is responsible for a substantial fraction of global carbon emissions and changes in surface energy budgets that affect climate. Deforestation losses include wildlife and human habitat, and myriad forest products on which rural and urban societies depend for food, fiber, fuel, fresh water, medicine, and recreation. Ecosystem services gained in the transition from forests to pasture and croplands, however, are often ignored in assessments of the impact of land cover change. The role of converted lands in tropical areas in terms of carbon uptake and storage is largely unknown. Pastures represent the fastest-growing form of converted land use in the tropics, even in some areas of rapid urban expansion. Tree biomass stored in these areas spans a broad range, depending on tree cover. Trees in pasture increase carbon storage, provide shade for cattle, and increase productivity of forage material. As a result, increasing fractional tree cover can provide benefits land managers as well as important ecosystem services such as reducing conversion pressure on forests adjacent to pastures. This study presents an estimation of fractional tree cover in pasture in a dynamic region on the verge of large-scale land use change. An appropriate sampling interval is established for similar studies, one that balances the need for independent samples of sufficient number to characterize a pasture in terms of fractional tree cover. This information represents a useful policy tool for government organizations and NGOs interested in encouraging ecosystem services on converted lands. Using high spatial resolution remotely sensed imagery, fractional tree cover in pasture is quantified for the municipality of Rio Branco, Brazil. A semivariogram and devolving spatial resolution are employed to determine the coarsest sampling interval that may be used, minimizing effects of spatial autocorrelation. The coarsest sampling interval that minimizes spatial dependence was about 22 m. The

  3. Tree cover in Central Africa: determinants and sensitivity under contrasted scenarios of global change.

    Science.gov (United States)

    Aleman, Julie C; Blarquez, Olivier; Gourlet-Fleury, Sylvie; Bremond, Laurent; Favier, Charly

    2017-01-30

    Tree cover is a key variable for ecosystem functioning, and is widely used to study tropical ecosystems. But its determinants and their relative importance are still a matter of debate, especially because most regional and global analyses have not considered the influence of agricultural practices. More information is urgently needed regarding how human practices influence vegetation structure. Here we focused in Central Africa, a region still subjected to traditional agricultural practices with a clear vegetation gradient. Using remote sensing data and global databases, we calibrated a Random Forest model to correlatively link tree cover with climatic, edaphic, fire and agricultural practices data. We showed that annual rainfall and accumulated water deficit were the main drivers of the distribution of tree cover and vegetation classes (defined by the modes of tree cover density), but agricultural practices, especially pastoralism, were also important in determining tree cover. We simulated future tree cover with our model using different scenarios of climate and land-use (agriculture and population) changes. Our simulations suggest that tree cover may respond differently regarding the type of scenarios, but land-use change was an important driver of vegetation change even able to counterbalance the effect of climate change in Central Africa.

  4. Tree cover and species composition effects on academic performance of primary school students.

    Science.gov (United States)

    Sivarajah, Sivajanani; Smith, Sandy M; Thomas, Sean C

    2018-01-01

    Human exposure to green space and vegetation is widely recognized to result in physical and mental health benefits; however, to date, the specific effects of tree cover, diversity, and species composition on student academic performance have not been investigated. We compiled standardized performance scores in Grades 3 and 6 for the collective student body in 387 schools across the Toronto District School Board (TDSB), and examined variation in relation to tree cover, tree diversity, and tree species composition based on comprehensive inventories of trees on school properties combined with aerial-photo-based assessments of tree cover. Analyses accounted for variation due to socioeconomic factors using the learning opportunity index (LOI), a regional composite index of external challenges to learning that incorporates income and other factors, such as students with English as a second language. As expected, LOI had the greatest influence on student academic performance; however, the proportion of tree cover, as distinct from other types of "green space" such as grass, was found to be a significant positive predictor of student performance, accounting for 13% of the variance explained in a statistical model predicting mean student performance assessments. The effects of tree cover and species composition were most pronounced in schools that showed the highest level of external challenges, suggesting the importance of urban forestry investments in these schools.

  5. Field performance of alternative landfill covers vegetated with cottonwood and eucalyptus trees.

    Science.gov (United States)

    Abichou, Tarek; Musagasa, Jubily; Yuan, Lei; Chanton, Jeff; Tawfiq, Kamal; Rockwood, Donald; Licht, Louis

    2012-01-01

    A field study was conducted to assess the ability of landfill covers to control percolation into the waste. Performance of one conventional cover was compared to that of two evapotranspiration (ET) tree covers, using large (7 x 14 m) lined lysimeters at the Leon County Solid Waste management facility in Tallahassee, Florida. Additional unlined test sections were also constructed and monitored in order to compare soil water storage, soil temperature, and tree growth inside lysimeters and in unlined test sections. The unlined test sections were in direct contact with landfill gas. Surface runoff on the ET covers was a small proportion of the water balance (1% of precipitation) as compared to 13% in the conventional cover. Percolation in the ET covers averaged 17% and 24% of precipitation as compared to 33% in the conventional cover. On average, soil water storage was higher in the lined lysimeters (429 mm) compared to unlined test sections (408 mm). The average soil temperature in the lysimeters was lower than in the unlined test sections. The average tree height inside the lysimeters was not significantly lower (8.04 mfor eucalyptus and 7.11 mfor cottonwood) than outside (8.82 m for eucalyptus and 8.01 m for cottonwood). ET tree covers vegetated with cottonwood or eucalyptus are feasible for North Florida climate as an alternative to GCL covers.

  6. The average covering tree value for directed graph games

    NARCIS (Netherlands)

    Khmelnitskaya, Anna Borisovna; Selcuk, Özer; Talman, Dolf

    We introduce a single-valued solution concept, the so-called average covering tree value, for the class of transferable utility games with limited communication structure represented by a directed graph. The solution is the average of the marginal contribution vectors corresponding to all covering

  7. A global reference database from very high resolution commercial satellite data and methodology for application to Landsat derived 30 m continuous field tree cover data

    Science.gov (United States)

    Pengra, Bruce; Long, Jordan; Dahal, Devendra; Stehman, Stephen V.; Loveland, Thomas R.

    2015-01-01

    The methodology for selection, creation, and application of a global remote sensing validation dataset using high resolution commercial satellite data is presented. High resolution data are obtained for a stratified random sample of 500 primary sampling units (5 km  ×  5 km sample blocks), where the stratification based on Köppen climate classes is used to distribute the sample globally among biomes. The high resolution data are classified to categorical land cover maps using an analyst mediated classification workflow. Our initial application of these data is to evaluate a global 30 m Landsat-derived, continuous field tree cover product. For this application, the categorical reference classification produced at 2 m resolution is converted to percent tree cover per 30 m pixel (secondary sampling unit)for comparison to Landsat-derived estimates of tree cover. We provide example results (based on a subsample of 25 sample blocks in South America) illustrating basic analyses of agreement that can be produced from these reference data. Commercial high resolution data availability and data quality are shown to provide a viable means of validating continuous field tree cover. When completed, the reference classifications for the full sample of 500 blocks will be released for public use.

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

    Directory of Open Access Journals (Sweden)

    J. A. Ejares

    2016-06-01

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

  9. Tree cover, tree height and bare soil cover differences along a land use degradation gradient in semi-arid savannas, South Africa

    CSIR Research Space (South Africa)

    Mathieu, R

    2009-07-01

    Full Text Available High resolution airborne hyperspectral and discrete return LiDAR data were used to assess bare soil and tree cover differences along a land use transect consisting of state-owned, privately-owned conservation areas, and communal areas in South...

  10. Percent Forest Cover (Future)

    Data.gov (United States)

    U.S. Environmental Protection Agency — Forests provide economic and ecological value. High percentages of forest cover (FORPCTFuture) generally indicate healthier ecosystems and cleaner surface water....

  11. Urban trees and forests of the Chicago region

    Science.gov (United States)

    David J. Nowak; Robert E. III Hoehn; Allison R. Bodine; Daniel E. Crane; John F. Dwyer; Veta Bonnewell; Gary Watson

    2013-01-01

    An analysis of trees in the Chicago region of Illinois reveals that this area has about 157,142,000 trees with tree and shrub canopy that covers 21.0 percent of the region. The most common tree species are European buckthorn, green ash, boxelder, black cherry, and American elm. Trees in the Chicago region currently store about 16.9 million tons of carbon (61.9 million...

  12. Tree cover in sub-Saharan Africa: rainfall and fire constrain forest and savanna as alternative stable states

    CSIR Research Space (South Africa)

    Staver, AC

    2011-01-01

    Full Text Available Savannas are known as ecosystems with tree cover below climate-defined equilibrium values. However, a predictive framework for understanding constraints on tree cover is lacking. The authors present a) a spatially extensive analysis of tree cover...

  13. Response of Boreal forest tree canopy cover to chronic gamma irradiation

    International Nuclear Information System (INIS)

    Amiro, B.D.

    1994-01-01

    A section of the Canadian Boreal forest was irradiated chronically by a point source of 137 Cs from 1973 to 1986. Tree canopy cover was measured at permanently marked locations during the pre-irradiation, irradiation and post-irradiation phases, spanning a period of two decades. The tree canopy was severely affected at dose rates greater than 10 mGy/h delivered chronically. The canopy of sensitive coniferous tree species, such as Abies balsamea and Picea Mariana, decreased at dose rates greater than 2 mGy/h, but in some cases the tree canopy was replaced by more resistant species, such as Populus tremuloides and Salix bebbiana. Effects on canopy cover could not be detected at dose rates less than 0.1 mGy/h. Even at dose rates of 5 mGy/h, the forest canopy is recovering six years after irradiation stopped. (author)

  14. Percent of Impervious Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — High amounts of impervious cover (parking lots, rooftops, roads, etc.) can increase water runoff, which may directly enter surface water. Runoff from roads often...

  15. MODIS Snow Cover Mapping Decision Tree Technique: Snow and Cloud Discrimination

    Science.gov (United States)

    Riggs, George A.; Hall, Dorothy K.

    2010-01-01

    Accurate mapping of snow cover continues to challenge cryospheric scientists and modelers. The Moderate-Resolution Imaging Spectroradiometer (MODIS) snow data products have been used since 2000 by many investigators to map and monitor snow cover extent for various applications. Users have reported on the utility of the products and also on problems encountered. Three problems or hindrances in the use of the MODIS snow data products that have been reported in the literature are: cloud obscuration, snow/cloud confusion, and snow omission errors in thin or sparse snow cover conditions. Implementation of the MODIS snow algorithm in a decision tree technique using surface reflectance input to mitigate those problems is being investigated. The objective of this work is to use a decision tree structure for the snow algorithm. This should alleviate snow/cloud confusion and omission errors and provide a snow map with classes that convey information on how snow was detected, e.g. snow under clear sky, snow tinder cloud, to enable users' flexibility in interpreting and deriving a snow map. Results of a snow cover decision tree algorithm are compared to the standard MODIS snow map and found to exhibit improved ability to alleviate snow/cloud confusion in some situations allowing up to about 5% increase in mapped snow cover extent, thus accuracy, in some scenes.

  16. Projecting range-wide sun bear population trends using tree cover and camera-trap bycatch data.

    Directory of Open Access Journals (Sweden)

    Lorraine Scotson

    Full Text Available Monitoring population trends of threatened species requires standardized techniques that can be applied over broad areas and repeated through time. Sun bears Helarctos malayanus are a forest dependent tropical bear found throughout most of Southeast Asia. Previous estimates of global population trends have relied on expert opinion and cannot be systematically replicated. We combined data from 1,463 camera traps within 31 field sites across sun bear range to model the relationship between photo catch rates of sun bears and tree cover. Sun bears were detected in all levels of tree cover above 20%, and the probability of presence was positively associated with the amount of tree cover within a 6-km2 buffer of the camera traps. We used the relationship between catch rates and tree cover across space to infer temporal trends in sun bear abundance in response to tree cover loss at country and global-scales. Our model-based projections based on this "space for time" substitution suggested that sun bear population declines associated with tree cover loss between 2000-2014 in mainland southeast Asia were ~9%, with declines highest in Cambodia and lowest in Myanmar. During the same period, sun bear populations in insular southeast Asia (Malaysia, Indonesia and Brunei were projected to have declined at a much higher rate (22%. Cast forward over 30-years, from the year 2000, by assuming a constant rate of change in tree cover, we projected population declines in the insular region that surpassed 50%, meeting the IUCN criteria for endangered if sun bears were listed on the population level. Although this approach requires several assumptions, most notably that trends in abundance across space can be used to infer temporal trends, population projections using remotely sensed tree cover data may serve as a useful alternative (or supplement to expert opinion. The advantages of this approach is that it is objective, data-driven, repeatable, and it requires that

  17. Effects of interannual climate variability on tropical tree cover

    NARCIS (Netherlands)

    Holmgren, M.; Hirota, M.; Nes, van E.H.; Scheffer, M.

    2013-01-01

    Climatic warming is substantially intensifying the global water cycle1 and is projected to increase rainfall variability2. Using satellite data, we show that higher climatic variability is associated with reduced tree cover in the wet tropics globally. In contrast, interannual variability in

  18. The National Land Cover Database

    Science.gov (United States)

    Homer, Collin G.; Fry, Joyce A.; Barnes, Christopher A.

    2012-01-01

    The National Land Cover Database (NLCD) serves as the definitive Landsat-based, 30-meter resolution, land cover database for the Nation. NLCD provides spatial reference and descriptive data for characteristics of the land surface such as thematic class (for example, urban, agriculture, and forest), percent impervious surface, and percent tree canopy cover. NLCD supports a wide variety of Federal, State, local, and nongovernmental applications that seek to assess ecosystem status and health, understand the spatial patterns of biodiversity, predict effects of climate change, and develop land management policy. NLCD products are created by the Multi-Resolution Land Characteristics (MRLC) Consortium, a partnership of Federal agencies led by the U.S. Geological Survey. All NLCD data products are available for download at no charge to the public from the MRLC Web site: http://www.mrlc.gov.

  19. The Average Covering Tree Value for Directed Graph Games

    NARCIS (Netherlands)

    Khmelnitskaya, A.; Selcuk, O.; Talman, A.J.J.

    2012-01-01

    Abstract: We introduce a single-valued solution concept, the so-called average covering tree value, for the class of transferable utility games with limited communication structure represented by a directed graph. The solution is the average of the marginal contribution vectors corresponding to all

  20. Cover of tall trees best predicts California spotted owl habitat

    Science.gov (United States)

    Malcolm P. North; Jonathan T. Kane; Van R. Kane; Gregory P. Asner; William Berigan; Derek J. Churchill; Scott Conway; R.J. Gutiérrez; Sean Jeronimo; John Keane; Alexander Koltunov; Tina Mark; Monika Moskal; Thomas Munton; Zachary Peery; Carlos Ramirez; Rahel Sollmann; Angela White; Sheila Whitmore

    2017-01-01

    Restoration of western dry forests in the USA often focuses on reducing fuel loads. In the range of the spotted owl, these treatments may reduce canopy cover and tree density, which could reduce preferred habitat conditions for the owl and other sensitive species. In particular, high canopy cover (≥70%) has been widely reported to be an important feature of spotted owl...

  1. Complex Relationships of the Effects of Topographic Characteristics and Susceptible Tree Cover on Burn Severity

    Directory of Open Access Journals (Sweden)

    Hyun-Joo Lee

    2018-01-01

    Full Text Available Forest fires and burn severity mosaics have profound impacts on the post-fire dynamics and complexity of forest ecosystems. Numerous studies have investigated the relationship between topographic variables and susceptible tree covers with regard to burn severity. However, these relationships have not been fully elucidated, because most studies have assumed linearity in these relationships. Therefore, we examined the linearity and the nonlinearity in the relationships between topographic variables and susceptible tree covers with burn severity by comparing linear and nonlinear models. The site of the Samcheok fire, the largest recorded forest fire in Korea, was used as the study area. We generated 802 grid cells with a 500-m resolution that encompassed the entire study area and collected a dataset that included the topographic variables and percentage of red pine trees, which are the most susceptible tree cover types in Korea. We used conventional linear models and generalized additive models to estimate the linear and the nonlinear models based on topographic variables and Japanese red pine trees. The results revealed that the percentage of red pine trees had linear effects on burn severity, reinforcing the importance of silviculture and forest management to lower burn severity. Meanwhile, the topographic variables had nonlinear effects on burn severity. Among the topographic variables, elevation had the strongest nonlinear effect on burn severity, possibly by overriding the effects of susceptible fuels over elevation effects or due to the nonlinear effects of topographic characteristics on pre-fire fuel conditions, including the spatial distribution and availability of susceptible tree cover. To validate and generalize the nonlinear effects of elevation and other topographic variables, additional research is required at different fire sites with different tree cover types in different geographic locations.

  2. Effects of shrub and tree cover increase on the near-surface atmosphere in northern Fennoscandia

    Directory of Open Access Journals (Sweden)

    J. H. Rydsaa

    2017-09-01

    Full Text Available Increased shrub and tree cover in high latitudes is a widely observed response to climate change that can lead to positive feedbacks to the regional climate. In this study we evaluate the sensitivity of the near-surface atmosphere to a potential increase in shrub and tree cover in the northern Fennoscandia region. We have applied the Weather Research and Forecasting (WRF model with the Noah-UA land surface module in evaluating biophysical effects of increased shrub cover on the near-surface atmosphere at a fine resolution (5.4 km  ×  5.4 km. Perturbation experiments are performed in which we prescribe a gradual increase in taller vegetation in the alpine shrub and tree cover according to empirically established bioclimatic zones within the study region. We focus on the spring and summer atmospheric response. To evaluate the sensitivity of the atmospheric response to inter-annual variability in climate, simulations were conducted for two contrasting years, one warm and one cold. We find that shrub and tree cover increase leads to a general increase in near-surface temperatures, with the highest influence seen during the snowmelt season and a more moderate effect during summer. We find that the warming effect is stronger in taller vegetation types, with more complex canopies leading to decreases in the surface albedo. Counteracting effects include increased evapotranspiration, which can lead to increased cloud cover, precipitation, and snow cover. We find that the strength of the atmospheric feedback is sensitive to snow cover variations and to a lesser extent to summer temperatures. Our results show that the positive feedback to high-latitude warming induced by increased shrub and tree cover is a robust feature across inter-annual differences in meteorological conditions and will likely play an important role in land–atmosphere feedback processes in the future.

  3. Land-use change outweighs projected effects of changing rainfall on tree cover in sub-Saharan Africa.

    Science.gov (United States)

    Aleman, Julie C; Blarquez, Olivier; Staver, Carla A

    2016-09-01

    Global change will likely affect savanna and forest structure and distributions, with implications for diversity within both biomes. Few studies have examined the impacts of both expected precipitation and land use changes on vegetation structure in the future, despite their likely severity. Here, we modeled tree cover in sub-Saharan Africa, as a proxy for vegetation structure and land cover change, using climatic, edaphic, and anthropic data (R(2)  = 0.97). Projected tree cover for the year 2070, simulated using scenarios that include climate and land use projections, generally decreased, both in forest and savanna, although the directionality of changes varied locally. The main driver of tree cover changes was land use change; the effects of precipitation change were minor by comparison. Interestingly, carbon emissions mitigation via increasing biofuels production resulted in decreases in tree cover, more severe than scenarios with more intense precipitation change, especially within savannas. Evaluation of tree cover change against protected area extent at the WWF Ecoregion scale suggested areas of high biodiversity and ecosystem services concern. Those forests most vulnerable to large decreases in tree cover were also highly protected, potentially buffering the effects of global change. Meanwhile, savannas, especially where they immediately bordered forests (e.g. West and Central Africa), were characterized by a dearth of protected areas, making them highly vulnerable. Savanna must become an explicit policy priority in the face of climate and land use change if conservation and livelihoods are to remain viable into the next century. © 2016 John Wiley & Sons Ltd.

  4. Estimating tree species diversity in the savannah using NDVI and woody canopy cover

    Science.gov (United States)

    Madonsela, Sabelo; Cho, Moses Azong; Ramoelo, Abel; Mutanga, Onisimo; Naidoo, Laven

    2018-04-01

    Remote sensing applications in biodiversity research often rely on the establishment of relationships between spectral information from the image and tree species diversity measured in the field. Most studies have used normalized difference vegetation index (NDVI) to estimate tree species diversity on the basis that it is sensitive to primary productivity which defines spatial variation in plant diversity. The NDVI signal is influenced by photosynthetically active vegetation which, in the savannah, includes woody canopy foliage and grasses. The question is whether the relationship between NDVI and tree species diversity in the savanna depends on the woody cover percentage. This study explored the relationship between woody canopy cover (WCC) and tree species diversity in the savannah woodland of southern Africa and also investigated whether there is a significant interaction between seasonal NDVI and WCC in the factorial model when estimating tree species diversity. To fulfil our aim, we followed stratified random sampling approach and surveyed tree species in 68 plots of 90 m × 90 m across the study area. Within each plot, all trees with diameter at breast height of >10 cm were sampled and Shannon index - a common measure of species diversity which considers both species richness and abundance - was used to quantify tree species diversity. We then extracted WCC in each plot from existing fractional woody cover product produced from Synthetic Aperture Radar (SAR) data. Factorial regression model was used to determine the interaction effect between NDVI and WCC when estimating tree species diversity. Results from regression analysis showed that (i) WCC has a highly significant relationship with tree species diversity (r2 = 0.21; p NDVI and WCC is not significant, however, the factorial model significantly reduced the error of prediction (RMSE = 0.47, p NDVI (RMSE = 0.49) or WCC (RMSE = 0.49) model during the senescence period. The result justifies our assertion

  5. EnviroAtlas - Tampa, FL - Tree Cover Configuration and Connectivity, Water Background

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset categorizes forest land cover into structural elements (e.g. core, edge, connector, etc.). In this community, forest is trees & forest...

  6. EnviroAtlas - Woodbine, IA - Tree Cover Configuration and Connectivity, Water Background

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset categorizes forest land cover into structural elements (e.g. core, edge, connector, etc.). In this community, forest is only trees &...

  7. EnviroAtlas - Durham, NC - Tree Cover Configuration and Connectivity, Water Background

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset categorizes forest land cover into structural elements (e.g. core, edge, connector, etc.). In this community, forest is only trees &...

  8. EnviroAtlas - Fresno, CA - Tree Cover Configuration and Connectivity, Water Background

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset categorizes forest land cover into structural elements (e.g. core, edge, connector, etc.). In this community, forest is only trees &...

  9. EnviroAtlas - Portland, OR - Tree Cover Configuration and Connectivity, Water Background

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset categorizes forest land cover into structural elements (e.g. core, edge, connector, etc.). In this community, forest is trees & forest...

  10. Analysis of effects of manhole covers on motorcycle driver maneuvers: a nonparametric classification tree approach.

    Science.gov (United States)

    Chang, Li-Yen

    2014-01-01

    A manhole cover is a removable plate forming the lid over the opening of a manhole to allow traffic to pass over the manhole and to prevent people from falling in. Because most manhole covers are placed in roadway traffic lanes, if these manhole covers are not appropriately installed or maintained, they can represent unexpected hazards on the road, especially for motorcycle drivers. The objective of this study is to identify the effects of manhole cover characteristics as well as driver factors and traffic and roadway conditions on motorcycle driver maneuvers. A video camera was used to record motorcycle drivers' maneuvers when they encountered an inappropriately installed or maintained manhole cover. Information on 3059 drivers' maneuver decisions was recorded. Classification and regression tree (CART) models were applied to explore factors that can significantly affect motorcycle driver maneuvers when passing a manhole cover. Nearly 50 percent of the motorcycle drivers decelerated or changed their driving path to reduce the effects of the manhole cover. The manhole cover characteristics including the level difference between manhole cover and pavement, the pavement condition over the manhole cover, and the size of the manhole cover can significantly affect motorcycle driver maneuvers. Other factors, including traffic conditions, lane width, motorcycle speed, and loading conditions, also have significant effects on motorcycle driver maneuvers. To reduce the effects and potential risks from the manhole covers, highway authorities not only need to make sure that any newly installed manhole covers are as level as possible but also need to regularly maintain all the manhole covers to ensure that they are in good condition. In the long run, the size of manhole covers should be kept as small as possible so that the impact of manhole covers on motorcycle drivers can be effectively reduced. Supplemental materials are available for this article. Go to the publisher

  11. Database for estimating tree responses of walnut and other hardwoods to ground cover management practices

    Science.gov (United States)

    J.W. Van Sambeek

    2010-01-01

    The ground cover in plantings of walnut and other hardwoods can substantially affect tree growth and seed production. The number of alternative ground covers that have been suggested for establishment in tree plantings far exceeds the number that have already been tested with walnut and other temperate hardwoods. Knowing how other hardwood species respond to ground...

  12. EnviroAtlas - Minneapolis/St. Paul, MN - Tree Cover Configuration and Connectivity

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset categorizes forest land cover into structural elements (e.g. core, edge, connector, etc.). In this community, forest is defined as Trees...

  13. EnviroAtlas - Memphis, TN - Tree Cover Configuration and Connectivity, Water Background

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset categorizes forest land cover into structural elements (e.g. core, edge, connector, etc.). Forest is defined as Trees & Forest and Woody...

  14. EnviroAtlas - Austin, TX - Tree Cover Configuration and Connectivity, Water Background

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset categorizes forest land cover into structural elements (e.g. core, edge, connector, etc.). In this community, Forest is defined as Trees...

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

    International Nuclear Information System (INIS)

    Hassan, N

    2014-01-01

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

  16. CMS: LiDAR-derived Tree Canopy Cover for Pennsylvania, USA, 2008

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set provides estimated high-resolution (1-m) tree canopy cover for the state of Pennsylvania, USA, in 2008. The data were derived from 2006-2008...

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

    International Nuclear Information System (INIS)

    Hassan, N

    2014-01-01

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

  18. EnviroAtlas - Green Bay, WI - Tree Cover Configuration and Connectivity, Water Background

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset categorizes forest land cover into structural elements (e.g. core, edge, connector, etc.). In this community, forest is trees & forest...

  19. EnviroAtlas - Des Moines, IA - Tree Cover Configuration and Connectivity, Water Background

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset categorizes forest land cover into structural elements (e.g. core, edge, connector, etc.). In this community, Forest is defined as Trees...

  20. Reduction of tree cover in West African woodlands and promotion in semi-arid farmlands

    Science.gov (United States)

    Brandt, Martin; Rasmussen, Kjeld; Hiernaux, Pierre; Herrmann, Stefanie; Tucker, Compton J.; Tong, Xiaoye; Tian, Feng; Mertz, Ole; Kergoat, Laurent; Mbow, Cheikh; David, John L.; Melocik, Katherine A.; Dendoncker, Morgane; Vincke, Caroline; Fensholt, Rasmus

    2018-05-01

    Woody vegetation in farmland acts as a carbon sink and provides ecosystem services for local people, but no macroscale assessments of the impact of management and climate on woody cover exist for drylands. Here we make use of very high spatial resolution satellite imagery to derive wall-to-wall woody cover patterns in tropical West African drylands. Our study reveals that mean woody cover in farmlands along all semi-arid and sub-humid rainfall zones is 16%, on average only 6% lower than in savannahs. In semi-arid Sahel, farmland management promotes woody cover around villages (11%), while neighbouring savannahs had on average less woody cover. However, farmlands in sub-humid zones have a greatly reduced woody cover (21%) as compared with savannahs (33%). In the region as a whole, rainfall, terrain and soil are the most important (80%) determinants of woody cover, while management factors play a smaller (20%) role. We conclude that agricultural expansion causes a considerable reduction of trees in woodlands, but observations in Sahel indicate that villagers safeguard trees on nearby farmlands which contradicts simplistic ideas of a high negative correlation between population density and woody cover.

  1. Evaluating the relationship between biomass, percent groundcover and remote sensing indices across six winter cover crop fields in Maryland, United States

    Science.gov (United States)

    Prabhakara, Kusuma; Hively, W. Dean; McCarty, Gregory W.

    2015-07-01

    Winter cover crops are an essential part of managing nutrient and sediment losses from agricultural lands. Cover crops lessen sedimentation by reducing erosion, and the accumulation of nitrogen in aboveground biomass results in reduced nutrient runoff. Winter cover crops are planted in the fall and are usually terminated in early spring, making them susceptible to senescence, frost burn, and leaf yellowing due to wintertime conditions. This study sought to determine to what extent remote sensing indices are capable of accurately estimating the percent groundcover and biomass of winter cover crops, and to analyze under what critical ranges these relationships are strong and under which conditions they break down. Cover crop growth on six fields planted to barley, rye, ryegrass, triticale or wheat was measured over the 2012-2013 winter growing season. Data collection included spectral reflectance measurements, aboveground biomass, and percent groundcover. Ten vegetation indices were evaluated using surface reflectance data from a 16-band CROPSCAN sensor. Restricting analysis to sampling dates before the onset of prolonged freezing temperatures and leaf yellowing resulted in increased estimation accuracy. There was a strong relationship between the normalized difference vegetation index (NDVI) and percent groundcover (r2 = 0.93) suggesting that date restrictions effectively eliminate yellowing vegetation from analysis. The triangular vegetation index (TVI) was most accurate in estimating high ranges of biomass (r2 = 0.86), while NDVI did not experience a clustering of values in the low and medium biomass ranges but saturated in the higher range (>1500 kg/ha). The results of this study show that accounting for index saturation, senescence, and frost burn on leaves can greatly increase the accuracy of estimates of percent groundcover and biomass for winter cover crops.

  2. Tree cover and aridity projections to 2060: a technical document supporting the Forest Service 2010 RPA assessment

    Science.gov (United States)

    Eric J. Greenfield; David J. Nowak

    2013-01-01

    Future projections of tree cover and climate change are useful to natural resource managers as they illustrate potential changes to our natural resources and the ecosystem services they provide. This report a) details three projections of tree cover change across the conterminous United States based on predicted land-use changes from 2000 to 2060; b) evaluates nine...

  3. Large-Area, High-Resolution Tree Cover Mapping with Multi-Temporal SPOT5 Imagery, New South Wales, Australia

    Directory of Open Access Journals (Sweden)

    Adrian Fisher

    2016-06-01

    Full Text Available Tree cover maps are used for many purposes, such as vegetation mapping, habitat connectivity and fragmentation studies. Small remnant patches of native vegetation are recognised as ecologically important, yet they are underestimated in remote sensing products derived from Landsat. High spatial resolution sensors are capable of mapping small patches of trees, but their use in large-area mapping has been limited. In this study, multi-temporal Satellite pour l’Observation de la Terre 5 (SPOT5 High Resolution Geometrical data was pan-sharpened to 5 m resolution and used to map tree cover for the Australian state of New South Wales (NSW, an area of over 800,000 km2. Complete coverages of SPOT5 panchromatic and multispectral data over NSW were acquired during four consecutive summers (2008–2011 for a total of 1256 images. After pre-processing, the imagery was used to model foliage projective cover (FPC, a measure of tree canopy density commonly used in Australia. The multi-temporal imagery, FPC models and 26,579 training pixels were used in a binomial logistic regression model to estimate the probability of each pixel containing trees. The probability images were classified into a binary map of tree cover using local thresholds, and then visually edited to reduce errors. The final tree map was then attributed with the mean FPC value from the multi-temporal imagery. Validation of the binary map based on visually assessed high resolution reference imagery revealed an overall accuracy of 88% (±0.51% standard error, while comparison against airborne lidar derived data also resulted in an overall accuracy of 88%. A preliminary assessment of the FPC map by comparing against 76 field measurements showed a very good agreement (r2 = 0.90 with a root mean square error of 8.57%, although this may not be representative due to the opportunistic sampling design. The map represents a regionally consistent and locally relevant record of tree cover for NSW, and

  4. EnviroAtlas - Percent Land Cover with Potentially Restorable Wetlands on Agricultural Land per 12-Digit HUC - Contiguous United States

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset shows the percent land cover with potentially restorable wetlands on agricultural land for each 12-digit Hydrologic Unit (HUC) watershed in...

  5. The value of urban tree cover: A hedonic property price model in Ramsey and Dakota Counties, Minnesota, USA

    Science.gov (United States)

    Heather Sander; Stephen Polasky; Robert. Haight

    2010-01-01

    Urban tree cover benefits communities. These benefits' economic values, however, are poorly recognized and often ignored by landowners and planners. We use hedonic property price modeling to estimate urban tree cover's value in Dakota and Ramsey Counties, MN, USA, predicting housing value as a function of structural, neighborhood, and environmental variables...

  6. Accuracy assessment of the vegetation continuous field tree cover product using 3954 ground plots in the southwestern USA

    Science.gov (United States)

    M. A. White; J. D. Shaw; R. D. Ramsey

    2005-01-01

    An accuracy assessment of the Moderate Resolution Imaging Spectroradiometer (MODIS) vegetation continuous field (VCF) tree cover product using two independent ground-based tree cover databases was conducted. Ground data included 1176 Forest Inventory and Analysis (FIA) plots for Arizona and 2778 Southwest Regional GAP (SWReGAP) plots for Utah and western Colorado....

  7. Integrating Landsat Data and High-Resolution Imagery for Applied Conservation Assessment of Forest Cover in Latin American Heterogenous Landscapes

    Science.gov (United States)

    Thomas, N.; Rueda, X.; Lambin, E.; Mendenhall, C. D.

    2012-12-01

    Large intact forested regions of the world are known to be critical to maintaining Earth's climate, ecosystem health, and human livelihoods. Remote sensing has been successfully implemented as a tool to monitor forest cover and landscape dynamics over broad regions. Much of this work has been done using coarse resolution sensors such as AVHRR and MODIS in combination with moderate resolution sensors, particularly Landsat. Finer scale analysis of heterogeneous and fragmented landscapes is commonly performed with medium resolution data and has had varying success depending on many factors including the level of fragmentation, variability of land cover types, patch size, and image availability. Fine scale tree cover in mixed agricultural areas can have a major impact on biodiversity and ecosystem sustainability but may often be inadequately captured with the global to regional (coarse resolution and moderate resolution) satellite sensors and processing techniques widely used to detect land use and land cover changes. This study investigates whether advanced remote sensing methods are able to assess and monitor percent tree canopy cover in spatially complex human-dominated agricultural landscapes that prove challenging for traditional mapping techniques. Our study areas are in high altitude, mixed agricultural coffee-growing regions in Costa Rica and the Colombian Andes. We applied Random Forests regression tree analysis to Landsat data along with additional spectral, environmental, and spatial variables to predict percent tree canopy cover at 30m resolution. Image object-based texture, shape, and neighborhood metrics were generated at the Landsat scale using eCognition and included in the variable suite. Training and validation data was generated using high resolution imagery from digital aerial photography at 1m to 2.5 m resolution. Our results are promising with Pearson's correlation coefficients between observed and predicted percent tree canopy cover of .86 (Costa

  8. Cheatgrass percent cover change: Comparing recent estimates to climate change − Driven predictions in the Northern Great Basin

    Science.gov (United States)

    Boyte, Stephen P.; Wylie, Bruce K.; Major, Donald J.

    2016-01-01

    Cheatgrass (Bromus tectorum L.) is a highly invasive species in the Northern Great Basin that helps decrease fire return intervals. Fire fragments the shrub steppe and reduces its capacity to provide forage for livestock and wildlife and habitat critical to sagebrush obligates. Of particular interest is the greater sage grouse (Centrocercus urophasianus), an obligate whose populations have declined so severely due, in part, to increases in cheatgrass and fires that it was considered for inclusion as an endangered species. Remote sensing technologies and satellite archives help scientists monitor terrestrial vegetation globally, including cheatgrass in the Northern Great Basin. Along with geospatial analysis and advanced spatial modeling, these data and technologies can identify areas susceptible to increased cheatgrass cover and compare these with greater sage grouse priority areas for conservation (PAC). Future climate models forecast a warmer and wetter climate for the Northern Great Basin, which likely will force changing cheatgrass dynamics. Therefore, we examine potential climate-caused changes to cheatgrass. Our results indicate that future cheatgrass percent cover will remain stable over more than 80% of the study area when compared with recent estimates, and higher overall cheatgrass cover will occur with slightly more spatial variability. The land area projected to increase or decrease in cheatgrass cover equals 18% and 1%, respectively, making an increase in fire disturbances in greater sage grouse habitat likely. Relative susceptibility measures, created by integrating cheatgrass percent cover and temporal standard deviation datasets, show that potential increases in future cheatgrass cover match future projections. This discovery indicates that some greater sage grouse PACs for conservation could be at heightened risk of fire disturbance. Multiple factors will affect future cheatgrass cover including changes in precipitation timing and totals and

  9. Decision Tree and Texture Analysis for Mapping Debris-Covered Glaciers in the Kangchenjunga Area, Eastern Himalaya

    Directory of Open Access Journals (Sweden)

    Adina Racoviteanu

    2012-10-01

    Full Text Available In this study we use visible, short-wave infrared and thermal Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER data validated with high-resolution Quickbird (QB and Worldview2 (WV2 for mapping debris cover in the eastern Himalaya using two independent approaches: (a a decision tree algorithm, and (b texture analysis. The decision tree algorithm was based on multi-spectral and topographic variables, such as band ratios, surface reflectance, kinetic temperature from ASTER bands 10 and 12, slope angle, and elevation. The decision tree algorithm resulted in 64 km2 classified as debris-covered ice, which represents 11% of the glacierized area. Overall, for ten glacier tongues in the Kangchenjunga area, there was an area difference of 16.2 km2 (25% between the ASTER and the QB areas, with mapping errors mainly due to clouds and shadows. Texture analysis techniques included co-occurrence measures, geostatistics and filtering in spatial/frequency domain. Debris cover had the highest variance of all terrain classes, highest entropy and lowest homogeneity compared to the other classes, for example a mean variance of 15.27 compared to 0 for clouds and 0.06 for clean ice. Results of the texture image for debris-covered areas were comparable with those from the decision tree algorithm, with 8% area difference between the two techniques.

  10. Global Tree Cover and Biomass Carbon on Agricultural Land: The contribution of agroforestry to global and national carbon budgets.

    Science.gov (United States)

    Zomer, Robert J; Neufeldt, Henry; Xu, Jianchu; Ahrends, Antje; Bossio, Deborah; Trabucco, Antonio; van Noordwijk, Meine; Wang, Mingcheng

    2016-07-20

    Agroforestry systems and tree cover on agricultural land make an important contribution to climate change mitigation, but are not systematically accounted for in either global carbon budgets or national carbon accounting. This paper assesses the role of trees on agricultural land and their significance for carbon sequestration at a global level, along with recent change trends. Remote sensing data show that in 2010, 43% of all agricultural land globally had at least 10% tree cover and that this has increased by 2% over the previous ten years. Combining geographically and bioclimatically stratified Intergovernmental Panel on Climate Change (IPCC) Tier 1 default estimates of carbon storage with this tree cover analysis, we estimated 45.3 PgC on agricultural land globally, with trees contributing >75%. Between 2000 and 2010 tree cover increased by 3.7%, resulting in an increase of >2 PgC (or 4.6%) of biomass carbon. On average, globally, biomass carbon increased from 20.4 to 21.4 tC ha(-1). Regional and country-level variation in stocks and trends were mapped and tabulated globally, and for all countries. Brazil, Indonesia, China and India had the largest increases in biomass carbon stored on agricultural land, while Argentina, Myanmar, and Sierra Leone had the largest decreases.

  11. Sustaining America's urban trees and forests: a Forests on the Edge report

    Science.gov (United States)

    David J. Nowak; Paula B. Randler; Eric J. Greenfield; Sara J. Comas; Mary A. Carr; Ralph J. Alig

    2010-01-01

    Close to 80 percent of the U.S. population lives in urban areas and depends on the essential ecological, economic, and social benefits provided by urban trees and forests. However, the distribution of urban tree cover and the benefits of urban forests vary across the United States, as do the challenges of sustaining this important resource. As urban areas expand...

  12. Assessing alternative measures of tree canopy cover: Photo-interpreted NAIP and ground-based estimates

    Science.gov (United States)

    Chris Toney; Greg Liknes; Andy Lister; Dacia Meneguzzo

    2012-01-01

    In preparation for the development of the National Land Cover Database (NLCD) 2011 tree canopy cover layer, a pilot project for research and method development was completed in 2010 by the USDA Forest Service Forest Inventory and Analysis (FIA) program and Remote Sensing Applications Center (RSAC).This paper explores one of several topics investigated during the NLCD...

  13. Cacao Cultivation under Diverse Shade Tree Cover Allows High Carbon Storage and Sequestration without Yield Losses.

    Science.gov (United States)

    Abou Rajab, Yasmin; Leuschner, Christoph; Barus, Henry; Tjoa, Aiyen; Hertel, Dietrich

    2016-01-01

    One of the main drivers of tropical forest loss is their conversion to oil palm, soy or cacao plantations with low biodiversity and greatly reduced carbon storage. Southeast Asian cacao plantations are often established under shade tree cover, but are later converted to non-shaded monocultures to avoid resource competition. We compared three co-occurring cacao cultivation systems (3 replicate stands each) with different shade intensity (non-shaded monoculture, cacao with the legume Gliricidia sepium shade trees, and cacao with several shade tree species) in Sulawesi (Indonesia) with respect to above- and belowground biomass and productivity, and cacao bean yield. Total biomass C stocks (above- and belowground) increased fivefold from the monoculture to the multi-shade tree system (from 11 to 57 Mg ha-1), total net primary production rose twofold (from 9 to 18 Mg C ha-1 yr-1). This increase was associated with a 6fold increase in aboveground biomass, but only a 3.5fold increase in root biomass, indicating a clear shift in C allocation to aboveground tree organs with increasing shade for both cacao and shade trees. Despite a canopy cover increase from 50 to 93%, cacao bean yield remained invariant across the systems (variation: 1.1-1.2 Mg C ha-1 yr-1). The monocultures had a twice as rapid leaf turnover suggesting that shading reduces the exposure of cacao to atmospheric drought, probably resulting in greater leaf longevity. Thus, contrary to general belief, cacao bean yield does not necessarily decrease under shading which seems to reduce physical stress. If planned properly, cacao plantations under a shade tree cover allow combining high yield with benefits for carbon sequestration and storage, production system stability under stress, and higher levels of animal and plant diversity.

  14. A High Performance Computing Approach to Tree Cover Delineation in 1-m NAIP Imagery Using a Probabilistic Learning Framework

    Science.gov (United States)

    Basu, Saikat; Ganguly, Sangram; Michaelis, Andrew; Votava, Petr; Roy, Anshuman; Mukhopadhyay, Supratik; Nemani, Ramakrishna

    2015-01-01

    Tree cover delineation is a useful instrument in deriving Above Ground Biomass (AGB) density estimates from Very High Resolution (VHR) airborne imagery data. Numerous algorithms have been designed to address this problem, but most of them do not scale to these datasets, which are of the order of terabytes. In this paper, we present a semi-automated probabilistic framework for the segmentation and classification of 1-m National Agriculture Imagery Program (NAIP) for tree-cover delineation for the whole of Continental United States, using a High Performance Computing Architecture. Classification is performed using a multi-layer Feedforward Backpropagation Neural Network and segmentation is performed using a Statistical Region Merging algorithm. The results from the classification and segmentation algorithms are then consolidated into a structured prediction framework using a discriminative undirected probabilistic graphical model based on Conditional Random Field, which helps in capturing the higher order contextual dependencies between neighboring pixels. Once the final probability maps are generated, the framework is updated and re-trained by relabeling misclassified image patches. This leads to a significant improvement in the true positive rates and reduction in false positive rates. The tree cover maps were generated for the whole state of California, spanning a total of 11,095 NAIP tiles covering a total geographical area of 163,696 sq. miles. The framework produced true positive rates of around 88% for fragmented forests and 74% for urban tree cover areas, with false positive rates lower than 2% for both landscapes. Comparative studies with the National Land Cover Data (NLCD) algorithm and the LiDAR canopy height model (CHM) showed the effectiveness of our framework for generating accurate high-resolution tree-cover maps.

  15. A High Performance Computing Approach to Tree Cover Delineation in 1-m NAIP Imagery using a Probabilistic Learning Framework

    Science.gov (United States)

    Basu, S.; Ganguly, S.; Michaelis, A.; Votava, P.; Roy, A.; Mukhopadhyay, S.; Nemani, R. R.

    2015-12-01

    Tree cover delineation is a useful instrument in deriving Above Ground Biomass (AGB) density estimates from Very High Resolution (VHR) airborne imagery data. Numerous algorithms have been designed to address this problem, but most of them do not scale to these datasets which are of the order of terabytes. In this paper, we present a semi-automated probabilistic framework for the segmentation and classification of 1-m National Agriculture Imagery Program (NAIP) for tree-cover delineation for the whole of Continental United States, using a High Performance Computing Architecture. Classification is performed using a multi-layer Feedforward Backpropagation Neural Network and segmentation is performed using a Statistical Region Merging algorithm. The results from the classification and segmentation algorithms are then consolidated into a structured prediction framework using a discriminative undirected probabilistic graphical model based on Conditional Random Field, which helps in capturing the higher order contextual dependencies between neighboring pixels. Once the final probability maps are generated, the framework is updated and re-trained by relabeling misclassified image patches. This leads to a significant improvement in the true positive rates and reduction in false positive rates. The tree cover maps were generated for the whole state of California, spanning a total of 11,095 NAIP tiles covering a total geographical area of 163,696 sq. miles. The framework produced true positive rates of around 88% for fragmented forests and 74% for urban tree cover areas, with false positive rates lower than 2% for both landscapes. Comparative studies with the National Land Cover Data (NLCD) algorithm and the LiDAR canopy height model (CHM) showed the effectiveness of our framework for generating accurate high-resolution tree-cover maps.

  16. Large-scale biotic interaction effects - tree cover interacts with shade toler-ance to affect distribution patterns of herb and shrub species across the Alps

    DEFF Research Database (Denmark)

    Nieto-Lugilde, Diego; Lenoir, Jonathan; Abdulhak, Sylvain

    2012-01-01

    on the occurrence on light-demanding species via size-asymmetric competition for light, but a facilitative effect on shade-tolerant species. In order to compare the relative importance of tree cover, four models with different combinations of variables (climate, soil and tree cover) were run for each species. Then...... role. Results indicated that high tree cover causes range contraction, especially at the upper limit, for light-demanding species, whereas it causes shade-tolerant species to extend their range upwards and downwards. Tree cover thus drives plant-plant interactions to shape plant species distribution...

  17. A stepwise regression tree for nonlinear approximation: applications to estimating subpixel land cover

    Science.gov (United States)

    Huang, C.; Townshend, J.R.G.

    2003-01-01

    A stepwise regression tree (SRT) algorithm was developed for approximating complex nonlinear relationships. Based on the regression tree of Breiman et al . (BRT) and a stepwise linear regression (SLR) method, this algorithm represents an improvement over SLR in that it can approximate nonlinear relationships and over BRT in that it gives more realistic predictions. The applicability of this method to estimating subpixel forest was demonstrated using three test data sets, on all of which it gave more accurate predictions than SLR and BRT. SRT also generated more compact trees and performed better than or at least as well as BRT at all 10 equal forest proportion interval ranging from 0 to 100%. This method is appealing to estimating subpixel land cover over large areas.

  18. A Semi-Automated Machine Learning Algorithm for Tree Cover Delineation from 1-m Naip Imagery Using a High Performance Computing Architecture

    Science.gov (United States)

    Basu, S.; Ganguly, S.; Nemani, R. R.; Mukhopadhyay, S.; Milesi, C.; Votava, P.; Michaelis, A.; Zhang, G.; Cook, B. D.; Saatchi, S. S.; Boyda, E.

    2014-12-01

    Accurate tree cover delineation is a useful instrument in the derivation of Above Ground Biomass (AGB) density estimates from Very High Resolution (VHR) satellite imagery data. Numerous algorithms have been designed to perform tree cover delineation in high to coarse resolution satellite imagery, but most of them do not scale to terabytes of data, typical in these VHR datasets. In this paper, we present an automated probabilistic framework for the segmentation and classification of 1-m VHR data as obtained from the National Agriculture Imagery Program (NAIP) for deriving tree cover estimates for the whole of Continental United States, using a High Performance Computing Architecture. The results from the classification and segmentation algorithms are then consolidated into a structured prediction framework using a discriminative undirected probabilistic graphical model based on Conditional Random Field (CRF), which helps in capturing the higher order contextual dependencies between neighboring pixels. Once the final probability maps are generated, the framework is updated and re-trained by incorporating expert knowledge through the relabeling of misclassified image patches. This leads to a significant improvement in the true positive rates and reduction in false positive rates. The tree cover maps were generated for the state of California, which covers a total of 11,095 NAIP tiles and spans a total geographical area of 163,696 sq. miles. Our framework produced correct detection rates of around 85% for fragmented forests and 70% for urban tree cover areas, with false positive rates lower than 3% for both regions. Comparative studies with the National Land Cover Data (NLCD) algorithm and the LiDAR high-resolution canopy height model shows the effectiveness of our algorithm in generating accurate high-resolution tree cover maps.

  19. SAFARI 2000 Tree Cover from AVHRR, 1-km, 1992-1993 (DeFries et al.)

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set consists of a southern African subset of the 1-km Global Tree Cover Data Set developed at the Laboratory for Global Remote Sensing Studies...

  20. SAFARI 2000 Tree Cover from AVHRR, 1-km, 1992-1993 (DeFries et al.)

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set consists of a southern African subset of the 1-km Global Tree Cover Data Set developed at the Laboratory for Global Remote Sensing Studies (LGRSS) at...

  1. Richness and epiphytic mosses cover variation on ironwood trees (Parrotia persica Pojark trunks

    Directory of Open Access Journals (Sweden)

    Seyedeh Rahimeh Yavarynik

    2016-06-01

    Full Text Available This research was conducted to determination and assess changes in richness and cover of epiphytic mosses on ironwood trees(Parrotia persica Pojark trunks along trunk elevation and slope aspect gradients, in lowland and protected forest of Natural Resource College of Tarbiat Modares University (Parts of western limit of Noor forest reserved. To do this, a number of 20 individual of ironwood trees with a diamerter higher than 40 cm were selected randomly in the study area. A rectangle with 40*30 cm in two geographical directions (Northern and Southern, in 4 height classes (from 0 to 160cm on the trunks was sampled and related characteristics were recorded. Results of floristic study showed that presence of 17 epiphytic mosses species and the endemic species Palamocladium euchloron among the species with highest presence and Brachytheciaceae family with 7 species were the most important taxa and family in the forest. Richness and cover percentage of epiphytic mosses had the highest averages in northern and lower parts of the trees trunk, this could be due to higher moisture in northern direction and lower parts of the trunk. Result of the study, well clarified the changes of distribution and abundance of the most important forest elements in relationship changes of geographical situation of Parrotia persica trunks.

  2. LBA Regional Tree Cover from AVHRR, 1-km, 1992-1993 (DeFries et al.)

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set is a subset of the 1-km global tree cover data set (DeFries et al. 1999) developed at the Laboratory for Global Remote Sensing Studies...

  3. Improving Land Use/Land Cover Classification by Integrating Pixel Unmixing and Decision Tree Methods

    Directory of Open Access Journals (Sweden)

    Chao Yang

    2017-11-01

    Full Text Available Decision tree classification is one of the most efficient methods for obtaining land use/land cover (LULC information from remotely sensed imageries. However, traditional decision tree classification methods cannot effectively eliminate the influence of mixed pixels. This study aimed to integrate pixel unmixing and decision tree to improve LULC classification by removing mixed pixel influence. The abundance and minimum noise fraction (MNF results that were obtained from mixed pixel decomposition were added to decision tree multi-features using a three-dimensional (3D Terrain model, which was created using an image fusion digital elevation model (DEM, to select training samples (ROIs, and improve ROI separability. A Landsat-8 OLI image of the Yunlong Reservoir Basin in Kunming was used to test this proposed method. Study results showed that the Kappa coefficient and the overall accuracy of integrated pixel unmixing and decision tree method increased by 0.093% and 10%, respectively, as compared with the original decision tree method. This proposed method could effectively eliminate the influence of mixed pixels and improve the accuracy in complex LULC classifications.

  4. LBA Regional Tree Cover from AVHRR, 1-km, 1992-1993 (DeFries et al.)

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set is a subset of the 1-km global tree cover data set (DeFries et al. 1999) developed at the Laboratory for Global Remote Sensing Studies (LGRSS) at the...

  5. Mobbing call experiment suggests the enhancement of forest bird movement by tree cover in urban landscapes across seasons

    Directory of Open Access Journals (Sweden)

    Atsushi Shimazaki

    2017-06-01

    Full Text Available Local scale movement behavior is an important basis to predict large-scale bird movements in heterogeneous landscapes. Here we conducted playback experiments using mobbing calls to estimate the probability that forest birds would cross a 50-m urban area during three seasons (breeding, dispersal, and wintering seasons with varying amounts of tree cover, building area, and electric wire density. We examined the responses of four forest resident species: Marsh Tit (Poecile palustris, Varied Tit (Sittiparus varius, Japanese Tit (P. minor, and Eurasian Nuthatch (Sitta europaea in central Hokkaido, northern Japan. We carried out and analyzed 250 playback experiments that attracted 618 individuals. Our results showed that tree cover increased the crossing probability of three species other than Varied Tit. Building area and electric wire density had no detectable effect on crossing probability for four species. Seasonal difference in the crossing probability was found only for Varied Tit, and the probability was the highest in the breeding season. These results suggest that the positive effect of tree cover on the crossing probability would be consistent across seasons. We therefore conclude that planting trees would be an effective way to promote forest bird movement within an urban landscape.

  6. Tree Plantation Will not Compensate Natural Woody Vegetation Cover Loss in the Atlantic Department of Southern Benin

    Directory of Open Access Journals (Sweden)

    Toyi, MS.

    2013-01-01

    Full Text Available This study deals with land use and land cover changes for a 33 years period. We assessed these changes for eight land cover classes in the south of Benin by using an integrated multi-temporal analysis using three Landsat images (1972 Landsat MSS, 1986 Landsat TM and 2005 Landsat ETM+. Three scenarios for the future were simulated using a first-order Markovian model based on annual probability matrices. The contribution of tree plantations to compensate forest loss was assessed. The results show a strong loss of forest and savanna, mainly due to increased agricultural land. Natural woody vegetation ("forest", "wooded savanna" and "tree and shrub savanna" will seriously decrease by 2025 due to the expansion of agricultural activities and the increase of settlements. Tree plantations are expected to double by 2025, but they will not compensate for the loss of natural woody vegetation cover. Consequently, we assist to a continuing woody vegetation area decrease. Policies regarding reforestation and forest conservation must be initiated to reverse the currently projected tendencies.

  7. Does Certification Change the Trajectory of Tree Cover in Working Forests in The Tropics? An Application of the Synthetic Control Method of Impact Evaluation

    Directory of Open Access Journals (Sweden)

    Pushpendra Rana

    2018-02-01

    Full Text Available Certification by the Forest Stewardship Council (FSC remains rare among forest management units (FMUs in natural tropical forests, presenting a challenge for impact evaluation. We demonstrate application of the synthetic control method (SCM to evaluate the impact of FSC certification on a single FMU in each of three tropical forest landscapes. Specifically, we estimate causal effects on tree cover change from the year of certification to 2012 using SCM and open-access, pan-tropical datasets. We demonstrate that it is possible to construct synthetic controls, or weighted combinations of non-certified FMUs, that followed the same path of tree cover change as the certified FMUs before certification. By using these synthetic controls to measure counterfactual tree cover change after certification, we find that certification reduced tree cover loss in the most recent year (2012 in all three landscapes. However, placebo tests show that in one case, this effect was not significant, and in another case, it followed several years in which certification had the opposite effect (increasing tree cover loss. We conclude that SCM has promise for identifying temporally varying impacts of small-N interventions on land use and land cover change.

  8. An Evaluation of Different Training Sample Allocation Schemes for Discrete and Continuous Land Cover Classification Using Decision Tree-Based Algorithms

    Directory of Open Access Journals (Sweden)

    René Roland Colditz

    2015-07-01

    Full Text Available Land cover mapping for large regions often employs satellite images of medium to coarse spatial resolution, which complicates mapping of discrete classes. Class memberships, which estimate the proportion of each class for every pixel, have been suggested as an alternative. This paper compares different strategies of training data allocation for discrete and continuous land cover mapping using classification and regression tree algorithms. In addition to measures of discrete and continuous map accuracy the correct estimation of the area is another important criteria. A subset of the 30 m national land cover dataset of 2006 (NLCD2006 of the United States was used as reference set to classify NADIR BRDF-adjusted surface reflectance time series of MODIS at 900 m spatial resolution. Results show that sampling of heterogeneous pixels and sample allocation according to the expected area of each class is best for classification trees. Regression trees for continuous land cover mapping should be trained with random allocation, and predictions should be normalized with a linear scaling function to correctly estimate the total area. From the tested algorithms random forest classification yields lower errors than boosted trees of C5.0, and Cubist shows higher accuracies than random forest regression.

  9. Using laser altimetry-based segmentation to refine automated tree identification in managed forests of the Black Hills, South Dakota

    Science.gov (United States)

    Eric Rowell; Carl Selelstad; Lee Vierling; Lloyd Queen; Wayne Sheppard

    2006-01-01

    The success of a local maximum (LM) tree detection algorithm for detecting individual trees from lidar data depends on stand conditions that are often highly variable. A laser height variance and percent canopy cover (PCC) classification is used to segment the landscape by stand condition prior to stem detection. We test the performance of the LM algorithm using canopy...

  10. The Association Between Urban Tree Cover and Gun Assault: A Case-Control and Case-Crossover Study.

    Science.gov (United States)

    Kondo, Michelle C; South, Eugenia C; Branas, Charles C; Richmond, Therese S; Wiebe, Douglas J

    2017-08-01

    Green space and vegetation may play a protective role against urban violence. We investigated whether being near urban tree cover during outdoor activities was related to being assaulted with a gun. We conducted geographic information systems-assisted interviews with boys and men aged 10-24 years in Philadelphia, Pennsylvania, including 135 patients who had been shot with a firearm and 274 community controls, during 2008-2011. Each subject reported a step-by-step mapped account of where and with whom they traveled over a full day from waking until being assaulted or going to bed. Geocoded path points were overlaid on mapped layers representing tree locations and place-specific characteristics. Conditional logistic regressions were used to compare case subjects versus controls (case-control) and case subjects at the time of injury versus times earlier that day (case-crossover). When comparing cases at the time of assault to controls matched at the same time of day, being under tree cover was inversely associated with gunshot assault (odds ratio (OR) = 0.70, 95% confidence interval (CI): 0.55, 0.88), especially in low-income areas (OR = 0.69, 95% CI: 0.54, 0.87). Case-crossover models confirmed this inverse association overall (OR = 0.55, 95% CI: 0.34, 0.89) and in low-income areas (OR = 0.54, 95% CI: 0.33, 0.88). Urban greening and tree cover may hold promise as proactive strategies to decrease urban violence. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  11. Richer histories for more relevant policies: 42 years of tree cover loss and gain in Southeast Sulawesi, Indonesia.

    Science.gov (United States)

    Kelley, Lisa C; Evans, Samuel G; Potts, Matthew D

    2017-02-01

    Understandings of contemporary forest cover loss are critical for policy but have come at the expense of long-term, multidirectional analyses of land cover change. This is a critical gap given (i) profound reconfigurations in land use and land control over the past several decades and (ii) evidence of widespread 'woodland resurgence' throughout the tropics. In this study, we argue that recent advancements within the field of land change science provide new opportunities to address this gap. In turn, we suggest that multidecadal and multidirectional analyses of land cover change can facilitate richer social analyses of land cover change and more relevant conservation policies and practice. Our argument is grounded in a case study from Southeast Sulawesi, Indonesia. Using a novel analytical platform, Google Earth Engine, and open access to high-quality Landsat data, we map land cover change in Southeast Sulawesi, Indonesia, from 1972 to 2014. We find that tree cover loss constitutes the single largest net change over the period 1972-2014 but that gross rates of tree cover gain were three times higher than gross loss rates from 1972 to 1995 and equivalent to loss rates from 1995 to 2014. We suggest the smallholder tree crop economy likely produced both forest loss and Imperata grassland restoration in this region. This case points to the need to expand rather than collapse the baselines used to study carbon and biodiversity change in tropical regions. It also demonstrates the possible utility of applying such methods to other regions. © 2016 John Wiley & Sons Ltd.

  12. Ground cover and tree growth on calcareous minesoils: Greater influence of soil surface than nitrogen rate or seed mix

    International Nuclear Information System (INIS)

    Kost, D.A.; Vimmerstedt, J.P.

    1994-01-01

    Growth of ground cover and trees was evaluated for five growing seasons on calcareous coal minesoil surfaces (standard graded topsoil, graded and ripped topsoil, graded gray cast overburden) in southeastern Ohio. Soil surface plots were seeded in September 1987 with either a standard herbaceous seed mix [orchardgrass (Dactylis glomerata L.), timothy (Phleum pratense L.), perennial ryegrass (Lolium perenne L.), Kentucky bluegrass (Poa pratensis L.), Ranger alfalfa (Medicago sativa L.), Mammoth red clover (Trifolium pratense L.), Empire birdsfoot trefoil (Lotus corniculatus L.), and wheat (Triticum aestivum L.)], or a modified mix using no alfalfa and half the rate of orchardgrass. Nitrogen (45, 90, or 135 kg ha/N) was applied as ammonium nitrate in September 1987 and April 1989. White ash (Fraxinus americana L.), silver maple (Acer saccharinum L.), northern red oak (Quercus rubra L.), and eastern white pine (Pinus strobus L.) were planted in spring 1989 into 0.8 m-wide strips sprayed with glyphosate herbicide at 2.24 kg/ha in October 1988. Total cover and total biomass were highest in July 1989, following the last application of nitrogen fertilizer in April 1989. Total cover ranged from 44% to 56%, and total biomass ranged from 102 to 162 g/0.5 m 2 from 1990 to 1993. Total cover and total biomass were lower at the lowest nitrogen rate in 1989 only. Type of herbaceous seed mix did not affect growth of ground cover or trees. Overall tree survival was 82.0% the first year but declined to 40.6% after 5 yr. Survival varied significantly among all tree species (3.5% for pine, 22.2% for oak, 38.5% for maple, 98.1% for ash)

  13. Aboveground Net Primary Production of tree cover at the post-disturbance area in the Tatra National Park, Slovakia

    Directory of Open Access Journals (Sweden)

    Konôpka Bohdan

    2015-09-01

    Full Text Available Large-scale disturbances under the conditions of Slovakia, caused especially by storm and bark beetle, bring dramatic decline in carbon budget of the country, besides other negative consequences. The largest disturbance in modern history of the Slovak forestry was the storm damage that occurred in November 2004. The Tatra National Park (TNP was one of the most affected regions. Thus, in this territory, two transects (T1 – the Danielov dom site and T2 – near the Horný Smokovec village were established to survey basic dendrometric properties of trees in young stands established after the disaster. The standing stock of aboveground biomass in tree cover for the spring and autumn 2014 was calculated using the recorded variables, i.e. tree height and diameter measured at the stem base, together with the region-specific allometric relations. Then, the Aboveground Net Primary Production (ANPP in tree cover was estimated with respect to its components (stem, branches and foliage. ANPP was 315 g m−2 per year (Transect T1, and 391 g m−2 per year (Transect T2. The differences in the structure of ANPP, i.e. contribution of tree components, were found between transects T1 and T2. They were caused by the contrasting tree species composition, specifically the ratios between Norway spruce and broadleaved species. Broadleaves allocated more biomass production to foliage than spruce. This phenomenon together with higher turnover (once a year of foliage caused that broadleaves manifest higher share of fast-cycling carbon in comparison to the amount of carbon sequestrated in woody parts (stem and branches. High variability of ANPP was found within the transects, i.e. among the plots (microsites. As for the representative estimation of the standing stock of aboveground part of tree cover as well as ANPP at the post-disturbance area in the TNP territory, the survey should be performed on a net of research plots. Only this approach enables reliable estimates

  14. Increasing tree cover in degrading landscapes

    DEFF Research Database (Denmark)

    Rahman, Syed Ajijur; Rahman, Md Faizar; Sunderland, Terry

    2014-01-01

    -functionality’. Two agroforestry models suitable for adoption by farmers have been identified. Multi-strata agroforestry, based on a fruit and timber tree canopy with vegetables and tuber species in the understorey, can be practiced in the shifting cultivation fields near settlements. Fruit and timber tree......Research was conducted in Alutilla Valley in eastern Bangladesh to identify the nature of existing agroforestry systems and to identify potential agroforestry models that could ameliorate currently degrading forest resources Data were collected through farmer participatory research and a structured......-based conservation agroforestry is well suited to manage large-scale biologically depleted landscapes. Both systems yield early financial returns, facilitating the change from shifting cultivation to multi-strata agroforestry or fruit and tree-based conservation agroforestry....

  15. Matter power spectrum and the challenge of percent accuracy

    International Nuclear Information System (INIS)

    Schneider, Aurel; Teyssier, Romain; Potter, Doug; Stadel, Joachim; Reed, Darren S.; Onions, Julian; Pearce, Frazer R.; Smith, Robert E.; Springel, Volker; Scoccimarro, Roman

    2016-01-01

    Future galaxy surveys require one percent precision in the theoretical knowledge of the power spectrum over a large range including very nonlinear scales. While this level of accuracy is easily obtained in the linear regime with perturbation theory, it represents a serious challenge for small scales where numerical simulations are required. In this paper we quantify the precision of present-day N -body methods, identifying main potential error sources from the set-up of initial conditions to the measurement of the final power spectrum. We directly compare three widely used N -body codes, Ramses, Pkdgrav3, and Gadget3 which represent three main discretisation techniques: the particle-mesh method, the tree method, and a hybrid combination of the two. For standard run parameters, the codes agree to within one percent at k ≤1 h Mpc −1 and to within three percent at k ≤10 h Mpc −1 . We also consider the bispectrum and show that the reduced bispectra agree at the sub-percent level for k ≤ 2 h Mpc −1 . In a second step, we quantify potential errors due to initial conditions, box size, and resolution using an extended suite of simulations performed with our fastest code Pkdgrav3. We demonstrate that the simulation box size should not be smaller than L =0.5 h −1 Gpc to avoid systematic finite-volume effects (while much larger boxes are required to beat down the statistical sample variance). Furthermore, a maximum particle mass of M p =10 9 h −1 M ⊙ is required to conservatively obtain one percent precision of the matter power spectrum. As a consequence, numerical simulations covering large survey volumes of upcoming missions such as DES, LSST, and Euclid will need more than a trillion particles to reproduce clustering properties at the targeted accuracy.

  16. CRED Cumulative Map of Percent Scleractinian Coral Cover at Sarigan

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  17. CRED Cumulative Map of Percent Scleractinian Coral Cover at Saipan

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  18. CRED Cumulative Map of Percent Scleractinian Coral Cover at Tutuila

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  19. CRED Cumulative Map of Percent Scleractinian Coral Cover at Anatahan

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  20. CRED Cumulative Map of Percent Scleractinian Coral Cover at Alamagan

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  1. CRED Cumulative Map of Percent Scleractinian Coral Cover at Agrihan

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  2. CRED Cumulative Map of Percent Scleractinian Coral Cover at Pagan

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  3. CRED Cumulative Map of Percent Scleractinian Coral Cover at Asuncion

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  4. CRED Cumulative Map of Percent Scleractinian Coral Cover at Aguijan

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  5. Comparison of hyporheic flow and water quality in open and tree-covered banks downstream of Xin'an River dam, China

    Science.gov (United States)

    Liu, D.

    2017-12-01

    Plants, especially trees, in the riparian zone may have a significant impact on the flow rate, temperature and chemical properties of groundwater. A field study was conducted in the downstream bank of the Xin'an River dam, Zhejiang, China. In the field, two areas of about 20 meters apart were chosen, of which one was a open place and the other was covered with many orange trees. Comparison of hyporheic flow and water quality in the open and tree-covered banks were made by monitoring the water level, water temperature, water chemistry (March, 2015) along the cross sections perpendicular to the river. The analyses indicated that water level around the trees was relatively low in the day and high in the evening, thus changed the direction and magnitude of the natural groundwater flow velocity, totally strengthened the hyporheic exchange between the groundwater and river. The trees also changed the temperature distribution of the natural river bank, and induced the wider infiltration range of the low-temperature water. The temperature around the trees was relatively low in the day, yet it was high in the evening. Dissolved oxygen (DO) and electricity conductivity (EC) around the trees were significantly increased, yet the pH was almost unaffected.

  6. Response of land surface phenology to variation in tree cover during green-up and senescence periods in the semi-arid savanna of Southern Africa

    CSIR Research Space (South Africa)

    Cho, Moses A

    2017-07-01

    Full Text Available ) seasonal time series (2001 to 2015) maps for a study region in South Africa. Tree cover (%) data for 100 randomly selected polygons grouped into three tree cover classes: low (< 20%, n = 44), medium (20-40%, n = 22) and high (> 40%, n = 34) were used...

  7. GENERATION OF 2D LAND COVER MAPS FOR URBAN AREAS USING DECISION TREE CLASSIFICATION

    DEFF Research Database (Denmark)

    Höhle, Joachim

    2014-01-01

    A 2D land cover map can automatically and efficiently be generated from high-resolution multispectral aerial images. First, a digital surface model is produced and each cell of the elevation model is then supplemented with attributes. A decision tree classification is applied to extract map objects...... of stereo-observations of false-colour stereopairs. The stratified statistical assessment of the produced land cover map with six classes and based on 91 points per class reveals a high thematic accuracy for classes ‘building’ (99%, 95% CI: 95%-100%) and ‘road and parking lot’ (90%, 95% CI: 83%-95%). Some...

  8. Measurement of NO2 pollutant sorption of various trees, shrubs and ground cover plants using gas NO2 labelled 15N

    International Nuclear Information System (INIS)

    Nasrullah, Nizar; Wungkar, Marietje; Gunawan, Andi; Gandanegara, Soertini; Suharsono, Heny

    2000-01-01

    The objective of this study is to measure the NO 2 pollutant sorption of various trees, shrubs and ground cover plants. 32 species of trees, 64 speceis of shrubs and 13 species of ground cover plants were exposed to 3 ppm (v / v) N- 15 O 2 in a gas chamber for 60 minutes. Experiment consisted of 2 replicates. The environment conditions in the chamber were set at 30 o C, 1000 lux, and initial relative humidity 60 %. After gas treatment, plants parts were separated into leaves, stems and roots, than dried in 70 o C for 48 hours and then weighed. After weighing, those plants parts were ground to a pine powder. After kjendhal digestion, N total content of plants were analyzed by distillation method. 15 N content of plant samples were analyzed by emission spectrometer ( Yasco, N-151). The amount of N-15 absorbed by plant was the total content of 15 N in the whole plants ( leaves, stem and root ) per gram dry weight of leaves. The amount of 15 N absorbed by plants varied among investigated plants. 15 N sorption of trees are in the range 0.28 - 68.31μg/g. The sorption of shrubs and ground cover plants varied in 1.97 - 100.02 μg/g and 2.38 - 24.06μg/g, respectively. According to the amount of 15 N sorption , the plants were divided into 3 groups of sorption level, high ( > 30.0μg/g), moderate ( 15 - 30 μg/g ), and low sorption level ( 15 μg/g). Results showed that among of 32 investigated trees, 64 shrubs and 13 ground cover plant, 4 species of trees and 13 species of shrubs performed a high sorption level and no one of ground cover plants performed a high sorption level. The species of trees and 15 species of shrubs that mention above are recommended to use as an element of landscape which to be functioned to reduce NO 2 atmospheric pollutant

  9. Heterogeneous Compression of Large Collections of Evolutionary Trees.

    Science.gov (United States)

    Matthews, Suzanne J

    2015-01-01

    Compressing heterogeneous collections of trees is an open problem in computational phylogenetics. In a heterogeneous tree collection, each tree can contain a unique set of taxa. An ideal compression method would allow for the efficient archival of large tree collections and enable scientists to identify common evolutionary relationships over disparate analyses. In this paper, we extend TreeZip to compress heterogeneous collections of trees. TreeZip is the most efficient algorithm for compressing homogeneous tree collections. To the best of our knowledge, no other domain-based compression algorithm exists for large heterogeneous tree collections or enable their rapid analysis. Our experimental results indicate that TreeZip averages 89.03 percent (72.69 percent) space savings on unweighted (weighted) collections of trees when the level of heterogeneity in a collection is moderate. The organization of the TRZ file allows for efficient computations over heterogeneous data. For example, consensus trees can be computed in mere seconds. Lastly, combining the TreeZip compressed (TRZ) file with general-purpose compression yields average space savings of 97.34 percent (81.43 percent) on unweighted (weighted) collections of trees. Our results lead us to believe that TreeZip will prove invaluable in the efficient archival of tree collections, and enables scientists to develop novel methods for relating heterogeneous collections of trees.

  10. Influence of tree cover on herbaceous layer development and carbon and water fluxes in a Portuguese cork-oak woodland

    Science.gov (United States)

    Dubbert, Maren; Mosena, Alexander; Piayda, Arndt; Cuntz, Matthias; Correia, Alexandra Cristina; Pereira, Joao Santos; Werner, Christiane

    2014-08-01

    Facilitation and competition between different vegetation layers may have a large impact on small-scale vegetation development. We propose that this should not only influence overall herbaceous layer yield but also species distribution and understory longevity, and hence the ecosystems carbon uptake capacity especially during spring. We analyzed the effects of trees on microclimate and soil properties (water and nitrate content) as well as the development of an herbaceous community layer regarding species composition, aboveground biomass and net water and carbon fluxes in a cork-oak woodland in Portugal, between April and November 2011. The presence of trees caused a significant reduction in photosynthetic active radiation of 35 mol m-2 d-1 and in soil temperature of 5 °C from April to October. At the same time differences in species composition between experimental plots located in open areas and directly below trees could be observed: species composition and abundance of functional groups became increasingly different between locations from mid April onwards. During late spring drought adapted native forbs had significantly higher cover and biomass in the open area while cover and biomass of grasses and nitrogen fixing forbs was highest under the trees. Further, evapotranspiration and net carbon exchange decreased significantly stronger under the tree crowns compared to the open during late spring and the die back of herbaceous plants occurred earlier and faster under trees. This was most likely caused by interspecific competition for water between trees and herbaceous plants, despite the more favorable microclimate conditions under the trees during the onset of summer drought.

  11. Land Cover Mapping using GEOBIA to Estimate Loss of Salacca zalacca Trees in Landslide Area of Clapar, Madukara District of Banjarnegara

    Science.gov (United States)

    Permata, Anggi; Juniansah, Anwar; Nurcahyati, Eka; Dimas Afrizal, Mousafi; Adnan Shafry Untoro, Muhammad; Arifatha, Na'ima; Ramadhani Yudha Adiwijaya, Raden; Farda, Nur Mohammad

    2016-11-01

    Landslide is an unpredictable natural disaster which commonly happens in highslope area. Aerial photography in small format is one of acquisition method that can reach and obtain high resolution spatial data faster than other methods, and provide data such as orthomosaic and Digital Surface Model (DSM). The study area contained landslide area in Clapar, Madukara District of Banjarnegara. Aerial photographs of landslide area provided advantage in objects visibility. Object's characters such as shape, size, and texture were clearly seen, therefore GEOBIA (Geography Object Based Image Analysis) was compatible as method for classifying land cover in study area. Dissimilar with PPA (PerPixel Analyst) method that used spectral information as base object detection, GEOBIA could use spatial elements as classification basis to establish a land cover map with better accuracy. GEOBIA method used classification hierarchy to divide post disaster land cover into three main objects: vegetation, landslide/soil, and building. Those three were required to obtain more detailed information that can be used in estimating loss caused by landslide and establishing land cover map in landslide area. Estimating loss in landslide area related to damage in Salak (Salacca zalacca) plantations. This estimation towards quantity of Salak tree that were drifted away by landslide was calculated in assumption that every tree damaged by landslide had same age and production class with other tree that weren't damaged. Loss calculation was done by approximating quantity of damaged trees in landslide area with data of trees around area that were acquired from GEOBIA classification method.

  12. Matter power spectrum and the challenge of percent accuracy

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Aurel; Teyssier, Romain; Potter, Doug; Stadel, Joachim; Reed, Darren S. [Institute for Computational Science, University of Zurich, Winterthurerstrasse 190, 8057 Zurich (Switzerland); Onions, Julian; Pearce, Frazer R. [School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD (United Kingdom); Smith, Robert E. [Department of Physics and Astronomy, University of Sussex, Brighton, BN1 9QH (United Kingdom); Springel, Volker [Heidelberger Institut für Theoretische Studien, 69118 Heidelberg (Germany); Scoccimarro, Roman, E-mail: aurel@physik.uzh.ch, E-mail: teyssier@physik.uzh.ch, E-mail: dpotter@physik.uzh.ch, E-mail: stadel@physik.uzh.ch, E-mail: julian.onions@nottingham.ac.uk, E-mail: reed@physik.uzh.ch, E-mail: r.e.smith@sussex.ac.uk, E-mail: volker.springel@h-its.org, E-mail: Frazer.Pearce@nottingham.ac.uk, E-mail: rs123@nyu.edu [Center for Cosmology and Particle Physics, Department of Physics, New York University, NY 10003, New York (United States)

    2016-04-01

    Future galaxy surveys require one percent precision in the theoretical knowledge of the power spectrum over a large range including very nonlinear scales. While this level of accuracy is easily obtained in the linear regime with perturbation theory, it represents a serious challenge for small scales where numerical simulations are required. In this paper we quantify the precision of present-day N -body methods, identifying main potential error sources from the set-up of initial conditions to the measurement of the final power spectrum. We directly compare three widely used N -body codes, Ramses, Pkdgrav3, and Gadget3 which represent three main discretisation techniques: the particle-mesh method, the tree method, and a hybrid combination of the two. For standard run parameters, the codes agree to within one percent at k ≤1 h Mpc{sup −1} and to within three percent at k ≤10 h Mpc{sup −1}. We also consider the bispectrum and show that the reduced bispectra agree at the sub-percent level for k ≤ 2 h Mpc{sup −1}. In a second step, we quantify potential errors due to initial conditions, box size, and resolution using an extended suite of simulations performed with our fastest code Pkdgrav3. We demonstrate that the simulation box size should not be smaller than L =0.5 h {sup −1}Gpc to avoid systematic finite-volume effects (while much larger boxes are required to beat down the statistical sample variance). Furthermore, a maximum particle mass of M {sub p}=10{sup 9} h {sup −1}M{sub ⊙} is required to conservatively obtain one percent precision of the matter power spectrum. As a consequence, numerical simulations covering large survey volumes of upcoming missions such as DES, LSST, and Euclid will need more than a trillion particles to reproduce clustering properties at the targeted accuracy.

  13. CRED Cumulative Map of Percent Scleractinian Coral Cover at Kauai, 2005

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  14. CRED Cumulative Map of Percent Scleractinian Coral Cover at Niihau, 2005

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  15. CRED Cumulative Map of Percent Scleractinian Coral Cover at Stingray Shoals

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  16. CRED Cumulative Map of Percent Scleractinian Coral Cover at Molokai, 2005

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  17. CRED Cumulative Map of Percent Scleractinian Coral Cover at Ofu & Olosega

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  18. CRED Cumulative Map of Percent Scleractinian Coral Cover at Ta'u

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  19. CRED Cumulative Map of Percent Scleractinian Coral Cover at Guam, 2003

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  20. Digital Cover Photography for Estimating Leaf Area Index (LAI in Apple Trees Using a Variable Light Extinction Coefficient

    Directory of Open Access Journals (Sweden)

    Carlos Poblete-Echeverría

    2015-01-01

    Full Text Available Leaf area index (LAI is one of the key biophysical variables required for crop modeling. Direct LAI measurements are time consuming and difficult to obtain for experimental and commercial fruit orchards. Devices used to estimate LAI have shown considerable errors when compared to ground-truth or destructive measurements, requiring tedious site-specific calibrations. The objective of this study was to test the performance of a modified digital cover photography method to estimate LAI in apple trees using conventional digital photography and instantaneous measurements of incident radiation (Io and transmitted radiation (I through the canopy. Leaf area of 40 single apple trees were measured destructively to obtain real leaf area index (LAID, which was compared with LAI estimated by the proposed digital photography method (LAIM. Results showed that the LAIM was able to estimate LAID with an error of 25% using a constant light extinction coefficient (k = 0.68. However, when k was estimated using an exponential function based on the fraction of foliage cover (ff derived from images, the error was reduced to 18%. Furthermore, when measurements of light intercepted by the canopy (Ic were used as a proxy value for k, the method presented an error of only 9%. These results have shown that by using a proxy k value, estimated by Ic, helped to increase accuracy of LAI estimates using digital cover images for apple trees with different canopy sizes and under field conditions.

  1. Digital cover photography for estimating leaf area index (LAI) in apple trees using a variable light extinction coefficient.

    Science.gov (United States)

    Poblete-Echeverría, Carlos; Fuentes, Sigfredo; Ortega-Farias, Samuel; Gonzalez-Talice, Jaime; Yuri, Jose Antonio

    2015-01-28

    Leaf area index (LAI) is one of the key biophysical variables required for crop modeling. Direct LAI measurements are time consuming and difficult to obtain for experimental and commercial fruit orchards. Devices used to estimate LAI have shown considerable errors when compared to ground-truth or destructive measurements, requiring tedious site-specific calibrations. The objective of this study was to test the performance of a modified digital cover photography method to estimate LAI in apple trees using conventional digital photography and instantaneous measurements of incident radiation (Io) and transmitted radiation (I) through the canopy. Leaf area of 40 single apple trees were measured destructively to obtain real leaf area index (LAI(D)), which was compared with LAI estimated by the proposed digital photography method (LAI(M)). Results showed that the LAI(M) was able to estimate LAI(D) with an error of 25% using a constant light extinction coefficient (k = 0.68). However, when k was estimated using an exponential function based on the fraction of foliage cover (f(f)) derived from images, the error was reduced to 18%. Furthermore, when measurements of light intercepted by the canopy (Ic) were used as a proxy value for k, the method presented an error of only 9%. These results have shown that by using a proxy k value, estimated by Ic, helped to increase accuracy of LAI estimates using digital cover images for apple trees with different canopy sizes and under field conditions.

  2. Digital Cover Photography for Estimating Leaf Area Index (LAI) in Apple Trees Using a Variable Light Extinction Coefficient

    Science.gov (United States)

    Poblete-Echeverría, Carlos; Fuentes, Sigfredo; Ortega-Farias, Samuel; Gonzalez-Talice, Jaime; Yuri, Jose Antonio

    2015-01-01

    Leaf area index (LAI) is one of the key biophysical variables required for crop modeling. Direct LAI measurements are time consuming and difficult to obtain for experimental and commercial fruit orchards. Devices used to estimate LAI have shown considerable errors when compared to ground-truth or destructive measurements, requiring tedious site-specific calibrations. The objective of this study was to test the performance of a modified digital cover photography method to estimate LAI in apple trees using conventional digital photography and instantaneous measurements of incident radiation (Io) and transmitted radiation (I) through the canopy. Leaf area of 40 single apple trees were measured destructively to obtain real leaf area index (LAID), which was compared with LAI estimated by the proposed digital photography method (LAIM). Results showed that the LAIM was able to estimate LAID with an error of 25% using a constant light extinction coefficient (k = 0.68). However, when k was estimated using an exponential function based on the fraction of foliage cover (ff) derived from images, the error was reduced to 18%. Furthermore, when measurements of light intercepted by the canopy (Ic) were used as a proxy value for k, the method presented an error of only 9%. These results have shown that by using a proxy k value, estimated by Ic, helped to increase accuracy of LAI estimates using digital cover images for apple trees with different canopy sizes and under field conditions. PMID:25635411

  3. Gainesville's urban forest canopy cover

    Science.gov (United States)

    Francisco Escobedo; Jennifer A. Seitz; Wayne Zipperer

    2009-01-01

    Ecosystem benefits from trees are linked directly to the amount of healthy urban forest canopy cover. Urban forest cover is dynamic and changes over time due to factors such as urban development, windstorms, tree removals, and growth. The amount of a city's canopy cover depends on its land use, climate, and people's preferences. This fact sheet examines how...

  4. Land cover and forest formation distributions for St. Kitts, Nevis, St. Eustatius, Grenada and Barbados from decision tree classification of cloud-cleared satellite imagery

    Science.gov (United States)

    Helmer, E.H.; Kennaway, T.A.; Pedreros, D.H.; Clark, M.L.; Marcano-Vega, H.; Tieszen, L.L.; Ruzycki, T.R.; Schill, S.R.; Carrington, C.M.S.

    2008-01-01

    Satellite image-based mapping of tropical forests is vital to conservation planning. Standard methods for automated image classification, however, limit classification detail in complex tropical landscapes. In this study, we test an approach to Landsat image interpretation on four islands of the Lesser Antilles, including Grenada and St. Kitts, Nevis and St. Eustatius, testing a more detailed classification than earlier work in the latter three islands. Secondly, we estimate the extents of land cover and protected forest by formation for five islands and ask how land cover has changed over the second half of the 20th century. The image interpretation approach combines image mosaics and ancillary geographic data, classifying the resulting set of raster data with decision tree software. Cloud-free image mosaics for one or two seasons were created by applying regression tree normalization to scene dates that could fill cloudy areas in a base scene. Such mosaics are also known as cloud-filled, cloud-minimized or cloud-cleared imagery, mosaics, or composites. The approach accurately distinguished several classes that more standard methods would confuse; the seamless mosaics aided reference data collection; and the multiseason imagery allowed us to separate drought deciduous forests and woodlands from semi-deciduous ones. Cultivated land areas declined 60 to 100 percent from about 1945 to 2000 on several islands. Meanwhile, forest cover has increased 50 to 950%. This trend will likely continue where sugar cane cultivation has dominated. Like the island of Puerto Rico, most higher-elevation forest formations are protected in formal or informal reserves. Also similarly, lowland forests, which are drier forest types on these islands, are not well represented in reserves. Former cultivated lands in lowland areas could provide lands for new reserves of drier forest types. The land-use history of these islands may provide insight for planners in countries currently considering

  5. The association between urban tree cover and gun assault: A case-control and case-crossover study

    Science.gov (United States)

    Michelle C. Kondo; Eugenia C. South; Charles C. Branas; Therese S. Richmond; Douglas J. Wiebe

    2017-01-01

    Green space and vegetation may play a protective role against urban violence. We investigated whether being near urban tree cover during outdoor activities was related to being assaulted with a gun. We conducted geographic information systems–assisted interviews with boys andmen aged 10–24 years in Philadelphia, Pennsylvania, including 135 patients who had been shot...

  6. DeepSAT: A Deep Learning Approach to Tree-cover Delineation in 1-m NAIP Imagery for the Continental United States

    Science.gov (United States)

    Ganguly, S.; Basu, S.; Nemani, R. R.; Mukhopadhyay, S.; Michaelis, A.; Votava, P.

    2016-12-01

    High resolution tree cover classification maps are needed to increase the accuracy of current land ecosystem and climate model outputs. Limited studies are in place that demonstrates the state-of-the-art in deriving very high resolution (VHR) tree cover products. In addition, most methods heavily rely on commercial softwares that are difficult to scale given the region of study (e.g. continents to globe). Complexities in present approaches relate to (a) scalability of the algorithm, (b) large image data processing (compute and memory intensive), (c) computational cost, (d) massively parallel architecture, and (e) machine learning automation. In addition, VHR satellite datasets are of the order of terabytes and features extracted from these datasets are of the order of petabytes. In our present study, we have acquired the National Agriculture Imagery Program (NAIP) dataset for the Continental United States at a spatial resolution of 1-m. This data comes as image tiles (a total of quarter million image scenes with 60 million pixels) and has a total size of 65 terabytes for a single acquisition. Features extracted from the entire dataset would amount to 8-10 petabytes. In our proposed approach, we have implemented a novel semi-automated machine learning algorithm rooted on the principles of "deep learning" to delineate the percentage of tree cover. Using the NASA Earth Exchange (NEX) initiative, we have developed an end-to-end architecture by integrating a segmentation module based on Statistical Region Merging, a classification algorithm using Deep Belief Network and a structured prediction algorithm using Conditional Random Fields to integrate the results from the segmentation and classification modules to create per-pixel class labels. The training process is scaled up using the power of GPUs and the prediction is scaled to quarter million NAIP tiles spanning the whole of Continental United States using the NEX HPC supercomputing cluster. An initial pilot over the

  7. Tree Productivity Enhanced with Conversion from Forest to Urban Land Covers.

    Science.gov (United States)

    Briber, Brittain M; Hutyra, Lucy R; Reinmann, Andrew B; Raciti, Steve M; Dearborn, Victoria K; Holden, Christopher E; Dunn, Allison L

    2015-01-01

    Urban areas are expanding, changing the structure and productivity of landscapes. While some urban areas have been shown to hold substantial biomass, the productivity of these systems is largely unknown. We assessed how conversion from forest to urban land uses affected both biomass structure and productivity across eastern Massachusetts. We found that urban land uses held less than half the biomass of adjacent forest expanses with a plot level mean biomass density of 33.5 ± 8.0 Mg C ha(-1). As the intensity of urban development increased, the canopy cover, stem density, and biomass decreased. Analysis of Quercus rubra tree cores showed that tree-level basal area increment nearly doubled following development, increasing from 17.1 ± 3.0 to 35.8 ± 4.7 cm(2) yr(-1). Scaling the observed stem densities and growth rates within developed areas suggests an aboveground biomass growth rate of 1.8 ± 0.4 Mg C ha(-1) yr(-1), a growth rate comparable to nearby, intact forests. The contrasting high growth rates and lower biomass pools within urban areas suggest a highly dynamic ecosystem with rapid turnover. As global urban extent continues to grow, cities consider climate mitigation options, and as the verification of net greenhouse gas emissions emerges as critical for policy, quantifying the role of urban vegetation in regional-to-global carbon budgets will become ever more important.

  8. CRED Cumulative Map of Percent Scleractinian Coral Cover at Raita Bank, 2001

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  9. CRED Cumulative Map of Percent Scleractinian Coral Cover at Eleven-Mile Bank

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  10. CRED Cumulative Map of Percent Scleractinian Coral Cover at Gardner Pinnacles, 2003

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  11. CRED Cumulative Map of Percent Scleractinian Coral Cover at French Frigate Shoals

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  12. Tree Productivity Enhanced with Conversion from Forest to Urban Land Covers.

    Directory of Open Access Journals (Sweden)

    Brittain M Briber

    Full Text Available Urban areas are expanding, changing the structure and productivity of landscapes. While some urban areas have been shown to hold substantial biomass, the productivity of these systems is largely unknown. We assessed how conversion from forest to urban land uses affected both biomass structure and productivity across eastern Massachusetts. We found that urban land uses held less than half the biomass of adjacent forest expanses with a plot level mean biomass density of 33.5 ± 8.0 Mg C ha(-1. As the intensity of urban development increased, the canopy cover, stem density, and biomass decreased. Analysis of Quercus rubra tree cores showed that tree-level basal area increment nearly doubled following development, increasing from 17.1 ± 3.0 to 35.8 ± 4.7 cm(2 yr(-1. Scaling the observed stem densities and growth rates within developed areas suggests an aboveground biomass growth rate of 1.8 ± 0.4 Mg C ha(-1 yr(-1, a growth rate comparable to nearby, intact forests. The contrasting high growth rates and lower biomass pools within urban areas suggest a highly dynamic ecosystem with rapid turnover. As global urban extent continues to grow, cities consider climate mitigation options, and as the verification of net greenhouse gas emissions emerges as critical for policy, quantifying the role of urban vegetation in regional-to-global carbon budgets will become ever more important.

  13. Estimating pinyon and juniper cover across Utah using NAIP imagery

    Directory of Open Access Journals (Sweden)

    Darrell B. Roundy

    2016-11-01

    Full Text Available Expansion of Pinus L. (pinyon and Juniperus L. (juniper (P-J trees into sagebrush (Artemisia L. steppe communities can lead to negative effects on hydrology, loss of wildlife habitat, and a decrease in desirable understory vegetation. Tree reduction treatments are often implemented to mitigate these negative effects. In order to prioritize and effectively plan these treatments, rapid, accurate, and inexpensive methods are needed to estimate tree canopy cover at the landscape scale. We used object based image analysis (OBIA software (Feature AnalystTM for ArcMap 10.1®, ENVI Feature Extraction®, and Trimble eCognition Developer 8.2® to extract tree canopy cover using NAIP (National Agricultural Imagery Program imagery. We then compared our extractions with ground measured tree canopy cover (crown diameter and line point intercept on 309 plots across 44 sites in Utah. Extraction methods did not consistently over- or under-estimate ground measured P-J canopy cover except where tree cover was >45%. Estimates of tree canopy cover using OBIA techniques were strongly correlated with estimates using the crown diameter method (r = 0.93 for ENVI, 0.91 for Feature AnalystTM, and 0.92 for eCognition. Tree cover estimates using OBIA techniques had lower correlations with tree cover measurements using the line-point intercept method (r = 0.85 for ENVI, 0.83 for Feature AnalystTM, and 0.83 for eCognition. All software packages accurately and inexpensively extracted P-J canopy cover from NAIP imagery when the imagery was not blurred, and when P-J cover was not mixed with Amelanchier alnifolia (Utah serviceberry and Quercus gambelii (Gambel’s oak, which had similar spectral values as P-J.

  14. Optimizing continuous cover management of boreal forest when timber prices and tree growth are stochastic

    Directory of Open Access Journals (Sweden)

    Timo Pukkala

    2015-03-01

    Full Text Available Background Decisions on forest management are made under risk and uncertainty because the stand development cannot be predicted exactly and future timber prices are unknown. Deterministic calculations may lead to biased advice on optimal forest management. The study optimized continuous cover management of boreal forest in a situation where tree growth, regeneration, and timber prices include uncertainty. Methods Both anticipatory and adaptive optimization approaches were used. The adaptive approach optimized the reservation price function instead of fixed cutting years. The future prices of different timber assortments were described by cross-correlated auto-regressive models. The high variation around ingrowth model was simulated using a model that describes the cross- and autocorrelations of the regeneration results of different species and years. Tree growth was predicted with individual tree models, the predictions of which were adjusted on the basis of a climate-induced growth trend, which was stochastic. Residuals of the deterministic diameter growth model were also simulated. They consisted of random tree factors and cross- and autocorrelated temporal terms. Results Of the analyzed factors, timber price caused most uncertainty in the calculation of the net present value of a certain management schedule. Ingrowth and climate trend were less significant sources of risk and uncertainty than tree growth. Stochastic anticipatory optimization led to more diverse post-cutting stand structures than obtained in deterministic optimization. Cutting interval was shorter when risk and uncertainty were included in the analyses. Conclusions Adaptive optimization and management led to 6%–14% higher net present values than obtained in management that was based on anticipatory optimization. Increasing risk aversion of the forest landowner led to earlier cuttings in a mature stand. The effect of risk attitude on optimization results was small.

  15. Experimental tree removal in tallgrass prairie: variable responses of flora and fauna along a woody cover gradient.

    Science.gov (United States)

    Alford, Aaron L; Hellgren, Eric C; Limb, Ryan; Engle, David M

    2012-04-01

    Woody plant encroachment is a worldwide phenomenon in grassland and savanna systems whose consequence is often the development of an alternate woodland state. Theoretically, an alternate state may be associated with changes in system state variables (e.g., species composition) or abiotic parameter shifts (e.g., nutrient availability). When state-variable changes are cumulative, such as in woody plant encroachment, the probability of parameter shifts increases as system feedbacks intensify over time. Using a Before-After Control-Impact (BACI) design, we studied eight pairs of grassland sites undergoing various levels of eastern redcedar (Juniperus virginiana) encroachment to determine whether responses of flora and fauna to experimental redcedar removal differed according to the level of pretreatment redcedar cover. In the first year after removal, herbaceous plant species diversity and evenness, woody plant evenness, and invertebrate family richness increased linearly with pretreatment redcedar cover, whereas increases in small-mammal diversity and evenness were described by logarithmic trends. In contrast, increases in woody plant diversity and total biomass of terrestrial invertebrates were accentuated at levels of higher pretreatment cover. Tree removal also shifted small-mammal species composition toward a more grassland-associated assemblage. During the second year postremoval, increases in herbaceous plant diversity followed a polynomial trend, but increases in most other metrics did not vary along the pretreatment cover gradient. These changes were accompanied by extremely high growing-season precipitation, which may have homogenized floral and faunal responses to removal. Our results demonstrate that tree removal increases important community metrics among grassland flora and fauna within two years, with some responses to removal being strongly influenced by the stage of initial encroachment and modulated by climatic variability. Our results underscore the

  16. Continuous fields of land cover for the conterminous United States using Landsat data: First results from the Web-Enabled Landsat Data (WELD) project

    Science.gov (United States)

    Hansen, M.C.; Egorov, Alexey; Roy, David P.; Potapov, P.; Ju, J.; Turubanova, S.; Kommareddy, I.; Loveland, Thomas R.

    2011-01-01

    Vegetation Continuous Field (VCF) layers of 30 m percent tree cover, bare ground, other vegetation and probability of water were derived for the conterminous United States (CONUS) using Landsat 7 Enhanced Thematic Mapper Plus (ETM+) data sets from the Web-Enabled Landsat Data (WELD) project. Turnkey approaches to land cover characterization were enabled due to the systematic WELD Landsat processing, including conversion of digital numbers to calibrated top of atmosphere reflectance and brightness temperature, cloud masking, reprojection into a continental map projection and temporal compositing. Annual, seasonal and monthly WELD composites for 2008 were used as spectral inputs to a bagged regression and classification tree procedure using a large training data set derived from very high spatial resolution imagery and available ancillary data. The results illustrate the ability to perform Landsat land cover characterizations at continental scales that are internally consistent while retaining local spatial and thematic detail.

  17. CRED Cumulative Map of Percent Scleractinian Coral Cover at Kure Atoll, 2002-2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  18. CRED Cumulative Map of Percent Scleractinian Coral Cover at Laysan Island, 2002-2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  19. CRED Cumulative Map of Percent Scleractinian Coral Cover at Palmyra Atoll, 2002-2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  20. CRED Cumulative Map of Percent Scleractinian Coral Cover at Lisianski Island, 2001-2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  1. CRED Cumulative Map of Percent Scleractinian Coral Cover at Maro Reef, 2001-2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  2. CRED Cumulative Map of Percent Scleractinian Coral Cover at Baker Island, 2002-2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  3. Cobalt accumulation and circulation by blackgum trees

    International Nuclear Information System (INIS)

    Thomas, W.A.

    1975-01-01

    Blackgum (Nyssa sylvatica Marsh.) trees accumulate far greater concentrations of cobalt in mature foliage than do other species on the same site (363 ppM in ash of blackgum, compared with about 3 ppM by mockernut hickory and about 1 ppM by red maple, tulip tree, and white oak). Cobalt concentrations in dormant woody tissues of blackgum also significantly exceed those in the other four species. Inoculation of six blackgums with 60 Co revealed that cobalt remains mobile in the trees for at least 3 years. Foliar concentrations of stable cobalt increase uniformly until senescence. In late August, foliage accounts for only 9 percent of total tree weight but 57 percent of total tree cobalt. Losses of cobalt from trees occur almost entirely by leaf abscission, and the loss rates of weight and cobalt from decomposing litter are similar. Retention of cobalt in the biologically active soil layers perpetuates zones of cobalt concentration created by this species in woodlands

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

    Science.gov (United States)

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

    2017-12-01

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

  5. Fault tree handbook

    International Nuclear Information System (INIS)

    Haasl, D.F.; Roberts, N.H.; Vesely, W.E.; Goldberg, F.F.

    1981-01-01

    This handbook describes a methodology for reliability analysis of complex systems such as those which comprise the engineered safety features of nuclear power generating stations. After an initial overview of the available system analysis approaches, the handbook focuses on a description of the deductive method known as fault tree analysis. The following aspects of fault tree analysis are covered: basic concepts for fault tree analysis; basic elements of a fault tree; fault tree construction; probability, statistics, and Boolean algebra for the fault tree analyst; qualitative and quantitative fault tree evaluation techniques; and computer codes for fault tree evaluation. Also discussed are several example problems illustrating the basic concepts of fault tree construction and evaluation

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

    Science.gov (United States)

    Robert E. Benson; Michael J. Gonsior

    1981-01-01

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

  7. 7 CFR 1410.9 - Conversion to trees.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Conversion to trees. 1410.9 Section 1410.9... Conversion to trees. An owner or operator who has entered into a CRP contract prior to November 28, 1990, may... permanent vegetative cover, from such cover to hardwood trees, (including alley cropping and riparian...

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

    Directory of Open Access Journals (Sweden)

    Bill Buffum

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

  9. Tree Rings: Timekeepers of the Past.

    Science.gov (United States)

    Phipps, R. L.; McGowan, J.

    One of a series of general interest publications on science issues, this booklet describes the uses of tree rings in historical and biological recordkeeping. Separate sections cover the following topics: dating of tree rings, dating with tree rings, tree ring formation, tree ring identification, sample collections, tree ring cross dating, tree…

  10. TREE SELECTING AND TREE RING MEASURING IN DENDROCHRONOLOGICAL INVESTIGATIONS

    Directory of Open Access Journals (Sweden)

    Sefa Akbulut

    2004-04-01

    Full Text Available Dendrochronology is a method of dating which makes use of the annual nature of tree growth. Dendrochronology may be divided into a number of subfields, each of which covers one or more aspects of the use of tree ring data: dendroclimatology, dendrogeomorphology, dendrohydrology, dendroecology, dendroarchaelogy, and dendrogylaciology. Basic of all form the analysis of the tree rings. The wood or tree rings can aid to dating past events about climatology, ecology, geology, hydrology. Dendrochronological studies are conducted either on increment cores or on discs. It may be seen abnormalities on tree rings during the measurement like that false rings, missing rings, reaction wood. Like that situation, increment cores must be extracted from four different sides of each tree and be studied as more as on tree.

  11. Transferability of decision trees for land cover classification in a ...

    African Journals Online (AJOL)

    This paper attempts to derive classification rules from training data of four Landsat-8 scenes by using the classification and regression tree (CART) implementation of the decision tree algorithm. The transferability of the ruleset was evaluated by classifying two adjacent scenes. The classification of the four mosaicked scenes ...

  12. School Designed To Use 80 Percent Less Energy

    Science.gov (United States)

    American School and University, 1975

    1975-01-01

    The new Terraset Elementary School in Reston, Virginia, uses earth as a cover for the roof area and for about 80 percent of the wall area. A heat recovery system will be used with solar collectors playing a primary role in heating and cooling. (Author/MLF)

  13. Spatio-temporal change in forest cover and carbon storage considering actual and potential forest cover in South Korea.

    Science.gov (United States)

    Nam, Kijun; Lee, Woo-Kyun; Kim, Moonil; Kwak, Doo-Ahn; Byun, Woo-Hyuk; Yu, Hangnan; Kwak, Hanbin; Kwon, Taesung; Sung, Joohan; Chung, Dong-Jun; Lee, Seung-Ho

    2015-07-01

    This study analyzes change in carbon storage by applying forest growth models and final cutting age to actual and potential forest cover for six major tree species in South Korea. Using National Forest Inventory data, the growth models were developed to estimate mean diameter at breast height, tree height, and number of trees for Pinus densiflora, Pinus koraiensis, Pinus rigida, Larix kaempferi, Castanea crenata and Quercus spp. stands. We assumed that actual forest cover in a forest type map will change into potential forest covers according to the Hydrological and Thermal Analogy Groups model. When actual forest cover reaches the final cutting age, forest volume and carbon storage are estimated by changed forest cover and its growth model. Forest volume between 2010 and 2110 would increase from 126.73 to 157.33 m(3) hm(-2). Our results also show that forest cover, volume, and carbon storage could abruptly change by 2060. This is attributed to the fact that most forests are presumed to reach final cutting age. To avoid such dramatic change, a regeneration and yield control scheme should be prepared and implemented in a way that ensures balance in forest practice and yield.

  14. Impact of plant cover on fitness and behavioural traits of captive red-eyed tree frogs (Agalychnis callidryas.

    Directory of Open Access Journals (Sweden)

    Christopher J Michaels

    Full Text Available Despite the importance of ex situ conservation programmes as highlighted in the Amphibian Conservation Action Plan, there are few empirical studies that examine the influence of captive conditions on the fitness of amphibians, even for basic components of enclosure design such as cover provision. Maintaining the fitness of captive amphibian populations is essential to the success of ex situ conservation projects. Here we examined the impact of plant cover on measures of fitness and behaviour in captive red-eyed tree frogs (Agalychnis callidryas. We found significant effects of plant provision on body size, growth rates and cutaneous bacterial communities that together demonstrate a compelling fitness benefit from cover provision. We also demonstrate a strong behavioural preference for planted rather than non-planted areas. We also assessed the impact of plant provision on the abiotic environment in the enclosure as a potential driver of these behavioural and fitness effects. Together this data provides valuable information regarding enclosure design for a non-model amphibian species and has implications for amphibian populations maintained in captivity for conservation breeding programmes and research.

  15. Classification and regression trees

    CERN Document Server

    Breiman, Leo; Olshen, Richard A; Stone, Charles J

    1984-01-01

    The methodology used to construct tree structured rules is the focus of this monograph. Unlike many other statistical procedures, which moved from pencil and paper to calculators, this text's use of trees was unthinkable before computers. Both the practical and theoretical sides have been developed in the authors' study of tree methods. Classification and Regression Trees reflects these two sides, covering the use of trees as a data analysis method, and in a more mathematical framework, proving some of their fundamental properties.

  16. A framework for reporting tree cover attributes in agricultural landscapes

    Science.gov (United States)

    Dacia M. Meneguzzo; Greg C. Liknes

    2012-01-01

    The definition of forest land used by the USDA Forest Service’s Forest Inventory and Analysis program includes area, width, and density requirements. These requirements frequently exclude from the inventory any trees occupyingnarrow riparian corridors or linear tree plantings (e.g., windbreaks and shelterbelts). With recent attention being paid to such topics as bio-...

  17. Physical and chemical properties of slash pine tree parts

    Science.gov (United States)

    E. T. Howard

    1973-01-01

    In three 22-year-old slash pines from an unthinned plantation in central Louisiana, stemwood comprised 58.5 percent of total ovendry tree weight. Stumps and main roots made up 16.5 percent, bark 12.5, top of bole 5.0, needles 4.0, and branches 3.5. This material now is largely wasted when a tree is harvested; methods of utilizing it would extend fiber supplies by 70...

  18. The impact of tree age on biomass growth and carbon accumulation capacity: A retrospective analysis using tree ring data of three tropical tree species grown in natural forests of Suriname.

    Science.gov (United States)

    Köhl, Michael; Neupane, Prem R; Lotfiomran, Neda

    2017-01-01

    The world's forests play a pivotal role in the mitigation of global climate change. By photosynthesis they remove CO2 from the atmosphere and store carbon in their biomass. While old trees are generally acknowledged for a long carbon residence time, there is no consensus on their contribution to carbon accumulation due to a lack of long-term individual tree data. Tree ring analyses, which use anatomical differences in the annual formation of wood for dating growth zones, are a retrospective approach that provides growth patterns of individual trees over their entire lifetime. We developed time series of diameter growth and related annual carbon accumulation for 61 trees of the species Cedrela odorata L. (Meliacea), Hymenaea courbaril L. (Fabacea) and Goupia glabra Aubl. (Goupiacea). The trees grew in unmanaged tropical wet-forests of Suriname and reached ages from 84 to 255 years. Most of the trees show positive trends of diameter growth and carbon accumulation over time. For some trees we observed fluctuating growth-periods of lower growth alternate with periods of increased growth. In the last quarter of their lifetime trees accumulate on average between 39 percent (C. odorata) and 50 percent (G. glabra) of their final carbon stock. This suggests that old-growth trees in tropical forests do not only contribute to carbon stocks by long carbon resistance times, but maintain high rates of carbon accumulation at later stages of their life time.

  19. The Regional Land Cover Monitoring System: Building regional capacity through innovative land cover mapping approaches

    Science.gov (United States)

    Saah, D.; Tenneson, K.; Hanh, Q. N.; Aekakkararungroj, A.; Aung, K. S.; Goldstein, J.; Cutter, P. G.; Maus, P.; Markert, K. N.; Anderson, E.; Ellenburg, W. L.; Ate, P.; Flores Cordova, A. I.; Vadrevu, K.; Potapov, P.; Phongsapan, K.; Chishtie, F.; Clinton, N.; Ganz, D.

    2017-12-01

    Earth observation and Geographic Information System (GIS) tools, products, and services are vital to support the environmental decision making by governmental institutions, non-governmental agencies, and the general public. At the heart of environmental decision making is the monitoring land cover and land use change (LCLUC) for land resource planning and for ecosystem services, including biodiversity conservation and resilience to climate change. A major challenge for monitoring LCLUC in developing regions, such as Southeast Asia, is inconsistent data products at inconsistent intervals that have different typologies across the region and are typically made in without stakeholder engagement or input. Here we present the Regional Land Cover Monitoring System (RLCMS), a novel land cover mapping effort for Southeast Asia, implemented by SERVIR-Mekong, a joint NASA-USAID initiative that brings Earth observations to improve environmental decision making in developing countries. The RLCMS focuses on mapping biophysical variables (e.g. canopy cover, tree height, or percent surface water) at an annual interval and in turn using those biophysical variables to develop land cover maps based on stakeholder definitions of land cover classes. This allows for flexible and consistent land cover classifications that can meet the needs of different institutions across the region. Another component of the RLCMS production is the stake-holder engagement through co-development. Institutions that directly benefit from this system have helped drive the development for regional needs leading to services for their specific uses. Examples of services for regional stakeholders include using the RLCMS to develop maps using the IPCC classification scheme for GHG emission reporting and developing custom annual maps as an input to hydrologic modeling/flood forecasting systems. In addition to the implementation of this system and the service stemming from the RLCMS in Southeast Asia, it is

  20. Tree and shrub expansion over the past 34 years at the tree-line near Abisko, Sweden.

    Science.gov (United States)

    Rundqvist, Sara; Hedenås, Henrik; Sandström, Anneli; Emanuelsson, Urban; Eriksson, Håkan; Jonasson, Christer; Callaghan, Terry V

    2011-09-01

    Shrubs and trees are expected to expand in the sub-Arctic due to global warming. Our study was conducted in Abisko, sub-arctic Sweden. We recorded the change in coverage of shrub and tree species over a 32- to 34-year period, in three 50 x 50 m plots; in the alpine-tree-line ecotone. The cover of shrubs and trees (tree stems (> or =3.5 cm) were noted and positions determined. There has been a substantial increase of cover of shrubs and trees, particularly dwarf birch (Betula nana), and mountain birch (Betula pubescens ssp. czerepanovii), and an establishment of aspen (Populus tremula). The other species willows (Salix spp.), juniper (Juniperus communis), and rowan (Sorbus aucuparia) revealed inconsistent changes among the plots. Although this study was unable to identify the causes for the change in shrubs and small trees, they are consistent with anticipated changes due to climate change and reduced herbivory.

  1. Skewed Binary Search Trees

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølting; Moruz, Gabriel

    2006-01-01

    It is well-known that to minimize the number of comparisons a binary search tree should be perfectly balanced. Previous work has shown that a dominating factor over the running time for a search is the number of cache faults performed, and that an appropriate memory layout of a binary search tree...... can reduce the number of cache faults by several hundred percent. Motivated by the fact that during a search branching to the left or right at a node does not necessarily have the same cost, e.g. because of branch prediction schemes, we in this paper study the class of skewed binary search trees....... For all nodes in a skewed binary search tree the ratio between the size of the left subtree and the size of the tree is a fixed constant (a ratio of 1/2 gives perfect balanced trees). In this paper we present an experimental study of various memory layouts of static skewed binary search trees, where each...

  2. Alternative cover design

    International Nuclear Information System (INIS)

    1988-11-01

    The special study on Alternative Cover Designs is one of several studies initiated by the US Department of Energy (DOE) in response to the proposed US Environmental Protection Agency (EPA) groundwater standards. The objective of this study is to investigate the possibility of minimizing the infiltration of precipitation through stabilized tailings piles by altering the standard design of covers currently used on the Uranium Mill Tailings Remedial Action (UMTRA) Project. Prior. to the issuance of the proposed standards, UMTRA Project piles had common design elements to meet the required criteria, the most important of which were for radon diffusion, long-term stability, erosion protection, and groundwater protection. The standard pile covers consisted of three distinct layers. From top to bottom they were: rock for erosion protection; a sand bedding layer; and the radon barrier, usually consisting of a clayey sand material, which also functioned to limit infiltration into the tailings. The piles generally had topslopes from 2 to 4 percent and sideslopes of 20 percent

  3. Snow cover and temperature relationships in North America and Eurasia

    Science.gov (United States)

    Foster, J.; Owe, M.; Rango, A.

    1983-01-01

    In this study the snow cover extent during the autumn months in both North America and Eurasia has been related to the ensuing winter temperature as measured at several locations near the center of each continent. The relationship between autumn snow cover and the ensuing winter temperatures was found to be much better for Eurasia than for North America. For Eurasia the average snow cover extent during the autumn explained as much as 52 percent of the variance in the winter (December-February) temperatures compared to only 12 percent for North America. However, when the average winter snow cover was correlated with the average winter temperature it was found that the relationship was better for North America than for Eurasia. As much as 46 percent of the variance in the winter temperature was explained by the winter snow cover in North America compared to only 12 percent in Eurasia.

  4. CRED Cumulative Map of Percent Scleractinian Coral Cover at Pearl and Hermes Atoll, 2002-2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry.

  5. Atmospheric carbon reduction by urban trees

    International Nuclear Information System (INIS)

    Nowak, D.J.

    1993-01-01

    Trees, because they sequester atmospheric carbon through their growth process and conserve energy in urban areas, have been suggested as one means to combat increasing levels of atmospheric carbon. Analysis of the urban forest in Oakland, California (21% tree cover), reveals a tree carbon storage level of 11·0 metric tons/hectare. Trees in the area of the 1991 fire in Oakland stored approximately 14,500 metric tons of carbon, 10% of the total amount stored by Oakland's urban forest. National urban forest carbon storage in the United States (28% tree cover) is estimated at between 350 and 750 million metric tons. Establishment of 10 million urban trees annually over the next 10 years is estimated to sequester and offset the production of 363 million metric tons of carbon over the next 50 years-less than 1% of the estimated carbon emissions in the United States over the same time period. Advantages and limitations of managing urban trees to reduce atmospheric carbon are discussed. 36 refs., 2 figs., 3 tabs

  6. Non-phytoseiid Mesostigmata within citrus orchards in Florida: species distribution, relative and seasonal abundance within trees, associated vines and ground cover plants and additional collection records of mites in citrus orchards.

    Science.gov (United States)

    Childers, Carl C; Ueckermann, Eduard A

    2015-03-01

    Seven citrus orchards on reduced- to no-pesticide spray programs in central and south central Florida were sampled for non-phytoseiid mesostigmatid mites. Inner and outer canopy leaves, fruits, twigs and trunk scrapings were sampled monthly between August 1994 and January 1996. Open flowers were sampled in March from five of the sites. A total of 431 samples from one or more of 82 vine or ground cover plants were sampled monthly in five of the seven orchards. Two of the seven orchards (Mixon I and II) were on full herbicide programs and vines and ground cover plants were absent. A total of 2,655 mites (26 species) within the families: Ascidae, Blattisociidae, Laelapidae, Macrochelidae, Melicharidae, Pachylaelapidae and Parasitidae were identified. A total of 685 mites in the genus Asca (nine species: family Ascidae) were collected from within tree samples, 79 from vine or ground cover plants. Six species of Blattisociidae were collected: Aceodromus convolvuli, Blattisocius dentriticus, B. keegani, Cheiroseius sp. near jamaicensis, Lasioseius athiashenriotae and L. dentatus. A total of 485 Blattisociidae were collected from within tree samples compared with 167 from vine or ground cover plants. Low numbers of Laelapidae and Macrochelidae were collected from within tree samples. One Zygoseius furciger (Pachylaelapidae) was collected from Eleusine indica. Four species of Melicharidae were identified from 34 mites collected from within tree samples and 1,190 from vine or ground cover plants: Proctolaelaps lobatus was the most abundant species with 1,177 specimens collected from seven ground cover plants. One Phorytocarpais fimetorum (Parasitidae) was collected from inner leaves and four from twigs. Species of Ascidae, Blattisociidae, Melicharidae, Laelapidae and Pachylaelapidae were collected from 31 of the 82 vine or ground cover plants sampled, representing only a small fraction of the total number of Phytoseiidae collected from the same plants. Including the

  7. Arthropod but not bird predation in ethiopian homegardens is higher in tree-poor than in tree-rich landscapes.

    Science.gov (United States)

    Lemessa, Debissa; Hambäck, Peter A; Hylander, Kristoffer

    2015-01-01

    Bird and arthropod predation is often associated with natural pest control in agricultural landscapes, but the rates of predation may vary with the amount of tree cover or other environmental factors. We examined bird and arthropod predation in three tree-rich and three tree-poor landscapes across southwestern Ethiopia. Within each landscape we selected three tree-rich and three tree-poor homegardens in which we recorded the number of tree species and tree stems within 100 × 100 m surrounding the central house. To estimate predation rates, we attached plasticine caterpillars on leaves of two coffee and two avocado shrubs in each homegarden, and recorded the number of attacked caterpillars for 7-9 consecutive weeks. The overall mean daily predation rate was 1.45% for birds and 1.60% for arthropods. The rates of arthropod predation varied among landscapes and were higher in tree-poor landscapes. There was no such difference for birds. Within landscapes, predation rates from birds and arthropods did not vary between tree-rich and tree-poor homegardens in either tree-rich or tree-poor landscapes. The most surprising result was the lack of response by birds to tree cover at either spatial scale. Our results suggest that in tree-poor landscapes there are still enough non-crop habitats to support predatory arthropods and birds to deliver strong top-down effect on crop pests.

  8. Arthropod but not bird predation in ethiopian homegardens is higher in tree-poor than in tree-rich landscapes.

    Directory of Open Access Journals (Sweden)

    Debissa Lemessa

    Full Text Available Bird and arthropod predation is often associated with natural pest control in agricultural landscapes, but the rates of predation may vary with the amount of tree cover or other environmental factors. We examined bird and arthropod predation in three tree-rich and three tree-poor landscapes across southwestern Ethiopia. Within each landscape we selected three tree-rich and three tree-poor homegardens in which we recorded the number of tree species and tree stems within 100 × 100 m surrounding the central house. To estimate predation rates, we attached plasticine caterpillars on leaves of two coffee and two avocado shrubs in each homegarden, and recorded the number of attacked caterpillars for 7-9 consecutive weeks. The overall mean daily predation rate was 1.45% for birds and 1.60% for arthropods. The rates of arthropod predation varied among landscapes and were higher in tree-poor landscapes. There was no such difference for birds. Within landscapes, predation rates from birds and arthropods did not vary between tree-rich and tree-poor homegardens in either tree-rich or tree-poor landscapes. The most surprising result was the lack of response by birds to tree cover at either spatial scale. Our results suggest that in tree-poor landscapes there are still enough non-crop habitats to support predatory arthropods and birds to deliver strong top-down effect on crop pests.

  9. Ground cover in old-growth forests of the central hardwood region

    Science.gov (United States)

    Martin A. Spetich; Stephen R. Shifley; George R. Parker; Felix, Jr. Ponder

    1997-01-01

    Differences in ground cover (percent cover of litter, percent cover of vegetation and litter weight) in old-growth forests across this region are not well understood. We initiated a long-term study in a three-state region to enhance knowledge in this area. We present baseline results for ground cover and compare these data across productivity regions. Thirty 0.25-ac (0...

  10. Map of percent scleractinian coral cover and sand along camera tow tracks in west Hawaii

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral and sand overlaid on bathymetry and landsat imagery northwest...

  11. Coral Diseases Following Massive Bleaching in 2005 Cause 60 Percent Decline in Coral Cover and Mortality of the Threatened Species, Acropora Palmata, on Reefs in the U.S. Virgin Islands

    Science.gov (United States)

    Rogers, Caroline S.

    2008-01-01

    Record-high seawater temperatures and calm seas in the summer of 2005 led to the most severe coral bleaching (greater than 90 percent bleached coral cover) ever observed in the U.S. Virgin Islands (USVI) (figs. 1 and 2). All but a few coral species bleached, including the threatened species, Acropora palmata. Bleaching was seen from the surface to depths over 20 meters.

  12. EnviroAtlas - Percent Urban Land Cover by 12-Digit HUC for the Conterminous United States

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the percent urban land for each 12-digit hydrologic unit code (HUC) in the conterminous United States. For the purposes of this...

  13. Human action analysis with randomized trees

    CERN Document Server

    Yu, Gang; Liu, Zicheng

    2014-01-01

    This book will provide a comprehensive overview on human action analysis with randomized trees. It will cover both the supervised random trees and the unsupervised random trees. When there are sufficient amount of labeled data available, supervised random trees provides a fast method for space-time interest point matching. When labeled data is minimal as in the case of example-based action search, unsupervised random trees is used to leverage the unlabelled data. We describe how the randomized trees can be used for action classification, action detection, action search, and action prediction.

  14. Using a remote sensing-based, percent tree cover map to enhance forest inventory estimation

    Science.gov (United States)

    Ronald E. McRoberts; Greg C. Liknes; Grant M. Domke

    2014-01-01

    For most national forest inventories, the variables of primary interest to users are forest area and growing stock volume. The precision of estimates of parameters related to these variables can be increased using remotely sensed auxiliary variables, often in combination with stratified estimators. However, acquisition and processing of large amounts of remotely sensed...

  15. [Effects of sand-covering on apple trees transpiration and fruit quality in dry land orchards of Longdong, Gansu].

    Science.gov (United States)

    Zhang, Kun; Yin, Xiao-ning; Liu, Xiao-yong; Wang, Fa-lin

    2010-11-01

    Aiming at the seasonal drought in the dry land orchards of Longdong, Gansu Province, a sand-covering experiment was conducted with 15-year-old Nagafu No. 2 apple trees, with the soil water content, temperature, stem sap flow velocity, leaf stomatal conductance, and fruit quality measured. In the orchard covered with 5-cm-thick riversand, the increment of soil temperature in February-April was lower than 1 degrees C, while in June-July, it was 2.44 degrees C and 2.61 degrees C on sunny and cloudy days, respectively. The soil water content was over 60% of field capacity throughout the growing season. On sunny days with high soil water content (H season), the stem sap flow curve presented a wide peak. Under sand- covering, the sap flow started 0.6 h earlier, and the maximum sap flow velocity was 25.5% higher than the control. On cloudy days of H season, the maximum sap flow velocity was 165.6% higher than the control. On sunny days with low soil water content (L season), the sap flow curve had a single peak, and under sand covering, the sap flow started 0.5-1 h earlier than the control on sunny days. The maximum sap flow velocity was 794 g x h(-1). On cloudy days of L season, the sap flow started 1 h earlier, and the maximum sap flow velocity was 311.0% higher than the control. The evaporation of the control was 156.0% higher than that of sand-covering from March to July, suggesting that excessive ground water evaporation was the main reason to cause soil drought. Under sand-covering, single fruit mass was improved obviously whereas fruit firmness was reduced slightly, and soluble solids, vitamin C, total sugar, and organic acid contents were somewhat promoted.

  16. Learning from examples - Generation and evaluation of decision trees for software resource analysis

    Science.gov (United States)

    Selby, Richard W.; Porter, Adam A.

    1988-01-01

    A general solution method for the automatic generation of decision (or classification) trees is investigated. The approach is to provide insights through in-depth empirical characterization and evaluation of decision trees for software resource data analysis. The trees identify classes of objects (software modules) that had high development effort. Sixteen software systems ranging from 3,000 to 112,000 source lines were selected for analysis from a NASA production environment. The collection and analysis of 74 attributes (or metrics), for over 4,700 objects, captured information about the development effort, faults, changes, design style, and implementation style. A total of 9,600 decision trees were automatically generated and evaluated. The trees correctly identified 79.3 percent of the software modules that had high development effort or faults, and the trees generated from the best parameter combinations correctly identified 88.4 percent of the modules on the average.

  17. Fertilization increases diameter growth of birch-beech-maple trees in New Hampshire

    Science.gov (United States)

    L. O. Safford

    1973-01-01

    In a 60-year-old northern hardwood stand treated with lime plus NPK fertilizer, the following increases in average basal area growth rate over untreated trees were observed: sugar maple 128 percent, paper birch 69 percent, yellow birch 51 percent, and beech 20 percent. Magnitude of response was inversely related to relative growth rate of the species. Growth rate...

  18. EnviroAtlas - Milwaukee, WI - Estimated Tree Cover Along Busy Roads

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

  19. Which trees should be removed in thinning?

    Directory of Open Access Journals (Sweden)

    Timo Pukkala

    2015-12-01

    Full Text Available Background: In economically optimal management, trees that are removed in a thinning treatment should be selected on the basis of their value, relative value increment and the effect of removal on the growth of remaining trees. Large valuable trees with decreased value increment should be removed, especially when they overtop smaller trees. Methods: This study optimized the tree selection rule in the thinning treatments of continuous cover management when the aim is to maximize the profitability of forest management. The weights of three criteria (stem value, relative value increment and effect of removal on the competition of remaining trees were optimized together with thinning intervals. Results and conclusions: The results confirmed the hypothesis that optimal thinning involves removing predominantly large trees. Increasing stumpage value, decreasing relative value increment, and increasing competitive influence increased the likelihood that removal is optimal decision. However, if the spatial distribution of trees is irregular, it is optimal to leave large trees in sparse places and remove somewhat smaller trees from dense places. However, the benefit of optimal thinning, as compared to diameter limit cutting is not usually large in pure one-species stands. On the contrary, removing the smallest trees from the stand may lead to significant (30–40 % reductions in the net present value of harvest incomes. Keywords: Continuous cover forestry, Tree selection, High thinning, Optimal management, Spatial distribution, Spatial growth model

  20. Identifying Generalizable Image Segmentation Parameters for Urban Land Cover Mapping through Meta-Analysis and Regression Tree Modeling

    Directory of Open Access Journals (Sweden)

    Brian A. Johnson

    2018-01-01

    Full Text Available The advent of very high resolution (VHR satellite imagery and the development of Geographic Object-Based Image Analysis (GEOBIA have led to many new opportunities for fine-scale land cover mapping, especially in urban areas. Image segmentation is an important step in the GEOBIA framework, so great time/effort is often spent to ensure that computer-generated image segments closely match real-world objects of interest. In the remote sensing community, segmentation is frequently performed using the multiresolution segmentation (MRS algorithm, which is tuned through three user-defined parameters (the scale, shape/color, and compactness/smoothness parameters. The scale parameter (SP is the most important parameter and governs the average size of generated image segments. Existing automatic methods to determine suitable SPs for segmentation are scene-specific and often computationally intensive, so an approach to estimating appropriate SPs that is generalizable (i.e., not scene-specific could speed up the GEOBIA workflow considerably. In this study, we attempted to identify generalizable SPs for five common urban land cover types (buildings, vegetation, roads, bare soil, and water through meta-analysis and nonlinear regression tree (RT modeling. First, we performed a literature search of recent studies that employed GEOBIA for urban land cover mapping and extracted the MRS parameters used, the image properties (i.e., spatial and radiometric resolutions, and the land cover classes mapped. Using this data extracted from the literature, we constructed RT models for each land cover class to predict suitable SP values based on the: image spatial resolution, image radiometric resolution, shape/color parameter, and compactness/smoothness parameter. Based on a visual and quantitative analysis of results, we found that for all land cover classes except water, relatively accurate SPs could be identified using our RT modeling results. The main advantage of our

  1. A Comparative Study of Some Properties of Cassava and Tree Cassava Starch Films

    Science.gov (United States)

    Belibi, P. C.; Daou, T. J.; Ndjaka, J. M. B.; Nsom, B.; Michelin, L.; Durand, B.

    Cassava and tree cassava starch films plasticized with glycerol were produced by casting method. Different glycerol contents (30, 35, 40 and 45 wt. % on starch dry basis) were used and the resulting films were fully characterized. Their water barrier and mechanical properties were compared. While increasing glycerol concentration, moisture content, water solubility, water vapour permeability, tensile strength, percent elongation at break and Young's modulus decreased for both cassava and tree cassava films. Tree cassava films presented better values of water vapour permeability, water solubility and percent elongation at break compared to those of cassava films, regardless of the glycerol content.

  2. Suppression of nighttime sap flux with lower stem photosynthesis in Eucalyptus trees.

    Science.gov (United States)

    Gao, Jianguo; Zhou, Juan; Sun, Zhenwei; Niu, Junfeng; Zhou, Cuiming; Gu, Daxing; Huang, Yuqing; Zhao, Ping

    2016-04-01

    It is widely accepted that substantial nighttime sap flux (J s,n) or transpiration (E) occurs in most plants, but the physiological implications are poorly known. It has been hypothesized that J s,n or E serves to enhance nitrogen uptake or deliver oxygen; however, no clear evidence is currently available. In this study, sap flux (J s) in Eucalyptus grandis × urophylla with apparent stem photosynthesis was measured, including control trees which were covered by aluminum foil (approximately 1/3 of tree height) to block stem photosynthesis. We hypothesized that the nighttime water flux would be suppressed in trees with lower stem photosynthesis. The results showed that the green tissue degraded after 3 months, demonstrating a decrease in stem photosynthesis. The daytime J s decreased by 21.47%, while J s,n decreased by 12.03% in covered trees as compared to that of control, and the difference was statistically significant (P photosynthesis in covered trees. Predawn (ψ pd) of covered trees was marginally higher than that of control while lower at predawn stomatal conductance (g s), indicating a suppressed water flux in covered trees. There was no difference in leaf carbon content and δ(13)C between the two groups, while leaf nitrogen content and δ(15)N were significantly higher in covered trees than that of the control (P < 0.05), indicating that J s,n was not used for nitrogen uptake. These results suggest that J s,n may act as an oxygen pathway since green tissue has a higher respiration or oxygen demand than non-green tissue. Thus, this study demonstrated the physiological implications of J s,n and the possible benefits of nighttime water use or E by the tree.

  3. Land use and land cover mapping: City of Palm Bay, Florida

    Science.gov (United States)

    Barile, D. D.; Pierce, R.

    1977-01-01

    Two different computer systems were compared for use in making land use and land cover maps. The Honeywell 635 with the LANDSAT signature development program (LSDP) produced a map depicting general patterns, but themes were difficult to classify as specific land use. Urban areas were unclassified. The General Electric Image 100 produced a map depicting eight land cover categories classifying 68 percent of the total area. Ground truth, LSDP, and Image 100 maps were all made to the same scale for comparison. LSDP agreed with the ground truth 60 percent and 64 percent within the two test areas compared and Image 100 was in agreement 70 percent and 80 percent.

  4. Urban trees and the risk of poor birth outcomes

    Science.gov (United States)

    Geoffrey H. Donovan; Yvonne L. Michael; David T. Butry; Amy D. Sullivan; John M. Chase

    2011-01-01

    This paper investigated whether greater tree-canopy cover is associated with reduced risk of poor birth outcomes in Portland, Oregon. Residential addresses were geocoded and linked to classified-aerial imagery to calculate tree-canopy cover in 50, 100, and 200 m buffers around each home in our sample (n=5696). Detailed data on maternal characteristics and additional...

  5. HERB RECOVERY IN DEGRADED CAATINGA SITES ENRICHED WITH NATIVE TREES

    Directory of Open Access Journals (Sweden)

    Juliana Matos Figueiredo

    2017-01-01

    Full Text Available Herb recovery was evaluated in degraded Caatinga sites protected from grazing and enriched with native trees, in Patos-PB state, Brazil . Treatments were randomized according to a block design with five treatments (no tree planting –T 0 – or tree planting of three tree species in pure –T 1 = Poincianella pyramidalis , T 2 = Mimosa tenuiflora and T 3 = Cnidoscolus quercifolius – or mixed balanced stands –T 4 and five replications of squared-144-m 2 plots with 36 seedlings developing in planting holes enriched with manure and chemical fertilizers, arranged in a 2 m x 2 m grid. Data were collected from September 2008 to October 2009. After this period, natural tree regeneration was still not observed, and tree canopy covered 15 to 49% of the soil and did not affect herb growth and species composition. Initial and final herb cover were 16% and 100%, respectively. The number of dicot herbs increased from five, mainly two Sida species, to 13 species, monocots were represented by one species only (Aristida sp ., and quantity of herb forage reached 3 ton/ha (2:1, dicot:monocot. Adjacent overgrazed plots kept the initial low level of herb cover and species composition. Animal deferment during one year allowed the increase in soil cover and plant diversity in degraded Caatinga sites into which planted tree seedlings established successfully. This management practice could be implemented to avoid further environmental degradation and recover degraded areas.

  6. EnviroAtlas - Percent Stream Buffer Zone As Natural Land Cover for the Conterminous United States

    Science.gov (United States)

    This EnviroAtlas dataset shows the percentage of land area within a 30 meter buffer zone along the National Hydrography Dataset (NHD) high resolution stream network, and along water bodies such as lakes and ponds that are connected via flow to the streams, that is classified as forest land cover, modified forest land cover, and natural land cover using the 2006 National Land Cover Dataset (NLCD) for each Watershed Boundary Dataset (WBD) 12-digit hydrological unit (HUC) in the conterminous United States. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

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

    Science.gov (United States)

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

    2006-01-01

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

  8. Carbon storage and sequestration by trees in urban and community areas of the United States.

    Science.gov (United States)

    Nowak, David J; Greenfield, Eric J; Hoehn, Robert E; Lapoint, Elizabeth

    2013-07-01

    Carbon storage and sequestration by urban trees in the United States was quantified to assess the magnitude and role of urban forests in relation to climate change. Urban tree field data from 28 cities and 6 states were used to determine the average carbon density per unit of tree cover. These data were applied to statewide urban tree cover measurements to determine total urban forest carbon storage and annual sequestration by state and nationally. Urban whole tree carbon storage densities average 7.69 kg C m(-2) of tree cover and sequestration densities average 0.28 kg C m(-2) of tree cover per year. Total tree carbon storage in U.S. urban areas (c. 2005) is estimated at 643 million tonnes ($50.5 billion value; 95% CI = 597 million and 690 million tonnes) and annual sequestration is estimated at 25.6 million tonnes ($2.0 billion value; 95% CI = 23.7 million to 27.4 million tonnes). Published by Elsevier Ltd.

  9. Carbon storage and sequestration by trees in urban and community areas of the United States

    International Nuclear Information System (INIS)

    Nowak, David J.; Greenfield, Eric J.; Hoehn, Robert E.; Lapoint, Elizabeth

    2013-01-01

    Carbon storage and sequestration by urban trees in the United States was quantified to assess the magnitude and role of urban forests in relation to climate change. Urban tree field data from 28 cities and 6 states were used to determine the average carbon density per unit of tree cover. These data were applied to statewide urban tree cover measurements to determine total urban forest carbon storage and annual sequestration by state and nationally. Urban whole tree carbon storage densities average 7.69 kg C m −2 of tree cover and sequestration densities average 0.28 kg C m −2 of tree cover per year. Total tree carbon storage in U.S. urban areas (c. 2005) is estimated at 643 million tonnes ($50.5 billion value; 95% CI = 597 million and 690 million tonnes) and annual sequestration is estimated at 25.6 million tonnes ($2.0 billion value; 95% CI = 23.7 million to 27.4 million tonnes). -- Highlights: •Total tree carbon storage in U.S. urban areas (c. 2005) is estimated at 643 million tonnes. •Total tree carbon storage in U.S. urban and community areas is estimated at 1.36 billion tonnes. •Net carbon sequestration in U.S. urban areas varies by state and is estimated at 18.9 million tonnes per year. •Overlap between U.S. forest and urban forest carbon estimates is between 247 million and 303 million tonnes. -- Field and tree cover measurements reveal carbon storage and sequestration by trees in U.S. urban and community areas

  10. Effects of herbicide release on the growth of 8- to 12-year-old hardwood trees

    Science.gov (United States)

    G.W. Wendel; Neil I. Lamson; Neil I. Lamson

    1987-01-01

    In 8- to 12-year-old Appalachian hardwood stands, crop trees were released by stem injecting competing trees with a 20 percent aqueous solution of glyphosate. Species released were black cherry, red oak, and sugar maple. Release treatments were (a) injection of all trees within a 5-foot radius of the crop tree bole and (b) injections of all trees whose crown touched...

  11. NLCD 2001 - Tree Canopy

    Data.gov (United States)

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

  12. Rainfall and streamflow from small tree-covered and fern-covered and burned watersheds in Hawaii

    Science.gov (United States)

    H. W. Anderson; P. D. Duffy; Teruo Yamamoto

    1966-01-01

    Streamflow from two 30-acre watersheds near Honolulu was studied by using principal components regression analysis. Models using data on monthly, storm, and peak discharges were tested against several variables expressing amount and intensity of rainfall, and against variables expressing antecedent rainfall. Explained variation ranged from 78 to 94 percent. The...

  13. Land-cover change detection

    Science.gov (United States)

    Chen, Xuexia; Giri, Chandra; Vogelmann, James

    2012-01-01

    Land cover is the biophysical material on the surface of the earth. Land-cover types include grass, shrubs, trees, barren, water, and man-made features. Land cover changes continuously.  The rate of change can be either dramatic and abrupt, such as the changes caused by logging, hurricanes and fire, or subtle and gradual, such as regeneration of forests and damage caused by insects (Verbesselt et al., 2001).  Previous studies have shown that land cover has changed dramatically during the past sevearal centuries and that these changes have severely affected our ecosystems (Foody, 2010; Lambin et al., 2001). Lambin and Strahlers (1994b) summarized five types of cause for land-cover changes: (1) long-term natural changes in climate conditions, (2) geomorphological and ecological processes, (3) human-induced alterations of vegetation cover and landscapes, (4) interannual climate variability, and (5) human-induced greenhouse effect.  Tools and techniques are needed to detect, describe, and predict these changes to facilitate sustainable management of natural resources.

  14. Examination of the relationship between vegetation cover indices ...

    African Journals Online (AJOL)

    Therefore it is recommended that agroforestry and land scaping should be embraced in the area with emphasis on short economic trees with moderate crown cover that will allow crops or grasses to grow under it as well as avoid the negative impact of rain water drops from very tall tree that can cause soil erosion.

  15. Forest Cover Estimation in Ireland Using Radar Remote Sensing: A Comparative Analysis of Forest Cover Assessment Methodologies

    Science.gov (United States)

    Devaney, John; Barrett, Brian; Barrett, Frank; Redmond, John; O`Halloran, John

    2015-01-01

    Quantification of spatial and temporal changes in forest cover is an essential component of forest monitoring programs. Due to its cloud free capability, Synthetic Aperture Radar (SAR) is an ideal source of information on forest dynamics in countries with near-constant cloud-cover. However, few studies have investigated the use of SAR for forest cover estimation in landscapes with highly sparse and fragmented forest cover. In this study, the potential use of L-band SAR for forest cover estimation in two regions (Longford and Sligo) in Ireland is investigated and compared to forest cover estimates derived from three national (Forestry2010, Prime2, National Forest Inventory), one pan-European (Forest Map 2006) and one global forest cover (Global Forest Change) product. Two machine-learning approaches (Random Forests and Extremely Randomised Trees) are evaluated. Both Random Forests and Extremely Randomised Trees classification accuracies were high (98.1–98.5%), with differences between the two classifiers being minimal (forest area and an increase in overall accuracy of SAR-derived forest cover maps. All forest cover products were evaluated using an independent validation dataset. For the Longford region, the highest overall accuracy was recorded with the Forestry2010 dataset (97.42%) whereas in Sligo, highest overall accuracy was obtained for the Prime2 dataset (97.43%), although accuracies of SAR-derived forest maps were comparable. Our findings indicate that spaceborne radar could aid inventories in regions with low levels of forest cover in fragmented landscapes. The reduced accuracies observed for the global and pan-continental forest cover maps in comparison to national and SAR-derived forest maps indicate that caution should be exercised when applying these datasets for national reporting. PMID:26262681

  16. Mimusops elengi L. (Bulletwood tree; Hindi: Bakul or Maulsari) of ...

    Indian Academy of Sciences (India)

    Mimusops elengi L. (Bulletwood tree; Hindi: Bakul or Maulsari) of Sapotaceae is a handsome evergreen tree with milky latex and tender vegetative parts covered with brown hairs. The tree is often cultivated in parks and as an avenue tree. The fascicled flowers are small, white and sweet-scented. The ovoid berries are ...

  17. Land-cover effects on soil organic carbon stocks in a European city.

    Science.gov (United States)

    Edmondson, Jill L; Davies, Zoe G; McCormack, Sarah A; Gaston, Kevin J; Leake, Jonathan R

    2014-02-15

    Soil is the vital foundation of terrestrial ecosystems storing water, nutrients, and almost three-quarters of the organic carbon stocks of the Earth's biomes. Soil organic carbon (SOC) stocks vary with land-cover and land-use change, with significant losses occurring through disturbance and cultivation. Although urbanisation is a growing contributor to land-use change globally, the effects of urban land-cover types on SOC stocks have not been studied for densely built cities. Additionally, there is a need to resolve the direction and extent to which greenspace management such as tree planting impacts on SOC concentrations. Here, we analyse the effect of land-cover (herbaceous, shrub or tree cover), on SOC stocks in domestic gardens and non-domestic greenspaces across a typical mid-sized U.K. city (Leicester, 73 km(2), 56% greenspace), and map citywide distribution of this ecosystem service. SOC was measured in topsoil and compared to surrounding extra-urban agricultural land. Average SOC storage in the city's greenspace was 9.9 kg m(-2), to 21 cm depth. SOC concentrations under trees and shrubs in domestic gardens were greater than all other land-covers, with total median storage of 13.5 kg m(-2) to 21 cm depth, more than 3 kg m(-2) greater than any other land-cover class in domestic and non-domestic greenspace and 5 kg m(-2) greater than in arable land. Land-cover did not significantly affect SOC concentrations in non-domestic greenspace, but values beneath trees were higher than under both pasture and arable land, whereas concentrations under shrub and herbaceous land-covers were only higher than arable fields. We conclude that although differences in greenspace management affect SOC stocks, trees only marginally increase these stocks in non-domestic greenspaces, but may enhance them in domestic gardens, and greenspace topsoils hold substantial SOC stores that require protection from further expansion of artificial surfaces e.g. patios and driveways. Copyright

  18. Measuring urban tree loss dynamics across residential landscapes.

    Science.gov (United States)

    Ossola, Alessandro; Hopton, Matthew E

    2018-01-15

    The spatial arrangement of urban vegetation depends on urban morphology and socio-economic settings. Urban vegetation changes over time because of human management. Urban trees are removed due to hazard prevention or aesthetic preferences. Previous research attributed tree loss to decreases in canopy cover. However, this provides little information about location and structural characteristics of trees lost, as well as environmental and social factors affecting tree loss dynamics. This is particularly relevant in residential landscapes where access to residential parcels for field surveys is limited. We tested whether multi-temporal airborne LiDAR and multi-spectral imagery collected at a 5-year interval can be used to investigate urban tree loss dynamics across residential landscapes in Denver, CO and Milwaukee, WI, covering 400,705 residential parcels in 444 census tracts. Position and stem height of trees lost were extracted from canopy height models calculated as the difference between final (year 5) and initial (year 0) vegetation height derived from LiDAR. Multivariate regression models were used to predict number and height of tree stems lost in residential parcels in each census tract based on urban morphological and socio-economic variables. A total of 28,427 stems were lost from residential parcels in Denver and Milwaukee over 5years. Overall, 7% of residential parcels lost one stem, averaging 90.87 stems per km 2 . Average stem height was 10.16m, though trees lost in Denver were taller compared to Milwaukee. The number of stems lost was higher in neighborhoods with higher canopy cover and developed before the 1970s. However, socio-economic characteristics had little effect on tree loss dynamics. The study provides a simple method for measuring urban tree loss dynamics within and across entire cities, and represents a further step toward high resolution assessments of the three-dimensional change of urban vegetation at large spatial scales. Published by

  19. EnviroAtlas Tree Cover Configuration and Connectivity, Water Background Web Service

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas web service supports research and online mapping activities related to EnviroAtlas (https://www.epa.gov/enviroatlas). The 1-meter resolution tree...

  20. Monitoring Urban Tree Cover Using Object-Based Image Analysis and Public Domain Remotely Sensed Data

    Directory of Open Access Journals (Sweden)

    Meghan Halabisky

    2011-10-01

    Full Text Available Urban forest ecosystems provide a range of social and ecological services, but due to the heterogeneity of these canopies their spatial extent is difficult to quantify and monitor. Traditional per-pixel classification methods have been used to map urban canopies, however, such techniques are not generally appropriate for assessing these highly variable landscapes. Landsat imagery has historically been used for per-pixel driven land use/land cover (LULC classifications, but the spatial resolution limits our ability to map small urban features. In such cases, hyperspatial resolution imagery such as aerial or satellite imagery with a resolution of 1 meter or below is preferred. Object-based image analysis (OBIA allows for use of additional variables such as texture, shape, context, and other cognitive information provided by the image analyst to segment and classify image features, and thus, improve classifications. As part of this research we created LULC classifications for a pilot study area in Seattle, WA, USA, using OBIA techniques and freely available public aerial photography. We analyzed the differences in accuracies which can be achieved with OBIA using multispectral and true-color imagery. We also compared our results to a satellite based OBIA LULC and discussed the implications of per-pixel driven vs. OBIA-driven field sampling campaigns. We demonstrated that the OBIA approach can generate good and repeatable LULC classifications suitable for tree cover assessment in urban areas. Another important finding is that spectral content appeared to be more important than spatial detail of hyperspatial data when it comes to an OBIA-driven LULC.

  1. Determinants of woody cover in African savannas

    Science.gov (United States)

    Sankaran, M.; Hanan, N.P.; Scholes, Robert J.; Ratnam, J.; Augustine, D.J.; Cade, B.S.; Gignoux, J.; Higgins, S.I.; Le, Roux X.; Ludwig, F.; Ardo, J.; Banyikwa, F.; Bronn, A.; Bucini, G.; Caylor, K.K.; Coughenour, M.B.; Diouf, A.; Ekaya, W.; Feral, C.J.; February, E.C.; Frost, P.G.H.; Hiernaux, P.; Hrabar, H.; Metzger, K.L.; Prins, H.H.T.; Ringrose, S.; Sea, W.; Tews, J.; Worden, J.; Zambatis, N.

    2005-01-01

    Savannas are globally important ecosystems of great significance to human economies. In these biomes, which are characterized by the co-dominance of trees and grasses, woody cover is a chief determinant of ecosystem properties 1-3. The availability of resources (water, nutrients) and disturbance regimes (fire, herbivory) are thought to be important in regulating woody cover1,2,4,5, but perceptions differ on which of these are the primary drivers of savanna structure. Here we show, using data from 854 sites across Africa, that maximum woody cover in savannas receiving a mean annual precipitation (MAP) of less than ???650 mm is constrained by, and increases linearly with, MAP. These arid and semi-arid savannas may be considered 'stable' systems in which water constrains woody cover and permits grasses to coexist, while fire, herbivory and soil properties interact to reduce woody cover below the MAP-controlled upper bound. Above a MAP of ???650 mm, savannas are 'unstable' systems in which MAP is sufficient for woody canopy closure, and disturbances (fire, herbivory) are required for the coexistence of trees and grass. These results provide insights into the nature of African savannas and suggest that future changes in precipitation 6 may considerably affect their distribution and dynamics. ?? 2005 Nature Publishing Group.

  2. National forest cover monitoring in mainland South and Southeast Asia: method development and capacity building

    Science.gov (United States)

    Tyukavina, A.; Potapov, P.; Hansen, M.; Talero, Y.; Turubanova, S.; Pickering, J.; Pickens, A. H.; Quyen, N. H.; Spirovska Kono, M.

    2017-12-01

    Timely forest monitoring data produced following good practice guidance are required for national reporting on greenhouse gas emissions, national forest resource assessments, and monitoring for REDD+ projects. Remote sensing provides a cost-efficient supplement to national forest inventories, and is often the single viable source of data on forest extent for countries still in the process of establishing field-based inventories. Operational forest monitoring using remotely sensed data requires technical capacity to store, process, and analyze high volumes of satellite imagery. The University of Maryland Global Land Analysis and Discovery (UMD GLAD) lab possesses such technical capacity and is seeking to transfer it to national agencies responsible for forest reporting, national academic institutions, and NGOs. Our projects in South and Southeast Asia include regional forest monitoring in the lower Mekong region in support of the Regional Land Cover Monitoring System (funded by the NASA SERVIR program) and building capacity for forest monitoring in Nepal, Bangladesh, Vietnam, Cambodia, Laos, and Thailand (funded by the SilvaCarbon program). Our forest monitoring approach is a regional scale adaptation of methods developed for the global analysis (Hansen et al. 2013). The methodology to track large-scale clearing of natural forests (e.g. in Brazil and Indonesia) is well established; however, the methods for small-scale disturbance mapping and tree cover rotation assessment are still in development. In Bangladesh our mapping of tree cover change between 2000-2014 revealed that 54% of the tree canopy cover was outside forests, and the majority of canopy changes were smaller than 0.1 ha. Landsat's 30-m resolution was therefore insufficient to monitor changes in tree cover. By using a probability sample of high resolution (circa 1 m) imagery we were able to quantify change in tree canopy cover outside forests (including village woodlots, tree plantations and agroforestry

  3. An evaluation of 10 percent and 20 percent benzocaine gels in patients with acute toothaches

    Science.gov (United States)

    Hersh, Elliot V.; Ciancio, Sebastian G.; Kuperstein, Arthur S.; Stoopler, Eric T.; Moore, Paul A.; Boynes, Sean G.; Levine, Steven C.; Casamassimo, Paul; Leyva, Rina; Mathew, Tanya; Shibly, Othman; Creighton, Paul; Jeffers, Gary E.; Corby, Patricia M.A.; Turetzky, Stanley N.; Papas, Athena; Wallen, Jillian; Idzik-Starr, Cynthia; Gordon, Sharon M.

    2013-01-01

    Background The authors evaluated the efficacy and tolerability of 10 percent and 20 percent benzocaine gels compared with those of a vehicle (placebo) gel for the temporary relief of toothache pain. They also assessed the compliance with the label dose administration directions on the part of participants with toothache pain. Methods Under double-masked conditions, 576 participants self-applied study gel to an open tooth cavity and surrounding oral tissues. Participants evaluated their pain intensity and pain relief for 120 minutes. The authors determined the amount of gel the participants applied. Results The responders’ rates (the primary efficacy parameter), defined as the percentage of participants who had an improvement in pain intensity as exhibited by a pain score reduction of at least one unit on the dental pain scale from baseline for two consecutive assessments any time between the five- and 20-minute points, were 87.3 percent, 80.7 percent and 70.4 percent, respectively, for 20 percent benzocaine gel, 10 percent benzocaine gel and vehicle gel. Both benzocaine gels were significantly (P ≤ .05) better than vehicle gel; the 20 percent benzocaine gel also was significantly (P ≤ .05) better than the 10 percent benzocaine gel. The mean amount of gel applied was 235.6 milligrams, with 88.2 percent of participants applying 400 mg or less. Conclusions Both 10 percent and 20 percent benzocaine gels were more efficacious than the vehicle gel, and the 20 percent benzocaine gel was more efficacious than the 10 percent benzocaine gel. All treatments were well tolerated by participants. Practical Implications Patients can use 10 percent and 20 percent benzocaine gels to temporarily treat toothache pain safely. PMID:23633700

  4. Minimum Covers of Fixed Cardinality in Weighted Graphs.

    Science.gov (United States)

    White, Lee J.

    Reported is the result of research on combinatorial and algorithmic techniques for information processing. A method is discussed for obtaining minimum covers of specified cardinality from a given weighted graph. By the indicated method, it is shown that the family of minimum covers of varying cardinality is related to the minimum spanning tree of…

  5. Evaluation of forest cover estimates for Haiti using supervised classification of Landsat data

    Science.gov (United States)

    Churches, Christopher E.; Wampler, Peter J.; Sun, Wanxiao; Smith, Andrew J.

    2014-08-01

    This study uses 2010-2011 Landsat Thematic Mapper (TM) imagery to estimate total forested area in Haiti. The thematic map was generated using radiometric normalization of digital numbers by a modified normalization method utilizing pseudo-invariant polygons (PIPs), followed by supervised classification of the mosaicked image using the Food and Agriculture Organization (FAO) of the United Nations Land Cover Classification System. Classification results were compared to other sources of land-cover data produced for similar years, with an emphasis on the statistics presented by the FAO. Three global land cover datasets (GLC2000, Globcover, 2009, and MODIS MCD12Q1), and a national-scale dataset (a land cover analysis by Haitian National Centre for Geospatial Information (CNIGS)) were reclassified and compared. According to our classification, approximately 32.3% of Haiti's total land area was tree covered in 2010-2011. This result was confirmed using an error-adjusted area estimator, which predicted a tree covered area of 32.4%. Standardization to the FAO's forest cover class definition reduces the amount of tree cover of our supervised classification to 29.4%. This result was greater than the reported FAO value of 4% and the value for the recoded GLC2000 dataset of 7.0%, but is comparable to values for three other recoded datasets: MCD12Q1 (21.1%), Globcover (2009) (26.9%), and CNIGS (19.5%). We propose that at coarse resolutions, the segmented and patchy nature of Haiti's forests resulted in a systematic underestimation of the extent of forest cover. It appears the best explanation for the significant difference between our results, FAO statistics, and compared datasets is the accuracy of the data sources and the resolution of the imagery used for land cover analyses. Analysis of recoded global datasets and results from this study suggest a strong linear relationship (R2 = 0.996 for tree cover) between spatial resolution and land cover estimates.

  6. Raccoon Use of Den Trees and Plant Associations in Western Mesophytic Forests: Tree Attributes and Availability or Landscape Heterogeneity?

    Science.gov (United States)

    Winston P. Smith; Keith M. Endres

    2012-01-01

    We monitored 15 radio-collared raccoons (Procyon lotor) on Davies Island in March 1987 - May 1988 to determine the extent to which individual tree attributes or spatial configuration of plant associations (habitat types) across the land-scape influenced den use. Of 1091 verified den sites, 428 were in tree cavities. Raccoon occurrence among 4 cover...

  7. P{owering 'Trees

    Indian Academy of Sciences (India)

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

  8. Using fragmentation trees and mass spectral trees for identifying unknown compounds in metabolomics.

    Science.gov (United States)

    Vaniya, Arpana; Fiehn, Oliver

    2015-06-01

    Identification of unknown metabolites is the bottleneck in advancing metabolomics, leaving interpretation of metabolomics results ambiguous. The chemical diversity of metabolism is vast, making structure identification arduous and time consuming. Currently, comprehensive analysis of mass spectra in metabolomics is limited to library matching, but tandem mass spectral libraries are small compared to the large number of compounds found in the biosphere, including xenobiotics. Resolving this bottleneck requires richer data acquisition and better computational tools. Multi-stage mass spectrometry (MSn) trees show promise to aid in this regard. Fragmentation trees explore the fragmentation process, generate fragmentation rules and aid in sub-structure identification, while mass spectral trees delineate the dependencies in multi-stage MS of collision-induced dissociations. This review covers advancements over the past 10 years as a tool for metabolite identification, including algorithms, software and databases used to build and to implement fragmentation trees and mass spectral annotations.

  9. Monitoring the Urban Tree Cover for Urban Ecosystem Services - The Case of Leipzig, Germany

    Science.gov (United States)

    Banzhaf, E.; Kollai, H.

    2015-04-01

    Urban dynamics such as (extreme) growth and shrinkage bring about fundamental challenges for urban land use and related changes. In order to achieve a sustainable urban development, it is crucial to monitor urban green infrastructure at microscale level as it provides various urban ecosystem services in neighbourhoods, supporting quality of life and environmental health. We monitor urban trees by means of a multiple data set to get a detailed knowledge on its distribution and change over a decade for the entire city. We have digital orthophotos, a digital elevation model and a digital surface model. The refined knowledge on the absolute height above ground helps to differentiate tree tops. Grounded on an object-based image analysis scheme a detailed mapping of trees in an urbanized environment is processed. Results show high accuracy of tree detection and avoidance of misclassification due to shadows. The study area is the City of Leipzig, Germany. One of the leading German cities, it is home to contiguous community allotments that characterize the configuration of the city. Leipzig has one of the most well-preserved floodplain forests in Europe.

  10. Map of percent scleractinian coral cover and sand along camera tows and ROV tracks of West Maui, Hawaii

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral and sand overlaid on bathymetry and landsat imagery. Optical...

  11. EnviroAtlas - Milwaukee, WI - Tree Cover Along Walkable Roads by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset addresses the tree buffer along heavily traveled roads. The roads are interstates, arterials, and collectors within the EnviroAtlas...

  12. Software development to assist in fault tree construction

    International Nuclear Information System (INIS)

    Simic, Z.; Mikulicic, V.

    1992-01-01

    This paper reviews and classifies fault tree construction methods developed for system safety and reliability. We have outlined two generally different approaches: automatic and interactive fault tree construction. Automatic fault tree approach is no jet enough developed to covering various uses in practice. Interactive approach is intending to be support to the analyst (not vice verse like in automatic approach). The aim is not so high as automatic one but it is accessible. We have favored interactive approach as well because to our opinion the process of fault tree construction is very important for better system understanding. We have described our example of interactive fault tree construction approach. Computer code GIFFT (Graphical Interactive Fault Tree Tool) is in phase of intensive testing and final developing. (author) [hr

  13. Estimating Accuracy of Land-Cover Composition From Two-Stage Clustering Sampling

    Science.gov (United States)

    Land-cover maps are often used to compute land-cover composition (i.e., the proportion or percent of area covered by each class), for each unit in a spatial partition of the region mapped. We derive design-based estimators of mean deviation (MD), mean absolute deviation (MAD), ...

  14. The internal transcribed spacer (ITS region and trnH-psbA [corrected] are suitable candidate loci for DNA barcoding of tropical tree species of India.

    Directory of Open Access Journals (Sweden)

    Abhinandan Mani Tripathi

    Full Text Available DNA barcoding as a tool for species identification has been successful in animals and other organisms, including certain groups of plants. The exploration of this new tool for species identification, particularly in tree species, is very scanty from biodiversity-rich countries like India. rbcL and matK are standard barcode loci while ITS, and trnH-psbA are considered as supplementary loci for plants.Plant barcode loci, namely, rbcL, matK, ITS, trnH-psbA, and the recently proposed ITS2, were tested for their efficacy as barcode loci using 300 accessions of tropical tree species. We tested these loci for PCR, sequencing success, and species discrimination ability using three methods. rbcL was the best locus as far as PCR and sequencing success rate were concerned, but not for the species discrimination ability of tropical tree species. ITS and trnH-psbA were the second best loci in PCR and sequencing success, respectively. The species discrimination ability of ITS ranged from 24.4 percent to 74.3 percent and that of trnH-psbA was 25.6 percent to 67.7 percent, depending upon the data set and the method used. matK provided the least PCR success, followed by ITS2 (59. 0%. Species resolution by ITS2 and rbcL ranged from 9.0 percent to 48.7 percent and 13.2 percent to 43.6 percent, respectively. Further, we observed that the NCBI nucleotide database is poorly represented by the sequences of barcode loci studied here for tree species.Although a conservative approach of a success rate of 60-70 percent by both ITS and trnH-psbA may not be considered as highly successful but would certainly help in large-scale biodiversity inventorization, particularly for tropical tree species, considering the standard success rate of plant DNA barcode program reported so far. The recommended matK and rbcL primers combination may not work in tropical tree species as barcode markers.

  15. Multi-scale remote sensing sagebrush characterization with regression trees over Wyoming, USA: laying a foundation for monitoring

    Science.gov (United States)

    Homer, Collin G.; Aldridge, Cameron L.; Meyer, Debra K.; Schell, Spencer J.

    2012-01-01

    agebrush ecosystems in North America have experienced extensive degradation since European settlement. Further degradation continues from exotic invasive plants, altered fire frequency, intensive grazing practices, oil and gas development, and climate change – adding urgency to the need for ecosystem-wide understanding. Remote sensing is often identified as a key information source to facilitate ecosystem-wide characterization, monitoring, and analysis; however, approaches that characterize sagebrush with sufficient and accurate local detail across large enough areas to support this paradigm are unavailable. We describe the development of a new remote sensing sagebrush characterization approach for the state of Wyoming, U.S.A. This approach integrates 2.4 m QuickBird, 30 m Landsat TM, and 56 m AWiFS imagery into the characterization of four primary continuous field components including percent bare ground, percent herbaceous cover, percent litter, and percent shrub, and four secondary components including percent sagebrush (Artemisia spp.), percent big sagebrush (Artemisia tridentata), percent Wyoming sagebrush (Artemisia tridentata Wyomingensis), and shrub height using a regression tree. According to an independent accuracy assessment, primary component root mean square error (RMSE) values ranged from 4.90 to 10.16 for 2.4 m QuickBird, 6.01 to 15.54 for 30 m Landsat, and 6.97 to 16.14 for 56 m AWiFS. Shrub and herbaceous components outperformed the current data standard called LANDFIRE, with a shrub RMSE value of 6.04 versus 12.64 and a herbaceous component RMSE value of 12.89 versus 14.63. This approach offers new advancements in sagebrush characterization from remote sensing and provides a foundation to quantitatively monitor these components into the future.

  16. Multi-temporal Assessment of Forest Cover, Stocking parameters ...

    African Journals Online (AJOL)

    user

    The study assessed forest cover, stocking parameters and above-ground tree .... deration new emerging ideas on REDD+, this study .... representing areas of change and zero values representing no ..... John Wiley & Sons, Inc. New York.

  17. Homeowner interactions with residential trees in urban areas

    Science.gov (United States)

    Jana Dilley; Kathleen L. Wolf

    2013-01-01

    Urban forests are a critical element in sustainable urban areas because of the many environmental, economic, and social benefits that city trees provide. In order to increase canopy cover in urban areas, residential homeowners, who collectively own the majority of the land in most cities, need to engage in planting and retaining trees on their properties. This...

  18. Assessing tree care professionals' awareness and knowledge about the Asian Longhorned Beetle

    Science.gov (United States)

    Jason M. Hathaway; Cem M. Basman; Susan C. Barro

    2003-01-01

    The level of knowledge and awareness possessed by tree care professionals about the Asian Longhorned Beetle (ALB) is critical for the successful detection and eradication of this pest. A small sample of tree care professionals was surveyed about the ALB (from within the City of Chicago) in the summer of 2001. Results indicate that only 35 percent of survey respondents...

  19. Intramolecular 13C analysis of tree rings provides multiple plant ecophysiology signals covering decades.

    Science.gov (United States)

    Wieloch, Thomas; Ehlers, Ina; Yu, Jun; Frank, David; Grabner, Michael; Gessler, Arthur; Schleucher, Jürgen

    2018-03-22

    Measurements of carbon isotope contents of plant organic matter provide important information in diverse fields such as plant breeding, ecophysiology, biogeochemistry and paleoclimatology. They are currently based on 13 C/ 12 C ratios of specific, whole metabolites, but we show here that intramolecular ratios provide higher resolution information. In the glucose units of tree-ring cellulose of 12 tree species, we detected large differences in 13 C/ 12 C ratios (>10‰) among carbon atoms, which provide isotopically distinct inputs to major global C pools, including wood and soil organic matter. Thus, considering position-specific differences can improve characterisation of soil-to-atmosphere carbon fluxes and soil metabolism. In a Pinus nigra tree-ring archive formed from 1961 to 1995, we found novel 13 C signals, and show that intramolecular analysis enables more comprehensive and precise signal extraction from tree rings, and thus higher resolution reconstruction of plants' responses to climate change. Moreover, we propose an ecophysiological mechanism for the introduction of a 13 C signal, which links an environmental shift to the triggered metabolic shift and its intramolecular 13 C signature. In conclusion, intramolecular 13 C analyses can provide valuable new information about long-term metabolic dynamics for numerous applications.

  20. Permafrost thaw and fire history: implications of boreal tree cover changes on land surface properties and turbulent energy fluxes in the Taiga Plains, Canada

    Science.gov (United States)

    Sonnentag, Oliver; Helbig, Manuel; Payette, Fanny; Wischnewski, Karoline; Kljun, Natascha; Chasmer, Laura; Pappas, Christoforos; Detto, Matteo; Baltzer, Jennifer; Quinton, William; Marsh, Philip

    2016-04-01

    Given their large areal coverage, high carbon densities, and unique land surface properties and disturbance regimes (e.g., wildfires), the world's boreal forests are integral components of the global and regional climate systems. A large portion of boreal forests contain permafrost, i.e., perennially cryotic ground. In the Taiga Plains ecozone in northwestern Canada, the northernmost boreal forests grow on cold (100 m) continuous permafrost (>90 % in areal extent). More southerly boreal forests occur in areas with discontinuous (>50 - 90 % in areal extent), sporadic (>10 - 50 % in areal extent) and isolated permafrost (<10 % in areal extent). Using annual MODIS Percent Tree Cover (PTC) data from the MOD44B product in combination with spatial information on fire history, and permafrost and drainage characteristics, we show that in low-lying, poorly-drained areas along the southern fringe of permafrost, thawing induces widespread decreases in PTC and dominates over PTC increases due to post-fire regrowth. In contrast, PTC appears to be slightly increasing in the central and northern Taiga Plains with more stable discontinuous and continuous permafrost, respectively. While these increases are partly explained by post-fire regrowth, more favourable growing conditions may also contribute to increasing PTC. To better understand the implications of permafrost thaw on land surface properties (e.g., aerodynamic conductance for heat [ga] and surface conductance for water vapour [gs]), and the turbulent fluxes of latent (LE) and sensible heat (H) along the southern fringe of permafrost, we examined nested eddy covariance flux measurements made at two nearby locations at Scotty Creek (61°18' N; 121°18' W) starting May 2013. The low-lying, poorly-drained southern portion of this 152 km2-watershed contains rapidly thawing sporadic permafrost resulting in a highly dynamic mosaic dominated by decreasing forested permafrost peat plateaus, and increasing permafrost-free wetlands

  1. Folding and unfolding phylogenetic trees and networks.

    Science.gov (United States)

    Huber, Katharina T; Moulton, Vincent; Steel, Mike; Wu, Taoyang

    2016-12-01

    Phylogenetic networks are rooted, labelled directed acyclic graphswhich are commonly used to represent reticulate evolution. There is a close relationship between phylogenetic networks and multi-labelled trees (MUL-trees). Indeed, any phylogenetic network N can be "unfolded" to obtain a MUL-tree U(N) and, conversely, a MUL-tree T can in certain circumstances be "folded" to obtain aphylogenetic network F(T) that exhibits T. In this paper, we study properties of the operations U and F in more detail. In particular, we introduce the class of stable networks, phylogenetic networks N for which F(U(N)) is isomorphic to N, characterise such networks, and show that they are related to the well-known class of tree-sibling networks. We also explore how the concept of displaying a tree in a network N can be related to displaying the tree in the MUL-tree U(N). To do this, we develop aphylogenetic analogue of graph fibrations. This allows us to view U(N) as the analogue of the universal cover of a digraph, and to establish a close connection between displaying trees in U(N) and reconciling phylogenetic trees with networks.

  2. Thinning of Tree Stands in the Arctic Zone of Krasnoyarsk Territory With Different Ecological Conditions

    Directory of Open Access Journals (Sweden)

    V. I. Polyakov

    2014-10-01

    Full Text Available In 2001 six permanent sample plots (PSP were established in forest stands differing in degrees of damage by pollution from the Norilsk industrial region. In 2004 the second forest inventory was carried out at these PSP for evaluation of pollutant impacts on stand condition changes. During both inventory procedures the vigor state of every tree was visually categorized according to 6-points scale of «Forest health regulations in Russian Federation». The changeover of tree into fall was also taken into account. Two types of Markov’s models simulating thinning process in tree stands within different ecological conditions has been developed: 1 based on assessment for probability of tree survival during three years; 2 in terms of evaluation of matrix for probability on change of vigor state category in the same period. The reconstruction of tree mortality from 1979 after industrial complex «Nadezda» setting into operation was realized on the basis of probability estimation of dead standing trees conservation during three years observed. The forecast of situation was carried out up to 2030. Using logistic regression the probability of tree survival was established depending on four factors: degree of tree damage by pollutants, tree species, stand location in relief and tree age. The acquired results make it possible to single out an impact of pollutants to tree stands’ resistance from other factors. There was revealed the percent of tree fall, resulted by pollution. The evaluation scale of SO2 gas resistance of tree species was constructed: birch, spruce, larch. Larch showed the highest percent of fall because of pollution.

  3. Modelling the effects of land cover and climate change on soil water partitioning in a boreal headwater catchment

    Science.gov (United States)

    Wang, Hailong; Tetzlaff, Doerthe; Soulsby, Chris

    2018-03-01

    Climate and land cover are two major factors affecting the water fluxes and balance across spatiotemporal scales. These two factors and their impacts on hydrology are often interlinked. The quantification and differentiation of such impacts is important for developing sustainable land and water management strategies. Here, we calibrated the well-known Hydrus-1D model in a data-rich boreal headwater catchment in Scotland to assess the role of two dominant vegetation types (shrubs vs. trees) in regulating the soil water partitioning and balance. We also applied previously established climate projections for the area and replaced shrubs with trees to imitate current land use change proposals in the region, so as to quantify the potential impacts of climate and land cover changes on soil hydrology. Under tree cover, evapotranspiration and deep percolation to recharge groundwater was about 44% and 57% of annual precipitation, whilst they were about 10% lower and 9% higher respectively under shrub cover in this humid, low energy environment. Meanwhile, tree canopies intercepted 39% of annual precipitation in comparison to 23% by shrubs. Soils with shrub cover stored more water than tree cover. Land cover change was shown to have stronger impacts than projected climate change. With a complete replacement of shrubs with trees under future climate projections at this site, evapotranspiration is expected to increase by ∼39% while percolation to decrease by 21% relative to the current level, more pronounced than the modest changes in the two components (seasons, which may result in water stress experienced by the vegetation. The findings provide an important evidence base for adaptive management strategies of future changes in low-energy humid environments, where vegetation growth is usually restricted by radiative energy and not water availability while few studies that quantify soil water partitioning exist.

  4. An Automated Algorithm for Producing Land Cover Information from Landsat Surface Reflectance Data Acquired Between 1984 and Present

    Science.gov (United States)

    Rover, J.; Goldhaber, M. B.; Holen, C.; Dittmeier, R.; Wika, S.; Steinwand, D.; Dahal, D.; Tolk, B.; Quenzer, R.; Nelson, K.; Wylie, B. K.; Coan, M.

    2015-12-01

    Multi-year land cover mapping from remotely sensed data poses challenges. Producing land cover products at spatial and temporal scales required for assessing longer-term trends in land cover change are typically a resource-limited process. A recently developed approach utilizes open source software libraries to automatically generate datasets, decision tree classifications, and data products while requiring minimal user interaction. Users are only required to supply coordinates for an area of interest, land cover from an existing source such as National Land Cover Database and percent slope from a digital terrain model for the same area of interest, two target acquisition year-day windows, and the years of interest between 1984 and present. The algorithm queries the Landsat archive for Landsat data intersecting the area and dates of interest. Cloud-free pixels meeting the user's criteria are mosaicked to create composite images for training the classifiers and applying the classifiers. Stratification of training data is determined by the user and redefined during an iterative process of reviewing classifiers and resulting predictions. The algorithm outputs include yearly land cover raster format data, graphics, and supporting databases for further analysis. Additional analytical tools are also incorporated into the automated land cover system and enable statistical analysis after data are generated. Applications tested include the impact of land cover change and water permanence. For example, land cover conversions in areas where shrubland and grassland were replaced by shale oil pads during hydrofracking of the Bakken Formation were quantified. Analytical analysis of spatial and temporal changes in surface water included identifying wetlands in the Prairie Pothole Region of North Dakota with potential connectivity to ground water, indicating subsurface permeability and geochemistry.

  5. Economic rationale for planting less trees in the face of seedling mortality

    Science.gov (United States)

    Thomas J. Dean; S. Joseph Chang

    2002-01-01

    Simple economic analyses are used to demonstrate that planting extra trees to compensate for initial seedling mortality can actually reduce the profit expected from a pine plantation. At a 6-percent interest rate, the cost of planting 15 or 25 percent additional seedlings compounded to the end of a 30-year rotation exceeds the revenue lost to these rates of seedling...

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

    Science.gov (United States)

    LaMotte, Andrew E.; Wieczorek, Michael

    2010-01-01

    This 30-meter resolution data set represents the tree canopy layer for the conterminous United States for the 2001 time period. The data have been arranged into four tiles to facilitate timely display and manipulation within a Geographic Information System, browse graphic: nlcd01-partition.jpg The National Land Cover Data Set for 2001 was produced through a cooperative project conducted by the Multi-Resolution Land Characteristics (MRLC) Consortium. The MRLC Consortium is a partnership of Federal agencies (www.mrlc.gov), consisting of the U.S. Geological Survey (USGS), the National Oceanic and Atmospheric Administration (NOAA), the U.S. Environmental Protection Agency (USEPA), the U.S. Department of Agriculture (USDA), the U.S. Forest Service (USFS), the National Park Service (NPS), the U.S. Fish and Wildlife Service (USFWS), the Bureau of Land Management (BLM), and the USDA Natural Resources Conservation Service (NRCS). One of the primary goals of the project is to generate a current, consistent, seamless, and accurate National Land Cover Database (NLCD) circa 2001 for the United States at medium spatial resolution. For a detailed definition and discussion on MRLC and the NLCD 2001 products, refer to Homer and others (2004) and http://www.mrlc.gov/mrlc2k.asp. The NLCD 2001 was created by partitioning the United States into mapping-zones. A total of 68 mapping-zones browse graphic: nlcd01-mappingzones.jpg were delineated within the conterminous United States based on ecoregion and geographical characteristics, edge-matching features, and the size requirement of Landsat mosaics. Mapping-zones encompass the whole or parts of several states. Questions about the NLCD mapping zones can be directed to the NLCD 2001 Land Cover Mapping Team at the USGS/EROS, Sioux Falls, SD (605) 594-6151 or mrlc@usgs.gov.

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

    Science.gov (United States)

    LaMotte, Andrew E.; Wieczorek, Michael

    2010-01-01

    This 30-meter resolution data set represents the tree canopy layer for the conterminous United States for the 2001 time period. The data have been arranged into four tiles to facilitate timely display and manipulation within a Geographic Information System, browse graphic: nlcd01-partition.jpg The National Land Cover Data Set for 2001 was produced through a cooperative project conducted by the Multi-Resolution Land Characteristics (MRLC) Consortium. The MRLC Consortium is a partnership of Federal agencies (www.mrlc.gov), consisting of the U.S. Geological Survey (USGS), the National Oceanic and Atmospheric Administration (NOAA), the U.S. Environmental Protection Agency (USEPA), the U.S. Department of Agriculture (USDA), the U.S. Forest Service (USFS), the National Park Service (NPS), the U.S. Fish and Wildlife Service (USFWS), the Bureau of Land Management (BLM), and the USDA Natural Resources Conservation Service (NRCS). One of the primary goals of the project is to generate a current, consistent, seamless, and accurate National Land Cover Database (NLCD) circa 2001 for the United States at medium spatial resolution. For a detailed definition and discussion on MRLC and the NLCD 2001 products, refer to Homer and others (2004) and http://www.mrlc.gov/mrlc2k.asp. The NLCD 2001 was created by partitioning the United States into mapping-zones. A total of 68 mapping-zones browse graphic: nlcd01-mappingzones.jpg were delineated within the conterminous United States based on ecoregion and geographical characteristics, edge-matching features, and the size requirement of Landsat mosaics. Mapping-zones encompass the whole or parts of several states. Questions about the NLCD mapping zones can be directed to the NLCD 2001 Land Cover Mapping Team at the USGS/EROS, Sioux Falls, SD (605) 594-6151 or mrlc@usgs.gov.

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

    Science.gov (United States)

    LaMotte, Andrew E.; Wieczorek, Michael

    2010-01-01

    This 30-meter resolution data set represents the tree canopy layer for the conterminous United States for the 2001 time period. The data have been arranged into four tiles to facilitate timely display and manipulation within a Geographic Information System, browse graphic: nlcd01-partition.jpg. The National Land Cover Data Set for 2001 was produced through a cooperative project conducted by the Multi-Resolution Land Characteristics (MRLC) Consortium. The MRLC Consortium is a partnership of Federal agencies (www.mrlc.gov), consisting of the U.S. Geological Survey (USGS), the National Oceanic and Atmospheric Administration (NOAA), the U.S. Environmental Protection Agency (USEPA), the U.S. Department of Agriculture (USDA), the U.S. Forest Service (USFS), the National Park Service (NPS), the U.S. Fish and Wildlife Service (USFWS), the Bureau of Land Management (BLM), and the USDA Natural Resources Conservation Service (NRCS). One of the primary goals of the project is to generate a current, consistent, seamless, and accurate National Land Cover Database (NLCD) circa 2001 for the United States at medium spatial resolution. For a detailed definition and discussion on MRLC and the NLCD 2001 products, refer to Homer and others (2004) and http://www.mrlc.gov/mrlc2k.asp. The NLCD 2001 was created by partitioning the United States into mapping-zones. A total of 68 mapping-zones browse graphic: nlcd01-mappingzones.jpg were delineated within the conterminous United States based on ecoregion and geographical characteristics, edge-matching features, and the size requirement of Landsat mosaics. Mapping-zones encompass the whole or parts of several states. Questions about the NLCD mapping zones can be directed to the NLCD 2001 Land Cover Mapping Team at the USGS/EROS, Sioux Falls, SD (605) 594-6151 or mrlc@usgs.gov

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

    Science.gov (United States)

    LaMotte, Andrew E.; Wieczorek, Michael

    2010-01-01

    This 30-meter resolution data set represents the tree canopy layer for the conterminous United States for the 2001 time period. The data have been arranged into four tiles to facilitate timely display and manipulation within a Geographic Information System, browse graphic: nlcd01-partition.jpg The National Land Cover Data Set for 2001 was produced through a cooperative project conducted by the Multi-Resolution Land Characteristics (MRLC) Consortium. The MRLC Consortium is a partnership of Federal agencies (www.mrlc.gov), consisting of the U.S. Geological Survey (USGS), the National Oceanic and Atmospheric Administration (NOAA), the U.S. Environmental Protection Agency (USEPA), the U.S. Department of Agriculture (USDA), the U.S. Forest Service (USFS), the National Park Service (NPS), the U.S. Fish and Wildlife Service (USFWS), the Bureau of Land Management (BLM), and the USDA Natural Resources Conservation Service (NRCS). One of the primary goals of the project is to generate a current, consistent, seamless, and accurate National Land Cover Database (NLCD) circa 2001 for the United States at medium spatial resolution. For a detailed definition and discussion on MRLC and the NLCD 2001 products, refer to Homer and others (2004) and http://www.mrlc.gov/mrlc2k.asp. The NLCD 2001 was created by partitioning the United States into mapping-zones. A total of 68 mapping-zones browse graphic: nlcd01-mappingzones.jpg were delineated within the conterminous United States based on ecoregion and geographical characteristics, edge-matching features, and the size requirement of Landsat mosaics. Mapping-zones encompass the whole or parts of several states. Questions about the NLCD mapping zones can be directed to the NLCD 2001 Land Cover Mapping Team at the USGS/EROS, Sioux Falls, SD (605) 594-6151 or mrlc@usgs.gov.

  10. A method for locating potential tree-planting sites in urban areas: a case study of Los Angeles, USA

    Science.gov (United States)

    Chunxia Wua; Qingfu Xiaoa; Gregory E. McPherson

    2008-01-01

    A GIS-based method for locating potential tree-planting sites based on land cover data is introduced. Criteria were developed to identify locations that are spatially available for potential tree planting based on land cover, sufficient distance from impervious surfaces, a minimum amount of pervious surface, and no crown overlap with other trees. In an ArcGIS...

  11. Reconciliation of Gene and Species Trees

    Directory of Open Access Journals (Sweden)

    L. Y. Rusin

    2014-01-01

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

  12. 49 CFR 179.100-12 - Manway nozzle, cover and protective housing.

    Science.gov (United States)

    2010-10-01

    ... listed in § 179.101. Manway cover shall be attached to manway nozzle by through or stud bolts not... twenty 3/4-inch studs. The shearing value of the bolts attaching protective housing to manway cover must not exceed 70 percent of the shearing value of bolts attaching manway cover to manway nozzle. Housing...

  13. Impact of urban environmental pollution on growth, leaf damage, and chemical constituents of Warsaw urban trees

    Science.gov (United States)

    Waldemar Chmielewski; Wojciech Dmuchowski; Stanislaw Suplat

    1998-01-01

    In the last 10 years, 3.5 percent of the tree population died annually in PolandÕs largest and most polluted cities, which is a problem of economic importance. Dieback of streetside trees in Warsaw is a long term process. It is an effect of biological reactions of trees to unfavorable conditions in the urban environment, particularly air and soil pollution and water...

  14. Land cover in the Guayas Basin using SAR images from low resolution ASAR Global mode to high resolution Sentinel-1 images

    Science.gov (United States)

    Bourrel, Luc; Brodu, Nicolas; Frappart, Frédéric

    2016-04-01

    Remotely sensed images allow a frequent monitoring of land cover variations at regional and global scale. Recently launched Sentinel-1 satellite offers a global cover of land areas at an unprecedented spatial (20 m) and temporal (6 days at the Equator). We propose here to compare the performances of commonly used supervised classification techniques (i.e., k-nearest neighbors, linear and Gaussian support vector machines, naive Bayes, linear and quadratic discriminant analyzes, adaptative boosting, loggit regression, ridge regression with one-vs-one voting, random forest, extremely randomized trees) for land cover applications in the Guayas Basin, the largest river basin of the Pacific coast of Ecuator (area ~32,000 km²). The reason of this choice is the importance of this region in Ecuatorian economy as its watershed represents 13% of the total area of Ecuador where 40% of the Ecuadorian population lives. It also corresponds to the most productive region of Ecuador for agriculture and aquaculture. Fifty percents of the country shrimp farming production comes from this watershed, and represents with agriculture the largest source of revenue of the country. Similar comparisons are also performed using ENVISAT ASAR images acquired in global mode (1 km of spatial resolution). Accuracy of the results will be achieved using land cover map derived from multi-spectral images.

  15. The contribution of trees outside forests to national tree biomass and carbon stocks--a comparative study across three continents.

    Science.gov (United States)

    Schnell, Sebastian; Altrell, Dan; Ståhl, Göran; Kleinn, Christoph

    2015-01-01

    In contrast to forest trees, trees outside forests (TOF) often are not included in the national monitoring of tree resources. Consequently, data about this particular resource is rare, and available information is typically fragmented across the different institutions and stakeholders that deal with one or more of the various TOF types. Thus, even if information is available, it is difficult to aggregate data into overall national statistics. However, the National Forest Monitoring and Assessment (NFMA) programme of FAO offers a unique possibility to study TOF resources because TOF are integrated by default into the NFMA inventory design. We have analysed NFMA data from 11 countries across three continents. For six countries, we found that more than 10% of the national above-ground tree biomass was actually accumulated outside forests. The highest value (73%) was observed for Bangladesh (total forest cover 8.1%, average biomass per hectare in forest 33.4 t ha(-1)) and the lowest (3%) was observed for Zambia (total forest cover 63.9%, average biomass per hectare in forest 32 t ha(-1)). Average TOF biomass stocks were estimated to be smaller than 10 t ha(-1). However, given the large extent of non-forest areas, these stocks sum up to considerable quantities in many countries. There are good reasons to overcome sectoral boundaries and to extend national forest monitoring programmes on a more systematic basis that includes TOF. Such an approach, for example, would generate a more complete picture of the national tree biomass. In the context of climate change mitigation and adaptation, international climate mitigation programmes (e.g. Clean Development Mechanism and Reduced Emission from Deforestation and Degradation) focus on forest trees without considering the impact of TOF, a consideration this study finds crucial if accurate measurements of national tree biomass and carbon pools are required.

  16. Percent Coverage

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Percent Coverage is a spreadsheet that keeps track of and compares the number of vessels that have departed with and without observers to the numbers of vessels...

  17. 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.

  18. Beyond Tree Throw: Wind, Water, Rock and the Mechanics of Tree-Driven Bedrock Physical Weathering

    Science.gov (United States)

    Marshall, J. A.; Anderson, R. S.; Dawson, T. E.; Dietrich, W. E.; Minear, J. T.

    2017-12-01

    Tree throw is often invoked as the dominant process in converting bedrock to soil and thus helping to build the Critical Zone (CZ). In addition, observations of tree roots lifting sidewalk slabs, occupying cracks, and prying slabs of rock from cliff faces have led to a general belief in the power of plant growth forces. These common observations have led to conceptual models with trees at the center of the soil genesis process. This is despite the observation that tree throw is rare in many forested settings, and a dearth of field measurements that quantify the magnitude of growth forces. While few trees blow down, every tree grows roots, inserting many tens of percent of its mass below ground. Yet we lack data quantifying the role of trees in both damaging bedrock and detaching it (and thus producing soil). By combing force measurements at the tree-bedrock interface with precipitation, solar radiation, wind speed, and wind-driven tree sway data we quantified the magnitude and frequency of tree-driven soil-production mechanisms from two contrasting climatic and lithologic regimes (Boulder and Eel Creek CZ Observatories). Preliminary data suggests that in settings with relatively thin soils, trees can damage and detach rock due to diurnal fluctuations, wind response and rainfall events. Surprisingly, our data suggests that forces from roots and trunks growing against bedrock are insufficient to pry rock apart or damage bedrock although much more work is needed in this area. The frequency, magnitude and style of wind-driven tree forces at the bedrock interface varies considerably from one to another species. This suggests that tree properties such as mass, elasticity, stiffness and branch structure determine whether trees respond to gusts big or small, move at the same frequency as large wind gusts, or are able to self-dampen near-ground sway response to extended wind forces. Our measurements of precipitation-driven and daily fluctuations in root pressures exerted on

  19. INDIGENOUS COMMUNITY TREE INVENTORY: ASSESSMENT OF DATA QUALITY

    Directory of Open Access Journals (Sweden)

    M. F. Fauzi

    2016-09-01

    Full Text Available The citizen science program to supplement authoritative data in tree inventory has been well implemented in various countries. However, there is a lack of study that assesses correctness and accuracy of tree data supplied by citizens. This paper addresses the issue of tree data quality supplied by semi-literate indigenous group. The aim of this paper is to assess the correctness of attributes (tree species name, height and diameter at breast height and the accuracy of tree horizontal positioning data supplied by indigenous people. The accuracy of the tree horizontal position recorded by GNSS-enable smart phone was found to have a RMSE value of ± 8m which is not suitable to accurately locate individual tree position in tropical rainforest such as the Royal Belum State Park. Consequently, the tree species names contributed by indigenous people were only 20 to 30 percent correct as compared with the reference data. However, the combination of indigenous respondents comprising of different ages, experience and knowledge working in a group influence less attribute error in data entry and increase the use of free text rather than audio methods. The indigenous community has a big potential to engage with scientific study due to their local knowledge with the research area, however intensive training must be given to empower their skills and several challenges need to be addressed.

  20. Dwarf mistletoe and host tree interactions in managed forests of the Pacific Northwest.

    Science.gov (United States)

    Donald M. Knutson; Robert. Tinnin

    1980-01-01

    Dwarf mistletoes in the Pacific Northwest infect true firs, larch, pine, Douglas-fir, and hemlock. Forty-one percent of all stands east of the crest of the Cascade Range and 10 percent of west-side stands are infected. General characteristics of dwarf mistletoe are discussed including mortality and growth losses rate of spread within a tree and within stands. Relation...

  1. Modeling and Testing Landslide Hazard Using Decision Tree

    Directory of Open Access Journals (Sweden)

    Mutasem Sh. Alkhasawneh

    2014-01-01

    Full Text Available This paper proposes a decision tree model for specifying the importance of 21 factors causing the landslides in a wide area of Penang Island, Malaysia. These factors are vegetation cover, distance from the fault line, slope angle, cross curvature, slope aspect, distance from road, geology, diagonal length, longitude curvature, rugosity, plan curvature, elevation, rain perception, soil texture, surface area, distance from drainage, roughness, land cover, general curvature, tangent curvature, and profile curvature. Decision tree models are used for prediction, classification, and factors importance and are usually represented by an easy to interpret tree like structure. Four models were created using Chi-square Automatic Interaction Detector (CHAID, Exhaustive CHAID, Classification and Regression Tree (CRT, and Quick-Unbiased-Efficient Statistical Tree (QUEST. Twenty-one factors were extracted using digital elevation models (DEMs and then used as input variables for the models. A data set of 137570 samples was selected for each variable in the analysis, where 68786 samples represent landslides and 68786 samples represent no landslides. 10-fold cross-validation was employed for testing the models. The highest accuracy was achieved using Exhaustive CHAID (82.0% compared to CHAID (81.9%, CRT (75.6%, and QUEST (74.0% model. Across the four models, five factors were identified as most important factors which are slope angle, distance from drainage, surface area, slope aspect, and cross curvature.

  2. Land Cover Classification from Multispectral Data Using Computational Intelligence Tools: A Comparative Study

    Directory of Open Access Journals (Sweden)

    André Mora

    2017-11-01

    Full Text Available This article discusses how computational intelligence techniques are applied to fuse spectral images into a higher level image of land cover distribution for remote sensing, specifically for satellite image classification. We compare a fuzzy-inference method with two other computational intelligence methods, decision trees and neural networks, using a case study of land cover classification from satellite images. Further, an unsupervised approach based on k-means clustering has been also taken into consideration for comparison. The fuzzy-inference method includes training the classifier with a fuzzy-fusion technique and then performing land cover classification using reinforcement aggregation operators. To assess the robustness of the four methods, a comparative study including three years of land cover maps for the district of Mandimba, Niassa province, Mozambique, was undertaken. Our results show that the fuzzy-fusion method performs similarly to decision trees, achieving reliable classifications; neural networks suffer from overfitting; while k-means clustering constitutes a promising technique to identify land cover types from unknown areas.

  3. Constraints and opportunities for tree diversity management along the forest transition curve to achieve multifunctional agriculture

    NARCIS (Netherlands)

    Ordonez, J.C.; Luedeling, E.; Kindt, R.; Tata, H.L.; Harja, D.; Jamnadass, R.; Noordwijk, van M.

    2014-01-01

    On-farm tree diversity patterns result from a social-ecological process shaped by different actors. Farmer preferences, tree-site matching, seed dispersal, tree domestication and delivery via nurseries all play important roles in forming these patterns. As part of a wider interest in tree cover

  4. 7 CFR 457.106 - Texas citrus tree crop insurance provisions.

    Science.gov (United States)

    2010-01-01

    ... proper times. Root stock—A root or a piece of a root of one tree variety onto which a bud from another... will be increased by 46 percent as a result of the additional six months of coverage for that crop year...

  5. Recognizing human actions by learning and matching shape-motion prototype trees.

    Science.gov (United States)

    Jiang, Zhuolin; Lin, Zhe; Davis, Larry S

    2012-03-01

    A shape-motion prototype-based approach is introduced for action recognition. The approach represents an action as a sequence of prototypes for efficient and flexible action matching in long video sequences. During training, an action prototype tree is learned in a joint shape and motion space via hierarchical K-means clustering and each training sequence is represented as a labeled prototype sequence; then a look-up table of prototype-to-prototype distances is generated. During testing, based on a joint probability model of the actor location and action prototype, the actor is tracked while a frame-to-prototype correspondence is established by maximizing the joint probability, which is efficiently performed by searching the learned prototype tree; then actions are recognized using dynamic prototype sequence matching. Distance measures used for sequence matching are rapidly obtained by look-up table indexing, which is an order of magnitude faster than brute-force computation of frame-to-frame distances. Our approach enables robust action matching in challenging situations (such as moving cameras, dynamic backgrounds) and allows automatic alignment of action sequences. Experimental results demonstrate that our approach achieves recognition rates of 92.86 percent on a large gesture data set (with dynamic backgrounds), 100 percent on the Weizmann action data set, 95.77 percent on the KTH action data set, 88 percent on the UCF sports data set, and 87.27 percent on the CMU action data set.

  6. Tree growth and vegetation activity at the ecosystem-scale in the eastern Mediterranean

    Science.gov (United States)

    Coulthard, Bethany L.; Touchan, Ramzi; Anchukaitis, Kevin J.; Meko, David M.; Sivrikaya, Fatih

    2017-08-01

    Linking annual tree growth with remotely-sensed terrestrial vegetation indices provides a basis for using tree rings as proxies for ecosystem primary productivity over large spatial and long temporal scales. In contrast with most previous tree ring/remote sensing studies that have focused on temperature-limited boreal and taiga environments, here we compare the normalized difference vegetation index (NDVI) with a network of Pinus brutia tree ring width chronologies collected along ecological gradients in semiarid Cyprus, where both radial tree growth and broader vegetation activity are controlled by drought. We find that the interaction between precipitation, elevation, and land-cover type generate a relationship between radial tree growth and NDVI. While tree ring chronologies at higher-elevation forested sites do not exhibit climate-driven linkages with NDVI, chronologies at lower-elevation dry sites are strongly correlated with NDVI during the winter precipitation season. At lower-elevation sites, land cover is dominated by grasslands and shrublands and tree ring widths operate as a proxy for ecosystem-scale vegetation activity. Tree rings can therefore be used to reconstruct productivity in water-limited grasslands and shrublands, where future drought stress is expected to alter the global carbon cycle, biodiversity, and ecosystem functioning in the 21st century.

  7. Three-dimensional object recognition using similar triangles and decision trees

    Science.gov (United States)

    Spirkovska, Lilly

    1993-01-01

    A system, TRIDEC, that is capable of distinguishing between a set of objects despite changes in the objects' positions in the input field, their size, or their rotational orientation in 3D space is described. TRIDEC combines very simple yet effective features with the classification capabilities of inductive decision tree methods. The feature vector is a list of all similar triangles defined by connecting all combinations of three pixels in a coarse coded 127 x 127 pixel input field. The classification is accomplished by building a decision tree using the information provided from a limited number of translated, scaled, and rotated samples. Simulation results are presented which show that TRIDEC achieves 94 percent recognition accuracy in the 2D invariant object recognition domain and 98 percent recognition accuracy in the 3D invariant object recognition domain after training on only a small sample of transformed views of the objects.

  8. Ponderosa pine seed-tree removal reduces stocking only slightly

    Science.gov (United States)

    Philip M. McDonald

    1969-01-01

    After ponderosa pine seed trees were removed on the Challenge Experimental Forest, California, seedling stocking fell by 3.8 percent or about 212 seedlings per acre. This loss is slightly less than that incurred from natural mortality, and one that did not reduce regeneration levels below the minimum standard.

  9. Assessing urban forest effects and values, Los Angeles' urban forest

    Science.gov (United States)

    David J. Nowak; Robert E. III Hoehn; Daniel E. Crane; Lorraine Weller; Antonio. Davila

    2011-01-01

    An analysis of trees in Los Angeles, CA, reveals that this area has about 6 million trees with tree and shrub canopies that cover 24.9 percent of the city. The most common tree species are Italian cypress, scrub oak, laurel sumac, Mexican fan palm, and Indian laurel, Trees in Los Angeles currently store about 1.3 million tons of carbon (4.7 million tons CO2...

  10. Assessing urban forest effects and values: Douglas County, Kansas

    Science.gov (United States)

    David J. Nowak; Allison R. Bodine; Robert E. Hoehn; Alexis Ellis; Kim Bomberger; Daniel E. Crane; Theodore A. Endreny; Thomas Taggert; Emily. Stephan

    2014-01-01

    An analysis of trees in Douglas County, Kansas, reveals that this area has about 14,164,000 trees with tree and shrub canopy that covers 25.2 percent of the county. The most common tree species are American elm, northern hackberry, eastern redcedar, Osage-orange, and honeylocust. Trees in Douglas County currently store about 1.7 million tons of carbon (6.4 million tons...

  11. Houston’s Urban Forest, 2015

    Science.gov (United States)

    David J. Nowak; Allison R. Bodine; Robert E. Hoehn; Christopher B. Edgar; Gretchen Riley; Dudley R. Hartel; Kerry J. Dooley; Sharon M. Stanton; Mark A. Hatfield; Thomas J. Brandeis; Tonya W. Lister

    2017-01-01

    An analysis of the urban forest in Houston, Texas, reveals that this area has an estimated 33.3 million live trees with tree canopy that covers 18.4 percent of the city. Roughly 19.2 million of the city’s trees are located on private lands. The most common tree species are yaupon, Chinese tallowtree, Chinese privet, Japanese privet, and sugarberry. Trees in Houston...

  12. Using Unmanned Aerial Vehicles to Assess Vegetative Cover in Sagebrush Steppe Ecosytstems

    Energy Technology Data Exchange (ETDEWEB)

    Robert P. Breckenridge

    2005-09-01

    The Idaho National Laboratory (INL), in conjunction with the University of Idaho, is evaluating novel approaches for using unmanned aerial vehicles (UAVs) as a quicker and safer method for monitoring biotic resources. Evaluating vegetative cover is an important factor in understanding the sustainability of many ecosystems. In assessing vegetative cover, methods that improve accuracy and cost efficiency could revolutionize how biotic resources are monitored on western federal lands. Sagebrush steppe ecosystems provide important habitat for a variety of species, some of which are important indicator species (e.g., sage grouse). Improved methods are needed to support monitoring these habitats because there are not enough resource specialists or funds available for comprehensive ground evaluation of these ecosystems. In this project, two types of UAV platforms (fixed wing and helicopter) were used to collect still-frame imagery to assess cover in sagebrush steppe ecosystems. This paper discusses the process for collecting and analyzing imagery from the UAVs to (1) estimate total percent cover, (2) estimate percent cover for six different types of vegetation, and (3) locate sage grouse based on representative decoys. The field plots were located on the INL site west of Idaho Falls, Idaho, in areas with varying amounts and types of vegetative cover. A software program called SamplePoint developed by the U.S. Department of Agriculture, Agricultural Research Service (USDA-ARS) was used to evaluate the imagery for percent cover for the six vegetation types (bare ground, litter, shrubs, dead shrubs, grasses, and forbs). Results were compared against standard field measurements to assess accuracy.

  13. Killing Unwanted West Indies Mahogany Trees by Peeling and Frilling

    Science.gov (United States)

    R. W. Nobles; C. B. Briscoe

    1966-01-01

    Peeling and frilling each killed approximately 70 percent of treated West Indies mahogany, but peeling killed a higher percentage of trees between 18 and 33 centimeters (7 and 13 inches) than did frilling. Essentially all mortality occurred within the first 15 months following treatment.

  14. Completion of the National Land Cover Database (NLCD) 1992–2001 Land Cover Change Retrofit product

    Science.gov (United States)

    Fry, J.A.; Coan, Michael; Homer, Collin G.; Meyer, Debra K.; Wickham, J.D.

    2009-01-01

    The Multi-Resolution Land Characteristics Consortium has supported the development of two national digital land cover products: the National Land Cover Dataset (NLCD) 1992 and National Land Cover Database (NLCD) 2001. Substantial differences in imagery, legends, and methods between these two land cover products must be overcome in order to support direct comparison. The NLCD 1992-2001 Land Cover Change Retrofit product was developed to provide more accurate and useful land cover change data than would be possible by direct comparison of NLCD 1992 and NLCD 2001. For the change analysis method to be both national in scale and timely, implementation required production across many Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) path/rows simultaneously. To meet these requirements, a hybrid change analysis process was developed to incorporate both post-classification comparison and specialized ratio differencing change analysis techniques. At a resolution of 30 meters, the completed NLCD 1992-2001 Land Cover Change Retrofit product contains unchanged pixels from the NLCD 2001 land cover dataset that have been cross-walked to a modified Anderson Level I class code, and changed pixels labeled with a 'from-to' class code. Analysis of the results for the conterminous United States indicated that about 3 percent of the land cover dataset changed between 1992 and 2001.

  15. Canopy cover negatively affects arboreal ant species richness in a tropical open habitat

    Directory of Open Access Journals (Sweden)

    A. C. M. Queiroz

    Full Text Available Abstract We tested the hypothesis of a negative relationship between vegetation characteristics and ant species richness in a Brazilian open vegetation habitat, called candeial. We set up arboreal pitfalls to sample arboreal ants and measured the following environmental variables, which were used as surrogate of environmental heterogeneity: tree richness, tree density, tree height, circumference at the base of the plants, and canopy cover. Only canopy cover had a negative effect on the arboreal ant species richness. Vegetation characteristics and plant species composition are probably homogeneous in candeial, which explains the lack of relationship between other environmental variables and ant richness. Open vegetation habitats harbor a large number of opportunistic and generalist species, besides specialist ants from habitats with high temperatures. An increase in canopy cover decreases sunlight incidence and may cause local microclimatic differences, which negatively affect the species richness of specialist ants from open areas. Canopy cover regulates the richness of arboreal ants in open areas, since only few ant species are able to colonize sites with dense vegetation; most species are present in sites with high temperature and luminosity. Within open vegetation habitats the relationship between vegetation characteristics and species richness seems to be the opposite from closed vegetation areas, like forests.

  16. Tree canopy types constrain plant distributions in ponderosa pine-Gambel oak forests, northern Arizona

    Science.gov (United States)

    Scott R. Abella

    2009-01-01

    Trees in many forests affect the soils and plants below their canopies. In current high-density southwestern ponderosa pine (Pinus ponderosa) forests, managers have opportunities to enhance multiple ecosystem values by manipulating tree density, distribution, and canopy cover through tree thinning. I performed a study in northern Arizona ponderosa...

  17. The urban forests of Philadelphia

    Science.gov (United States)

    David J. Nowak; Allison R. Bodine; Robert Hoehn; Alexis Ellis; Sarah C. Low; Lara A. Roman; Jason G. Henning; Emily Stephan; Tom Taggert; Ted. Endreny

    2016-01-01

    An analysis of the urban forest in Philadelphia, Pennsylvania, reveals that this city has an estimated 2.9 million trees (encompassing all woody plants greater than 1 inch diameter at breast height [d.b.h]) with tree canopy that covers 20 percent of the city. The most common tree species are spicebush, black cherry, ash, tree-of-heaven, and boxelder, but the most...

  18. EnviroAtlas - Cleveland, OH - 51m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is vegetated. In this community, vegetated cover is defined as Trees & Forest,...

  19. The influence of tree thinning on the establishment of herbaceous ...

    African Journals Online (AJOL)

    The influence of tree thinning on the establishment of herbaceous plants in a semi-arid savanna of southern Africa. GN Smit, FG Rethman. Abstract. The investigation was conducted on an area covered by a dense stand of Colophospermum mopane. Seven plots (65 m × 180 m) were subjected to different intensities of tree ...

  20. Assessing the ecosystem service of air pollutant removal by urban trees in Guangzhou (China).

    Science.gov (United States)

    Jim, C Y; Chen, Wendy Y

    2008-09-01

    In Chinese cities, air pollution has become a serious and aggravating environmental problem undermining the sustainability of urban ecosystems and the quality of urban life. Besides technical solutions to abate air pollution, urban vegetation is increasingly recognized as an alternative ameliorative method by removing some pollutants mainly through dry deposition process. This paper assesses the capability and monetary value of this ecosystem service in Guangzhou city in South China. The results indicated an annual removal of SO(2), NO(2) and total suspended particulates at about 312.03 Mg, and the benefits were valued at RMB90.19 thousand (US$1.00=RMB8.26). More removal was realized by recreational land use due to a higher tree cover. Higher concentration of pollutants in the dry winter months induced more removal. The lower cost of pollution abatement in China generated a relatively subdued monetary value of this environmental benefit in comparison with developed countries. Younger districts with more extensive urban trees stripped more pollutants from the air, and this capacity was anticipated to increase further as their trees gradually reach final dimensions and establish a greater tree cover. Tree cover and pollutant concentration constitute the main factors in pollutant removal by urban trees. The efficiency of atmospheric cleansing by trees in congested Chinese cities could be improved by planting more trees other than shrubs or grass, diversifying species composition and biomass structure, and providing sound green space management. The implications for greenery design were discussed with a view to maximizing this ecosystem service in Chinese cities and other developing metropolises.

  1. Estimating tree species diversity in the savannah using NDVI and woody canopy cover

    CSIR Research Space (South Africa)

    Madonsela, Sabelo

    2018-04-01

    Full Text Available Remote sensing applications in biodiversity research often rely on the establishment of relationships between spectral information from the image and tree species diversity measured in the field. Most studies have used normalized difference...

  2. Urban tree effects on soil organic carbon.

    Directory of Open Access Journals (Sweden)

    Jill L Edmondson

    Full Text Available Urban trees sequester carbon into biomass and provide many ecosystem service benefits aboveground leading to worldwide tree planting schemes. Since soils hold ∼75% of ecosystem organic carbon, understanding the effect of urban trees on soil organic carbon (SOC and soil properties that underpin belowground ecosystem services is vital. We use an observational study to investigate effects of three important tree genera and mixed-species woodlands on soil properties (to 1 m depth compared to adjacent urban grasslands. Aboveground biomass and belowground ecosystem service provision by urban trees are found not to be directly coupled. Indeed, SOC enhancement relative to urban grasslands is genus-specific being highest under Fraxinus excelsior and Acer spp., but similar to grasslands under Quercus robur and mixed woodland. Tree cover type does not influence soil bulk density or C∶N ratio, properties which indicate the ability of soils to provide regulating ecosystem services such as nutrient cycling and flood mitigation. The trends observed in this study suggest that genus selection is important to maximise long-term SOC storage under urban trees, but emerging threats from genus-specific pathogens must also be considered.

  3. Colour atlas on forest disease. Diagnosis of tree diseases. Farbatlas Waldschaeden. Diagnose von Baumkrankheiten

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann, G.; Winter, K.; Nienhaus, F.; Butin, H.

    1988-01-01

    The 'Colour Atlas on Forest Disease' facilitates the diagnosis of syndromes due to different causes in 16 genera or species of forest trees. It contains a selection of more than 200 important, frequent, or conspicuous disease phenomena. These include: in a ratio of 8 percent partly novel, complex diseases due to causes not entirely elucidated, 35 percent known forms of damage of abiotic origin (extreme weather conditions, nutrient deficiency, classical damage due to environmental pollution and de-icing salt, damage through herbicides), and 57 percent diseases and harm of biotic origin (fungal infections, infestation with insect pest, bacterial, mycoplasmal, rickettsia-type and viral diseases, other damage). 418 colour photographs show characteristic features of tree diseases and provide clues to causes and possible alternative diseases liable to be mixed up with the actual one. The selection decided on is restricted to symptoms visible externally in the area of the crowns as far as they are distinguishable in the field. (orig./MG) With 418 colour photographs.

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

    Science.gov (United States)

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

    2017-04-01

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

  5. Map of percent scleractinian coral cover along camera tows and ROV tracks in the Auau Channel, Island of Maui, Hawaii

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This map displays optical validation observation locations and percent coverage of scleractinian coral overlaid on bathymetry and landsat imagery. Optical data were...

  6. Radial growth and percent of latewood in Scots pine provenance trials in Western and Central Siberia

    Directory of Open Access Journals (Sweden)

    S. R. Kuzmin

    2016-12-01

    Full Text Available Percent of latewood of Boguchany and Suzun Scots pine climatypes has been studied in two provenance trials (place of origin and trial place. For Boguchany climatype the place of origin is south taiga of Central Siberia (Krasnoyarsk Krai, the place of trial is forest-steppe zone of Western Siberia (Novosibirsk Oblast and vice versa for Suzun climatype – forest-steppe zone of Western Siberia is the place of origin, south taiga is the place of trial. Comparison of annual average values of latewood percent of Boguchany climatype in south taiga and forest-steppe revealed the same numbers – 19 %. Annual variability of this trait in south taiga is distinctly lower and equal to 17 %, in forest-steppe – 35 %. Average annual values of latewood percent of Suzun climatype in the place of origin and trial place are close (20 and 21 %. Variability of this trait for Suzun climatype is higher than for Boguchany and equal to 23 % in south taiga and 42 % in forest-steppe. Climatic conditions in southern taiga in Central Siberia in comparison with forest-steppe in Western Siberia make differences between climatypes stronger. Differences between climatypes are expressed in different age of maximal increments of diameter, different tree ring width and latewood percent values and in different latewood reaction to weather conditions.

  7. Indirect effects of land-use legacies determine tree colonization patterns in abandoned heathland

    DEFF Research Database (Denmark)

    Kepfer Rojas, Sebastian; Verheyen, Kris; Johannsen, Vivian Kvist

    2015-01-01

    of tree/shrubs in the heathland. Further, we used high-resolution LiDAR data to classify the vegetation and identify forest patches. In the analysis, we first used a logistic mixed model to test whether colonization of tree and shrub species differed between areas with different land-use history......Questions How do land-use legacies and distance to forest patches influence tree colonization at a post-agricultural heathland? Are colonizing species with different life-history traits affected differently by these factors? Is the effect of increased nutrient availability from land-use legacies...... and whether it was influenced by the distance to forest patches and life-history traits (seed mass) of colonizing species. Then, to determine how different factors influence colonization, we explored the direct and indirect relationships among nutrient availability, density of adult trees, canopy cover, cover...

  8. Evapotranspiration from a Mediterranean evergreen oak savannah: The role of trees and pasture

    Science.gov (United States)

    Paço, Teresa A.; David, Teresa S.; Henriques, Manuel O.; Pereira, João S.; Valente, Fernanda; Banza, João; Pereira, Fernando L.; Pinto, Clara; David, Jorge S.

    2009-05-01

    SummaryMediterranean evergreen oak woodlands of southern Portugal ( montados) are savannah-type ecosystems with a widely sparse tree cover, over extensive grassland. Therefore, ecosystem water fluxes derive from two quite differentiated sources: the trees and the pasture. Partitioning of fluxes according to these different sources is necessary to quantify overall ecosystem water losses as well as to improve knowledge on its functional behaviour. In southern Iberia, these woodlands are subjected to recurrent droughts. Therefore, reaction/resilience to water stress becomes an essential feature of vegetation on these ecosystems. Long-term tree transpiration was recorded for 6 years from a sample of holm oak ( Quercus ilex ssp. rotundifolia) trees, using the Granier sap flow method. Ecosystem transpiration was measured by the eddy covariance technique for an 11-month period (February to December 2005), partly coincident with a drought year. Pasture transpiration was estimated as the difference between ecosystem (eddy covariance) and tree (sap flow) transpiration. Pasture transpiration stopped during the summer, when the surface soil dried up. In the other seasons, pasture transpiration showed a strong dependence on rainfall occurrence and on top soil water. Conversely, trees were able to maintain transpiration throughout the summer due to the deep root access to groundwater. Q. ilex trees showed a high resilience to both seasonal and annual drought. Tree transpiration represented more than half of ecosystem transpiration, in spite of the low tree density (30 trees ha -1) and crown cover fraction (21%). Tree evapotranspiration was dominated by transpiration (76%), and interception loss represented only 24% of overall tree evaporation.

  9. Multielemental analyses of tree rings by inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Hall, G.S.

    1990-01-01

    Inductively coupled plasma mass spectrometry (ICP-MS) was evaluated for major, minor, trace, and ultra-trace elemental analyses of individual tree rings. The samples were obtained from an old-growth Douglas fir growing near Mount St. Helens volcano, and from trees at various other North American sites. Eightly percent of elements from Li to U had detection limits in the solid (wood) below 8.0 ng g -1 . Two anomalous peaks occur in Mount St. Helens samples at A.D. 1478 and 1490 that closely correlate with past eruptions of the volcano. These results show that ICP-MS is a rapid and sensitive analytical method for multielemental analyses of individual tree rings. (author) 16 refs.; 2 figs.; 2 tabs

  10. Effects of soil surface management practices on soil and tree ...

    African Journals Online (AJOL)

    Effects on soil, leaf and fruit element concentrations of organic (compost, straw mulch and hand weeding) and integrated (inorganic fertilisers and herbicide usage; IP) soil surface management practices in the tree rows, in combination with weed covers, cover crops and straw mulch in the work rows, were investigated in a ...

  11. Assessing urban forest effects and values: Toronto's urban forest

    Science.gov (United States)

    David J. Nowak; Robert E. III Hoehn; Allison R. Bodine; Eric J. Greenfield; Alexis Ellis; Theodore A. Endreny; Yang Yang; Tian Zhou; Ruthanne. Henry

    2013-01-01

    An analysis of trees in Toronto, Ontario, reveals that this city has about 10.2 million trees with a tree and shrub canopy that covers approximately 26.6 percent of the city. The most common tree species are eastern white-cedar, sugar maple, and Norway maple. The urban forest currently stores an estimated 1.1 million metric tons of carbon valued at CAD$25.0 million. In...

  12. Austin's Urban Forest, 2014

    Science.gov (United States)

    David J. Nowak; Allison R. Bodine; Robert E. Hoehn; Christopher B. Edgar; Dudley R. Hartel; Tonya W. Lister; Thomas J. Brandeis

    2016-01-01

    An analysis of the urban forest in Austin, Texas, reveals that this area has an estimated 33.8 million trees with tree canopy that covers 30.8 percent of the city. The most common tree species are Ashe juniper, cedar elm, live oak, sugarberry, and Texas persimmon. Trees in Austin currently store about 1.9 million tons of carbon (7.0 million tons of carbon dioxide [CO...

  13. The Relationship between On-Farm Shade Trees and Cocoa Yields in Ghana

    DEFF Research Database (Denmark)

    Asare, Richard

    Cocoa (Theobroma cacao L.) is a crop that is widely cultivated across West Africa with Côte d’Ivoire, Cameroon, Ghana and Nigeria contributing about 70% of the global production. In Ghana cocoa contributes significantly to the national economy as over 20% of the world’s cocoa production comes from...... the country, making it the world’s second largest producer with an annual production level of over 700,000 metric tons, and an estimated cultivation area of ca. 1.6 million ha. Cocoa is mostly cultivated by smallholder farmers either as a monocrop or in association with other food crops, tree crops and under...... the cover of shade trees – cocoa agroforestry. This thesis hypothesizes that canopy cover of shade trees in low input (low-to-no fertilizer application) cocoa growing systems can contribute to cocoa yield improvements. The main theme deals with shade trees diversity and its effects on cocoa production...

  14. Apple Trees - A Source of Energy

    International Nuclear Information System (INIS)

    Kricka, T.; Pliestic, S.

    1997-01-01

    There is a large quantity of leftover (cut-off) branches after the trimming of fruit trees, both during in winter or during the vegetation period. In intensive production, trimming most often occurs as a combined cut, which means it is done both manually and with the help of machines. The leftover mass has to be taken care of in both cases. This paper deals with the apple tree biomass in the last 10 years expressed in tons, covering both the winter and vegetation period, and also about the possibility of using this biomass to replace fossil fuels. (author)

  15. Specification for corrosion-resisting chromium and chromium-nickel steel covered welding electrodes

    International Nuclear Information System (INIS)

    Anon.

    1983-01-01

    This specification prescribes requirements for covered corrosion-resisting chromium and chromium-nickel steel electrodes. These electrodes normally are used for shielded metal arc welding, and include those alloy steels designated as corrosion or heat-resisting chromium-nickel steels in which chromium exceeds 4.0 percent and nickel does not exceed 50.0 percent

  16. Covering Conflict and Controversy: Measuring Balance, Fairness, Defamation.

    Science.gov (United States)

    Simon, Todd F.; And Others

    1989-01-01

    Measures balance, fairness, and defamation in local stories containing controversy and covering law enforcement, education, local government, and business. Finds that most stories lack balance and that the opposing side of the controversy was not contacted in 28 percent of the instances. (RS)

  17. Global variation in woodpecker species richness shaped by tree availability

    DEFF Research Database (Denmark)

    Ilsoe, Sigrid Kistrup; Kissling, W. Daniel; Fjeldsa, Jon

    2017-01-01

    . Location: Global. Methods: We used spatial and non-spatial regressions to test for relationships between broad-scale woodpecker species richness and predictor variables describing current and deep-time availability of trees, current climate, Quaternary climate change, human impact, topographical...... a negative indirect effect on woodpecker species richness. Main conclusions: Global species richness of woodpeckers is primarily shaped by current tree cover and precipitation, reflecting a strong biotic association between woodpeckers and trees. Human influence can have a negative effect on woodpecker....... As an example, woodpeckers (Picidae) are closely associated with trees and woody habitats because of multiple morphological and ecological specializations. In this study, we test whether this strong biotic association causes woodpecker diversity to be closely linked to tree availability at a global scale...

  18. GumTree: Data reduction

    Energy Technology Data Exchange (ETDEWEB)

    Rayner, Hugh [Bragg Institute, Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia)]. E-mail: hrz@ansto.gov.au; Hathaway, Paul [Bragg Institute, Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia); Hauser, Nick [Bragg Institute, Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia); Fei, Yang [Bragg Institute, Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia); Franceschini, Ferdi [Bragg Institute, Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia); Lam, Tony [Bragg Institute, Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia)

    2006-11-15

    Access to software tools for interactive data reduction, visualisation and analysis during a neutron scattering experiment enables instrument users to make informed decisions regarding the direction and success of their experiment. ANSTO aims to enhance the experiment experience of its facility's users by integrating these data reduction tools with the instrument control interface for immediate feedback. GumTree is a software framework and application designed to support an Integrated Scientific Experimental Environment, for concurrent access to instrument control, data acquisition, visualisation and analysis software. The Data Reduction and Analysis (DRA) module is a component of the GumTree framework that allows users to perform data reduction, correction and basic analysis within GumTree while an experiment is running. It is highly integrated with GumTree, able to pull experiment data and metadata directly from the instrument control and data acquisition components. The DRA itself uses components common to all instruments at the facility, providing a consistent interface. It features familiar ISAW-based 1D and 2D plotting, an OpenGL-based 3D plotter and peak fitting performed by fityk. This paper covers the benefits of integration, the flexibility of the DRA module, ease of use for the interface and audit trail generation.

  19. GumTree: Data reduction

    International Nuclear Information System (INIS)

    Rayner, Hugh; Hathaway, Paul; Hauser, Nick; Fei, Yang; Franceschini, Ferdi; Lam, Tony

    2006-01-01

    Access to software tools for interactive data reduction, visualisation and analysis during a neutron scattering experiment enables instrument users to make informed decisions regarding the direction and success of their experiment. ANSTO aims to enhance the experiment experience of its facility's users by integrating these data reduction tools with the instrument control interface for immediate feedback. GumTree is a software framework and application designed to support an Integrated Scientific Experimental Environment, for concurrent access to instrument control, data acquisition, visualisation and analysis software. The Data Reduction and Analysis (DRA) module is a component of the GumTree framework that allows users to perform data reduction, correction and basic analysis within GumTree while an experiment is running. It is highly integrated with GumTree, able to pull experiment data and metadata directly from the instrument control and data acquisition components. The DRA itself uses components common to all instruments at the facility, providing a consistent interface. It features familiar ISAW-based 1D and 2D plotting, an OpenGL-based 3D plotter and peak fitting performed by fityk. This paper covers the benefits of integration, the flexibility of the DRA module, ease of use for the interface and audit trail generation

  20. A modeling study of the impact of urban trees on ozone

    Science.gov (United States)

    David J. Nowak; Kevin L. Civerolo; S. Trivikrama Rao; Gopal Sistla; Christopher J. Luley; Daniel E. Crane

    2000-01-01

    Modeling the effects of increased urban tree cover on ozone concentrations (July 13-15, 1995) from Washington, DC, to central Massachusetts reveals that urban trees generally reduce ozone concentrations in cities, but tend to increase average ozone concentrations in the overall modeling domain. During the daytime, average ozone reductions in urban areas (1 ppb) were...

  1. A decadal analysis of bioeroding sponge cover on the inshore Great Barrier Reef.

    Science.gov (United States)

    Ramsby, Blake D; Hoogenboom, Mia O; Whalan, Steve; Webster, Nicole S; Thompson, Angus

    2017-06-02

    Decreasing coral cover on the Great Barrier Reef (GBR) may provide opportunities for rapid growth and expansion of other taxa. The bioeroding sponges Cliona spp. are strong competitors for space and may take advantage of coral bleaching, damage, and mortality. Benthic surveys of the inshore GBR (2005-2014) revealed that the percent cover of the most abundant bioeroding sponge species, Cliona orientalis, has not increased. However, considerable variation in C. orientalis cover, and change in cover over time, was evident between survey locations. We assessed whether biotic or environmental characteristics were associated with variation in C. orientalis distribution and abundance. The proportion of fine particles in the sediments was negatively associated with the presence-absence and the percent cover of C. orientalis, indicating that the sponge requires exposed habitat. The cover of corals and other sponges explained little variation in C. orientalis cover or distribution. The fastest increases in C. orientalis cover coincided with the lowest macroalgal cover and chlorophyll a concentration, highlighting the importance of macroalgal competition and local environmental conditions for this bioeroding sponge. Given the observed distribution and habitat preferences of C. orientalis, bioeroding sponges likely represent site-specific - rather than regional - threats to corals and reef accretion.

  2. Specification for corrosion-resisting chromium and chromium-nickel steel covered welding electrodes

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    This specification prescribes requirements for covered corrosion-resisting chromium and chromium-nickel steel electrodes. These electrodes are normally used for shielded metal arc welding, and include those alloy steels designated as corrosion or heat-resisting chromium and chromium-nickel steels, in which chromium exceeds 4.0 percent and nickel does not exceed 50.0 percent

  3. Chicago's urban forest ecosystem: Results of the Chicago Urban Forest Climate Project. (Includes executive summary). Forest Service general technical report (Final)

    International Nuclear Information System (INIS)

    McPherson, E.G.; Nowak, D.J.; Rowntree, R.A.

    1994-06-01

    Results of the 3-year Chicago Urban Forest Climate Project indicate that there are an estimated 50.8 million trees in the Chicago area of Cook and DuPage Counties; 66 percent of these trees rated in good or excellent condition. During 1991, trees in the Chicago area removed an estimated 6,145 tons of air pollutants, providing air cleansing valued at $9.2 million dollars. These trees also sequester approximately 155,000 tons of carbon per year, and provide residential heating and cooling energy savings that, in turn, reduce carbon emissions from power plants by about 12,600 tons annually. Shade, lower summer air temperatures, and a reduction in windspeed associated with increasing tree cover by 10 percent can lower total heating and cooling energy use by 5 to 10 percent annually ($50 to $90 per dwelling unit). The projected net present value of investment in planting and care of 95,000 trees in Chicago is $38 million ($402 per planted tree), indicating that the long-term benefits of trees are more than twice their costs

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

    Science.gov (United States)

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

    2013-12-01

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

  5. Fungal diseases of tree stands under urbanized conditions of Moscow

    Directory of Open Access Journals (Sweden)

    Smirnova Oksana G.

    2013-01-01

    Full Text Available Phytosanitary and ecological estimation of tree-stands has been con­ducted at the Forest Experimental Station of Moscow Agricultural Academy and parks of Northeast of Moscow in 2007-2011. Fomes fomentarius was proved to be a very serious pathogen of trees under conditions of Moscow, Piptoporus betulinus, Phellinus igniarius, and Fomitopsis pinicola also occurred and caused damage to trees. This rather bad phytosanitary situation depends on alarming ecological situation in Moscow. At the Forest Experimental Station of Moscow Agricultural Academy a number and cover of lichens decreased. In general, all trees in Moscow are in dynamic equilibrium with the urbanized environment. In connection with this, the following classification of tree-stands was proposed for the urbanized environment: 1 - healthy trees, 2 - affected trees which can be managed, 3 - dry woods, 3a - very diseased. Many tree-stands in investigated regions of Moscow are found to belong to the groups 2 and 3c. All tree-stands must be carefully monitored and managed in order to provide a well-timed decision on the support system for preservation of trees as ‘lungs of city’ and avoid unpredictable tree falling which put people and traffic at risk.

  6. Factors influencing bird foraging preferences among conspecific fruit trees

    Science.gov (United States)

    Foster, M.S.

    1990-01-01

    The rates at which birds visit fruiting individuals of Allophylus edulis (Sapindaceae) differ substantially among trees. Such avian feeding preferences are well-known, but usually involve fruits and trees of different species. Factors controlling avian preferences for particular trees in a population of conspecifics are generally undocumented. To address this issue, I attempted to correlate rates at which individual birds and species fed in trees of Allophylus with 27 fruit or plant characteristics. Birds that swallow fruits whole were considered separately from those that feed in other ways. Plant characters were selected on the basis of their potential influence on feeding efficiency or predation risk, assuming that birds would select feeding trees so as to maximize the net rate of energy or nutrient intake and to minimize predation. Correlations were found between feeding visits by some groups of birds and percent water in the pulp, milligrams of mineral ash in the pulp, and crop size. No character was correlated with feeding visits by all groups of birds in both years of the study. The correlations with water and mineral ash are unexplained and may be artifacts. The correlation with crop size may represent a tactic to minimize predation.

  7. Genetic bottlenecks in agroforestry systems: results of tree nursery surveys in East Africa

    NARCIS (Netherlands)

    Lengkeek, A.G.; Jaenicke, H.; Dawson, I.K.

    2005-01-01

    Seedlings sourced through tree nurseries are expected to form an important component of future tree cover on farms. As such, the genetic composition of nursery seedlings is expected to impact on the productivity and sustainability of agroforestry ecosystems. By surveying current practices of nursery

  8. USING PRECEDENTS FOR REDUCTION OF DECISION TREE BY GRAPH SEARCH

    Directory of Open Access Journals (Sweden)

    I. A. Bessmertny

    2015-01-01

    Full Text Available The paper considers the problem of mutual payment organization between business entities by means of clearing that is solved by search of graph paths. To reduce the decision tree complexity a method of precedents is proposed that consists in saving the intermediate solution during the moving along decision tree. An algorithm and example are presented demonstrating solution complexity coming close to a linear one. The tests carried out in civil aviation settlement system demonstrate approximately 30 percent shortage of real money transfer. The proposed algorithm is planned to be implemented also in other clearing organizations of the Russian Federation.

  9. Use of Binary Partition Tree and energy minimization for object-based classification of urban land cover

    Science.gov (United States)

    Li, Mengmeng; Bijker, Wietske; Stein, Alfred

    2015-04-01

    Two main challenges are faced when classifying urban land cover from very high resolution satellite images: obtaining an optimal image segmentation and distinguishing buildings from other man-made objects. For optimal segmentation, this work proposes a hierarchical representation of an image by means of a Binary Partition Tree (BPT) and an unsupervised evaluation of image segmentations by energy minimization. For building extraction, we apply fuzzy sets to create a fuzzy landscape of shadows which in turn involves a two-step procedure. The first step is a preliminarily image classification at a fine segmentation level to generate vegetation and shadow information. The second step models the directional relationship between building and shadow objects to extract building information at the optimal segmentation level. We conducted the experiments on two datasets of Pléiades images from Wuhan City, China. To demonstrate its performance, the proposed classification is compared at the optimal segmentation level with Maximum Likelihood Classification and Support Vector Machine classification. The results show that the proposed classification produced the highest overall accuracies and kappa coefficients, and the smallest over-classification and under-classification geometric errors. We conclude first that integrating BPT with energy minimization offers an effective means for image segmentation. Second, we conclude that the directional relationship between building and shadow objects represented by a fuzzy landscape is important for building extraction.

  10. Inspiration: One Percent and Rising

    Science.gov (United States)

    Walling, Donovan R.

    2009-01-01

    Inventor Thomas Edison once famously declared, "Genius is one percent inspiration and ninety-nine percent perspiration." If that's the case, then the students the author witnessed at the International Student Media Festival (ISMF) last November in Orlando, Florida, are geniuses and more. The students in the ISMF pre-conference workshop…

  11. The Land Cover Dynamics and Conversion of Agricultural Land in Northwestern Bangladesh, 1973-2003.

    Science.gov (United States)

    Pervez, M.; Seelan, S. K.; Rundquist, B. C.

    2006-05-01

    The importance of land cover information describing the nature and extent of land resources and changes over time is increasing; this is especially true in Bangladesh, where land cover is changing rapidly. This paper presents research into the land cover dynamics of northwestern Bangladesh for the period 1973-2003 using Landsat satellite images in combination with field survey data collected in January and February 2005. Land cover maps were produced for eight different years during the study period with an average 73 percent overall classification accuracy. The classification results and post-classification change analysis showed that agriculture is the dominant land cover (occupying 74.5 percent of the study area) and is being reduced at a rate of about 3,000 ha per year. In addition, 6.7 percent of the agricultural land is vulnerable to temporary water logging annually. Despite this loss of agricultural land, irrigated agriculture increased substantially until 2000, but has since declined because of diminishing water availability and uncontrolled extraction of groundwater driven by population pressures and the extended need for food. A good agreement (r = 0.73) was found between increases in irrigated land and the depletion of the shallow groundwater table, a factor affecting widely practiced small-scale irrigation in northwestern Bangladesh. Results quantified the land cover change patterns and the stresses placed on natural resources; additionally, they demonstrated an accurate and economical means to map and analyze changes in land cover over time at a regional scale, which can assist decision makers in land and natural resources management decisions.

  12. Criterion 5: Maintenance of forest contributions to global carbon cycles

    Science.gov (United States)

    Stephen R. Shifley; Francisco X. Aguilar; Nianfu Song; Susan I. Stewart; David J. Nowak; Dale D. Gormanson; W. Keith Moser; Sherri Wormstead; Eric J. Greenfield

    2012-01-01

    Northern forests cover more than 42 percent of the region and are enormous reservoirs of carbon. Through photosynthesis, live trees emit oxygen in exchange for carbon dioxide they pull from the atmosphere. As a tree grows it stores carbon in wood above and below ground, and sequestered carbon comprises about half of its dry weight. Dead trees and down logs are also...

  13. Tree island pattern formation in the Florida Everglades

    Science.gov (United States)

    Carr, Joel; D'Odorico, P.; Engel, Victor C.; Redwine, Jed

    2016-01-01

    The Florida Everglades freshwater landscape exhibits a distribution of islands covered by woody vegetation and bordered by marshes and wet prairies. Known as “tree islands”, these ecogeomorphic features can be found in few other low gradient, nutrient limited freshwater wetlands. In the last few decades, however, a large percentage of tree islands have either shrank or disappeared in apparent response to altered water depths and other stressors associated with human impacts on the Everglades. Because the processes determining the formation and spatial organization of tree islands remain poorly understood, it is still unclear what controls the sensitivity of these landscapes to altered conditions. We hypothesize that positive feedbacks between woody plants and soil accretion are crucial to emergence and decline of tree islands. Likewise, positive feedbacks between phosphorus (P) accumulation and trees explain the P enrichment commonly observed in tree island soils. Here, we develop a spatially-explicit model of tree island formation and evolution, which accounts for these positive feedbacks (facilitation) as well as for long range competition and fire dynamics. It is found that tree island patterns form within a range of parameter values consistent with field data. Simulated impacts of reduced water levels, increased intensity of drought, and increased frequency of dry season/soil consuming fires on these feedback mechanisms result in the decline and disappearance of tree islands on the landscape.

  14. The interactive effects of surface-burn severity and canopy cover on conifer and broadleaf tree seedling ecophysiology

    Science.gov (United States)

    Sheel Bansal; Till Jochum; David A. Wardle; Marie-Charlotte Nilsson

    2014-01-01

    Fire has an important role for regeneration of many boreal forest tree species, and this includes both wildfire and prescribed burning following clear-cutting. Depending on the severity, fire can have a variety of effects on above- and belowground properties that impact tree seedling establishment. Very little is known about the impacts of ground fire severity on post-...

  15. Impact of Site Disturbances from Harvesting and Logging on Soil Physical Properties and Pinus kesiya Tree Growth.

    Science.gov (United States)

    Missanjo, Edward; Kamanga-Thole, Gift

    2014-01-01

    A study was conducted to determine the impacts of soil disturbance and compaction on soil physical properties and tree growth and the effectiveness of tillage in maintaining or enhancing site productivity for intensively managed Pinus kesiya Royle ex Gordon sites in Dedza, Malawi. The results indicate that about fifty-two percent of the area of compacted plots was affected by the vehicular traffic. Seventy percent of the trees were planted on microsites with some degree of soil disturbance. Soil bulk density at 0-20 cm depth increased from 0.45 to 0.66 Mg m(-3) in the most compacted portions of traffic lanes. Soil strength in traffic lanes increased at all 60 cm depth but never exceeded 1200 kPa. Volumetric soil water content in compacted traffic lanes was greater than that in noncompacted soil. Total soil porosity decreased 13.8% to 16.1% with compaction, while available water holding capacity increased. The study revealed no detrimental effects on tree height and diameter from soil disturbance or compaction throughout the three growing season. At the ages of two and three, a tree volume index was actually greater for trees planted on traffic lanes than those on nondisturbed soil.

  16. Rangeland monitoring using remote sensing: comparison of cover estimates from field measurements and image analysis

    Directory of Open Access Journals (Sweden)

    Ammon Boswell

    2017-01-01

    Full Text Available Rangeland monitoring is important for evaluating and assessing semi-arid plant communities. Remote sensing provides an effective tool for rapidly and accurately assessing rangeland vegetation and other surface attributes such as bare soil and rock. The purpose of this study was to evaluate the efficacy of remote sensing as a surrogate for field-based sampling techniques in detecting ground cover features (i.e., trees, shrubs, herbaceous cover, litter, surface, and comparing results with field-based measurements collected by the Utah Division of Wildlife Resources Range Trent Program. In the field, five 152 m long transects were used to sample plant, litter, rock, and bare-ground cover using the Daubenmire ocular estimate method. At the same location of each field plot, a 4-band (R,G,B,NIR, 25 cm pixel resolution, remotely sensed image was taken from a fixed-wing aircraft. Each image was spectrally classified producing 4 cover classes (tree, shrub, herbaceous, surface. No significant differences were detected between canopy cover collected remotely and in the field for tree (P = 0.652, shrub (P = 0.800, and herbaceous vegetation (P = 0.258. Surface cover was higher in field plots (P < 0.001, likely in response to the methods used to sample surface features by field crews. Accurately classifying vegetation and other features from remote sensed information can improve the efficiency of collecting vegetation and surface data. This information can also be used to improve data collection frequency for rangeland monitoring and to efficiently quantify ecological succession patterns.

  17. Rubber and Land-Cover Land-Use Change in Mainland Southeast Asia

    Science.gov (United States)

    Fox, J. M.; Hurni, K.

    2017-12-01

    Over the past half century, the five countries of Mainland Southeast Asia (MSEA) - Cambodia, Laos, Myanmar, Thailand, and Vietnam - have witnessed major shifts from predominantly subsistence agrarian economies to increasingly commercialized agriculture. Major drivers of change include policy initiatives that fostered regional economic integration and promoted among other changes rapid expansion of boom-crop plantations. Among the many types of commercial boom crops promoted and grown in MSEA are numerous tree-based products such as rubber, coffee, tree species for pulp and paper (particularly eucalyptus and acacia), cashews, and fruits such as oranges, lychees, and longans. The project proposal hypothesized that most (but not all) tree crops replaced swidden cultivation fields and hence are not necessarily accompanied by deforestation. We used MODIS EVI and SWIR time-series from 2001-2014 to classify changes in tree cover across MSEA; a total of 6849 sample points were used to train the classifier (75%) and verification (25%). The classification consists of 24 classes and 17 classes represent tree crops. Project results suggest that 4.4 m ha of rubber have been planted since 2003; 50% of rubber is planted on former evergreen forest land, 18% on deciduous forest land, and 32% on low vegetation area (former crop lands, bushes, scrub). Tree crops occupy about 8% of the landscape (half of that is rubber). Due to the differences in their political and economic histories these countries display different LCLUCs. In northern Laos, smallholder rubber plantations dominate and shifting cultivation is common in the upland. In southern Laos, large-scale plantations of rubber, coffee, eucalyptus, and sugarcane are widespread. In Thailand, vast areas are covered by annual agriculture; fruit trees and rubber are the prevailing tree crops and are mostly planted by smallholders. In Cambodia, large-scale rubber plantations have expanded in recent years on forest lands; smallholder

  18. Verification of a Novel Method of Detecting Faults in Medium-Voltage Systems with Covered Conductors

    Directory of Open Access Journals (Sweden)

    Mišák Stanislav

    2017-06-01

    Full Text Available This paper describes the use of new methods of detecting faults in medium-voltage overhead lines built of covered conductors. The methods mainly address such faults as falling of a conductor, contacting a conductor with a tree branch, or falling a tree branch across three phases of a medium-voltage conductor. These faults cannot be detected by current digital relay protection systems. Therefore, a new system that can detect the above mentioned faults was developed. After having tested its operation, the system has already been implemented to protect mediumvoltage overhead lines built of covered conductors.

  19. Residential building energy conservation and avoided power plant emissions by urban and community trees in the United States

    Science.gov (United States)

    David J. Nowak; Nathaniel Appleton; Alexis Ellis; Eric Greenfield

    2017-01-01

    Urban trees and forests alter building energy use and associated emissions from power plants by shading buildings, cooling air temperatures and altering wind speeds around buildings. Field data on urban trees were combined with local urban/community tree and land cover maps, modeling of tree effects on building energy use and pollutant emissions, and state energy and...

  20. Progress report to the International Fruit Tree Association

    Science.gov (United States)

    This report provides an update on several projects that are fostered by the International Fruit Tree Association which covers some aspects of rootstock development, performance in the orchard and to address nursery industry needs. The report highlights results from graft union strength experiments,...

  1. Establishment of trees and shrubs on lands disturbed by mining in the West

    Science.gov (United States)

    Ardell J. Bjugstad

    1984-01-01

    Increased research and development of cultural practices and species has assured success of establishment of trees and shrubs on lands disturbed by surface mining. Trickle irrigation and water harvesting techniques have increased survival of planted stock by 250 percent for some species.

  2. Trees in urban parks and forests reduce O3, but not NO2 concentrations in Baltimore, MD, USA

    Science.gov (United States)

    Yli-Pelkonen, Vesa; Scott, Anna A.; Viippola, Viljami; Setälä, Heikki

    2017-10-01

    Trees and other vegetation absorb and capture air pollutants, leading to the common perception that they, and trees in particular, can improve air quality in cities and provide an important ecosystem service for urban inhabitants. Yet, there has been a lack of empirical evidence showing this at the local scale with different plant configurations and climatic regions. We studied the impact of urban park and forest vegetation on the levels of nitrogen dioxide (NO2) and ground-level ozone (O3) while controlling for temperature during early summer (May) using passive samplers in Baltimore, USA. Concentrations of O3 were significantly lower in tree-covered habitats than in adjacent open habitats, but concentrations of NO2 did not differ significantly between tree-covered and open habitats. Higher temperatures resulted in higher pollutant concentrations and NO2 and O3 concentration were negatively correlated with each other. Our results suggest that the role of trees in reducing NO2 concentrations in urban parks and forests in the Mid-Atlantic USA is minor, but that the presence of tree-cover can result in lower O3 levels compared to similar open areas. Our results further suggest that actions aiming at local air pollution mitigation should consider local variability in vegetation, climate, micro-climate, and traffic conditions.

  3. Recovery of endemic dragonflies after removal of invasive alien trees.

    Science.gov (United States)

    Samways, Michael J; Sharratt, Norma J

    2010-02-01

    Because dragonflies are very sensitive to alien trees, we assessed their response to large-scale restoration of riparian corridors. We compared three types of disturbance regime--alien invaded, cleared of alien vegetation, and natural vegetation (control)--and recorded data on 22 environmental variables. The most significant variables in determining dragonfly assemblages were percentage of bank cover and tree canopy cover, which indicates the importance of vegetation architecture for these dragonflies. This finding suggests that it is important to restore appropriate marginal vegetation and sunlight conditions. Recovery of dragonfly assemblages after the clearing of alien trees was substantial. Species richness and abundance at restored sites matched those at control sites. Dragonfly assemblage patterns reflected vegetation succession. Thus, initially eurytopic, widespread species were the main beneficiaries of the removal of alien trees, and stenotopic, endemic species appeared after indigenous vegetation recovered over time. Important indicator species were the two national endemics (Allocnemis leucosticta and Pseudagrion furcigerum), which, along with vegetation type, can be used to monitor return of overall integrity of riparian ecology and to make management decisions. Endemic species as a whole responded positively to restoration, which suggests that indigenous vegetation recovery has major benefits for irreplaceable and widespread generalist species.

  4. Integrating the effects of forest cover on slope stability in a deterministic landslide susceptibility model (TRIGRS 2.0)

    Science.gov (United States)

    Zieher, T.; Rutzinger, M.; Bremer, M.; Meissl, G.; Geitner, C.

    2014-12-01

    The potentially stabilizing effects of forest cover in respect of slope stability have been the subject of many studies in the recent past. Hence, the effects of trees are also considered in many deterministic landslide susceptibility models. TRIGRS 2.0 (Transient Rainfall Infiltration and Grid-Based Regional Slope-Stability; USGS) is a dynamic, physically-based model designed to estimate shallow landslide susceptibility in space and time. In the original version the effects of forest cover are not considered. As for further studies in Vorarlberg (Austria) TRIGRS 2.0 is intended to be applied in selected catchments that are densely forested, the effects of trees on slope stability were implemented in the model. Besides hydrological impacts such as interception or transpiration by tree canopies and stems, root cohesion directly influences the stability of slopes especially in case of shallow landslides while the additional weight superimposed by trees is of minor relevance. Detailed data on tree positions and further attributes such as tree height and diameter at breast height were derived throughout the study area (52 km²) from high-resolution airborne laser scanning data. Different scenarios were computed for spruce (Picea abies) in the study area. Root cohesion was estimated area-wide based on published correlations between root reinforcement and distance to tree stems depending on the stem diameter at breast height. In order to account for decreasing root cohesion with depth an exponential distribution was assumed and implemented in the model. Preliminary modelling results show that forest cover can have positive effects on slope stability yet strongly depending on tree age and stand structure. This work has been conducted within C3S-ISLS, which is funded by the Austrian Climate and Energy Fund, 5th ACRP Program.

  5. The distribution on trees of dry deposited material from the Chernobyl accident

    International Nuclear Information System (INIS)

    Roed, J.

    1988-01-01

    The distribution of material from the Chernobyl accident that has been dry deposited on forest trees near Roskilde (Denmark) and on trees in a suburban area of Roskilde are investigated. The dry deposition velocities on the plan-projected area covered by the trees are found and compared with those on paved surfaces. The conclusion is that the deposited material is distributed fairly uniformly on the trees, and that the deposition velocities on trees are more than 10 times higher than on paved surfaces. A bulk deposition constant is defined and proposed to be used for modelling the deposition on trees in an urban environment. This work was supported by the EEC Radiation Protection Programme under contract No. B16-107-DK and by NKA, the Nordic Liaison Committee for Atomic Energy

  6. Influence of Inter stock Grafting as a Dwarfing Component on Peach Trees Development and Fruit Quality

    International Nuclear Information System (INIS)

    Hossain, S.; Nasrulhaq, A.; Mizutani, F.

    2006-01-01

    A field experiment was conducted to investigate the interstock grafting effect as a dwarfing component on Peach tree development and fruit quality. The study was made at the Ehime University Experimental farm located in south-eastern Japan during the period 2001-2005. The results of the field experiment indicated that pruned branches weight and flowers number were lower in interstock than in control trees. However, percent fruit set was a little higher in intersrock treated than in control trees. Fruit yield and fruit weight were lower in interstock treated than control trees. Soluble solids content and maturity index were higher in interstock treated trees than control, with an increasing trend in the period from 2001 to 2005, while titratable acidity showed that the livestock grafting is a useful dwarfing component for controlling the size of peach trees and improvement of fruit quality. (author)

  7. Assessing urban forest effects and values, Scranton's urban forest

    Science.gov (United States)

    David J. Nowak; Robert E. III Hoehn; Daniel E. Crane; Jack C. Stevens; Vincent. Cotrone

    2010-01-01

    An analysis of trees in the urbanized portion of Scranton, PA, reveals that this area has about 1.2 million trees with canopies that cover 22.0 percent of the area. The most common tree species are red maple, gray birch, black cherry, northern red oak, and quaking aspen. Scranton's urban forest currently store about 93,300 tons of carbon valued at $1.9 million. In...

  8. Perch availability and ground cover: factors that may constitute ...

    African Journals Online (AJOL)

    In Succulent Karoe, pale chanting goshawks occupied areas where perch density (16 natural and 122 artificial/25 hal was significantly higher than in unoccupied areas (8 natural and 12 artificial/25 hal. The high proportion of cover formed by natural perches (trees and shrubs; 36%) and the low proportion of open ground ...

  9. Percent Agricultural Land Cover on Steep Slopes

    Data.gov (United States)

    U.S. Environmental Protection Agency — Clearing land for agriculture tends to increase soil erosion. The amount of erosion is related to the steepness of the slope, farming methods used and soil type....

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

    Science.gov (United States)

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

    2015-03-15

    Recent studies have shown a considerable increase in the abundance of rowan (Sorbus aucuparia) saplings in urban forests in Finland, yet the reasons for this increase are not well understood. Here we investigated whether canopy cover or tree species composition, i.e., the basal areas of different tree species in Norway spruce dominated urban forests, affects the abundances of rowan seedlings, saplings and trees. Altogether 24 urban forest patches were investigated. We sampled the number of rowan and other saplings, and calculated the basal areas of trees. We showed that rowan abundance was affected by tree species composition. The basal area of rowan trees (≥ 5 cm in diameter at breast height, dbh) decreased with increasing basal area of Norway spruce, while the cover of rowan seedlings increased with an increase in Norway spruce basal area. However, a decrease in the abundance of birch (Betula pendula) and an increase in the broad-leaved tree group (Acer platanoides, Alnus glutinosa, Alnus incana, Amelanchier spicata, Prunus padus, Quercus robur, Rhamnus frangula and Salix caprea) coincided with a decreasing number of rowans. Furthermore, rowan saplings were scarce in the vicinity of mature rowan trees. Although it seems that tree species composition has an effect on rowan, the relationship between rowan saplings and mature trees is complex, and therefore we conclude that regulating tree species composition is not an easy way to keep rowan thickets under control in urban forests in Finland. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Assessment of ecosystem services provided by urban trees: public lands within the Urban Growth Boundary of Corvallis, OR

    Science.gov (United States)

    Public lands within the Urban Growth Boundary of Corvallis, Oregon contain a diverse population of about 440,000 trees that include over 300 varieties and have an estimated tree cover of 31%. While often unrecognized, urban trees provide a variety of “ecosystem services” or dire...

  12. Stem analysis program (GOAP for evaluating of increment and growth data at individual tree

    Directory of Open Access Journals (Sweden)

    Gafura Aylak Özdemir

    2016-07-01

    Full Text Available Stem analysis is a method evaluating in a detailed way data of increment and growth of individual tree at the past periods and widely used in various forestry disciplines. Untreated data of stem analysis consist of annual ring count and measurement procedures performed on cross sections taken from individual tree by section method. The evaluation of obtained this untreated data takes quite some time. Thus, a computer software was developed in this study to quickly and efficiently perform stem analysis. This computer software developed to evaluate untreated data of stem analysis as numerical and graphical was programmed as macro by utilizing Visual Basic for Application feature of MS Excel 2013 program currently the most widely used. In developed this computer software, growth height model is formed from two different approaches, individual tree volume depending on section method, cross-sectional area, increments of diameter, height and volume, volume increment percent and stem form factor at breast height are calculated depending on desired period lengths. This calculated values are given as table. Development of diameter, height, volume, increments of these variables, volume increment percent and stem form factor at breast height according to periodic age are given as chart. Stem model showing development of diameter, height and shape of individual tree in the past periods also can be taken from computer software as chart.

  13. Ecological Weed Management by Cover Cropping: Effect on Winter Weeds and Summer Weeds Establishment in Potato

    Directory of Open Access Journals (Sweden)

    M Ghaffari

    2012-07-01

    Full Text Available Now a day winter cover crops planting has been attended to reduce herbicide application. An experiment was carried out at the Research Farm of Agriculture Faculty, Bu- Ali Sina, University, in 2009. The experiment was a randomized complete block design with three replications. The trial included of five treatments consists of no cover crop, rye, winter oilseed rape, barley and triticale. The results showed that winter cereals were produced more biomass than winter oilseed rape. living mulch of rye, barley, oilseed rape and triticale reduced winter weeds biomass 89, 86, 82 and 70 percent respectively, in compare to control. Cover crop treatments showed significant different weeds control of potato at 3 time (15, 45 and 75 DAPG compare to control treatment. Residues mixed to soil of oilseed rape and rye had the most inhibition affects on summer weeds. These treatments, average weeds biomass decreased 61 and 57 percent respectively, in compare to control. Oilseed rape and rye in compare to control reduced weeds density in potato 36 and 35 percent, respectively. Significant negation correlations of weeds plant population, weeds dry matter with average tuber weight and potato yield. The treatments, oilseed rape and rye in compare to control increased tuber yield of potato 54 and 50 percent, respectively. These treatments, the average tuber weight increased 74 and 38 percent in compare with control, respectively.

  14. Monitoring stress-related mass variations in Amazon trees using accelerometers

    Science.gov (United States)

    van Emmerik, T. H. M.; Steele-Dunne, S. C.; Gentine, P.; Hut, R.; Guerin, M. F.; Leus, G.; Oliveira, R. S.; Van De Giesen, N.

    2016-12-01

    Containing half of the world's rainforests, the Amazon plays a key role in the global water and carbon budget. However, the Amazon remains poorly understood, but appears to be vulnerable to increasing moisture stress, and future droughts have the potential to considerably change the global water and carbon budget. Field measurements will allow further investigations of the effects of moisture stress and droughts on tree dynamics, and its impact on the water and carbon budget. This study focuses on studying the diurnal mass variations of seven Amazonian tree species. The mass of trees is influenced by physiological processes within the tree (e.g. transpiration and root water uptake), as well as external loads (e.g. intercepted precipitation). Depending on the physiological traits of an individual tree, moisture stress and drought affect processes such as photosynthesis, assimilation, transpiration, and root water uptake. In turn, these have their influence on diurnal mass variations of a tree. Our study uses measured three-dimensional displacement and acceleration of trees, to detect and quantify their diurnal (bio)mass variations. Nineteen accelerometers and dendrometers were installed on seven different tree species in the Amazon rainforest, covering an area of 250 x 250 m. The selected species span a wide range in wood density (0.5 - 1.1), diameter (15 - 40 cm) and height (25 - 60 m). Acceleration was measured with a frequency of 10 Hz, from August 2015 to June 2016, covering both the wet and dry season. On-site additional measurements of net radiation, wind speed at three heights, temperature, and precipitation as available every 15 minutes. Dendrometers measured variation in xylem and bark thickness every 5 minutes. The MUltiple SIgnal Classification (MUSIC) algorithm was applied to the acceleration time series to estimate the frequency spectrum of each tree. A correction was necessary to account for the dominant effect of wind. The resulting spectra reveal

  15. Boundary expansion algorithm of a decision tree induction for an imbalanced dataset

    Directory of Open Access Journals (Sweden)

    Kesinee Boonchuay

    2017-10-01

    Full Text Available A decision tree is one of the famous classifiers based on a recursive partitioning algorithm. This paper introduces the Boundary Expansion Algorithm (BEA to improve a decision tree induction that deals with an imbalanced dataset. BEA utilizes all attributes to define non-splittable ranges. The computed means of all attributes for minority instances are used to find the nearest minority instance, which will be expanded along all attributes to cover a minority region. As a result, BEA can successfully cope with an imbalanced dataset comparing with C4.5, Gini, asymmetric entropy, top-down tree, and Hellinger distance decision tree on 25 imbalanced datasets from the UCI Repository.

  16. VEGETATION COVER ANALYSIS OF HAZARDOUS WASTE SITES IN UTAH AND ARIZONA USING HYPERSPECTRAL REMOTE SENSING

    Energy Technology Data Exchange (ETDEWEB)

    Serrato, M.; Jungho, I.; Jensen, J.; Jensen, R.; Gladden, J.; Waugh, J.

    2012-01-17

    Remote sensing technology can provide a cost-effective tool for monitoring hazardous waste sites. This study investigated the usability of HyMap airborne hyperspectral remote sensing data (126 bands at 2.3 x 2.3 m spatial resolution) to characterize the vegetation at U.S. Department of Energy uranium processing sites near Monticello, Utah and Monument Valley, Arizona. Grass and shrub species were mixed on an engineered disposal cell cover at the Monticello site while shrub species were dominant in the phytoremediation plantings at the Monument Valley site. The specific objectives of this study were to: (1) estimate leaf-area-index (LAI) of the vegetation using three different methods (i.e., vegetation indices, red-edge positioning (REP), and machine learning regression trees), and (2) map the vegetation cover using machine learning decision trees based on either the scaled reflectance data or mixture tuned matched filtering (MTMF)-derived metrics and vegetation indices. Regression trees resulted in the best calibration performance of LAI estimation (R{sup 2} > 0.80). The use of REPs failed to accurately predict LAI (R{sup 2} < 0.2). The use of the MTMF-derived metrics (matched filter scores and infeasibility) and a range of vegetation indices in decision trees improved the vegetation mapping when compared to the decision tree classification using just the scaled reflectance. Results suggest that hyperspectral imagery are useful for characterizing biophysical characteristics (LAI) and vegetation cover on capped hazardous waste sites. However, it is believed that the vegetation mapping would benefit from the use of 1 higher spatial resolution hyperspectral data due to the small size of many of the vegetation patches (< 1m) found on the sites.

  17. Vegetation Cover Analysis of Hazardous Waste Sites in Utah and Arizona Using Hyperspectral Remote Sensing

    Directory of Open Access Journals (Sweden)

    Mike Serrato

    2012-01-01

    Full Text Available This study investigated the usability of hyperspectral remote sensing for characterizing vegetation at hazardous waste sites. The specific objectives of this study were to: (1 estimate leaf-area-index (LAI of the vegetation using three different methods (i.e., vegetation indices, red-edge positioning (REP, and machine learning regression trees, and (2 map the vegetation cover using machine learning decision trees based on either the scaled reflectance data or mixture tuned matched filtering (MTMF-derived metrics and vegetation indices. HyMap airborne data (126 bands at 2.3 × 2.3 m spatial resolution, collected over the U.S. Department of Energy uranium processing sites near Monticello, Utah and Monument Valley, Arizona, were used. Grass and shrub species were mixed on an engineered disposal cell cover at the Monticello site while shrub species were dominant in the phytoremediation plantings at the Monument Valley site. Regression trees resulted in the best calibration performance of LAI estimation (R2 > 0.80. The use of REPs failed to accurately predict LAI (R2 < 0.2. The use of the MTMF-derived metrics (matched filter scores and infeasibility and a range of vegetation indices in decision trees improved the vegetation mapping when compared to the decision tree classification using just the scaled reflectance. Results suggest that hyperspectral imagery are useful for characterizing biophysical characteristics (LAI and vegetation cover on capped hazardous waste sites. However, it is believed that the vegetation mapping would benefit from the use of higher spatial resolution hyperspectral data due to the small size of many of the vegetation patches ( < 1 m found on the sites.

  18. Vegetation Cover Analysis Of Hazardous Waste Sites In Utah And Arizona Using Hyperspectral Remote Sensing

    International Nuclear Information System (INIS)

    Serrato, M.; Jungho, I.; Jensen, J.; Jensen, R.; Gladden, J.; Waugh, J.

    2012-01-01

    Remote sensing technology can provide a cost-effective tool for monitoring hazardous waste sites. This study investigated the usability of HyMap airborne hyperspectral remote sensing data (126 bands at 2.3 x 2.3 m spatial resolution) to characterize the vegetation at U.S. Department of Energy uranium processing sites near Monticello, Utah and Monument Valley, Arizona. Grass and shrub species were mixed on an engineered disposal cell cover at the Monticello site while shrub species were dominant in the phytoremediation plantings at the Monument Valley site. The specific objectives of this study were to: (1) estimate leaf-area-index (LAI) of the vegetation using three different methods (i.e., vegetation indices, red-edge positioning (REP), and machine learning regression trees), and (2) map the vegetation cover using machine learning decision trees based on either the scaled reflectance data or mixture tuned matched filtering (MTMF)-derived metrics and vegetation indices. Regression trees resulted in the best calibration performance of LAI estimation (R 2 > 0.80). The use of REPs failed to accurately predict LAI (R 2 < 0.2). The use of the MTMF-derived metrics (matched filter scores and infeasibility) and a range of vegetation indices in decision trees improved the vegetation mapping when compared to the decision tree classification using just the scaled reflectance. Results suggest that hyperspectral imagery are useful for characterizing biophysical characteristics (LAI) and vegetation cover on capped hazardous waste sites. However, it is believed that the vegetation mapping would benefit from the use of 1 higher spatial resolution hyperspectral data due to the small size of many of the vegetation patches (< 1m) found on the sites.

  19. Assessment of tree toxicity near the F- and H-Area seepage basins of the Savannah River Site

    International Nuclear Information System (INIS)

    Loehle, C.; Richardson, C.J.

    1990-12-01

    Areas of tree mortality, originating in 1979, have been documented downslope of the F- and H-Area Seepage Basins. The basins were used as discharge areas for low-level radioactive and nonradioactive waste. Preliminary studies indicated that there are three possible causes of stress: altered hydrology; hazardous chemicals; and nonhazardous chemicals. It was originally hypothesized that the most likely hydrological stressors to Nyssa sylvatica var. biflora were flooding where water levels cover the lenticels for more than 26 percent of the growing season, resulting in low oxygen availability, and toxins produced under anaerobic conditions. In fact, trees began to show stress only flowing a drought year (1977) rather than a wet year. Dry conditions could exacerbate stress by concentrating contaminants, particularly salt. Study of the soil and water chemical parameters in the impacted sites indicated that salt concentrations in the affected areas have produced abnormally high exchangeable sodium percentages. Furthermore, significantly elevated concentrations of heavy metals were found in each impacted site, although no one metal was consistently elevated. Evaluation of the concentrations of various chemicals toxic to Nyssa sylvatica var. biflora revealed that aluminum was probably the most toxic in the F-Area. Manganese, cadmium, and zinc had concentrations great enough to be considered possible causes of tree mortality in the F-Area. Aluminum was the most likely cause of mortality in the H-Area. Controlled experiments testing metal and salt concentration effects on Nyssa sylvatica would be needed to specifically assign cause and effect mortality relationships

  20. Assessment of tree toxicity near the F- and H-Area seepage basins of the Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Loehle, C. (ed.) (Westinghouse Savannah River Co., Aiken, SC (USA)); Richardson, C.J. (ed.); Greenwood, K.P.; Hane, M.E.; Lander, A.J. (Duke Univ., Durham, NC (USA))

    1990-12-01

    Areas of tree mortality, originating in 1979, have been documented downslope of the F- and H-Area Seepage Basins. The basins were used as discharge areas for low-level radioactive and nonradioactive waste. Preliminary studies indicated that there are three possible causes of stress: altered hydrology; hazardous chemicals; and nonhazardous chemicals. It was originally hypothesized that the most likely hydrological stressors to Nyssa sylvatica var. biflora were flooding where water levels cover the lenticels for more than 26 percent of the growing season, resulting in low oxygen availability, and toxins produced under anaerobic conditions. In fact, trees began to show stress only flowing a drought year (1977) rather than a wet year. Dry conditions could exacerbate stress by concentrating contaminants, particularly salt. Study of the soil and water chemical parameters in the impacted sites indicated that salt concentrations in the affected areas have produced abnormally high exchangeable sodium percentages. Furthermore, significantly elevated concentrations of heavy metals were found in each impacted site, although no one metal was consistently elevated. Evaluation of the concentrations of various chemicals toxic to Nyssa sylvatica var. biflora revealed that aluminum was probably the most toxic in the F-Area. Manganese, cadmium, and zinc had concentrations great enough to be considered possible causes of tree mortality in the F-Area. Aluminum was the most likely cause of mortality in the H-Area. Controlled experiments testing metal and salt concentration effects on Nyssa sylvatica would be needed to specifically assign cause and effect mortality relationships.

  1. LIDAR forest inventory with single-tree, double- and single-phase procedures

    Science.gov (United States)

    Robert C. Parker; David L. Evans

    2009-01-01

    Light Detection and Ranging (LIDAR) data at 0.5- to 2-m postings were used with doublesample, stratified inventory procedures involving single-tree attribute relationships in mixed, natural, and planted species stands to yield sampling errors (one-half the confidence interval expressed as a percentage of the mean) ranging from ±2.1 percent to ±11.5...

  2. Beyond Marbles: Percent Change and Social Justice

    Science.gov (United States)

    Denny, Flannery

    2013-01-01

    In the author's eighth year of teaching, she hit a wall teaching percent change. Percent change is one of the few calculations taught in math classes that shows up regularly in the media, and one that she often does in her head to make sense of the world around her. Despite this, she had been teaching percent change using textbook problems about…

  3. Rehabilitation of Understocked Loblolly-Shortleaf Pine Stands - II. Development of Intermediate and Suppressed Trees Following Release in Natural Stands

    Science.gov (United States)

    James B. Baker; Michael G. Shelton

    1998-01-01

    Development of 86 intermediate and suppressed loblolly pine (Pinus taeda L.) trees, that had been recently released from overtopping pines and hardwoods, was monitored over a 15 year period. The trees were growing in natural stands on good sites (site index = 90 ft at 50 years) that had been recently cut to stocking levels ranging from 10 to 50 percent. At time of...

  4. BGCI’s Rrole in co-ordinating a botanic garden-centred global system for the conservation of all tree diversity

    Science.gov (United States)

    Paul Smith

    2017-01-01

    It is estimated that there are at least 60,000 tree species globally and that more than 20 percent of them are threatened with extinction. This threatened tree diversity will have a critical impact for solving some of this century’s major challenges in the areas of energy, water scarcity, human health, food security, climate change and habitat degradation. Botanic...

  5. Gauge and Gravity Amplitudes from Trees to Loops

    DEFF Research Database (Denmark)

    Huang, Rijun

    This thesis describes two subjects that I mainly work on during my PhD study. They are both about scattering amplitudes, covering gravity and gauge theories, tree and loop level, with or without supersymmetry. The rst subject is Kawai-Lewellen-Tye(KLT) relation in field theory, which mysteriously...

  6. Mapping forest tree species over large areas with partially cloudy Landsat imagery

    Science.gov (United States)

    Turlej, K.; Radeloff, V.

    2017-12-01

    Forests provide numerous services to natural systems and humankind, but which services forest provide depends greatly on their tree species composition. That makes it important to track not only changes in forest extent, something that remote sensing excels in, but also to map tree species. The main goal of our work was to map tree species with Landsat imagery, and to identify how to maximize mapping accuracy by including partially cloudy imagery. Our study area covered one Landsat footprint (26/28) in Northern Wisconsin, USA, with temperate and boreal forests. We selected this area because it contains numerous tree species and variable forest composition providing an ideal study area to test the limits of Landsat data. We quantified how species-level classification accuracy was affected by a) the number of acquisitions, b) the seasonal distribution of observations, and c) the amount of cloud contamination. We classified a single year stack of Landsat-7, and -8 images data with a decision tree algorithm to generate a map of dominant tree species at the pixel- and stand-level. We obtained three important results. First, we achieved producer's accuracies in the range 70-80% and user's accuracies in range 80-90% for the most abundant tree species in our study area. Second, classification accuracy improved with more acquisitions, when observations were available from all seasons, and is the best when images with up to 40% cloud cover are included. Finally, classifications for pure stands were 10 to 30 percentage points better than those for mixed stands. We conclude that including partially cloudy Landsat imagery allows to map forest tree species with accuracies that were previously only possible for rare years with many cloud-free observations. Our approach thus provides important information for both forest management and science.

  7. Indicators of streamflow alteration, habitat fragmentation, impervious cover, and water quality for Massachusetts stream basins

    Science.gov (United States)

    Weiskel, Peter K.; Brandt, Sara L.; DeSimone, Leslie A.; Ostiguy, Lance J.; Archfield, Stacey A.

    2010-01-01

    Plymouth-Carver region, respectively, reflecting the historical reliance of Massachusetts industry upon water power and agricultural water-management practices in southeastern Massachusetts. Impervious cover is a frequently used indicator of urban land use. About 33 percent of the state’s 1,429 subbasins and groundwater contributing areas are relatively undeveloped at the local scale, with a local impervious cover of less than 4 percent. About 18 percent of Massachusetts subbasins and contributing areas are highly developed, with a local impervious cover greater than 16 percent. The remaining 49 percent of subbasins and contributing areas have levels of urban development between these extremes (4 to 16 percent local impervious cover). Cumulative impervious cover, defined for the entire upstream area encompassed by each subbasin, shows a smaller range (0 to 55 percent) than local impervious cover. Both local and cumulative impervious cover were highest in metropolitan Boston and other urban centers. High elevated impervious-cover values were also found along major transportation corridors. The water-quality status of Massachusetts streams is assessed periodically by the Massachusetts Department of Environmental Protection pursuant to the requirements of the Federal Clean Water Act. Streams selected for assessment are commonly located in larger subbasins where some degree of impairment is expected. In the 72 percent of the state’s subbasins and groundwater contributing areas with assessed streams in 2002, more than 50 percent of the assessed stream miles were considered impaired. All of the assessed stream miles were considered impaired in 66 percent of the subbasins and groundwater contributing areas with assessed streams. Large streams, such as the main stems of rivers that make up most of the assessed stream miles, also are in many cases the receiving waters for treated wastewater discharges and for this reason may be more susceptible to water-quality impairments than

  8. Wall-to-wall tree type classification using airborne lidar data and CIR images

    DEFF Research Database (Denmark)

    Schumacher, Johannes; Nord-Larsen, Thomas

    2014-01-01

    analysed at the individual tree level (object-based). However, due to computational challenges, most object-based studies cover only smaller areas and experience of larger areas is lacking. We present an approach for an object-based, unsupervised classification of trees into broadleaf or conifer using......-based classification of the TST plots showed an overall accuracy of 84% and a kappa coefficient () of 0.61 when using all plots, and 92% and 0.79, respectively, when leaving out plots with larch. NFI plots were assigned to conifer- or broadleaf-dominated or mixed depending on the area covered by the segments...... of the two tree types. In areas where lidar data were collected specifically during leaf-off conditions, 71% of the NFI plots were assigned correctly into the three categories with = 0.53. Using only NFI plots dominated by one type (broadleaf or conifer), 78% were categorized correctly with = 0...

  9. Categorizing ideas about trees: a tree of trees.

    Science.gov (United States)

    Fisler, Marie; Lecointre, Guillaume

    2013-01-01

    The aim of this study is to explore whether matrices and MP trees used to produce systematic categories of organisms could be useful to produce categories of ideas in history of science. We study the history of the use of trees in systematics to represent the diversity of life from 1766 to 1991. We apply to those ideas a method inspired from coding homologous parts of organisms. We discretize conceptual parts of ideas, writings and drawings about trees contained in 41 main writings; we detect shared parts among authors and code them into a 91-characters matrix and use a tree representation to show who shares what with whom. In other words, we propose a hierarchical representation of the shared ideas about trees among authors: this produces a "tree of trees." Then, we categorize schools of tree-representations. Classical schools like "cladists" and "pheneticists" are recovered but others are not: "gradists" are separated into two blocks, one of them being called here "grade theoreticians." We propose new interesting categories like the "buffonian school," the "metaphoricians," and those using "strictly genealogical classifications." We consider that networks are not useful to represent shared ideas at the present step of the study. A cladogram is made for showing who is sharing what with whom, but also heterobathmy and homoplasy of characters. The present cladogram is not modelling processes of transmission of ideas about trees, and here it is mostly used to test for proximity of ideas of the same age and for categorization.

  10. Tree regeneration following drought- and insect-induced mortality in piñon-juniper woodlands.

    Science.gov (United States)

    Redmond, Miranda D; Barger, Nichole N

    2013-10-01

    Widespread piñon (Pinus edulis) mortality occurred across the southwestern USA during 2002-2003 in response to drought and bark beetle infestations. Given the recent mortality and changes in regional climate over the past several decades, there is a keen interest in post-mortality regeneration dynamics in piñon-juniper woodlands. Here, we examined piñon and Utah juniper (Juniperus osteosperma) recruitment at 30 sites across southwestern Colorado, USA that spanned a gradient of adult piñon mortality levels (10-100%) to understand current regeneration dynamics. Piñon and juniper recruitment was greater at sites with more tree and shrub cover. Piñon recruitment was more strongly facilitated than juniper recruitment by trees and shrubs. New (post-mortality) piñon recruitment was negatively affected by recent mortality. However, mortality had no effect on piñon advanced regeneration (juveniles established pre-mortality) and did not shift juvenile piñon dominance. Our results highlight the importance of shrubs and juniper trees for the facilitation of piñon establishment and survival. Regardless of adult piñon mortality levels, areas with low tree and shrub cover may become increasingly juniper dominated as a result of the few suitable microsites for piñon establishment and survival. In areas with high piñon mortality and high tree and shrub cover, our results suggest that piñon is regenerating via advanced regeneration. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

  11. Anomalous diffusion in a lattice-gas wind-tree model

    International Nuclear Information System (INIS)

    Kong, X.P.; Cohen, E.G.D.

    1989-01-01

    Two new strictly deterministic lattice-gas automata derived from Ehrenfest's wind-tree model are studied. While in one model normal diffusion occurs, the other model exhibits abnormal diffusion in that the distribution function of the displacements of the wind particle is non-Gaussian, but its second moment, the mean-square displacement, is proportional to the time, so that a diffusion coefficient can be defined. A connection with the percolation problem and a self-avoiding random walk for the case in which the lattice is completely covered with trees is discussed

  12. Soil microbial biomass under different management and tillage systems of permanent intercropped cover species in an orange orchard

    Directory of Open Access Journals (Sweden)

    Elcio Liborio Balota

    2011-12-01

    Full Text Available To mitigate soil erosion and enhance soil fertility in orange plantations, the permanent protection of the inter-rows by cover species has been suggested. The objective of this study was to evaluate alterations in the microbial biomass, due to different soil tillage systems and intercropped cover species between rows of orange trees. The soil of the experimental area previously used as pasture (Brachiaria humidicola was an Ultisol (Typic Paleudult originating from Caiuá sandstone in the northwestern part of the State of Paraná, Brazil. Two soil tillage systems were evaluated: conventional tillage (CT in the entire area and strip tillage (ST (strip width 2 m, in combination with different ground cover management systems. The citrus cultivar 'Pera' orange (Citrus sinensis grafted onto 'Rangpur' lime rootstock was used. Soil samples were collected after five years of treatment from a depth of 0-15 cm, under the tree canopy and in the inter-row, in the following treatments: (1 CT and an annual cover crop with the leguminous species Calopogonium mucunoides; (2 CT and a perennial cover crop with the leguminous peanut Arachis pintoi; (3 CT and an evergreen cover crop with Bahiagrass Paspalum notatum; (4 CT and a cover crop with spontaneous Brachiaria humidicola grass vegetation; and (5 ST and maintenance of the remaining grass (pasture of Brachiaria humidicola. Soil tillage and the different cover species influenced the microbial biomass, both under the tree canopy and in the inter-row. The cultivation of brachiaria increased C and N in the microbial biomass, while bahiagrass increased P in the microbial biomass. The soil microbial biomass was enriched in N and P by the presence of ground cover species and according to the soil P content. The grass species increased C, N and P in the soil microbial biomass from the inter-row more than leguminous species.

  13. Evaluation of Populus and Salix continuously irrigated with landfill leachate II. soils and early tree development.

    Science.gov (United States)

    Zalesny, Ronald S; Bauer, Edmund O

    2007-01-01

    Soil contaminant levels and early tree growth data are helpful for assessing phytoremediation systems. Populus (DN17, DN182, DN34, NM2, and NM6) and Salix (94003, 94012, S287, S566, and SX61) genotypes were irrigated with landfill leachate or municipal water and tested for differences in (1) element concentrations (P, K, Ca, Mg, S, Zn, B, Mn, Fe, Cu, Al, and Na) of a topsoil layer and a layer of sand in tanks with a cover crop of trees or no trees and (2) height, diameter, volume, and dry mass of leaves, stems, and roots. Trees were irrigated with leachate or water during the final 12 wk of the 18-wk study. Differences in most soil element concentrations were negligible (P > 0.05) for irrigation treatments and cover main effects. Phosphorous, K, Mg, S, Zn, Mn, Fe, and Al concentrations were greater in topsoil than sand (P = 0.0011 for Mg; P tree yield. From a practical standpoint, these results may be used as a baseline for the development of future remediation systems.

  14. How to select the best tree planting locations to enhance air pollution removal in the MillionTreesNYC initiative

    International Nuclear Information System (INIS)

    Morani, Arianna; Nowak, David J.; Hirabayashi, Satoshi; Calfapietra, Carlo

    2011-01-01

    Highest priority zones for tree planting within New York City were selected by using a planting priority index developed combining three main indicators: pollution concentration, population density and low canopy cover. This new tree population was projected through time to estimate potential air quality and carbon benefits. Those trees will likely remove more than 10 000 tons of air pollutants and a maximum of 1500 tons of carbon over the next 100 years given a 4% annual mortality rate. Cumulative carbon storage will be reduced through time as carbon loss through tree mortality outweighs carbon accumulation through tree growth. Model projections are strongly affected by mortality rate whose uncertainties limit estimations accuracy. Increasing mortality rate from 4 to 8% per year produce a significant decrease in the total pollution removal over a 100 year period from 11 000 tons to 3000 tons. - Highlights: → The manuscript is part of the IUFRO Special section 'Adaptation of Forest Ecosystems to Air Pollution and Climate Change' (Elena Paoletti and Yusuf Serengil Eds.) approved by William J. Manning. → It has been already peer-reviewed and accepted outside EES. → The reference number of this manuscript is IUFRO49. - Carbon and air pollutant uptake by urban forests are highly influenced by mortality rates.

  15. How to select the best tree planting locations to enhance air pollution removal in the MillionTreesNYC initiative

    Energy Technology Data Exchange (ETDEWEB)

    Morani, Arianna [Institute of Agro-Environmental and Forest Biology (IBAF), National Research Council (CNR) Via Salaria km 29300, 00015 Monterotondo Scalo, Roma (Italy); Nowak, David J.; Hirabayashi, Satoshi [USDA Forest Service, Northern Research Station, 5 Moon Library, SUNY-ESF, Syracuse, NY 13210 (United States); Calfapietra, Carlo, E-mail: carlo.calfapietra@ibaf.cnr.it [Institute of Agro-Environmental and Forest Biology (IBAF), National Research Council (CNR) Via Salaria km 29300, 00015 Monterotondo Scalo, Roma (Italy)

    2011-05-15

    Highest priority zones for tree planting within New York City were selected by using a planting priority index developed combining three main indicators: pollution concentration, population density and low canopy cover. This new tree population was projected through time to estimate potential air quality and carbon benefits. Those trees will likely remove more than 10 000 tons of air pollutants and a maximum of 1500 tons of carbon over the next 100 years given a 4% annual mortality rate. Cumulative carbon storage will be reduced through time as carbon loss through tree mortality outweighs carbon accumulation through tree growth. Model projections are strongly affected by mortality rate whose uncertainties limit estimations accuracy. Increasing mortality rate from 4 to 8% per year produce a significant decrease in the total pollution removal over a 100 year period from 11 000 tons to 3000 tons. - Highlights: > The manuscript is part of the IUFRO Special section 'Adaptation of Forest Ecosystems to Air Pollution and Climate Change' (Elena Paoletti and Yusuf Serengil Eds.) approved by William J. Manning. > It has been already peer-reviewed and accepted outside EES. > The reference number of this manuscript is IUFRO49. - Carbon and air pollutant uptake by urban forests are highly influenced by mortality rates.

  16. Tree resources Of Katerniaghat Wildlife Sanctuary, Uttar Pradesh, India with especial emphasis on conservation status, phenology and economic values

    Directory of Open Access Journals (Sweden)

    Lal Babu Chaudhary

    2014-02-01

    Full Text Available Uttar Pradesh, one of the most populated states of India along international border of Nepal, contributes only about 3% of total forest & tree cover of the country as the major parts of the area is covered by agriculture lands and human populations. The forests are quite fragmented and facing severe anthropogenic pressure in many parts. To protect the existing biodiversity, several forest covers have been declared as National Parks and Wildlife Sanctuaries. In the present study, Katerniaghat Wildlife Sanctuary (KWS has been selected to assess tree diversity, their phenology and economic values as the trees are the major constituent of any forest and more fascinating among all plant groups. The sanctuary consists of tropical moist deciduous type of vegetation and situated along the Indo-Nepal boarder in Bahraich district of Uttar Pradesh, India. After, thorough assessment of the area, a list of 141 tree species belonging to 101 genera and 38 families have been prepared. The family Fabaceae exhibits highest generic and species diversity with 14 genera and 23 species. The genus Ficus of Moraceae has been found the largest with 11 species. Maximum trees with about 51 species have been found to flower in post winter season (February to March in the forest. About 62 trees are used as medicinal for various purposes, 50 as ornamental & avenue trees, 37 as timber wood, 36 as edible, 16 as fire wood and 12 as fodder. Since the sanctuary area has been surrounded by several villages and facing anthropogenic pressure, the public awareness program related with biodiversity conservation and sustainable uses is highly needed to protect the forest covers. DOI: http://dx.doi.org/10.3126/ije.v3i1.9949 International Journal of Environment Vol.3(1 2014: 122-133

  17. Shade factors for 149 taxa of in-leaf urban trees in the USA

    Science.gov (United States)

    E. Gregory McPherson; Qingfu Xiao; Natalie S. van Doorn; Nels Johnson; Shannon Albers; Paula J. Peper

    2018-01-01

    Shade factors, defined as the percentage of sky covered by foliage and branches within the perimeter of individual tree crowns, have been used to model the effects of trees on air pollutant uptake, building energy use and rainfall interception. For the past 30 years the primary source of shade factors was a database containing values from 47 species. In most...

  18. Covering of milled peat stockpile with wood chips; Jyrsinturveauman peittaeminen hakkeella

    Energy Technology Data Exchange (ETDEWEB)

    Franssila, T.; Leinonen, A.

    1996-12-31

    The aim of this project is to research the applicability of wooden materials for protection of milled peat stockpile against losses during storaging. Water transmission features of sawdust, wastewood chip and whole tree chip were investigated in laboratory with raining experiments. The plan for raining experiments was made with experiment planning program and results were analysed with multivariate analysis. Freezing features were investigated thorough breaking tests with hydraulic piston vice. Laboratory experiments were completed with field tests in Laakasuo near Sotkamo. On the basis of results covering peat stockpiles with sawdust is fully competitive comparing to present covering methods. Chip materials are technically not as good covering materials as sawdust

  19. Miombo trees and mycorrhizae : ecological strategies, a basis for afforestation

    NARCIS (Netherlands)

    Munyanziza, E.

    1994-01-01

    This project has covered one or several aspects of the life cycle of the main miombo tree species, namely Afzelia quanzensis ,Brachystegia microphylla, Brachystegia spiciformis

  20. Modelling the effects of climate and land cover change on groundwater recharge in south-west Western Australia

    Directory of Open Access Journals (Sweden)

    W. Dawes

    2012-08-01

    Full Text Available The groundwater resource contained within the sandy aquifers of the Swan Coastal Plain, south-west Western Australia, provides approximately 60 percent of the drinking water for the metropolitan population of Perth. Rainfall decline over the past three decades coupled with increasing water demand from a growing population has resulted in falling dam storage and groundwater levels. Projected future changes in climate across south-west Western Australia consistently show a decline in annual rainfall of between 5 and 15 percent. There is expected to be a reduction of diffuse recharge across the Swan Coastal Plain. This study aims to quantify the change in groundwater recharge in response to a range of future climate and land cover patterns across south-west Western Australia.

    Modelling the impact on the groundwater resource of potential climate change was achieved with a dynamically linked unsaturated/saturated groundwater model. A vertical flux manager was used in the unsaturated zone to estimate groundwater recharge using a variety of simple and complex models based on climate, land cover type (e.g. native trees, plantation, cropping, urban, wetland, soil type, and taking into account the groundwater depth.

    In the area centred on the city of Perth, Western Australia, the patterns of recharge change and groundwater level change are not consistent spatially, or consistently downward. In areas with land-use change, recharge rates have increased. Where rainfall has declined sufficiently, recharge rates are decreasing, and where compensating factors combine, there is little change to recharge. In the southwestern part of the study area, the patterns of groundwater recharge are dictated primarily by soil, geology and land cover. In the sand-dominated areas, there is little response to future climate change, because groundwater levels are shallow and much rainfall is rejected recharge. Where the combination of native vegetation and

  1. Improved Frame Mode Selection for AMR-WB+ Based on Decision Tree

    Science.gov (United States)

    Kim, Jong Kyu; Kim, Nam Soo

    In this letter, we propose a coding mode selection method for the AMR-WB+ audio coder based on a decision tree. In order to reduce computation while maintaining good performance, decision tree classifier is adopted with the closed loop mode selection results as the target classification labels. The size of the decision tree is controlled by pruning, so the proposed method does not increase the memory requirement significantly. Through an evaluation test on a database covering both speech and music materials, the proposed method is found to achieve a much better mode selection accuracy compared with the open loop mode selection module in the AMR-WB+.

  2. Soil microbial communities under cacao agroforestry and cover crop systems in Peru

    Science.gov (United States)

    Cacao (Theobroma cacao) trees are grown in tropical regions worldwide for chocolate production. We studied the effects of agroforestry management systems and cover cropping on soil microbial communities under cacao in two different replicated field experiments in Peru. Two agroforestry systems, Imp...

  3. Understory cover responses to pinon-juniper treatments across tree dominance gradients in the Great Basin

    Science.gov (United States)

    Piñon (Pinus spp.) and juniper (Juniperus spp.) trees are reduced to restore native vegetation and avoid high severity fires where they have invaded sagebrush (Artemisia tridentata Nutt.) communities. To recommend treatment implementation which avoids threshold-crossing to invasive plant dominance w...

  4. Tree Identification. Competency Based Teaching Materials in Horticulture.

    Science.gov (United States)

    Legacy, Jim; And Others

    This competency-based curriculum unit on tree identification is one of five developed for classroom use in teaching the landscape/nursery area of horticulture. The three sections are each divided into teaching content (in a question-and-answer format) and student skills that outline steps and factors for consideration. Topics covered include…

  5. Validation of Land Cover Products Using Reliability Evaluation Methods

    Directory of Open Access Journals (Sweden)

    Wenzhong Shi

    2015-06-01

    Full Text Available Validation of land cover products is a fundamental task prior to data applications. Current validation schemes and methods are, however, suited only for assessing classification accuracy and disregard the reliability of land cover products. The reliability evaluation of land cover products should be undertaken to provide reliable land cover information. In addition, the lack of high-quality reference data often constrains validation and affects the reliability results of land cover products. This study proposes a validation schema to evaluate the reliability of land cover products, including two methods, namely, result reliability evaluation and process reliability evaluation. Result reliability evaluation computes the reliability of land cover products using seven reliability indicators. Process reliability evaluation analyzes the reliability propagation in the data production process to obtain the reliability of land cover products. Fuzzy fault tree analysis is introduced and improved in the reliability analysis of a data production process. Research results show that the proposed reliability evaluation scheme is reasonable and can be applied to validate land cover products. Through the analysis of the seven indicators of result reliability evaluation, more information on land cover can be obtained for strategic decision-making and planning, compared with traditional accuracy assessment methods. Process reliability evaluation without the need for reference data can facilitate the validation and reflect the change trends of reliabilities to some extent.

  6. Best Dressed Test: A Study of the Covering Behavior of the Collector Urchin Tripneustes gratilla.

    Directory of Open Access Journals (Sweden)

    Morgan A Ziegenhorn

    Full Text Available Many sea urchin genera exhibit cryptic covering behaviors. One such behavior has been documented in the sea urchin Tripneustes gratilla, and previous studies have theorized that this behavior serves as protection from UV radiation. However, other hypotheses have been presented such as protection from predators or added weight to help T. gratilla resist strong currents. A field study was conducted in October-November 2015 in Moorea, French Polynesia to assess urchin covering behavior in natural habitats. The study found that urchins partially underneath rocks covered more, and with more algae, than urchins totally underneath rocks. To test if this behavior was driven by light intensity, a series of 30-minute experimental trials were run on 10 individuals in bright and dim conditions. Individuals were given red and clear plastic, and percent cover of each was recorded. These tests were repeated once fifty percent of spines had been removed from the urchin, in order to determine whether spine loss affects T. gratilla covering behavior. The study found that urchins had a distinct preference for cover that best protects them from UV radiation. Spine loss did not significantly affect urchin ability to cover, and urchins with removed spines still preferred opaque cover. Additionally, covering behavior was mapped onto a phylogeny of echinoderms to determine how it might have evolved. Understanding urchin covering behavior more fully is a step towards an understanding of the evolution of cryptic behavior across species.

  7. Denmark; Systemic Issues in Mortgage Loans and Covered Bond Finance: Technical Note

    OpenAIRE

    International Monetary Fund

    2014-01-01

    This technical note analyzes systemic issues in mortgage loans and covered bond finance in Denmark. Mortgage lending has seen significant product innovation in recent years. Loans with adjustable interest rates and/or interest-only periods, which have been introduced since the late 1990s, had grown to 75 percent and 53 percent, respectively, of total outstanding mortgage loans at the end of 2013. The major changes in the characteristics of the underlying mortgage loans have naturally been ref...

  8. Fire frequency and tree canopy structure influence plant species diversity in a forest-grassland ecotone

    Science.gov (United States)

    David W. Peterson; Peter B. Reich

    2008-01-01

    Disturbances and environmental heterogeneity are two factors thought to influence plant species diversity, but their effects are still poorly understood in many ecosystems. We surveyed understory vegetation and measured tree canopy cover on permanent plots spanning an experimental fire frequency gradient to test fire frequency and tree canopy effects on plant species...

  9. 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...

  10. Site specific management in an olive tree plantation

    DEFF Research Database (Denmark)

    Fountas, S.; Aggelopoulou, K.; Bouloulis, C.

    2011-01-01

    Yield and soil mapping were carried out in 2007 and 2008 in a 9.1 ha commercial olive tree plantation for olive oil production. The orchard is in the southern Peloponnese, where olives are cultivated extensively for extra virgin olive oil production. The field is planted in rows with about 1650...... shoots and letting the olives fall onto a plastic net covering the ground. Sacks of approximately 58 kg capacity were filled with olives from as many adjacent trees as were needed to fill a sack. The location of the sacks, or group of closely placed sacks, was identified using a commercial GPS (5 m...

  11. Transfer of radiocesium in the fruit tree

    International Nuclear Information System (INIS)

    Takata, Daisuke

    2013-01-01

    After Fukushima Nuclear Power Plant Accident (Mar. 2011), the author has investigated the transfer of radiocesium (rCs) mainly in peach trees under the actual and cultivating conditions in Fukushima and Tokyo areas, of which results are given with their discussion herein. There are 2 routes of the transfer through the root absorbing the soil rCs originally fallen on the ground and through the aboveground organs absorbing the directly attached rCs on them. The latter attachment includes one on the old branch and main stem existed before the Accident, and another, on the leaf, young shoot and fruit (pericarp) absent at the Accident. Experimental data of peach tree with/without a ground cover show that in the year of the Accident (2011), rCs transfer in the tree body through the aboveground organs was superior to that through the root, and this was also confirmed in the grape tree. Analysis with the imaging plate revealed that a quite high level of rCs was present in the outer thin layer of the bark and in the lenticel, which was conceived to be the possible route of transfer in the tree body. rCs levels on fresh organs like pericarp were lowered by rinsing, suggesting that the nuclide was movable on the old organs to be transferred in new ones. When the tree grown at the high dose area was dug up for its root to be rinsed and partly cut and then the tree was cultivated in non-contaminated soil, the newly shot root contained the higher level of rCs than the leaf, of which mechanism is under investigation. rCs transfer in the tree from the soil and space, and reverse distribution possibly occur: the both sides are to be further investigated qualitatively and quantitatively. (T.T.)

  12. Tree rings and radiocarbon calibration

    International Nuclear Information System (INIS)

    Barbetti, M.

    1999-01-01

    Only a few kinds of trees in Australia and Southeast Asia are known to have growth rings that are both distinct and annual. Those that do are therefore extremely important to climatic and isotope studies. In western Tasmania, extensive work with Huon pine (Lagarostrobos franklinii) has shown that many living trees are more than 1,000 years old, and that their ring widths are sensitive to temperature, rainfall and cloud cover (Buckley et al. 1997). At the Stanley River there is a forest of living (and recently felled) trees which we have sampled and measured. There are also thousands of subfossil Huon pine logs, buried at depths less than 5 metres in an area of floodplain extending over a distance of more than a kilometre with a width of tens of metres. Some of these logs have been buried for 50,000 years or more, but most of them belong to the period between 15,000 years and the present. In previous expeditions in the 1980s and 1990s, we excavated and sampled about 350 logs (Barbetti et al. 1995; Nanson et al. 1995). By measuring the ring-width patterns, and matching them between logs and living trees, we have constructed a tree-ring dated chronology from 571 BC to AD 1992. We have also built a 4254-ring floating chronology (placed by radiocarbon at ca. 3580 to 7830 years ago), and an earlier 1268-ring chronology (ca. 7,580 to 8,850 years ago). There are many individuals, or pairs of logs which match and together span several centuries, at 9,000 years ago and beyond

  13. Treatment of complementary events in event trees in constructing linked fault trees for level 1 and level 2 PRA

    International Nuclear Information System (INIS)

    Jo, Y. G.

    2008-01-01

    Complementary events in the event trees for a PRA model should be treated properly in order to evaluate plant risk correctly. In this study, the characteristics of the following three different cut-set generation methods were investigated first in order to find the best practical way for treating complementary events: 1) exact method which treats complementary events logically, 2) no-delete term method which does not treat complementary events at all, and 3) delete term method which treats complementary events by deleting nonsense cut-sets which are generated as a result of ignoring complementary events. Then, practical methods for treating complementary events in constructing linked fault trees for level 1 and level 2 PRA in EPRI R and R workstation software environment, where CAFTA is the fault tree editor and FORTE is the cut-set engine, were suggested and demonstrated. The suggested methods deal with the following selected four typical cases: Case 1: an event tree event (E) is represented by a fault tree gate whose inputs consist of only fault tree gates, Case 2: E is represented by a single basic event, Case 3: E is represented by an OR fault tree gate which has a single basic event and a fault tree gate as inputs, and Case 4: E is represented by an AND fault tree gate which has a single basic event and a fault tree gate as inputs. In the suggested methods, first the high level logic structures of event tree events are examined and restructured, if needed. Then, the delete term method, the exact method, and the combination of the two methods are applied to Case 1, Case 2, and Cases 3 and 4, respectively. Also, it is recommended to treat complementary events, using the suggested methods, before level 1 and level 2 PRA fault trees are coupled. It should be noted that the selected four typical cases may not cover all different cases encountered in level 1 and level 2 PRA modeling. However, a process similar to the one suggested in this study may be used to find

  14. Trees and Streets as Drivers of Urban Stormwater Nutrient Pollution.

    Science.gov (United States)

    Janke, Benjamin D; Finlay, Jacques C; Hobbie, Sarah E

    2017-09-05

    Expansion of tree cover is a major management goal in cities because of the substantial benefits provided to people, and potentially to water quality through reduction of stormwater volume by interception. However, few studies have addressed the full range of potential impacts of trees on urban runoff, which includes deposition of nutrient-rich leaf litter onto streets connected to storm drains. We analyzed the influence of trees on stormwater nitrogen and phosphorus export across 19 urban watersheds in Minneapolis-St. Paul, MN, U.S.A., and at the scale of individual streets within one residential watershed. Stormwater nutrient concentrations were highly variable across watersheds and strongly related to tree canopy over streets, especially for phosphorus. Stormwater nutrient loads were primarily related to road density, the dominant control over runoff volume. Street canopy exerted opposing effects on loading, where elevated nutrient concentrations from trees near roads outweighed the weak influence of trees on runoff reduction. These results demonstrate that vegetation near streets contributes substantially to stormwater nutrient pollution, and therefore to eutrophication of urban surface waters. Urban landscape design and management that account for trees as nutrient pollution sources could improve water quality outcomes, while allowing cities to enjoy the myriad benefits of urban forests.

  15. i-Tree: Tools to assess and manage structure, function, and value of community forests

    Science.gov (United States)

    Hirabayashi, S.; Nowak, D.; Endreny, T. A.; Kroll, C.; Maco, S.

    2011-12-01

    Trees in urban communities can mitigate many adverse effects associated with anthropogenic activities and climate change (e.g. urban heat island, greenhouse gas, air pollution, and floods). To protect environmental and human health, managers need to make informed decisions regarding urban forest management practices. Here we present the i-Tree suite of software tools (www.itreetools.org) developed by the USDA Forest Service and their cooperators. This software suite can help urban forest managers assess and manage the structure, function, and value of urban tree populations regardless of community size or technical capacity. i-Tree is a state-of-the-art, peer-reviewed Windows GUI- or Web-based software that is freely available, supported, and continuously refined by the USDA Forest Service and their cooperators. Two major features of i-Tree are 1) to analyze current canopy structures and identify potential planting spots, and 2) to estimate the environmental benefits provided by the trees, such as carbon storage and sequestration, energy conservation, air pollution removal, and storm water reduction. To cover diverse forest topologies, various tools were developed within the i-Tree suite: i-Tree Design for points (individual trees), i-Tree Streets for lines (street trees), and i-Tree Eco, Vue, and Canopy (in the order of complexity) for areas (community trees). Once the forest structure is identified with these tools, ecosystem services provided by trees can be estimated with common models and protocols, and reports in the form of texts, charts, and figures are then created for users. Since i-Tree was developed with a client/server architecture, nationwide data in the US such as location-related parameters, weather, streamflow, and air pollution data are stored in the server and retrieved to a user's computer at run-time. Freely available remote-sensed images (e.g. NLCD and Google maps) are also employed to estimate tree canopy characteristics. As the demand for i-Tree

  16. Detecting tree-like multicellular life on extrasolar planets.

    Science.gov (United States)

    Doughty, Christopher E; Wolf, Adam

    2010-11-01

    Over the next two decades, NASA and ESA are planning a series of space-based observatories to find Earth-like planets and determine whether life exists on these planets. Previous studies have assessed the likelihood of detecting life through signs of biogenic gases in the atmosphere or a red edge. Biogenic gases and the red edge could be signs of either single-celled or multicellular life. In this study, we propose a technique with which to determine whether tree-like multicellular life exists on extrasolar planets. For multicellular photosynthetic organisms on Earth, competition for light and the need to transport water and nutrients has led to a tree-like body plan characterized by hierarchical branching networks. This design results in a distinct bidirectional reflectance distribution function (BRDF) that causes differing reflectance at different sun/view geometries. BRDF arises from the changing visibility of the shadows cast by objects, and the presence of tree-like structures is clearly distinguishable from flat ground with the same reflectance spectrum. We examined whether the BRDF could detect the existence of tree-like structures on an extrasolar planet by using changes in planetary albedo as a planet orbits its star. We used a semi-empirical BRDF model to simulate vegetation reflectance at different planetary phase angles and both simulated and real cloud cover to calculate disk and rotation-averaged planetary albedo for a vegetated and non-vegetated planet with abundant liquid water. We found that even if the entire planetary albedo were rendered to a single pixel, the rate of increase of albedo as a planet approaches full illumination would be comparatively greater on a vegetated planet than on a non-vegetated planet. Depending on how accurately planetary cloud cover can be resolved and the capabilities of the coronagraph to resolve exoplanets, this technique could theoretically detect tree-like multicellular life on exoplanets in 50 stellar systems.

  17. Post-fire salvage logging alters species composition and reduces cover, richness, and diversity in Mediterranean plant communities.

    Science.gov (United States)

    Leverkus, Alexandro B; Lorite, Juan; Navarro, Francisco B; Sánchez-Cañete, Enrique P; Castro, Jorge

    2014-01-15

    An intense debate exists on the effects of post-fire salvage logging on plant community regeneration, but scant data are available derived from experimental studies. We analyzed the effects of salvage logging on plant community regeneration in terms of species richness, diversity, cover, and composition by experimentally managing a burnt forest on a Mediterranean mountain (Sierra Nevada, S Spain). In each of three plots located at different elevations, three replicates of three treatments were implemented seven months after the fire, differing in the degree of intervention: "Non-Intervention" (all trees left standing), "Partial Cut plus Lopping" (felling 90% of the trees, cutting the main branches, and leaving all the biomass in situ), and "Salvage Logging" (felling and piling the logs, and masticating the woody debris). Plant composition in each treatment was monitored two years after the fire in linear point transects. Post-fire salvage logging was associated with reduced species richness, Shannon diversity, and total plant cover. Moreover, salvaged sites hosted different species assemblages and 25% lower cover of seeder species (but equal cover of resprouters) compared to the other treatments. Cover of trees and shrubs was also lowest in Salvage Logging, which could suggest a potential slow-down of forest regeneration. Most of these results were consistent among the three plots despite plots hosting different plant communities. Concluding, our study suggests that salvage logging may reduce species richness and diversity, as well as the recruitment of woody species, which could delay the natural regeneration of the ecosystem. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. A Conceptual Model for Solving Percent Problems.

    Science.gov (United States)

    Bennett, Albert B., Jr.; Nelson, L. Ted

    1994-01-01

    Presents an alternative method to teaching percent problems which uses a 10x10 grid to help students visualize percents. Offers a means of representing information and suggests different approaches for finding solutions. Includes reproducible student worksheet. (MKR)

  19. The Algebra of the Cumulative Percent Operation.

    Science.gov (United States)

    Berry, Andrew J.

    2002-01-01

    Discusses how to help students avoid some pervasive reasoning errors in solving cumulative percent problems. Discusses the meaning of ."%+b%." the additive inverse of ."%." and other useful applications. Emphasizes the operational aspect of the cumulative percent concept. (KHR)

  20. Using Unmanned Aerial Vehicles to Assess Vegetative Cover and Identify Biotic Resources in Sagebrush Steppe Ecosystems: Preliminary Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Robert P. Breckenridge

    2006-04-01

    The Idaho National Laboratory (INL), in conjunction with the University of Idaho, is evaluating novel approaches for using unmanned aerial vehicles (UAVs) as a quicker and safer method for monitoring biotic resources. Evaluating vegetative cover is an important factor in understanding the sustainability of many ecosystems. In assessing vegetative cover, methods that improve accuracy and cost efficiency could revolutionize how biotic resources are monitored on western federal lands. Sagebrush steppe ecosystems provide important habitat for a variety of species, some of which are important indicator species (e.g., sage grouse). Improved methods are needed to support monitoring these habitats because there are not enough resource specialists or funds available for comprehensive ground evaluation of these ecosystems. In this project, two types of UAV platforms (fixed wing and helicopter) were used to collect still-frame imagery to assess cover in sagebrush steppe ecosystems. This paper discusses the process for collecting and analyzing imagery from the UAVs to (1) estimate total percent cover, (2) estimate percent cover for six different types of vegetation, and (3) locate sage grouse based on representative decoys. The field plots were located on the INL site west of Idaho Falls, Idaho, in areas with varying amounts and types of vegetative cover. A software program called SamplePoint developed by the U.S. Department of Agriculture, Agricultural Research Service was used to evaluate the imagery for percent cover for the six vegetation types (bare ground, litter, shrubs, dead shrubs, grasses, and forbs). Results were compared against standard field measurements to assess accuracy.

  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. Recent Relationships of Tree Establishment and Climate in Alpine Treelines of the Rocky Mountains

    Science.gov (United States)

    Germino, M. J.; Graumlich, L. J.; Maher, E. J.

    2007-12-01

    Changes in the forest structure of alpine-forest or treeline boundaries may be a significant climate response of mountainous regions in the near future. A particularly important point of climate sensitivity for treelines is the initial survival and establishment of tree seedlings - a demographic bottleneck that may be particularly suited to early detection of treeline responses to climate change. However, concise information on climate sensitivity of seedling establishment has come primarily from direct observations of seedlings over short time periods encompassing a few years. Dendrochronological approaches have revealed tree establishment patterns at more extensive time scales of decades to millenia, but at coarser temporal resolutions. Climate variations that most directly affect initial tree seedling establishment occur at annual or smaller time scales, and climate for seedlings is modulated by landscape factors such as neighboring plant cover. Our objective was to assess climate sensitivity of tree establishment at treeline at these finer temporal and spatial scales, with consideration of treeline features that alter the climate for seedlings. Our approach combined direct observations of seedling emergence and survival with dendrochronology of older seedlings and saplings that were still small and young enough (less than 25 years and 20 cm height) to allow detecting the year of establishment and associated factors. Surveys for subject seedlings and saplings were performed for 2 years across the gradient from forest into treeline alpine in the Beartooth, Teton, and Medicine Bow mountains of Wyoming USA. No seedlings or saplings were detected above the highest elevation adult trees or krummholz, but there were up to 0.3 seedlings per square meter in subalpine meadows close to forest (within the timberline zone) where changes in tree abundance appear possible in future decades. Correlations of establishment and summer temperature ranged from weak in whitebark

  3. Diameter Growth of Loblolly Pine Trees as Affected by Soil-Moisture Availibility

    Science.gov (United States)

    John R. Bassett

    1964-01-01

    In a 30-year-old even-aged stand of loblolly pine on a site 90 loessial soil in southeast Arkansas during foul growing seasons, most trees on plots thinned to 125 square feet of basal area per acre increased in basal area continuously when, under the crown canopy, available water in the surface foot remained above 65 percent. Measurable diameter growth ceased when...

  4. Farmers' contributions to the conservation of tree diversity in the Groundnut Basin, Senegal

    Institute of Scientific and Technical Information of China (English)

    Antoine Sambou; Bienvenu Sambou; Anders R(ae)bild

    2017-01-01

    Tree diversity in West Africa is threatened by intensified land uses and salinization,and farmers' role in conservation of tree species is unclear.We hypothesized that farmers contribute to conservation of tree diversity through protection of trees in their agroforestry landscapes and compared the diversity and structure of the tree vegetation across landscape classes.Inventories were carried out in three villages in the Groundnut Basin in Senegal,assessing tree diversity,density and crown cover.Tree diversity as assessed by species accumulation curves was high in forests,but cultivated landscapes had comparable or almost comparable diversity,especially in the cases where the forest was planted or was affected by charcoal production.However,the occurrence of exotic species was higher in cultivated parts of the landscape,and although many species were in common,ordination plots indicated that forests and cultivated landscapes to some degree had different species composition.Salinity had a strong influence on vegetation,not only in the tans (salt marshes) but also across the other landscape classes.In conclusion,agroforestry landscapes in the three villages harbor considerable tree diversity,but insufficient to fully conserve the tree species.We argue that informing and including farmers in tree management in the region will contribute to overall conservation of tree genetic resources.

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

    Science.gov (United States)

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

    2017-12-01

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

  6. Should we plant trees to offset greenhouse gas emissions in semi-arid environments?

    Science.gov (United States)

    Pataki, D. E.; Pincetl, S.; Gillespie, T. W.; Li, W.; McCarthy, H. R.; Saatchi, S.; Saphores, J.

    2008-12-01

    Urban tree planting programs have been gaining popularity in the United States. Urban trees have been associated with a variety of environmental benefits, including improvements in air quality, mitigation of urban heat island effects, reductions in stormwater runoff, and more recently, carbon sequestration. There are also other potential aesthetic and economic benefits of urban forests, which have been shown to affect real estate values. However, there may also be significant economic and environmental costs of planting and maintaining trees in urban areas, particularly in semi-arid environments where trees are not native and require irrigation and fertilization. We are conducting an analysis of the Million Tree Initiative in the city of Los Angeles, which has committed to a major tree planting program. Los Angeles currently has a low tree canopy cover relative to other cities, particularly in its low income neighborhoods. We are evaluating the decision-making processes associated with the new tree planting program, its perceived benefits, and its actual benefits based on measurements of plant and ecosystem processes such as transpiration, photosynthesis, and water use efficiency; remote sensing analyses of tree cover and surface temperature; and economic analyses. We have found great variability in the interpretation of the program by its various participants, but also significant institutional learning as the program has evolved. Our datasets have challenged some of the common assumptions of the program, for example, the assumption that native species use less water than imported species and are therefore more environmentally beneficial in terms of water resources. We have also found significant impacts of the urban forest on air temperature, which may reduce energy use during the summer due to reductions in air conditioning. This is likely to be a larger effect of urban trees on greenhouse gas emissions than direct carbon sequestration alone, which is a very

  7. Fuel buildup and potential fire behavior after stand-replacing fires, logging fire-killed trees and herbicide shrub removal in Sierra Nevada forests

    Science.gov (United States)

    McGinnis, Thomas W.; Keeley, Jon E.; Stephens, Scott L.; Roller, Gary B.

    2010-01-01

    Typically, after large stand-replacing fires in mid-elevation Sierra Nevada forests, dense shrub fields occupy sites formerly occupied by mature conifers, until eventually conifers overtop and shade out shrubs. Attempting to reduce fuel loads and expedite forest regeneration in these areas, the USDA Forest Service often disrupts this cycle by the logging of fire-killed trees, replanting of conifers and killing of shrubs. We measured the effects of these treatments on live and dead fuel loads and alien species and modeled potential fire behavior and fire effects on regenerating forests. Sampling occurred in untreated, logged and herbicide-treated stands throughout the Sierra Nevada in four large fire areas 4–21 years after stand-replacing fires. Logging fire-killed trees significantly increased total available dead fuel loads in the short term but did not affect shrub cover, grass and forb cover, alien species cover or alien species richness. Despite the greater available dead fuel loads, fire behavior was not modeled to be different between logged and untreated stands, due to abundant shrub fuels in both logged and untreated stands. In contrast, the herbicide treatment directed at shrubs resulted in extremely low shrub cover, significantly greater alien species richness and significantly greater alien grass and forb cover. Grass and forb cover was strongly correlated with solar radiation on the ground, which may be the primary reason that grass and forb cover was higher in herbicide treated stands with low shrub and tree cover. Repeat burning exacerbated the alien grass problem in some stands. Although modeled surface fire flame lengths and rates of spread were found to be greater in stands dominated by shrubs, compared to low shrub cover conifer plantations, surface fire would still be intense enough to kill most trees, given their small size and low crown heights in the first two decades after planting.

  8. Tree compression with top trees

    DEFF Research Database (Denmark)

    Bille, Philip; Gørtz, Inge Li; Landau, Gad M.

    2013-01-01

    We introduce a new compression scheme for labeled trees based on top trees [3]. Our compression scheme is the first to simultaneously take advantage of internal repeats in the tree (as opposed to the classical DAG compression that only exploits rooted subtree repeats) while also supporting fast...

  9. Tree compression with top trees

    DEFF Research Database (Denmark)

    Bille, Philip; Gørtz, Inge Li; Landau, Gad M.

    2015-01-01

    We introduce a new compression scheme for labeled trees based on top trees. Our compression scheme is the first to simultaneously take advantage of internal repeats in the tree (as opposed to the classical DAG compression that only exploits rooted subtree repeats) while also supporting fast...

  10. Accounting for density reduction and structural loss in standing dead trees: Implications for forest biomass and carbon stock estimates in the United States

    Directory of Open Access Journals (Sweden)

    Domke Grant M

    2011-11-01

    Full Text Available Abstract Background Standing dead trees are one component of forest ecosystem dead wood carbon (C pools, whose national stock is estimated by the U.S. as required by the United Nations Framework Convention on Climate Change. Historically, standing dead tree C has been estimated as a function of live tree growing stock volume in the U.S.'s National Greenhouse Gas Inventory. Initiated in 1998, the USDA Forest Service's Forest Inventory and Analysis program (responsible for compiling the Nation's forest C estimates began consistent nationwide sampling of standing dead trees, which may now supplant previous purely model-based approaches to standing dead biomass and C stock estimation. A substantial hurdle to estimating standing dead tree biomass and C attributes is that traditional estimation procedures are based on merchantability paradigms that may not reflect density reductions or structural loss due to decomposition common in standing dead trees. The goal of this study was to incorporate standing dead tree adjustments into the current estimation procedures and assess how biomass and C stocks change at multiple spatial scales. Results Accounting for decay and structural loss in standing dead trees significantly decreased tree- and plot-level C stock estimates (and subsequent C stocks by decay class and tree component. At a regional scale, incorporating adjustment factors decreased standing dead quaking aspen biomass estimates by almost 50 percent in the Lake States and Douglas-fir estimates by more than 36 percent in the Pacific Northwest. Conclusions Substantial overestimates of standing dead tree biomass and C stocks occur when one does not account for density reductions or structural loss. Forest inventory estimation procedures that are descended from merchantability standards may need to be revised toward a more holistic approach to determining standing dead tree biomass and C attributes (i.e., attributes of tree biomass outside of sawlog

  11. Reversing a tree regeneration crisis in an endangered ecoregion.

    Science.gov (United States)

    Fischer, Joern; Stott, Jenny; Zerger, Andre; Warren, Garth; Sherren, Kate; Forrester, Robert I

    2009-06-23

    Global food demand is growing rapidly. Livestock grazing can provide a valuable source of protein, but conventional grazing is often unsustainable. We studied an 800,000-ha section of a threatened ecoregion in southeastern Australia. Conventional management in the region involves continuous livestock grazing with few rest periods and regular fertilizer application. By using remotely sensed data on tree cover and extensive field data on livestock grazing regimes, soil chemistry, tree diameters, and tree regeneration, we show that the region is facing a tree regeneration crisis. Under conventional management, across the region, millions of hectares of land currently supporting tens of millions of trees will be treeless within decades from now. This would have severe negative ramifications for biodiversity and key ecosystem services, including water infiltration and shade provision for livestock. However, we identified an unexpected win-win solution for tree regeneration and commercial grazing. A relatively new practice in the region is fast-rotational grazing, characterized by prolonged rest periods in between short, intensive grazing events. The probability of regeneration under fast-rotational grazing was up to 4-fold higher than under conventional grazing, and it did not differ significantly from the probability of regeneration in ungrazed areas. In addition, trees were more likely to regenerate where soil nutrient levels were low. These findings suggest that the tree regeneration crisis can be reversed by applying low-input, fast-rotational grazing. New policy settings supporting these practices could signal a turning point for the region, from ecological decline to ecological recovery.

  12. Delineating Individual Trees from Lidar Data: A Comparison of Vector- and Raster-based Segmentation Approaches

    Directory of Open Access Journals (Sweden)

    Maggi Kelly

    2013-08-01

    Full Text Available Light detection and ranging (lidar data is increasingly being used for ecosystem monitoring across geographic scales. This work concentrates on delineating individual trees in topographically-complex, mixed conifer forest across the California’s Sierra Nevada. We delineated individual trees using vector data and a 3D lidar point cloud segmentation algorithm, and using raster data with an object-based image analysis (OBIA of a canopy height model (CHM. The two approaches are compared to each other and to ground reference data. We used high density (9 pulses/m2, discreet lidar data and WorldView-2 imagery to delineate individual trees, and to classify them by species or species types. We also identified a new method to correct artifacts in a high-resolution CHM. Our main focus was to determine the difference between the two types of approaches and to identify the one that produces more realistic results. We compared the delineations via tree detection, tree heights, and the shape of the generated polygons. The tree height agreement was high between the two approaches and the ground data (r2: 0.93–0.96. Tree detection rates increased for more dominant trees (8–100 percent. The two approaches delineated tree boundaries that differed in shape: the lidar-approach produced fewer, more complex, and larger polygons that more closely resembled real forest structure.

  13. Lichens of fruit trees in the selected locations in Podlaskie Voivodeship [North-Eastern Poland

    Directory of Open Access Journals (Sweden)

    Matwiejuk Anna

    2017-12-01

    Full Text Available The aim of this paper is to present the diversity of the lichen species on fruit trees (Malus sp., Pyrus sp., Prunus sp. and Cerasus sp. growing in orchards in selected villages and towns in the Podlaskie Voivodeship. Fifty-six species of lichens were found. These were dominated by common lichens found on the bark of trees growing in built-up areas with prevailing heliophilous and nitrophilous species of the genera Physcia and Phaeophyscia. A richer lichen biota is characteristic of apple trees (52 species and pear trees (36. Lichens of the apple trees constitute 78% of the biota of this phorophyte growing in the fruit orchards in Poland. Of the recorded species, only two (Ramalina farinacea, Usnea hirta are covered by partial protection in Poland.

  14. Incorporating Canopy Cover for Airborne-Derived Assessments of Forest Biomass in the Tropical Forests of Cambodia.

    Science.gov (United States)

    Singh, Minerva; Evans, Damian; Coomes, David A; Friess, Daniel A; Suy Tan, Boun; Samean Nin, Chan

    2016-01-01

    This research examines the role of canopy cover in influencing above ground biomass (AGB) dynamics of an open canopied forest and evaluates the efficacy of individual-based and plot-scale height metrics in predicting AGB variation in the tropical forests of Angkor Thom, Cambodia. The AGB was modeled by including canopy cover from aerial imagery alongside with the two different canopy vertical height metrics derived from LiDAR; the plot average of maximum tree height (Max_CH) of individual trees, and the top of the canopy height (TCH). Two different statistical approaches, log-log ordinary least squares (OLS) and support vector regression (SVR), were used to model AGB variation in the study area. Ten different AGB models were developed using different combinations of airborne predictor variables. It was discovered that the inclusion of canopy cover estimates considerably improved the performance of AGB models for our study area. The most robust model was log-log OLS model comprising of canopy cover only (r = 0.87; RMSE = 42.8 Mg/ha). Other models that approximated field AGB closely included both Max_CH and canopy cover (r = 0.86, RMSE = 44.2 Mg/ha for SVR; and, r = 0.84, RMSE = 47.7 Mg/ha for log-log OLS). Hence, canopy cover should be included when modeling the AGB of open-canopied tropical forests.

  15. Spatial distribution of block falls using volumetric GIS-decision-tree models

    Science.gov (United States)

    Abdallah, C.

    2010-10-01

    Block falls are considered a significant aspect of surficial instability contributing to losses in land and socio-economic aspects through their damaging effects to natural and human environments. This paper predicts and maps the geographic distribution and volumes of block falls in central Lebanon using remote sensing, geographic information systems (GIS) and decision-tree modeling (un-pruned and pruned trees). Eleven terrain parameters (lithology, proximity to fault line, karst type, soil type, distance to drainage line, elevation, slope gradient, slope aspect, slope curvature, land cover/use, and proximity to roads) were generated to statistically explain the occurrence of block falls. The latter were discriminated using SPOT4 satellite imageries, and their dimensions were determined during field surveys. The un-pruned tree model based on all considered parameters explained 86% of the variability in field block fall measurements. Once pruned, it classifies 50% in block falls' volumes by selecting just four parameters (lithology, slope gradient, soil type, and land cover/use). Both tree models (un-pruned and pruned) were converted to quantitative 1:50,000 block falls' maps with different classes; starting from Nil (no block falls) to more than 4000 m 3. These maps are fairly matching with coincidence value equal to 45%; however, both can be used to prioritize the choice of specific zones for further measurement and modeling, as well as for land-use management. The proposed tree models are relatively simple, and may also be applied to other areas (i.e. the choice of un-pruned or pruned model is related to the availability of terrain parameters in a given area).

  16. Generalising tree traversals and tree transformations to DAGs

    DEFF Research Database (Denmark)

    Bahr, Patrick; Axelsson, Emil

    2017-01-01

    We present a recursion scheme based on attribute grammars that can be transparently applied to trees and acyclic graphs. Our recursion scheme allows the programmer to implement a tree traversal or a tree transformation and then apply it to compact graph representations of trees instead. The resul......We present a recursion scheme based on attribute grammars that can be transparently applied to trees and acyclic graphs. Our recursion scheme allows the programmer to implement a tree traversal or a tree transformation and then apply it to compact graph representations of trees instead...... as the complementing theory with a number of examples....

  17. The tree-felling campaign has to continue

    CERN Multimedia

    2013-01-01

    The tree-felling campaign that began in 2010 continued last winter, as we reported in our article of 4 March 2013 (see here). While safety concerns* are the main driver, the campaign will also allow a coherent landscaping plan to be implemented.   The areas where trees have already been felled are currently being redesigned, and replanting is scheduled to begin in 2014. CERN has initiated a study in collaboration with the Geneva nature and countryside directorate (Direction générale de la nature et du paysage, DGNP) with a view to drawing up a master plan covering all the green spaces on the Meyrin site. The aim of the study is to understand the landscaping issues at stake and to define a comprehensive redevelopment and landscaping programme for the whole site. In this framework, the areas where trees have been cut down since 2010 will be replanted. The study will also allow CERN to identify the areas that need to be redeveloped as a priority and to establish how this can be ...

  18. Estimating cavity tree and snag abundance using negative binomial regression models and nearest neighbor imputation methods

    Science.gov (United States)

    Bianca N.I. Eskelson; Hailemariam Temesgen; Tara M. Barrett

    2009-01-01

    Cavity tree and snag abundance data are highly variable and contain many zero observations. We predict cavity tree and snag abundance from variables that are readily available from forest cover maps or remotely sensed data using negative binomial (NB), zero-inflated NB, and zero-altered NB (ZANB) regression models as well as nearest neighbor (NN) imputation methods....

  19. Effects of rooting and tree growth of selected woodland species on cap integrity in a mineral capped landfill site.

    Science.gov (United States)

    Hutchings, T R; Moffat, A J; Kemp, R A

    2001-06-01

    The above and below ground growth of three tree species (Alnus glutinosa, Pinus nigra var. maritima and Acer pseudoplatanus) was studied on a containment landfill site at Waterford, Hertfordshire, UK. Tree root architecture was studied using soil inspection pits excavated next to 12 trees of each species and mapped in detail. Tree height was related to soil thickness over the compacted mineral cap. No roots entered the cap where soil thickness was 1.3 m, but a few roots, especially of alder, were observed within it when the soil cover was 1.0 m or less. Micromorphological analysis of undisturbed samples of the mineral cap suggested that roots exploited weaknesses in the cap rather than actively causing penetration into it. Alder roots were more tolerant of anaerobic conditions within the cap than the other species examined. The results confirm that mineral caps should be covered by 1.5 m of soil or soil-forming material if tree establishment is intended over a restored landfill site, unless protected by other parts of a composite capping system.

  20. Determination of percent calcium carbonate in calcium chromate

    International Nuclear Information System (INIS)

    Middleton, H.W.

    1979-01-01

    The precision, accuracy and reliability of the macro-combustion method is superior to the Knorr alkalimetric method, and it is faster. It also significantly reduces the calcium chromate waste accrual problem. The macro-combustion method has been adopted as the official method for determination of percent calcium carbonate in thermal battery grade anhydrous calcium chromate and percent calcium carbonate in quicklime used in the production of calcium chromate. The apparatus and procedure can be used to measure the percent carbonate in inorganic materials other than calcium chromate. With simple modifications in the basic apparatus and procedure, the percent carbon and hydrogen can be measured in many organic material, including polymers and polymeric formulations. 5 figures, 5 tables

  1. Potential Nitrification and Nitrogen Mineral of Soil in Coffee Agroforestry System with Various Shading Trees

    Directory of Open Access Journals (Sweden)

    Purwanto .

    2007-05-01

    Full Text Available The role of shading trees in coffee farms has been well understood to establish suitable condition for the growth of coffee trees, on the other hand their role in nitrogen cycle in coffee farming is not yet well understood. The objectives of this study are to investigate the influence of various legume shading trees on the concentration of soil mineral N (N-NH4 + and N-NO3-, potential nitrification and to study the controlling factors of nitrification under field conditions. This field explorative research was carried out in Sumberjaya, West Lampung. Twelve observation plots covered four land use systems (LUS, i.e. 1 Coffee agroforestry with Gliricidiasepium as shade trees; 2 Coffee agroforestry with Gliricidiaas shade trees and Arachis pintoias cover crops; 3Coffee agroforestry with Paraserianthes falcataria as shade trees; and 4 Mixed/multistrata coffee agroforestry with Gliricidiaand other fruit crops as shade trees. Measurements of soil mineral-N concentration were carried out every three weeks for three months. Results showed that shade tree species in coffee agroforestry significantly affected concentrations of soil NH4 +, NO3- and potential nitrification. Mixed coffee agroforestry had the highest NH4+/N-mineral ratio (7.16% and the lowest potential nitrification (0.13 mg NO2-kg-1 hour -1 compared to other coffee agroforestry systems using single species of leguminous shade trees. Ratio of NH4 + /N-mineral increased 0.8—21% while potential nitrification decreased 55—79% in mixed coffee agroforestry compared to coffee agroforestry with Gliricidia or P. falcatariaas shade trees. Coffee agroforestry with P. falcatariaas shade trees had potential nitrification 53% lower and ratio of NH4 + /N-mineral concentration 20% higher than that with Gliricidia. Coffee agroforestry with P. falcataria as shade trees also had organic C content 17% higher, total N 40% higher, available P 112% higher than that with Gliricidia. The presence of A. pintoiin

  2. Surface tree languages and parallel derivation trees

    NARCIS (Netherlands)

    Engelfriet, Joost

    1976-01-01

    The surface tree languages obtained by top-down finite state transformation of monadic trees are exactly the frontier-preserving homomorphic images of sets of derivation trees of ETOL systems. The corresponding class of tree transformation languages is therefore equal to the class of ETOL languages.

  3. Percent Agricultural Land Cover on Steep Slopes (Future)

    Data.gov (United States)

    U.S. Environmental Protection Agency — Clearing land for agriculture tends to increase soil erosion. The amount of erosion is related to the steepness of the slope, farming methods used and soil type....

  4. Effect of Cover Crop Residues on Some Physicochemical Properties of Soil and Emergence Rate of Potato

    Directory of Open Access Journals (Sweden)

    M. Ghaffari

    2012-07-01

    Full Text Available The aim of this study, was to evaluate the effect of winter cover crop residues on speed of seed  potato emergence and percentage of organic carbon, soil specific weight and soil temperature. An experiment was carried out at the Research Farm of Agriculture Faculty, Bu-AliSinaUniversity, in 2008-2009. The experiment was a randomized complete block design with three replications. Winter cover crops consisted of rye, barley and oilseed rape, each one with common plant density (rye and barley at 190 kg.ha-1 and oilseed rape at 9 kg.ha-1 and triple plant densities(rye and barley 570 kg.ha-1 and oilseed rape, 27 kg.ha-1 and control (without cover crop. The results showed that rye and barley with triple plant densities produced higher biomass (1503.5 and 1392.2 g/m2, respectively than other treatments.Soil physicochemical properties were affected significantly by using cover crops. Rye, barley, and oilseed rape with triple rate and rye with common rape of plant densities produced, the highest organic carbon. Green manure of rye and barley with triple and rye with common rate plant densities, reduced soil specific weights by 17.3, 18 and 18 percent as compared with the control treatment (without cover crop planting. Rye and barley with triple plant densities increased average soil temperature by 12 and 11 percent respectively in comparison with control treatment. These treatments increased speed of seed potato emergence by 20 and 12 percent respectively as compared with that of control treatment, respectively. Other treatments showed no significant difference as compared to control. Cover crop residues increased plants speed of seed potato emergence through improving soil conditions.

  5. Using decision trees and their ensembles for analysis of NIR spectroscopic data

    DEFF Research Database (Denmark)

    Kucheryavskiy, Sergey V.

    and interpretation of the models. In this presentation, we are going to discuss an applicability of decision trees based methods (including gradient boosting) for solving classification and regression tasks with NIR spectra as predictors. We will cover such aspects as evaluation, optimization and validation......Advanced machine learning methods, like convolutional neural networks and decision trees, became extremely popular in the last decade. This, first of all, is directly related to the current boom in Big data analysis, where traditional statistical methods are not efficient. According to the kaggle.......com — the most popular online resource for Big data problems and solutions — methods based on decision trees and their ensembles are most widely used for solving the problems. It can be noted that the decision trees and convolutional neural networks are not very popular in Chemometrics. One of the reasons...

  6. TreePics: visualizing trees with pictures

    Directory of Open Access Journals (Sweden)

    Nicolas Puillandre

    2017-09-01

    Full Text Available While many programs are available to edit phylogenetic trees, associating pictures with branch tips in an efficient and automatic way is not an available option. Here, we present TreePics, a standalone software that uses a web browser to visualize phylogenetic trees in Newick format and that associates pictures (typically, pictures of the voucher specimens to the tip of each branch. Pictures are visualized as thumbnails and can be enlarged by a mouse rollover. Further, several pictures can be selected and displayed in a separate window for visual comparison. TreePics works either online or in a full standalone version, where it can display trees with several thousands of pictures (depending on the memory available. We argue that TreePics can be particularly useful in a preliminary stage of research, such as to quickly detect conflicts between a DNA-based phylogenetic tree and morphological variation, that may be due to contamination that needs to be removed prior to final analyses, or the presence of species complexes.

  7. An assessment of plant biointrusion at the Uranium Mill Tailings Remedial Action Project rock-covered disposal cells

    International Nuclear Information System (INIS)

    1990-10-01

    This study is one of a number of special studies that have been conducted regarding various aspects of the Uranium Mill Tailings Remedial Action (UMTRA) Project. This special study was proposed following routine surveillance and maintenance surveys and observations reported in a special study of vegetative covers (DOE, 1988), in which plants were observed growing up through the rock erosion layer at recently completed disposal cells. Some of the plants observed were deep-rooted woody species, and questions concerning root intrusion into disposal cells and the need to control plant growth were raised. The special study discussed in this report was designed to address some of the ramifications of plant growth on disposal cells that have rock covers. The NRC has chosen rock covers over vegetative covers in the arid western United States because licenses cannot substantiate that the vegetative covers ''will be significantly greater than 30 percent and preferably 70 percent,'' which is the amount of ''vegetation required to reduce flow to a point of stability.'' The potential impacts of vegetation growing in rock covers are not addressed by the NRC (1990). The objectives, then, of this study were to determine the species of plants growing on two rock-covered disposal cells, study the rooting pattern of plants on these cells, and identify possible impacts of plant root penetration on these and other UMTRA Project rock-covered cells

  8. Tree species diversity in the Eastern Ghats of northern Andhra Pradesh, India

    Directory of Open Access Journals (Sweden)

    M. Tarakeswara Naidu

    2015-06-01

    Full Text Available The present study was conducted to analyze tree species diversity in the tropical forests of the Eastern Ghats of northern Andhra Pradesh, India.  A total of 270 species of trees (≥15cm girth at breast height pertaining to 177 genera belonging to 55 families were recorded.  Among the 270 species, 141 species were observed to be common, 78 were occasional and 51 species were rare in the study area.  Fabaceae was the dominant family with 33 species followed by Rubiaceae with 15 species and Malvaceae, Moraceae and Phyllanthaceae with 13 species each.  The genera with the highest number of species include Ficus (12 species, Diospyros (8 species, Albizia and Grewia (6 species each, Acacia and Bauhinia (5 species each.  Forty-five percent of the species were indigenous. This illustrates the diversity of the tree species in the studied area of the Eastern Ghats and also emphasizes the need for their conservation. 

  9. A basic approach to fire injury of tree stems

    Science.gov (United States)

    R. E. Martin

    1963-01-01

    Fire has come to be widely used as a tool in wildland management, particularly in the South. Its usefulness in fire hazard reduction, removal of undesirable trees, and changing of cover types has been demonstrated. We are continually trying to improve fire use, however, by learning more of the specific effects of fire on different species of plants.

  10. Differences in breeding bird assemblages related to reed canary grass cover cover and forest structure on the Upper Mississippi River

    Science.gov (United States)

    Kirsch, Eileen M.; Gray, Brian R.

    2017-01-01

    Floodplain forest of the Upper Mississippi River provides habitat for an abundant and diverse breeding bird community. However, reed canary grass Phalaris arundinacea invasion is a serious threat to the future condition of this forest. Reed canary grass is a well-known aggressive invader of wetland systems in the northern tier states of the conterminous United States. Aided by altered flow regimes and nutrient inputs from agriculture, reed canary grass has formed dense stands in canopy gaps and forest edges, retarding tree regeneration. We sampled vegetation and breeding birds in Upper Mississippi River floodplain forest edge and interior areas to 1) measure reed canary grass cover and 2) evaluate whether the breeding bird assemblage responded to differences in reed canary grass cover. Reed canary grass was found far into forest interiors, and its cover was similar between interior and edge sites. Bird assemblages differed between areas with more or less reed canary grass cover (.53% cover breakpoint). Common yellowthroat Geothlypis trichas, black-capped chickadee Parus atricapillus, and rose-breasted grosbeak Pheucticus ludovicianus were more common and American redstart Setophaga ruticilla, great crested flycatcher Myiarchus crinitus, and Baltimore oriole Icterus galbula were less common in sites with more reed canary grass cover. Bird diversity and abundance were similar between sites with different reed canary grass cover. A stronger divergence in bird assemblages was associated with ground cover ,15%, resulting from prolonged spring flooding. These sites hosted more prothonotary warbler Protonotaria citrea, but they had reduced bird abundance and diversity compared to other sites. Our results indicate that frequently flooded sites may be important for prothonotary warblers and that bird assemblages shift in response to reed canary grass invasion.

  11. 3D Visualization of Trees Based on a Sphere-Board Model

    Directory of Open Access Journals (Sweden)

    Jiangfeng She

    2018-01-01

    Full Text Available Because of the smooth interaction of tree systems, the billboard and crossed-plane techniques of image-based rendering (IBR have been used for tree visualization for many years. However, both the billboard-based tree model (BBTM and the crossed-plane tree model (CPTM have several notable limitations; for example, they give an impression of slicing when viewed from the top side, and they produce an unimpressive stereoscopic effect and insufficient lighted effects. In this study, a sphere-board-based tree model (SBTM is proposed to eliminate these defects and to improve the final visual effects. Compared with the BBTM or CPTM, the proposed SBTM uses one or more sphere-like 3D geometric surfaces covered with a virtual texture, which can present more details about the foliage than can 2D planes, to represent the 3D outline of a tree crown. However, the profile edge presented by a continuous surface is overly smooth and regular, and when used to delineate the outline of a tree crown, it makes the tree appear very unrealistic. To overcome this shortcoming and achieve a more natural final visual effect of the tree model, an additional process is applied to the edge of the surface profile. In addition, the SBTM can better support lighted effects because of its cubic geometrical features. Interactive visualization effects for a single tree and a grove are presented in a case study of Sabina chinensis. The results show that the SBTM can achieve a better compromise between realism and performance than can the BBTM or CPTM.

  12. Mapping carbon storage in urban trees with multi-source remote sensing data: Relationships between biomass, land use, and demographics in Boston neighborhoods

    International Nuclear Information System (INIS)

    Raciti, Steve M.; Hutyra, Lucy R.; Newell, Jared D.

    2014-01-01

    High resolution maps of urban vegetation and biomass are powerful tools for policy-makers and community groups seeking to reduce rates of urban runoff, moderate urban heat island effects, and mitigate the effects of greenhouse gas emissions. We developed a very high resolution map of urban tree biomass, assessed the scale sensitivities in biomass estimation, compared our results with lower resolution estimates, and explored the demographic relationships in biomass distribution across the City of Boston. We integrated remote sensing data (including LiDAR-based tree height estimates) and field-based observations to map canopy cover and aboveground tree carbon storage at ∼ 1 m spatial scale. Mean tree canopy cover was estimated to be 25.5 ± 1.5% and carbon storage was 355 Gg (28.8 Mg C ha −1 ) for the City of Boston. Tree biomass was highest in forest patches (110.7 Mg C ha −1 ), but residential (32.8 Mg C ha −1 ) and developed open (23.5 Mg C ha −1 ) land uses also contained relatively high carbon stocks. In contrast with previous studies, we did not find significant correlations between tree biomass and the demographic characteristics of Boston neighborhoods, including income, education, race, or population density. The proportion of households that rent was negatively correlated with urban tree biomass (R 2 = 0.26, p = 0.04) and correlated with Priority Planting Index values (R 2 = 0.55, p = 0.001), potentially reflecting differences in land management among rented and owner-occupied residential properties. We compared our very high resolution biomass map to lower resolution biomass products from other sources and found that those products consistently underestimated biomass within urban areas. This underestimation became more severe as spatial resolution decreased. This research demonstrates that 1) urban areas contain considerable tree carbon stocks; 2) canopy cover and biomass may not be related to the demographic characteristics of Boston

  13. Ecology and management of the Prairie Division

    Science.gov (United States)

    Roger C. Anderson

    2012-01-01

    Grasslands occurred on all continents, comprised almost 42 percent of the world’s plant cover, and once covered approximately 46 million km2 of the Earth’s surface. Grasslands contain few trees or shrubs, are dominated by grasses (members of the family Poaceae), and have a mixture of nongraminoid herbaceous species called forbs. Plant families...

  14. Remnant Trees in Enrichment Planted Gaps in Quintana Roo, Mexico: Reasons for Retention and Effects on Seedlings

    Directory of Open Access Journals (Sweden)

    Angélica Navarro-Martínez

    2017-07-01

    Full Text Available Natural forest management in the tropics is often impeded by scarcity of advanced regeneration of commercial species. To supplement natural regeneration in a forest managed by a community in the Selva Maya of Mexico, nursery-grown Swietenia macrophylla seedlings were planted in multiple-tree felling gaps, known as bosquetes. Remnant trees are often left standing in gaps for cultural and economic reasons or due to their official protected status. We focus on these purposefully retained trees and their impacts on planted seedlings. Sampled bosquetes were 400–1800 m2, of which remnant trees covered a mean of 29%. Seedling height growth rates over the first 18 months after out-planting more than doubled with increased canopy openness from 0.09 m year−1 under medium cover to 0.22 m year−1 in full sun. Liana infestations and shoot tip damage were most frequent on seedlings in the open, but, contrary to our expectations, height growth rates were 0.14 m year−1 faster for liana-infested seedlings than non-infested and did not differ between damaged and undamaged seedlings. Apparently the more rapid height growth of well-illuminated seedlings more than compensated for the effects of lianas or shoot tip damage. Despite the abundance of remnant trees and their negative effects on seedling growth, enrichment planting in bosquetes has potential for community-based natural forest management in the tropics in supplementing natural regeneration of commercial species. One obvious recommendation is to leave fewer remnant trees, especially those of commercial species that are non-merchantable due to stem defects and trees retained for no apparent reason, which together constituted half of the remnant crown cover in the sampled bosquetes. Finally, given the rapid growth of lianas and understory palms in large canopy gaps, at least the most vigorous of the planted seedlings should be tended for at least two years.

  15. Climatic Change over the 'Third Pole' from Long Tree-Ring Records

    Science.gov (United States)

    Cook, E.

    2011-12-01

    Climatic change over the Greater Himalayas and Tibetan Plateau, the 'Third Pole' of the world, is of great concern now as the Earth continues to warm at an alarming rate. While future climatic change over this region and its resulting impacts on humanity and the environment are difficult to predict with much certainty, knowing how climate has varied in the past can provide both an improved understanding of the range of variability and change that could occur in the future and the necessary context for assessing recent observed climatic change there. For this purpose, one of the best natural archives of past climate information available for study of the Third Pole environment is the changing pattern of annual ring widths found in long tree-ring chronologies. The forests of the Third Pole support many long-lived tree species, with some having life spans in excess of 1,000 years. This natural resource is steadily dwindling now due to continuing deforestation caused by human activity, but there is still enough remaining forest cover to produce a detailed network of long tree-ring chronologies for study of climate variability and change covering the past several centuries. The tree-ring records provide a mix of climate information, including that related to both temperature and precipitation. Examples of long drought-sensitive tree-ring records from the more arid parts of the Karakoram and Tibetan Plateau will be presented, along with records that primarily reflect changing temperatures in moister environments such as in Bhutan. Together they provide a glimpse of how climate of the Third Pole has changed over the past several centuries, the range of natural variability that could occur in the future independent of changes caused by greenhouse warming, and how changes during the latter part of the 20th century period of rapid global warming compare to the past.

  16. Specific gravity and other properties of wood and bark for 156 tree species found in North America

    Science.gov (United States)

    Patrick D. Miles

    2009-01-01

    This paper reports information for the estimation of biomass for 156 tree species found in North America for use in national forest inventory applications. We present specific gravities based on average green volume as well as 12 percent moisture content volume for calculation of oven-dry biomass....

  17. Temporal expansion of annual crop classification layers for the CONUS using the C5 decision tree classifier

    Science.gov (United States)

    Friesz, Aaron M.; Wylie, Bruce K.; Howard, Daniel M.

    2017-01-01

    Crop cover maps have become widely used in a range of research applications. Multiple crop cover maps have been developed to suite particular research interests. The National Agricultural Statistics Service (NASS) Cropland Data Layers (CDL) are a series of commonly used crop cover maps for the conterminous United States (CONUS) that span from 2008 to 2013. In this investigation, we sought to contribute to the availability of consistent CONUS crop cover maps by extending temporal coverage of the NASS CDL archive back eight additional years to 2000 by creating annual NASS CDL-like crop cover maps derived from a classification tree model algorithm. We used over 11 million records to train a classification tree algorithm and develop a crop classification model (CCM). The model was used to create crop cover maps for the CONUS for years 2000–2013 at 250 m spatial resolution. The CCM and the maps for years 2008–2013 were assessed for accuracy relative to resampled NASS CDLs. The CCM performed well against a withheld test data set with a model prediction accuracy of over 90%. The assessment of the crop cover maps indicated that the model performed well spatially, placing crop cover pixels within their known domains; however, the model did show a bias towards the ‘Other’ crop cover class, which caused frequent misclassifications of pixels around the periphery of large crop cover patch clusters and of pixels that form small, sparsely dispersed crop cover patches.

  18. ColorTree: a batch customization tool for phylogenic trees.

    Science.gov (United States)

    Chen, Wei-Hua; Lercher, Martin J

    2009-07-31

    Genome sequencing projects and comparative genomics studies typically aim to trace the evolutionary history of large gene sets, often requiring human inspection of hundreds of phylogenetic trees. If trees are checked for compatibility with an explicit null hypothesis (e.g., the monophyly of certain groups), this daunting task is greatly facilitated by an appropriate coloring scheme. In this note, we introduce ColorTree, a simple yet powerful batch customization tool for phylogenic trees. Based on pattern matching rules, ColorTree applies a set of customizations to an input tree file, e.g., coloring labels or branches. The customized trees are saved to an output file, which can then be viewed and further edited by Dendroscope (a freely available tree viewer). ColorTree runs on any Perl installation as a stand-alone command line tool, and its application can thus be easily automated. This way, hundreds of phylogenic trees can be customized for easy visual inspection in a matter of minutes. ColorTree allows efficient and flexible visual customization of large tree sets through the application of a user-supplied configuration file to multiple tree files.

  19. Environmental and microbial factors influencing methane and nitrous oxide fluxes in Mediterranean cork oak woodlands: trees make a difference.

    Science.gov (United States)

    Shvaleva, Alla; Siljanen, Henri M P; Correia, Alexandra; Costa E Silva, Filipe; Lamprecht, Richard E; Lobo-do-Vale, Raquel; Bicho, Catarina; Fangueiro, David; Anderson, Margaret; Pereira, João S; Chaves, Maria M; Cruz, Cristina; Martikainen, Pertti J

    2015-01-01

    Cork oak woodlands (montado) are agroforestry systems distributed all over the Mediterranean basin with a very important social, economic and ecological value. A generalized cork oak decline has been occurring in the last decades jeopardizing its future sustainability. It is unknown how loss of tree cover affects microbial processes that are consuming greenhouse gases in the montado ecosystem. The study was conducted under two different conditions in the natural understory of a cork oak woodland in center Portugal: under tree canopy (UC) and open areas without trees (OA). Fluxes of methane and nitrous oxide were measured with a static chamber technique. In order to quantify methanotrophs and bacteria capable of nitrous oxide consumption, we used quantitative real-time PCR targeting the pmoA and nosZ genes encoding the subunit of particulate methane mono-oxygenase and catalytic subunit of the nitrous oxide reductase, respectively. A significant seasonal effect was found on CH4 and N2O fluxes and pmoA and nosZ gene abundance. Tree cover had no effect on methane fluxes; conversely, whereas the UC plots were net emitters of nitrous oxide, the loss of tree cover resulted in a shift in the emission pattern such that the OA plots were a net sink for nitrous oxide. In a seasonal time scale, the UC had higher gene abundance of Type I methanotrophs. Methane flux correlated negatively with abundance of Type I methanotrophs in the UC plots. Nitrous oxide flux correlated negatively with nosZ gene abundance at the OA plots in contrast to that at the UC plots. In the UC soil, soil organic matter had a positive effect on soil extracellular enzyme activities, which correlated positively with the N2O flux. Our results demonstrated that tree cover affects soil properties, key enzyme activities and abundance of microorganisms and, consequently net CH4 and N2O exchange.

  20. Evaluation of Decision Trees for Cloud Detection from AVHRR Data

    Science.gov (United States)

    Shiffman, Smadar; Nemani, Ramakrishna

    2005-01-01

    Automated cloud detection and tracking is an important step in assessing changes in radiation budgets associated with global climate change via remote sensing. Data products based on satellite imagery are available to the scientific community for studying trends in the Earth's atmosphere. The data products include pixel-based cloud masks that assign cloud-cover classifications to pixels. Many cloud-mask algorithms have the form of decision trees. The decision trees employ sequential tests that scientists designed based on empirical astrophysics studies and simulations. Limitations of existing cloud masks restrict our ability to accurately track changes in cloud patterns over time. In a previous study we compared automatically learned decision trees to cloud masks included in Advanced Very High Resolution Radiometer (AVHRR) data products from the year 2000. In this paper we report the replication of the study for five-year data, and for a gold standard based on surface observations performed by scientists at weather stations in the British Islands. For our sample data, the accuracy of automatically learned decision trees was greater than the accuracy of the cloud masks p < 0.001.

  1. The rubber tree genome reveals new insights into rubber production and species adaptation

    OpenAIRE

    Tang, Chaorong; Yang, Meng; Fang, Yongjun; Luo, Yingfeng; Gao, Shenghan; Xiao, Xiaohu; An, Zewei; Zhou, Binhui; Zhang, Bing; Tan, Xinyu; Yeang, Hoong Yeet; Qin, Yunxia; Yang, Jianghua; Lin, Qiang; Mei, Hailiang

    2016-01-01

    The Para rubber tree (Hevea brasiliensis) is an economically important tropical tree species that produces natural rubber, an essential industrial raw material. Here we present a high-quality genome assembly of this species (1.37 Gb, scaffold N50 = 1.28 Mb) that covers 93.8% of the genome (1.47 Gb) and harbours 43,792 predicted protein-coding genes. A striking expansion of the REF/SRPP (rubber elongation factor/small rubber particle protein) gene family and its divergence into several laticif...

  2. Applications and Benefits for Big Data Sets Using Tree Distances and The T-SNE Algorithm

    Science.gov (United States)

    2016-03-01

    BENEFITS FOR BIG DATA SETS USING TREE DISTANCES AND THE T-SNE ALGORITHM by Suyoung Lee March 2016 Thesis Advisor: Samuel E. Buttrey...REPORT TYPE AND DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE APPLICATIONS AND BENEFITS FOR BIG DATA SETS USING TREE DISTANCES AND THE T-SNE...public release; distribution is unlimited 12b. DISTRIBUTION CODE 13. ABSTRACT (maximum 200 words ) Modern data sets often consist of unstructured data

  3. Accuracy Assessment of Satellite Derived Forest Cover Products in South and Southeast Asia

    Science.gov (United States)

    Gilani, H.; Xu, X.; Jain, A. K.

    2017-12-01

    South and Southeast Asia (SSEA) region occupies 16 % of worlds land area. It is home to over 50% of the world's population. The SSEA's countries are experiencing significant land-use and land-cover changes (LULCCs), primarily in agriculture, forest, and urban land. For this study, we compiled four existing global forest cover maps for year 2010 by Gong et al.(2015), Hansen et al. (2013), Sexton et al.(2013) and Shimada et al. (2014), which were all medium resolution (≤30 m) products based on Landsat and/or PALSAR satellite images. To evaluate the accuracy of these forest products, we used three types of information: (1) ground measurements, (2) high resolution satellite images and (3) forest cover maps produced at the national scale. The stratified random sampling technique was used to select a set of validation data points from the ground and high-resolution satellite images. Then the confusion matrix method was used to assess and rank the accuracy of the forest cover products for the entire SSEA region. We analyzed the spatial consistency of different forest cover maps, and further evaluated the consistency with terrain characteristics. Our study suggests that global forest cover mapping algorithms are trained and tested using limited ground measurement data. We found significant uncertainties in mountainous areas due to the topographical shadow effect and the dense tree canopies effects. The findings of this study will facilitate to improve our understanding of the forest cover dynamics and their impacts on the quantities and pathways of terrestrial carbon and nitrogen fluxes. Gong, P., et al. (2012). "Finer resolution observation and monitoring of global land cover: first mapping results with Landsat TM and ETM+ data." International Journal of Remote Sensing 34(7): 2607-2654. Hansen, M. C., et al. (2013). "High-Resolution Global Maps of 21st-Century Forest Cover Change." Science 342(6160): 850-853. Sexton, J. O., et al. (2013). "Global, 30-m resolution

  4. MULTI-TEMPORAL ASSESSMENT OF LYCHEE TREE CROP STRUCTURE USING MULTI-SPECTRAL RPAS IMAGERY

    Directory of Open Access Journals (Sweden)

    K. Johansen

    2017-08-01

    Full Text Available The lychee tree is native to China and produce small fleshy fruit up to 5 cm in diameter. Lychee production in Australia is worth > $20 million annually. Pruning of trees encourages new growth, has a positive effect on fruiting of lychee, makes fruit-picking easier, and may increase yield, as it increases light interception and tree crown surface area. The objective of this research was to assess changes in tree structure, i.e. tree crown circumference, width, height and Plant Projective Cover (PPC using multi-spectral Remotely Piloted Aircraft System (RPAS imagery collected before and after pruning of a lychee plantation. A secondary objective was to assess any variations in the results as a function of various flying heights (30, 50 and 70 m. Pre- and post-pruning results showed significant differences in all measured tree structural parameters, including an average decrease in: tree crown circumference of 1.94 m; tree crown width of 0.57 m; tree crown height of 0.62 m; and PPC of 14.8 %. The different flying heights produced similar measurements of tree crown width and PPC, whereas tree crown circumference and height measurements decreased with increasing flying height. These results show that multi-spectral RPAS imagery can provide a suitable means of assessing pruning efforts undertaken by contractors based on changes in tree structure of lychee plantations and that it is important to collect imagery in a consistent manner, as varying flying heights may cause changes to tree structural measurements.

  5. Evaluating Anthropogenic Risk of Grassland and Forest Habitat Degradation using Land-Cover Data

    Directory of Open Access Journals (Sweden)

    Kurt Riitters

    2009-09-01

    Full Text Available The effects of landscape context on habitat quality are receiving increased attention in conservation biology. The objective of this research is to demonstrate a landscape-level approach to mapping and evaluating the anthropogenic risks of grassland and forest habitat degradation by examining habitat context as defined by intensive anthropogenic land uses at multiple spatial scales. A landscape mosaic model classifies a given location according to the amounts of intensive agriculture and intensive development in its surrounding landscape, providing measures of anthropogenic risks attributable to habitat isolation and edge effects at that location. The model is implemented using a land-cover map (0.09 ha/pixel of the conterminous United States and six landscape sizes (4.4, 15.2, 65.6, 591, 5300, and 47800 ha to evaluate the spatial scales of anthropogenic risk. Statistics for grassland and forest habitat are extracted by geographic overlays of the maps of land-cover and landscape mosaics. Depending on landscape size, 81 to 94 percent of all grassland and forest habitat occurs in landscapes that are dominated by natural land-cover including habitat itself. Within those natural-dominated landscapes, 50 percent of grassland and 59 percent of forest is within 590 m of intensive agriculture and/or intensive developed land which is typically a minor component of total landscape area. The conclusion is that anthropogenic risk attributable to habitat patch isolation affects a small proportion of the total grassland or forest habitat area, while the majority of habitat area is exposed to edge effects.

  6. Land cover mapping of Greater Mesoamerica using MODIS data

    Science.gov (United States)

    Giri, Chandra; Jenkins, Clinton N.

    2005-01-01

    A new land cover database of Greater Mesoamerica has been prepared using moderate resolution imaging spectroradiometer (MODIS, 500 m resolution) satellite data. Daily surface reflectance MODIS data and a suite of ancillary data were used in preparing the database by employing a decision tree classification approach. The new land cover data are an improvement over traditional advanced very high resolution radiometer (AVHRR) based land cover data in terms of both spatial and thematic details. The dominant land cover type in Greater Mesoamerica is forest (39%), followed by shrubland (30%) and cropland (22%). Country analysis shows forest as the dominant land cover type in Belize (62%), Cost Rica (52%), Guatemala (53%), Honduras (56%), Nicaragua (53%), and Panama (48%), cropland as the dominant land cover type in El Salvador (60.5%), and shrubland as the dominant land cover type in Mexico (37%). A three-step approach was used to assess the quality of the classified land cover data: (i) qualitative assessment provided good insight in identifying and correcting gross errors; (ii) correlation analysis of MODIS- and Landsat-derived land cover data revealed strong positive association for forest (r2 = 0.88), shrubland (r2 = 0.75), and cropland (r2 = 0.97) but weak positive association for grassland (r2 = 0.26); and (iii) an error matrix generated using unseen training data provided an overall accuracy of 77.3% with a Kappa coefficient of 0.73608. Overall, MODIS 500 m data and the methodology used were found to be quite useful for broad-scale land cover mapping of Greater Mesoamerica.

  7. 26 CFR 301.6226(b)-1 - 5-percent group.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 18 2010-04-01 2010-04-01 false 5-percent group. 301.6226(b)-1 Section 301.6226... ADMINISTRATION PROCEDURE AND ADMINISTRATION Assessment In General § 301.6226(b)-1 5-percent group. (a) In general. All members of a 5-percent group shall join in filing any petition for judicial review. The...

  8. Forest dynamics in the temperate rainforests of Alaska: from individual tree to regional scales

    Science.gov (United States)

    Tara M. Barrett

    2015-01-01

    Analysis of remeasurement data from 1079 Forest Inventory and Analysis (FIA) plots revealed multi-scale change occurring in the temperate rainforests of southeast Alaska. In the western half of the region, including Prince William Sound, aboveground live tree biomass and carbon are increasing at a rate of 8 ( ± 2 ) percent per decade, driven by an increase in Sitka...

  9. Tree Colors: Color Schemes for Tree-Structured Data.

    Science.gov (United States)

    Tennekes, Martijn; de Jonge, Edwin

    2014-12-01

    We present a method to map tree structures to colors from the Hue-Chroma-Luminance color model, which is known for its well balanced perceptual properties. The Tree Colors method can be tuned with several parameters, whose effect on the resulting color schemes is discussed in detail. We provide a free and open source implementation with sensible parameter defaults. Categorical data are very common in statistical graphics, and often these categories form a classification tree. We evaluate applying Tree Colors to tree structured data with a survey on a large group of users from a national statistical institute. Our user study suggests that Tree Colors are useful, not only for improving node-link diagrams, but also for unveiling tree structure in non-hierarchical visualizations.

  10. TreePOD: Sensitivity-Aware Selection of Pareto-Optimal Decision Trees.

    Science.gov (United States)

    Muhlbacher, Thomas; Linhardt, Lorenz; Moller, Torsten; Piringer, Harald

    2018-01-01

    Balancing accuracy gains with other objectives such as interpretability is a key challenge when building decision trees. However, this process is difficult to automate because it involves know-how about the domain as well as the purpose of the model. This paper presents TreePOD, a new approach for sensitivity-aware model selection along trade-offs. TreePOD is based on exploring a large set of candidate trees generated by sampling the parameters of tree construction algorithms. Based on this set, visualizations of quantitative and qualitative tree aspects provide a comprehensive overview of possible tree characteristics. Along trade-offs between two objectives, TreePOD provides efficient selection guidance by focusing on Pareto-optimal tree candidates. TreePOD also conveys the sensitivities of tree characteristics on variations of selected parameters by extending the tree generation process with a full-factorial sampling. We demonstrate how TreePOD supports a variety of tasks involved in decision tree selection and describe its integration in a holistic workflow for building and selecting decision trees. For evaluation, we illustrate a case study for predicting critical power grid states, and we report qualitative feedback from domain experts in the energy sector. This feedback suggests that TreePOD enables users with and without statistical background a confident and efficient identification of suitable decision trees.

  11. Two Trees: Migrating Fault Trees to Decision Trees for Real Time Fault Detection on International Space Station

    Science.gov (United States)

    Lee, Charles; Alena, Richard L.; Robinson, Peter

    2004-01-01

    We started from ISS fault trees example to migrate to decision trees, presented a method to convert fault trees to decision trees. The method shows that the visualizations of root cause of fault are easier and the tree manipulating becomes more programmatic via available decision tree programs. The visualization of decision trees for the diagnostic shows a format of straight forward and easy understands. For ISS real time fault diagnostic, the status of the systems could be shown by mining the signals through the trees and see where it stops at. The other advantage to use decision trees is that the trees can learn the fault patterns and predict the future fault from the historic data. The learning is not only on the static data sets but also can be online, through accumulating the real time data sets, the decision trees can gain and store faults patterns in the trees and recognize them when they come.

  12. Characterization of the uranium--2 weight percent molybdenum alloy

    International Nuclear Information System (INIS)

    Hemperly, V.C.

    1976-01-01

    The uranium-2 wt percent molybdenum alloy was prepared, processed, and age hardened to meet a minimum 930-MPa yield strength (0.2 percent) with a minimum of 10 percent elongation. These mechanical properties were obtained with a carbon level up to 300 ppM in the alloy. The tensile-test ductility is lowered by the humidity of the laboratory atmosphere

  13. Intra-Urban Variability in Elemental Carbon Deposition to Tree Canopies

    Science.gov (United States)

    Barrett, T. E.; Ponette-González, A.; Rindy, J. E.; Sheesley, R. J.

    2017-12-01

    Urban areas cover biomass combustion, EC is a powerful climate-forcing agent and a significant component of fine particulate matter in urban atmospheres. Thus, understanding the factors that govern EC removal in urban areas could help mitigate climate change, while improving air quality for urban residents. EC particles can be removed from the atmosphere in precipitation (wet and fog deposition) or they can settle directly onto receptor surfaces (dry deposition). Only limited measurements indicate that EC deposition is higher in urban than in rural and remote regions. However, EC deposition likely exhibits considerable intra-urban variability, with tree canopies serving as potentially important sinks for EC on the cityscape. The goal of this research is to quantify spatial variability in total (wet + dry) EC deposition to urban tree canopies in the Dallas-Fort Worth Metroplex. Using a stratified non-random sampling design, 41 oak trees (22 post oak (Quercus stellata) and 19 live oak (Quercus virginiana)) were selected near (100 m) for measurements of throughfall (water that falls from the canopy to the forest floor). Additionally, 16 bulk rainfall samplers were deployed in grassy areas with no canopy cover. Results from one rain event indicate a volume weighted mean concentration of 83 µg EC L-1 in post oak throughfall, 36 µg EC L-1 in live oak throughfall, and 4 µg EC L-1 in bulk rainfall. Total EC deposition to oak tree canopies was 2.0 ± 2.1 (SD) mg m-2 for post oak and 0.7 ± 0.3 mg m-2 for live oak. Bulk rainfall deposition was 0.08 ± 0.1 mg m-2. Our preliminary findings show that trees are effective urban air filters, removing 9-25 times more EC from the atmosphere than rainwater alone. Resolving surface controls on atmospheric EC removal is key to developing and assessing near-term climate and air quality mitigation strategies.

  14. Abundance of large old trees in wood-pastures of Transylvania (Romania).

    Science.gov (United States)

    Hartel, Tibor; Hanspach, Jan; Moga, Cosmin I; Holban, Lucian; Szapanyos, Árpád; Tamás, Réka; Hováth, Csaba; Réti, Kinga-Olga

    2018-02-01

    Wood-pastures are special types of agroforestry systems that integrate trees with livestock grazing. Wood pastures can be hotspots for large old tree abundance and have exceptional natural values; but they are declining all over Europe. While presence of large old trees in wood-pastures can provide arguments for their maintenance, actual data on their distribution and abundance are sparse. Our study is the first to survey large old trees in Eastern Europe over such a large area. We surveyed 97 wood-pastures in Transylvania (Romania) in order to (i) provide a descriptive overview of the large old tree abundance; and (ii) to explore the environmental determinants of the abundance and persistence of large old trees in wood-pastures. We identified 2520 large old trees belonging to 16 taxonomic groups. Oak was present in 66% of the wood-pastures, followed by beech (33%), hornbeam (24%) and pear (22%). For each of these four species we constructed a generalized linear model with quasi-Poisson error distribution to explain individual tree abundance. Oak trees were most abundant in large wood-pastures and in wood-pastures from the Saxon cultural region of Transylvania. Beech abundance related positively to elevation and to proximity of human settlements. Abundance of hornbeam was highest in large wood-pastures, in wood-pastures from the Saxon cultural region, and in places with high cover of adjacent forest and a low human population density. Large old pear trees were most abundant in large wood-pastures that were close to paved roads. The maintenance of large old trees in production landscapes is a challenge for science, policy and local people, but it also can serve as an impetus for integrating economic, ecological and social goals within a landscape. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Lidar-based individual tree species classification using convolutional neural network

    Science.gov (United States)

    Mizoguchi, Tomohiro; Ishii, Akira; Nakamura, Hiroyuki; Inoue, Tsuyoshi; Takamatsu, Hisashi

    2017-06-01

    Terrestrial lidar is commonly used for detailed documentation in the field of forest inventory investigation. Recent improvements of point cloud processing techniques enabled efficient and precise computation of an individual tree shape parameters, such as breast-height diameter, height, and volume. However, tree species are manually specified by skilled workers to date. Previous works for automatic tree species classification mainly focused on aerial or satellite images, and few works have been reported for classification techniques using ground-based sensor data. Several candidate sensors can be considered for classification, such as RGB or multi/hyper spectral cameras. Above all candidates, we use terrestrial lidar because it can obtain high resolution point cloud in the dark forest. We selected bark texture for the classification criteria, since they clearly represent unique characteristics of each tree and do not change their appearance under seasonable variation and aged deterioration. In this paper, we propose a new method for automatic individual tree species classification based on terrestrial lidar using Convolutional Neural Network (CNN). The key component is the creation step of a depth image which well describe the characteristics of each species from a point cloud. We focus on Japanese cedar and cypress which cover the large part of domestic forest. Our experimental results demonstrate the effectiveness of our proposed method.

  16. Practical salinity management for leachate irrigation to poplar trees.

    Science.gov (United States)

    Smesrud, Jason K; Duvendack, George D; Obereiner, James M; Jordahl, James L; Madison, Mark F

    2012-01-01

    Landfill leachate can be beneficially reused for irrigation of fiber crops with appropriate attention to nutrient and salinity management. The Riverbend Landfill in Western Oregon has been effectively practicing irrigation of landfill leachate to poplar trees since 1993. Over that time, the site has been adaptively managed to control salinity impacts to the tree crop while beneficially utilizing the applied water and nutrients during each growing season. Representative leachate irrigation water has ranged in concentration of total dissolved solids from 777 to 6,940 mg/L, chloride from 180 to 1,760 mg/L and boron from 3.2 to 7.3 mg/L. Annual leachate irrigation applications have also ranged between 102 and 812 mm/yr. Important conclusions from this site have included: 1) Appropriate tree clone selection and tree stand spacing, thinning, and harvest rotations are critical to maintaining a productive tree stand that is resilient and resistant to salt stress. The most effective combinations have included clones DN-34, OP-367, 184-411, 49-177, and 15-29 planted at spacing of 3.7-m x 1.8-m to 3.7-m x 3.7-m; 2) Leaf tissue boron levels are closely correlated to soil boron levels and can be managed with leaching. When leaf tissue boron levels exceed 200 to 250 mg/kg, signs of salt stress may emerge and should be monitored closely; 3) Salinity from leachate irrigation can be managed to sustain a healthy tree crop by controlling mass loading rates and providing appropriate irrigation blending if necessary. Providing freshwater irrigation following each leachate irrigation and targeting freshwater irrigation as 30 percent of total irrigation water applied has successfully controlled salt impacts to vegetation; and 4) Drip irrigation generally requires more careful attention to long-term soil salinity management than spray irrigation. Moving drip irrigation tubes periodically to prevent the formation of highly saline zones within the soil profile is important. In this paper, a

  17. Soil Erosion and runoff response to plant-cover strips on semiarid slopes (SE Spain)

    NARCIS (Netherlands)

    Martinez-Raya, A.; Duran Zuazo, V.H.; Francia-Martinez, J.R.

    2006-01-01

    Over a four-year period (1997-2000), soil loss and surface-runoff patterns were monitored in hillside erosion plots with almond trees under different plant-cover strips (thyme, barley and lentils) on the south flank of the Sierra Nevada (Lanjaron) in south-eastern Spain. The erosion plots (580 m

  18. Observations on the fauna that visit African Tulip Tree (Spathodea campanulata Beauv.) forests in Puerto Rico

    Science.gov (United States)

    Oscar J. Abelleira Martinez

    2008-01-01

    Diurnal field observations in secondary forests dominated by the introduced African tulip tree (Spathodea campanulata) in Puerto Rico show a faunal assemblage that consists mostly of native species (81.1 percent). The most abundant species were common birds and reptiles, yet some uncommon fauna appear to be visiting or residing in these forests. The observations...

  19. A comprehensive emission inventory of biogenic volatile organic compounds in Europe: improved seasonality and land-cover

    Directory of Open Access Journals (Sweden)

    D. C. Oderbolz

    2013-02-01

    Full Text Available Biogenic volatile organic compounds (BVOC emitted from vegetation are important for the formation of secondary pollutants such as ozone and secondary organic aerosols (SOA in the atmosphere. Therefore, BVOC emission are an important input for air quality models. To model these emissions with high spatial resolution, the accuracy of the underlying vegetation inventory is crucial. We present a BVOC emission model that accommodates different vegetation inventories and uses satellite-based measurements of greenness instead of pre-defined vegetation periods. This approach to seasonality implicitly treats effects caused by water or nutrient availability, altitude and latitude on a plant stand. Additionally, we test the influence of proposed seasonal variability in enzyme activity on BVOC emissions. In its present setup, the emission model calculates hourly emissions of isoprene, monoterpenes, sesquiterpenes and the oxygenated volatile organic compounds (OVOC methanol, formaldehyde, formic acid, ethanol, acetaldehyde, acetone and acetic acid. In this study, emissions based on three different vegetation inventories are compared with each other and diurnal and seasonal variations in Europe are investigated for the year 2006. Two of these vegetation inventories require information on tree-cover as an input. We compare three different land-cover inventories (USGS GLCC, GLC2000 and Globcover 2.2 with respect to tree-cover. The often-used USGS GLCC land-cover inventory leads to a severe reduction of BVOC emissions due to a potential miss-attribution of broad-leaved trees and reduced tree-cover compared to the two other land-cover inventories. To account for uncertainties in the land-cover classification, we introduce land-cover correction factors for each relevant land-use category to adjust the tree-cover. The results are very sensitive to these factors within the plausible range. For June 2006, total monthly BVOC emissions decreased up to −27% with

  20. Assessment of the thematic accuracy of land cover maps

    DEFF Research Database (Denmark)

    Høhle, Joachim

    2015-01-01

    were applied (‘Decision Tree’ and ‘Support Vector Machine’) using only two attributes (height above ground and normalized difference vegetation index) which both are derived from the images. The assessment of the thematic accuracy applied a stratified design and was based on accuracy measures...... methods perform equally for five classes. Trees are classified with a much better accuracy and a smaller confidence interval by means of the decision tree method. Buildings are classified by both methods with an accuracy of 99% (95% CI: 95%-100%) using independent 3D checkpoints. The average width......Several land cover maps are generated from aerial imagery and assessed by different approaches. The test site is an urban area in Europe for which six classes (‘building’, ‘hedge and bush’, ‘grass’, ‘road and parking lot’, ‘tree’, ‘wall and car port’) had to be derived. Two classification methods...

  1. Avian species richness in relation to intensive forest management practices in early seral tree plantations.

    Science.gov (United States)

    Jones, Jay E; Kroll, Andrew J; Giovanini, Jack; Duke, Steven D; Ellis, Tana M; Betts, Matthew G

    2012-01-01

    Managers of landscapes dedicated to forest commodity production require information about how practices influence biological diversity. Individual species and communities may be threatened if management practices truncate or simplify forest age classes that are essential for reproduction and survival. For instance, the degradation and loss of complex diverse forest in young age classes have been associated with declines in forest-associated Neotropical migrant bird populations in the Pacific Northwest, USA. These declines may be exacerbated by intensive forest management practices that reduce hardwood and broadleaf shrub cover in order to promote growth of economically valuable tree species in plantations. We used a Bayesian hierarchical model to evaluate relationships between avian species richness and vegetation variables that reflect stand management intensity (primarily via herbicide application) on 212 tree plantations in the Coast Range, Oregon, USA. Specifically, we estimated the influence of broadleaf hardwood vegetation cover, which is reduced through herbicide applications, on bird species richness and individual species occupancy. Our model accounted for imperfect detection. We used average predictive comparisons to quantify the degree of association between vegetation variables and species richness. Both conifer and hardwood cover were positively associated with total species richness, suggesting that these components of forest stand composition may be important predictors of alpha diversity. Estimates of species richness were 35-80% lower when imperfect detection was ignored (depending on covariate values), a result that has critical implications for previous efforts that have examined relationships between forest composition and species richness. Our results revealed that individual and community responses were positively associated with both conifer and hardwood cover. In our system, patterns of bird community assembly appear to be associated with

  2. Mapping carbon storage in urban trees with multi-source remote sensing data: Relationships between biomass, land use, and demographics in Boston neighborhoods

    Energy Technology Data Exchange (ETDEWEB)

    Raciti, Steve M., E-mail: Steve.M.Raciti@Hofstra.edu [Department of Biology, Hofstra University, Gittleson Hall, Hempstead, NY 11549 (United States); Department of Earth and Environment, Boston University, 685 Commonwealth Ave., Boston, MA 02215 (United States); Hutyra, Lucy R.; Newell, Jared D. [Department of Earth and Environment, Boston University, 685 Commonwealth Ave., Boston, MA 02215 (United States)

    2014-12-01

    High resolution maps of urban vegetation and biomass are powerful tools for policy-makers and community groups seeking to reduce rates of urban runoff, moderate urban heat island effects, and mitigate the effects of greenhouse gas emissions. We developed a very high resolution map of urban tree biomass, assessed the scale sensitivities in biomass estimation, compared our results with lower resolution estimates, and explored the demographic relationships in biomass distribution across the City of Boston. We integrated remote sensing data (including LiDAR-based tree height estimates) and field-based observations to map canopy cover and aboveground tree carbon storage at ∼ 1 m spatial scale. Mean tree canopy cover was estimated to be 25.5 ± 1.5% and carbon storage was 355 Gg (28.8 Mg C ha{sup −1}) for the City of Boston. Tree biomass was highest in forest patches (110.7 Mg C ha{sup −1}), but residential (32.8 Mg C ha{sup −1}) and developed open (23.5 Mg C ha{sup −1}) land uses also contained relatively high carbon stocks. In contrast with previous studies, we did not find significant correlations between tree biomass and the demographic characteristics of Boston neighborhoods, including income, education, race, or population density. The proportion of households that rent was negatively correlated with urban tree biomass (R{sup 2} = 0.26, p = 0.04) and correlated with Priority Planting Index values (R{sup 2} = 0.55, p = 0.001), potentially reflecting differences in land management among rented and owner-occupied residential properties. We compared our very high resolution biomass map to lower resolution biomass products from other sources and found that those products consistently underestimated biomass within urban areas. This underestimation became more severe as spatial resolution decreased. This research demonstrates that 1) urban areas contain considerable tree carbon stocks; 2) canopy cover and biomass may not be related to the demographic

  3. The relationships between percent body fat and other ...

    African Journals Online (AJOL)

    The relationships between percent body fat and other anthropometric nutritional predictors among male and female children in Nigeria. ... A weak significant positive correlation was observed between the percent body fat and height – armspan ratio ... There was evidence of overweight and obesity in both children. The mid ...

  4. Tree Nut Allergies

    Science.gov (United States)

    ... Blog Vision Awards Common Allergens Tree Nut Allergy Tree Nut Allergy Learn about tree nut allergy, how ... a Tree Nut Label card . Allergic Reactions to Tree Nuts Tree nuts can cause a severe and ...

  5. Germination and Seedling Development of Seeds from Different Parkia biglobosa (Jacq G. Don Trees

    Directory of Open Access Journals (Sweden)

    Christiana O. ADEYEMI

    2013-02-01

    Full Text Available The effect of daylight, continuous illumination and acid scarification on the seed germination and seedling vegetative growth (epicotyl and hypocotyl lengths, and number of secondary roots of different Parkia biglobosawere investigated in the Plant Physiology Laboratory University of Ilorin, Ilorin Kwara State Nigeria. Seeds from two out of the twenty six Parkia tree samples (trees B and T germinated within 24 hours of planting in the daylight germination study while seeds from another tree (Q did not germinate until the third week after planting (3WAP. Some seeds have higher germination percentage both in the daylight (preliminary germination study and in the continuous light (illuminated study. The treatment with concentrated Sulphric acid (conc. H2SO4was effective in breaking the seed dormancy as seeds from eight (8 trees produced one hundred percent (100% germination. At p= 0.05 the length of epicotyl and hypocoty1 lengths were significantly different as seedling vegetative growth were long in the seedlings from the daylight experiment than the continuous light experiment. The vegetative growths of the seedlings from the scarified seed were longer at 15min of scarification in all except in trees F and Z. It was observed that the time of scarification affect the both seed germination and seedling development.

  6. Reduced aboveground tree growth associated with higher arbuscular mycorrhizal fungal diversity in tropical forest restoration.

    Science.gov (United States)

    Holste, Ellen K; Holl, Karen D; Zahawi, Rakan A; Kobe, Richard K

    2016-10-01

    Establishing diverse mycorrhizal fungal communities is considered important for forest recovery, yet mycorrhizae may have complex effects on tree growth depending on the composition of fungal species present. In an effort to understand the role of mycorrhizal fungi community in forest restoration in southern Costa Rica, we sampled the arbuscular mycorrhizal fungal (AMF) community across eight sites that were planted with the same species ( Inga edulis, Erythrina poeppigiana, Terminalia amazonia, and Vochysia guatemalensis ) but varied twofold to fourfold in overall tree growth rates. The AMF community was measured in multiple ways: as percent colonization of host tree roots, by DNA isolation of the fungal species associated with the roots, and through spore density, volume, and identity in both the wet and dry seasons. Consistent with prior tropical restoration research, the majority of fungal species belonged to the genus Glomus and genus Acaulospora , accounting for more than half of the species and relative abundance found on trees roots and over 95% of spore density across all sites. Greater AMF diversity correlated with lower soil organic matter, carbon, and nitrogen concentrations and longer durations of prior pasture use across sites. Contrary to previous literature findings, AMF species diversity and spore densities were inversely related to tree growth, which may have arisen from trees facultatively increasing their associations with AMF in lower soil fertility sites. Changes to AMF community composition also may have led to variation in disturbance susceptibility, host tree nutrient acquisition, and tree growth. These results highlight the potential importance of fungal-tree-soil interactions in forest recovery and suggest that fungal community dynamics could have important implications for tree growth in disturbed soils.

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

    Indian Academy of Sciences (India)

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

  8. Humic substances and its distribution in coffee crop under cover crops and weed control methods

    Directory of Open Access Journals (Sweden)

    Bruno Henrique Martins

    2016-08-01

    Full Text Available ABSTRACT Humic substances (HS comprise the passive element in soil organic matter (SOM, and represent one of the soil carbon pools which may be altered by different cover crops and weed control methods. This study aimed to assess HS distribution and characteristics in an experimental coffee crop area subjected to cover crops and cultural, mechanical, and chemical weed control. The study was carried out at Londrina, in the state of Paraná, southern Brazil (23°21’30” S; 51°10’17” W. In 2008, seven weed control/cover crops were established in a randomized block design between two coffee rows as the main-plot factor per plot and soil sampling depths (0-10 cm, 10-20 cm, 20-30 cm and 30-40 cm as a split-plot. HS were extracted through alkaline and acid solutions and analyzed by chromic acid wet oxidation and UV-Vis spectroscopy. Chemical attributes presented variations in the topsoil between the field conditions analyzed. Cover crop cutting and coffee tree pruning residues left on the soil surface may have interfered in nutrient cycling and the humification process. Data showed that humic substances comprised about 50 % of SOM. Although different cover crops and weed control methods did not alter humic and fulvic acid carbon content, a possible incidence of condensed aromatic structures at depth increments in fulvic acids was observed, leading to an average decrease of 53 % in the E4/E6 ratio. Humin carbon content increased 25 % in the topsoil, particularly under crop weed-control methods, probably due to high incorporation of recalcitrant structures from coffee tree pruning residues and cover crops.

  9. Influence of the date of cut of rootstocks to the stub on growth of maider sour cherry trees cv. 'Łutówka'

    Directory of Open Access Journals (Sweden)

    Stanisław Wociór

    2013-12-01

    Full Text Available Over a three-year period (1997-1999 investigations were conducted on the effect of 6 date of cut to the stub on tree trunk diameter, height and branching of sour cherry maidens in the nursery.On the Prunus mahaleb seedling rootstock were found no significant influen ce of the date between January, 15 - March, 30 of cut to the stub on growth of sour cherry maidens cv. ´Łutówka' (tree trunk diameter and branching and efficiency of nursery. The date of cutting in 15 April decreased trunk diameter and percent of the first quality trees.

  10. Benthic percent cover derived from analysis of benthic images collected at coral reef sites in Timor-Leste in 2013 and 2014

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The benthic cover data described here result from benthic photo-quadrat surveys conducted by the NOAA Coral Reef Ecosystem Program (CREP) in hard bottom shallow...

  11. Big trees, old trees, and growth factor tables

    Science.gov (United States)

    Kevin T. Smith

    2018-01-01

    The potential for a tree to reach a great size and to live a long life frequently captures the public's imagination. Sometimes the desire to know the age of an impressively large tree is simple curiosity. For others, the date-of-tree establishment can make a big diff erence for management, particularly for trees at historic sites or those mentioned in property...

  12. A Suffix Tree Or Not a Suffix Tree?

    DEFF Research Database (Denmark)

    Starikovskaya, Tatiana; Vildhøj, Hjalte Wedel

    2015-01-01

    In this paper we study the structure of suffix trees. Given an unlabeled tree r on n nodes and suffix links of its internal nodes, we ask the question “Is r a suffix tree?”, i.e., is there a string S whose suffix tree has the same topological structure as r? We place no restrictions on S, in part...

  13. Nitrous oxide fluxes from forest floor, tree stems and canopies of boreal tree species during spring

    Science.gov (United States)

    Haikarainen, Iikka; Halmeenmäki, Elisa; Machacova, Katerina; Pihlatie, Mari

    2017-04-01

    Boreal forests are considered as small sources of atmospheric nitrous oxide (N2O) due to microbial N2O production in the soils. Recent evidence shows that trees may play an important role in N2O exchange of forest ecosystems by offering pathways for soil produced N2O to the atmosphere. To confirm magnitude, variability and the origin of the tree mediated N2O emissions more research is needed, especially in boreal forests which have been in a minority in such investigation. We measured forest floor, tree stem and shoot N2O exchange of three boreal tree species at the beginning of the growing season (13.4.-13.6.2015) at SMEAR II station in Hyytiälä, located in Southern Finland (61˚ 51´N, 24˚ 17´E, 181 a.s.l.). The fluxes were measured in silver birch (Betula pendula), downy birch (B. pubescens) and Norway spruce (Picea abies) on two sites with differing soil type and characteristics (paludified and mineral soil), vegetation cover and forest structure. The aim was to study the vertical profile of N2O fluxes at stem level and to observe temporal changes in N2O fluxes over the beginning of the growing season. The N2O exchange was determined using the static chamber technique and gas chromatographic analyses. Scaffold towers were used for measurements at multiple stem heights and at the canopy level. Overall, the N2O fluxes from the forest floor and trees at both sites were very small and close to the detection limit. The measured trees mainly emitted N2O from their stems and shoots, while the forest floor acted as a sink of N2O at the paludified site and as a small source of N2O at the mineral soil site. Stem emissions from all the trees at both sites were on average below 0.5 μg N2O m-2 of stem area h-1, and the shoot emissions varied between 0.2 and 0.5 ng N2O m-2 g-1 dry biomass. When the N2O fluxes were scaled up to the whole forest ecosystem, based on the tree biomass and stand density, the N2O emissions from birch and spruce trees at the paludified site

  14. Temperate forest and open landscapes are distinct alternative states as reflected in canopy height and tree cover

    NARCIS (Netherlands)

    Xu, Chi; Vergnon, Remi; Cornelissen, J.H.C.; Hantson, S.; Holmgren, M.; Nes, van E.H.; Scheffer, M.

    2015-01-01

    The suggestion that woody plants of intermediate height between trees and shrubs (‘trubs’) are conspicuously rare [1] invoked much interest. Two comments showed regional species lists that did not have this paucity of medium-sized woody plants 2 and 3. In response, we hypothesized that the

  15. Above- and Belowground Biomass Models for Trees in the Miombo Woodlands of Malawi

    Directory of Open Access Journals (Sweden)

    Daud J. Kachamba

    2016-02-01

    Full Text Available In this study we present general (multiple tree species from several sites above- and belowground biomass models for trees in the miombo woodlands of Malawi. Such models are currently lacking in the country. The modelling was based on 74 trees comprising 33 different species with diameters at breast height (dbh and total tree height (ht ranging from 5.3 to 2 cm and from 3.0 to 25.0 m, respectively. Trees were collected from four silvicultural zones covering a wide range of conditions. We tested different models including dbh, ht and wood specific gravity ( ρ as independent variables. We evaluated model performance using pseudo-R2, root mean square error (RMSE, a covariance matrix for the parameter estimates, mean prediction error (MPE and relative mean prediction error (MPE%. Computation of MPE% was based on leave-one-out cross-validation. Values of pseudo-R2 and MPE% ranged 0.82–0.97 and 0.9%–2.8%, respectively. Model performance indicated that the models can be used over a wide range of geographical and ecological conditions in Malawi.

  16. Use of UAV-Borne Spectrometer for Land Cover Classification

    Directory of Open Access Journals (Sweden)

    Sowmya Natesan

    2018-04-01

    Full Text Available Unmanned aerial vehicles (UAV are being used for low altitude remote sensing for thematic land classification using visible light and multi-spectral sensors. The objective of this work was to investigate the use of UAV equipped with a compact spectrometer for land cover classification. The UAV platform used was a DJI Flamewheel F550 hexacopter equipped with GPS and Inertial Measurement Unit (IMU navigation sensors, and a Raspberry Pi processor and camera module. The spectrometer used was the FLAME-NIR, a near-infrared spectrometer for hyperspectral measurements. RGB images and spectrometer data were captured simultaneously. As spectrometer data do not provide continuous terrain coverage, the locations of their ground elliptical footprints were determined from the bundle adjustment solution of the captured images. For each of the spectrometer ground ellipses, the land cover signature at the footprint location was determined to enable the characterization, identification, and classification of land cover elements. To attain a continuous land cover classification map, spatial interpolation was carried out from the irregularly distributed labeled spectrometer points. The accuracy of the classification was assessed using spatial intersection with the object-based image classification performed using the RGB images. Results show that in homogeneous land cover, like water, the accuracy of classification is 78% and in mixed classes, like grass, trees and manmade features, the average accuracy is 50%, thus, indicating the contribution of hyperspectral measurements of low altitude UAV-borne spectrometers to improve land cover classification.

  17. Mapping Woodland Cover in the Miombo Ecosystem: A Comparison of Machine Learning Classifiers

    Directory of Open Access Journals (Sweden)

    Courage Kamusoko

    2014-06-01

    Full Text Available Miombo woodlands in Southern Africa are experiencing accelerated changes due to natural and anthropogenic disturbances. In order to formulate sustainable woodland management strategies in the Miombo ecosystem, timely and up-to-date land cover information is required. Recent advances in remote sensing technology have improved land cover mapping in tropical evergreen ecosystems. However, woodland cover mapping remains a challenge in the Miombo ecosystem. The objective of the study was to evaluate the performance of decision trees (DT, random forests (RF, and support vector machines (SVM in the context of improving woodland and non-woodland cover mapping in the Miombo ecosystem in Zimbabwe. We used Multidate Landsat 8 spectral and spatial dependence (Moran’s I variables to map woodland and non-woodland cover. Results show that RF classifier outperformed the SVM and DT classifiers by 4% and 15%, respectively. The RF importance measures show that multidate Landsat 8 spectral and spatial variables had the greatest influence on class-separability in the study area. Therefore, the RF classifier has potential to improve woodland cover mapping in the Miombo ecosystem.

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

    NARCIS (Netherlands)

    Eilmann, B.; Rigling, A.

    2012-01-01

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

  19. Can dendrochronology procedures estimate historical Tree Water Footprint?

    Science.gov (United States)

    Fernandes, Tarcísio J. G.; Del Campo, Antonio D.; Molina, Antonio J.

    2013-04-01

    Whole estimates of tree water use are becoming increasingly important in forest science and forest scientists have long sought to develop reliable techniques to estimate tree water use. In this sense accurately determining or estimate the quantity of water transpired by trees and forests is important and can be used to determine "green" water footprint. The use of dendrochronology is relative common in the study of effects and interactions between growth and climatic variables, but few studies deal with the relationship with water footprint. The main objective of this study is determining the historical tree water-use in a planted stand by dendrochronological approaches. This study was performed in South-eastern Spain, in an area covered by 50-60 years old Pinus halepensis Mil. plantations with high tree density (ca.1288/ha) due to low forest management. The experimental set-up consisted of two plots (30x30m), one corresponding to a thinning treatment performed in 2008 (t10) and the other thinned in 1998 (t1) to assess the mid-term effects of thinning. After one year of thinning four representative trees were select in each plot to measure transpiration by heat pulse sensor (sapflow velocity, vs). The accumulated daily values of transpiration (L day-1) were estimated multiplying the values of vs by sapwood area of each selected tree. After transpiration measurements two cores per tree were taken for establishing the tree-rings chronologies. The cores were prepared, their ring-width were measured and standardised in basal area increment index (BAI-i) following usual dendrochronological methods. The dendrochronology analyses showed a general variability in ring width during the initial growth (15 years), while in the following years the width rings were very small, conditioned by climate. The year after thinning (1999 or 2009) all trees in the treatments showed significant increases in ring width. The average vs for t1 and t10 were 3.59 cm h-1 and 1.95 cm h-1, and

  20. Modeled PM2.5 removal by trees in ten U.S. cities and associated health effects

    International Nuclear Information System (INIS)

    Nowak, David J.; Hirabayashi, Satoshi; Bodine, Allison; Hoehn, Robert

    2013-01-01

    Urban particulate air pollution is a serious health issue. Trees within cities can remove fine particles from the atmosphere and consequently improve air quality and human health. Tree effects on PM 2.5 concentrations and human health are modeled for 10 U.S. cities. The total amount of PM 2.5 removed annually by trees varied from 4.7 tonnes in Syracuse to 64.5 tonnes in Atlanta, with annual values varying from $1.1 million in Syracuse to $60.1 million in New York City. Most of these values were from the effects of reducing human mortality. Mortality reductions were typically around 1 person yr −1 per city, but were as high as 7.6 people yr −1 in New York City. Average annual percent air quality improvement ranged between 0.05% in San Francisco and 0.24% in Atlanta. Understanding the impact of urban trees on air quality can lead to improved urban forest management strategies to sustain human health in cities. -- Highlights: •Paper provides the first broad-scale estimates of city-wide tree impacts on PM 2.5 . •Trees improve overall air quality by intercepting particulate matter. •Particle resuspension can lead to short-term increases in pollutant concentrations. •Urban trees produce substantial health improvements and values. -- Air pollution modeling reveals broad-scale impacts of pollution removal by urban trees on PM 2.5 concentrations and human health

  1. TreeNetViz: revealing patterns of networks over tree structures.

    Science.gov (United States)

    Gou, Liang; Zhang, Xiaolong Luke

    2011-12-01

    Network data often contain important attributes from various dimensions such as social affiliations and areas of expertise in a social network. If such attributes exhibit a tree structure, visualizing a compound graph consisting of tree and network structures becomes complicated. How to visually reveal patterns of a network over a tree has not been fully studied. In this paper, we propose a compound graph model, TreeNet, to support visualization and analysis of a network at multiple levels of aggregation over a tree. We also present a visualization design, TreeNetViz, to offer the multiscale and cross-scale exploration and interaction of a TreeNet graph. TreeNetViz uses a Radial, Space-Filling (RSF) visualization to represent the tree structure, a circle layout with novel optimization to show aggregated networks derived from TreeNet, and an edge bundling technique to reduce visual complexity. Our circular layout algorithm reduces both total edge-crossings and edge length and also considers hierarchical structure constraints and edge weight in a TreeNet graph. These experiments illustrate that the algorithm can reduce visual cluttering in TreeNet graphs. Our case study also shows that TreeNetViz has the potential to support the analysis of a compound graph by revealing multiscale and cross-scale network patterns. © 2011 IEEE

  2. Influence of avenue-trees on air quality at the urban neighborhood scale. Part II: traffic pollutant concentrations at pedestrian level.

    Science.gov (United States)

    Gromke, Christof; Blocken, Bert

    2015-01-01

    Flow and dispersion of traffic-emitted pollutants were studied in a generic urban neighborhood for various avenue-tree layouts by employing 3D steady RANS simulations with the realizable k-ε turbulence model. In comparison to the tree-free situation quantitative and qualitative changes with flow reversal in the wind field were observed. Low to moderate increases (pollutant concentration were found at pedestrian level. An approximately 1% increase in the neighborhood-averaged concentration was obtained with each percent of the street canyon volumes being occupied by vegetation for occupation fractions between 4 and 14%. The overall pattern of concentration changes relative to the tree-free situation was similar for all avenue-tree layouts. However, pronounced locally restricted decreases or increases in concentration (-87 to +1378%) occurred. The results indicate the necessity to account for existing or planned avenue-trees in neighborhood scaled is dispersion studies. Their consideration is prerequisite for reliable urban air quality assessment.

  3. Effects of gamma irradiation of Pinus banksiana Lamb. seed as expressed by M1 trees over a 10-year period

    International Nuclear Information System (INIS)

    Rudolph, T.D.

    1979-01-01

    Trees grown from seed gamma-irradiated at exposures of 150, 300, 600, 1200, 1800, 2400, 3600, 4800, 7200, 9600, 14,400 and 19,200 R, and a control were evaluated for survival, growth, flowering, and cone and seed production over a 10-yr period following seed irradiation. The LD 50 for seed germination was approximately 16,000 R, but that for tree survival was 12,600 R at six months, and 11,300 R after 10-yr. Shoot growth in surviving trees was significantly reduced at seed exposures as low as 7200 R during the first 2 yr and differences in tree height among exposure levels were still significant after 10 yr. Earliness of flowering and number of cones per tree were not significantly related to seed exposure. However, total seeds per cone and percent of filled seed differed significantly among exposures through at least the first 6 yr, indicating persistent radiation induced genetic changes. (author)

  4. Reactor safety study. An assessment of accident risks in U.S. commercial nuclear power plants. Appendix I. Accident definition and use of event trees

    International Nuclear Information System (INIS)

    1975-10-01

    Information is presented concerning accident definition and use of event trees, event tree methodology, potential accidents covered by the reactor safety study, analysis of potential accidents involving the reactor core, and analysis of potential accidents not involving the core

  5. China Report, Agriculture

    Science.gov (United States)

    1985-12-12

    than 50 percent; the breeding of valuable seafoods such as scallops, sea cucumbers and so on all showed considerable growth. Shandong’s great...over 900 yuan in economically developed areas. Grain output will average 415-429 kg per capita, edible oil and sugar,.about six kg, meat , about 23...country, trees will cover 20 percent of the land and timber output will reach 100 million cubic meters. China anticipates an annual meat output of

  6. [Effects of different patterns surface mulching on soil properties and fruit trees growth and yield in an apple orchard].

    Science.gov (United States)

    Zhang, Yi; Xie, Yong-Sheng; Hao, Ming-De; She, Xiao-Yan

    2010-02-01

    Taking a nine-year-old Fuji apple orchard in Loess Plateau as test object, this paper studied the effects of different patterns surface mulching (clean tillage, grass cover, plastic film mulch, straw mulch, and gravel mulch) on the soil properties and fruit trees growth and yield in this orchard. Grass cover induced the lowest differentiation of soil moisture profile, while gravel mulch induced the highest one. In treatment gravel mulch, the soil moisture content in apple trees root zone was the highest, which meant that there was more water available to apple trees. Surface mulching had significant effects on soil temperature, and generally resulted in a decrease in the maximum soil temperature. The exception was treatment plastic film mulch, in which, the soil temperature in summer exceeded the maximum allowable temperature for continuous root growth and physiological function. With the exception of treatment plastic film mulch, surface mulching increased the soil CO2 flux, which was the highest in treatment grass cover. Surface mulching also affected the proportion of various branch types and fruit yield. The proportion of medium-sized branches and fruit yield were the highest in treatment gravel mulch, while the fruit yield was the lowest in treatment grass cover. Factor analysis indicated that among the test surface mulching patterns, gravel mulch was most suitable for the apple orchards in gully region of Loess Plateau.

  7. Study of traffic-related pollutant removal from street canyon with trees: dispersion and deposition perspective.

    Science.gov (United States)

    Morakinyo, Tobi Eniolu; Lam, Yun Fat

    2016-11-01

    Numerical experiments involving street canyons of varying aspect ratio with traffic-induced pollutants (PM 2.5 ) and implanted trees of varying aspect ratio, leaf area index, leaf area density distribution, trunk height, tree-covered area, and tree planting pattern under different wind conditions were conducted using a computational fluid dynamics (CFD) model, ENVI-met. Various aspects of dispersion and deposition were investigated, which include the influence of various tree configurations and wind condition on dispersion within the street canyon, pollutant mass at the free stream layer and street canyon, and comparison between mass removal by surface (leaf) deposition and mass enhancement due to the presence of trees. Results revealed that concentration level was enhanced especially within pedestrian level in street canyons with trees relative to their tree-free counterparts. Additionally, we found a dependence of the magnitude of concentration increase (within pedestrian level) and decrease (above pedestrian level) due to tree configuration and wind condition. Furthermore, we realized that only ∼0.1-3 % of PM 2.5 was dispersed to the free stream layer while a larger percentage (∼97 %) remained in the canyon, regardless of its aspect ratio, prevailing wind condition, and either tree-free or with tree (of various configuration). Lastly, results indicate that pollutant removal due to deposition on leaf surfaces is potentially sufficient to counterbalance the enhancement of PM 2.5 by such trees under some tree planting scenarios and wind conditions.

  8. Disaggregating tree and grass phenology in tropical savannas

    Science.gov (United States)

    Zhou, Qiang

    Savannas are mixed tree-grass systems and as one of the world's largest biomes represent an important component of the Earth system affecting water and energy balances, carbon sequestration and biodiversity as well as supporting large human populations. Savanna vegetation structure and its distribution, however, may change because of major anthropogenic disturbances from climate change, wildfire, agriculture, and livestock production. The overstory and understory may have different water use strategies, different nutrient requirements and have different responses to fire and climate variation. The accurate measurement of the spatial distribution and structure of the overstory and understory are essential for understanding the savanna ecosystem. This project developed a workflow for separating the dynamics of the overstory and understory fractional cover in savannas at the continental scale (Australia, South America, and Africa). Previous studies have successfully separated the phenology of Australian savanna vegetation into persistent and seasonal greenness using time series decomposition, and into fractions of photosynthetic vegetation (PV), non-photosynthetic vegetation (NPV) and bare soil (BS) using linear unmixing. This study combined these methods to separate the understory and overstory signal in both the green and senescent phenological stages using remotely sensed imagery from the MODIS (MODerate resolution Imaging Spectroradiometer) sensor. The methods and parameters were adjusted based on the vegetation variation. The workflow was first tested at the Australian site. Here the PV estimates for overstory and understory showed best performance, however NPV estimates exhibited spatial variation in validation relationships. At the South American site (Cerrado), an additional method based on frequency unmixing was developed to separate green vegetation components with similar phenology. When the decomposition and frequency methods were compared, the frequency

  9. Development of canopy cover and woody vegetation biomass on reclaimed and unreclaimed post-mining sites

    Czech Academy of Sciences Publication Activity Database

    Frouz, Jan; Dvorščík, P.; Vávrová, A.; Doušová, O.; Kadochová, Štěpánka; Matějíček, L.

    2015-01-01

    Roč. 84, November (2015), s. 233-239 ISSN 0925-8574 Grant - others:GA ČR(CZ) GAP504/12/1288 Program:GA Institutional support: RVO:60077344 Keywords : aerial photographs * reclaimed sites * succession * tree biomass * woody vegetation cover Subject RIV: EH - Ecology, Behaviour Impact factor: 2.740, year: 2015

  10. Visualizing Individual Tree Differences in Tree-Ring Studies

    Directory of Open Access Journals (Sweden)

    Mario Trouillier

    2018-04-01

    Full Text Available Averaging tree-ring measurements from multiple individuals is one of the most common procedures in dendrochronology. It serves to filter out noise from individual differences between trees, such as competition, height, and micro-site effects, which ideally results in a site chronology sensitive to regional scale factors such as climate. However, the climate sensitivity of individual trees can be modulated by factors like competition, height, and nitrogen deposition, calling attention to whether average chronologies adequately assess climatic growth-control. In this study, we demonstrate four simple but effective methods to visually assess differences between individual trees. Using individual tree climate-correlations we: (1 employed jitter plots with superimposed metadata to assess potential causes for these differences; (2 plotted the frequency distributions of climate correlations over time as heat maps; (3 mapped the spatial distribution of climate sensitivity over time to assess spatio-temporal dynamics; and (4 used t-distributed Stochastic Neighborhood Embedding (t-SNE to assess which trees were generally more similar in terms of their tree-ring pattern and their correlation with climate variables. This suite of exploratory methods can indicate if individuals in tree-ring datasets respond differently to climate variability, and therefore, should not solely be explored with climate correlations of the mean population chronology.

  11. Nitrogen Nutrition of Fruit Trees to Reconcile Productivity and Environmental Concerns.

    Science.gov (United States)

    Carranca, Corina; Brunetto, Gustavo; Tagliavini, Massimo

    2018-01-10

    Although perennial fruit crops represent 1% of global agricultural land, they are of a great economic importance in world trade and in the economy of many regions. The perennial woody nature of fruit trees, their physiological stages of growth, the root distribution pattern, and the presence of herbaceous vegetation in alleys make orchard systems efficient in the use and recycling of nitrogen (N). The present paper intends to review the existing literature on N nutrition of young and mature deciduous and evergreen fruit trees with special emphasis to temperate and Mediterranean climates. There are two major sources of N contributing to vegetative tree growth and reproduction: root N uptake and internal N cycling. Optimisation of the use of external and internal N sources is important for a sustainable fruit production, as N use efficiency by young and mature fruit trees is generally lower than 55% and losses of fertilizer N may occur with the consequent economic and environmental concern. Organic alternatives to mineral N fertilizer like the application of manure, compost, mulching, and cover crops are scarcely used in perennial fruit trees, in spite of the fact that society's expectations call for more sustainable production techniques and the demand for organic fruits is increasing.

  12. Fuzzy Uncertainty Evaluation for Fault Tree Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Beom; Shim, Hyung Jin [Seoul National University, Seoul (Korea, Republic of); Jae, Moo Sung [Hanyang University, Seoul (Korea, Republic of)

    2015-05-15

    This traditional probabilistic approach can calculate relatively accurate results. However it requires a long time because of repetitive computation due to the MC method. In addition, when informative data for statistical analysis are not sufficient or some events are mainly caused by human error, the probabilistic approach may not be possible because uncertainties of these events are difficult to be expressed by probabilistic distributions. In order to reduce the computation time and quantify uncertainties of top events when basic events whose uncertainties are difficult to be expressed by probabilistic distributions exist, the fuzzy uncertainty propagation based on fuzzy set theory can be applied. In this paper, we develop a fuzzy uncertainty propagation code and apply the fault tree of the core damage accident after the large loss of coolant accident (LLOCA). The fuzzy uncertainty propagation code is implemented and tested for the fault tree of the radiation release accident. We apply this code to the fault tree of the core damage accident after the LLOCA in three cases and compare the results with those computed by the probabilistic uncertainty propagation using the MC method. The results obtained by the fuzzy uncertainty propagation can be calculated in relatively short time, covering the results obtained by the probabilistic uncertainty propagation.

  13. Histologic findings in the tracheobronchial tree of uranium miners and non-miners with lung cancer

    International Nuclear Information System (INIS)

    Auerbach, O.; Saccomanno, G.; Kuschner, M.; Brown, R.D.; Garfinkel, L.

    1978-01-01

    The remaining tissue of the tracheobronchial tree from 210 men who died from lung cancer was studied to compare the histologic alterations leading to further sites of primary cancer. These men were uranium miners matched with nonminers for age and smoking habits. In the examination of a total of 28,928 cross-sections carcinoma in situ was found in 96 percent of the miners and in 92 percent of the nonminers. The number of slides from miners showing degree 2 or 3 atypia in areas of carcinoma in situ was about double the number found from the nonminers. Although the difference was not statistically significant, 32 percent of the miners had at least one section showing early primary invasive carcinoma compared with 22 percent of the nonminers. The data indicate that the synergistic effect of the exposure to uranium dust along with cigarette smoking increases the risk of lung cancer and that in addition to a main tumor mass, other sites of tissue alterations leading to tumor development are frequently already present in the lung

  14. The role of genetics and tree improvement in southern forest productivity

    Science.gov (United States)

    Ronald C. Schmidtling; T.L. Robison; S.E. McKeand; R.J. Rousseau; H.L. Allen; B. Goldfarb

    2004-01-01

    Because of space limitations, a thorough discussion of the rich history of tree improvement in the Southeastern United States cannot be totally accomplished in this forum. However, a synopsis of key program highlights and the people who forged and directed these programs is presented, together with a discussion of current and future work. This discussion covers...

  15. The influence of tree age and microhabitat quality on the occurrence of crustose lichens associated with old oaks

    OpenAIRE

    Ranius, Thomas; Johansson, Per; Berg, Niclas; Niklasson, Mats

    2008-01-01

    Questions: How do tree age, microhabitat characteristics and epiphytic competitors affect the occurrence of crustose lichens associated with old oaks? How do microhabitat characteristics and microclimate affect the cover of competitors (bryophytes and macrolichens)? How do microhabitat characteristics cor¬relate with microclimatic variables? Location: Southeast Sweden. Methods: Eight crustose lichen species were surveyed on 165 Quercus robur trees, 17-478 years old, at three study sit...

  16. 7 CFR 762.129 - Percent of guarantee and maximum loss.

    Science.gov (United States)

    2010-01-01

    ... loss. (a) General. The percent of guarantee will not exceed 90 percent based on the credit risk to the lender and the Agency both before and after the transaction. The Agency will determine the percentage of... PLP lenders will not be less than 80 percent. (d) Maximum loss. The maximum amount the Agency will pay...

  17. Inventory and change detection of urban land cover in Illinois using Landsat Thematic Mapper data

    International Nuclear Information System (INIS)

    Cook, E.A.; Iverson, L.R.

    1991-01-01

    In order to provide information about urban forests and other vegetative land cover in Illinois cities, Landsat TM data from June 17, 1988, were classified for the Chicago metropolitan region and five urban areas of central Illinois. Ten land cover classes were identified, including three types of forestland, cropland, two grassland categories, two urban classes, water, and miscellaneous vegetation. The cities inventoried have a significantly higher proportion of forests and forested residential areas than the surrounding rural areas because of preservation measures and accruement of tree cover from landscaping. Short-term change in land cover for the Chicago region was also assessed by postclassification comparison of the 1988 data with similarly derived data from a June 3, 1985, TM scene. The largest single category of change in the six-county area was cropland to urban land use. A majority of cover loss was conversion of forested tracts to residential areas, and forest cover increase was negligible. 16 refs

  18. Influence of the prunnig of trees on the volume and distribution of the rain on the floor in dehesa ecosystem

    International Nuclear Information System (INIS)

    Mateos Rodriguez, A. B.; Schnabel, S.

    2009-01-01

    Dehesas are dominant ecosystems in the region of Extremadure (SW Spain), being Quercus species, mainly holm and cork oaks the dominant tree species. Those species undertake a very important role on the dehesa landscapes as essential elements for the adequate functioning of the systems. Among other issues, tree cover affects the spatial distribution of rainfall. (Author) 4 refs.

  19. Metal fate and partitioning in soils under bark beetle-killed trees.

    Science.gov (United States)

    Bearup, Lindsay A; Mikkelson, Kristin M; Wiley, Joseph F; Navarre-Sitchler, Alexis K; Maxwell, Reed M; Sharp, Jonathan O; McCray, John E

    2014-10-15

    Recent mountain pine beetle infestation in the Rocky Mountains of North America has killed an unprecedented acreage of pine forest, creating an opportunity to observe an active re-equilibration in response to widespread land cover perturbation. This work investigates metal mobility in beetle-impacted forests using parallel rainwater and acid leaches to estimate solid-liquid partitioning coefficients and a complete sequential extraction procedure to determine how metals are fractionated in soils under trees experiencing different phases of mortality. Geochemical model simulations analyzed in consideration with experimental data provide additional insight into the mechanisms controlling metal complexation. Metal and base-cation mobility consistently increased in soils under beetle-attacked trees relative to soil under healthy trees. Mobility increases were more pronounced on south facing slopes and more strongly correlated to pH under attacked trees than under healthy trees. Similarly, soil moisture was significantly higher under dead trees, related to the loss of transpiration and interception. Zinc and cadmium content increased in soils under dead trees relative to living trees. Cadmium increases occurred predominantly in the exchangeable fraction, indicating increased mobilization potential. Relative increases of zinc were greatest in the organic fraction, the only fraction where increases in copper were observed. Model results reveal that increased organic complexation, not changes in pH or base cation concentrations, can explain the observed differences in metal partitioning for zinc, nickel, cadmium, and copper. Predicted concentrations would be unlikely to impair human health or plant growth at these sites; however, higher exchangeable metals under beetle-killed trees relative to healthy trees suggest a possible decline in riverine ecosystem health and water quality in areas already approaching criteria limits and drinking water standards. Impairment of water

  20. Modular tree automata

    DEFF Research Database (Denmark)

    Bahr, Patrick

    2012-01-01

    Tree automata are traditionally used to study properties of tree languages and tree transformations. In this paper, we consider tree automata as the basis for modular and extensible recursion schemes. We show, using well-known techniques, how to derive from standard tree automata highly modular...