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Sample records for valley experimental forest

  1. Forest pathology and entomology at Fort Valley Experimental Forest

    Science.gov (United States)

    Brian W. Geils

    2008-01-01

    Forest pathology and entomology have been researched at Fort Valley Experimental Forest throughout its history. The pathogens and insects of particular interest are mistletoes, decay and canker fungi, rusts, bark beetles, and various defoliators. Studies on life history, biotic interactions, impacts, and control have been published and incorporated into silvicultural...

  2. Early thinning experiments established by the Fort Valley Experimental Forest

    Science.gov (United States)

    Benjamin P. De Blois; Alex. J. Finkral; Andrew J. Sanchez Meador; Margaret M. Moore

    2008-01-01

    Between 1925 and 1936, the Fort Valley Experimental Forest (FVEF) scientists initiated a study to examine a series of forest thinning experiments in second growth ponderosa pine stands in Arizona and New Mexico. These early thinning plots furnished much of the early background for the development of methods used in forest management in the Southwest. The plots ranged...

  3. Revisiting Pearson's climate and forest type studies on the Fort Valley Experimental Forest (P-53)

    Science.gov (United States)

    Joseph E. Crouse; Margaret M. Moore; Peter Z. Fule

    2008-01-01

    Five weather station sites were established in 1916 by Fort Valley personnel along an elevational gradient from the Experimental Station to near the top of the San Francisco Peaks to investigate the factors that controlled and limited forest types. The stations were located in the ponderosa pine, Douglas-fir, limber pine, Engelmann spruce, and Engelmann spruce/...

  4. Ecological restoration experiments (1992-2007) at the G.A. Pearson Natural Area, Fort Valley Experimental Forest (P-53)

    Science.gov (United States)

    Margaret M. Moore; Wallace Covington; Peter Z. Fulé; Stephen C. Hart; Thomas E. Kolb; Joy N. Mast; Stephen S. Sackett; Michael R. Wagner

    2008-01-01

    In 1992 an experiment was initiated at the G. A. Pearson Natural Area on the Fort Valley Experimental Forest to evaluate long-term ecosystem responses to two restoration treatments: thinning only and thinning with prescribed burning. Fifteen years of key findings about tree physiology, herbaceous, and ecosystem responses are presented.

  5. The Massabesic Experimental Forest

    Science.gov (United States)

    Thomas W. McConkey; Wendell E. Smith

    1958-01-01

    White pine and fire! These two - the tree and its destroyer, fire - are keys to the history and present make-up of the research program on the Massabesic Experimental Forest at Alfred, Maine. The Forest was established in the late 1930's to study the management of eastern white pine. During World War II, it was shut down, and reopened again in 1946. Then, in 1947...

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

    Energy Technology Data Exchange (ETDEWEB)

    Bossavy, J

    1962-01-01

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

  7. H.J. Andrews Experimental Forest.

    Science.gov (United States)

    Art McKee; Pamela. Druliner

    1998-01-01

    The H.J. Andrews Experimental Forest is a world renowned center for research and education about the ecology and management of forests and streams. Located about 50 miles (80 km) east of Eugene, Oregon, the Andrews Experimental Forest lies in the Blue River Ranger District of the Willamette National Forest. Established in 1948, the Experimental Forest is administered...

  8. Forest types of the "Argentino River Valley" Natural Reserve

    Directory of Open Access Journals (Sweden)

    Bagnato S

    2008-09-01

    Full Text Available Forest classification is a fundamental target for understanding forest stand dynamics and for sustainable management strategy applications. In this paper the methodological approach of forest types, already used in other Italians region, was applied for the classification of the RNO "Argentino River Valley" (southern Apennine, Italy. This study has been organized in 4 steps: 1 bibliographic analysis and collection of the acquired knowledge; 2 preliminary verification of forest types in the field; 3 description of the different units; 4 final validation of typological units. Using this approach we have characterized 9 categories and 12 forest types units. The description of each units has been filed as cards, where information of different nature is summarized and related to the organization of the typological units, to its location, to the description of the qualitative indicators (disturbances, cohort, mortality, natural dynamic tendencies, SDT, CWD etc. and quantitative indicators (dbh, average height, current annual increment, etc., to the functioning and the current management. For a better understanding of types functioning, "sylvology models" based on the "Spatial Pattern of Relative Collective Interaction" (PSICR and on the principal characteristics influencing and characterizing forest stand dynamics (availability of resources, type and frequency of disturbances, stand development, etc. have been singled out and proposed. The "forest types map" and other maps useful for the management of forest resources have been obtained. Moreover, data collected did allow to formulate several hypotheses on sustainable management.

  9. The Stephen F. Austin Experimental Forest

    Science.gov (United States)

    Cary C. Russell; Ronald E. Thill; David L. Kulhavy

    2002-01-01

    On December 14, 1944, the Seventy-Eighth United States Congress passed a bill that authorized the transfer of 2,560 acres in Nacogdoches County, Texas, to the research branch of the United States Forest Service (USFS). This land became the Stephen F. Austin Experimental Forest (SFAEF) on September 19. 1945. One of eighty-one federal experimental forests and ranges...

  10. Anthropogenic influence on forest landscape in the Khumbu valley, Nepal

    Science.gov (United States)

    Lingua, Emanuele; Garbarino, Matteo; Urbinati, Carlo; Carrer, Marco

    2013-04-01

    High altitude Himalayan regions are geo-dynamically very active and very sensitive to natural and anthropogenic disturbances due to their steep slopes, variations of precipitations with elevation and short growing periods. Nonetheless, even in this remote region human pressure is often the most important factor affecting forest landscape. In the last decades the firewood demand has increased each year between September to December. The increase in the number of tourists, mountaineering, guides, porters, carpenters, lodges lead to a peak in the use of fuelwood. In order to understand anthropogenic impacts on forest, resources landscape and stand scale dynamics were analyzed in the Sagarmatha National Park (SNP) and its Buffer Zone in the Khumbu Valley (Nepal, Eastern Himalaya). Biological and historical data sources were employed, and a multi-scale approach was adopted to capture the influence of human activities on the distribution of tree species and forest structure. Stand structure and a range of environmental variables were sampled in 197 20x20 m square plots, and land use and anthropogenic variables were derived in a GIS environment (thematic maps and IKONOS, Landsat and Terra ASTER satellite images). We used multivariate statistical analyses to relate forest structure, anthropogenic influences, land uses, and topography. Fuel wood is the prime source of energy for cooking (1480-1880 Kg/person/year) and Quercus semecarpifolia, Rhododendron arboreum and Pinus wallichiana, among the others, are the most exploited species. Due to lack of sufficient energy sources deforestation is becoming a problem in the area. This might be a major threat causing soil erosion, landslides and other natural hazards. Among the 25 species of trees that were found in the Buffer Zone Community Forests of SNP, Pinus wallichiana, Lyonia ovalifolia, Quercus semecarpifolia and Rhododendron arboreum are the dominant species. The total stand density ranged from 228 to 379 tree/ha and the

  11. Women of the Forest of the Guaporé Valley and their Interactions with the Environment

    Directory of Open Access Journals (Sweden)

    Tereza Almeida Cruz

    2010-09-01

    Full Text Available This work analyzes how the quilombola women of the Guaporé Valley, through their daily activities and their ways of life, construct their knowledge about the environment, promoting the sustainable development. The discussion related to the construction of women’s knowledge about the forest and the rivers will be done through dialogues contained in interviews describing their experiences within the forest as rubber extractors, nut collectors, fishers, and healers, revealing how they use natural resources, preserving the environment.

  12. Environment and forest regeneration in the Illinois Valley area of southwestern Oregon.

    Science.gov (United States)

    Don Minore; Joseph N. Graham; Edward W. Murray

    1984-01-01

    Multiple regression analyses were used to relate environmental factors to forest regeneration on clearcut and partial cut areas managed by the Bureau of Land Management in the Illinois Valley area southwest of Grants Pass, Oregon. Difficulty of regenerating clearcuttings at elevations between 3,000 and 4,900 feet (914 and 1 494 m) increased with increases in soil...

  13. Bichromatic Scintillometer Measurements of Sensible and Latent Heat Fluxes over a Boreal Forested Valley

    Science.gov (United States)

    Isabelle, P. E.; Nadeau, D.; Parent, A. C.; Rousseau, A. N.; Jutras, S.; Anctil, F.

    2017-12-01

    Boreal forest covers roughly 10% of the earth emerged surface, making it one of the world most common type of landscape. There is a large number of studies on the land-atmosphere exchanges of water and energy for this type of forested surfaces. However, few were located in complex terrain, and, to the best of our knowledge, none have looked at continuous regional scale fluxes. Scintillometry is a powerful tool that allows such measurements, but is usually used over flat homogeneous terrain due to its dependency on Monin-Obukhov Similarity Theory. However, some recent studies have applied this method over slopes, measuring fluxes comparable to those using the eddy covariance method. Still, more experiments are needed using scintillometry over sloped surfaces. This study presents bichromatic scintillometer measurements of sensible and latent heat fluxes over a boreal-forested valley. The field site is located in the Montmorency Forest, Québec, Canada (47°17'N; 71°10'W). The instrumented valley is surrounded by ridges at 900 m elevation, with the bottom stream at 785 m, and follows a 300-120° azimuth coinciding with the two main wind direction (up and down-valley, respectively). Vegetation mostly includes balsam firs 6-10 m tall, creating a rough but homogeneous surface. Scintillometer transmitters and receivers are installed on top of the ridges enclosing the valley, making the path 1.35 km long and its effective height 70-m tall. The setup includes a large aperture and a micro-wave scintillometer with crossing paths allowing the use of the bichromatic method. Measurement are taken continuously from August to October 2017. Scintillometer fluxes are compared with those measured by a 15-m eddy covariance tower located 100 m west of the measurement path, on the southern slope of the valley. Net radiation is also measured to assess energy budget closure over the valley. The setup allows us to test the limits of applicability of scintillometer measurements, especially

  14. Hydrological processes of reference watersheds in Experimental Forests, USA

    Science.gov (United States)

    Devendra Amatya; John Campbell; Pete Wohlgemuth; Kelly Elder; Stephen Sebestyen; Sherri Johnson; Elizabeth Keppeler; Mary Beth Adams; Peter Caldwell; D. Misra

    2016-01-01

    Long-term research at small, gauged, forested watersheds within the USDA Forest Service, Experimental Forest and Range network (USDA-EFR) has contributed substantially to our current understanding of relationships between forests and streamflow (Vose et al., 2014). Many of these watershed studies were established in the early to mid-20th century and have been used to...

  15. Role of the USDA Forest Service experimental forest: an extension point of view

    Science.gov (United States)

    Eric L. Taylor; C. Darwin Foster; Diomy Zamora

    2013-01-01

    The expansive network of experimental forests (EF) facilitated by the U.S. Forest Service (Forest Service) encompasses a fairly complete representation of the forest ecotypes in the nation. The network, 101 years old this year (2009), has provided researchers with a wealth of long-term data on silviculture, watershed protection, and restoration. However, our nation’s...

  16. Hydrologic influences of forest vegetation in a changing world: Learning from Forest Service experimental forests, ranges, and watersheds

    Science.gov (United States)

    Thomas E. Lisle; Mary Beth Adams; Leslie M. Reid; Kelly Elder

    2010-01-01

    The importance of forests in providing reliable sources of clean water cannot be underestimated. Therefore, there is a pressing need to understand how hydrologic systems function in forested ecosystems, in response to a variety of traditional and novel stressors and environments. Long-term watershed research on Experimental Forests and Ranges (EFRs) of the Forest...

  17. Outlook for Mississippi Alluvial Valley forests: a subregional report from the Southern Forest Futures Project

    Science.gov (United States)

    Emile S. Gardiner

    2015-01-01

    The Mississippi Alluvial Valley, which can be broadly subdivided into the Holocene Deposits section and the Deltaic Plain section, is a 24.9-million-acre area generally approximating the alluvial floodplain and delta of the lower Mississippi River. Its robust agricultural economy is maintained by a largely rural population, and recreational resources draw high...

  18. Compact cluster growth on the half-plane: forest fires in a valley

    CERN Document Server

    Kearney, M J

    2003-01-01

    A two-parameter model on a directed lattice is introduced to represent the growth and spread of clusters on the half-plane. The model exhibits a phase transition in the compact directed percolation universality class between a state where clusters are finite with probability one and a state where clusters are infinite with non-zero probability. In the finite regime, exact expressions are given for the mean perimeter length and area of the generated clusters for a variety of different boundary conditions. An illustrative example is considered, namely a forest fire spreading before a prevailing wind along the floor and sides of an idealized valley.

  19. Research related to roads in USDA experimental forests [Chapter 16

    Science.gov (United States)

    W. J. Elliot; P. J. Edwards; R. B. Foltz

    2014-01-01

    Forest roads are essential in experimental forests and rangelands (EFRs) to allow researchers and the public access to research sites and for fire suppression, timber extraction, and fuel management. Sediment from roads can adversely impact watershed health. Since the 1930s, the design and management of forest roads has addressed both access issues and watershed health...

  20. Relationship between Forest Color Characteristics and Scenic Beauty: Case Study Analyzing Pictures of Mountainous Forests at Sloped Positions in Jiuzhai Valley, China

    Directory of Open Access Journals (Sweden)

    Zhe Zhang

    2017-02-01

    Full Text Available Forests are important place for outdoor recreation and scenery appreciation. So in order to better meet the needs of the public, forest appreciation has received increasing attention from foresters in recent years. However, related research is still limited. Therefore, this paper seeks to examine the relationship between forest colors (measured by specific elements and spatial indices of color and Scenic Beauty Estimation values. We researched Jiuzhai Valley in China by selecting 104 pictures to determine the scenic beauty estimation values of forests in a mountainous region. Quantitative color elements were extracted by programming on Matlab, and spatial indices of color patches were extracted by ArcGIS and FRAGSTATS. A total of 23 indices were obtained to explain the color characteristics of each forest picture. The results showed that the yellow and red colors were the main mutable colors of Jiuzhai Valley in autumn, but the color patches index had no significant change over time in that season. After partial correlation analysis, principal component analysis, and cluster analysis, we found that 14 color elements, eight color patch factors and six particular indices had an effect on the SBE values, which can then be used to efficiently measure and enhance the forest color beauty of Jiuzhai Valley.

  1. A visual progression of the Fort Valley Restoration Project treatments using remotely sensed imagery (P-53)

    Science.gov (United States)

    Joseph E. Crouse; Peter Z. Fule

    2008-01-01

    The landscape surrounding the Fort Valley Experimental Forest in northern Arizona has changed dramatically in the past decade due to the Fort Valley Restoration Project, a collaboration between the Greater Flagstaff Forest Partnership, Coconino National Forest, and Rocky Mountain Research Station. Severe wildfires in 1996 sparked community concern to start restoration...

  2. Behavioral assumptions of conservation policy: conserving oak habitat on family-forest land in the Willamette Valley, Oregon

    Science.gov (United States)

    A. Paige Fischer; John C. Bliss

    2008-01-01

    Designing policies that harness the motivations of landowners is essential for conserving threatened habitats on private lands. Our goal was to understand how to apply ethnographic information about family-forest owners to the design of conservation policy for Oregon white oak (Quercus garryana) in the Willamette Valley, Oregon (U.S.A.). We examined...

  3. The Illumination Model of the Valley Based on the Diffuse Reflect of Forest

    Directory of Open Access Journals (Sweden)

    He Guoliang

    2016-01-01

    Full Text Available In this paper, models are build to evaluate the impact of the forest on the valley’s illumination. Based on the assumes that all the light reach the ground comes from the diffuse reflection which comes from the sun directly and from the diffuse reflection of other points, One model is build to consider the impact of time and latitude on the direction of the sunlight. So we can get the direction of the sunlight at different time and latitude through the model. Besides, this paper develops a illumination model to evaluate the intensity of illumination of the ground. Combining the models above, this paper get a complete model which can not only evaluate the overall light intensity of the valley but also convert the light intensity to the intensity of illumination. Simulation of the intensity illumination of some basic terrains and finally gives a comprehensive results which is practical and close to the common sense.

  4. Vascular flora and macroscopic fauna on the Fernow Experimental Forest

    Science.gov (United States)

    Darlene M. Madarish; Jane L. Rodrigue; Mary Beth Adams

    2002-01-01

    This report is the first comprehensive inventory of the vascular flora and macroscopic fauna known to occur within the Fernow Experimental Forest in north-central West Virignia. The compendium is based on information obtained from previous surveys, current research, and the personal observations of USDA Forest Service personnel and independent scientists. More than 750...

  5. Silvicultural activities in Pringle Falls Experimental Forest, Central Oregon

    Science.gov (United States)

    Andrew Youngblood; Kim Johnson; Jim Schlaich; Boyd Wickman

    2004-01-01

    Pringle Falls Experimental Forest has been a center for research in ponderosa pine forests east of the crest of the Cascade Range since 1931. Long-term research facilities, sites, and future research opportunities are currently at risk from stand-replacement wildfire because of changes in stand structure resulting from past fire exclusion. At the same time, many of the...

  6. Experimental forests and ranges : 100 years of research success stories

    Science.gov (United States)

    Gail Wells; Deborah Hayes; Katrina Krause; Ann Bartuska; Susan LeVan-Green; Jim Anderson; Tivoli Gough; Mary Adams; Thomas Schuler; Randy Kolka; Steve Sebestyen; Laura Kenefic; John Brissette; Susan Stout; Keith Kanoti; Fred Swanson; Sarah Greene; Margaret Herring; Martin Ritchie; Carl Skinner; Tom Lisle; Elizabeth Keppeler; Leslie Reid; Peter Wohlegemuth; Stanley Kitchen; Ward McCaughey; Jim Guldin; Don Bragg; Michael Shelton; David Loftis; Cathryn Greenberg; Julia Murphy

    2009-01-01

    In 2008, Forest Service Research and Development celebrated the Centennial Anniversary of these Experimental Forests and Ranges. This publication celebrates the many scientists who over the course of decades conducted the long-term studies that began and are continuing to shed light on important natural resource issues. Story suggestions were solicited from the...

  7. Diversity and primary productivity of hill beech forests from Doftana Valley (Romanian Subcarpathians

    Directory of Open Access Journals (Sweden)

    Mihaela Paucã-Comãnescu

    2009-11-01

    Full Text Available The hill beech forests cover most of the woody area in the Doftana Valley. The present study refers, for the first time, to two beech forests typical to this belt, which belong to the phytocoenological associations Epipactieto-Fagetum (Resmeritã,1972, in the Lunca Mare area, and Hieracio rotundati-Fagetum (Vida 1983, Täuber 1987 in the Sotrile area, from floristic, structural, biomass and necromassaccumulation point of view, within the framework of the vertical structure of biocoenosis.The limestone substratum, occasionally with small outcrops in the first beech forest, differs chiefly through the pH levels (6.34-5.67 from the siliceous substratum (pH 5.11-4.36 in the second beech forest. The layer of trees is dominated by Fagus sylvatica in both forests; this species is associated with Cerasus avium (4.5%,Acer pseudoplatanus (2% and Sorbus torminalis (2% in the first beech forest, and is monodominant in the second. Although the forest underwent selective cuts, more intense in the Lunca Mare area, the aboveground ligneous biomass reaches nowadays 222 t/ha in the Lunca Mare area compared to only 163 t/ha in the Sotrile area; theaverage height is 28.8±2.49 m and 23.7±1.12 m, respectively, and the diameter is 33.30±7.9 cm and 31.60±6.28 cm, respectively. The species of macrofungi, not very numerous during the study because of scarce precipitations (6 and 7 species, respectively,are predominant on the rhytidoma trees in the beech forest rooted on the limestone ground; in the Sotrile beech forest they are joined by mycorrhizal and parasite species. The layer of shrub is underdeveloped. The herbaceous layer is discontinuous, and includes, along herbs, small plants and saplings belonging to the ligneous species and to liana Hedera helix. The maximal value of the aboveground biomass of thelayer is 317 kg/ha DM in the Lunca Mare area and 235 kg /ha DM in the Sotrile area.Bryophyta is present in large quantities, especially in the ªotrile area

  8. US Forest Service experimental forests and ranges: an untapped resource for social science

    Science.gov (United States)

    Susan Charnley; Lee K. Cerveny

    2011-01-01

    For a century, US Forest Service experimental forests and ranges (EFRs) have been a resource for scientists conducting long-term research relating to forestry and range management social science research has been limited, despite the history of occupation and current use of these sites for activities ranging from resource extraction and recreation to public education....

  9. Tree growth and recruitment in a leveed floodplain forest in the Mississippi River Alluvial Valley, USA

    Science.gov (United States)

    Gee, Hugo K.W.; King, Sammy L.; Keim, Richard F.

    2014-01-01

    Flooding is a defining disturbance in floodplain forests affecting seed germination, seedling establishment, and tree growth. Globally, flood control, including artificial levees, dams, and channelization has altered flood regimes in floodplains. However, a paucity of data are available in regards to the long-term effects of levees on stand establishment and tree growth in floodplain forests. In this study, we used dendrochronological techniques to reconstruct tree recruitment and tree growth over a 90-year period at three stands within a ring levee in the Mississippi River Alluvial Valley (MAV) and to evaluate whether recruitment patterns and tree growth changed following levee construction. We hypothesized that: (1) sugarberry is increasing in dominance and overcup oak (Quercus lyrata) is becoming less dominant since the levee, and that changes in hydrology are playing a greater role than canopy disturbance in these changes in species dominance; and (2) that overcup oak growth has declined following construction of the levee and cessation of overbank flooding whereas that of sugarberry has increased. Recruitment patterns shifted from flood-tolerant overcup oak to flood-intolerant sugarberry (Celtis laevigata) after levee construction. None of the 122 sugarberry trees cored in this study established prior to the levee, but it was the most common species established after the levee. The mechanisms behind the compositional change are unknown, however, the cosmopolitan distribution of overcup oak during the pre-levee period and sugarberry during the post-levee period, the lack of sugarberry establishment in the pre-levee period, and the confinement of overcup oak regeneration to the lowest areas in each stand after harvest in the post-levee period indicate that species-specific responses to flooding and light availability are forcing recruitment patterns. Overcup oak growth was also affected by levee construction, but in contrast to our hypothesis, growth actually

  10. Diversity and primary productivity of hill beech forests from Doftana Valley (Romanian Subcarpathians

    Directory of Open Access Journals (Sweden)

    Mihaela Paucã-Comãnescu

    2009-12-01

    Full Text Available The hill beech forests cover most of the woody area in the Doftana Valley. The present study refers, for the first time, to two beech forests typical to this belt, which belong to the phytocoenological associations Epipactieto-Fagetum (Resmeriţă, 1972, in the Lunca Mare area, and Hieracio rotundati-Fagetum (Vida 1983, Täuber 1987 in the Sotrile area, from floristic, structural, biomass and necromass accumulation point of view, within the framework of the vertical structure of biocoenosis. The limestone substratum, occasionally with small outcrops in the first beech forest, differs chiefly through the pH levels (6.34-5.67 from the siliceous substratum (pH 5.11-4.36 in the second beech forest. The layer of trees is dominated by Fagus sylvatica in both forests; this species is associated with Cerasus avium (4.5%, Acer pseudoplatanus (2% and Sorbus torminalis (2% in the first beech forest, and is monodominant in the second. Although the forest underwent selective cuts, more intense in the Lunca Mare area, the aboveground ligneous biomass reaches nowadays 222 t/ha in the Lunca Mare area compared to only 163 t/ha in the Sotrile area; the average height is 28.8ą2.49 m and 23.7ą1.12 m, respectively, and the diameter is 33.30ą7.9 cm and 31.60ą6.28 cm, respectively. The species of macrofungi, not very numerous during the study because of scarce precipitations (6 and 7 species, respectively, are predominant on the rhytidoma trees in the beech forest rooted on the limestone ground; in the Sotrile beech forest they are joined by mycorrhizal and parasite species. The layer of shrub is underdeveloped. The herbaceous layer is discontinuous, and includes, along herbs, small plants and saplings belonging to the ligneous species and to liana Hedera helix. The maximal value of the aboveground biomass of the layer is 317 kg/ha DM in the Lunca Mare area and 235 kg /ha DM in the Sotrile area. Bryophyta is present in large quantities, especially in the Sotrile

  11. Opening remarks for the Fort Valley Centennial Celebration

    Science.gov (United States)

    G. Sam Foster

    2008-01-01

    The Rocky Mountain Research Station recognizes and values the contributions of our scientists and collaborators for their work over the past century at Fort Valley Experimental Forest. With the help of our partners and collaborators, Rocky Mountain Research Station is working to improve coordination across its research Program Areas and Experimental Forests and Ranges...

  12. Opening remarks for the Fort Valley Centennial Celebration (P-53)

    Science.gov (United States)

    G. Sam Foster

    2008-01-01

    The Rocky Mountain Research Station recognizes and values the contributions of our scientists and collaborators for their work over the past century at Fort Valley Experimental Forest. With the help of our partners and collaborators, Rocky Mountain Research Station is working to improve coordination across its research Program Areas and Experimental Forests and Ranges...

  13. Fort Valley studies: A natural laboratory for research and education

    Science.gov (United States)

    Brian W. Geils

    2008-01-01

    Drought, wildfire, extinction, and invasive species are considered serious threats to the health of our forests. Although these issues have global connections, we most readily see their consequences locally and attempt to respond with management based on science. For 100 years, the Fort Valley Experimental Forest (FVEF) has provided educational and experimental support...

  14. Some observations on precipitation measurement on forested experimental watersheds

    Science.gov (United States)

    Raymond E. Leonard; Kenneth G. Reinhart

    1963-01-01

    Measurement of precipitation on forested experimental watersheds presents difficulties other than those associated with access to and from the gages in all kinds of weather. For instance, the tree canopy must be cleared above the gage. The accepted practice of keeping an unobstructed sky view of 45" around the gage involves considerable tree cutting. On a level...

  15. Checklist of vertebrate animals of the Cascade Head Experimental Forest.

    Science.gov (United States)

    Chris Maser; Jerry F. Franklin

    1974-01-01

    Three months, April and August 1971 and August 1972, were spent studying the vertebrate fauna of Cascade Head Experimental Forest. The resulting annotated checklist includes 9 amphibians, 2 reptiles, 35 birds, and 40 mammals. A standardized animal habitat classification is presented in an effort to correlate the vertebrates in some meaningful way to their environment...

  16. A network of experimental forests and ranges: Providing soil solutions for a changing world

    Science.gov (United States)

    Mary Beth. Adams

    2010-01-01

    The network of experimental forests and ranges of the USDA Forest Service represents significant opportunities to provide soil solutions to critical issues of a changing world. This network of 81 experimental forests and ranges encompasses broad geographic, biological, climatic and physical scales, and includes long-term data sets, and long-term experimental...

  17. Whole-ecosystem experimental manipulations of tropical forests

    OpenAIRE

    Fayle, Tom M; Turner, Edgar Clive; Basset, Yves; Ewers, Robert M; Reynolds, Glen; Novotny, Vojtech

    2015-01-01

    Tropical forests are highly diverse systems involving extraordinary numbers of interactions between species, with each species responding in a different way to the abiotic environment. Understanding how these systems function and predicting how they respond to anthropogenic global change is extremely challenging. We argue for the necessity of ‘whole-ecosystem’ experimental manipulations, in which the entire ecosystem is targeted, either to reveal the functioning of the...

  18. Examining relationship between environmental gradients and Lesser Himalyan forest vegetation of Nikyal valley, Azad Jammu and Kashmir using ordination analysis.

    Science.gov (United States)

    Amjad, Muhammad Shoaib; Arshad, Muhammad; Rashid, Audil; Chaudhari, Sunbal Khalil; Malik, Nafeesa Zahid; Fatima, Sammer; Akrim, Faraz

    2014-09-01

    To report the relationship of vegetation structure and environmental gradient and physiochemical properties of soil at Nikyal valley, Azad Jammu and Kashmir . A survey of natural vegetation and soil of Nikyal valley was undertaken. Phytosociological survey was conducted by using Braun-Blanquet's approach. The study also investigated the vegetation structure and its relationship with altitude and edaphic factors. The floristic data was analyzed by cluster anlaysis, detrended correspondence analysis and canonical correspondence analysis using CANACOO 5.0. A total of 110 plant species and 13 stands were merged into five major associations as dema rcated by cluster analysis and detrended correspondence analysis. The associations were Olea-Pinus-Themeda association, Myrsine-Rhus-Quercus association, Quercus-Rubus-Pinus association and Quercus association. Soil organic matter, saturation, pH and altitude play the major role in distribution of species. The variation in vegetation structure is controlled by the altitudinal gradient and physiochemical properties of soil. These results indicate a deteriorated forest structure and reduced regeneration pattern, demanding immediate attention of forest management authorities. Copyright © 2014 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

    Thurston, E; Reader, R J

    2001-03-01

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

  20. Evolution of soil, ecosystem, and critical zone research at the USDA FS Calhoun Experimental Forest

    Science.gov (United States)

    Daniel deB. Richter; Allan R. Bacon; Sharon A. Billings; Dan Binkley; Marilyn Buford; Mac Callaham; Amy E. Curry; Ryan L. Fimmen; A. Stuart Grandy; Paul R. Heine; Michael Hofmockel; Jason A. Jackson; Elisabeth LeMaster; Jianwei Li; Daniel Markewitz; Megan L. Mobley; Mary W. Morrison; Michael S. Strickland; Thomas Waldrop; Carol G. Wells

    2015-01-01

    The US Department of Agriculture (USDA) Forest Service Calhoun Experimental Forest was organized in 1947 on the southern Piedmont to engage in research that today is called restoration ecology, to improve soils, forests, and watersheds in a region that had been severely degraded by nearly 150 years farming. Today, this 2,050-ha research forest is managed by the Sumter...

  1. Long-term flow dynamics of three coastal experimental forested watersheds

    Science.gov (United States)

    Devendra M. Amatya; Artur Radecki-Pawlik

    2005-01-01

    Three 1st2nd, and 3rd order experimental forested watersheds located within Francis Marion National Forest in Coastal South Carolina were monitored for rainfall and stream outflows. These watersheds were WS80, a pine-hardwood forest (206 ha); WS79 a predominantly pine forest (500 ha); and WS78, a...

  2. An annotated bibliography of scientific literature on research and management activities conducted in Coram Experimental Forest

    Science.gov (United States)

    Ilana Abrahamson; Katie Lyon

    2012-01-01

    The Coram Experimental Forest represents western larch-mixed conifer forests of the Northern Rockies. Western larch research was centered at Coram Experimental Forest (CEF) to provide a scientific basis to regenerate and grow this important and valuable species. For example, the long-term silvicultural studies installed at CEF are allowing researchers and managers to...

  3. Human impacts on fire occurrence: a case study of hundred years of forest fires in a dry alpine valley in Switzerland

    NARCIS (Netherlands)

    Zumbrunnen, T.; Menéndez, P.; Bugmann, H.; Conedera, M.; Gimmi, U.; Bürgi, M.

    2012-01-01

    Forest fire regimes are sensitive to alterations of climate, fuel load, and ignition sources. We investigated the impact of human activities and climate on fire occurrence in a dry continental valley of the Swiss Alps (Valais) by relating fire occurrence to population and road density, biomass

  4. [Experimental study on acid mine drainage treatment using mine tailings of Xiangsi Valley, Tongling, China].

    Science.gov (United States)

    Zhang, Nan; Chen, Tian-Hu; Zhou, Yue-Fei; Li, Shao-Jie; Jin, Jie; Wang, Yan-Ming

    2012-04-01

    Mine tailings in Xiangsi Valley, Tongling, China, is a typical skarn-type tailing with high contents of carbonates. This study designed dynamic leaching experiments to investigate the efficiency of this tailing under the acid mine drainage treatment. During 80 d trial period, the physical and chemical properties of influents were fixed and the effluents were monitored. After the trial, the speciation of Fe, Cu and Zn in solid was analyzed. The results showed that during the trial period, pH value maintained above 7.5. Moreover, the concentrations of Cu, Zn, Fe ions in effluents kept below 0.1, 0.4 and 1 mg x L(-1), respectively. In addition, the permeability coefficient of experimental column kept decreasing during the experimental period (from 0.23 cm x s(-1) to 0.10 cm x s(-1)). Five-step sequential extraction method was employed to study the distribution of elements at different depths. The results showed that Cu2+, Zn2+ were removed mainly through sorption and precipitation. This study indicates that Tongling skarn mine tailings have strong acid neutralization as well as heavy metal binding capacities. Therefore, the authors suggest that this mine tailing, which used to be waste, has a potential in AMD control and treatment.

  5. Primary forest dynamics in lowland dipterocarp forest at Danum Valley, Sabah, Malaysia, and the role of the understorey.

    Science.gov (United States)

    Newbery, D M; Kennedy, D N; Petol, G H; Madani, L; Ridsdale, C E

    1999-11-29

    Changes in species composition in two 4-ha plots of lowland dipterocarp rainforest at Danum, Sabah, were measured over ten years (1986-1996) for trees > or = 10 cm girth at breast height (gbh). Each included a lower-slope to ridge gradient. The period lay between two drought events of moderate intensity but the forest showed no large lasting responses, suggesting that its species were well adapted to this regime. Mortality and recruitment rates were not unusual in global or regional comparisons. The forest continued to aggrade from its relatively (for Sabah) low basal area in 1986 and, together with the very open upper canopy structure and an abundance of lianas, this suggests a forest in a late stage of recovery from a major disturbance, yet one continually affected by smaller recent setbacks. Mortality and recruitment rates were not related to population size in 1986, but across subplots recruitment was positively correlated with the density and basal area of small trees (10-change in mortality with increasing gbh: in the former it increased, in the latter it decreased. Forest processes are centred on this understorey quasi-stratum. The two replicate plots showed a high correspondence in the mortality, recruitment, population changes and growth rates of small trees for the 49 most abundant species in common to both. Overstorey species had higher rgrs than understorey ones, but both showed considerable ranges in mortality and recruitment rates. The supposed trade-off in traits, viz slower rgr, shade tolerance and lower population turnover in the understorey group versus faster potential growth rate, high light responsiveness and high turnover in the overstorey group, was only partly met, as some understorey species were also very dynamic. The forest at Danum, under such a disturbance-recovery regime, can be viewed as having a dynamic equilibrium in functional and structural terms. A second trade-off in shade-tolerance versus drought-tolerance is suggested for

  6. A baseline assessment of forest composition, structure, and health in the Hawai‘i experimental tropical forests

    Science.gov (United States)

    Robert R. Pattison; Andrew N. Gray; Lori. Tango

    2015-01-01

    The US Forest Service’s Forest Inventory and Analysis (FIA) Program of the Pacific Northwest (PNW) Research Station has been working in the Hawaiian islands since 2010. During this time they have installed a base grid of field plots across all of the Hawaiian Islands and an intensified sample of two experimental forests, the Laupāhoehoe and Pu‘u Wa‘awa‘a units of the...

  7. Experimental transmission of West Nile Virus and Rift Valley Fever Virus by Culex pipiens from Lebanon.

    Directory of Open Access Journals (Sweden)

    Renée Zakhia

    2018-01-01

    Full Text Available West Nile virus (WNV and Rift Valley fever virus (RVFV are two emerging arboviruses transmitted by Culex pipiens species that includes two biotypes: pipiens and molestus. In Lebanon, human cases caused by WNV and RVFV have never been reported. However, the introduction of these viruses in the country is likely to occur through the migratory birds and animal trades. In this study, we evaluated the ability of Cx. pipiens, a predominant mosquito species in urban and rural regions in Lebanon, to transmit WNV and RVFV. Culex egg rafts were collected in the West Bekaa district, east of Lebanon and adult females of Cx. pipiens were experimentally infected with WNV and RVFV Clone 13 strain at titers of 1.6×108 and 1.33×107 plaque forming units (PFU/mL, respectively. We estimated viral infection, dissemination and transmission at 3, 7, 14 and 19 days post infection (dpi. Results showed that infection was higher for WNV than for RVFV from 3 dpi to 19 dpi. Viral dissemination and transmission started from 3 dpi for WNV; and only from 19 dpi for RVFV. Moreover, Cx. pipiens were able to excrete in saliva a higher number of viral particles of WNV (1028 ± 405 PFU/saliva at 19 dpi than RVFV (42 PFU/saliva at 19 dpi. Cx. pipiens from Lebanon are efficient experimental vectors of WNV and to a lower extent, RVFV. These findings should stimulate local authorities to establish an active entomological surveillance in addition to animal surveys for both viruses in the country.

  8. Study of Z > 18 elements concentration in tree rings from surroundings forests of the Mexico Valley using external beam PIXE

    International Nuclear Information System (INIS)

    Calva-Vazquez, G.; Razo-Angel, G.; Rodriguez-Fernandez, L.; Ruvalcaba-Sil, J.L.

    2006-01-01

    The concentration of elements with Z > 18 is measured in tree rings from forests at the surroundings of the Mexico Valley: El Chico National Park (ECP) and Desierto de los Leones National Park (DLP). The analysis was done by simultaneous PIXE-RBS using an external proton beam on tree rings of Pine and Sacred fir (species Pinus montezumae and Abies religiosa, respectively). This study provides information about the elemental concentration in trees of those parks during the years from 1965 to 2003. Typical elements such as K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br, Sr and Pb were detected using PIXE technique while the wood matrix composition (mainly C and O) was determined by RBS. In general, elemental contents present large variations but concentrations oscillate around the mean value during this period of time. Nevertheless, the measurements showed some trends for Fe and Zn in the tree-rings elemental composition that may be correlated to recent volcanic activities in the region. The low Mn contents indicate soil acidification in DLP from 1968 and the forest decline in ECP during the last 15 years

  9. Vegetation and Ecological Characteristics of Mixed-Conifer and Red Fir Forests at the Teakettle Experimental Forest

    Science.gov (United States)

    Malcolm North; Brian Oakley; Jiquan Chen; Heather Erickson; Andrew Gray; Antonio Izzo; Dale Johnson; Siyan Ma; Jim Marra; Marc Meyer; Kathryn Purcell; Tom Rambo; Dave Rizzo; Brent Roath; Tim. Schowalter

    2002-01-01

    Detailed analysis of mixed-conifer and red fir forests were made from extensive, large vegetation sampling, systematically conducted throughout the Teakettle Experimental Forest. Mixed conifer is characterized by distinct patch conditions of closed-canopy tree clusters, persistent gaps and shrub thickets. This heterogeneous spatial structure provides contrasting...

  10. US Forest Service Experimental Forests and Ranges Network: a continental research platform for catchment-scale research

    Science.gov (United States)

    Daniel Neary; Deborah Hayes; Lindsey Rustad; James Vose; Gerald Gottfried; Stephen Sebesteyn; Sherri Johnson; Fred Swanson; Mary Adams

    2012-01-01

    The US Forest Service initiated its catchment research program in 1909 with the first paired catchment study at Wagon Wheel Gap, Colorado, USA. It has since developed the Experimental Forests and Ranges Network, with over 80 long-term research study sites located across the contiguous USA, Alaska, Hawaii, and the Caribbean. This network provides a unique, powerful...

  11. Avian studies and research opportunities in the Luquillo Experimental Forest: a tropical rain forest in Puerto Rico

    Science.gov (United States)

    Joseph Wunderle, Jr; Wayne J. Arendt

    2011-01-01

    The Luquillo Experimental Forest (LEF) located on the Caribbean island of Puerto Rico has a rich history of ecological research, including a variety of avian studies, and is one of the most active ecological research sites in the Neotropics. The LEF spans an elevational range from 100 to 1075mover which five life zones and four forest types are found in a warm, humid...

  12. Evaporation from a tropical rain forest, Luquillo Experimental Forest, eastern Puerto Rico

    Science.gov (United States)

    Schellekens, J.; Bruijnzeel, L. A.; Scatena, F. N.; Bink, N. J.; Holwerda, F.

    2000-08-01

    Evaporation losses from a watertight 6.34 ha rain forest catchment under wet maritime tropical conditions in the Luquillo Experimental Forest, Puerto Rico, were determined using complementary hydrological and micrometeorological techniques during 1996 and 1997. At 6.6 mm d-1 for 1996 and 6.0 mm d-1 for 1997, the average evapotranspiration (ET) of the forest is exceptionally high. Rainfall interception (Ei), as evaluated from weekly throughfall measurements and an average stemflow fraction of 2.3%, accounted for much (62-74%) of the ET at 4.9 mm d-1 in 1996 and 3.7 mm d-1 in 1997. Average transpiration rates (Et) according to a combination of the temperature fluctuation method and the Penman-Monteith equation were modest at 2.2 mm d-1 and 2.4 mm d-1 in 1996 and 1997, respectively. Both estimates compared reasonably well with the water-budget-based estimates (ET - Ei) of 1.7 mm d-1 and 2.2 mm d-1. Inferred rates of wet canopy evaporation were roughly 4 to 5 times those predicted by the Penman-Monteith equation, with nighttime rates very similar to daytime rates, suggesting radiant energy is not the dominant controlling factor. A combination of advected energy from the nearby Atlantic Ocean, low aerodynamic resistance, plus frequent low-intensity rain is thought to be the most likely explanation of the observed discrepancy between measured and estimated Ei.

  13. Development of watershed hydrologic research at Santee Experimental Forest, coastal South Carolina

    Science.gov (United States)

    Devendra Amatya; Carl Trettin

    2007-01-01

    Managing forested wetland landscapes for water quality improvement and productivity requires a detailed understanding of functional linkages between ecohydrological processes and management practices. Watershed studies are being conducted at USDA Forest Service Santee Experimental Forest, South Carolina, to understand the fundamental hydrologic and biogeochemical...

  14. Long-term trends from ecosystem research at the Hubbard Brook Experimental Forest

    Science.gov (United States)

    John L. Campbell; Charles T. Driscoll; Christopher Eagar; Gene E. Likens; Thomas G. Siccama; Chris E. Johnson; Timothy J. Fahey; Steven P. Hamburg; Richard T. Holmes; Amey S. Bailey; Donald C. Buso

    2007-01-01

    Summarizes 52 years of collaborative, long-term research conducted at the Hubbard Brook (NH) Experimental Forest on ecosystem response to disturbances such as air pollution, climate change, forest disturbance, and forest management practices. Also provides explanations of some of the trends and lists references from scientific literature for further reading.

  15. A century of avian research on USFS Experimental Forests and Ranges: Introduction to the special section on long-term avian research on Experimental Forests and Ranges

    Science.gov (United States)

    Monica Tomosy; Scott H. Stoleson; David I. King

    2011-01-01

    In August of 2009 a symposium was convened at the 127th Stated Meeting of the American Ornithologist's Union in Philadelphia, Pennsylvania to commemorate the 100th anniversary of the nationwide system of Experimental Forests and Ranges (EFRs) established by the US Forest Service in 1909. Fifteen scientists from across the United States and the Caribbean gathered...

  16. The experimental design of the Missouri Ozark Forest Ecosystem Project

    Science.gov (United States)

    Steven L. Sheriff; Shuoqiong. He

    1997-01-01

    The Missouri Ozark Forest Ecosystem Project (MOFEP) is an experiment that examines the effects of three forest management practices on the forest community. MOFEP is designed as a randomized complete block design using nine sites divided into three blocks. Treatments of uneven-aged, even-aged, and no-harvest management were randomly assigned to sites within each block...

  17. Fifty years of watershed research on the Fernow Experimental Forest, WV: effects of forest management and air pollution on hardwood forests

    Science.gov (United States)

    M.B. Adams; P.J. Edwards; J.N. Kochenderfer; F. Wood

    2004-01-01

    In 1951, stream gaging was begun on five small headwater catchments on the Fernow Experimental Forest in West Virginia, to study the effects of forest management activities, particularly timber harvesting, on water yield and quality. Results from these watersheds, and others gaged more recently, have shown that annual water yields increase in proportion to the basal...

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

    Science.gov (United States)

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

    2012-01-01

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

  19. Sixty years of research, 60 years of data: long-term US Forest Service data management on the Penobscot Experimental Forest

    Science.gov (United States)

    Matthew B. Russell; Spencer R. Meyer; John C. Brissette; Laura Kenefic

    2014-01-01

    The U.S. Department of Agriculture, Forest Service silvicultural experiment on the Penobscot Experimental Forest (PEF) in Maine represents 60 years of research in the northern conifer and mixedwood forests of the Acadian Forest Region. The objective of this data management effort, which began in 2008, was to compile, organize, and archive research data collected in the...

  20. The Kane Experimental Forest carbon inventory: Carbon reporting with FVS

    Science.gov (United States)

    Coeli Hoover

    2008-01-01

    As the number of state and regional climate change agreements grows, so does the need to assess the carbon implications of planned forest management actions. At the operational level, producing detailed stock estimates for the primary carbon pools becomes time-consuming and cumbersome. Carbon reporting functionality has been fully integrated within the Forest...

  1. Experimental data developed to support the selection of a treatment process for West Valley alkaline supernatant

    Energy Technology Data Exchange (ETDEWEB)

    Bray, L.A.; Holton, L.K.; Myers, T.R.; Richardson, G.M.; Wise, B.M.

    1984-01-01

    At the request of West Valley Nuclear Services Co., Inc., the Pacific Northwest Laboratory (PNL) has studied alternative treatment processes for the alkaline PUREX waste presently being stored in Tank 8D2 at West Valley, New York. Five tasks were completed during FY 1983: (1) simulation and characterization of the alkaline supernatant and sludge from the tank. The radiochemical and chemical distributions between the aqueous and solid phase were determined, and the efficiency of washing sludge with water to remove ions such as Na/sup +/ and SO/sub 4//sup 2 -/ was investigated; (2) evaluation of a sodium tetraphenylboron (Na-TPB) precipitation process to recover cesium (Cs) and a sodium titanate (Na-TiA) sorption process to recover strontium (Sr) and plutonium (Pu) from the West Valley Alkaline supernatant. These processes were previously developed and tested at the US Department of Energy's Savannah River Plant; (3) evaluation of an organic cation-exchange resin (Duolite CS-100) to recover Cs and Pu from the alkaline supernatant followed by an organic macroreticular cation exchange resin (Amberlite IRC-718) to recover Sr; (4) evaluation of an inorganic ion exchanger (Linde Ionsiv IE-95) to recover Cs, Sr, and Pu from the alkaline supernatant; and (5) evaluation of Dowex-1,X8 organic anion exchange resin to recover technetium (Tc) from alkaline supernatant. The findings of these tasks are reported. 21 references, 36 figures, 34 tables.

  2. An annotated bibliography of scientific literature on research and management activities conducted in Manitou Experimental Forest

    Science.gov (United States)

    Ilana Abrahamson

    2012-01-01

    The Manitou Experimental Forest (MEF) is part of the USDA Forest Service Rocky Mountain Research Station. Established in 1936, its early research focused on range and watershed management. Currently, the site is home to several meteorological, ecological and biological research initiatives. Our collaborators include the University of Colorado, Colorado State University...

  3. Elevation dependent sensitivity of northern hardwoods to Ca addition at Hubbard Brook Experimental Forest, NH USA

    Science.gov (United States)

    Rakesh Minocha; Stephanie Long; Palaniswamy Thangavel; Subhash C. Minocha; Christopher Eagar; Charles T. Driscoll

    2010-01-01

    Acidic deposition has caused a depletion of calcium (Ca) in the northeastern forest soils. Wollastonite (Ca silicate) was added to watershed 1 (WS1) at the Hubbard Brook Experimental Forest (HBEF) in 1999 to evaluate its effects on various functions of the HBEF ecosystem. The effects of Ca addition on foliar soluble (extractable in 5% HClO4) ions...

  4. Built for the future: New directions in silviculture research and demonstration at Montana's Lubrecht Experimental Forest

    Science.gov (United States)

    Christopher R. Keyes; Thomas E. Perry

    2010-01-01

    Manipulative experiments at the University of Montana’s Lubrecht Experimental Forest have long been set aside as permanent research and demonstration areas (RDA’s) to communicate the tradeoffs among different stand management strategies. However, most of these have either degraded over time or have diminished relevance to contemporary forest management issues. An...

  5. Technology transfer: taking science from the books to the ground at Bent Creek Experimental Forest

    Science.gov (United States)

    Julia Kirschman

    2014-01-01

    Technology transfer has been an important part of the research program at Bent Creek Experimental Forest (Bent Creek) since its establishment in 1925. Our stated mission is to develop and disseminate knowledge and strategies for restoring, managing, sustaining, and enhancing the vegetation and wildlife of upland hardwood-dominated forest ecosystems of the Southern...

  6. Louisiana’s Palustris Experimental Forest: 75 years of research that transformed the South

    Science.gov (United States)

    James P. Barnett; James D. Haywood; Henry A. Pearson

    2011-01-01

    The Palustris Experimental Forest, located on Kisatchie National Forest, has been in existence for 75 years. Research at Palustris has focused on southern pine reforestation technology, including seed production, bareroot nursery production, direct seeding, and planting container seedlings. After establishing pine plantations, researchers developed stand management...

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

    International Nuclear Information System (INIS)

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

    2018-01-01

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

  8. LBA-ECO LC-02 Forest Flammability Data, Catuaba Experimental Farm, Acre, Brazil: 1998

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set provides the results of controlled burns conducted to assess the flammability of mature forests on the Catuaba Experimental Farm of the Federal...

  9. LBA-ECO LC-02 Forest Flammability Data, Catuaba Experimental Farm, Acre, Brazil: 1998

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set provides the results of controlled burns conducted to assess the flammability of mature forests on the Catuaba Experimental Farm of the...

  10. Trees, Shrubs, and Woody Vines of the Bluff Experimental Forest, Warren County, Mississippi

    Science.gov (United States)

    Robert L. Johnson; Elbert L. Little

    1967-01-01

    Nearly 100 species of trees, shrubs, and woody vines grow naturally on the 450-acre Bluff Experimental Forest in west-central Mississippi. This publication lists the plants and provides information on silvical characteristics of the tree species.

  11. Trees and shrubs of the Bartlett Experimental Forest, Carroll County, New Hampshire

    Science.gov (United States)

    Stanley M. Filip; Elbert L., Jr. Little; Elbert L. Little

    1971-01-01

    Sixty-five species of trees and shrubs have been identified as native on the Bartlett Experimental Forest. These species are listed in this paper to provide a record of the woody vegetation of the area.

  12. CEPF Western Ghats Special Series: Metazoan community composition in tree hole aquatic habitats of Silent Valley National Park and New Amarambalam Reserve Forest of the Western Ghats, India

    Directory of Open Access Journals (Sweden)

    K.A. Nishadh

    2012-11-01

    Full Text Available In a study of the metazoan community composition in tree hole aquatic habitat of a tropical rainforest, Silent Valley National Park, and the adjacent moist deciduous forest, New Amarambalam Reserve Forest, of the Western Ghats, 28 different species were recorded from 150 tree hole aquatic habitats with an average of 3-5 species per tree hole. Most of the recorded organisms (96.8% belong to Odonata (dragonflies and damselflies, Heteroptera (bugs, Diptera (flies, Coleoptera (beetles and Trichoptera (caddisflies. The study reports the first record of toe-winged beetle larvae (Ptilodactylidae in a tree hole aquatic habitat. The most significant observation is the prolific occurrence of trichopteran larvae as the second most abundant taxa in tree holes of Silent Valley National Park, and this stands as the first comprehensive record of the entire order in the habitat studied. The study upholds the importance of less explored microhabitats in the Western Ghats region in terms of sustaining unique community composition in the most delicate and extreme habitat conditions. It also puts forward important ecological research questions on biodiversity ecosystem functionality which could impart important lessons for managing and conserving the diminishing tropical evergreen forests which are significant for these unique habitats.

  13. Experimental Analysis of Sublimation Dynamics for Buried Glacier Ice in Beacon Valley, Antarctica

    Science.gov (United States)

    Ehrenfeucht, S.; Dennis, D. P.; Marchant, D. R.

    2017-12-01

    The age of the oldest known buried ice in Beacon Valley, McMurdo Dry Valleys (MDV) Antarctica is a topic of active debate due to its implications for the stability of the East Antarctic Ice Sheet. Published age estimates range from as young as 300 ka to as old as 8.1 Ma. In the upland MDV, ablation occurs predominantly via sublimation. The relict ice in question (ancient ice from Taylor Glacier) lies buried beneath a thin ( 30-70 cm) layer of sublimation till, which forms as a lag deposit as underlying debris-rich ice sublimes. As the ice sublimates, the debris held within the ice accumulates slowly on the surface, creating a porous boundary between the buried-ice surface and the atmosphere, which in turn influences gas exchange between the ice and the atmosphere. Additionally, englacial debris adds several salt species that are ultimately concentrated on the ice surface. It is well documented the rate of ice sublimation varies as a function of overlying till thickness. However, the rate-limiting dynamics under varying environmental conditions, including the threshold thicknesses at which sublimation is strongly retarded, are not yet defined. To better understand the relationships between sublimation rate, till thickness, and long-term surface evolution, we build on previous studies by Lamp and Marchant (2017) and evaluate the role of till thickness as a control on ice loss in an environmental chamber capable of replicating the extreme cold desert conditions observed in the MDV. Previous work has shown that this relationship exhibits exponential decay behavior, with sublimation rate significantly dampened under less than 10 cm of till. In our experiments we pay particular attention to the effect of the first several cm of till in order to quantify the dynamics that govern the transition from bare ice to debris-covered ice. We also examine this transition for various forms of glacier ice, including ice with various salt species.

  14. Tree Planting at the Bent Creek Experimental Forest

    Science.gov (United States)

    John C. Barber

    1953-01-01

    Foresters everywhere are becoming increasingly conscious of the potentialities of tree selection and breeding. In the quest for suitable breeding material, many of the plantations of the past are assuming importance, for each plantation of introduced species may provide information on its adaptability to a certain area and the desirable and undesirable traits which...

  15. Culex pipiens, an experimental efficient vector of West Nile and Rift Valley fever viruses in the Maghreb region.

    Directory of Open Access Journals (Sweden)

    Fadila Amraoui

    Full Text Available West Nile fever (WNF and Rift Valley fever (RVF are emerging diseases causing epidemics outside their natural range of distribution. West Nile virus (WNV circulates widely and harmlessly in the old world among birds as amplifying hosts, and horses and humans as accidental dead-end hosts. Rift Valley fever virus (RVFV re-emerges periodically in Africa causing massive outbreaks. In the Maghreb, eco-climatic and entomologic conditions are favourable for WNV and RVFV emergence. Both viruses are transmitted by mosquitoes belonging to the Culex pipiens complex. We evaluated the ability of different populations of Cx. pipiens from North Africa to transmit WNV and the avirulent RVFV Clone 13 strain. Mosquitoes collected in Algeria, Morocco, and Tunisia during the summer 2010 were experimentally infected with WNV and RVFV Clone 13 strain at titers of 10(7.8 and 10(8.5 plaque forming units/mL, respectively. Disseminated infection and transmission rates were estimated 14-21 days following the exposure to the infectious blood-meal. We show that 14 days after exposure to WNV, all mosquito st developed a high disseminated infection and were able to excrete infectious saliva. However, only 69.2% of mosquito strains developed a disseminated infection with RVFV Clone 13 strain, and among them, 77.8% were able to deliver virus through saliva. Thus, Cx. pipiens from the Maghreb are efficient experimental vectors to transmit WNV and to a lesser extent, RVFV Clone 13 strain. The epidemiologic importance of our findings should be considered in the light of other parameters related to mosquito ecology and biology.

  16. Cost, performance, and esthetic impacts of an experimental forest road in Montana

    Science.gov (United States)

    Rulon B. Gardner

    1978-01-01

    An experimental logging road designed to minimize environmental and esthetic impact was constructed in northwest Montana. The road was single-lane (14-foot finished surface, 3-foot ditch), constructed along the contour. Esthetically, the single-lane experimental road was judged far superior to existing roads on the forest.

  17. Experimental evidence for a phylogenetic Janzen-Connell effect in a subtropical forest

    NARCIS (Netherlands)

    Liu, Xubing; Liang, Minxia; Etienne, Rampal S.; Wang, Yongfan; Staehelin, Christian; Yu, Shixiao

    Observational evidence increasingly suggests that the JanzenConnell effect extends beyond the species boundary. However, this has not been confirmed experimentally. Herein, we present both observational and experimental evidence for a phylogenetic JanzenConnell effect. In a subtropical forest in

  18. Late glacial and Holocene history of the dry forest area in south Colombian Cauca Valley from sites Quilichao and la Teta

    International Nuclear Information System (INIS)

    Berrio, Juan Carlos; Hooghiemstra, Henry; Marchant, Rob; Rangel Orlando

    2002-01-01

    Two sedimentary cores with records of pollen and charcoal content within a chronology provided by radiocarbon are presented from the southern Cauca Valley in Colombia (1020 m). These records document the late glacial and Holocene dry forest vegetation, fire and environment history. Specifically, core Quilichao -1 (640 cm; 3 degrade 6' N, 76 degrade 31' W) represents the periods of 13/150-7720 14 C yr BP and following a hiatus from 2880 14 C yr BP to recent. Core la Teta - 2 (250 cm; 3 degrade 5' N, 76 degrade 32' W) provides a record from 8700 14 C yr BP around 13/150 21 4 C yr BP Quilichao shown an active late glacial drainage system and presence of dry forest. From 11/465-10/520 14 C yr BP dry forest consists mainly of Crotalaria Moraceae Urticaceae, Melastomataceae, Piper and low stature trees, such as Acalypha, Alchornea, Cecropia and Celtis. At higher elevation on the slopes Andean forest with Quercus, Hedyosmum, Myrica and Alnus are common

  19. Compensating effect of sap velocity for stand density leads to uniform hillslope-scale forest transpiration across a steep valley cross-section

    Science.gov (United States)

    Renner, Maik; Hassler, Sibylle; Blume, Theresa; Weiler, Markus; Hildebrandt, Anke; Guderle, Marcus; Schymanski, Stan; Kleidon, Axel

    2016-04-01

    Roberts (1983) found that forest transpiration is relatively uniform across different climatic conditions and suggested that forest transpiration is a conservative process compensating for environmental heterogeneity. Here we test this hypothesis at a steep valley cross-section composed of European Beech in the Attert basin in Luxemburg. We use sapflow, soil moisture, biometric and meteorological data from 6 sites along a transect to estimate site scale transpiration rates. Despite opposing hillslope orientation, different slope angles and forest stand structures, we estimated relatively similar transpiration responses to atmospheric demand and seasonal transpiration totals. This similarity is related to a negative correlation between sap velocity and site-average sapwood area. At the south facing sites with an old, even-aged stand structure and closed canopy layer, we observe significantly lower sap velocities but similar stand-average transpiration rates compared to the north-facing sites with open canopy structure, tall dominant trees and dense understorey. This suggests that plant hydraulic co-ordination allows for flexible responses to environmental conditions leading to similar transpiration rates close to the water and energy limits despite the apparent heterogeneity in exposition, stand density and soil moisture. References Roberts, J. (1983). Forest transpiration: A conservative hydrological process? Journal of Hydrology 66, 133-141.

  20. Soil water storage and groundwater behaviour in a catenary sequence beneath forest in central Amazonia: I. Comparisons between plateau, slope and valley floor

    Directory of Open Access Journals (Sweden)

    M. G. Hodnett

    1997-01-01

    Full Text Available Soil water storage was monitored in three landscape elements in the forest (plateau, slope and valley floor over a 3 year period to identify differences in sub-surface hydrological response. Under the plateau and slope, the changes of storage were very similar and there was no indication of surface runoff on the slope. The mean maximum seasonal storage change was 156 mm in the 2 m profile but it was clear that, in the dry season, the forest was able to take up water from below 3.6 m. Soil water availability was low. Soil water storage changes in the valley were dominated by the behaviour of a shallow water table which, in normal years, varied between 0.1 m below the surface at the end of the wet season and 0.8 m at the end of the dry season. Soil water storage changes were small because root uptake was largely replenished by groundwater flow towards the stream. The groundwater behaviour is controlled mainly by the deep drainage from beneath the plateau and slope areas. The groundwater gradient beneath the slope indicated that recharge beneath the plateau and slope commences only after the soil water deficits from the previous dry season have been replenished. Following a wet season with little recharge, the water table fell, ceasing to influence the valley soil water storage, and the stream dried up. The plateau and slope, a zone of very high porosity between 0.4 and 1.1 m, underlain by a less conductive layer, is a probable route for interflow during, and for a few hours after, heavy and prolonged rainfall.

  1. Managing the forest for more than the trees: effects of experimental timber harvest on forest Lepidoptera.

    Science.gov (United States)

    Summerville, Keith S

    2011-04-01

    Studies of the effects of timber harvest on forest insect communities have rarely considered how disturbance from a range of harvest levels interacts with temporal variation in species diversity to affect community resistance to change. Here I report the results of a landscape-scale, before-and-after, treatment-control experiment designed to test how communities of forest Lepidoptera experience (1) changes in species richness and composition and (2) shifts in species dominance one year after logging. I sampled Lepidoptera from 20 forest stands allocated to three harvest treatments (control, even-aged shelterwood or clearcuts, and uneven-aged group selection cuts) within three watersheds at Morgan-Monroe State Forest, Indiana, USA. Moths were sampled from all forest stands one year prior to harvest in 2007 and immediately post-harvest in 2009. Species composition was most significantly affected by temporal variation between years, although uneven-aged management also caused significant changes in lepidopteran community structure. Furthermore, species richness of Lepidoptera was higher in 2007 compared to 2009 across all watersheds and forest stands. The decrease in species richness between years, however, was much larger in even-aged and uneven-aged management units compared to the control. Furthermore, matrix stands within the even-aged management unit demonstrated the highest resistance to species loss within any management unit. Species dominance was highly resistant to effects of timber harvest, with pre- and post-harvest values for Simpson diversity nearly invariant. Counter to prediction, however, the suite of dominant taxa differed dramatically among the three management units post-harvest. My results suggest that temporal variation may have strong interactions with timber harvest, precipitating loss of nearly 50% species richness from managed stands regardless of harvest level. Even-aged management, however, appeared to leave the smallest "footprint" on moth

  2. Whole-ecosystem experimental manipulations of tropical forests

    Czech Academy of Sciences Publication Activity Database

    Fayle, Tom Maurice; Turner, E. C.; Basset, Yves; Ewers, R. M.; Reynolds, G.; Novotný, Vojtěch

    2015-01-01

    Roč. 30, č. 6 (2015), s. 334-346 ISSN 0169-5347 R&D Projects: GA ČR GA14-32302S; GA ČR(CZ) GA14-04258S; GA ČR GB14-36098G Grant - others:Euroepan Social Fund(CZ) CZ.1.07/2.3.00/20.0064 Institutional support: RVO:60077344 Keywords : tropical forests Subject RIV: EH - Ecology, Behaviour Impact factor: 16.735, year: 2015 http://www.cell.com/trends/ecology-evolution/pdf/S0169-5347(15)00069-5.pdf

  3. Forests

    Science.gov (United States)

    Louis R. Iverson; Mark W. Schwartz

    1994-01-01

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

  4. Changes of seasonally dry forest in the Colombian Patía Valley during the early and middle Holocene and the development of a dry climatic record for the northernmost Andes

    NARCIS (Netherlands)

    González-Carranza, Z.; Berrío, J.C.; Hooghiemstra, H.; Duivenvoorden, J.F.; Behling, H.

    2008-01-01

    A 450 cm long sediment core was collected from a swamp in the dry forest ecosystem of the Patía Valley in Colombia (02°02′ N, 77° W at 750 m elevation). This core (Potrerillo-2) was analysed using pollen, lithostratigraphy and radiocarbon dates and was correlated with an already existing dataset

  5. Phylogenetic impoverishment of Amazonian tree communities in an experimentally fragmented forest landscape.

    Science.gov (United States)

    Santos, Bráulio A; Tabarelli, Marcelo; Melo, Felipe P L; Camargo, José L C; Andrade, Ana; Laurance, Susan G; Laurance, William F

    2014-01-01

    Amazonian rainforests sustain some of the richest tree communities on Earth, but their ecological and evolutionary responses to human threats remain poorly known. We used one of the largest experimental datasets currently available on tree dynamics in fragmented tropical forests and a recent phylogeny of angiosperms to test whether tree communities have lost phylogenetic diversity since their isolation about two decades previously. Our findings revealed an overall trend toward phylogenetic impoverishment across the experimentally fragmented landscape, irrespective of whether tree communities were in 1-ha, 10-ha, or 100-ha forest fragments, near forest edges, or in continuous forest. The magnitude of the phylogenetic diversity loss was low (phylogenetic diversity, we observed a significant decrease of 50% in phylogenetic dispersion since forest isolation, irrespective of plot location. Analyses based on tree genera that have significantly increased (28 genera) or declined (31 genera) in abundance and basal area in the landscape revealed that increasing genera are more phylogenetically related than decreasing ones. Also, the loss of phylogenetic diversity was greater in tree communities where increasing genera proliferated and decreasing genera reduced their importance values, suggesting that this taxonomic replacement is partially underlying the phylogenetic impoverishment at the landscape scale. This finding has clear implications for the current debate about the role human-modified landscapes play in sustaining biodiversity persistence and key ecosystem services, such as carbon storage. Although the generalization of our findings to other fragmented tropical forests is uncertain, it could negatively affect ecosystem productivity and stability and have broader impacts on coevolved organisms.

  6. Nursery stock quality as an indicator of bottomland hardwood forest restoration success in the Lower Mississippi River Alluvial Valley

    Science.gov (United States)

    Douglass F. Jacobs; Rosa C. Goodman; Emile S. Gardiner; K Frances Salifu; Ronald P. Overton; George Hernandez

    2012-01-01

    Seedling morphological quality standards are lacking for bottomland hardwood restoration plantings in the Lower Mississippi River Alluvial Valley, USA, which may contribute toward variable restoration success. We measured initial seedling morphology (shoot height, root collar diameter, number of first order lateral roots, fresh mass, and root volume), second year field...

  7. Structural diversity, its components and regenerating capacity of lesser Himalayan forests vegetation of Nikyal valley District Kotli (A.K), Pakistan.

    Science.gov (United States)

    Amjad, Muhammad Shoaib; Arshad, Muhammad; Chaudhari, Sunbal Khalil

    2014-09-01

    To report the patterns of species diversity, and regenerating capacity in the forest of Nikyal valley in relation to environmental variables and underlying anthropogenic influence. A study area was selected in a traditionally managed mountain woody pasture during July 2012 to June 2013. The area was sampled by quadrat method. The quadrats were laid down at regular intervals of 150 m. The size of quadrats was kept 10×10, 5×5 and 1×1 m(2) for trees, shrubs and herbs respectively. Density, frequency and cover were recorded. Importance value index of each plant species was calculated and plant communities were named after the plant species having the highest IV. Then diversity, its components and regenerating capacity were calculated with their formulas. Shannon's diversity ranged from 2.75 to 3.31, Simpson's diversity, 0.90 to 0.95; Menhinick's diversity, 0.83 to 1.19; evenness, 0.41 to 0.65; species richness, 4.89 to 6.08 and maturity index, 30 to 44 species distribution pattern. Diversity values were similar to the other Himalayan forests. Pinus roxburghaii was the only regenerating species whereas the remaining four tree species including Qurecus dilatata regenerate up to 100 cm; they are at extreme risk of elimination due to anthropogenic factors. Nikyal valley is under severe deforestation pressure for fuel and timber value. There is an urgent need to promote the ethics among the people that improvement and conservation of natural resources are critical for land and soil management. Copyright © 2014 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  8. Effects of watershed experiments on water chemistry at the Marcell Experimental Forest. Chapter 14.

    Science.gov (United States)

    Stephen D. Sebestyen; Elon S. Verry

    2011-01-01

    The Marcell Experimental Forest (MEF) was established during the 1960s to study the hydrology and ecology of lowland watersheds where upland mineral soils drain to central peatlands (Boelter and Verry 1977). The effects of seven large-scale manipulations on water chemistry have been studied on the MEF watersheds and the data now span up to four decades. In this chapter...

  9. Summary of climatic data for the Bonanza Creek Experimental Forest, interior Alaska.

    Science.gov (United States)

    Richard J. Barney; Erwin R. Berglund

    1973-01-01

    A summary of climatic data during the 1968-71 growing seasons is presented for the subarctic Bonanza Creek Experimental Forest located near Fairbanks, Alaska. Data were obtained from three weather station sites at elevations of 1,650, 1,150, and 550 feet from May until September each year. Data are for relative humidity, rainfall, and maximum, minimum, and mean...

  10. Spatial and seasonal dynamics of surface soil carbon in the Luquillo Experimental Forest, Puerto Rico.

    Science.gov (United States)

    Hongqing Wang; Joseph D. Cornell; Charles A.S. Hall; David P. Marley

    2002-01-01

    We developed a spatially-explicit version of the CENTURY soil model to characterize the storage and flux of soil organic carbon (SOC, 0–30 cm depth) in the Luquillo Experimental Forest (LEF), Puerto Rico as a function of climate, vegetation, and soils. The model was driven by monthly estimates of average air temperature, precipitation, and potential evapotranspiration...

  11. Hydrogen ion input to the Hubbard Brook Experimental Forest, New Hampshire, during the last decade

    Science.gov (United States)

    Gene E. Likens; F. Herbert Bormann; John S. Eaton; Robert S. Pierce; Noye M. Johnson

    1976-01-01

    Being downwind of eastern and midwestern industrial centers, the Hubbard Brook Experimental Forest offers a prime location to monitor long-term trends in atmospheric chemistry. Continuous measurements of precipitation chemistry during the last 10 years provide a measure of recent changes in precipitation inputs of hydrogen ion. The weighted average pH of precipitation...

  12. Vascular flora of the Penobscot Experimental Forest, with provisional lists of lichens and bryophytes

    Science.gov (United States)

    Alison C. Dibble

    2014-01-01

    A compilation of plant lists from all available sources since the 1950s represents the flora of the Penobscot Experimental Forest (PEF), Bradley, Maine. More than 300 taxa of vascular plants in 71 families and 186 genera are included. Approximately 85 percent of the taxa are native to Maine. Ten of 45 nonnative species are considered invasive. Infraspecific taxa have...

  13. Chemistry of burning the forest floor during the FROSTFIRE experimental burn, interior Alaska, 1999.

    Science.gov (United States)

    J.W. Harden; J.C. Neff; D.V. Sandberg; M.R. Turetsky; R. Ottmar; G. Gleixner; T.L. Fries; K.L. Manies

    2004-01-01

    Wildfires represent one of the most common disturbances in boreal regions, and have the potential to reduce C, N, and Hg stocks in soils while contributing to atmospheric emissions. Organic soil layers of the forest floor were sampled before and after the FROSTFIRE experimental burn in interior Alaska, and were analyzed for bulk density, major and trace elements, and...

  14. Temperature adaptation of bacterial communities in experimentally warmed forest soils.

    Science.gov (United States)

    Rousk, Johannes; Frey, Serita D; Bååth, Erland

    2012-10-01

    A detailed understanding of the influence of temperature on soil microbial activity is critical to predict future atmospheric CO 2 concentrations and feedbacks to anthropogenic warming. We investigated soils exposed to 3-4 years of continuous 5 °C-warming in a field experiment in a temperate forest. We found that an index for the temperature adaptation of the microbial community, T min for bacterial growth, increased by 0.19 °C per 1 °C rise in temperature, showing a community shift towards one adapted to higher temperature with a higher temperature sensitivity (Q 10(5-15 °C) increased by 0.08 units per 1 °C). Using continuously measured temperature data from the field experiment we modelled in situ bacterial growth. Assuming that warming did not affect resource availability, bacterial growth was modelled to become 60% higher in warmed compared to the control plots, with the effect of temperature adaptation of the community only having a small effect on overall bacterial growth (bacterial growth, most likely due to substrate depletion because of the initially higher growth in warmed plots. When this was factored in, the result was similar rates of modelled in situ bacterial growth in warmed and control plots after 3 years, despite the temperature difference. We conclude that although temperature adaptation for bacterial growth to higher temperatures was detectable, its influence on annual bacterial growth was minor, and overshadowed by the direct temperature effect on growth rates. © 2012 Blackwell Publishing Ltd.

  15. Eastern hemlock response to even- and uneven-age management in the Acadian forest: results from the Penobscot Experimental Forest long-term silviculture study

    Science.gov (United States)

    John C. Brissette; Laura S. Kenefic

    2000-01-01

    Eastern hemlock (Tsuga canadensis (L.) Carr.) is an important tree species in the mixed-species conifer forests of northern New England and adjacent Canada. Hemlock is very tolerant of understory conditions; consequently, it responds differently to various silvicultural treatments. In a long-term study at the Penobscot Experimental Forest in east-...

  16. Structural characterization of the gallery forest of the Guisa Agroforestry Experimental Station

    Directory of Open Access Journals (Sweden)

    José Luis Rodríguez Sosa

    2018-01-01

    Full Text Available The work was carried out in the gallery forest of the Cupaynicú stream, belonging to the Guisa Agroforestry Experimental Station, with the objective of characterizing its structure. Eight parcels of 500 m2 were randomly raised, in them the species were identified, their height and diameter were measured. The flora was analyzed through the origin of the species and the frequency histogram. The structure of the forest was analyzed through the diametric structure and the Value Index of Ecological Importance, the vertical structure was described taking into consideration the forest strata as well as the preparation of the canopy diagram. A descriptive analysis of the parameters diameter, height and basal area was made to study the parametric structure. The richness of the riparian forest was evidenced by the registry of 25 families, 40 genera and 43 species, as well as the predominance of the Meliaceae family followed by Lauraceae, Mimosaceae and Sapindaceae, which reflects the high timber value, melliferous and ecological of the same. The species Roystonea regia, Sterculiaapetala, Dendropanaxarboreus, Andirainermis and Mangifera indica, determine the physiognomy of the gallery Forest. The trees reach 33 cm in diameter and 18.27 m in height on average, although the presence of trees with 30 m is the most frequent, which denotes the irregular structure of the forest.

  17. Limited carbon storage in soil and litter of experimental forest plots under increased atmospheric CO2

    International Nuclear Information System (INIS)

    Schlesinger, W.H.; Lichter, J.

    2001-01-01

    The current rise in atmospheric CO 2 concentration is thought to be mitigated in part by carbon sequestration within forest ecosystems, where carbon can be stored in vegetation or soils. The storage of carbon in soils is determined by the fraction that is sequestered in persistent organic materials, such as humus. In experimental forest plots of loblolly pine (Pinus taeda) exposed to high CO 2 concentrations, nearly half of the carbon uptake is allocated to short-lived tissues, largely foliage. These tissues fall to the ground and decompose, normally contributing only a small portion of their carbon content to refractory soil humic materials. Such findings call into question the role of soils as long-term carbon sinks, and show the need for a better understanding of carbon cycling in forest soils. Here we report a significant accumulation of carbon in the litter layer of experimental forest plots after three years of growth at increased CO 2 concentrations (565 μ l 1 ). But fast turnover times of organic carbon in the litter layer (of about three years) appear to constrain the potential size of this carbon sink. Given the observation that carbon accumulation in the deeper mineral soil layers was absent, we suggest that significant, long-term net carbon sequestration in forest soils is unlikely. (author)

  18. Downscaling of surface moisture flux and precipitation in the Ebro Valley (Spain using analogues and analogues followed by random forests and multiple linear regression

    Directory of Open Access Journals (Sweden)

    G. Ibarra-Berastegi

    2011-06-01

    Full Text Available In this paper, reanalysis fields from the ECMWF have been statistically downscaled to predict from large-scale atmospheric fields, surface moisture flux and daily precipitation at two observatories (Zaragoza and Tortosa, Ebro Valley, Spain during the 1961–2001 period. Three types of downscaling models have been built: (i analogues, (ii analogues followed by random forests and (iii analogues followed by multiple linear regression. The inputs consist of data (predictor fields taken from the ERA-40 reanalysis. The predicted fields are precipitation and surface moisture flux as measured at the two observatories. With the aim to reduce the dimensionality of the problem, the ERA-40 fields have been decomposed using empirical orthogonal functions. Available daily data has been divided into two parts: a training period used to find a group of about 300 analogues to build the downscaling model (1961–1996 and a test period (1997–2001, where models' performance has been assessed using independent data. In the case of surface moisture flux, the models based on analogues followed by random forests do not clearly outperform those built on analogues plus multiple linear regression, while simple averages calculated from the nearest analogues found in the training period, yielded only slightly worse results. In the case of precipitation, the three types of model performed equally. These results suggest that most of the models' downscaling capabilities can be attributed to the analogues-calculation stage.

  19. Co-evolution of soils and vegetation in the Aísa Valley Experimental Station (Central Pyrenees)

    Science.gov (United States)

    Serrano Muela, Maria Pilar; Nadal Romero, Estela; Lasanta, Teodoro; María García Ruiz, José

    2013-04-01

    Soils and vegetation tend to evolve jointly in relation to climate evolution and the impacts of human activity. This study analyzes soil and vegetation characteristics under various plant covers, using information from the Aísa Valley Experimental Station (AVES), Spanish Pyrenees, from 1991 to 2010. The land uses considered were: dense shrub cover, grazing meadow, abandoned field, cereal (barley), abandoned shifting agriculture, active shifting agriculture, burnt1 and burnt2 plots, and in-fallow plot. All the plots were installed on a field abandoned 45 years ago. Some of the plots did not change in plant cover through the study period (e.g., the meadow, cereal and shifting agriculture plots), but others underwent changes in density and composition, such as: (i) The dense shrub cover plot represents the natural evolution of the abandoned field. When the AVES was equipped, this plot was completely dominated by Genista scorpius, with a few stands of Rosa gr. Canina. Twenty years later, Genista scorpius is affected of senescence and shows almost no regeneration capacity. (ii) The abandoned field had previously been cultivated with cereals until 1993. Once abandoned, the progression of plant colonization was very rapid. Firstly with grasses and, 10 years later, with Genista scorpius. At present, this latter occupies more than 50% of the plot. (iii) The evolution of plant colonization in the abandoned shifting agriculture plot was slower than that in the 'normal' abandoned field, mainly because of the differences in fertilization when they were cultivated. (iv) One of the burnt plots evolved from 0% to a coverage of almost 100% in a shot period, whereas the other plot remained with a shrub density of about 60% several years after the fire. Soil samples (superficial and depth) were analyzed to obtain physical and chemical properties: structure, texture, pH, CaCO3, Organic Matter and various anions and cations. The main purpose was to detect differences in the soil

  20. Drivers of variability in water use of two co-occurring species in a subalpine forest in Jiuzhaigou Valley, Southwest of China

    Science.gov (United States)

    Yan, C.; Zhao, W.; Wang, Y.; Zhang, Q.; Qiu, G. Y.

    2016-12-01

    Co-occur species with different sensitivity to soil water may be particularly useful in evaluating water use by different forest stands as well as the response of species distribution, forest structure and stand composition to soil water availability in water-limited area. To clarify the species-specific water use strategy and provide insights into the possible succession trend, variations in sap flow and environmental conditions were investigated for two co-occur species (Betula albo-sinensis and Pinus tabulaeformis) in a mixed forest in Jiuzhaigou Valley in 2014. Sap flow was measured by Granier-type thermal dissipation probes and soil water content was measured by time-domain reflectometry probes for a successive period. Pinus tabulaeformis and Betua albo-sinensis species showed different responses to meteorological factors under different soil water conditions. Despite that whole tree water use was much higher for Pinus tabulaeformis due to greater sapwood area, sap flux density of the other co-occurring species Betua albo-sinensis was higher throughout the growing season. Normalized sap flux density (Fd) could be mostly well fitted to solar radiation (Rs), vapor pressure deficit (VPD), or the variable of transpiration (VT) by the exponential saturation function. Much better fitted curves were found for Fd -VPD and Fd - VT datasets than Fd - Rs datasets. For most datasets, normalized Fd increased rapidly when the environmental factors were below their threshold values, but reached an asymptote thereafter. Based on the species' differences in fitting parameters and the average maximum sap flow level under different soil water conditions, it was concluded that Pinus tabulaeformis was sensitive to soil water conditions and tolerant of low soil water availability, while Betua albo-sinensis was insensitive to soil moisture and needed to access to similarly high amount of soil water in the growing season after leaf expansion. These results indicated possible

  1. A Regional Guidebook for Applying the Hydrogeomorphic Approach to Assessing Functions of Forested Wetlands in the Mississippi Alluvial Valley

    Science.gov (United States)

    2013-07-01

    regions of applicability if they prefer, and they will yield essentially the same results as this guidebook. However, this version is designed to...in the 16th century, natural levees of the major rivers were extensively used for maize agriculture by Native Americans (Hudson 1997). By the time...Together these indicate whether the stand has a structure typical of a mature forest with “ gap ” regeneration processes in place. The second term of

  2. Seed dispersal turns an experimental plantation on degraded land into a novel forest in urban northern Puerto Rico

    Science.gov (United States)

    Oscar Abelleira; Elvia J. Meléndez Ackerman; Diana García Montiel; John A. Parrotta

    2015-01-01

    Planting tree species with desirable traits may catalyze forest regeneration in increasingly common degraded lands by restoring soil properties and attracting seed dispersers. We sampled forest regeneration in an experimental plantation of Albizia lebbek, an introduced N-fixing species, on a degraded pasture in northern Puerto Rico, 27 years after its establishment. We...

  3. Invertebrates of The H.J. Andrews Experimental Forest, Western Cascades, Oregon: III. The Orthoptera (Grasshoppers and Crickets).

    Science.gov (United States)

    David C. Lightfoot

    1986-01-01

    An inventory of Orthoptera (grasshoppers and crickets) at the H.J. Andrews Experimental Forest, near Blue River, Oregon, was conducted to determine the species present and ecological relationships. A key for identification and an annotated list are presented. From qualitative assessments of successional habitat relationships, generalized species associations of forest...

  4. Nonnative invasive plants in the Penobscot Experimental Forest in Maine, USA: influence of site, silviculture, and land use history

    Science.gov (United States)

    Elizabeth Olson; Laura S. Kenefic; Alison C. Dibble; John C. Brissette

    2011-01-01

    We investigated the occurrence of nonnative invasive plants on approximately 175 ha comprising a long-term, 60-year-old U.S. Forest Service silvicultural experiment and old-field stands in the Penobscot Experimental Forest (PEF) in central Maine. Stands in the silvicultural experiment were never cleared for agriculture, but have been repeatedly partially cut. Our...

  5. Comparing vegetation cover in the Santee Experimental Forest, South Carolina (USA), before and after hurricane Hugo: 1989-2011

    Science.gov (United States)

    Giovanni R. Cosentino

    2013-01-01

    Hurricane Hugo struck the coast of South Carolina on September 21, 1989 as a category 4 hurricane on the Saffir-Simpson Scale. Landsat Thematic mapper was utilized to determine the extent of damage experienced at the Santee Experimental Forest (SEF) (a part of Francis Marion National Forest) in South Carolina. Normalized Difference Vegetation Index (NDVI) and the...

  6. Research publications of the Cascade Head Experimental Forest and Scenic Research Area, Oregon Coast Range, 1934 to 1990.

    Science.gov (United States)

    Sarah E. Greene; Tawny Blinn

    1991-01-01

    A list of publications resulting from research at the Cascade Head Experimental Forest and Scenic Research Area, Siuslaw National Forest, Oregon, from 1934 to 1990 is presented. Over 200 publications are listed, including papers, theses, and reports. An index is provided that cross-references the listings under appropriate keywords.

  7. Changing forest water yields in response to climate warming: results from long-term experimental watershed sites across North America

    Science.gov (United States)

    Irena F. Creed; Adam T. Spargo; Julia A. Jones; Jim M. Buttle; Mary B. Adams; Fred D. Beall; Eric G. Booth; John L. Campbell; Dave Clow; Kelly Elder; Mark B. Green; Nancy B. Grimm; Chelcy Miniat; Patricia Ramlal; Amartya Saha; Stephen Sebestyen; Dave Spittlehouse; Shannon Sterling; Mark W. Williams; Rita Winkler; Huaxia. Yao

    2014-01-01

    Climate warming is projected to affect forest water yields but the effects are expected to vary.We investigated how forest type and age affect water yield resilience to climate warming. To answer this question, we examined the variability in historical water yields at long-term experimental catchments across Canada and the United States over 5-year cool and warm...

  8. Influence of large wood on channel morphology and sediment storage in headwater mountain streams, Fraser Experimental Forest, Colorado

    Science.gov (United States)

    Sandra E. Ryan; Erica L. Bishop; J. Michael Daniels

    2014-01-01

    Large fallen wood can have a significant impact on channel form and process in forested mountain streams. In this study, four small channels on the Fraser Experimental Forest near Fraser, Colorado, USA, were surveyed for channel geometries and large wood loading, including the size, source, and characteristics of individual pieces. The study is part of a larger effort...

  9. Effects of experimental nitrogen additions on plant diversity in tropical forests of contrasting disturbance regimes in southern China

    International Nuclear Information System (INIS)

    Lu Xiankai; Mo Jiangming; Gilliam, Frank S.; Yu Guirui; Zhang Wei; Fang Yunting; Huang Juan

    2011-01-01

    Responses of understory plant diversity to nitrogen (N) additions were investigated in reforested forests of contrasting disturbance regimes in southern China from 2003 to 2008: disturbed forest (with harvesting of understory vegetation and litter) and rehabilitated forest (without harvesting). Experimental additions of N were administered as the following treatments: Control, 50 kg N ha -1 yr -1 , and 100 kg N ha -1 yr -1 . Nitrogen additions did not significantly affect understory plant richness, density, and cover in the disturbed forest. Similarly, no significant response was found for canopy closure in this forest. In the rehabilitated forest, species richness and density showed no significant response to N additions; however, understory cover decreased significantly in the N-treated plots, largely a function of a significant increase in canopy closure. Our results suggest that responses of plant diversity to N deposition may vary with different land-use history, and rehabilitated forests may be more sensitive to N deposition. - Highlights: → Nitrogen addition had no significant effect on understory plant diversity in the disturbed forest. → Nitrogen addition significantly decreased understory plant cover. → Nitrogen addition had no effect on richness and density in the rehabilitated forest. → The decrease is largely a function of a significant increase in canopy closure. → Land-use practices may dominate the responses of plant diversity to N addition. - Research in disturbed forests of southeastern China demonstrates that land-use history can substantially alter effects of excess nitrogen deposition on plant diversity of tropical forest ecosystems.

  10. An annotated list of the flora of the Bisley Area Luquillo Experimental Forest, Puerto Rico 1987 to 1992

    Science.gov (United States)

    Jesus Danilo Chinea; Renee J. Beymer; Carlos Rivera; Ines Sastre de Jeses; F.N. Scatena

    1993-01-01

    Known species of plants, including bryophytes and ferns, are listed for the area of the Bisley experimental watershed area, a subtropical wet forest in the Luquillo Mountains of northeastern Puerto Rico.

  11. [Effects of grazing disturbance on soil active organic carbon in mountain forest-arid valley ecotone in the upper reaches of Minjiang River].

    Science.gov (United States)

    Liu, Shan-Shan; Zhang, Xing-Hua; Gong, Yuan-Bo; Li, Yuan; Wang, Yan; Yin, Yan-Jie; Ma, Jin-Song; Guo, Ting

    2014-02-01

    Effects of grazing disturbance on the soil carbon contents and active components in the four vegetations, i.e., artificial Robinia pseudoacacia plantation, artificial poplar plantation, Berberis aggregate shrubland and grassland, were studied in the mountain forest-arid valley ecotone in the upper Minjiang River. Soil organic carbon and active component contents in 0-10 cm soil layer were greater than in 10-20 cm soil layer at each level of grazing disturbance. With increasing the grazing intensity, the total organic carbon (TOC), light fraction organic carbon (LFOC), particulate organic carbon (POC) and easily oxidized carbon (LOC) contents in 0-10 cm soil layer decreased gradually in the artificial R. pseudoacacia plantation. The LFOC content decreased, the POC content increased, and the TOC and LOC contents decreased initially and then increased with increasing the grazing intensity in the artificial poplar plantation. The POC content decreased, and the TOC, LFOC and LOC contents decreased initially and then increased with increasing the grazing intensity in the B. aggregate shrubland. The POC and TOC contents decreased, and the LFOC and LOC contents decreased initially and then increased with increasing the grazing intensity in the grassland. The decreasing ranges of LOC, LFOC and POC contents were 0.1-7.9 times more than that of TOC content. There were significant positive relationships between TOC and LOC, LFOC and POC, suggesting that the active organic carbon components could reflect the change of soil total carbon content.

  12. Identify temporal trend of air temperature and its impact on forest stream flow in Lower Mississippi River Alluvial Valley using wavelet analysis.

    Science.gov (United States)

    Ouyang, Ying; Parajuli, Prem B; Li, Yide; Leininger, Theodor D; Feng, Gary

    2017-08-01

    Characterization of stream flow is essential to water resource management, water supply planning, environmental protection, and ecological restoration; while air temperature variation due to climate change can exacerbate stream flow and add instability to the flow. In this study, the wavelet analysis technique was employed to identify temporal trend of air temperature and its impact upon forest stream flows in Lower Mississippi River Alluvial Valley (LMRAV). Four surface water monitoring stations, which locate near the headwater areas with very few land use disturbances and the long-term data records (60-90 years) in the LMRAV, were selected to obtain stream discharge and air temperature data. The wavelet analysis showed that air temperature had an increasing temporal trend around its mean value during the past several decades in the LMRAV, whereas stream flow had a decreasing temporal trend around its average value at the same time period in the same region. Results of this study demonstrated that the climate in the LMRAV did get warmer as time elapsed and the streams were drier as a result of warmer air temperature. This study further revealed that the best way to estimate the temporal trends of air temperature and stream flow was to perform the wavelet transformation around their mean values. Published by Elsevier Ltd.

  13. Plants as highly diverse sources of construction wood, handicrafts and fibre in the Heihe valley (Qinling Mountains, Shaanxi, China): the importance of minor forest products.

    Science.gov (United States)

    Kang, Jin; Kang, Yongxiang; Feng, Jing; Liu, Mengying; Ji, Xiaolian; Li, Dengwu; Stawarczyk, Kinga; Łuczaj, Łukasz

    2017-06-30

    Chinese rural communities living among species-rich forests have little documentation on species used to make handicrafts and construction materials originating from the surrounding vegetation. Our research aimed at recording minor wood uses in the Heihe valley in the Qinling mountains. We carried out 37 semi-structured interviews in seven villages. We documented the use of 84 species of plants. All local large canopy trees are used for some purpose. Smaller trees and shrubs which are particularly hard are selectively cut. The bark of a few species was used to make shoes, hats, steamers and ropes, but this tradition is nearly gone. A few species, mainly bamboo, are used for basket making, and year-old willow branches are used for brushing off the chaff during wheat winnowing. The traditional use of wood materials documented suggests that some rare and endangered tree species may have been selectively cut due to their valuable wood, e.g. Fraxinus mandshurica and Taxus wallichiana var. chinensis. Some other rare species, e.g. Dipteronia sinensis, are little used and little valued.

  14. Classification and ordination of understory vegetation using multivariate techniques in the Pinus wallichiana forests of Swat Valley, northern Pakistan

    Science.gov (United States)

    Rahman, Inayat Ur; Khan, Nasrullah; Ali, Kishwar

    2017-04-01

    An understory vegetation survey of the Pinus wallichiana-dominated temperate forests of Swat District was carried out to inspect the structure, composition and ecological associations of the forest vegetation. A quadrat method of sampling was used to record the floristic and phytosociological data necessary for the analysis using 300 quadrats of 10 × 10 m each. Some vegetation parameters viz. frequency and density for trees (overstory vegetation) as well as for the understory vegetation were recorded. The results revealed that in total, 92 species belonging to 77 different genera and 45 families existed in the area. The largest families were Asteraceae, Rosaceae and Lamiaceae with 12, ten and nine species, respectively. Ward's agglomerative cluster analysis for tree species resulted in three floristically and ecologically distinct community types along different topographic and soil variables. Importance value indices (IVI) were also calculated for understory vegetation and were subjected to ordination techniques, i.e. canonical correspondence analysis (CCA) and detrended correspondence analysis (DCA). DCA bi-plots for stands show that most of the stands were scattered around the centre of the DCA bi-plot, identified by two slightly scattered clusters. DCA for species bi-plot clearly identified three clusters of species revealing three types of understory communities in the study area. Results of the CCA were somewhat different from the DCA showing the impact of environmental variables on the understory species. CCA results reveal that three environmental variables, i.e. altitude, slope and P (mg/kg), have a strong influence on distribution of stands and species. Impact of tree species on the understory vegetation was also tested by CCA which showed that four tree species, i.e. P. wallichiana A.B. Jackson, Juglans regia Linn., Quercus dilatata Lindl. ex Royle and Cedrus deodara (Roxb. ex Lamb.) G. Don, have strong influences on associated understory vegetation. It

  15. Forests

    International Nuclear Information System (INIS)

    Melin, J.

    1997-01-01

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

  16. Climate Impacts on Soil Carbon Processes along an Elevation Gradient in the Tropical Luquillo Experimental Forest

    Directory of Open Access Journals (Sweden)

    Dingfang Chen

    2017-03-01

    Full Text Available Tropical forests play an important role in regulating the global climate and the carbon cycle. With the changing temperature and moisture along the elevation gradient, the Luquillo Experimental Forest in Northeastern Puerto Rico provides a natural approach to understand tropical forest ecosystems under climate change. In this study, we conducted a soil translocation experiment along an elevation gradient with decreasing temperature but increasing moisture to study the impacts of climate change on soil organic carbon (SOC and soil respiration. As the results showed, both soil carbon and the respiration rate were impacted by microclimate changes. The soils translocated from low elevation to high elevation showed an increased respiration rate with decreased SOC content at the end of the experiment, which indicated that the increased soil moisture and altered soil microbes might affect respiration rates. The soils translocated from high elevation to low elevation also showed an increased respiration rate with reduced SOC at the end of the experiment, indicating that increased temperature at low elevation enhanced decomposition rates. Temperature and initial soil source quality impacted soil respiration significantly. With the predicted warming climate in the Caribbean, these tropical soils at high elevations are at risk of releasing sequestered carbon into the atmosphere.

  17. Experimental reproduction of beak atrophy and dwarfism syndrome by infection in cherry valley ducklings with a novel goose parvovirus-related parvovirus.

    Science.gov (United States)

    Chen, Hao; Dou, Yanguo; Tang, Yi; Zheng, Xiaoqiang; Niu, Xiaoyu; Yang, Jing; Yu, Xianglong; Diao, Youxiang

    2016-02-01

    Infection of clinically susceptible ducks, including cherry valley and Muscovy ducks, with a novel goose parvovirus (GPV)-related virus (N-GPV) can result in beak atrophy and dwarfism syndrome (BADS). To obtain new insights into the host range and pathogenic potential of this novel waterfowl parvovirus, cherry valley ducklings (n=20) were experimentally infected with N-GPV strain SDLC01. An equal number of ducklings served as uninfected controls. The appearance of clinical signs, histopathological changes, viral shedding, and seroconversion was monitored for 20 days post-infection. Infection status of all ducks was monitored using indirect ELISA, virus neutralization test, nested PCR, clinical indicators, and microscopic examination. Three ducks developed the typical clinical, gross, and histological changes of BADS. By study day 6, the infected ducks had seroconverted to N-GPV. The antibodies raised were neutralizing against the SDLC01 strain in vitro. Here we successfully developed an experimental infection model for studying the pathogenicity and role of N-GPV in BADS. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Contribution of Soil Fauna to Foliar Litter-Mass Loss in Winter in an Ecotone between Dry Valley and Montane Forest in the Upper Reaches of the Minjiang River.

    Science.gov (United States)

    Peng, Yan; Yang, Wanqin; Li, Jun; Wang, Bin; Zhang, Chuan; Yue, Kai; Wu, Fuzhong

    2015-01-01

    Litter decomposition during winter can provide essential nutrients for plant growth in the subsequent growing season, which plays important role in preventing the expansion of dry areas and maintaining the stability of ecotone ecosystems. However, limited information is currently available on the contributions of soil fauna to litter decomposition during winter in such ecosystems. Therefore, a field experiment that included litterbags with two different mesh sizes (0.04 mm and 3 mm) was conducted to investigate the contribution of soil fauna to the loss of foliar litter mass in winter from November 2013 to April 2014 along the upper reaches of the Minjiang River. Two litter types of the dominant species were selected in each ecosystem: cypress (Cupressus chengiana) and oak (Quercus baronii) in ecotone; cypress (Cupressus chengiana) and clovershrub (Campylotropis macrocarpa) in dry valley; and fir (Abies faxoniana) and birch (Betula albosinensis) in montane forest. Over one winter incubation, foliar litter lost 6.0%-16.1%, 11.4%-26.0%, and 6.4%-8.5% of initial mass in the ecotone, dry valley and montane forest, respectively. Soil fauna showed obvious contributions to the loss of foliar litter mass in all of the ecosystems. The highest contribution (48.5%-56.8%) was observed in the ecotone, and the lowest contribution (0.4%-25.8%) was observed in the montane forest. Compared with other winter periods, thawing period exhibited higher soil fauna contributions to litter mass loss in ecotone and dry valley, but both thawing period and freezing period displayed higher soil fauna contributions in montane forest. Statistical analysis demonstrated that the contribution of soil fauna was significantly correlated with temperature and soil moisture during the winter-long incubation. These results suggest that temperature might be the primary control factor in foliar litter decomposition, but more active soil fauna in the ecotone could contribute more in litter decomposition and

  19. Contribution of Soil Fauna to Foliar Litter-Mass Loss in Winter in an Ecotone between Dry Valley and Montane Forest in the Upper Reaches of the Minjiang River.

    Directory of Open Access Journals (Sweden)

    Yan Peng

    Full Text Available Litter decomposition during winter can provide essential nutrients for plant growth in the subsequent growing season, which plays important role in preventing the expansion of dry areas and maintaining the stability of ecotone ecosystems. However, limited information is currently available on the contributions of soil fauna to litter decomposition during winter in such ecosystems. Therefore, a field experiment that included litterbags with two different mesh sizes (0.04 mm and 3 mm was conducted to investigate the contribution of soil fauna to the loss of foliar litter mass in winter from November 2013 to April 2014 along the upper reaches of the Minjiang River. Two litter types of the dominant species were selected in each ecosystem: cypress (Cupressus chengiana and oak (Quercus baronii in ecotone; cypress (Cupressus chengiana and clovershrub (Campylotropis macrocarpa in dry valley; and fir (Abies faxoniana and birch (Betula albosinensis in montane forest. Over one winter incubation, foliar litter lost 6.0%-16.1%, 11.4%-26.0%, and 6.4%-8.5% of initial mass in the ecotone, dry valley and montane forest, respectively. Soil fauna showed obvious contributions to the loss of foliar litter mass in all of the ecosystems. The highest contribution (48.5%-56.8% was observed in the ecotone, and the lowest contribution (0.4%-25.8% was observed in the montane forest. Compared with other winter periods, thawing period exhibited higher soil fauna contributions to litter mass loss in ecotone and dry valley, but both thawing period and freezing period displayed higher soil fauna contributions in montane forest. Statistical analysis demonstrated that the contribution of soil fauna was significantly correlated with temperature and soil moisture during the winter-long incubation. These results suggest that temperature might be the primary control factor in foliar litter decomposition, but more active soil fauna in the ecotone could contribute more in litter

  20. Impacts of disturbance initiated by road construction in a subtropical cloud forest in the Luquillo Experimental Forest, Puerto Rico

    Science.gov (United States)

    Lydia P. Olander; F.N Scatena; Whendee L. Silver

    1998-01-01

    The impacts of road construction and the spread of exotic vegetation, which are common threats to upper elevation tropical forests, were evaluated in the subtropical cloud forests of Puerto Rico. The vegetation, soil and microclimate of 6-month-old road®lls, 35-year-old road®lls and mature forest with and without grass understories were compared. Recent road®lls had...

  1. Physiognomy and distribution of mountain meadows in an alpine valley over 150 years of spontaneous forest expansion

    Directory of Open Access Journals (Sweden)

    Sitzia T

    2012-02-01

    Full Text Available Through the classification of current and historical aerial photosbetween 1973 and 2006, we analysed the evolution of size, shape and connectivity of 59 mountain meadows (maggenghi of the Pejo district (Trentino, Northern Italy. The maggenghi are scattered patches within a forested matrix. We conducted the same analysis on an Austro-Hungarian cadastral map of 1859. The total surface covered by maggenghi was 137.4 ha in 1973, and decreased to 78.3 ha (57% in 2006. The mean shape and connectivity index in 1973 are significantly lower than those of 2006. Within a 1-km radius around the studied patches, woodlands increased by 7% in the same time range. Among the 25 maggenghi present in 1958, 12 has been subdivided into 39 smaller fragments and 13 has been reduced in their size without any fragmentation. A general process of meadow patches evolution which included area and connectivity reduction and shape simplification has been noticed. This process is common to many other alpine landscapes. The study of these processes is fundamental for policies aimed to conservation of mountain meadows, as well as to identify the single patches deserving conservation for their current and historical landscape structure, as many studies report their significant effects on local floristic diversity.

  2. Effects of forest management on running buffalo clover (Trifolium stoloniferum Muhl. Ex A. Eaton) distribution and abundance in the Fernow Experimental Forest

    Science.gov (United States)

    J.Q. Burkhart; J.R. Rentch; T.M. Schuler

    2013-01-01

    Identifying habitat preferences of species of concern is fundamental to the practice of conservation, but disturbances and other environmental processes can substantially affect suitability. Trifolium stoloniferum, or running buffalo clover, is a federally endangered plant species that occurs on the Fernow Experimental Forest in West Virginia....

  3. An experimental test of the causes of forest growth decline with stand age.

    Science.gov (United States)

    Michael G. Ryan; Dan Binkley; James H. Fownes; Christian Giardina; Randy S. Senock

    2004-01-01

    The decline in aboveground wood production after canopy closure in even-aged forest stands is a common pattern in forests, but clear evidence for the mechanism causing the decline is lacking. The problem is fundamental to forest biology, commercial forestry (the decline sets the rotation age), and to carbon storage in forests. We tested three hypotheses...

  4. Regeneration of five commercially-valuable tree species after experimental logging in an Amazonian forest

    Directory of Open Access Journals (Sweden)

    Lima Albertina Pimentel

    2002-01-01

    Full Text Available This study investigated the regeneration variation of five commercially valuable tree species in relation to different intensities of felling in fourteen 4-ha plots in an area under experimental forest management. This experiment was carried out in a typical Amazonian tropical forest sample on "terra-firme," in Manaus (AM. Plots were logged 7 and 8 years (1987 and 1988, or 3 years (1993 before the study. All trees with height greater than 2 m, and diameter at breast height (DBH smaller than 10 cm were measured. Only Aniba hostmanniana, Ocotea aciphylla, Licaria pachycarpa, Eschweilera coriacea and Goupia glabra were sufficiently common for individual analyses. These species have high timber values in the local market. Eight years after logging, the species responded differently to logging intensities. The numbers of individuals of Goupia glabra and Aniba hostmanniana were positively related to the intensity of logging, while Ocotea aciphylla, Licaria pachycarpa, and Eschweilera coriacea showed no statistically significant response. In the most recently (1993 logged areas, Goupia glabra and Aniba hostmanniana had higher numbers of individuals than the control plots.

  5. Forests and methane - at the intersection of science and politics, experimentation and extrapolation, objectivity and subjectivity

    International Nuclear Information System (INIS)

    Peyron, Jean-Luc

    2005-01-01

    According to recent information, vegetation is thought to be a major source of methane. This phenomenon had not been contemplated until now and still remains to be explained. According to the authors and on the basis of rough extrapolations, it may cast light on some missing pieces in the global methane balance. The initial reaction by commentators following this discovery was to discuss its consequences on the strategy to fight the greenhouse effect considering methane's considerable impact on global warming. However, a preliminary analysis based on opinions from a range of experts underscores three aspects - the experimental discovery needs to be confirmed and explained before drawing any hasty conclusions; extrapolations performed so far on a global scale are highly inadequate and probably overestimated; implications for fighting the greenhouse effect are limited because the phenomenon in question is a natural one and not extensive enough to offset the benefits of forests as a sink for carbon dioxide. (authors)

  6. Distribution, abundance and traditional management of Agave potatorum in the Tehuacán Valley, Mexico: bases for sustainable use of non-timber forest products.

    Science.gov (United States)

    Delgado-Lemus, América; Casas, Alejandro; Téllez, Oswaldo

    2014-09-03

    Agave species have been used for thousands of years in the Tehuacán Valley, but the current mescal production has great impact on populations of the most used species. Harvesting of A. potatorum takes place before sexual reproduction and the over-extraction put local populations at high risk. In the community of San Luis Atolotilán (SLA), mescal has been produced for one century but the growing mescal trade is leading to intensified agave extraction. Our study evaluated distribution and abundance of A. potatorum, extraction rates, management practices and economic importance for SLA households. The unbalanced relation between availability and extraction rates would be an indicator of risk requiring sustainable management strategies. Our case study aspires contributing to analyze general patterns for sustainable use for this and other forest products highly extracted. We used bioclimatic modeling to project a map of potential distribution of the species, and ecological sampling to estimate the total availability of harvestable agaves within the territory of SLA. We used participant observation, surveys and semi-structured interviews with producers and households of SLA to document agave uses, technological and socio-economic aspects of mescal production, and to estimate extraction rates of agaves. Mescal production, medicine and fodder are the most important uses of A. potatorum. Its distribution area is nearly 608 ha where annually occur on average 7,296 harvestable plants, nearly 54 to 87% of them being harvested. Mescal production currently is a non-sustainable activity, requiring great changes in patterns of extraction and management adopting sustainable criteria. Local people started management planning to ensure the future availability of agaves, and the ecological information of this study has been helpful in constructing their decisions. Technical support for improving local experiences for managing populations' recovering is a priority. Interaction of

  7. Experimental Forests and climate change: views of long-term employees on ecological change and the role of Experimental Forests and Ranges in understanding and adapting to climate change

    Science.gov (United States)

    Laurie Yung; Mason Bradbury; Daniel R. Williams

    2012-01-01

    In this project, we examined the views of 21 long-term employees on climate change in 14 Rocky Mountain Research Station Experimental Forests and Ranges (EFRs). EFRs were described by employees as uniquely positioned to advance knowledge of climate change impacts and adaptation strategies due to the research integrity they provide for long-term studies, the ability to...

  8. Invertebrates of The H.J. Andrews Experimental Forest, Western Cascades, Oregon: I. An annotated checklist of fleas.

    Science.gov (United States)

    Robert E. Lewis; Chris Maser

    1981-01-01

    During a trapping survey of small mammals (approximately 3,000 individuals), species of fleas (1,632 specimens) were collected in the H.J. Andrews Experimental Forest, Western Cascades, Oregon. Host mammals were represented by 15 species—6 insectivores and 9 rodents captured from June through September. The collections extend our knowledge of the fauna of Oregon.

  9. Invertebrates of the H.J. Andrews Experimental Forest, western Cascades, Oregon II. an annotated checklist of caddisflies (Trichoptera)

    Science.gov (United States)

    N.H. Anderson; G.M. Cooper; D.G Denning

    1982-01-01

    At least 99 species, representing 14 families of Trichoptera, are recorded from the H.J. Andrews Experimental Forest, near Blue River, Oregon. The collecting sites include a wide diversity of environmental conditions in a 6000-hectare watershed of the western Cascade Range (from 400 to 1 630 meters in altitude and from 1st- to 7th-order streams).

  10. Invertebrates of The H.J. Andrews Experimental Forest, Western Cascade Mountains, Oregon: IV. The Oribatid Mites (Acari: Cryptostigmata).

    Science.gov (United States)

    Andrew Moldenke; Becky. Fichter

    1988-01-01

    A fully illustrated key is presented for identifying genera of oribatid mites known from or suspected of occurring in the Pacific Northwest. The manual includes an introduction detailing sampling methodology; an illustrated glossary of all terminology used; two color plates of all taxa from the H. J. Andrews Experimental Forest; a diagrammatic key to the 16 major...

  11. Variation in nutrient characteristics of surface soils from the Luquillo Experimental Forest of Puerto Rico: A multivariate perspective.

    Science.gov (United States)

    S. B. Cox; M. R. Willig; F. N. Scatena

    2002-01-01

    We assessed the effects of landscape features (vegetation type and topography), season, and spatial hierarchy on the nutrient content of surface soils in the Luquillo Experimental Forest (LEF) of Puerto Rico. Considerable spatial variation characterized the soils of the LEF, and differences between replicate sites within each combination of vegetation type (tabonuco vs...

  12. Past and projected future changes in snowpack and soil frost at the Hubbard Brook Experimental Forest, New Hampshire, USA

    Science.gov (United States)

    John L. Campbell; Scott V. Ollinger; Gerald N. Flerchinger; Haley Wicklein; Katharine Hayhoe; Amey S. Bailey

    2010-01-01

    Long-term data from the Hubbard Brook Experimental Forest in New Hampshire show that air temperature has increased by about 1 °C over the last half century. The warmer climate has caused significant declines in snow depth, snow water equivalent and snow cover duration. Paradoxically, it has been suggested that warmer air temperatures may result in colder soils...

  13. Overview of the Manitou Experimental Forest Observatory: Site description and selected science results from 2008 to 2013

    Science.gov (United States)

    J. Ortega; A. Turnipseed; A. B. Guenther; T. G. Karl; D. A. Day; D. Gochis; J. A. Huffman; A. J. Prenni; E. J. T. Levin; S. M. Kreidenweis; P. J. DeMott; Y. Tobo; E. G. Patton; A. Hodzic; Y. Y. Cui; P. C. Harley; R. S. Hornbrook; E. C. Apel; R. K. Monson; A. S. D. Eller; J. P. Greenberg; M. C. Barth; P. Campuzano-Jost; B. B. Palm; J. L. Jimenez; A. C. Aiken; M. K. Dubey; C. Geron; J. Offenberg; M. G. Ryan; P. J. Fornwalt; S. C. Pryor; F. N. Keutsch; J. P. DiGangi; A. W. H. Chan; A. H. Goldstein; G. M. Wolfe; S. Kim; L. Kaser; R. Schnitzhofer; A. Hansel; C. A. Cantrell; R. L. Mauldin; J. N. Smith

    2014-01-01

    The Bio-hydro-atmosphere interactions of Energy, Aerosols, Carbon, H2O, Organics and Nitrogen (BEACHON) project seeks to understand the feedbacks and interrelationships between hydrology, biogenic emissions, carbon assimilation, aerosol properties, clouds and associated feedbacks within water-limited ecosystems. The Manitou Experimental Forest Observatory (MEFO) was...

  14. Fuel treatment effects on soil chemistry and foliar physiology of three coniferous species at the Teakettle Experimental Forest, California, USA

    Science.gov (United States)

    Rakesh Minocha; Swathi A. Turlapati; Stephanie Long; Malcolm. North

    2013-01-01

    A full factorial design crossing overstory (O) and understory (U) thinning and prescribed burning (B) was started at Teakettle Experimental Forest, California, in 2001 with the aim of achieving shifts in species composition to favor fire-resistant pines over fir. The goal of the present study was to evaluate the use of metabolic changes as early indicators for...

  15. Northern Rocky Mountain experimental forests: Settings for science, management, and education alliances

    Science.gov (United States)

    Theresa B. Jain; Michael A. Battaglia; Russell T. Graham

    2014-01-01

    Society's view of forests and what they produce changed considerably during the latter part of the 20th century. Prior to the 1970s, society believed that forests in the western United States provided a seemingly infinite supply of natural resources and economic prosperity. The public trusted experts to make forest management decisions dedicated to resource...

  16. Culvert flow in small drainages in montane tropical forests: observations from the Luquillo Experimental Forest of Puerto Rico.

    Science.gov (United States)

    F. N. Scatena

    1990-01-01

    This paper describe the hydraulics of unsubmerged flow for 5 culverts in the Luiquillo Esperimental Forest of Puerto Rico. A General equation based on empirical data is presented to estimate culvert discharge during unsubmerged conditions. Large culverts are needed in humid tropical montane areas than in humid temperatute watersheds and are usually appropriate only...

  17. Changing forest water yields in response to climate warming: results from long-term experimental watershed sites across North America

    Science.gov (United States)

    Creed, Irena F; Spargo, Adam T; Jones, Julia A; Buttle, Jim M; Adams, Mary B; Beall, Fred D; Booth, Eric G; Campbell, John L; Clow, Dave; Elder, Kelly; Green, Mark B; Grimm, Nancy B; Miniat, Chelcy; Ramlal, Patricia; Saha, Amartya; Sebestyen, Stephen; Spittlehouse, Dave; Sterling, Shannon; Williams, Mark W; Winkler, Rita; Yao, Huaxia

    2014-01-01

    Climate warming is projected to affect forest water yields but the effects are expected to vary. We investigated how forest type and age affect water yield resilience to climate warming. To answer this question, we examined the variability in historical water yields at long-term experimental catchments across Canada and the United States over 5-year cool and warm periods. Using the theoretical framework of the Budyko curve, we calculated the effects of climate warming on the annual partitioning of precipitation (P) into evapotranspiration (ET) and water yield. Deviation (d) was defined as a catchment's change in actual ET divided by P [AET/P; evaporative index (EI)] coincident with a shift from a cool to a warm period – a positive d indicates an upward shift in EI and smaller than expected water yields, and a negative d indicates a downward shift in EI and larger than expected water yields. Elasticity was defined as the ratio of interannual variation in potential ET divided by P (PET/P; dryness index) to interannual variation in the EI – high elasticity indicates low d despite large range in drying index (i.e., resilient water yields), low elasticity indicates high d despite small range in drying index (i.e., nonresilient water yields). Although the data needed to fully evaluate ecosystems based on these metrics are limited, we were able to identify some characteristics of response among forest types. Alpine sites showed the greatest sensitivity to climate warming with any warming leading to increased water yields. Conifer forests included catchments with lowest elasticity and stable to larger water yields. Deciduous forests included catchments with intermediate elasticity and stable to smaller water yields. Mixed coniferous/deciduous forests included catchments with highest elasticity and stable water yields. Forest type appeared to influence the resilience of catchment water yields to climate warming, with conifer and deciduous catchments more susceptible to

  18. Effect of subalpine canopy removal on snowpack, soil solution, and nutrient export, Fraser Experimental Forest, CO

    Science.gov (United States)

    Stottlemyer, R.; Troendle, C.A.

    1999-01-01

    Research on the effects of vegetation manipulation on snowpack, soil water, and streamwater chemistry and flux has been underway at the Fraser Experimental Forest (FEF), CO, since 1982. Greater than 95% of FEF snowmelt passes through watersheds as subsurface flow where soil processes significantly alter meltwater chemistry. To better understand the mechanisms accounting for annual variation in watershed streamwater ion concentration and flux with snowmelt, we studied subsurface water flow, its ion concentration, and flux in conterminous forested and clear cut plots. Repetitive patterns in subsurface flow and chemistry were apparent. Control plot subsurface flow chemistry had the highest ion concentrations in late winter and fall. When shallow subsurface flow occurred, its Ca2+, SO42-, and HCO3- concentrations were lower and K+ higher than deep flow. The percentage of Ca2+, NO3-, SO42-, and HCO3- flux in shallow depths was less and K+ slightly greater than the percentage of total flow. Canopy removal increased precipitation reaching the forest floor by about 40%, increased peak snowpack water equivalent (SWE) > 35%, increased the average snowpack Ca2+, NO3-, and NH4+ content, reduced the snowpack K+ content, and increased the runoff four-fold. Clear cutting doubled the percentage of subsurface flow at shallow depths, and increased K+ concentration in shallow subsurface flow and NO3- concentrations in both shallow and deep flow. The percentage change in total Ca2+, SO42-, and HCO3- flux in shallow depths was less than the change in water flux, while that of K+ and NO3- flux was greater. Relative to the control, in the clear cut the percentage of total Ca2+ flux at shallow depths increased from 5 to 12%, SO42- 5.4 to 12%, HCO3- from 5.6 to 8.7%, K+ from 6 to 35%, and NO3- from 2.7 to 17%. The increases in Ca2+ and SO42- flux were proportional to the increase in water flux, the flux of HCO3- increased proportionally less than water flux, and NO3- and K+ were

  19. Hydrologic and forest management controls on DOC dynamics in the small watersheds of the H.J. Andrews Experimental Forest, OR

    Science.gov (United States)

    Lajtha, K.; Jones, J. A.

    2016-12-01

    Dissolved organic carbon (DOC) export from hillslopes to streams is an important component of the carbon cycle of a catchment and may be a critical source of energy for the aquatic food web in receiving waters. Using a long-term record of DOC and other dissolved nutrients and elements from paired watersheds from the H.J. Andrews Experimental Forest in Oregon, we explored hydrologic, climatic, and land-use controls on seasonal and inter-annual patterns of DOC flux in a seasonally dry ecosystem. Seasonal patterns of DOC flux demonstrated source limitations to DOC export, with DOC concentrations highest immediately following the first rains after a dry summer, and lowest after winter rains. In contrast, more geochemically-controlled elements showed simple dilution-concentration patterns with no seasonal hysteresis. Inter-annual patterns of DOC flux, however, did not provide evidence of source limitation, with DOC flux within a watershed tightly correlated to total discharge but not temperature. Among watersheds, forest harvest, even over 50 years ago, significantly reduced DOC flux but not fluxes of other elements including N; this response was linked to the loading of coarse woody debris to the forest floor. Chemical fingerprinting of DOC revealed that old-growth watersheds had higher fluxes of DOC characteristic of forest floor organic materials, likely delivered to streams through more surficial preferential flow pathways not subject to microbial alteration, respiration, or sorption losses. Taken together these results suggest that the biogeochemical composition of forested streams reflects both current hydrologic patterns and also processes that occurred many decades ago within the catchment.

  20. Negative responses of Collembola in a forest soil (Alptal, Switzerland) under experimentally increased N deposition

    International Nuclear Information System (INIS)

    Xu Guoliang; Schleppi, Patrick; Li Maihe; Fu Shenglei

    2009-01-01

    The response of specific groups of organisms, like Collembola to atmospheric nitrogen (N) deposition is still scarcely known. We investigated the Collembola community in a subalpine forest (Alptal, Switzerland) as subjected for 12 years to an experimentally increased N deposition (+25 on top of ambient 12 kg N ha -1 year -1 ). In the 0-5 cm soil layer, there was a tendency of total Collembola densities to be lower in N-treated than in control plots. The density of Isotomiella minor, the most abundant species, was significantly reduced by the N addition. A tendency of lower Collembola group richness was observed in N-treated plots. The Density-Group index (d DG ) showed a significant reduction of community diversity, but the Shannon-Wiener index (H') was not significantly affected by the N addition. The Collembola community can be considered as a bioindicator of N inputs exceeding the biological needs, namely, soil N saturation. - Collembola community, which was significantly affected by a long-term N addition experiment, can be considered as a bioindicator of N saturation.

  1. Negative responses of Collembola in a forest soil (Alptal, Switzerland) under experimentally increased N deposition

    Energy Technology Data Exchange (ETDEWEB)

    Xu Guoliang, E-mail: xugl@scbg.ac.c [Institute of Ecology, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650 (China); Schleppi, Patrick; Li Maihe [Swiss Federal Institute for Forest, Snow and Landscape Research, CH-8903 Birmensdorf (Switzerland); Fu Shenglei, E-mail: sfu@scib.ac.c [Institute of Ecology, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650 (China)

    2009-07-15

    The response of specific groups of organisms, like Collembola to atmospheric nitrogen (N) deposition is still scarcely known. We investigated the Collembola community in a subalpine forest (Alptal, Switzerland) as subjected for 12 years to an experimentally increased N deposition (+25 on top of ambient 12 kg N ha{sup -1} year{sup -1}). In the 0-5 cm soil layer, there was a tendency of total Collembola densities to be lower in N-treated than in control plots. The density of Isotomiella minor, the most abundant species, was significantly reduced by the N addition. A tendency of lower Collembola group richness was observed in N-treated plots. The Density-Group index (d{sub DG}) showed a significant reduction of community diversity, but the Shannon-Wiener index (H') was not significantly affected by the N addition. The Collembola community can be considered as a bioindicator of N inputs exceeding the biological needs, namely, soil N saturation. - Collembola community, which was significantly affected by a long-term N addition experiment, can be considered as a bioindicator of N saturation.

  2. Soil respiration patterns in root gaps 27 years after small scale experimental disturbance in Pinus contorta forests

    Science.gov (United States)

    Baker, S.; Berryman, E.; Hawbaker, T. J.; Ewers, B. E.

    2015-12-01

    While much attention has been focused on large scale forest disturbances such as fire, harvesting, drought and insect attacks, small scale forest disturbances that create gaps in forest canopies and below ground root and mycorrhizal networks may accumulate to impact regional scale carbon budgets. In a lodgepole pine (Pinus contorta) forest near Fox Park, WY, clusters of 15 and 30 trees were removed in 1988 to assess the effect of tree gap disturbance on fine root density and nitrogen transformation. Twenty seven years later the gaps remain with limited regeneration present only in the center of the 30 tree plots, beyond the influence of roots from adjacent intact trees. Soil respiration was measured in the summer of 2015 to assess the influence of these disturbances on carbon cycling in Pinus contorta forests. Positions at the centers of experimental disturbances were found to have the lowest respiration rates (mean 2.45 μmol C/m2/s, standard error 0.17 C/m2/s), control plots in the undisturbed forest were highest (mean 4.15 μmol C/m2/s, standard error 0.63 C/m2/s), and positions near the margin of the disturbance were intermediate (mean 3.7 μmol C/m2/s, standard error 0.34 C/m2/s). Fine root densities, soil nitrogen, and microclimate changes were also measured and played an important role in respiration rates of disturbed plots. This demonstrates that a long-term effect on carbon cycling occurs when gaps are created in the canopy and root network of lodgepole forests.

  3. Valley Fever

    Science.gov (United States)

    ... valley fever. These fungi are commonly found in soil in specific regions. The fungi's spores can be stirred into the air by ... species have a complex life cycle. In the soil, they grow as a mold with long filaments that break off into airborne ...

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

    Science.gov (United States)

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

    2011-01-01

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

  5. Experimental forest watershed studies contribution to the effect of disturbances on water quality

    Science.gov (United States)

    Daniel G. Neary

    2012-01-01

    The most sustainable and best quality fresh water sources in the world originate in forested watersheds (Dissmeyer 2000, Brooks et al. 2003, Barten and Ernst 2004). The biological, chemical, and physical characteristics of forest soils are particularly well suited to delivering high quality water to streams, and moderating the climatic extremes which affect stream...

  6. Thinning shock and response to fertilizer less than expected in young Douglas-fir stand at Wind River Experimental Forest.

    Science.gov (United States)

    Dean S. DeBell; Constance A. Harrington; John. Shumway

    2002-01-01

    Three thinning treatments (thinned to 3.7 by 3.7 m, thinned to 4.3 by 4.3 m, and an unthinned control treatment with nominal spacing averaging 2.6 by 2.6 m) were installed in a 10-year-old Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) plantation growing on a low-quality site at the Wind River Experimental Forest in southwest Washington. Two...

  7. A 4-year record of sitka spruce and western hemlock seed fall on the Cascade Head Experimental Forest.

    Science.gov (United States)

    Robert H. Ruth; Carl M. Berntsen

    1955-01-01

    Four years' measurement of seed fall in the spruce-hemlock type on the Cascade Head Experimental Forest indicates that an ample supply of seed is distributed over clear-cut areas under staggered-setting cutting. The largest tract sampled was 81 acres; in spite of a seed crop failure in 1950, it received an average of 243,000 viable spruce and hemlock seeds per...

  8. Volume and weight characteristics of a typical Douglas-fir/ western larch stand, Coram Experimental Forest, Montana

    Science.gov (United States)

    Robert E. Benson; Joyce A. Schlieter

    1980-01-01

    An over-mature Douglas-fir/western larch stand on the Coram Experimental Forest in Montana averaged about 7,300 ft3/acre (511 rn3/ha) of wood over 3 inches (7.62 cm) in diameter, and an additional 57 tons/acre (128/ha) of fine material, before harvest. After logging, using three different cutting methods and four different levels of utilization, wood residues ranged...

  9. Annotated checklist and key to the species of amphibians and reptiles inhabiting the northern Peruvian dry forest along the Andean valley of the Marañón River and its tributaries.

    Science.gov (United States)

    Koch, Claudia; Venegas, Pablo J; Cruz, Roy Santa; BÖhme, Wolfgang

    2018-02-22

    A checklist of the amphibians and reptiles of 35 localities situated in the northern Peruvian dry forest valley of the Marañón River and its tributaries, containing 14 species of amphibians and 54 species of reptiles, is provided from data collected between July 2005 and April 2014 during several herpetological surveys and from the literature. Detailed accounts are given for each collected species containing morphometric and scalation data, information on natural history, comments regarding their distribution, the conservation status and key literature. Eleven new species were discovered and described during the survey period. At least five additional taxa might also represent new species but more field work and data collection are necessary to determine their status. For two snake species we provide the first country record and for 23 further species new departamental records are provided.

  10. Organic Matter Transformation in the Peat Column at Marcell Experimental Forest: Humification and Vertical Stratification

    Energy Technology Data Exchange (ETDEWEB)

    Tfaily, Malak [Florida State University, Tallahassee; Cooper, Bill [Florida State University, Tallahassee; Kostka, [Georgia Institute of Technology, Atlanta; Chanton, Patrick R [ORNL; Schadt, Christopher Warren [ORNL; Hanson, Paul J [ORNL; Iversen, Colleen M [ORNL; Chanton, Jeff P [ORNL

    2014-01-01

    A large-scale ecosystem manipulation (Spruce and Peatland Responses under Climatic and Environmental Change, SPRUCE) is being constructed in the Marcell Experimental Forest, Minnesota, USA, to determine the effects of climatic forcing on ecosystem processes in northern peatlands. Prior to the initiation of the manipulation, we characterized the solid-phase peat to a depth of 2 meters using a variety of techniques, including peat C:N ratios, 13C and 15N isotopic composition, Fourier Transform Infrared (FT IR), and 13C Nuclear Magnetic Resonance spectroscopy (13C NMR). FT IR determined peat humification-levels increased rapidly between and 75 cm, indicating a highly reactive zone. We observed a rapid drop in the abundance of O-alkyl-C, carboxyl-C, and other oxygenated functionalities within this zone and a concomitant increase in the abundance of alkyl- and nitrogen-containing compounds. Below 75-cm, minimal change was observed except that aromatic functionalities accumulated with depth. Incubation studies revealed the highest methane production rates and greatest CH4:CO2 ratios within this and 75 cm zone. Hydrology and surface vegetation played a role in belowground carbon cycling. Radiocarbon signatures of microbial respiration products in deeper porewaters resembled the signatures of dissolved organic carbon rather than solid phase peat, indicating that more recently photosynthesized organic matter fueled the bulk of subsurface microbial respiration. Oxygen-containing functionalities, especially O-alkyl-C, appear to serve as an excellent proxy for soil decomposition rate, and in addition should be a sensitive indicator of the response of the solid phase peat to the climatic manipulation.

  11. Organic matter transformation in the peat column at Marcell Experimental Forest: Humification and vertical stratification

    Science.gov (United States)

    Tfaily, Malak M.; Cooper, William T.; Kostka, Joel E.; Chanton, Patrick R.; Schadt, Christopher W.; Hanson, Paul J.; Iversen, Colleen M.; Chanton, Jeffrey P.

    2014-04-01

    We characterized peat decomposition at the Marcell Experimental Forest (MEF), Minnesota, USA, to a depth of 2 m to ascertain the underlying chemical changes using Fourier transform infrared (FT IR) and 13C nuclear magnetic resonance (NMR) spectroscopy) and related these changes to decomposition proxies C:N ratio, δ13C and δ15N, bulk density, and water content. FT IR determined that peat humification increased rapidly between 30 and 75 cm, indicating a highly reactive intermediate-depth zone consistent with changes in C:N ratio, δ13C and δ15N, bulk density, and water content. Peat decomposition at the MEF, especially in the intermediate-depth zone, is mainly characterized by preferential utilization of O-alkyl-C, carboxyl-C, and other oxygenated functionalities with a concomitant increase in the abundance of alkyl- and nitrogen-containing compounds. Below 75 cm, less change was observed but aromatic functionalities and lignin accumulated with depth. Significant correlations with humification indices, identified by FT IR spectroscopy, were found for C:N ratios. Incubation studies at 22°C revealed the highest methane production rates, greatest CH4:CO2 production ratios, and significant O-alkyl-C utilization within this 30 and 75 cm zone. Oxygen-containing functionalities, especially O-alkyl-C, appear to serve as excellent proxies for soil decomposition rate and should be a sensitive indicator of the response of the solid phase peat to increased temperatures caused by climate change and the field study manipulations that are planned to occur at this site. Radiocarbon signatures of microbial respiration products in deeper pore waters at the MEF resembled the signatures of more modern dissolved organic carbon rather than solid phase peat, indicating that recently photosynthesized organic matter fueled the bulk of subsurface microbial respiration. These results indicate that carbon cycling at depth at the MEF is not isolated from surface processes.

  12. Chlorination and dechlorination rates in a forest soil — A combined modelling and experimental approach

    Energy Technology Data Exchange (ETDEWEB)

    Montelius, Malin, E-mail: malin.montelius@liu.se [Department of Thematic Studies — Environmental Change, Linköping University, 581 83 Linköping (Sweden); Svensson, Teresia [Department of Thematic Studies — Environmental Change, Linköping University, 581 83 Linköping (Sweden); Lourino-Cabana, Beatriz [EDF, Laboratoire National d' Hydraulique et Environnement, 78401 Chatou (France); Thiry, Yves [Andra, Research and Development Division, Parc de la Croix Blanche, 1/7 rue Jean Monnet, 92298 Châtenay-Malabry Cedex (France); Bastviken, David [Department of Thematic Studies — Environmental Change, Linköping University, 581 83 Linköping (Sweden)

    2016-06-01

    Much of the total pool of chlorine (Cl) in soil consists of naturally produced organic chlorine (Cl{sub org}). The chlorination of bulk organic matter at substantial rates has been experimentally confirmed in various soil types. The subsequent fates of Cl{sub org} are important for ecosystem Cl cycling and residence times. As most previous research into dechlorination in soils has examined either single substances or specific groups of compounds, we lack information about overall bulk dechlorination rates. Here we assessed bulk organic matter chlorination and dechlorination rates in coniferous forest soil based on a radiotracer experiment conducted under various environmental conditions (additional water, labile organic matter, and ammonium nitrate). Experiment results were used to develop a model to estimate specific chlorination (i.e., fraction of Cl{sup −} transformed to Cl{sub org} per time unit) and specific dechlorination (i.e., fraction of Cl{sub org} transformed to Cl{sup −} per time unit) rates. The results indicate that chlorination and dechlorination occurred simultaneously under all tested environmental conditions. Specific chlorination rates ranged from 0.0005 to 0.01 d{sup −1} and were hampered by nitrogen fertilization but were otherwise similar among the treatments. Specific dechlorination rates were 0.01–0.03 d{sup −1} and were similar among all treatments. This study finds that soil Cl{sub org} levels result from a dynamic equilibrium between the chlorination and rapid dechlorination of some Cl{sub org} compounds, while another Cl{sub org} pool is dechlorinated more slowly. Altogether, this study demonstrates a highly active Cl cycling in soils. - Highlights: • Chlorination and dechlorination rates in soil were revealed by a radiotracer method. • Chlorination was hampered by nitrogen addition. • Both Cl{sup −} and many Cl{sub org} compounds are highly reactive in soils. • Some formed Cl{sub org} seem to be refractory.

  13. Chemistry of burning the forest floor during the FROSTFIRE experimental burn, interior Alaska, 1999

    Science.gov (United States)

    Harden, J.W.; Neff, J.C.; Sandberg, D.V.; Turetsky, M.R.; Ottmar, R.; Gleixner, G.; Fries, T.L.; Manies, K.L.

    2004-01-01

    Wildfires represent one of the most common disturbances in boreal regions, and have the potential to reduce C, N, and Hg stocks in soils while contributing to atmospheric emissions. Organic soil layers of the forest floor were sampled before and after the FROSTFIRE experimental burn in interior Alaska, and were analyzed for bulk density, major and trace elements, and organic compounds. Concentrations of carbon, nutrients, and several major and trace elements were significantly altered by the burn. Emissions of C, N, and Hg, estimated from chemical mass balance equations using Fe, Al, and Si as stable constituents, indicated that 500 to 900 g C and up to 0 to 4 ?? 10-4 g Hg/M2 were lost from the site. Calculations of nitrogen loss range from -4 to +6 g/m2 but were highly variable (standard deviation 19), with some samples showing increased N concentrations post-burn potentially from canopy ash. Noncombustible major nutrients such as Ca and K also were inherited from canopy ash. Thermogravimetry indicates a loss of thermally labile C and increase of lignin-like C in char and ash relative to unburned counterparts. Overall, atmospheric impacts of boreal fires include large emissions of C, N and Hg that vary greatly as a function of severe fire weather and its access to deep organic layers rich in C, N, and Hg. In terrestrial systems, burning rearranges the vertical distribution of nutrients in fuels and soils, the proximity of nutrients and permafrost to surface biota, and the chemical composition of soil including its nutrient and organic constituents, all of which impact C cycling. Copyright 2004 by the American Geophysical Union.

  14. Twenty-Five year (1982-2007) history of lodgepole pine dwarf mistletoe animal vectors and ethephon control on the Fraser Experimental Forest in Colorado

    Science.gov (United States)

    Thomas. Nicholls

    2009-01-01

    This is a summary of the 25-year history of studies of mammal and bird vectors of lodgepole pine dwarf mistletoe (Arceuthobium americanum), ethephon control of dwarf mistletoe, and the ecology of the most important dwarf mistletoe vector, the gray jay (Persisoreus canadensis), on the USDA Forest Service, Fraser Experimental Forest...

  15. Soil bacterial communities of a calcium-supplemented and a reference watershed at the Hubbard Brook Experimental Forest (HBEF), New Hampshire, USA

    Science.gov (United States)

    Ganapathi Sridevi; Rakesh Minocha; Swathi A. Turlapati; Katherine C. Goldfarb; Eoin L. Brodie; Louis S. Tisa; Subhash C. Minocha

    2012-01-01

    Soil Ca depletion because of acidic deposition-related soil chemistry changes has led to the decline of forest productivity and carbon sequestration in the northeastern USA. In 1999, acidic watershed (WS) 1 at the Hubbard Brook Experimental Forest (HBEF), NH, USA was amended with Ca silicate to restore soil Ca pools. In 2006, soil samples were collected from the Ca-...

  16. Long-term calcium addition increases growth release, wound closure, and health of sugar maple (Acer saccharum) trees at the Hubbard Brook Experimental Forest

    Science.gov (United States)

    Brett A. Huggett; Paul G. Schaberg; Gary J. Hawley; Christopher Eager

    2007-01-01

    We surveyed and wounded forest-grown sugar maple (Acer saccharum Marsh.) trees in a long-term, replicated Ca manipulation study at the Hubbard Brook Experimental Forest in New Hampshire, USA. Plots received applications of Ca (to boost Ca availability above depleted ambient levels) or A1 (to compete with Ca uptake and further reduce Ca availability...

  17. Point Counts of Birds in Bottomland Hardwood Forests of the Mississippi Alluvial Valley: Duration, Minimum Sample Size, and Points Versus Visits

    Science.gov (United States)

    Winston Paul Smith; Daniel J. Twedt; David A. Wiedenfeld; Paul B. Hamel; Robert P. Ford; Robert J. Cooper

    1993-01-01

    To compare efficacy of point count sampling in bottomland hardwood forests, duration of point count, number of point counts, number of visits to each point during a breeding season, and minimum sample size are examined.

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

    Science.gov (United States)

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

  19. Hydrogeomorphic linkages of sediment transport in headwater streams, Maybeso Experimental Forest, southeast Alaska

    Science.gov (United States)

    Gomi, Takashi; Sidle, Roy C.; Swanston, Douglas N.

    2004-03-01

    Hydrogemorphic linkages related to sediment transport in headwater streams following basin wide clear-cut logging on Prince of Wales Island, southeast Alaska, were investigated. Landslides and debris flows transported sediment and woody debris in headwater tributaries in 1961, 1979, and 1993. Widespread landsliding in 1961 and 1993 was triggered by rainstorms with recurrence intervals (24 h precipitation) of 7.0 years and 4.2 years respectively. Occurrence, distribution, and downstream effects of these mass movements were controlled by landform characteristics such as channel gradient and valley configuration. Landslides and channelized debris flows created exposed bedrock reaches, log jams, fans, and abandoned channels. The terminus of the deposits did not enter main channels because debris flows spread and thinned on the unconfined bottom of the U-shaped glaciated valley. Chronic sediment input to channels included surface erosion of exposed till (rain splash, sheet erosion, and freeze-thaw action) and bank failures. Bedload sediment transport in a channel impacted by 1993 landslides and debris flows was two to ten times greater and relatively finer compared with bedload transport in a young alder riparian channel that had last experienced a landslide and debris flow in 1961. Sediment transport and storage were influenced by regeneration of riparian vegetation, storage behind recruited woody debris, development of a streambed armour layer, and the decoupling of hillslopes and channels. Both spatial and temporal variations of sediment movement and riparian condition are important factors in understanding material transport within headwaters and through channel networks.

  20. Effect of Experimentally Manipulated Fire Regimes on the Response of Forests to Drought

    Science.gov (United States)

    Refsland, T. K.; Knapp, B.; Fraterrigo, J.

    2017-12-01

    Climate change is expected to increase drought stress in many forests and alter fire regimes. Fire can reduce tree density and thus competition for limited water, but the effects of changing fire regimes on forest productivity during drought remain poorly understood. We measured the annual ring-widths of adult oak (Quercus spp.) trees in Mark Twain National Forest, Missouri USA that experienced unburned, annual or periodic (every 4 years) surface fire treatments from 1951 - 2015. Severe drought events were identified using the BILJOU water balance model. We determined the effect of fire treatment on stand-level annual growth rates as well as stand-level resistance and resilience to drought, defined as the drought-induced reduction in growth and post-drought recovery in growth, respectively. During favorable wet years, annual and periodic fire treatments reduced annual growth rates by approximately 10-15% relative to unburned controls (P burned stands during favorable wet years was likely caused by increased nitrogen (N) limitation in burned plots. After 60 years of treatment, burned plots experienced 30% declines in total soil N relative to unburned plots. Our finding that drought resistance and resilience were similar across all treatments suggest that fire-driven reductions in stand density may have negligible effects on soil moisture availability during drought. Our results highlight that climate-fire interactions can have important long-term effects on forest productivity.

  1. The Entiat Experimental Forest: a unique opportunity to examine hydrologic response to wildfire.

    Science.gov (United States)

    Richard D. Woodsmith; Kellie B. Vache; Jeffrey J. McDonnell; Jan Seibert; J. David Helvey

    2007-01-01

    Water is generally regarded as the most important natural resource in the interior Columbia River basin (ICRB). Public agencies managing forested headwater source areas are under increasing pressure to document water quantity and quality, and the effects of background and anthropogenic disturbances that influence them. Fire is widely recognized as the primary...

  2. Development of second-growth northern hardwoods on Bartlett Experimental Forest - a 25-year record

    Science.gov (United States)

    William B. Leak

    1961-01-01

    Second-growth timber occupies more than one-third of the commercial northern hardwood forest land in New England. The origin of these stands - clearcutting, or land abandonment with or without fire - determined their present characteristics; they are essentially even-aged, with a high proportion of intolerant and intermediate species and many stems of sprout origin (...

  3. Fire spread probabilities for experimental beds composed of mixedwood boreal forest fuels

    Science.gov (United States)

    M.B. Dickinson; E.A. Johnson; R. Artiaga

    2013-01-01

    Although fuel characteristics are assumed to have an important impact on fire regimes through their effects on extinction dynamics, limited capabilities exist for predicting whether a fire will spread in mixedwood boreal forest surface fuels. To improve predictive capabilities, we conducted 347 no-wind, laboratory test burns in surface fuels collected from the mixed-...

  4. Experimental Evidence that Hemlock Mortality Enhances Carbon Stabilization in Southern Appalachian Forest Soils

    Science.gov (United States)

    Fraterrigo, J.; Ream, K.; Knoepp, J.

    2017-12-01

    Forest insects and pathogens (FIPs) can cause uncertain changes in forest carbon balance, potentially influencing global atmospheric carbon dioxide (CO2) concentrations. We quantified the effects of hemlock (Tsuga canadensis L. Carr.) mortality on soil carbon fluxes and pools for a decade following either girdling or natural infestation by hemlock woolly adelgid (HWA; Adelges tsugae) to improve mechanistic understanding of soil carbon cycling response to FIPs. Although soil respiration (Rsoil) was similar among reference plots and plots with hemlock mortality, both girdled and HWA-infested plots had greater activities of β-glucosidase, a cellulose-hydrolyzing extracellular enzyme, and decreased O-horizon mass and fine root biomass from 2005 to 2013. During this period, total mineral soil carbon accumulated at a higher rate in disturbed plots than in reference plots in both the surface (0-10 cm) and subsurface (10-30 cm); increases were predominantly in the mineral-associated fraction of the soil organic matter. In contrast, particulate organic matter carbon accrued slowly in surface soils and declined in the subsurface of girdled plots. δ13C values of this fraction demonstrate that particulate organic matter carbon in the surface soil has become more microbially processed over time, suggesting enhanced decomposition of organic matter in this pool. Together, these findings indicate that hemlock mortality and subsequent forest regrowth has led to enhanced soil carbon stabilization in southern Appalachian forests through the translocation of carbon from detritus and particulate soil organic matter pools to the mineral-associated organic matter pool. These findings have implications for ecosystem management and modeling, demonstrating that forests may tolerate moderate disturbance without diminishing soil carbon storage when there is a compensatory growth response by non-host trees.

  5. Evaluating the Impacts of Grassland Conversions to Experimental Forest on Groundwater Recharge in the Nebraska Sand Hills

    Science.gov (United States)

    Adane, Zablon A.

    The Nebraska Sand Hills grasslands provide the greatest groundwater recharge rates in the High Plains Aquifer. However, the grasslands and their ecological services have become vulnerable to land use change and degradation. This study used a series of field data to investigate the effects of grassland conversions to forest on recharge rates in a century-old experimental forest in the Sand Hills. The results show that the impact of grassland conversion on recharge was dependent on the species and plantation density. Estimated recharge rates beneath the dense plantations represent reductions of 86-94% relative to the native grassland. Results of 1H Nuclear Magnetic Resonance spectral analysis suggested that the surface soil organic carbon beneath pine plantations also contain up to 3 times the ratio of hydrophobic components than the native grasslands and may alter the soil hydraulic properties. This investigation further uncovered a previously overlooked feedback between the effect of soil organic carbon chemical shift generated by the ponderosa pine needle litter decomposition; namely that the alteration may have a link to reduced groundwater recharge rates. Thus, a global optimizer algorithm was used to estimate the effective soil hydraulic parameters from monthly soil moisture contents and recharge rates were then estimated through HYDRUS 1-D numerical modeling for grassland and pine forest soils. The impact of grassland conversion to pine was an overall reduction of groundwater recharge by nearly 100%. These outcomes highlight the significance of the grasslands for recharge, in the Sand Hills and the sustainability of the High Plains Aquifer.

  6. Dampening effects of long-term experimental drought on growth and mortality rates of a Holm oak forest.

    Science.gov (United States)

    Barbeta, Adrià; Ogaya, Romà; Peñuelas, Josep

    2013-10-01

    Forests respond to increasing intensities and frequencies of drought by reducing growth and with higher tree mortality rates. Little is known, however, about the long-term consequences of generally drier conditions and more frequent extreme droughts. A Holm oak forest was exposed to experimental rainfall manipulation for 13 years to study the effect of increasing drought on growth and mortality of the dominant species Quercus ilex, Phillyrea latifolia, and Arbutus unedo. The drought treatment reduced stem growth of A. unedo (-66.5%) and Q. ilex (-17.5%), whereas P. latifolia remained unaffected. Higher stem mortality rates were noticeable in Q. ilex (+42.3%), but not in the other two species. Stem growth was a function of the drought index of early spring in the three species. Stem mortality rates depended on the drought index of winter and spring for Q. ilex and in spring and summer for P. latifolia, but showed no relation to climate in A. unedo. Following a long and intense drought (2005-2006), stem growth of Q. ilex and P. latifolia increased, whereas it decreased in A. unedo. Q. ilex also enhanced its survival after this period. Furthermore, the effect of drought treatment on stem growth in Q. ilex and A. unedo was attenuated as the study progressed. These results highlight the different vulnerabilities of Mediterranean species to more frequent and intense droughts, which may lead to partial species substitution and changes in forest structure and thus in carbon uptake. The response to drought, however, changed over time. Decreased intra- and interspecific competition after extreme events with high mortality, together with probable morphological and physiological acclimation to drought during the study period, may, at least in the short term, buffer forests against drier conditions. The long-term effects of drought consequently deserve more attention, because the ecosystemic responses are unlikely to be stable over time.Nontechnical summaryIn this study, we

  7. Utilizing LiDAR Datasets From Experimental Watersheds to Advance Ecohydrological Understanding in Seasonally Snow-Covered Forests

    Science.gov (United States)

    Harpold, A. A.; Broxton, P. D.; Guo, Q.; Barlage, M. J.; Gochis, D. J.

    2014-12-01

    The Western U.S. is strongly reliant on snowmelt from forested areas for ecosystem services and downstream populations. The ability to manage water resources from snow-covered forests faces major challenges from drought, disturbance, and regional changes in climate. An exciting avenue for improving ecohydrological process understanding is Light Detection and Ranging (LiDAR) because the technology simultaneously observes topography, forest properties, and snow/ice at high-resolution (100 km2). The availability and quality of LiDAR datasets is increasing rapidly, however they remain under-utilized for process-based ecohydrology investigations. This presentation will illustrate how LiDAR datasets from the Critical Zone Observatory (CZO) network have been applied to advance ecohydrological understanding through direct empirical analysis, as well as model parameterization and verification. Direct analysis of the datasets has proved fruitful for pre- and post-disturbance snow distribution estimates and interpreting in-situ snow depth measurements across sites. In addition, we illustrate the potential value of LiDAR to parameterize and verify of physical models with two examples. First, we use LiDAR to parameterize a land surface model, Noah multi-parameterization (Noah-MP), to investigate the sensitivity of modeled water and energy fluxes to high-resolution forest information. Second, we present a Snow Physics and Laser Mapping (SnowPALM) model that is parameterized with LiDAR information at its native 1-m scale. Both modeling studies demonstrate the value of LiDAR for representing processes with greater fidelity. More importantly, the increased model fidelity led to different estimates of water and energy fluxes at larger, watershed scales. Creating a network of experimental watersheds with LiDAR datasets offers the potential to test theories and models in previously unexplored ways.

  8. Resistance to Two Heterologous Neurotropic Oncolytic Viruses, Semliki Forest Virus and Vaccinia Virus, in Experimental Glioma

    Science.gov (United States)

    Le Boeuf, Fabrice; Lemay, Chantal; De Silva, Naomi; Diallo, Jean-Simon; Cox, Julie; Becker, Michelle; Choi, Youngmin; Ananth, Abhirami; Sellers, Clara; Breton, Sophie; Roy, Dominic; Falls, Theresa; Brun, Jan; Hemminki, Akseli; Hinkkanen, Ari; Bell, John C.

    2013-01-01

    Attenuated Semliki Forest virus (SFV) may be suitable for targeting malignant glioma due to its natural neurotropism, but its replication in brain tumor cells may be restricted by innate antiviral defenses. We attempted to facilitate SFV replication in glioma cells by combining it with vaccinia virus, which is capable of antagonizing such defenses. Surprisingly, we found parenchymal mouse brain tumors to be refractory to both viruses. Also, vaccinia virus appears to be sensitive to SFV-induced antiviral interference. PMID:23221568

  9. Determining the impacts of experimental forest plantation on groundwater recharge in the Nebraska Sand Hills (USA) using chloride and sulfate

    Science.gov (United States)

    Adane, Z. A.; Gates, J. B.

    2015-02-01

    Although impacts of land-use changes on groundwater recharge have been widely demonstrated across diverse environmental settings, most previous research has focused on the role of agriculture. This study investigates recharge impacts of tree plantations in a century-old experimental forest surrounded by mixed-grass prairie in the Northern High Plains (Nebraska National Forest), USA. Recharge was estimated using solute mass balance methods from unsaturated zone cores beneath 10 experimental plots with different vegetation and planting densities. Pine and cedar plantation plots had uniformly lower moisture contents and higher solute concentrations than grasslands. Cumulative solute concentrations were greatest beneath the plots with the highest planting densities (chloride concentrations 225-240 % and sulfate concentrations 175-230 % of the grassland plot). Estimated recharge rates beneath the dense plantations (4-10 mm yr-1) represent reductions of 86-94 % relative to the surrounding native grassland. Relationships between sulfate, chloride, and moisture content in the area's relatively homogenous sandy soils confirm that the unsaturated zone solute signals reflect partitioning between drainage and evapotranspiration in this setting. This study is among the first to explore afforestation impacts on recharge beneath sandy soils and sulfate as a tracer of deep drainage.

  10. Comparison of the mineralogical effects of an experimental forest fire on a goethite/ferrihydrite soil with a topsoil that contains hematite, maghemite and goethite

    DEFF Research Database (Denmark)

    Nørnberg, Per; Vendelboe, Anders Lindblad; Gunnlaugsson, Haraldur Pall

    2009-01-01

    as the result of high temperature as found after forest fires. However, a body of evidence argues against these sites having been exposed to fire. In an attempt to get closer to an explanation of this Fe mineralogy, an experimental forest fire was produced. The results showed a clear mineralogical zonation down...... to 10 cm depth. This was not observed at the natural sites, which contained a mixture of goethite/ferrihydrite, hematite and maghemite down to 20 cm depth. The experimental forest fire left charcoal and ashes at the topsoil, produced high pH and decreased organic matter content, all of which...... is in contrast to the natural sites. The conclusion from this work is that the mineralogy of these sites is not consistent with exposure to forest fire, but may instead result from long-term transformation in a reducing environment, possibly involving microbiology....

  11. Frost and leaf-size gradients in forests: global patterns and experimental evidence.

    Science.gov (United States)

    Lusk, Christopher H; Clearwater, Michael J; Laughlin, Daniel C; Harrison, Sandy P; Prentice, Iain Colin; Nordenstahl, Marisa; Smith, Benjamin

    2018-05-16

    Explanations of leaf size variation commonly focus on water availability, yet leaf size also varies with latitude and elevation in environments where water is not strongly limiting. We provide the first conclusive test of a prediction of leaf energy balance theory that may explain this pattern: large leaves are more vulnerable to night-time chilling, because their thick boundary layers impede convective exchange with the surrounding air. Seedlings of 15 New Zealand evergreens spanning 12-fold variation in leaf width were exposed to clear night skies, and leaf temperatures were measured with thermocouples. We then used a global dataset to assess several climate variables as predictors of leaf size in forest assemblages. Leaf minus air temperature was strongly correlated with leaf width, ranging from -0.9 to -3.2°C in the smallest- and largest-leaved species, respectively. Mean annual temperature and frost-free period were good predictors of evergreen angiosperm leaf size in forest assemblages, but no climate variable predicted deciduous leaf size. Although winter deciduousness makes large leaves possible in strongly seasonal climates, large-leaved evergreens are largely confined to frost-free climates because of their susceptibility to radiative cooling. Evergreen leaf size data can therefore be used to enhance vegetation models, and to infer palaeotemperatures from fossil leaf assemblages. © 2018 The Authors New Phytologist © 2018 New Phytologist Trust.

  12. First experimental evidence for carbon starvation at warm temperatures in epiphytic orchids of tropical cloud forests

    Science.gov (United States)

    Hoch, Guenter; Roemer, Helena; Fioroni, Tiffany; Olmedo, Inayat; Kahmen, Ansgar

    2017-04-01

    Tropical cloud forests are among the most climate sensitive ecosystems world-wide. The lack of a strong seasonality and the additional dampening of temperature fluctuations by the omnipresence of clouds and fog produce year-round constant climatic conditions. With climate change the presence of clouds and fog is, however, predicted to be reduced. The disappearance of the cooling fog cover will have dramatic consequences for air temperatures, that are predicted to increase locally well over 5 °C by the end of the 21st century. Especially the large number of endemic epiphytic orchids in tropical cloud forests that contribute substantially to the biological diversity of these ecosystems, but are typically adapted to a very narrow climate envelope, are speculated to be very sensitive to the anticipated rise in temperature. In a phytotron experiment we investigated the effect of increasing temperatures on the carbon balance (gas-exchange and the carbon reserve household) of 10 epiphytic orchid species from the genera Dracula, native to tropical, South-American cloud forests. The orchids were exposed to three temperature treatments: i) a constant temperature treatment (23°C/13°C, day/night) simulating natural conditions, ii) a slow temperature ramp of +0.75 K every 10 days, and iii) a fast temperature ramp of +1.5 K every 10 days. CO2 leaf gas-exchanges was determined every 10 days, and concentrations of low molecular weight sugars and starch were analyses from leaf samples throughout the experiment. We found that increasing temperatures had only minor effects on day-time leaf respiration, but led to a moderate increase of respiration during night-time. In contrast to the rather minor effects of higher temperatures on respiration, there was a dramatic decline of net-photosynthesis above day-time temperatures of 29°C, and a complete stop of net-carbon uptake at 33°C in all investigated species. This high sensitivity of photosynthesis to warming was independent of the

  13. An experimental test of the habitat-amount hypothesis for saproxylic beetles in a forested region.

    Science.gov (United States)

    Seibold, Sebastian; Bässler, Claus; Brandl, Roland; Fahrig, Lenore; Förster, Bernhard; Heurich, Marco; Hothorn, Torsten; Scheipl, Fabian; Thorn, Simon; Müller, Jörg

    2017-06-01

    The habitat-amount hypothesis challenges traditional concepts that explain species richness within habitats, such as the habitat-patch hypothesis, where species number is a function of patch size and patch isolation. It posits that effects of patch size and patch isolation are driven by effects of sample area, and thus that the number of species at a site is basically a function of the total habitat amount surrounding this site. We tested the habitat-amount hypothesis for saproxylic beetles and their habitat of dead wood by using an experiment comprising 190 plots with manipulated patch sizes situated in a forested region with a high variation in habitat amount (i.e., density of dead trees in the surrounding landscape). Although dead wood is a spatio-temporally dynamic habitat, saproxylic insects have life cycles shorter than the time needed for habitat turnover and they closely track their resource. Patch size was manipulated by adding various amounts of downed dead wood to the plots (~800 m³ in total); dead trees in the surrounding landscape (~240 km 2 ) were identified using airborne laser scanning (light detection and ranging). Over 3 yr, 477 saproxylic species (101,416 individuals) were recorded. Considering 20-1,000 m radii around the patches, local landscapes were identified as having a radius of 40-120 m. Both patch size and habitat amount in the local landscapes independently affected species numbers without a significant interaction effect, hence refuting the island effect. Species accumulation curves relative to cumulative patch size were not consistent with either the habitat-patch hypothesis or the habitat-amount hypothesis: several small dead-wood patches held more species than a single large patch with an amount of dead wood equal to the sum of that of the small patches. Our results indicate that conservation of saproxylic beetles in forested regions should primarily focus on increasing the overall amount of dead wood without considering its

  14. Stream invertebrate productivity linked to forest subsidies: 37 stream-years of reference and experimental data.

    Science.gov (United States)

    Wallace, J Bruce; Eggert, Susan L; Meyer, Judy L; Webster, Jackson R

    2015-05-01

    Riparian habitats provide detrital subsidies of varying quantities and qualities to recipient ecosystems. We used long-term data from three reference streams (covering 24 stream-years) and 13-year whole-stream organic matter manipulations to investigate the influence of terrestrial detrital quantity and quality on benthic invertebrate community structure, abundance, biomass, and secondary production in rockface (RF) and mixed substrates (MS) of forested headwater streams. Using a mesh canopy covering the entire treatment stream, we examined effects of litter ex'clusion, small- and large-wood removal, and addition of artificial wood (PVC) and leaves of varying quality on organic matter standing crops and invertebrate community structure and function. We assessed differences in functional feeding group distribution between substrate types as influenced by organic matter manipulations and long-term patterns of predator and prey production in manipulated vs. reference years. Particulate organic matter standing crops in MS of the treatment stream declined drastically with each successive year of litter exclusion, approaching zero after three years. Monthly invertebrate biomass and annual secondary production was positively related to benthic organic matter in the MS habitats. Rockface habitats exhibited fewer changes than MS habitats across all organic matter manipulations. With leaf addition, the patterns of functional group distribution among MS and RF habitats returned to patterns seen in reference streams. Secondary production per unit organic matter standing crop was greatest for the leaf addition period, followed by the reference streams, and significantly less for the litter exclusion and wood removal periods. These data indicate that the limited organic matter remaining in the stream following litter exclusion and wood removal was more refractory than that in the reference streams, whereas the added leaf material was more labile and readily converted into

  15. Distinct responses of soil respiration to experimental litter manipulation in temperate woodland and tropical forest.

    Science.gov (United States)

    Bréchet, Laëtitia M; Lopez-Sangil, Luis; George, Charles; Birkett, Ali J; Baxendale, Catherine; Castro Trujillo, Biancolini; Sayer, Emma J

    2018-04-01

    Global change is affecting primary productivity in forests worldwide, and this, in turn, will alter long-term carbon (C) sequestration in wooded ecosystems. On one hand, increased primary productivity, for example, in response to elevated atmospheric carbon dioxide (CO 2 ), can result in greater inputs of organic matter to the soil, which could increase C sequestration belowground. On other hand, many of the interactions between plants and microorganisms that determine soil C dynamics are poorly characterized, and additional inputs of plant material, such as leaf litter, can result in the mineralization of soil organic matter, and the release of soil C as CO 2 during so-called "priming effects". Until now, very few studies made direct comparison of changes in soil C dynamics in response to altered plant inputs in different wooded ecosystems. We addressed this with a cross-continental study with litter removal and addition treatments in a temperate woodland (Wytham Woods) and lowland tropical forest (Gigante forest) to compare the consequences of increased litterfall on soil respiration in two distinct wooded ecosystems. Mean soil respiration was almost twice as high at Gigante (5.0 μmol CO 2  m -2  s -1 ) than at Wytham (2.7 μmol CO 2  m -2  s -1 ) but surprisingly, litter manipulation treatments had a greater and more immediate effect on soil respiration at Wytham. We measured a 30% increase in soil respiration in response to litter addition treatments at Wytham, compared to a 10% increase at Gigante. Importantly, despite higher soil respiration rates at Gigante, priming effects were stronger and more consistent at Wytham. Our results suggest that in situ priming effects in wooded ecosystems track seasonality in litterfall and soil respiration but the amount of soil C released by priming is not proportional to rates of soil respiration. Instead, priming effects may be promoted by larger inputs of organic matter combined with slower turnover rates.

  16. Experimental warming does not enhance soil respiration in a semiarid temperate forest-steppe ecosystem

    DEFF Research Database (Denmark)

    Lellei-Kovacs, E.; Kovacs-Lang, E.; Kalapos, T.

    2008-01-01

    are still limited. Soil respiration rate-measured monthly between April and November from 2003 to 2006-remained very low (0.09 - 1.53 mu mol CO2 m(-2) s(-1))in accordance with the moderate biological activity and low humus content of the nutrient poor, coarse sandy soil. Specific soil respiration rate...... ( calculated for unit soil organic matter content), however, was relatively high (0.36 - 7.92 mu mol CO g(-1) C(org)h(-1)) suggesting substrate limitation for soil biological activity. During the day, soil respiration rate was significantly lower at dawn than at midday, while seasonally clear temperature......The influence of simulated climate change on soil respiration was studied in a field experiment on 4 m x 5 m plots in the semiarid temperate Pannonian sand forest-steppe. This ecosystem type has low productivity and soil organic matter content, and covers large areas, yet data on soil carbon fluxes...

  17. Viñales Taxonomic Characterization and trophic groups of two communities of birds associated to semideciduos forests and vegetation of Pine-oak of the paths «Marvels of Viñales» and «Valley Ancón» in Viñales National Park

    Directory of Open Access Journals (Sweden)

    Miguel Cué Rivero

    2015-06-01

    Full Text Available The present work was carried out in the months of February to April 2009 in the semideciduos forest «Marvels of Viñales» and the formation pine-encino of the «Valley Ancón» of the Viñales National Park and it pursued as main objective to characterize the taxonomic composition and tropic groups tof two communities of birds associated to semideciduos forest and pine oak vegetation from both -. The method of circular parcels of fixed radio was used in 30 points of counts separated to 150 m one of another. There were detected a total of 44 species of birds (in the semideciduo and 42 in pine-oak contained in 9 orders and 18 families. They registered 23 trophic groups with prevalence of Insectivorous. The communities of birds of the formation of semideciduo forest of the path «Marvels of Viñales» and of the forest of pine oak of «Valley Ancón» presented differences in its taxonomic composition The communities of birds of both vegetable formations showed differences as for their trophiccomposition but so much in one as in other majority of birds consumers of insects and grains was observed.

  18. Microbial response of an acid forest soil to experimental soil warming

    Science.gov (United States)

    S.S. Arnold; I.J. Fernandez; L.E. Rustad; L.M. Zibilske

    1999-01-01

    Effects of increased soil temperature on soil microbial biomass and dehydrogenase activity were examined on organic (O) horizon material in a low-elevation spruce-fir ecosystem. Soil temperature was maintained at 5 °C above ambient during the growing season in the experimental plots, and soil temperature, moisture, microbial biomass, and dehydrogenase activity were...

  19. Relationships between structure of the tree component and environmental variables in a subtropical seasonal forest in the upper Uruguay River valley, Brazil

    Directory of Open Access Journals (Sweden)

    Máida Ariane de Mélo

    2013-12-01

    Full Text Available This study aimed to analyze relationships among the structure of the tree component, edaphic variables and canopy discontinuity along a toposequence in a seasonal upland (hillside forest in southern Brazil. Soil and vegetation were sampled in 25 plots of 20 × 20 m each. We described the vegetation in terms of structure, richness and diversity, as well as by species distribution patterns. We evaluated canopy continuity, determined sloping and calculated spatial coordinates. We applied partial canonical correspondence analysis (pCCA to determine whether species distribution correlated with environmental and spatial variables. We identified 1201 individuals belonging to 76 species within 30 families. The species with highest density and frequency were Gymnanthes concolor Spreng., Calyptranthes tricona D.Legrand, Eugenia moraviana O.Berg and Trichilia claussenii DC. The pCCAs indicated significant correlations with environmental and spatial variables. Sand content, boron content and soil density collectively explained 36.17% of the species matrix variation (total inertia, whereas the spatial variables x, y and xy² collectively explained 14.27%. The interaction between environmental and spatial variables explained nearly 4.5%. However, 45.05% remained unexplained, attributed to stochastic variation or unmeasured variables. Terrain morphology and canopy discontinuity had no apparent influence on richness, and changes in species distribution were correlated with sloping, which affects soil features and determines the directional distribution of some species.

  20. Invertebrates of The H.J. Andrews Experimental Forest, Western Cascade Range, Oregon. V: An Annotated List of Insects and Other Arthropods

    Science.gov (United States)

    Gary L. Parson; Gerasimos Cassis; Andrew R. Moldenke; John D. Lattin; Norman H. Anderson; Jeffrey C Miller; Paul Hammond; Timothy D. Schowalter

    1991-01-01

    An annotated list of species of insects and other arthropods that have been collected and studies on the H.J. Andrews Experimental forest, western Cascade Range, Oregon. The list includes 459 families, 2,096 genera, and 3,402 species. All species have been authoritatively identified by more than 100 specialists. Information is included on habitat type, functional group...

  1. Evaluation of climatic data, post-treatment water yield and snowpack differences between closed and open stands of lodgepole pine on Tenderfoot Creek Experimental Forest

    Science.gov (United States)

    Phillip E. Farnes; Katherine J. Hansen

    2002-01-01

    Data collection on Tenderfoot Creek Experimental Forest was initiated in 1992 and has expanded to the present time. A preliminary report was prepared to include data collection through the 1995 season (Farnes et aI, 1995). Some data was updated in Farnes et al, 1999. Since then, data has been collected but has not been edited, summarized or tabulated in electronic form...

  2. The Starkey databases: spatial-environmental relations of North American elk, mule deer, and cattle at the Starkey Experimental Forest and Range in northeastern Oregon.

    Science.gov (United States)

    John G. Kie; Alan A. Ager; Norman J. Cimon; Michael J. Wisdom; Mary M. Rowland; Priscilla K. Coe; Scott L. Findholt; Bruce K. Johnson; Martin. Vavra

    2004-01-01

    In the late 1980s, the Starkey Project was initiated to study interactions among North American elk (Cervus elaphus), mule deer (Odocoileus hemionus) and domestic cattle at Starkey Experimental Forest and Range (Starkey) in northeastern Oregon. As part of the Starkey Project, an automated radio telemetry system was developed to...

  3. Effects of development of a natural gas well and associated pipeline on the natural and scientific resources of the Fernow Experimental Forest

    Science.gov (United States)

    Mary Beth Adams; Pamela J. Edwards; W. Mark Ford; Joshua B. Johnson; Thomas M. Schuler; Melissa Thomas-Van Gundy; Frederica Wood

    2011-01-01

    Development of a natural gas well and pipeline on the Fernow Experimental Forest, WV, raised concerns about the effects on the natural and scientifi c resources of the Fernow, set aside in 1934 for long-term research. A case study approach was used to evaluate effects of the development. This report includes results of monitoring projects as well as observations...

  4. Invertebrates of The H.J. Andrews Experimental Forest, western Cascade Range, Oregon. V: An annotated list of insects and other arthropods.

    Science.gov (United States)

    Gary L. Parson; Gerasimos Cassis; Andrew R. Moldenke; John D. Lattin; Norman H. Anderson; Jeffrey C Miller; Paul Hammond; Timothy D. Schowalter

    1991-01-01

    An annotated list of species of insects and other arthropods that have been collected and studies on the H.J. Andrews Experimental forest, western Cascade Range, Oregon. The list includes 459 families, 2,096 genera, and 3,402 species. All species have been authoritatively identified by more than 100 specialists. Information is included on habitat type, functional group...

  5. Nitrate Leaching From a Mountain Forest Ecosystem with Gleysols Subjected to Experimentally Increased N Deposition

    International Nuclear Information System (INIS)

    Schleppi, Patrick; Hagedorn, Frank; Providoli, Isabelle

    2004-01-01

    Nitrate leaching was measured over seven years of nitrogen (N) addition in a paired-catchment experiment in Alptal, central Switzerland (altitude: 1200 m, bulk N deposition: 12 kg ha -1 a -1 ). Two forested catchments (1500 m 2 each) dominated by Picea abies) were delimited by trenches in the Gleysols. NH 4 NO 3 was added to one of the catchments using sprinklers. During the first year, the N addition was labelled with 15 N. Additionally, soil N transformations were studied in replicated plots. Pre-treatment NO 3 - -N leaching was 4 kg ha -1 a -1 from both catchments, and remained between 2.5 and 4.8 kg ha -1 a -1 in the control catchment. The first year of treatment induced an additional leaching of 3.1 kg ha -1 , almost 90% of which was labelled with 15 N, indicating that it did not cycle through the large N pools of the ecosystem (soil organic matter and plants). These losses partly correspond to NO 3 - from precipitation bypassing the soil due to preferential flow. During rain or snowmelt events, NO 3 - concentration peaks as the water table is rising, indicating flushing from the soil. Nitrification occurs temporarily along the water flow paths in the soil and can be the source of NO 3 - flushing. Its isotopic signature however, shows that this release mainly affects recently applied N, stored only between runoff events or up to a few weeks. At first, the ecosystem retained 90% of the added N (2/3 in the soil), but NO 3 - losses increased from 10 to 30% within 7 yr, indicating that the ecosystem became progressively N saturated

  6. Ecological Study of Periphytic Algal Community of Doodh Ganga and Khansha-Mansha Streams of Yusmarg Forests: A Health Resort of Kashmir Valley, India

    Directory of Open Access Journals (Sweden)

    Rafia Rashid

    2013-06-01

    Full Text Available The present study on Doodh Ganga and Khansha-Mansha streams of Yusmarg forests deals with the general ecological studies on periphytic algal community in terms of species composition and density. During the present investigation the periphytic algal community of Doodh Ganga and Khansha-Mansha streams were represented by 30 taxa which belonged to 4 major classes namely Bacillariophyceae (14, Chlorophyceae (11, Cyanophyceae (4 and Euglenophyceae (1. The most common periphytic species encountered across all the sites included Closterium sp., Zygnema sp., Amphora sp., Cymbella sp., Epithemia sp., Fragilaria sp., Navicula sp., Synedra sp., Tabellaria sp., Lyngbya sp. and Phormidium sp. Among the two streams, Doodh Ganga showed large number of taxa (45 and Khansha-Mansha was having 37 taxa of periphyton. Bacillariophyceae was the dominant group both in diversity and density and included 14 taxa contributing 57% of total periphytic algal population. Cyanophyceae forming the second dominant class was represented by 4 genera comprising 22% of the total periphytic algae .Chlorophyceae ranked third in its dominance pattern with 11 genera forming 20% of all the periphytic algae. Euglenophyceae was represented by only one species of Euglena sp. forming 1% of all the periphytic algae and found only at site 2 (Doodh Ganga downstream.Amongst the study sites the highest (5.69 value of Shannon Weiner Index was found at Doodh Ganga upstream while as lowest (4.38 at Khansha-Mansha downstream. The primary conclusion is that the streams, having crystal clear water, and are free from pollution as Chlorophyceae are better represented in both the streams. Further, as a result of less anthropogenic pressures the quality of water is fairly good.

  7. Overview of the Manitou Experimental Forest Observatory: site description and selected science results from 2008 to 2013

    Science.gov (United States)

    Ortega, J.; Turnipseed, A.; Guenther, A. B.; Karl, T. G.; Day, D. A.; Gochis, D.; Huffman, J. A.; Prenni, A. J.; Levin, E. J. T.; Kreidenweis, S. M.; DeMott, P. J.; Tobo, Y.; Patton, E. G.; Hodzic, A.; Cui, Y. Y.; Harley, P. C.; Hornbrook, R. S.; Apel, E. C.; Monson, R. K.; Eller, A. S. D.; Greenberg, J. P.; Barth, M. C.; Campuzano-Jost, P.; Palm, B. B.; Jimenez, J. L.; Aiken, A. C.; Dubey, M. K.; Geron, C.; Offenberg, J.; Ryan, M. G.; Fornwalt, P. J.; Pryor, S. C.; Keutsch, F. N.; DiGangi, J. P.; Chan, A. W. H.; Goldstein, A. H.; Wolfe, G. M.; Kim, S.; Kaser, L.; Schnitzhofer, R.; Hansel, A.; Cantrell, C. A.; Mauldin, R. L.; Smith, J. N.

    2014-06-01

    The Bio-hydro-atmosphere interactions of Energy, Aerosols, Carbon, H2O, Organics & Nitrogen (BEACHON) project seeks to understand the feedbacks and inter-relationships between hydrology, biogenic emissions, carbon assimilation, aerosol properties, clouds and associated feedbacks within water-limited ecosystems. The Manitou Experimental Forest Observatory (MEFO) was established in 2008 by the National Center for Atmospheric Research to address many of the BEACHON research objectives, and it now provides a fixed field site with significant infrastructure. MEFO is a mountainous, semi-arid ponderosa pine-dominated forest site that is normally dominated by clean continental air but is periodically influenced by anthropogenic sources from Colorado Front Range cities. This article summarizes the past and ongoing research activities at the site, and highlights some of the significant findings that have resulted from these measurements. These activities include - soil property measurements; - hydrological studies; - measurements of high-frequency turbulence parameters; - eddy covariance flux measurements of water, energy, aerosols and carbon dioxide through the canopy; - determination of biogenic and anthropogenic volatile organic compound emissions and their influence on regional atmospheric chemistry; - aerosol number and mass distributions; - chemical speciation of aerosol particles; - characterization of ice and cloud condensation nuclei; - trace gas measurements; and - model simulations using coupled chemistry and meteorology. In addition to various long-term continuous measurements, three focused measurement campaigns with state-of-the-art instrumentation have taken place since the site was established, and two of these studies are the subjects of this special issue: BEACHON-ROCS (Rocky Mountain Organic Carbon Study, 2010) and BEACHON-RoMBAS (Rocky Mountain Biogenic Aerosol Study, 2011).

  8. Overview of the Manitou Experimental Forest Observatory: site description and selected science results from 2008-2013

    Science.gov (United States)

    Ortega, J.; Turnipseed, A.; Guenther, A. B.; Karl, T. G.; Day, D. A.; Gochis, D.; Huffman, J. A.; Prenni, A. J.; Levin, E. J. T.; Kreidenweis, S. M.; DeMott, P. J.; Tobo, Y.; Patton, E. G.; Hodzic, A.; Cui, Y.; Harley, P. C.; Hornbrook, R. H.; Apel, E. C.; Monson, R. K.; Eller, A. S. D.; Greenberg, J. P.; Barth, M.; Campuzano-Jost, P.; Palm, B. B.; Jimenez, J. L.; Aiken, A. C.; Dubey, M. K.; Geron, C.; Offenberg, J.; Ryan, M. G.; Fornwalt, P. J.; Pryor, S. C.; Keutsch, F. N.; DiGangi, J. P.; Chan, A. W. H.; Goldstein, A. H.; Wolfe, G. M.; Kim, S.; Kaser, L.; Schnitzhofer, R.; Hansel, A.; Cantrell, C. A.; Mauldin, R. L., III; Smith, J. N.

    2014-01-01

    The Bio-hydro-atmosphere interactions of Energy, Aerosols, Carbon, H2O, Organics & Nitrogen (BEACHON) project seeks to understand the feedbacks and inter-relationships between hydrology, biogenic emissions, carbon assimilation, aerosol properties, clouds and associated feedbacks within water-limited ecosystems. The Manitou Experimental Forest Observatory (MEFO) was established in 2008 by the National Center for Atmospheric Research to address many of the BEACHON research objectives, and it now provides a fixed field site with significant infrastructure. MEFO is a mountainous, semi-arid ponderosa pine-dominated forest site that is normally dominated by clean continental air, but is periodically influenced by anthropogenic sources from Colorado Front Range cities. This article summarizes the past and ongoing research activities at the site, and highlights some of the significant findings that have resulted from these measurements. These activities include: - soil property measurements, - hydrological studies, - measurements of high-frequency turbulence parameters, - eddy covariance flux measurements of water, energy, aerosols and carbon dioxide through the canopy, - biogenic and anthropogenic volatile organic compound emissions and their influence on regional atmospheric chemistry, - aerosol number and mass distributions, - chemical speciation of aerosol particles, - characterization of ice and cloud condensation nuclei, - trace gas measurements, and - model simulations using coupled chemistry and meteorology. In addition to various long-term continuous measurement, three focused measurement campaigns with state-of-the-art instrumentation have taken place since the site was established, and two of these are the subjects of this special issue: BEACHON-ROCS (Rocky Mountain Organic Carbon Study, 2010) and BEACHON-RoMBAS (Rocky Mountain Biogenic Aerosol Study, 2011).

  9. Establishing a cause and effect relationship for ambient ozone exposure and tree growth in the forest: Progress and an experimental approach

    International Nuclear Information System (INIS)

    Manning, William J.

    2005-01-01

    Much has been written about the effects of ambient ozone on tree growth. Cause and effect has been established with seedlings in chambers. Results from multi-year studies with older tree seedlings, in open-top chambers, have been inconclusive, due to chamber effects. Extrapolation of results from chambers to trees in the forest is not possible. Predictive models for forest tree growth reductions caused by ozone have been developed, but not verified. Dendrochronological methods have been used to establish correlations between radial growth reductions in forest trees and ambient ozone exposure. The protective chemical ethylenediurea (EDU) has been used to protect tree seedlings from ozone injury. An experimental approach is advocated here that utilizes forest trees selected for sensitivity and non-sensitivity to ozone, dendrochronological methods, the protective chemical EDU, and monitoring data for ambient ozone, stomatal conductance, soil moisture potential, air temperature, PAR, etc. in long-term investigations to establish cause and effect relationships. - Progress is reviewed and an experimental approach is proposed to demonstrate a cause and effect relationship for ambient ozone and forest tree growth

  10. Despite Buffers, Experimental Forest Clearcuts Impact Amphibian Body Size and Biomass.

    Science.gov (United States)

    Veysey Powell, Jessica S; Babbitt, Kimberly J

    2015-01-01

    Forest buffers are a primary tool used to protect wetland-dependent wildlife. Though implemented widely, buffer efficacy is untested for most amphibian species. Consequently, it remains unclear whether buffers are sufficient for maintaining amphibian populations and if so, how wide buffers should be. We present evidence from a six-year, landscape-scale experiment testing the impacts of clearcutting, buffer width, and hydroperiod on body size and condition and biomass of breeding adults for two amphibian species at 11 vernal pools in the northeastern United States. We randomly assigned treatments (i.e., reference, 100m buffer, 30m buffer) across pools, clearcut to create buffers, and captured all spotted salamanders and wood frogs. Clearcuts strongly and negatively impacted size, condition, and biomass, but wider buffers mitigated effect magnitude and duration. Among recaptured individuals, for example, 30m-treatment salamanders were predicted to be about 9.5 mm shorter than, while 100m-treatment salamanders did not differ in length from, reference-treatment salamanders. Similarly, among recaptured frogs, mean length in the 30m treatment was predicted to decrease by about 1 mm/year, while in the 100m and reference treatments, length was time-invariant. Some, but not all, metrics recovered with time. For example, female new-captured and recaptured salamanders were predicted, respectively and on average, to weigh 4.5 and 7 g less in the 30m versus reference treatment right after the cut. While recaptured-female mass was predicted to recover by 9.5 years post-cut, new-captured-female mass did not recover. Hydroperiod was an important mediator: in the 100m treatment, cutting predominately affected pools that were stressed hydrologically. Overall, salamanders and female frogs were impacted more than male frogs. Our results highlight the importance of individualized metrics like body size, which can reveal sublethal effects and illuminate mechanisms by which habitat

  11. Despite Buffers, Experimental Forest Clearcuts Impact Amphibian Body Size and Biomass.

    Directory of Open Access Journals (Sweden)

    Jessica S Veysey Powell

    Full Text Available Forest buffers are a primary tool used to protect wetland-dependent wildlife. Though implemented widely, buffer efficacy is untested for most amphibian species. Consequently, it remains unclear whether buffers are sufficient for maintaining amphibian populations and if so, how wide buffers should be. We present evidence from a six-year, landscape-scale experiment testing the impacts of clearcutting, buffer width, and hydroperiod on body size and condition and biomass of breeding adults for two amphibian species at 11 vernal pools in the northeastern United States. We randomly assigned treatments (i.e., reference, 100m buffer, 30m buffer across pools, clearcut to create buffers, and captured all spotted salamanders and wood frogs. Clearcuts strongly and negatively impacted size, condition, and biomass, but wider buffers mitigated effect magnitude and duration. Among recaptured individuals, for example, 30m-treatment salamanders were predicted to be about 9.5 mm shorter than, while 100m-treatment salamanders did not differ in length from, reference-treatment salamanders. Similarly, among recaptured frogs, mean length in the 30m treatment was predicted to decrease by about 1 mm/year, while in the 100m and reference treatments, length was time-invariant. Some, but not all, metrics recovered with time. For example, female new-captured and recaptured salamanders were predicted, respectively and on average, to weigh 4.5 and 7 g less in the 30m versus reference treatment right after the cut. While recaptured-female mass was predicted to recover by 9.5 years post-cut, new-captured-female mass did not recover. Hydroperiod was an important mediator: in the 100m treatment, cutting predominately affected pools that were stressed hydrologically. Overall, salamanders and female frogs were impacted more than male frogs. Our results highlight the importance of individualized metrics like body size, which can reveal sublethal effects and illuminate mechanisms by

  12. Radial Growth Response of Black Spruce Stands Ten Years after Experimental Shelterwoods and Seed-Tree Cuttings in Boreal Forest

    Directory of Open Access Journals (Sweden)

    Miguel Montoro Girona

    2016-10-01

    Full Text Available Partial cutting is thought to be an alternative to achieve sustainable management in boreal forests. However, the effects of intermediate harvest intensity (45%–80% on growth remain unknown in black spruce (Picea mariana (Mill. B.S.P. stands, one of the most widely distributed boreal species with great commercial interest. In this study, we analysed the effect of three experimental shelterwood and one seed-tree treatments on tree radial growth in even-aged black spruce stands, 10 years after intervention. Our results show that radial growth response 8–10 years after cutting was 41% to 62% higher than in untreated plots, with stand structure, treatment, tree position relative to skidding trails, growth before cutting and time having significant interactions. The stand structure conditioned tree growth after cutting, being doubled in younger and denser stands. Tree spatial position had a pronounced effect on radial growth; trees at the edge of the skidding trails showed twice the increase in growth compared to interior trees. Dominant trees before cutting located close to the skidding trails manifested the highest growth response after cutting. This research suggests that the studied treatments are effective to enhance radial wood production of black spruce especially in younger stands, and that the edge effect must be considered in silvicultural management planning.

  13. Experimental benznidazole treatment of Trypanosoma cruzi II strains isolated from children of the Jequitinhonha Valley, Minas Gerais, Brazil, with Chagas disease

    Directory of Open Access Journals (Sweden)

    Jaquelline Carla Valamiel de Oliveira-Silva

    2015-02-01

    Full Text Available Trypanosoma cruzi strains from distinct geographic areas show differences in drug resistance and association between parasites genetic and treatment response has been observed. Considering that benznidazole (BZ can reduce the parasite burden and tissues damage, even in not cured animals and individuals, the goal is to assess the drug response to BZ of T. cruzi II strains isolated from children of the Jequitinhonha Valley, state of Minas Gerais, Brazil, before treatment. Mice infected and treated with BZ in both phases of infection were compared with the untreated and evaluated by fresh blood examination, haemoculture, polymerase chain reaction, conventional (ELISA and non-conventional (FC-ALTA serologies. In mice treated in the acute phase, a significant decrease in parasitaemia was observed for all strains. Positive parasitological and/or serological tests in animals treated during the acute and chronic (95.1-100% phases showed that most of the strains were BZ resistant. However, beneficial effect was demonstrated because significant reduction (p < 0.05% and/or suppression of parasitaemia was observed in mice infected with all strains (acute phase, associated to reduction/elimination of inflammation and fibrosis for two/eight strains. BZ offered some benefit, even in not cured animals, what suggest that BZ use may be recommended at least for recent chronic infection of the studied region.

  14. Historical trajectories and restoration strategies for the Mississippi River alluvial valley

    Science.gov (United States)

    Brice B. Hanberry; John M. Kabrick; Hong S. He; Brian J. Palik

    2012-01-01

    Unlike upland forests in the eastern United States, little research is available about the composition and structure of bottomland forests before Euro-American settlement. To provide a historical reference encompassing spatial variation for the Lower Mississippi River Alluvial Valley, we quantified forest types, species distributions, densities, and stocking of...

  15. Molecular identification of Armillaria gallica from the Niobrara Valley Preserve in Nebraska

    Science.gov (United States)

    Mee-Sook Kim; Ned B. Klopfenstein

    2011-01-01

    Armillaria isolates were collected from a unique forest ecosystem in the Niobrara Valley Preserve in Nebraska, USA, which comprises a glacial and early postglacial refugium in the central plains of North America. The isolates were collected from diverse forest trees representing a unique mixture of forest types. Combined methods of rDNA sequencing and flow cytometric...

  16. STUDY OF SOIL AND LEAF LITTER MICROBIAL FATTY ACID PROFILES IN TABONUCO FOREST IN THE LUQUILLO EXPERIMENTAL FOREST IN PUERTO RICO

    Science.gov (United States)

    The results of this study suggests that there are two significantly distinct microbial communities in the leaf litter and soil components of this tropical forest. Fungi are more abundant in the leaf litter while bacteria are more abundant in the soil.

  17. Experimental soil warming effects on C, N, and major element cycling in a low elevation spruce-fir forest soil

    Science.gov (United States)

    Lindsey E. Rustad; Ivan J. Fernandez; Stephanie Arnold

    1996-01-01

    The effect of global warming on north temperate and boreal forest soils has been the subject of much recent debate. These soils serve as major reservoirs for C, N, and other nutrients necessary for forest growth and productivity. Given the uncertainties in estimates of organic matter turnover rates and storage, it is unclear whether these soils will serve as short or...

  18. The effects of acute irradiation on a forest biogeocenosis: Experimental data, model and practical applications for accidental cases

    International Nuclear Information System (INIS)

    Alexakhin, R.M.; Karaban, R.T.; Prister, B.S.

    1994-01-01

    The effects of acute irradiations of a mixed pine and birch forest in spring and autumn with a high power point-type gamma radiation source (1180 TBq 137 Cs) have been described. Radiation dose relationships for numerous response reactions of woody and herbaceous plants (growth and development of organs of woody plants, cytogenetical, physiological and biochemical changes in trees, reproductive potential of plants, damage and dying off of the forest as a biogeocenosis on the whole) have been calculated. Post-radiation recovery of the forest was investigated. Changes involving the secondary reactions related to radiation damage and death of the trees are presented. A model for radiation damage of forests has been designed. Examples are given on the usage of this model in the description of radiation effects in forests in the event of accidental releases of radionuclides into environment

  19. Valley polarization in bismuth

    Science.gov (United States)

    Fauque, Benoit

    2013-03-01

    The electronic structure of certain crystal lattices can contain multiple degenerate valleys for their charge carriers to occupy. The principal challenge in the development of valleytronics is to lift the valley degeneracy of charge carriers in a controlled way. In bulk semi-metallic bismuth, the Fermi surface includes three cigar-shaped electron valleys lying almost perpendicular to the high symmetry axis known as the trigonal axis. The in-plane mass anisotropy of each valley exceeds 200 as a consequence of Dirac dispersion, which drastically reduces the effective mass along two out of the three orientations. According to our recent study of angle-dependent magnetoresistance in bismuth, a flow of Dirac electrons along the trigonal axis is extremely sensitive to the orientation of in-plane magnetic field. Thus, a rotatable magnetic field can be used as a valley valve to tune the contribution of each valley to the total conductivity. As a consequence of a unique combination of high mobility and extreme mass anisotropy in bismuth, the effect is visible even at room temperature in a magnetic field of 1 T. Thus, a modest magnetic field can be used as a valley valve in bismuth. The results of our recent investigation of angle-dependent magnetoresistance in other semi-metals and doped semiconductors suggest that a rotating magnetic field can behave as a valley valve in a multi-valley system with sizeable mass anisotropy.

  20. Evolution of a short-term study of lodgepole pine dwarf mistletoe vectors that turned into a long-term study of the remarkable gray jay on the Fraser Experimental Forest,Colorado, 1982-2009

    Science.gov (United States)

    Thomas H. Nicholls

    2014-01-01

    This is a summary of a 5-year short-term study that evolved into 28 years of long-term research on the US Department of Agriculture, Forest Service's Fraser Experimental Forest in Colorado. The study was begun in 1982 by Forest Service Research Scientists Thomas H. Nicholls and Frank G. Hawksworth to determine the importance of mammal and bird vectors in the long-...

  1. Greening Turner Valley

    International Nuclear Information System (INIS)

    Byfield, M.

    2010-01-01

    This article discussed remedial activities undertaken in the Turner Valley. Remedial action in the valley must satisfy the financial concerns of engineers and investors as well as the environmental concerns of residents and regulators. Natural gas production in the Turner Valley began in 1914. The production practices were harmful and wasteful. Soil and water pollution was not considered a problem until recently. The impacts of cumulative effects and other pollution hazards are now being considered as part of many oil and gas environmental management programs. Companies know it is cheaper and safer to prevent pollutants from being released, and more efficient to clean them up quickly. Oil and gas companies are also committed to remediating historical problems. Several factors have simplified remediation plans in the Turner Valley. Area real estate values are now among the highest in Alberta. While the valley residents are generally friendly to the petroleum industry, strong communication with all stakeholders in the region is needed. 1 fig.

  2. A VRML-Based Data Portal: Hydrology of the Hubbard Brook Experimental Forest and Mirror Lake Sub-Basin

    Science.gov (United States)

    Becker, M. W.; Bursik, M. I.; Schuetz, J. W.

    2001-05-01

    The Hubbard Brook Experimental Forest (HBEF) of Central New Hampshire has been a focal point for collaborative hydrologic research for over 40 years. A tremendous amount of data from this area is available through the internet and other sources, but is not organized in a manner that facilitates teaching of hydrologic concepts. The Mirror Lake Watershed Interactive Teaching Database is making hydrologic data from the HBEF and associated interactive problem sets available to upper-level and post-graduate university students through a web-based resource. Hydrologic data are offered via a three-dimensional VRML (Virtual Reality Modeling Language) interface, that facilitates viewing and retrieval in a spatially meaningful manner. Available data are mapped onto a topographic base, and hot spots representing data collection points (e.g. weirs) lead to time-series displays (e.g. hydrographs) that provide a temporal link to the spatially organized data. Associated instructional exercises are designed to increase understanding of both hydrologic data and hydrologic methods. A pedagogical module concerning numerical ground-water modeling will be presented as an example. Numerical modeling of ground-water flow involves choosing the combination of hydrogeologic parameters (e.g. hydraulic conductivity, recharge) that cause model-predicted heads to best match measured heads in the aquifer. Choosing the right combination of parameters requires careful judgment based upon knowledge of the hydrogeologic system and the physics of ground-water flow. Unfortunately, students often get caught up in the technical aspects and lose sight of the fundamentals when working with real ground-water software. This module provides exercises in which a student chooses model parameters and immediately sees the predicted results as a 3-D VRML object. VRML objects are based upon actual Modflow model results corresponding to the range of model input parameters available to the student. This way, the

  3. Does tree species richness attenuate the effect of experimental irrigation and drought on decomposition rate in young plantation forests?

    Science.gov (United States)

    Masudur Rahman, Md; Verheyen, Kris; Castagneyrol, Bastien; Jactel, Hervé; Carnol, Monique

    2017-04-01

    Expected changes in precipitation in Europe due to climate change are likely to affect soil organic matter (OM) transformation. In forests, increasing tree species diversity might modulate the effect of changed precipitation. We evaluated the effect of tree species richness on the decomposition and stabilization rate in combination with reduced precipitation (FORBIO, Belgium) and irrigation treatment (ORPHEE, southern France) in young (6-8 yr.) experimental plantations. The species richness were one to four in FORBIO and one to five in ORPHEE. Twenty four rainout shelters of 3 m × 3 m were built around oak and beech trees in FORBIO plantation to impose a reduced precipitation treatment, whereas four of the eight blocks (175 m×100 m) in ORPHEE plantation was subjected to irrigation treatment. These treatments resulted in about 4% less soil moisture in FORBIO and about 7% higher soil moisture in ORPHEE compared to control. Commercially available green and rooibos tea bags were buried in the soil at 5-7 cm depth to measure two decomposition indices, known as 'tea bag index' (TBI). These TBI are (i) decomposition rate (k) and (ii) stabilization rate (S). The results showed no species richness effect on TBI indices in both reduced precipitation and irrigation treatment. In FORBIO, reduced precipitation resulted in decreased k and increased S compared to control around the beech trees only. In ORPHEE, both k and S were higher in the irrigation treatment compared to control. Overall, TBI indices were higher in FORBIO than ORPHEE and this might be explained by the sandy soils and poor nutrient content at the ORPHEE site. These results suggest that OM decomposition rate may be slower in drier condition and OM stabilization rate may be slower or faster in drier condition, depending on the site quality. The absence of tree species effects on OM transformation indicates that tree species richness would not be able to modulate the effects of changed precipitation patterns in

  4. Tropical Andean Forests Are Highly Susceptible to Nutrient Inputs—Rapid Effects of Experimental N and P Addition to an Ecuadorian Montane Forest

    Science.gov (United States)

    Homeier, Jürgen; Hertel, Dietrich; Camenzind, Tessa; Cumbicus, Nixon L.; Maraun, Mark; Martinson, Guntars O.; Poma, L. Nohemy; Rillig, Matthias C.; Sandmann, Dorothee; Scheu, Stefan; Veldkamp, Edzo; Wilcke, Wolfgang; Wullaert, Hans; Leuschner, Christoph

    2012-01-01

    Tropical regions are facing increasing atmospheric inputs of nutrients, which will have unknown consequences for the structure and functioning of these systems. Here, we show that Neotropical montane rainforests respond rapidly to moderate additions of N (50 kg ha−1 yr−1) and P (10 kg ha−1 yr−1). Monitoring of nutrient fluxes demonstrated that the majority of added nutrients remained in the system, in either soil or vegetation. N and P additions led to not only an increase in foliar N and P concentrations, but also altered soil microbial biomass, standing fine root biomass, stem growth, and litterfall. The different effects suggest that trees are primarily limited by P, whereas some processes—notably aboveground productivity—are limited by both N and P. Highly variable and partly contrasting responses of different tree species suggest marked changes in species composition and diversity of these forests by nutrient inputs in the long term. The unexpectedly fast response of the ecosystem to moderate nutrient additions suggests high vulnerability of tropical montane forests to the expected increase in nutrient inputs. PMID:23071734

  5. Nematode community shifts in response to experimental warming and canopy conditions are associated with plant community changes in the temperate-boreal forest ecotone.

    Science.gov (United States)

    Thakur, Madhav Prakash; Reich, Peter B; Fisichelli, Nicholas A; Stefanski, Artur; Cesarz, Simone; Dobies, Tomasz; Rich, Roy L; Hobbie, Sarah E; Eisenhauer, Nico

    2014-06-01

    Global climate warming is one of the key forces driving plant community shifts, such as range shifts of temperate species into boreal forests. As plant community shifts are slow to observe, ecotones, boundaries between two ecosystems, are target areas for providing early evidence of ecological responses to warming. The role of soil fauna is poorly explored in ecotones, although their positive and negative effects on plant species can influence plant community structure. We studied nematode communities in response to experimental warming (ambient, +1.7, +3.4 °C) in soils of closed and open canopy forest in the temperate-boreal ecotone of Minnesota, USA and calculated various established nematode indices. We estimated species-specific coverage of understory herbaceous and shrub plant species from the same experimental plots and tested if changes in the nematode community are associated with plant cover and composition. Individual nematode trophic groups did not differ among warming treatments, but the ratio between microbial-feeding and plant-feeding nematodes increased significantly and consistently with warming in both closed and open canopy areas and at both experimental field sites. The increase in this ratio was positively correlated with total cover of understory plant species, perhaps due to increased predation pressure on soil microorganisms causing higher nutrient availability for plants. Multivariate analyses revealed that temperature treatment, canopy conditions and nematode density consistently shaped understory plant communities across experimental sites. Our findings suggest that warming-induced changes in nematode community structure are associated with shifts in plant community composition and productivity in the temperate-boreal forest ecotones.

  6. Experimental test of postfire management in pine forests: impact of salvage logging versus partial cutting and nonintervention on bird-species assemblages.

    Science.gov (United States)

    Castro, Jorge; Moreno-Rueda, Gregorio; Hódar, José A

    2010-06-01

    There is an intense debate about the effects of postfire salvage logging versus nonintervention policies on regeneration of forest communities, but scant information from experimental studies is available. We manipulated a burned forest area on a Mediterranean mountain to experimentally analyze the effect of salvage logging on bird-species abundance, diversity, and assemblage composition. We used a randomized block design with three plots of approximately 25 ha each, established along an elevational gradient in a recently burned area in Sierra Nevada Natural and National Park (southeastern Spain). Three replicates of three treatments differing in postfire burned wood management were established per plot: salvage logging, nonintervention, and an intermediate degree of intervention (felling and lopping most of the trees but leaving all the biomass). Starting 1 year after the fire, we used point sampling to monitor bird abundance in each treatment for 2 consecutive years during the breeding and winter seasons (720 censuses total). Postfire burned-wood management altered species assemblages. Salvage logged areas had species typical of open- and early-successional habitats. Bird species that inhabit forests were still present in the unsalvaged treatments even though trees were burned, but were almost absent in salvage-logged areas. Indeed, the main dispersers of mid- and late-successional shrubs and trees, such as thrushes (Turdus spp.) and the European Jay (Garrulus glandarius) were almost restricted to unsalvaged treatments. Salvage logging might thus hamper the natural regeneration of the forest through its impact on assemblages of bird species. Moreover, salvage logging reduced species abundance by 50% and richness by 40%, approximately. The highest diversity at the landscape level (gamma diversity) resulted from a combination of all treatments. Salvage logging may be positive for bird conservation if combined in a mosaic with other, less-aggressive postfire

  7. Fort Valley's early scientists: A legacy of distinction

    Science.gov (United States)

    Andrew J. Sanchez Meador; Susan D. Olberding

    2008-01-01

    When the Riordan brothers of Flagstaff, Arizona, asked Gifford Pinchot to determine why there was a deficit in ponderosa pine seedlings, neither party understood the historical significance of what they were setting in motion for the field of forest research. The direct result of that professional favor was the establishment of the Fort Valley Experiment Station (Fort...

  8. Fort Valley's early scientists: A legacy of distinction (P-53)

    Science.gov (United States)

    Andrew J. Sanchez Meador; Susan D. Olberding

    2008-01-01

    When the Riordan brothers of Flagstaff, Arizona asked Gifford Pinchot to determine why there was a deficit in ponderosa pine seedlings, neither party understood the historical significance of what they were setting in motion for the field of forest research. The direct result of that professional favor was the establishment of the Fort Valley Experiment Station (Fort...

  9. Severity of a mountain pine beetle outbreak across a range of stand conditions in Fraser Experimental Forest, Colorado, United States

    Science.gov (United States)

    Anthony G. Vorster; Paul H. Evangelista; Thomas J. Stohlgren; Sunil Kumar; Charles C. Rhoades; Robert M. Hubbard; Antony S. Cheng; Kelly Elder

    2017-01-01

    The recent mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreaks had unprecedented effects on lodgepole pine (Pinus contorta var. latifolia) in western North America. We used data from 165 forest inventory plots to analyze stand conditions that regulate lodgepole pine mortality across a wide range of stand structure and species composition at the Fraser...

  10. Persistence of Native Trees in an Invaded Hawaiian Lowland Wet Forest: Experimental Evaluation of Light and Water Constraints

    Science.gov (United States)

    Jodie R. Schulten; T. Colleen Cole; Susan Cordell; Keiko M. Publico; Rebecca Ostertag; Jaime E. Enoka; Jené D. Michaud

    2014-01-01

    Hawaiian lowland wet forests are heavily invaded and their restoration is most likely to be successful if native species selected for restoration have efficient resource-use traits. We evaluated growth, survival, and ecophysiological responses of four native and four invasive species in a greenhouse experiment that simulated reduced light and water conditions commonly...

  11. Effects of experimental fuel additions on fire intensity and severity: unexpected carbon resilience of a neotropical forest.

    Science.gov (United States)

    Brando, Paulo M; Oliveria-Santos, Claudinei; Rocha, Wanderley; Cury, Roberta; Coe, Michael T

    2016-07-01

    Global changes and associated droughts, heat waves, logging activities, and forest fragmentation may intensify fires in Amazonia by altering forest microclimate and fuel dynamics. To isolate the effects of fuel loads on fire behavior and fire-induced changes in forest carbon cycling, we manipulated fine fuel loads in a fire experiment located in southeast Amazonia. We predicted that a 50% increase in fine fuel loads would disproportionally increase fire intensity and severity (i.e., tree mortality and losses in carbon stocks) due to multiplicative effects of fine fuel loads on the rate of fire spread, fuel consumption, and burned area. The experiment followed a fully replicated randomized block design (N = 6) comprised of unburned control plots and burned plots that were treated with and without fine fuel additions. The fuel addition treatment significantly increased burned area (+22%) and consequently canopy openness (+10%), fine fuel combustion (+5%), and mortality of individuals ≥5 cm in diameter at breast height (dbh; +37%). Surprisingly, we observed nonsignificant effects of the fuel addition treatment on fireline intensity, and no significant differences among the three treatments for (i) mortality of large trees (≥30 cm dbh), (ii) aboveground forest carbon stocks, and (iii) soil respiration. It was also surprising that postfire tree growth and wood increment were higher in the burned plots treated with fuels than in the unburned control. These results suggest that (i) fine fuel load accumulation increases the likelihood of larger understory fires and (ii) single, low-intensity fires weakly influence carbon cycling of this primary neotropical forest, although delayed postfire mortality of large trees may lower carbon stocks over the long term. Overall, our findings indicate that increased fine fuel loads alone are unlikely to create threshold conditions for high-intensity, catastrophic fires during nondrought years. © 2016 John Wiley & Sons Ltd.

  12. The ICIF project: Assessment of pathways of innovative cultures in forest for biomass production. Final report on the implementation of the experimental arrangement in Ardennes

    International Nuclear Information System (INIS)

    Rantien, Caroline; Gibaud, Gwenaelle; Richter, Claudine; Pousse, Noemie; Boulanger, Vincent; Deleuze, Christine

    2014-12-01

    Within the context created by the objective to increase the production of biomass-based energy, the authors studied the possibilities of using various crops and species in forests (i.e. in more acid soils), but also the impacts of these cultures on soil fertility. In a first part, they present and describe the experimental installation: site selection and characterization, experiment scheme, ash supply (choice, packaging, origin of ashes), and realisation. Then, they report the study of plants growth after one year, report some measurements regarding initial soil conditions (physical and chemical properties), and observations about flora development. They also mention performed information and communication action, and discuss perspectives

  13. The Black Rock Forest Consortium: A narrative

    Science.gov (United States)

    Buzzetto-More, Nicole Antoinette

    The Black Rock Forest is a 3,785-acre wilderness area whose richly forested landscape represents the splendor of the Hudson Valley Region of New York State. Although originally intended to become the home of wealthy banker James Stillman, it was his son Ernest whose love of conservation caused him to embrace the then new and revolutionary practice of sustainable forestry and establish Black Rock in 1928. Due to Ernest Stillman's foresight, the property was protected from development and bequeathed to Harvard University following his death for the establishment of an experimental forest. The modern environmental movement in America began when the Black Rock Forest was threatened with development by Consolidated Edison, and the people of the surrounding community banded together, battling tirelessly for over 17 years to stop the degradation of this historic forest. The outcome of this crusade marked a hallmark win for the environment leaving an illustrious and inveterate legacy. The campaign resulted in the watershed legislation the National Environmental Policy Act, the formation of several environmental advocacy groups, the creation of the Council on Environmental Quality of the Executive Office of the President, as well as set a precedent for communities to initiate and win cases against major corporations in order to safeguard natural resources. In the midst of the controversy it became apparent that alternative futures for the Forest needed to be explored. As a result of a committee report and one man's vision, the idea emerged to create a consortium that would purchase and steward the Forest. With a formation that took nearly fifteen years, the Black Rock Forest Consortium was formed, a unique amalgamation of K--12 public and private schools, colleges and universities, and science and cultural centers that successfully collaborate to enhance scientific research, environmental conservation, and education. The Consortium works to bridge the gaps between learners

  14. Experimental study on water transport observations of desert riparian forests in the lower reaches of the Tarim River in China.

    Science.gov (United States)

    Chen, Yaning; Li, Weihong; Zhou, Honghua; Chen, Yapeng; XinmingHao; Fu, Aihong; Ma, Jianxin

    2017-06-01

    Studying the water use processes of desert riparian vegetation in arid regions and analyzing the response and adaptation strategies of plants to drought stress are of great significance for developing ecological restoration measures. Based on field monitoring and test analyses of physiological ecological indicators of dominant species (Populus euphratica and Tamarix chinensis) in the desert riparian forest in the lower reaches of the Tarim River, the water relations of P. euphratica and T. chinensis under drought stress are discussed and some water use strategies put forward. The results show that (1) concerning plant water uptake, desert riparian forests depend mainly on groundwater to survive under long-term water stress. (2) Concerning plant water distribution, the survival of P. euphratica and nearby shallow root plants is mainly due to the hydraulic lift and water redistribution of P. euphratica under drought stress. (3) Concerning plant water transport, P. euphratica sustains the survival of competitive and advantageous branches by improving their ability to acquire water while restraining the growth of inferior branches. (4) Concerning plant transpiration, the sap flow curves of daily variations of P. euphratica and T. chinensis were wide-peak sin and narrower-peak respectively. T. chinensis has better environmental adaptability.

  15. Breathing Valley Fever

    Centers for Disease Control (CDC) Podcasts

    2014-02-04

    Dr. Duc Vugia, chief of the Infectious Diseases Branch in the California Department of Public Health, discusses Valley Fever.  Created: 2/4/2014 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 2/5/2014.

  16. Hidden Valley Search at ATLAS

    CERN Document Server

    Verducci, M

    2011-01-01

    A number of extensions of the Standard Model result in neutral and weakly-coupled particles that decay to multi hadrons or multi leptons with macroscopic decay lengths. These particles with decay paths that can be comparable with ATLAS detector dimensions represent, from an experimental point of view, a challenge both for the trigger and for the reconstruction capabilities of the ATLAS detector. We will present a set of signature driven triggers for the ATLAS detector that target such displaced decays and evaluate their performances for some benchmark models and describe analysis strategies and limits on the production of such long-lived particles. A first estimation of the Hidden Valley trigger rates has been evaluated with 6 pb-1 of data collected at ATLAS during the data taking of 2010.

  17. Interactions and competition processes among tree species in young experimental mixed forests, assessed with chlorophyll fluorescence and leaf morphology.

    Science.gov (United States)

    Pollastrini, M; Holland, V; Brüggemann, W; Koricheva, J; Jussila, I; Scherer-Lorenzen, M; Berger, S; Bussotti, F

    2014-03-01

    Chlorophyll a fluorescence (ChlF) and leaf morphology were assessed in two sites in Europe (Kaltenborn, Germany, and Satakunta, Finland) within a forest diversity experiment. Trees at Satakunta, planted in 1999, form a stratified canopy, while in Kaltenborn the trees are 7 years old, with no apparent canopy connection among broadleaf species. The following ChlF parameters from measured OJIP transient curves were examined: F(V)/F(M) (a proxy for maximum quantum yield); ΨEo (a proxy for efficiency in transferring an electron from reduced QA to the electron transport chain); I-P phase (a proxy for efficiency of reducing final acceptors beyond PSI); and PItot (total performance index for potential energy conservation from photons absorbed by PSII to reduction of PSI end acceptors). At Satakunta F(V)/F(M) and ΨEo in Betula pendula were higher in monocultures and lower in mixed plots, perhaps due to increasing light availability in mixed plots, which can induce photoinhibition. The opposite trend was observed in Picea abies, which was shaded in mixed plots. At Kaltenborn F(V)/F(M) decreased in Fagus sylvatica and P. abies in mixed plots due to competition both above- and belowground. At Satakunta LMA increased in B. pendula leaves with increasing species richness. Leaf area of ten leaves was reduced in F. sylvatica in mixed plots at Kaltenborn. By up-scaling the overall fluorescence response to plot level (PItot_plot ), a significant positive correlation with tree diversity was found at Kaltenborn, but not at Satakunta. This could suggest that competition/facilitation processes in mixed stands play a significant role in the early stages of forest establishment, but then tend to be compensated in more mature stands. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.

  18. Establishing Mixtures of Redcedar In Poor Oak-Hickory Forests

    Science.gov (United States)

    Leon S. Minckler

    1966-01-01

    Oak-history forests on the poorest sites in the Upper Mississippi Valley have both low productivity and little esthetic appeal. A mixture of the native evergreen redcedar would add bearty and increase wildlife values.

  19. Superior Valley Polarization and Coherence of 2s Excitons in Monolayer WSe_{2}.

    Science.gov (United States)

    Chen, Shao-Yu; Goldstein, Thomas; Tong, Jiayue; Taniguchi, Takashi; Watanabe, Kenji; Yan, Jun

    2018-01-26

    We report the experimental observation of 2s exciton radiative emission from monolayer tungsten diselenide, enabled by hexagonal boron nitride protected high-quality samples. The 2s luminescence is highly robust and persists up to 150 K, offering a new quantum entity for manipulating the valley degree of freedom. Remarkably, the 2s exciton displays superior valley polarization and coherence than 1s under similar experimental conditions. This observation provides evidence that the Coulomb-exchange-interaction-driven valley-depolarization process, the Maialle-Silva-Sham mechanism, plays an important role in valley excitons of monolayer transition metal dichalcogenides.

  20. Superior Valley Polarization and Coherence of 2 s Excitons in Monolayer WSe2

    Science.gov (United States)

    Chen, Shao-Yu; Goldstein, Thomas; Tong, Jiayue; Taniguchi, Takashi; Watanabe, Kenji; Yan, Jun

    2018-01-01

    We report the experimental observation of 2 s exciton radiative emission from monolayer tungsten diselenide, enabled by hexagonal boron nitride protected high-quality samples. The 2 s luminescence is highly robust and persists up to 150 K, offering a new quantum entity for manipulating the valley degree of freedom. Remarkably, the 2 s exciton displays superior valley polarization and coherence than 1 s under similar experimental conditions. This observation provides evidence that the Coulomb-exchange-interaction-driven valley-depolarization process, the Maialle-Silva-Sham mechanism, plays an important role in valley excitons of monolayer transition metal dichalcogenides.

  1. Discharge and sediment loads at the Kings River Experimental Forest in the Southern Sierra Nevada of California

    Science.gov (United States)

    S.M. Eagan; C.T. Hunsaker; C.R. Dolanc; M.E. Lynch; C.R. Johnson

    2007-01-01

    The Kings River Experimental Watershed (KREW) is now in its third year of data collection on eight small perennial watersheds. We are collecting meteorology, stream discharge, sediment load, water chemistry, shallow soil water chemistry, vegetation, macro-invertebrate, stream microclimate, and air quality data. This paper primarily examines discharge and sediment data...

  2. Modification of Soil Solid Aluminium Phases During an Extreme Experimental Acidification of A Horizons of Forest Soils from Southwest Europe

    International Nuclear Information System (INIS)

    Novoa-Munoz, J. C.; Garcia-Rodeja Gayoso, E.

    2007-01-01

    Four umbric A horizons from acid forest soils were acidified in a batch type experiment and its effect in the Al pools of the solid phase analysed by means of selective dissolution methods. The results showed that Al release accounted for the consumption of 85-99% of the added protons, and causes a decrease of 2-33% of the 'reactive' Al pool of the soil solid phase. In these A horizons, inorganic non-crystalline Al and high stability Al-humus complexes are the main sources of the dissolved Al. The contribution of the complexes with intermediate stability only was relevant in the more acid horizon developed from phyllites (P18-A). The increase of equilibration time from 96 to 720 h did not caused significant differences in the decrease of the 'reactive' Al pool suggesting the acid neutralising reactions occurred in less than 96 h. In most cases the quantity of released Al is in agreement with the decrease of the different reactive Al pools of the solid phase

  3. Input-Output Budget of Nitrogen and the Effect of Experimentally Changed Deposition in the Forest Ecosystems in Central Japan

    Directory of Open Access Journals (Sweden)

    Junko Shindo

    2001-01-01

    Full Text Available To evaluate the current nitrogen (N status in Japanese forests, field measurements of rainfall, throughfall, litter layer percolation, and soil solution percolation were conducted in a red pine stand (Kannondai and a deciduous stand (Yasato located in central Japan. N input via throughfall was 31 and 14 kg ha–1 year–1and output below rooting zone was 9.6 and 5.5 kg ha1 year–1 in Kannondai and in Yasato, respectively. Two thirds of input N were retained in plant-soil systems. Manipulation of N input was carried out. Ionic constituents were removed from throughfall with ion exchange resin at removal sites and ammonium nitrate containing twice the N of the throughfall was applied at N addition sites periodically. SO42– output below 20-cm soil layer changed depending on the input, while NO3– output was regulated mainly by the internal cycle and effect of manipulation was undetected. These Japanese stands were generally considered to have a larger capacity to assimilate N than NITREX sites in Europe. However, N output fluxes had large spatial variability and some sites in Kannondai showed high N leaching below rooting zone almost balanced with the input via throughfall.

  4. A Real Options Method for Estimating the Adoption Potential of Forestry and Agroforestry Systems on Private Lands in the Lower Mississippi Alluvial Valley, USA

    Science.gov (United States)

    Gregory E. Frey; D. Evan Mercer; Frederick W. Cubbage; Robert C. Abt

    2010-01-01

    The Lower Mississippi River Alluvial Valley (LMAV), once was the largest forested bottom-land area in the continental United States, but has undergone widespread loss of forest through conversion to farmland. Restoration of forest functions and values has been a key conservation goal in the LMAV since the 1970s. This study utilizes a partial differential real options...

  5. Composição e configuração da paisagem da sub-bacia do arroio jacaré, Vale do Taquari, RS, com ênfase nas áreas de florestas Landscape composition and configuration of jacaré stream sub-basin, Taquari Valley, RS, with emphasis on the forest areas

    Directory of Open Access Journals (Sweden)

    Gisele Cemin

    2009-08-01

    Full Text Available A conversão de áreas com cobertura florestal contínua por fragmentos florestais vem contribuindo para a diminuição da diversidade biológica, em função da perda de micro-habitats únicos, mudanças nos padrões de dispersão e migração, isolamento de habitats e erosão do solo. A solução desses problemas está intimamente vinculada ao planejamento e manutenção de bacias hidrográficas. A sub-bacia do Arroio Jacaré, localizada no Vale do Taquari, RS, compreende uma área de 538,98 km², onde estão parcial ou totalmente inseridos nove municípios. Essa bacia se encontra em uma região de ecótono entre as formações vegetais do tipo Floresta Estacional Decidual (FED e Floresta Ombrófila Mista - Mata de Araucária (FOM. Foram elaboradas e analisadas informações relacionadas às características estruturais das classes de mata na região (FED, FOM e vegetação secundária, utilizando-se imagem do satélite Landsat 7 ETM+, referente à passagem 04/02/2002 e software de Sistemas de Informações Geográficas (SIG Idrisi, 3.2, software de Ecologia de Paisagem Fragstats 3.3. Os resultados indicaram que a região apresenta aproximadamente 50% de suas matas nativas conservadas ou em estágio de regeneração, porém de forma altamente fragmentada, com 87,82% dos fragmentos menores que 1 ha. Considerando um efeito de borda de 50 m, em torno de 40% dos fragmentos ainda apresentam área nuclear.The conversion of continuous forest coverage areas into forest fragments has contributed to the decrease of the biological diversity due to the micro-habitat loss, changes in dispersion and migration patterns, habitats' isolation and soil erosion. The solution for those problems is intimately linked to the planning and maintenance of hydrographic basins. Jacaré's stream sub-basin is located in Taquari Valley, RS, with an area of 538,98 km², where nine municipal districts are partially or totally inserted. This basin is in an ecotone area among

  6. Deriving habitat models for northern long-eared bats from historical detection data: A case study using the Fernow Experimental Forest

    Science.gov (United States)

    Ford, W. Mark; Silvis, Alexander; Rodrigue, Jane L.; Kniowski, Andrew B.; Johnson, Joshua B.

    2016-01-01

    The listing of the northern long-eared bat (Myotis septentrionalis) as federally threatened under the Endangered Species Act following severe population declines from white-nose syndrome presents considerable challenges to natural resource managers. Because the northern long-eared bat is a forest habitat generalist, development of effective conservation measures will depend on appropriate understanding of its habitat relationships at individual locations. However, severely reduced population sizes make gathering data for such models difficult. As a result, historical data may be essential in development of habitat models. To date, there has been little evaluation of how effective historical bat presence data, such as data derived from mist-net captures, acoustic detection, and day-roost locations, may be in developing habitat models, nor is it clear how models created using different data sources may differ. We explored this issue by creating presence probability models for the northern long-eared bat on the Fernow Experimental Forest in the central Appalachian Mountains of West Virginia using a historical, presence-only data set. Each presence data type produced outputs that were dissimilar but that still corresponded with known traits of the northern long-eared bat or are easily explained in the context of the particular data collection protocol. However, our results also highlight potential limitations of individual data types. For example, models from mist-net capture data only showed high probability of presence along the dendritic network of riparian areas, an obvious artifact of sampling methodology. Development of ecological niche and presence models for northern long-eared bat populations could be highly valuable for resource managers going forward with this species. We caution, however, that efforts to create such models should consider the substantial limitations of models derived from historical data, and address model assumptions.

  7. The combined effects of a long-term experimental drought and an extreme drought on the use of plant-water sources in a Mediterranean forest.

    Science.gov (United States)

    Barbeta, Adrià; Mejía-Chang, Monica; Ogaya, Romà; Voltas, Jordi; Dawson, Todd E; Peñuelas, Josep

    2015-03-01

    Vegetation in water-limited ecosystems relies strongly on access to deep water reserves to withstand dry periods. Most of these ecosystems have shallow soils over deep groundwater reserves. Understanding the functioning and functional plasticity of species-specific root systems and the patterns of or differences in the use of water sources under more frequent or intense droughts is therefore necessary to properly predict the responses of seasonally dry ecosystems to future climate. We used stable isotopes to investigate the seasonal patterns of water uptake by a sclerophyll forest on sloped terrain with shallow soils. We assessed the effect of a long-term experimental drought (12 years) and the added impact of an extreme natural drought that produced widespread tree mortality and crown defoliation. The dominant species, Quercus ilex, Arbutus unedo and Phillyrea latifolia, all have dimorphic root systems enabling them to access different water sources in space and time. The plants extracted water mainly from the soil in the cold and wet seasons but increased their use of groundwater during the summer drought. Interestingly, the plants subjected to the long-term experimental drought shifted water uptake toward deeper (10-35 cm) soil layers during the wet season and reduced groundwater uptake in summer, indicating plasticity in the functional distribution of fine roots that dampened the effect of our experimental drought over the long term. An extreme drought in 2011, however, further reduced the contribution of deep soil layers and groundwater to transpiration, which resulted in greater crown defoliation in the drought-affected plants. This study suggests that extreme droughts aggravate moderate but persistent drier conditions (simulated by our manipulation) and may lead to the depletion of water from groundwater reservoirs and weathered bedrock, threatening the preservation of these Mediterranean ecosystems in their current structures and compositions. © 2014

  8. 77 FR 33237 - Saline Valley Warm Springs Management Plan/Environmental Impact Statement, Death Valley National...

    Science.gov (United States)

    2012-06-05

    ... Valley Warm Springs Management Plan/Environmental Impact Statement, Death Valley National Park, Inyo... an Environmental Impact Statement for the Saline Valley Warm Springs Management Plan, Death Valley... analysis process for the Saline Valley Warm Springs Management Plan for Death Valley [[Page 33238...

  9. Valley Topological Phases in Bilayer Sonic Crystals

    Science.gov (United States)

    Lu, Jiuyang; Qiu, Chunyin; Deng, Weiyin; Huang, Xueqin; Li, Feng; Zhang, Fan; Chen, Shuqi; Liu, Zhengyou

    2018-03-01

    Recently, the topological physics in artificial crystals for classical waves has become an emerging research area. In this Letter, we propose a unique bilayer design of sonic crystals that are constructed by two layers of coupled hexagonal array of triangular scatterers. Assisted by the additional layer degree of freedom, a rich topological phase diagram is achieved by simply rotating scatterers in both layers. Under a unified theoretical framework, two kinds of valley-projected topological acoustic insulators are distinguished analytically, i.e., the layer-mixed and layer-polarized topological valley Hall phases, respectively. The theory is evidently confirmed by our numerical and experimental observations of the nontrivial edge states that propagate along the interfaces separating different topological phases. Various applications such as sound communications in integrated devices can be anticipated by the intriguing acoustic edge states enriched by the layer information.

  10. The California Valley grassland

    Science.gov (United States)

    Keeley, J.E.; Schoenherr, Allan A.

    1990-01-01

    Grasslands are distributed throughout California from Oregon to Baja California Norte and from the coast to the desert (Brown 1982) (Figure 1). This review will focus on the dominant formation in cismontane California, a community referred to as Valley Grassland (Munz 1959). Today, Valley Grassland is dominated by non-native annual grasses in genera such as Avena (wild oat), Bromus (brome grass), and Hordeum (barley), and is often referred to as the California annual grassland. On localized sites, native perennial bunchgrasses such as Stipa pultra (purple needle grass) may dominate and such sites are interpreted to be remnants of the pristine valley grassland. In northwestern California a floristically distinct formation of the Valley Grassland, known as Coast Prairie (Munz 1959) or Northern Coastal Grassland (Holland and Keil 1989) is recognized. The dominant grasses include many native perennial bunchgrasses in genera such as Agrostis, Calamagrostis, Danthonia, Deschampsia, Festuca, Koeleria and Poa (Heady et al. 1977). Non-native annuals do not dominate, but on some sites non-native perennials like Anthoxanthum odoratum may colonize the native grassland (Foin and Hektner 1986). Elevationally, California's grasslands extend from sea level to at leas 1500 m. The upper boundary is vague because montane grassland formations are commonly referred to as meadows; a community which Munz (1959) does not recognize. Holland and Keil (1989) describe the montane meadow as an azonal community; that is, a community restricted not so much to a particular climatic zone but rather controlled by substrate characteristics. They consider poor soil-drainage an over-riding factor in the development of montane meadows and, in contrast to grasslands, meadows often remain green through the summer drought. Floristically, meadows are composed of graminoids; Cyperaceae, Juncaceae, and rhizomatous grasses such as Agropyron (wheat grass). Some bunchgrasses, such as Muhlenbergia rigens, are

  11. Rift Valley Fever.

    Science.gov (United States)

    Hartman, Amy

    2017-06-01

    Rift Valley fever (RVF) is a severe veterinary disease of livestock that also causes moderate to severe illness in people. The life cycle of RVF is complex and involves mosquitoes, livestock, people, and the environment. RVF virus is transmitted from either mosquitoes or farm animals to humans, but is generally not transmitted from person to person. People can develop different diseases after infection, including febrile illness, ocular disease, hemorrhagic fever, or encephalitis. There is a significant risk for emergence of RVF into new locations, which would affect human health and livestock industries. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Aburra Valley: Quo vadis?

    International Nuclear Information System (INIS)

    Hermelin, Michel

    2008-01-01

    These paper intents a brief description of the evolution that characterised natural risk prevention in the area surrounding the city of Medellin, Colombia, called the Aburra Valley. Both the lithological and structural composition of the Valle and its topographic and climatic conditions contribute to the abundance of destructive natural phenomena as earthquakes, slope movements, flash floods and, in a lower proportion, to floods. The population increase, which reaches now 3.5 millions inhabitants and the frequent occupation of sites exposed to natural hazards have resulted in numerous disasters. At present two entities called SIMPAD and DAPARD work on risk prevention, on city and department scale respectively. The amount of knowledge about physical environment is considered to be insufficient, together with regulations which should direct land use in accordance to restrictions related to natural hazards. Several seminars on this topic have already been carried out and the organisers of the present one, destined to commemorate the twentieth anniversary of the Villatina disaster, should make the decision to meet each two years. Furthermore, the creation of a permanent commission dedicated to study past events, to foster information broadcasting and to seek a better knowledge of the Aburra Valley, should be considered

  13. Seasonality and structure of the arthropod community in a forested ...

    African Journals Online (AJOL)

    The structure of an arthropod community in the forest floor vegetation was studied in a low altitude (about 700 m a.s.l.) forest valley in the Uluguru Mountains near Morogoro, Tanzania, by monthly sweep net sampling during one year (December 1996-November 1997). The community structure of arthropods changed ...

  14. Forest management practices and silviculture. Chapter 12.

    Science.gov (United States)

    Donald A. Perala; Elon S. Verry

    2011-01-01

    This chapter is an overview of forest management and silviculture practices, and lessons learned, on the Marcell Experimental Forest (MEF). The forests there are a mosaic of natural regeneration and conifer plantations. Verry (1969) described forest-plant communities in detail for the study watersheds (Sl through S6) on the MEF. The remaining area is described in...

  15. Global Positioning System (GPS) and Geographic Information System (GIS) analysis of mobile harvesting equipment and sediment delivery to streams during forest harvest operations on steep terrain: Experimental design

    Science.gov (United States)

    Daniel Bowker; Jeff Stringer; Chris Barton; Songlin Fei

    2011-01-01

    Sediment mobilized by forest harvest machine traffic contributes substantially to the degradation of headwater stream systems. This study monitored forest harvest machine traffic to analyze how it affects sediment delivery to stream channels. Harvest machines were outfitted with global positioning system (GPS) dataloggers, recording machine movements and working status...

  16. Evaluating the role of cutting treatments, fire and soil seed banks in an experimental framework in ponderosa pine forests of the Black Hills, South Dakota

    Science.gov (United States)

    Cody L. Wienk; Carolyn Hull Sieg; Guy R. McPherson

    2004-01-01

    Pinus ponderosa Laws. (ponderosa pine) forests have changed considerably during the past century, partly because recurrent fires have been absent for a century or more. A number of studies have explored the influence of timber harvest or burning on understory production in ponderosa pine forests, but study designs incorporating cutting and prescribed...

  17. Urban Forests

    Science.gov (United States)

    David Nowak

    2016-01-01

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

  18. Valley development on Hawaiian volcanoes

    International Nuclear Information System (INIS)

    Baker, V.R.; Gulick, V.C.

    1987-01-01

    Work in progress on Hawaiian drainage evolution indicates an important potential for understanding drainage development on Mars. Similar to Mars, the Hawaiian valleys were initiated by surface runoff, subsequently enlarged by groundwater sapping, and eventually stabilized as aquifers were depleted. Quantitative geomorphic measurements were used to evaluate the following factors in Hawaiian drainage evolution: climate, stream processes, and time. In comparing regions of similar climate, drainage density shows a general increase with the age of the volcani island. With age and climate held constant, sapping dominated valleys, in contrast to runoff-dominated valleys, display the following: lower drainage densities, higher ratios of valley floor width to valley height, and more positive profile concavities. Studies of stream junction angles indicate increasing junction angles with time on the drier leeward sides of the major islands. The quantitative geomorphic studies and earlier field work yielded important insights for Martian geomorphology. The importance of ash mantling in controlling infiltration on Hawaii also seems to apply to Mars. The Hawaiian valley also have implications for the valley networks of Martian heavily cratered terrains

  19. Geohydrology of the Unconsolidated Valley-Fill Aquifer in the Meads Creek Valley, Schuyler and Steuben Counties, New York

    Science.gov (United States)

    Miller, Todd S.; Bugliosi, Edward F.; Reddy, James E.

    2008-01-01

    The Meads Creek valley encompasses 70 square miles of predominantly forested uplands in the upper Susquehanna River drainage basin. The valley, which was listed as a Priority Waterbody by the New York State Department of Environmental Conservation in 2004, is prone to periodic flooding, mostly in its downstream end, where development is occurring most rapidly. Hydraulic characteristics of the unconsolidated valley-fill aquifer were evaluated, and seepage rates in losing and gaining tributaries were calculated or estimated, in an effort to delineate the aquifer geometry and identify the factors that contribute to flooding. Results indicated that (1) Meads Creek gained about 61 cubic feet of flow per second (about 6.0 cubic feet per second per mile of stream channel) from ground-water discharge and inflow from tributaries in its 10.2-mile reach between the northernmost and southernmost measurement sites; (2) major tributaries in the northern part of the valley are not significant sources of recharge to the aquifer; and (3) major tributaries in the central and southern part of the valley provide recharge to the aquifer. The ground-water portion of streamflow in Meads Creek (excluding tributary inflow) was 11.3 cubic feet per second (ft3/s) in the central part of the valley and 17.2 ft3/s in the southern part - a total of 28.5 ft3/s. Ground-water levels were measured in 29 wells finished in unconfined deposits for construction of a potentiometric-surface map to depict directions of ground-water flow within the valley. In general, ground water flows from the edges of the valley toward Meads Creek and ultimately discharges to it. The horizontal hydraulic gradient for the entire 12-mile-long aquifer averages about 30 feet per mile, whereas the gradient in the southern fourth of the valley averages about half that - about 17 feet per mile. A water budget for the aquifer indicated that 28 percent of recharge was derived from precipitation that falls on the aquifer, 32

  20. Forest rights

    DEFF Research Database (Denmark)

    Balooni, Kulbhushan; Lund, Jens Friis

    2014-01-01

    One of the proposed strategies for implementation of reducing emissions from deforestation and forest degradation plus (REDD+) is to incentivize conservation of forests managed by communities under decentralized forest management. Yet, we argue that this is a challenging road to REDD+ because...... conservation of forests under existing decentralized management arrangements toward a push for extending the coverage of forests under decentralized management, making forest rights the hard currency of REDD+....

  1. The Drentsche Aa valley system

    International Nuclear Information System (INIS)

    Gans, W. de.

    1981-01-01

    This thesis is composed of five papers concerned with Late Quaternary geology and geomorphology of the Aa valley system. The correlation and chronostratigraphic position of the layers have been established by radiocarbon dating. (Auth.)

  2. Experimental soil warming effects on CO2 and CH4 flux from a low elevation spruce-fir forest soil in Maine, USA

    Science.gov (United States)

    Lindsey E. Rustad; Ivan J. Fernandez

    1998-01-01

    The effect of soil warming on CO2 and CH4 flux from a spruce-fir forest soil was evaluated at the Howland Integrated Forest Study site in Maine, USA from 1993 to 1995. Elevated soil temperatures (~5 °C) were maintained during the snow-free season (May-November) in replicated 15 × 15-m plots using electric cables buried 1-2...

  3. Draft environmental impact statement - BPA/Lower Valley transmission project

    International Nuclear Information System (INIS)

    1997-06-01

    Bonneville Power Administration and Lower Valley Power and Light, Inc., propose to solve a voltage stability problem in the Jackson and Afton, Wyoming areas. For the Agency Proposed Action, BPA and Lower Valley would construct a new 115-kV line from BPA's Swan Valley Substation near Swan Valley in Bonneville County, Idaho about 58 km (36 miles) east to BPA's Teton Substation near Jackson in Teton County, Wyoming. The new line would be next to an existing 115-kV line. Most of the line would be supported by a mix of single-circuit wood pole H-frame structures would be used. The Single-Circuit Line Alternative has all the components of the Agency Proposed Action except that the entire line would be supported by single-circuit structures. The Short Line Alternative has all the components of the Single-Circuit Line Alternative except it would then be removed. For the Static Var Compensation Alternative, BPA would install a Static Var Compensator (SVC) at Teton or Jackson Substation. An SVC is a group of electrical equipment placed at a substation to help control voltage on a transmission system. The No Action Alternative assumes that no new transmission line is built, and no other equipment is added to the transmission system. The USFS (Targhee and Bridger-Teton National Forests) must select al alternative based on their needs and objectives, decide if the project complies with currently approved forest plans, decide if special use permits or easements are needed for construction, operation, and maintenance of project facilities, and decide if they would issue special use permits and letters of consent to grant easements for the project

  4. Viewing Forests Through a Historical Lens

    Science.gov (United States)

    Noreen Parks; Eric [< em> featured scientist< /em> ]. Knapp

    2009-01-01

    Past records on fire-resilient, biodiverse stands could offer models for the future.  This year marks the centennial of the Forest Service’s nationwide network of 80 experimental forests and ranges, which serve as field laboratories for long-term studies on the science and management of national forests. At the Stanislaus-Tuolumne Experimental Forest in the central...

  5. Birds of the St. Croix River valley: Minnesota and Wisconsin

    Science.gov (United States)

    Faanes, Craig A.

    1981-01-01

    The St. Croix River Valley encompasses nearly 11,550 km2 in east-central Minnesota and northwestern Wisconsin. A wide range of habitats are available for birds including upland oak, lowland deciduous, maple-basswood, lowland and upland coniferous forests, natural basin wetlands, and grasslands. Situated in the north-central region of the United States, the valley is a biological 'crossroads' for many species. Because of the mixed affinities of plant communities, the valley includes the northern and southern range limits for a number of species. Also, because the valley lies near the forest-prairie transition zone, many typical western breeding species (e.g. pintail, western meadowlark, yellow-headed blackbird) breed in proximity to typical eastern species such as tufted titmouse, eastern meadowlark, and cardinal. From 1966 to 1980, I conducted extensive surveys of avian distribution and abundance in the St. Croix River Valley. I have supplemented the results of these surveys with published and unpublished observations contributed by many ornithologists. These additional data include compilations from Christmas Bird Counts sponsored by the National Audubon Society and from the Breeding Bird Survey coordinated by the U.S. Fish and Wildlife Service. Three hundred fourteen species have been recorded in the study area; data are presented on the migration period, nesting season distribution, winter distribution, relative abundance, and habitat use of each species. Recognizing the uniqueness of the area, and its importance not only to wildlife but also to man, the U.S. Congress designated the St. Croix a National Scenic Riverway. This action provided a considerable degree of protection to lands along and directly adjacent to the river. Unfortunately, no similar legal measure exists to protect lands away from the river. With the exception of the northern quarter of the St. Croix River Valley, agricultural interests have made significant inroads into the habitat base. The

  6. Forest soils

    Science.gov (United States)

    Charles H. (Hobie) Perry; Michael C. Amacher

    2009-01-01

    Productive soils are the foundation of sustainable forests throughout the United States. Forest soils are generally subjected to fewer disturbances than agricultural soils, particularly those that are tilled, so forest soils tend to have better preserved A-horizons than agricultural soils. Another major contrast between forest and agricultural soils is the addition of...

  7. Forest hydrology

    Science.gov (United States)

    Ge Sun; Devendra Amatya; Steve McNulty

    2016-01-01

    Forest hydrology studies the distribution, storage, movement, and quality of water and the hydrological processes in forest-dominated ecosystems. Forest hydrological science is regarded as the foundation of modern integrated water¬shed management. This chapter provides an overview of the history of forest hydrology and basic principles of this unique branch of...

  8. Forest Management

    Science.gov (United States)

    S. Hummel; K. L. O' Hara

    2008-01-01

    Global variation in forests and in human cultures means that a single method for managing forests is not possible. However, forest management everywhere shares some common principles because it is rooted in physical and biological sciences like chemistry and genetics. Ecological forest management is an approach that combines an understanding of universal processes with...

  9. Microbial community stratification linked to utilization of carbohydrates and phosphorus limitation in a boreal peatland at Marcell Experimental Forest, Minnesota, USA.

    Science.gov (United States)

    Lin, Xueju; Tfaily, Malak M; Steinweg, J Megan; Chanton, Patrick; Esson, Kaitlin; Yang, Zamin K; Chanton, Jeffrey P; Cooper, William; Schadt, Christopher W; Kostka, Joel E

    2014-06-01

    This study investigated the abundance, distribution, and composition of microbial communities at the watershed scale in a boreal peatland within the Marcell Experimental Forest (MEF), Minnesota, USA. Through a close coupling of next-generation sequencing, biogeochemistry, and advanced analytical chemistry, a biogeochemical hot spot was revealed in the mesotelm (30- to 50-cm depth) as a pronounced shift in microbial community composition in parallel with elevated peat decomposition. The relative abundance of Acidobacteria and the Syntrophobacteraceae, including known hydrocarbon-utilizing genera, was positively correlated with carbohydrate and organic acid content, showing a maximum in the mesotelm. The abundance of Archaea (primarily crenarchaeal groups 1.1c and 1.3) increased with depth, reaching up to 60% of total small-subunit (SSU) rRNA gene sequences in the deep peat below the 75-cm depth. Stable isotope geochemistry and potential rates of methane production paralleled vertical changes in methanogen community composition to indicate a predominance of acetoclastic methanogenesis mediated by the Methanosarcinales in the mesotelm, while hydrogen-utilizing methanogens predominated in the deeper catotelm. RNA-derived pyrosequence libraries corroborated DNA sequence data to indicate that the above-mentioned microbial groups are metabolically active in the mid-depth zone. Fungi showed a maximum in rRNA gene abundance above the 30-cm depth, which comprised only an average of 0.1% of total bacterial and archaeal rRNA gene abundance, indicating prokaryotic dominance. Ratios of C to P enzyme activities approached 0.5 at the acrotelm and catotelm, indicating phosphorus limitation. In contrast, P limitation pressure appeared to be relieved in the mesotelm, likely due to P solubilization by microbial production of organic acids and C-P lyases. Based on path analysis and the modeling of community spatial turnover, we hypothesize that P limitation outweighs N limitation at

  10. Final Report, 2011-2014. Forecasting Carbon Storage as Eastern Forests Age. Joining Experimental and Modeling Approaches at the UMBS AmeriFlux Site

    Energy Technology Data Exchange (ETDEWEB)

    Curtis, Peter [The Ohio State Univ., Columbus, OH (United States); Bohrer, Gil [The Ohio State Univ., Columbus, OH (United States); Gough, Christopher [Virginia Commonwealth Univ., Richmond, VA (United States); Nadelhoffer, Knute [Univ. of Michigan, Ann Arbor, MI (United States)

    2015-03-12

    At the University of Michigan Biological Station (UMBS) AmeriFlux sites (US-UMB and US-UMd), long-term C cycling measurements and a novel ecosystem-scale experiment are revealing physical, biological, and ecological mechanisms driving long-term trajectories of C cycling, providing new data for improving modeling forecasts of C storage in eastern forests. Our findings provide support for previously untested hypotheses that stand-level structural and biological properties constrain long-term trajectories of C storage, and that remotely sensed canopy structural parameters can substantially improve model forecasts of forest C storage. Through the Forest Accelerated Succession ExperimenT (FASET), we are directly testing the hypothesis that forest C storage will increase due to increasing structural and biological complexity of the emerging tree communities. Support from this project, 2011-2014, enabled us to incorporate novel physical and ecological mechanisms into ecological, meteorological, and hydrological models to improve forecasts of future forest C storage in response to disturbance, succession, and current and long-term climate variation

  11. Electron spin resonance and spin-valley physics in a silicon double quantum dot.

    Science.gov (United States)

    Hao, Xiaojie; Ruskov, Rusko; Xiao, Ming; Tahan, Charles; Jiang, HongWen

    2014-05-14

    Silicon quantum dots are a leading approach for solid-state quantum bits. However, developing this technology is complicated by the multi-valley nature of silicon. Here we observe transport of individual electrons in a silicon CMOS-based double quantum dot under electron spin resonance. An anticrossing of the driven dot energy levels is observed when the Zeeman and valley splittings coincide. A detected anticrossing splitting of 60 MHz is interpreted as a direct measure of spin and valley mixing, facilitated by spin-orbit interaction in the presence of non-ideal interfaces. A lower bound of spin dephasing time of 63 ns is extracted. We also describe a possible experimental evidence of an unconventional spin-valley blockade, despite the assumption of non-ideal interfaces. This understanding of silicon spin-valley physics should enable better control and read-out techniques for the spin qubits in an all CMOS silicon approach.

  12. Diversity of inland valleys and opportunities for agricultural development in Sierra Leone.

    Directory of Open Access Journals (Sweden)

    Elliott Ronald Dossou-Yovo

    Full Text Available Inland valleys are becoming increasingly important agricultural production areas for rural households in sub-Saharan Africa due to their relative high and secure water availability and soil fertility. In addition, inland valleys are important as water buffer and biodiversity hot spots and they provide local communities with forest, forage, and fishing resources. As different inland-valley ecosystem functions may conflict with agricultural objectives, indiscriminate development should be avoided. This study aims to analyze the diversity of inland valleys in Sierra Leone and to develop guidelines for more precise interventions. Land use, biophysical and socio-economic data were analyzed on 257 inland valleys using spatial and multivariate techniques. Five cluster groups of inland valleys were identified: (i semi-permanently flooded with high soil organic carbon (4.2% and moderate available phosphorus (10.2 ppm, mostly under natural vegetation; (ii semi-permanently flooded with low soil organic carbon (1.5% and very low available phosphorus (3.1 ppm, abandoned by farmers; (iii seasonally flooded with moderate soil organic carbon (3.1% and low available phosphorus (8.3 ppm, used for rainfed rice and off-season vegetables produced without fertilizer application for household consumption and market; (iv well drained with moderate soil organic carbon (3.8% and moderate available phosphorus (10.0 ppm, used for rainfed rice and off-season vegetables produced with fertilizer application for household consumption and market; and (v well drained with moderate soil organic carbon (3.6% and moderate available phosphorus (11 ppm, used for household consumption without fertilizer application. Soil organic carbon, available phosphorus, hydrological regime, physical accessibility and market opportunity were the major factors affecting agricultural intensification of inland valleys. Opening up the areas in which inland valleys occur through improved roads and

  13. Plant diversity and conservation status of Himalayan Region Poonch Valley Azad Kashmir (Pakistan).

    Science.gov (United States)

    Khan, Muhammad Azam; Khan, Mir Ajab; Hussain, Mazhar; Mujtaba, Ghulam

    2014-09-01

    The plant diversity of Himalayan region has been reduced to greater extent due to environmental degradation and human exploitation. Anthropogenic disturbance was the major factor responsible for fragmentation of forest vegetation into small patches. Little research has been conducted in the Himalayan region of Poonch Valley of North eastern Pakistan with reference to plants biodiversity and its conservation. The present research was carried out to provide a checklist of vegetation for biodiversity conservation. A total of 430 vascular and 5 nonvascular plant species with 5 species of Bryophytes (5 families), 13 species of Pteridophytes (6 families), 4 species of Gymnosperms (1 family) and 413 species of angiosperms (95 families) were enumerated from the Poonch valley Azad Kashmir. The genera were classified into three categories according to the number of species. 25 plant communities with phytosociological parameters and diversity indices were reported. Present study revealed that there were 145 threatened, 30 endangered, 68 vulnerable and 47 rare species. It is recorded that extensive grazing, uprooting of plants and soil slope erosion intensify the environmental problems. Since there is maximum exploitation of vegetation, the valley showed a decline in plant diversity. The study was also indicated that the main threats to the biodiversity are expansion of settlement and army installations in the forest area of the valley. For sustainable use In-situ and Ex-situ conservation, controlled harvesting and afforestation may be the solution. Moreover, forest area should be declared prohibited for settlements and army installations.

  14. Forest understory plant and soil microbial response to an experimentally induced drought and heat-pulse event: the importance of maintaining the continuum

    Science.gov (United States)

    Isabell von Rein; Arthur Gessler; Katrin Premke; Claudia Keitel; Andreas Ulrich; Zachary E. Kayler

    2016-01-01

    Drought duration and intensity are expected to increase with global climate change. How changes in water availability and temperature affect the combined plant–soil–microorganism response remains uncertain. We excavated soil monoliths from a beech (Fagus sylvatica L.) forest, thus keeping the understory plant–microbe communities intact, imposed an...

  15. Experimental drought reduced acid and alkaline phosphatase activity and increased organic extractable P in soil in a Quercus ilex Mediterranean forest

    NARCIS (Netherlands)

    Sardans, J.; Penuelas, J.; Ogaya, R.

    2008-01-01

    A six-year (1999-2005) experiment of drought manipulation was conducted in a Quercus ilex Mediterranean forest (Southern Catalonia) to simulate predicted climatic conditions projected for the decades to come. The aim was to investigate the direct and indirect effects of drought conditions on acid

  16. Systematic Mapping and Statistical Analyses of Valley Landform and Vegetation Asymmetries Across Hydroclimatic Gradients

    Science.gov (United States)

    Poulos, M. J.; Pierce, J. L.; McNamara, J. P.; Flores, A. N.; Benner, S. G.

    2015-12-01

    Terrain aspect alters the spatial distribution of insolation across topography, driving eco-pedo-hydro-geomorphic feedbacks that can alter landform evolution and result in valley asymmetries for a suite of land surface characteristics (e.g. slope length and steepness, vegetation, soil properties, and drainage development). Asymmetric valleys serve as natural laboratories for studying how landscapes respond to climate perturbation. In the semi-arid montane granodioritic terrain of the Idaho batholith, Northern Rocky Mountains, USA, prior works indicate that reduced insolation on northern (pole-facing) aspects prolongs snow pack persistence, and is associated with thicker, finer-grained soils, that retain more water, prolong the growing season, support coniferous forest rather than sagebrush steppe ecosystems, stabilize slopes at steeper angles, and produce sparser drainage networks. We hypothesize that the primary drivers of valley asymmetry development are changes in the pedon-scale water-balance that coalesce to alter catchment-scale runoff and drainage development, and ultimately cause the divide between north and south-facing land surfaces to migrate northward. We explore this conceptual framework by coupling land surface analyses with statistical modeling to assess relationships and the relative importance of land surface characteristics. Throughout the Idaho batholith, we systematically mapped and tabulated various statistical measures of landforms, land cover, and hydroclimate within discrete valley segments (n=~10,000). We developed a random forest based statistical model to predict valley slope asymmetry based upon numerous measures (n>300) of landscape asymmetries. Preliminary results suggest that drainages are tightly coupled with hillslopes throughout the region, with drainage-network slope being one of the strongest predictors of land-surface-averaged slope asymmetry. When slope-related statistics are excluded, due to possible autocorrelation, valley

  17. Valley dynamics of intravalley and intervalley multiexcitonic states in monolayer WS2

    Science.gov (United States)

    Fu, Jiyong; Bezerra, Andre; Qu, Fanyao

    2018-03-01

    We present a comprehensive model comprising of a complete set of rate equations, which account for charge transfer among multiexcitonic channels including excitons, trions, and biexcitons, to investigate valley (locked with spin) dynamics in monolayer WS2. The steady-state photoluminescence (PL) spectra, underlying the laser power dependence of excitonic populations, are also determined. Our computed PL for all excitonic states agrees with the experimental data of Paradisanos et al. [Appl. Phys. Lett. 110, 193102 (2017), 10.1063/1.4983285]. We find that the relative weight of PL, stemmed from different excitonic channels, strongly depends on the laser power even under dynamical conditions. Remarkably, the biexciton channel, having the weakest PL intensity at low laser powers, tends to prevail in PL over other excitonic states as the power strengthens. In addition, by accounting for intervalley scatterings, which enable transfer of excitonic states from one valley to the other, we determine the valley polarization, which strongly depends on intervalley scatterings and the exciton generation rates in the two valleys. On the other hand, the valley polarization for all excitonic channels is found almost independent of the laser power, consistent with experimental measurements as well. Finally, the valley dynamics involving both intra- and intervalley trions is discussed. Our model and numerical outcome should be beneficial to experiments especially featuring the interplay of multiexcitonic channels in, e.g., elucidating experimental data, estimating central excitonic quantities including recombination times and transition rates, and in widening possible new experimental scopes.

  18. PHYTOCOENOSES OF URBAN RIPARIAN FORESTS ON THE EXAMPLE OF THE LAS OSOBOWICKI FOREST (WROCŁAW

    Directory of Open Access Journals (Sweden)

    Ewa Stefańska-Krzaczek

    2014-10-01

    Full Text Available The Las Osobowicki forest is remnant riparian woodland of the Odra valley. Floristic data were collected from circular 100m2 plots (with a radius of 5.64m which were systematically chosen in forest communities. Four plant communities were determined within data set. They were represented Fagetalia order and Querco-Fagetea class. Flood prevention caused disappearance of riparian forest species, expansion of common hornbeam and Norway maple expansion and a decrease of species richness. However, spatial distribution of phytocoenoses proves the river influence on the vegetation.

  19. Forest Resources

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-06-01

    Forest biomass is an abundant biomass feedstock that complements the conventional forest use of wood for paper and wood materials. It may be utilized for bioenergy production, such as heat and electricity, as well as for biofuels and a variety of bioproducts, such as industrial chemicals, textiles, and other renewable materials. The resources within the 2016 Billion-Ton Report include primary forest resources, which are taken directly from timberland-only forests, removed from the land, and taken to the roadside.

  20. Mineralogical effects of an experimental forest fire on a goethite/ferrihydrite soil - an attempt to solve the presence of hematite and maghemite in topsoils in a temperate region

    Science.gov (United States)

    Nørnberg, Per; Vendelboe, Anders L.; Gunnlaugsson, Haraldur P.; Merrison, Jonathan P.; Finster, Kai; Jensen, Svend K.

    2010-05-01

    Isolated soil spots, a few square metres in size, as red as Munsell colour 10R ¾ are found in Denmark. These spots are well known as places that have been exposed to fire. However, a long-standing unresolved puzzle is the presence of extended areas with high iron content (8-40 %) where goethite and ferrihydrite are present in the topsoil along with hematite and maghemite. Hematite and particularly maghemite would normally not be expected to occur under the temperate humid Danish climate, but be interpreted as the result of high temperature as found in tropical areas or after forest fires. However, a body of evidence argues against these sites having been exposed to fire. In an attempt to get closer to an explanation of this iron mineralogy, an experimental forest fire was produced. The results showed a clear mineralogical zonation down to 10 cm depth. This was not observed at the natural sites, which contained a uniform mixture of goethite/ferrihydrite, hematite and maghemite down to 20 cm depth. The experimental forest fire furthermore left charcoal and ashes at the topsoil, produced high pH and decreased organic matter content, all of which is in contrast to the natural sites. Physical and chemical date as well as XRD, Mössbauer spectroscopic data and TEM micrographs from the sites will be presented. The conclusion from this work is that the mineralogy of these sites is not consistent with exposure to fire, but may rather result from long term transformation within a reducing environment, possibly involving microorganisms. References: Nørnberg, P., Vendelboe, A.L., Gunnlaugsson, H.P., Merrison, J.P., Finster, K., Jensen, S.K. 2009 Mineralogy after an experimental forest fire on Quaternary soil goethite, compared with a hematite, maghemite, goethite containing topsoil. Clay Minerals, 44, 239-247. Nørnberg, P., Gunnlaugsson, H.P., Merrison, J.P., Vendelboe, A.L. 2009: Salten Skov I: A Martian dust analogue. Planetary and Space Science, 57, 628-631. Nørnberg, P

  1. Recovery from chronic and snowmelt acidification: Long-term trends in stream and soil water chemistry at the Hubbard Brook Experimental Forest, New Hampshire, USA

    Science.gov (United States)

    Colin B. Fuss; Charles T. Driscoll; John L. Campbell

    2015-01-01

    Atmospheric acid deposition of sulfate and nitrate has declined markedly in the northeastern United States due to emissions controls. We investigated long-term trends in soil water (1984–2011) and stream water (1982–2011) chemistry along an elevation gradient of a forested watershed to evaluate the progress of recovery of drainage waters from acidic deposition at the...

  2. Socioeconomic Collapse of Rural Areas, Atlantic Forest Transition and Sustainability

    Science.gov (United States)

    Silva, R. F. B. D.; Batistella, M.; Moran, E. F.

    2017-12-01

    Centuries of human pressure over the Atlantic Forest has led the biome to encompass only 11.7 percent of forest remnants. On the other hand, natural regeneration has explained forest cover increase in specific regions since the 1960s as an outcome of land use policies, environmental legislation, agricultural modernization, economic development, and landscape biophysical conditions. We analyze Forest Transition (FT) pathways for the Paraíba Valley region, São Paulo State, Brazil looking for more sustainable relationships between land use and natural land cover. During the 18th and 19th centuries, the Valley's farms were responsible for providing the largest portion of the state's wealth. Nowadays, the Valley contributes with only 6% to the state's gross product and the share of rural activities is now insignificant. Between 1962 and 2011, forest cover area increased from 225 to 446 thousand hectares. Rural household survey was conducted in three municipalities (n=90, thirty in each municipality). To select the municipalities among the thirty-four present in the Paraíba Valley, we applied the modified Thompson Tau technique to detect outlier values for three selected variables: natural forest cover, eucalyptus plantation cover, and municipal revenue. The outliers were discharged and the municipality with the best performance (maximum value) for each variable was selected. Based on the rural household surveys and GIS analysis of satellite imagery classifications, topography and hydrology variables, we conclude that the diminished land use pressure in the Paraíba Valley is allowing the regeneration of forest cover. Over the observed period, the FT was strongly influenced by the unsuitable topography for agriculture (steep slopes) and the economic urban development since the 1960s. However, more recently (2000s), FT is more affected by the vicinity of eucalyptus plantations, the active role of local communities denouncing illegal environmental threats (e

  3. Mapping Ecosystem Services in the Jordan Valley, Jordan

    Science.gov (United States)

    Luz, Ana; Marques, Ana; Ribeiro, Inês; Alho, Maria; Catarina Afonso, Ana; Almeida, Erika; Branquinho, Cristina; Talozi, Samer; Pinho, Pedro

    2016-04-01

    In the last decade researchers started using ecosystem services as a new framework to understand the relationships between environment and society. Habitat quality and water quality are related with ecosystem services regulation and maintenance, or even provision. According to the Common International Classification of Ecosystem Services (CICES) both habitat quality and water quality are associated with lifecycle maintenance, habitat and gene pool protection, and water conditions, among others. As there is increased pressure on habitats and rivers especially for agricultural development, mapping and evaluating habitat and water quality has important implications for resource management and conservation, as well as for rural development. Here, we model and map habitat and water quality in the Jordan Valley, Jordan. In this study, we aim to identify and analyse ecosystem services both through 1) habitat quality and 2) water quality modelling using InVest, an integrated valuation of ecosystem services and tradeoffs. The data used in this study mainly includes the LULC, Jordan River watershed and main threats and pollutants in the study area, such as agriculture, industry, fish farms and urbanization. Results suggest a higher pressure on natural habitats in the Northern region of the Jordan Valley, where industry is dominant. Agriculture is present along the Jordan Valley and limits the few natural forested areas. Further, water pollution is mainly concentrated in disposal sites due to the low flow of the Jordan River. Our results can help to identify areas where natural resources and water resource management is most needed in the Jordan Valley. Acknowledgements: Transbasin FP7 project

  4. Climate change and the Lower Fraser Valley. rev. ed.

    International Nuclear Information System (INIS)

    Taylor, E.; Langlois, D.

    2000-01-01

    The climatic changes that are expected to occur in British Columbia's Lower Fraser Valley over the next century were described in this report which included information about the science of climate change and the development of global climate models that provide estimates of global climate for the coming century. The confidence that scientists have in these models was reflected in the fact that most can simulate the important seasonal and geographical large scale features of the global climate, and that many of the large scale changes that are effected by greenhouse gas concentrations can be explained in terms of physical processes which operate around the world. The models also reproduce with reasonable accuracy the variations of climate such as the El Nino phenomena., the cooling due to the Mount Pinatubo eruption in 1991 and the global warming that occurred over the past 100 years. Three climate stations were analyzed in this study to assess the climate change of the Valley. Climatic change is influenced by increased concentrations of greenhouse gases in the atmosphere which in turn cause accelerated global warming. Scientists generally believe that the combustion of fossil fuels and other human activities are a major reason for the increased concentration of carbon dioxide. Plant respiration and the decomposition of organic matter releases 10 times more CO 2 than that released anthropogenically, but these releases are in balance with plant photosynthesis. The rate of warming in the Lower Fraser Valley is uncertain, but climate models suggest it could be about 3 to 4 degrees warming with wetter winters and drier summers by the end of the century. The Valley currently has mild temperatures and high precipitation because of its proximity to the Pacific Oceans and the surrounding mountains. Global warming can have an impact on sea levels along the coast, spring flooding, summer drought, coastal ecosystems, air quality, occurrences of forest fires, and recreation

  5. Structural and functional characteristics of natural and constructed channels draining a reclaimed mountaintop removal and valley fill coal mine

    Science.gov (United States)

    Mountaintop removal and valley fill (MTR/VF) coal mining has altered the landscape of the Central Appalachian region in the United States. The goals of this study were to 1) compare the structure and function of natural and constructed stream channels in forested and MTR/VF catch...

  6. Export of detritus and invertebrate from headwater streams: linking mountaintop removal and valley fill coal mining to downstream receiving waters

    Science.gov (United States)

    Mountaintop removal and valley fill (MTR/VF) coal mining has resulted in large scale alteration of the topography, reduced forest productivity, and burial of headwater streams in the U.S. Central Appalachians. Although MTR/VF coal mining has occurred for several decades and the ...

  7. When the douglas-firs were counted: The beginning of the Forest Survey

    Science.gov (United States)

    Ivan Doig

    1976-01-01

    The wonders which Phil Briegleb remembered from that stint of work - the dark green spill of forest from ridgeline to valley floor, the colonnade of giant boles crowding acre upon acre, the Depression-staving paycheck earned by sizing up this big timber - may have been grand, all right, but no more so than the language which spelled out the project. The Forest Survey...

  8. Livelihood Strategies in Shaxi, Southwest China: Conceptualizing Mountain–Valley Interactions as a Human–Environment System

    Directory of Open Access Journals (Sweden)

    Franz K. Huber

    2015-03-01

    Full Text Available This paper investigates the socio-ecological differences and interactions between upland and lowland areas in Shaxi Valley, Yunnan Province, Southwest China. As an analytical tool we used an extended Human–Environment System Framework by focusing particularly on the dynamics and sustainability of livelihood strategies and mountain–valley interactions. Drawing from household surveys conducted in two mountain and two valley communities in 2005 and 2009, we show that the distinct income gap between mountain and valley households in 2005 ceased to exist in 2009. The main drivers for this development are the local tourist industry, persistent demand for forest resources, as well as local off-farm and seasonal migrant employment.

  9. Does nitrogen and sulfur deposition affect forest productivity?

    Science.gov (United States)

    Brittany A. Johnson; Kathryn B. Piatek; Mary Beth Adams; John R. Brooks

    2010-01-01

    We studied the effects of atmospheric nitrogen and sulfur deposition on forest productivity in a 10-year-old, aggrading forest stand at the Fernow Experimental Forest in Tucker County, WV. Forest productivity was expressed as total aboveground wood biomass, which included stem and branch weight of standing live trees. Ten years after stand regeneration and treatment...

  10. 退耕还林工程驱动下的土地利用变化合理性研究——以云南芒市为例%The Rationality Evaluation of Land Use Changes in the Middle and Low Mountain Basin and Valley Area of Southwest Yunnan Province Driven by the National Project of Converting Farmland to Forest:A Case Study in Luxi City

    Institute of Scientific and Technical Information of China (English)

    杨子生; 韩华丽; 朱玉碧; 赵乔贵

    2011-01-01

    In present study on land use/land cover change (LUCC), rationality analysis and evaluation of land use change has not been taken seriously. In particular, there is hardly any study on the theory and method system for evaluating rationality of land use change. By taking Luxi City as an example, which is located in the middle and low mountainous basin and valley area in southwest Yunnan, this paper has discussed the concept and connotation of rational degree of land use change and constructed the evaluation target, estimation method, and grading standard system for studying rational degree of land use change. Then, based on these, it has quantitatively analyzed and evaluated the rational degree of the change in every land use type and rational degree of the overall land use change driven by the nearly-eight-year Program of Converting Farmland to Forest in Luxi City. It aims to provide basic foundation for promoting the sustainable use of land resources in mountainous areas and scientific implementation of the Program of Converting Farmland to Forest. The evaluation results reveal the following facts: 1 ) During recent eight years, the whole city witnessed land use type changes in a total area of 77602.80 hm2. Rational degree ( RD value) of the change was only 48.98% while the irrational degree (ID value) was 51.02%, making the change at the "moderately rational" level. 2) Among all land use types, farmland, forest and waste grassland had the largest changes. Farmland was mainly changed into forest, garden plot and waste grassland, a result driven by the Program of Converting Farmland to Forest. During recent eight years, the whole city had 19661.07 hm2 of farmland converted to ecological uses. Of which, 18886. 09 hm2 were the farmland suitable for cultivation (farmland that "should not have been converted" ) and only 774. 98 hm2 were the farmland not suitable for cultivation ( farmland that "should be converted"). The nearly-eight-year Program of Converting

  11. Better building of valley fills

    Energy Technology Data Exchange (ETDEWEB)

    Chironis, N.P.

    1980-03-01

    Current US regulations for building valley fills or head of hollow fills to hold excess spoil resulting from contour mining are meeting with considerable opposition, particularly from operators in steep-slope areas. An alternative method has been submitted to the Office of Surface Mining by Virgina. Known as the zoned concept method, it has already been used successfully in building water-holding dams and coal refuse embankments on sloping terrain. The ways in which drainage and seepage are managed are described.

  12. Valley formation by groundwater seepage, pressurized groundwater outbursts and crater-lake overflow in flume experiments with implications for Mars

    Science.gov (United States)

    Marra, Wouter A.; Braat, Lisanne; Baar, Anne W.; Kleinhans, Maarten G.

    2014-04-01

    Remains of fluvial valleys on Mars reveal the former presence of water on the surface. However, the source of water and the hydrological setting is not always clear, especially in types of valleys that are rare on Earth and where we have limited knowledge of the processes involved. We investigated three hydrological scenarios for valley formation on Mars: hydrostatic groundwater seepage, release of pressurized groundwater and crater-lake overflow. Using physical modeling in laboratory experiments and numerical hydrological modeling we quantitatively studied the morphological development and processes involved in channel formation that result from these different sources of water in unconsolidated sediment. Our results show that valleys emerging from seeping groundwater by headward erosion form relatively slowly as fluvial transport takes place in a channel much smaller than the valley. Pressurized groundwater release forms a characteristic source area at the channel head by fluidization processes. This head consist of a pit in case of superlithostatic pressure and may feature small radial channels and collapse features. Valleys emerging from a crater-lake overflow event develop quickly in a run-away process of rim erosion and discharge increase. The valley head at the crater outflow point has a converging fan shape, and the rapid incision of the rim leaves terraces and collapse features. Morphological elements observed in the experiments can help in identifying the formative processes on Mars, when considerations of experimental scaling and lithological characteristics of the martian surface are taken into account. These morphological features might reveal the associated hydrological settings and formative timescales of a valley. An estimate of formative timescale from sediment transport is best based on the final channel dimensions for groundwater seepage valleys and on the valley dimensions for pressurized groundwater release and crater-lake overflow valleys. Our

  13. Management impacts on forest floor and soil organic carbon in northern temperate forests of the US

    Science.gov (United States)

    Coeli M. Hoover

    2011-01-01

    The role of forests in the global carbon cycle has been the subject of a great deal of research recently, but the impact of management practices on forest soil dynamics at the stand level has received less attention. This study used six forest management experimental sites in five northern states of the US to investigate the effects of silvicultural treatments (light...

  14. Durability testing with West Valley borosilicate glass composition- Phase II

    International Nuclear Information System (INIS)

    Macedo, P.B.; Finger, S.M.; Barkatt, A.A.; Pegg, I.L.; Feng, X.; Freeborn, W.P.

    1988-06-01

    This report presents the research performed by the Catholic University of America Vitreous State Laboratory (VSL) during FY 1987 in support of the West Valley Demonstration Project (WVDP) nuclear waste vitrification process. A principal objective of this work is the optimization of the glass composition be used for the vitrification of the liquid high-level waste generated at West Valley during nuclear fuel reprocessing. This report discusses (1) the experimental investigations to optimize the reference glass composition (the current leading candidates are WVCM-50 and ATM-10) for the WVDP vitrification process; (2) the systematic experimental investigation performed to determine the effects of compositional variations in WVCM-50 and WV-205 reference glasses on their viscosity and durability (including initial results of long-term leach tests of WVCM-50 under repository conditions); (3) the development of short-time and predictive leach tests; (4) the development of a process model for the West Valley vitrification process which predicts the range of glass compositions which may be encountered during normal operations and the effects of deviations in process control parameters; and (5) the development of product models for predicting the durability and viscosity of nuclear waste glasses

  15. California's restless giant: the Long Valley Caldera

    Science.gov (United States)

    Hill, David P.; Bailey, Roy A.; Hendley, James W.; Stauffer, Peter H.; Marcaida, Mae

    2014-01-01

    Scientists have monitored geologic unrest in the Long Valley, California, area since 1980. In that year, following a swarm of strong earthquakes, they discovered that the central part of the Long Valley Caldera had begun actively rising. Unrest in the area persists today. The U.S. Geological Survey (USGS) continues to provide the public and civil authorities with current information on the volcanic hazard at Long Valley and is prepared to give timely warnings of any impending eruption.

  16. Impacts of forest management on runoff and erosion

    Science.gov (United States)

    William J. Elliot; Brandon D. Glaza

    2009-01-01

    In a parallel study, ten small watersheds (about 5 ha) were installed in the Priest River Experimental Forest (PREF) in northern Idaho, and another ten were installed in the Boise Basin Experimental Forest (BBEF) in central Idaho. The long-term objective of the study is to compare the effects of different forest management activities on runoff and...

  17. Restoring bottomland hardwood forests: A comparison of four techniques

    Science.gov (United States)

    John A. Stanturf; Emile S. Cardiner; James P. Shepard; Callie J. Schweitzer; C. Jeffrey Portwood; Lamar Dorris

    2004-01-01

    Large-scale afforestation of former agricultural lands in the Lower Mississippi Alluvial Valley (LMAV) is one of the largest forest restoration efforts in the world and continues to attract interest from landowners, policy makers, scientists, and managers. The decision by many landowners to afforest these lands has been aided in part by the increased availability of...

  18. Historical trends in rusty blackbird nonbreeding habitat in forested wetlands

    Science.gov (United States)

    Paul B. Hamel; Diane De Steven; Ted Leininger; Randy. Wilson

    2009-01-01

    Rusty Blackbird (Euphagus carolinus) populations have declined perhaps 95% in the recent past, creating legitimate concern that the species may become endangered. During the nonbreeding period the species occurs predominantly in southern U.S. forested wetland habitats, with concentrations in the Mississippi Alluvial Valley and in the southeastern...

  19. Quantifying flooding regime in floodplain forests to guide river restoration

    Science.gov (United States)

    Christian O. Marks; Keith H. Nislow; Francis J. Magilligan

    2014-01-01

    Determining the flooding regime needed to support distinctive floodplain forests is essential for effective river conservation under the ubiquitous human alteration of river flows characteristic of the Anthropocene Era. At over 100 sites throughout the Connecticut River basin, the largest river system in New England, we characterized species composition, valley and...

  20. Hidden Valley Higgs Decays in the ATLAS detector

    CERN Document Server

    Ciapetti, G

    2009-01-01

    A number of extensions of the Standard Model result in particles that are neutral, weakly-coupled and have macroscopic decay lengths that can be comparable with LHC detector dimensions. These particles represent, from an experimental point of view, a challenge both for the trigger and for the reconstruction capabilities of the ATLAS apparatus. For the purpose of exploring the challenges to the trigger posed by long-lived particles, the Hidden Valley scenario serves as an excellent setting. In this note we present the results of a first study of ATLAS detector performance for some Hidden Valley processes with long-lived, neutral states that decay throughout the detector volume to multi heavy-flavor jets, mainly b-bbar.

  1. Small martian valleys: Pristine and degraded morphology

    International Nuclear Information System (INIS)

    Baker, V.R.; Partridge, J.B.

    1986-01-01

    The equatorial heavily cratered uplands of Mars are dissected by two classes of small valleys that are intimately associated in compound networks. Pristine valleys with steep valley walls preferentially occupy downstream portions of compound basins. Degraded valleys with eroded walls are laterally more extensive and have higher drainage densities than pristine valleys. Morphometric and crater-counting studies indicate that relatively dense drainage networks were emplaced on Mars during the heavy bombardment about 4.0 b.y. ago. Over a period of approximately 10 8 years, these networks were degraded and subsequently invaded by headwardly extending pristine valleys. The pristine valleys locally reactivated the compound networks, probably through sapping processes dependent upon high water tables. Fluvial activity in the heavily cratered uplands generally ceased approximately 3.8--3.9 b.y. ago, coincident with the rapid decline in cratering rates. The relict compound valleys on Mars are morphometrically distinct from most terrestrial drainage systems. The differences might be caused by a Martian valley formation episode characterized by hyperaridity, by inadequate time for network growth, by very permeable rock types, or by a combination of factors

  2. EPA Region 1 - Valley Depth in Meters

    Science.gov (United States)

    Raster of the Depth in meters of EPA-delimited Valleys in Region 1.Valleys (areas that are lower than their neighbors) were extracted from a Digital Elevation Model (USGS, 30m) by finding the local average elevation, subtracting the actual elevation from the average, and selecting areas where the actual elevation was below the average. The landscape was sampled at seven scales (circles of 1, 2, 4, 7, 11, 16, and 22 km radius) to take into account the diversity of valley shapes and sizes. Areas selected in at least four scales were designated as valleys.

  3. A landscape scale valley confinement algorithm: Delineating unconfined valley bottoms for geomorphic, aquatic, and riparian applications

    Science.gov (United States)

    David E. Nagel; John M. Buffington; Sharon L. Parkes; Seth Wenger; Jaime R. Goode

    2014-01-01

    Valley confinement is an important landscape characteristic linked to aquatic habitat, riparian diversity, and geomorphic processes. This report describes a GIS program called the Valley Confinement Algorithm (VCA), which identifies unconfined valleys in montane landscapes. The algorithm uses nationally available digital elevation models (DEMs) at 10-30 m resolution to...

  4. Texas' forests, 2008

    Science.gov (United States)

    James W. Bentley; Consuelo Brandeis; Jason A. Cooper; Christopher M. Oswalt; Sonja N. Oswalt; KaDonna Randolph

    2014-01-01

    This bulletin describes forest resources of the State of Texas at the time of the 2008 forest inventory. This bulletin addresses forest area, volume, growth, removals, mortality, forest health, timber product output, and the economy of the forest sector.

  5. Forest resources of the Lincoln National Forest

    Science.gov (United States)

    John D. Shaw

    2006-01-01

    The Interior West Forest Inventory and Analysis (IWFIA) program of the USDA Forest Service, Rocky Mountain Research Station, as part of its national Forest Inventory and Analysis (FIA) duties, conducted forest resource inventories of the Southwestern Region (Region 3) National Forests. This report presents highlights of the Lincoln National Forest 1997 inventory...

  6. West Valley Demonstration Project, West Valley, New York: Annual report

    International Nuclear Information System (INIS)

    1989-01-01

    Under the West Valley Demonstration Project Act, Public Law 96-368, liquid high-level radioactive waste stored at the Western New York Nuclear Services Center, West Valley, New York, that resulted from spent nuclear fuel reprocessing operations conducted between 1966 and 1972, is to be solidified in borosilicate glass and transported to a federal repository for geologic disposal. A major milestone was reached in May 1988 when the Project began reducing the volume of the liquid high-level waste. By the end of 1988, approximately 15 percent of the initial inventory had been processed into two waste streams. The decontaminated low-level liquid waste is being solidified in cement. The high-level waste stream is being stored in an underground tank pending its incorporation into borosilicate glass. Four tests of the waste glass melter system were completed. These tests confirmed equipment operability, control system reliability, and provided samples of waste glass for durability testing. In mid-1988, the Department validated an integrated cost and schedule plan for activities required to complete the production of the waste borosilicate glass. Design of the radioactive Vitrification Facility continued

  7. The Pocatello Valley, Idaho, earthquake

    Science.gov (United States)

    Rogers, A. M.; Langer, C.J.; Bucknam, R.C.

    1975-01-01

    A Richter magnitude 6.3 earthquake occurred at 8:31 p.m mountain daylight time on March 27, 1975, near the Utah-Idaho border in Pocatello Valley. The epicenter of the main shock was located at 42.094° N, 112.478° W, and had a focal depth of 5.5 km. This earthquake was the largest in the continental United States since the destructive San Fernando earthquake of February 1971. The main shock was preceded by a magnitude 4.5 foreshock on March 26. 

  8. Radwaste challenge at Beaver Valley

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    Duquesne Light Company met the problem of accumulating low-level radioactive waste at its Beaver Valley nuclear plant with an aggressive program to reduce the quantity of contaminated material and demonstrate that the plant was improving its radiological protection. There was also an economic incentive to reduce low-level wastes. The imaginative campaign involved workers in the reduction effort through training and the adoption of practical approaches to reducing the amount of material exposed to radiation that include sorting trash by radiation level and a compacting system. 4 figures

  9. The Owens Valley Millimeter Array

    International Nuclear Information System (INIS)

    Padin, S.; Scott, S.L.; Woody, D.P.; Scoville, N.Z.; Seling, T.V.

    1991-01-01

    The telescopes and signal processing systems of the Owens Valley Millimeter Array are considered, and improvements in the sensitivity and stability of the instrument are characterized. The instrument can be applied to map sources in the 85 to 115 GHz and 218 to 265 GHz bands with a resolution of about 1 arcsec in the higher frequency band. The operation of the array is fully automated. The current scientific programs for the array encompass high-resolution imaging of protoplanetary/protostellar disk structures, observations of molecular cloud complexes associated with spiral structure in nearby galaxies, and observations of molecular structures in the nuclei of spiral and luminous IRAS galaxies. 9 refs

  10. Valley-dependent band structure and valley polarization in periodically modulated graphene

    Science.gov (United States)

    Lu, Wei-Tao

    2016-08-01

    The valley-dependent energy band and transport property of graphene under a periodic magnetic-strained field are studied, where the time-reversal symmetry is broken and the valley degeneracy is lifted. The considered superlattice is composed of two different barriers, providing more degrees of freedom for engineering the electronic structure. The electrons near the K and K' valleys are dominated by different effective superlattices. It is found that the energy bands for both valleys are symmetric with respect to ky=-(AM+ξ AS) /4 under the symmetric superlattices. More finite-energy Dirac points, more prominent collimation behavior, and new crossing points are found for K' valley. The degenerate miniband near the K valley splits into two subminibands and produces a new band gap under the asymmetric superlattices. The velocity for the K' valley is greatly renormalized compared with the K valley, and so we can achieve a finite velocity for the K valley while the velocity for the K' valley is zero. Especially, the miniband and band gap could be manipulated independently, leading to an increase of the conductance. The characteristics of the band structure are reflected in the transmission spectra. The Dirac points and the crossing points appear as pronounced peaks in transmission. A remarkable valley polarization is obtained which is robust to the disorder and can be controlled by the strain, the period, and the voltage.

  11. Sustainable agricultural development in inland valleys

    NARCIS (Netherlands)

    Zwart, S.J.

    2018-01-01

    The inland valley in Africa are common landscapes that have favorable conditions for agricultural production. Compared to the surrounding uplands they are characterized by a relatively high and secure water availability and high soil fertility levels. Inland valleys thus have a high agricultural

  12. Valley dependent transport in graphene L junction

    Science.gov (United States)

    Chan, K. S.

    2018-05-01

    We studied the valley dependent transport in graphene L junctions connecting an armchair lead and a zigzag lead. The junction can be used in valleytronic devices and circuits. Electrons injected from the armchair lead into the junction is not valley polarized, but they can become valley polarized in the zigzag lead. There are Fermi energies, where the current in the zigzag lead is highly valley polarized and the junction is an efficient generator of valley polarized current. The features of the valley polarized current depend sensitively on the widths of the two leads, as well as the number of dimers in the armchair lead, because this number has a sensitive effect on the band structure of the armchair lead. When an external potential is applied to the junction, the energy range with high valley polarization is enlarged enhancing its function as a generator of highly valley polarized current. The scaling behavior found in other graphene devices is also found in L junctions, which means that the results presented here can be extended to junctions with larger dimensions after appropriate scaling of the energy.

  13. Beaver assisted river valley formation

    Science.gov (United States)

    Westbrook, Cherie J.; Cooper, D.J.; Baker, B.W.

    2011-01-01

    We examined how beaver dams affect key ecosystem processes, including pattern and process of sediment deposition, the composition and spatial pattern of vegetation, and nutrient loading and processing. We provide new evidence for the formation of heterogeneous beaver meadows on riverine system floodplains and terraces where dynamic flows are capable of breaching in-channel beaver dams. Our data show a 1.7-m high beaver dam triggered overbank flooding that drowned vegetation in areas deeply flooded, deposited nutrient-rich sediment in a spatially heterogeneous pattern on the floodplain and terrace, and scoured soils in other areas. The site quickly de-watered following the dam breach by high stream flows, protecting the deposited sediment from future re-mobilization by overbank floods. Bare sediment either exposed by scouring or deposited by the beaver flood was quickly colonized by a spatially heterogeneous plant community, forming a beaver meadow. Many willow and some aspen seedlings established in the more heavily disturbed areas, suggesting the site may succeed to a willow carr plant community suitable for future beaver re-occupation. We expand existing theory beyond the beaver pond to include terraces within valleys. This more fully explains how beavers can help drive the formation of alluvial valleys and their complex vegetation patterns as was first postulated by Ruedemann and Schoonmaker in 1938. ?? 2010 John Wiley & Sons, Ltd.

  14. Interaction Induced Quantum Valley Hall Effect in Graphene

    Directory of Open Access Journals (Sweden)

    E. C. Marino

    2015-03-01

    Full Text Available We use pseudo-quantum electrodynamics in order to describe the full electromagnetic interaction of the p electrons in graphene in a consistent 2D formulation. We first consider the effect of this interaction in the vacuum polarization tensor or, equivalently, in the current correlator. This allows us to obtain the T→0 conductivity after a smooth zero-frequency limit is taken in Kubo’s formula. Thereby, we obtain the usual expression for the minimal conductivity plus corrections due to the interaction that bring it closer to the experimental value. We then predict the onset of an interaction-driven spontaneous quantum valley Hall effect below an activation temperature of the order of 2 K. The transverse (Hall valley conductivity is evaluated exactly and shown to coincide with the one in the usual quantum Hall effect. Finally, by considering the effects of pseudo-quantum electrodynamics, we show that the electron self-energy is such that a set of P- and T-symmetric gapped electron energy eigenstates are dynamically generated, in association with the quantum valley Hall effect.

  15. Ethnoecology of Fire: An Experimental Approach in the Ohio Valley

    Science.gov (United States)

    Erin B. Hines; Jan Salick; Elaine Kennedy Sutherland; Todd F. Hutchinson; Steve Sutherland; Steve Sutherland

    2000-01-01

    Native Americans used fire to manipulate nature and directly benefit their survival. Certain plant species, many of which were useful to Native Americans as sources of food, fiber, dye, medicine, and game browse, are adapted to survive and even thrive in post-burn environments. Evidence suggests that Native Americans intentionally set fires to encourage growth and...

  16. Boreal forests

    International Nuclear Information System (INIS)

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

    1997-01-01

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

  17. Predicting the valley physics of silicon quantum dots directly from a device layout

    Science.gov (United States)

    Gamble, John King; Harvey-Collard, Patrick; Jacobson, N. Tobias; Bacewski, Andrew D.; Nielsen, Erik; Montaño, Inès; Rudolph, Martin; Carroll, Malcolm S.; Muller, Richard P.

    Qubits made from electrostatically-defined quantum dots in Si-based systems are excellent candidates for quantum information processing applications. However, the multi-valley structure of silicon's band structure provides additional challenges for the few-electron physics critical to qubit manipulation. Here, we present a theory for valley physics that is predictive, in that we take as input the real physical device geometry and experimental voltage operation schedule, and with minimal approximation compute the resulting valley physics. We present both effective mass theory and atomistic tight-binding calculations for two distinct metal-oxide-semiconductor (MOS) quantum dot systems, directly comparing them to experimental measurements of the valley splitting. We conclude by assessing these detailed simulations' utility for engineering desired valley physics in future devices. Sandia is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the US Department of Energy's National Nuclear Security Administration under Contract No. DE-AC04-94AL85000. The authors gratefully acknowledge support from the Sandia National Laboratories Truman Fellowship Program, which is funded by the Laboratory Directed Research and Development (LDRD) Program.

  18. Oldman river dam mitigation program downstream vegetation project report, Volume II: The potential effects of an operating plan for the Oldman River dam on Riparian cottonwood forests

    Energy Technology Data Exchange (ETDEWEB)

    Mahoney, J.M.

    1993-01-01

    Extensive cottonwood (poplar) forests exist in the Oldman River valley downstream of the Oldman River dam. Studies of similar forests in nearby river valleys and elsewhere on the western prairies have found significant declines of some riparian forests following river damming. This investigation was initiated to determine the causes of cottonwood forest decline downstream from existing dams in southern Alberta; inventory the existing river valley forests in the Oldman Basin; establish study sites in the Oldman River forests to monitor changes in forest status following commissioning of the Oldman River dam, and evaluate the probable impact of proposed operating plans for the Oldman River dam and associated water control structures on downstream forests. This report summarizes the progress made in the analyses of the probable effects on the survival of the forests, including a discussion of the hydrological conditions essential for cottonwood forest regeneration and an explanation of the effects of altering these characteristics on riparian forests; the hydrological alterations expected along various river reaches in the Oldman Basin with the implementation of the proposed OD05 Oldman Dam operating plan; and preliminary analyses of the problem impacts of the OD05 operating plan on the cottonwood forests along these reaches.

  19. Floristic diversity and distribution pattern of plant communities along altitudinal gradient in Sangla Valley, Northwest Himalaya.

    Science.gov (United States)

    Sharma, Pankaj; Rana, J C; Devi, Usha; Randhawa, S S; Kumar, Rajesh

    2014-01-01

    Himalayas are globally important biodiversity hotspots and are facing rapid loss in floristic diversity and changing pattern of vegetation due to various biotic and abiotic factors. This has necessitated the qualitative and quantitative assessment of vegetation here. The present study was conducted in Sangla Valley of northwest Himalaya aiming to assess the structure of vegetation and its trend in the valley along the altitudinal gradient. In the forest and alpine zones of the valley, 15 communities were recorded. Study revealed 320 species belonging to 199 genera and 75 families. Asteraceae, Rosaceae, Apiaceae, and Ranunculaceae were dominant. Among genera, Artemisia followed by Polygonum, Saussurea, Berberis, and Thalictrum were dominant. Tree and shrub's density ranged from 205 to 600 and from 105 to 1030 individual per hectare, respectively, whereas herbs ranged from 22.08 to 78.95 individual/m(2). Nearly 182 species were native to the Himalaya. Maximum altitudinal distribution of few selected climate sensitive species was found to be highest in northeast and north aspects. This study gives an insight into the floristic diversity and community structure of the fragile Sangla Valley which was hitherto not available.

  20. Anthropogenic Disturbances Create a New Vegetation Toposequence in the Gatineau River Valley, Quebec

    Directory of Open Access Journals (Sweden)

    Jason Laflamme

    2016-10-01

    Full Text Available This study measured changes in forest composition that have occurred since the preindustrial era along the toposequence of the Gatineau River Valley, Quebec, Canada (5650 km2, based on survey records prior to colonization (1804–1864 and recent forest inventories (1982–2006. Changes in forest cover composition over time were found to be specific to toposequence position. Maple and red oak are now more frequent on upper toposequence positions (+26%, +21%, respectively, whereas yellow birch, eastern hemlock, and American beech declined markedly (−34% to −17%. Poplar is more frequent throughout the landscape, but particularly on mid-toposequence positions (+40%. In contrast, white pine, frequent on all toposequence positions in the preindustrial forest, is now confined to shallow and coarse-textured soils (−20%. The preindustrial forest types of the study area were mostly dominated by maple, yellow birch, and beech, with strong components of white pine, hemlock, and eastern white cedar, either as dominant or codominant species. In a context of ongoing anthropogenic disturbances and environmental changes, it is probably not possible to restore many of these types, except where targeted silvicultural interventions could increase the presence of certain species. The new forest types observed should be managed to ensure continuity of vital ecosystem services and functions as disturbance regimes evolve.

  1. Linking plant hydraulics and beta diversity in tropical forests

    Energy Technology Data Exchange (ETDEWEB)

    Christoffersen, Bradley [Earth and Environmental Sciences, Los Alamos National Laboratory, Los Alamos NM 87545 USA; Meir, Patrick [School of GeoSciences, University of Edinburgh, Edinburgh EH9 3FE UK; Research School of Biology, Australian National University, Canberra ACT 2601 Australia; McDowell, Nate G. [Pacific Northwest National Laboratory, Richland WA 99352 USA

    2017-05-31

    In tropical forests, studies of xylem traits governing water transport through plants, or ‘hydraulic architecture’ (Tyree et al., 1991), and changes in species composition across environmental gradients, or ‘beta diversity’ (Gentry, 1988; Ackerly & Cornwell, 2007), have progressedmostly in parallel until recently (Hao et al., 2008; Bartlett et al., 2016). In this issue of New Phytologist, Cosme et al. (pp. 000–5 000) present a timely contribution to the intersection of plant hydraulic architecture (HA) with trait-based community ecology. Building on previous biogeographical work that demonstrated shifts in species composition (beta diversity) across a gradient from valleys to plateaus in central Amazonia (Schietti et al., 2014), Cosme et al. explore how variation in HA might underpin this sorting, sampling pairs of congeneric species restrictedmostly to either plateau or valley habitats. Valley species had significantly lower wood density and higher hydraulically-weighted vessel diameter and vessel area. By contrast, trees with some of the largest hydraulically-weighted vessel diameters existed in tall, deciduous plateau species, while the leaf: sapwood area ratio decreased with height in valley but not plateau species. These intriguing results suggest that species differentiation in water transport traits mediate edaphic filtering along the valley-toplateau gradient, in contrast to previous work where wood mechanical support mediated valley-to-plateau environmental filtering (Fortunel et al., 2014).

  2. A real options model to assess the role of flexibility in forestry and agroforestry adoption and disadoption in the Lower Mississippi Alluvial Valley

    Science.gov (United States)

    Gregory E. Frey; D. Evan Mercer; Frederick W. Cubbage; Robert C. Abt

    2013-01-01

    Efforts to restore the Lower Mississippi Alluvial Valley’s forests have not achieved desired levels of ecosystem services production.We examined how the variability of returns and the flexibility to change or postpone decisions (option value) affects the economic potential of forestry and agroforestry systems to keep private land in production while still providing...

  3. Valley-filtered edge states and quantum valley Hall effect in gated bilayer graphene.

    Science.gov (United States)

    Zhang, Xu-Long; Xu, Lei; Zhang, Jun

    2017-05-10

    Electron edge states in gated bilayer graphene in the quantum valley Hall (QVH) effect regime can carry both charge and valley currents. We show that an interlayer potential splits the zero-energy level and opens a bulk gap, yielding counter-propagating edge modes with different valleys. A rich variety of valley current states can be obtained by tuning the applied boundary potential and lead to the QVH effect, as well as to the unbalanced QVH effect. A method to individually manipulate the edge states by the boundary potentials is proposed.

  4. Forest science in the South - 2002

    Science.gov (United States)

    Southern Research Station USDA Forest Service

    2003-01-01

    Forest Science in the South includes the Southern Station's accomplishments, emerging research priorities, and products - journal articles, books, Station publications, presentations, and Web postings. This report details budget allocations, highlights collaborative research, includes a directory of research units and experimental forests, and summarizes...

  5. Vegetation - San Felipe Valley [ds172

    Data.gov (United States)

    California Natural Resource Agency — This Vegetation Map of the San Felipe Valley Wildlife Area in San Diego County, California is based on vegetation samples collected in the field in 2002 and 2005 and...

  6. Babesiosis in Lower Hudson Valley, New York

    Centers for Disease Control (CDC) Podcasts

    This podcast discusses a study about an increase in babesiosis in the Lower Hudson Valley of New York state. Dr. Julie Joseph, Assistant Professor of Medicine at New York Medical College, shares details of this study.

  7. Meie mees Silicon Valleys / Kertu Ruus

    Index Scriptorium Estoniae

    Ruus, Kertu, 1977-

    2007-01-01

    Ilmunud ka: Delovõje Vedomosti 5. dets. lk. 4. Peaminister Andrus Ansip avas Eesti Ettevõtluse Sihtasutuse esinduse Silicon Valley pealinnas San Joses. Vt. samas: Ränioru kliima on tehnoloogiasõbralik; Andrus Viirg

  8. Meie ingel Silicon Valleys / Raigo Neudorf

    Index Scriptorium Estoniae

    Neudorf, Raigo

    2008-01-01

    Ettevõtluse Arendamise Sihtasutuse esinduse töölepanekust USAs Silicon Valleys räägib esinduse juht Andrus Viirg. Vt. ka: Eestlasi leidub San Franciscos omajagu; Muljetavaldav karjäär; USAga ammune tuttav

  9. Burrowing Owl - Palo Verde Valley [ds197

    Data.gov (United States)

    California Natural Resource Agency — These burrowing owl observations were collected during the spring and early summer of 1976 in the Palo Verde Valley, eastern Riverside County, California. This is an...

  10. Quantum spin/valley Hall effect and topological insulator phase transitions in silicene

    KAUST Repository

    Tahir, M.

    2013-04-26

    We present a theoretical realization of quantum spin and quantum valley Hall effects in silicene. We show that combination of an electric field and intrinsic spin-orbit interaction leads to quantum phase transitions at the charge neutrality point. This phase transition from a two dimensional topological insulator to a trivial insulating state is accompanied by a quenching of the quantum spin Hall effect and the onset of a quantum valley Hall effect, providing a tool to experimentally tune the topological state of silicene. In contrast to graphene and other conventional topological insulators, the proposed effects in silicene are accessible to experiments.

  11. Quantum spin/valley Hall effect and topological insulator phase transitions in silicene

    KAUST Repository

    Tahir, M.; Manchon, Aurelien; Sabeeh, K.; Schwingenschlö gl, Udo

    2013-01-01

    We present a theoretical realization of quantum spin and quantum valley Hall effects in silicene. We show that combination of an electric field and intrinsic spin-orbit interaction leads to quantum phase transitions at the charge neutrality point. This phase transition from a two dimensional topological insulator to a trivial insulating state is accompanied by a quenching of the quantum spin Hall effect and the onset of a quantum valley Hall effect, providing a tool to experimentally tune the topological state of silicene. In contrast to graphene and other conventional topological insulators, the proposed effects in silicene are accessible to experiments.

  12. Illinois' Forests 2005

    Science.gov (United States)

    Susan J. Crocker; Gary J. Brand; Brett J. Butler; David E. Haugen; Dick C. Little; Dacia M. Meneguzzo; Charles H. Perry; Ronald J. Piva; Barry T. Wilson; Christopher W. Woodall

    2009-01-01

    The first full, annualized inventory of Illinois' forests reports more than 4.5 million acres of forest land with an average of 459 trees per acre. Forest land is dominated by oak/hickory forest types, which occupy 65 percent of total forest land area. Seventy-two percent of forest land consists of sawtimber, 20 percent contains poletimber, and 8 percent contains...

  13. Minnesota's Forests 2008

    Science.gov (United States)

    Patrick D. Miles; David Heinzen; Manfred E. Mielke; Christopher W. Woodall; Brett J. Butler; Ron J. Piva; Dacia M. Meneguzzo; Charles H. Perry; Dale D. Gormanson; Charles J. Barnett

    2011-01-01

    The second full annual inventory of Minnesota's forests reports 17 million acres of forest land with an average volume of more than 1,000 cubic feet per acre. Forest land is dominated by the aspen forest type, which occupies nearly 30 percent of the total forest land area. Twenty-eight percent of forest land consists of sawtimber, 35 percent poletimber, 35 percent...

  14. Effects of national forest-management regimes on unprotected forests of the Himalaya.

    Science.gov (United States)

    Brandt, Jodi S; Allendorf, Teri; Radeloff, Volker; Brooks, Jeremy

    2017-12-01

    Globally, deforestation continues, and although protected areas effectively protect forests, the majority of forests are not in protected areas. Thus, how effective are different management regimes to avoid deforestation in non-protected forests? We sought to assess the effectiveness of different national forest-management regimes to safeguard forests outside protected areas. We compared 2000-2014 deforestation rates across the temperate forests of 5 countries in the Himalaya (Bhutan, Nepal, China, India, and Myanmar) of which 13% are protected. We reviewed the literature to characterize forest management regimes in each country and conducted a quasi-experimental analysis to measure differences in deforestation of unprotected forests among countries and states in India. Countries varied in both overarching forest-management goals and specific tenure arrangements and policies for unprotected forests, from policies emphasizing economic development to those focused on forest conservation. Deforestation rates differed up to 1.4% between countries, even after accounting for local determinants of deforestation, such as human population density, market access, and topography. The highest deforestation rates were associated with forest policies aimed at maximizing profits and unstable tenure regimes. Deforestation in national forest-management regimes that emphasized conservation and community management were relatively low. In India results were consistent with the national-level results. We interpreted our results in the context of the broader literature on decentralized, community-based natural resource management, and our findings emphasize that the type and quality of community-based forestry programs and the degree to which they are oriented toward sustainable use rather than economic development are important for forest protection. Our cross-national results are consistent with results from site- and regional-scale studies that show forest-management regimes that

  15. Electrical valley filtering in transition metal dichalcogenides

    Science.gov (United States)

    Hsieh, Tzu-Chi; Chou, Mei-Yin; Wu, Yu-Shu

    2018-03-01

    This work investigates the feasibility of electrical valley filtering for holes in transition metal dichalcogenides. We look specifically into the scheme that utilizes a potential barrier to produce valley-dependent tunneling rates, and perform the study with both a k .p -based analytic method and a recursive Green's function-based numerical method. The study yields the transmission coefficient as a function of incident energy and transverse wave vector, for holes going through lateral quantum barriers oriented in either armchair or zigzag directions, in both homogeneous and heterogeneous systems. The main findings are the following: (1) The tunneling current valley polarization increases with increasing barrier width or height; (2) both the valley-orbit interaction and band structure warping contribute to valley-dependent tunneling, with the former contribution being manifest in structures with asymmetric potential barriers, and the latter being orientation dependent and reaching maximum for transmission in the armchair direction; and (3) for transmission ˜0.1 , a tunneling current valley polarization of the order of 10 % can be achieved.

  16. Long-term response of Caribbean palm forests to hurricanes

    Science.gov (United States)

    Ariel Lugo; J.L. Frangi

    2016-01-01

    We studied the response of Prestoea montana (Sierra Palm, hereafter Palm) brakes and a Palm floodplain forest to hurricanes in the Luquillo Experimental Forest in Puerto Rico. Over a span of 78 years, 3 hurricanes passed over the study sites for which we have 64 years of measurements for Palm brakes and 20 years for the Palm floodplain forest. For each stand, species...

  17. The Luquillo Mountains: forest resources and their history

    Science.gov (United States)

    P. L. Weaver

    2012-01-01

    This report presents an overview of the El Yunque National Forest, which is also designated as Luquillo Experimental Forest, in northeastern Puerto Rico. The principal topics include the environmental setting (geology, soils, and climate), environmental gradients, arborescent flora, vertebrate fauna, and forest management (i.e., plantations, silvicultural operations,...

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

    Science.gov (United States)

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

    2012-01-01

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

  19. Forest insurance

    Science.gov (United States)

    Ellis T. Williams

    1949-01-01

    Standing timber is one of the few important kinds of property that are not generally covered by insurance. Studies made by the Forest Service and other agencies have indicated that the risks involved in the insurance of timber are not unduly great, provided they can be properly distributed. Such studies, however, have thus far failed to induce any notable development...

  20. Forest Imaging

    Science.gov (United States)

    1992-01-01

    NASA's Technology Applications Center, with other government and academic agencies, provided technology for improved resources management to the Cibola National Forest. Landsat satellite images enabled vegetation over a large area to be classified for purposes of timber analysis, wildlife habitat, range measurement and development of general vegetation maps.

  1. Global demand for gold is another threat for tropical forests

    International Nuclear Information System (INIS)

    Alvarez-Berríos, Nora L; Mitchell Aide, T

    2015-01-01

    The current global gold rush, driven by increasing consumption in developing countries and uncertainty in financial markets, is an increasing threat for tropical ecosystems. Gold mining causes significant alteration to the environment, yet mining is often overlooked in deforestation analyses because it occupies relatively small areas. As a result, we lack a comprehensive assessment of the spatial extent of gold mining impacts on tropical forests. In this study, we provide a regional assessment of gold mining deforestation in the tropical moist forest biome of South America. Specifically, we analyzed the patterns of forest change in gold mining sites between 2001 and 2013, and evaluated the proximity of gold mining deforestation to protected areas (PAs). The forest cover maps were produced using the Land Mapper web application and images from the MODIS satellite MOD13Q1 vegetation indices 250 m product. Annual maps of forest cover were used to model the incremental change in forest in ∼1600 potential gold mining sites between 2001–2006 and 2007–2013. Approximately 1680 km 2 of tropical moist forest was lost in these mining sites between 2001 and 2013. Deforestation was significantly higher during the 2007–2013 period, and this was associated with the increase in global demand for gold after the international financial crisis. More than 90% of the deforestation occurred in four major hotspots: Guianan moist forest ecoregion (41%), Southwest Amazon moist forest ecoregion (28%), Tapajós–Xingú moist forest ecoregion (11%), and Magdalena Valley montane forest and Magdalena–Urabá moist forest ecoregions (9%). In addition, some of the more active zones of gold mining deforestation occurred inside or within 10 km of ∼32 PAs. There is an urgent need to understand the ecological and social impacts of gold mining because it is an important cause of deforestation in the most remote forests in South America, and the impacts, particularly in aquatic systems

  2. Conduction-band valley spin splitting in single-layer H-T l2O

    Science.gov (United States)

    Ma, Yandong; Kou, Liangzhi; Du, Aijun; Huang, Baibiao; Dai, Ying; Heine, Thomas

    2018-02-01

    Despite numerous studies, coupled spin and valley physics is currently limited to two-dimensional (2D) transition-metal dichalcogenides (TMDCs). Here, we predict an exceptional 2D valleytronic material associated with the spin-valley coupling phenomena beyond 2D TMDCs—single-layer (SL) H-T l2O . It displays large valley spin splitting (VSS), significantly larger than that of 2D TMDCs, and a finite band gap, which are both critically attractive for the integration of valleytronics and spintronics. More importantly, in sharp contrast to all the experimentally confirmed 2D valleytronic materials, where the strong valence-band VSS (0.15-0.46 eV) supports the spin-valley coupling, the VSS in SL H-T l2O is pronounced in its conduction band (0.61 eV), but negligibly small in its valence band (21 meV), thus opening a way for manipulating the coupled spin and valley physics. Moreover, SL H-T l2O possesses extremely high carrier mobility, as large as 9.8 ×103c m2V-1s-1 .

  3. Topological Valley Transport in Two-dimensional Honeycomb Photonic Crystals.

    Science.gov (United States)

    Yang, Yuting; Jiang, Hua; Hang, Zhi Hong

    2018-01-25

    Two-dimensional photonic crystals, in analogy to AB/BA stacking bilayer graphene in electronic system, are studied. Inequivalent valleys in the momentum space for photons can be manipulated by simply engineering diameters of cylinders in a honeycomb lattice. The inequivalent valleys in photonic crystal are selectively excited by a designed optical chiral source and bulk valley polarizations are visualized. Unidirectional valley interface states are proved to exist on a domain wall connecting two photonic crystals with different valley Chern numbers. With the similar optical vortex index, interface states can couple with bulk valley polarizations and thus valley filter and valley coupler can be designed. Our simple dielectric PC scheme can help to exploit the valley degree of freedom for future optical devices.

  4. The Sabah Biodiversity Experiment: a long-term test of the role of tree diversity in restoring tropical forest structure and functioning

    Science.gov (United States)

    Hector, Andy; Philipson, Christopher; Saner, Philippe; Chamagne, Juliette; Dzulkifli, Dzaeman; O'Brien, Michael; Snaddon, Jake L.; Ulok, Philip; Weilenmann, Maja; Reynolds, Glen; Godfray, H. Charles J.

    2011-01-01

    Relatively, little is known about the relationship between biodiversity and ecosystem functioning in forests, especially in the tropics. We describe the Sabah Biodiversity Experiment: a large-scale, long-term field study on the island of Borneo. The project aims at understanding the relationship between tree species diversity and the functioning of lowland dipterocarp rainforest during restoration following selective logging. The experiment is planned to run for several decades (from seed to adult tree), so here we focus on introducing the project and its experimental design and on assessing initial conditions and the potential for restoration of the structure and functioning of the study system, the Malua Forest Reserve. We estimate residual impacts 22 years after selective logging by comparison with an appropriate neighbouring area of primary forest in Danum Valley of similar conditions. There was no difference in the alpha or beta species diversity of transect plots in the two forest types, probably owing to the selective nature of the logging and potential effects of competitive release. However, despite equal total stem density, forest structure differed as expected with a deficit of large trees and a surfeit of saplings in selectively logged areas. These impacts on structure have the potential to influence ecosystem functioning. In particular, above-ground biomass and carbon pools in selectively logged areas were only 60 per cent of those in the primary forest even after 22 years of recovery. Our results establish the initial conditions for the Sabah Biodiversity Experiment and confirm the potential to accelerate restoration by using enrichment planting of dipterocarps to overcome recruitment limitation. What role dipterocarp diversity plays in restoration only will become clear with long-term results. PMID:22006970

  5. Disruption of calcium nutrition at Hubbard Brook Experimental Forest (New Hampshire) alters the health and productivity of red spruce and sugar maple trees and provides lessons pertinent to other sites and regions

    Science.gov (United States)

    Paul G. Schaberg; Gary J. Hawley

    2010-01-01

    Pollution-induced acidification and other anthropogenic factors are leaching calcium (Ca) and mobilizing aluminum (Al) in many forest soils. Because Ca is an essential nutrient and Al is a potential toxin, resulting depletions of Ca and increases in available Al may significantly alter the health and productivity of forest trees. Controlled experiments on red spruce (...

  6. Late Quaternary pollen records from the Lower Cobb Valley and adjacent areas, north-west Nelson, New Zealand

    International Nuclear Information System (INIS)

    Shulmeister, J.; McLea, W.L.; Singer, C.; McKay, R.M.; Hosie, C.

    2003-01-01

    Ten pollen records from the Cobb Valley and adjacent areas in North-West Nelson are described. Collectively they provide a vegetation record extending from the Last Glacial Maximum to the present day. During the Last Glacial Maximum the uplands of North-West Nelson were glaciated. By about 17,000 radiocarbon years BP ice had retreated some distance up the Cobb River Valley and a podocarp heath and tussockland vegetation covered non-glaciated areas. By 14,000 radiocarbon years BP, the valley floor and adjacent lower ridges were occupied by montane podocarp forest dominated by Phyllocladus and Halocarpus. Beech forest expanded into some sites as early as 13,000 yr BP but the modern beech cover was not established until the Holocene. Forest cover has fluctuated in response to disturbance over the Holocene, but the most significant recent change, which is related to clearing for pastoralism in the last two centuries, has had surprisingly little impact on the pollen records. (author). 40 refs., 11 figs., 1 tab

  7. Combating Forest Corruption: the Forest Integrity Network

    NARCIS (Netherlands)

    Gupta, A.; Siebert, U.

    2004-01-01

    This article describes the strategies and activities of the Forest Integrity Network. One of the most important underlying causes of forest degradation is corruption and related illegal logging. The Forest Integrity Network is a timely new initiative to combat forest corruption. Its approach is to

  8. Forest ownership dynamics of southern forests

    Science.gov (United States)

    Brett J. Butler; David N. Wear

    2013-01-01

    Key FindingsPrivate landowners hold 86 percent of the forest area in the South; two-thirds of this area is owned by families or individuals.Fifty-nine percent of family forest owners own between 1 and 9 acres of forest land, but 60 percent of family-owned forests are in holdings of 100 acres or more.Two-...

  9. Aquatic habitats of Canaan Valley, West Virginia: Diversity and environmental threats

    Science.gov (United States)

    Snyder, C.D.; Young, J.A.; Stout, B. M.

    2006-01-01

    We conducted surveys of aquatic habitats during the spring and summer of 1995 in Canaan Valley, WV, to describe the diversity of aquatic habitats in the valley and identify issues that may threaten the viability of aquatic species. We assessed physical habitat and water chemistry of 126 ponds and 82 stream sites, and related habitat characteristics to landscape variables such as geology and terrain. Based on our analyses, we found two issues likely to affect the viability of aquatic populations in the valley. The first issue was acid rain and the extent to which it potentially limits the distribution of aquatic and semi-aquatic species, particularly in headwater portions of the watershed. We estimate that nearly 46%, or 56 kilometers of stream, had pH levels that would not support survival and reproduction of Salvelinuw fontinalis (brook trout), one of the most acid-tolerant fishes in the eastern US. The second issue was the influence of Castor canadensis (beaver) activity. In the Canaan Valley State Park portion of the valley, beaver have transformed 4.7 kilometers of stream (approximately 17% of the total) to pond habitat through their dam building. This has resulted in an increase in pond habitat, a decrease in stream habitat, and a fragmented stream network (i.e., beaver ponds dispersed among stream reaches). In addition, beaver have eliminated an undetermined amount of forested riparian area through their foraging activities. Depending on the perspective, beaver-mediated changes can be viewed as positive or negative. Increases in pond habitat may increase habitat heterogeneity with consequent increases in biological diversity. In contrast, flooding associated with beaver activity may eliminate lowland wetlands and associated species, create barriers to fish dispersal, and possibly contribute to low dissolved oxygen levels in the Blackwater River. We recommend that future management strategies for the wildlife refuge be viewed in the context of these two issues

  10. Christmas Valley Renewable Energy Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Del Mar, Robert [Oregon Department of Energy, Salem, OR (United States)

    2017-05-22

    In partnership with the Oregon Military Department, the Department of Energy used the award to assess and evaluate renewable resources in a 2,622-acre location in Lake County, central Oregon, leading to future development of up to 200 MW of solar electricity. In partnership with the Oregon Military Department, the Department of Energy used the award to assess and evaluate renewable resources in a 2,622-acre location in Lake County, central Oregon, leading to future development of up to 200 MW of solar electricity. The Oregon Military Department (Military) acquired a large parcel of land located in south central Oregon. The land was previously owned by the US Air Force and developed for an Over-the-Horizon Backscatter Radar Transmitter Facility, located about 10 miles east of the town of Christmas Valley. The Military is investigating a number of uses for the site, including Research and Development (R&D) laboratory, emergency response, military operations, developing renewable energy and related educational programs. One of the key potential uses would be for a large scale solar photovoltaic power plant. This is an attractive use because the site has excellent solar exposure; an existing strong electrical interconnection to the power grid; and a secure location at a moderate cost per acre. The project objectives include: 1. Site evaluation 2. Research and Development (R&D) facility analysis 3. Utility interconnection studies and agreements 4. Additional on-site renewable energy resources analysis 5. Community education, outreach and mitigation 6. Renewable energy and emergency readiness training program for veterans

  11. The role of selected soil fauna as predators of Apethymus abdominalis Lep. (Hymenoptera: Tenthredinidae) in oak forests in the District Caiuti, Romania

    Science.gov (United States)

    C. Ciornei; N. Popa; L. Ciuca; C. Rang

    2003-01-01

    The present study was initiated in 2001 in the oak forests from Trotus valley (Forest District Caiucti - Bacau, Romania) which were heavily infested by oak sawflies Apethymus abdominalis Lep. (Hymenoptera: Tenthredinidae), in order to understand better the role of soil-inhabitating predators in population regulation of this pest.

  12. Remote sensing applications in agriculture and forestry. Applications of aerial photography and ERTS data to agricultural, forest and water resources management

    Science.gov (United States)

    1973-01-01

    Remote sensing techniques are being used in Minnesota to study: (1) forest disease detection and control; (2) water quality indicators; (3) forest vegetation classification and management; (4) detection of saline soils in the Red River Valley; (5) corn defoliation; and (6) alfalfa crop productivity. Results of progress, and plans for future work in these areas, are discussed.

  13. Plants and butterflies of a small urban preserve in the Central Valley of Costa Rica

    OpenAIRE

    Kenji Nishida; Ichiro Nakamura; Carlos O Morales

    2009-01-01

    Costa Rica’s most populated area, the Central valley, has lost much of its natural habitat, and the little that remains has been altered to varying degrees. Yet few studies have been conducted to assess the need for conservation in this area. We present preliminary inventories of plants, butterflies, and day-flying moths of the Reserva Ecológica Leonelo Oviedo (RELO), a small Premontane Moist Forest preserve within the University of Costa Rica campus, located in the urbanized part of the vall...

  14. Can forest watershed management mitigate climate change impacts on water resources?

    Science.gov (United States)

    James M. Vose; Chelcy R. Ford; Stephanie Laseter; Salli Dymond; GE Sun; Mary Beth Adams; Stephen Sebestyen; John Campbell; Charles Luce; Devendra Amatya; Kelly Elder; Tamara. Heartsill-Scalley

    2012-01-01

    Long-term hydrology and climate data from United States Forest Service Experimental Forests and Ranges (EFR) provide critical information on the interactions among climate, streamflow, and forest management practices. We examined the relationships among streamflow responses to climate variation and forest management using long-term data. Analysis of climate data from a...

  15. A comparison of soil-moisture loss from forested and clearcut areas in West Virginia

    Science.gov (United States)

    Charles A. Troendle

    1970-01-01

    Soil-moisture losses from forested and clearcut areas were compared on the Fernow Experimental Forest. As expected, hardwood forest soils lost most moisture while revegetated clearcuttings, clearcuttings, and barren areas lost less, in that order. Soil-moisture losses from forested soils also correlated well with evapotranspiration and streamflow.

  16. Wetland survey of the X-10 Bethel Valley and Melton Valley groundwater operable units at Oak Ridge National Labortory Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    Rosensteel, B.A.

    1996-03-01

    Executive Order 11990, Protection of Wetlands, (May 24, 1977) requires that federal agencies avoid, to the extent possible, adverse impacts associated with the destruction and modification of wetlands and that they avoid direct and indirect support of wetlands development when there is a practicable alternative. In accordance with Department of Energy (DOE) Regulations for Compliance with Floodplains and Wetlands Environmental Review Requirements (Subpart B, 10 CFR 1022.11), surveys for wetland presence or absence were conducted in both the Melton Valley and the Bethel Valley Groundwater Operable Units (GWOU) on the DOE Oak Ridge Reservation (ORR) from October 1994 through September 1995. As required by the Energy and Water Development Appropriations Act of 1992, wetlands were identified using the criteria and methods set forth in the Wetlands Delineation Manual (Army Corps of Engineers, 1987). Wetlands were identified during field surveys that examined and documented vegetation, soils, and hydrologic evidence. Most of the wetland boundary locations and wetland sizes are approximate. Boundaries of wetlands in Waste Area Grouping (WAG) 2 and on the former proposed site of the Advanced Neutron Source in the upper Melton Branch watershed were located by civil survey during previous wetland surveys; thus, the boundary locations and areal sizes in these areas are accurate. The wetlands were classified according to the system developed by Cowardin et al. (1979) for wetland and deepwater habitats of the United States. A total of 215 individual wetland areas ranging in size from 0.002 ha to 9.97 ha were identified in the Bethel Valley and Melton Valley GWOUs. The wetlands are classified as palustrine forested broad-leaved deciduous (PFO1), palustrine scrub-shrub broad-leaved deciduous (PSS1), and palustrine persistent emergent (PEM1)

  17. Forest fires

    International Nuclear Information System (INIS)

    Fuller, M.

    1991-01-01

    This book examines the many complex and sensitive issues relating to wildland fires. Beginning with an overview of the fires of 1980s, the book discusses the implications of continued drought and considers the behavior of wildland fires, from ignition and spread to spotting and firestorms. Topics include the effects of weather, forest fuels, fire ecology, and the effects of fire on plants and animals. In addition, the book examines firefighting methods and equipment, including new minimum impact techniques and compressed air foam; prescribed burning; and steps that can be taken to protect individuals and human structures. A history of forest fire policies in the U.S. and a discussion of solutions to fire problems around the world completes the coverage. With one percent of the earth's surface burning every year in the last decade, this is a penetrating book on a subject of undeniable importance

  18. Analysis of Mining-induced Valley Closure Movements

    Science.gov (United States)

    Zhang, C.; Mitra, R.; Oh, J.; Hebblewhite, B.

    2016-05-01

    Valley closure movements have been observed for decades in Australia and overseas when underground mining occurred beneath or in close proximity to valleys and other forms of irregular topographies. Valley closure is defined as the inward movements of the valley sides towards the valley centreline. Due to the complexity of the local geology and the interplay between several geological, topographical and mining factors, the underlying mechanisms that actually cause this behaviour are not completely understood. A comprehensive programme of numerical modelling investigations has been carried out to further evaluate and quantify the influence of a number of these mining and geological factors and their inter-relationships. The factors investigated in this paper include longwall positional factors, horizontal stress, panel width, depth of cover and geological structures around the valley. It is found that mining in a series passing beneath the valley dramatically increases valley closure, and mining parallel to valley induces much more closure than other mining orientations. The redistribution of horizontal stress and influence of mining activity have also been recognised as important factors promoting valley closure, and the effect of geological structure around the valley is found to be relatively small. This paper provides further insight into both the valley closure mechanisms and how these mechanisms should be considered in valley closure prediction models.

  19. Dispersal of forest insects

    Science.gov (United States)

    Mcmanus, M. L.

    1979-01-01

    Dispersal flights of selected species of forest insects which are associated with periodic outbreaks of pests that occur over large contiguous forested areas are discussed. Gypsy moths, spruce budworms, and forest tent caterpillars were studied for their massive migrations in forested areas. Results indicate that large dispersals into forested areas are due to the females, except in the case of the gypsy moth.

  20. South Dakota's forests 2005

    Science.gov (United States)

    Ronald J. Piva; W. Keith Moser; Douglas D. Haugan; Gregory J. Josten; Gary J. Brand; Brett J. Butler; Susan J. Crocker; Mark H. Hansen; Dacia M. Meneguzzo; Charles H. Perry; Christopher W. Woodall

    2009-01-01

    The first completed annual inventory of South Dakota's forests reports almost 1.7 million acres of forest land. Softwood forests make up 74 percent of the total forest land area; the ponderosa pine forest type by itself accounts for 69 percent of the total.

  1. Forest report 2016

    International Nuclear Information System (INIS)

    2016-01-01

    This forest condition report of Hesse (Germany) includes the following topics: forest condition survey for all tree species, forest in the in the Rhine-Main area, weather and climate, soil water balance and drought stress, insects and fungi, Forestry Environment Monitoring, infiltrated substances, main results of Forest soil survey in Hesse (BZE II), the substrate group red sandstone, heavy metal contamination of forests.

  2. Mapping Forest Inventory and Analysis forest land use: timberland, reserved forest land, and other forest land

    Science.gov (United States)

    Mark D. Nelson; John Vissage

    2007-01-01

    The Forest Inventory and Analysis (FIA) program produces area estimates of forest land use within three subcategories: timberland, reserved forest land, and other forest land. Mapping these subcategories of forest land requires the ability to spatially distinguish productive from unproductive land, and reserved from nonreserved land. FIA field data were spatially...

  3. The lakes of the Jordan Rift Valley

    International Nuclear Information System (INIS)

    Gat, J.R.

    2001-01-01

    This paper presents a summary of the proceedings of a workshop on the Lakes of the Jordan Rift Valley that was held in conjunction with the CRP on The Use of Isotope Techniques in Lake Dynamics Investigations. The paper presents a review of the geological, hydrogeological and physical limnological setting of the lakes in the Jordan Rift Valley, Lake Hula, Lake Kinneret and the Dead Sea. This is complemented by a description of the isotope hydrology of the system that includes the use of a wide range of isotopes: oxygen-18, deuterium, tritium, carbon-14, carbon-13, chlorine isotopes, boron-11 and helium-3/4. Environmental isotope aspects of the salt balances of the lakes, their palaeolimnology and biogeochemical tracers are also presented. The scope of application of isotopic tracers is very broad and provides a clear insight into many aspects of the physical, chemical and biological limnology of the Rift Valley Lakes. (author)

  4. A new Proposal to Mexico Valley Zonification

    Science.gov (United States)

    Flores-Estrella, H. C.; Yussim, S.; Lomnitz, C.

    2004-12-01

    The effects of the Michoacan earthquake (19th September, 1985, Mw 8.1) in Mexico City caused a significant change in the political, social and scientific history, as it was considered the worst seismic disaster ever lived in Mexico. Since then, numerous efforts have been made to understand and determine the parameters that caused the special features registered. One of these efforts had began on 1960 with the work by Marsal and Masari, who published the Mexico Valley seismological and geotechnical zonification (1969), based on gravimetric and shallow borehole data. In this work, we present a revision of the studies that proposed the zonification, a description of the valley geology, and basing on it we propose a new zonification for Mexico Valley.

  5. Geologic summary of the Owens Valley drilling project, Owens and Rose Valleys, Inyo County, California

    International Nuclear Information System (INIS)

    Schaer, D.W.

    1981-07-01

    The Owens Valley Drilling Project consists of eight drill holes located in southwest Inyo County, California, having an aggregate depth of 19,205 feet (5853 m). Project holes penetrated the Coso Formation of upper Pliocene or early Pleistocene age and the Owens Lake sand and lakebed units of the same age. The project objective was to improve the reliability of uranium-potential-resource estimates assigned to the Coso Formation in the Owens Valley region. Uranium-potential-resource estimates for this area in $100 per pound U 3 O 8 forward-cost-category material have been estimatd to be 16,954 tons (15,384 metric tons). This estimate is based partly on project drilling results. Within the Owens Valley project area, the Coso Formation was encountered only in the Rose Valley region, and for this reason Rose Valley is considered to be the only portion of the project area favorable for economically sized uranium deposits. The sequence of sediments contained in the Owens Valley basin is considered to be largely equivalent but lithologically dissimilar to the Coso Formation of Haiwee Ridge and Rose Valley. The most important factor in the concentration of significant amounts of uranium in the rock units investigated appears to be the availability of reducing agents. Significant amounts of reductants (pyrite) were found in the Coso Formation. No organic debris was noted. Many small, disconnected uranium occurrences, 100 to 500 ppM U 3 O 8 , were encountered in several of the holes

  6. Forests and Forest Cover - MDC_NaturalForestCommunity

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — A point feature class of NFCs - Natural Forest Communities. Natural Forest Community shall mean all stands of trees (including their associated understory) which...

  7. Nitrogen saturation in experimental forested watersheds

    Science.gov (United States)

    Ivan J. Fernandez; Mary Beth Adams

    2000-01-01

    Daniel Rutherford is credited with the discovery of nitrogen (N) in 1772. A.L. Lavoisier, the 18th century French chemist, called this element "azote" which translates to "without life" because free N is incapable of supporting life: a fitting name for this element given the paradoxes it presents to society and its role in global ecology.

  8. Groundwater quality in Coachella Valley, California

    Science.gov (United States)

    Dawson, Barbara J. Milby; Belitz, Kenneth

    2012-01-01

    Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State’s groundwater quality and increases public access to groundwater-quality information. Coachella Valley is one of the study areas being evaluated. The Coachella study area is approximately 820 square miles (2,124 square kilometers) and includes the Coachella Valley groundwater basin (California Department of Water Resources, 2003). Coachella Valley has an arid climate, with average annual rainfall of about 6 inches (15 centimeters). The runoff from the surrounding mountains drains to rivers that flow east and south out of the study area to the Salton Sea. Land use in the study area is approximately 67 percent (%) natural, 21% agricultural, and 12% urban. The primary natural land cover is shrubland. The largest urban areas are the cities of Indio and Palm Springs (2010 populations of 76,000 and 44,000, respectively). Groundwater in this basin is used for public and domestic water supply and for irrigation. The main water-bearing units are gravel, sand, silt, and clay derived from surrounding mountains. The primary aquifers in Coachella Valley are defined as those parts of the aquifers corresponding to the perforated intervals of wells listed in the California Department of Public Health database. Public-supply wells in Coachella Valley are completed to depths between 490 and 900 feet (149 to 274 meters), consist of solid casing from the land surface to a depth of 260 to 510 feet (79 to 155 meters), and are screened or perforated below the solid casing. Recharge to the groundwater system is primarily runoff from the surrounding mountains, and by direct infiltration of irrigation. The primary sources of discharge are pumping wells, evapotranspiration, and underflow to

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

    Science.gov (United States)

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

    2011-09-01

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

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

    Directory of Open Access Journals (Sweden)

    S. P. S. Kushwaha

    2012-09-01

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

  11. Direct measurement of exciton valley coherence in monolayer WSe2

    KAUST Repository

    Hao, Kai; Moody, Galan; Wu, Fengcheng; Dass, Chandriker Kavir; Xu, Lixiang; Chen, Chang Hsiao; Sun, Liuyang; Li, Ming-yang; Li, Lain-Jong; MacDonald, Allan H.; Li, Xiaoqin

    2016-01-01

    In crystals, energy band extrema in momentum space can be identified by a valley index. The internal quantum degree of freedom associated with valley pseudospin indices can act as a useful information carrier, analogous to electronic charge

  12. Goldstone-Apple Valley Radio Telescope System Theory of Operation

    Science.gov (United States)

    Stephan, George R.

    1997-01-01

    The purpose of this learning module is to enable learners to describe how the Goldstone-Apple Valley Radio Telescope (GAVRT) system functions in support of Apple Valley Science and Technology Center's (AVSTC) client schools' radio astronomy activities.

  13. Mechanical control over valley magnetotransport in strained graphene

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Ning, E-mail: maning@stu.xjtu.edu.cn [Department of Physics, MOE Key Laboratory of Advanced Transducers and Intelligent Control System, Taiyuan University of Technology, Taiyuan 030024 (China); Department of Applied Physics, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, Xi' an Jiaotong University, Xi' an 710049 (China); Zhang, Shengli, E-mail: zhangsl@mail.xjtu.edu.cn [Department of Applied Physics, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, Xi' an Jiaotong University, Xi' an 710049 (China); Liu, Daqing, E-mail: liudq@cczu.edu.cn [School of Mathematics and Physics, Changzhou University, Changzhou 213164 (China)

    2016-05-06

    Recent experiments report that the graphene exhibits Landau levels (LLs) that form in the presence of a uniform strain pseudomagnetic field with magnitudes up to hundreds of tesla. We further reveal that the strain removes the valley degeneracy in LLs, and leads to a significant valley polarization with inversion symmetry broken. This accordingly gives rise to the well separated valley Hall plateaus and Shubnikov–de Haas oscillations. These effects are absent in strainless graphene, and can be used to generate and detect valley polarization by mechanical means, forming the basis for the new paradigm “valleytronics” applications. - Highlights: • We explore the mechanical strain effects on the valley magnetotransport in graphene. • We analytically derive the dc collisional and Hall conductivities under strain. • The strain removes the valley degeneracy in Landau levels. • The strain causes a significant valley polarization with inversion symmetry broken. • The strain leads to the well separated valley Hall and Shubnikov–de Haas effects.

  14. The Health Valley: Global Entrepreneurial Dynamics.

    Science.gov (United States)

    Dubuis, Benoit

    2014-12-01

    In the space of a decade, the Lake Geneva region has become the Health Valley, a world-class laboratory for discovering and developing healthcare of the future. Through visionary individuals and thanks to exceptional infrastructure this region has become one of the most dynamic in the field of innovation, including leading scientific research and exceptional actors for the commercialization of academic innovation to industrial applications that will improve the lives of patients and their families. Here follows the chronicle of a spectacular expansion into the Health Valley.

  15. Solar energy innovation and Silicon Valley

    Science.gov (United States)

    Kammen, Daniel M.

    2015-03-01

    The growth of the U. S. and global solar energy industry depends on a strong relationship between science and engineering innovation, manufacturing, and cycles of policy design and advancement. The mixture of the academic and industrial engine of innovation that is Silicon Valley, and the strong suite of environmental policies for which California is a leader work together to both drive the solar energy industry, and keep Silicon Valley competitive as China, Europe and other area of solar energy strength continue to build their clean energy sectors.

  16. Clean Cities Award Winning Coalition: Coachella Valley

    Energy Technology Data Exchange (ETDEWEB)

    ICF Kaiser

    1999-05-20

    Southern California's Coachella Valley became a Clean Cities region in 1996. Since then, they've made great strides. SunLine Transit, the regional public transit provider, was the first transit provider to replace its entire fleet with compressed natural gas buses. They've also built the foundation for a nationally recognized model in the clean air movement, by partnering with Southern California Gas Company to install a refueling station and developing a curriculum for AFV maintenance with the College of the Desert. Today the valley is home to more than 275 AFVs and 15 refueling stations.

  17. Device-Level Models Using Multi-Valley Effective Mass

    Science.gov (United States)

    Baczewski, Andrew D.; Frees, Adam; Gamble, John King; Gao, Xujiao; Jacobson, N. Tobias; Mitchell, John A.; Montaño, Inès; Muller, Richard P.; Nielsen, Erik

    2015-03-01

    Continued progress in quantum electronics depends critically on the availability of robust device-level modeling tools that capture a wide range of physics and effective mass theory (EMT) is one means of building such models. Recent developments in multi-valley EMT show quantitative agreement with more detailed atomistic tight-binding calculations of phosphorus donors in silicon (Gamble, et. al., arXiv:1408.3159). Leveraging existing PDE solvers, we are developing a framework in which this multi-valley EMT is coupled to an integrated device-level description of several experimentally active qubit technologies. Device-level simulations of quantum operations will be discussed, as well as the extraction of process matrices at this level of theory. The authors gratefully acknowledge support from the Sandia National Laboratories Truman Fellowship Program, which is funded by the Laboratory Directed Research and Development (LDRD) Program. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Security Administration under contract DE-AC04-94AL85000.

  18. POPULATION STRUCTURE AND PRODUCTION OF COPAIBA OLEORESIN BETWEEN VALLEYS AND HILLSIDES OF THE MINING AREA OFTROMBETAS RIVER - PARÁ1

    Directory of Open Access Journals (Sweden)

    Jonas Gebara

    2016-02-01

    Full Text Available ABSTRACT We aimed in this work to study natural populations of copaiba (Copaifera multijuga Hayne on the Monte Branco mountain at Porto Trombetas-PA, in order to support sustainable management and the exploitation of oleoresin from copaiba. We studied the population structure of copaiba on hillsides and valleys of the south face of Monte Branco, within Saracá Taquera National Forest, where bauxite ore was extracted in the biennium 2013-2014 by Mineração Rio do Norte (MRN. We produced a 100% forest inventory of the specie and of oleoresin extraction in order to quantify the potential production of the remaining area. The density of copaiba individuals with DBH > 30 cm was 0.33 individuals per hectare in the hillside and 0.25 individuals per hectare in the valley. Both environments presented a density of 0.28 individuals per hectare. The average copaiba oleoresin yield was 0.661±0.334 liters in the hillside and 0.765±0.280 liters in the valley. The average value of both environments together (hillside and valley was 0.714±0.218 liters. From all individuals with DBH over 30 cm, 38 (58% produced some amount of oleoresin, averaging 1.113±0.562 liters in the hillside, 1.329±0.448 liters in the valley and 1.190±0.355 liters in both environments together. The results show the need for planning the use of the surroundings of the study area in order to reach the required volume of copaiba to make feasible the sustainable management of oleoresin extraction in the region.

  19. dwindling ethiopian forests

    African Journals Online (AJOL)

    eliasn

    1999-05-26

    May 26, 1999 ... Shelter for animals: Forests are natural “habitats for many wild animals. .... nificance of forest conservation and development in Ethiopia's combat ...... of forests are not, unfortunately, analogues to traffic lights where the impact.

  20. Tenure and forest income

    DEFF Research Database (Denmark)

    Jagger, Pamela; Luckert, Martin K.; Duchelle, Amy E.

    2014-01-01

    We explore the relationship between tenure and forest income in 271 villages throughout the tropics. We find that state-owned forests generate more forest income than private and community-owned forests both per household and per hectare. We explore whether forest income varies according...... to the extent of rule enforcement, and congruence (i.e., overlap of user rights between owners and users). We find negative associations between enforcement and smallholder forest income for state-owned and community forests, and positive associations for privately owned forests. Where user rights are limited...... to formal owners we find negative associations for state-owned forests. Overlapping user rights are positively associated with forest income for community forests. Our findings suggest that policy reforms emphasizing enforcement and reducing overlapping claims to forest resources should consider possible...

  1. The River Valleys as Biodiversity Reservoirs for Land Snails in Highly Anthropic Areas – The Case of Cisnădie River (Romania

    Directory of Open Access Journals (Sweden)

    Gheoca Voichiţa

    2016-12-01

    Full Text Available This study focuses on the snail fauna of a river valley passing through two closely located settlements. Thirty six species of terrestrial gastropods were identified. Species such as Macrogastra borealis, Alinda fallax, Alinda viridana, Bulgarica vetusta, Monachoides vicinus, Drobacia banatica, are present along the river and abundant in the sampling stations downstream of Cisnădie town. The high specific diversity and the presence of typical forest species demonstrate the presence of fragments of habitat that can preserve populations of terrestrial gastropods, underlining the importance of river valleys in conservation and dispersion of these species.

  2. Chapter 16 - conservation and use of coastal wetland forests in Louisiana

    Science.gov (United States)

    Stephen P. Faulkner; Jim L. Chambers; William H. Conner; Richard F. Keim; John W. Day; Emile S. Gardiner; Melinda S. Hughes; Sammy L. King; Kenneth W. McLeod; Craig A. Miller; J. Andrew Nyman; Gary P. Shaffer

    2007-01-01

    The natural ecosystems of coastal Louisiana reflect the underlying geomorphic processes responsible for their formation. The majority of Louisiana's wetland forests are found in the lower reaches of the Mississipp Alluvial Valley and the Deltaic Plain. The sediments, water, and energy of the Mississippi River have shaped the Deltaic Plain as natural deltas have...

  3. Bottomland hardwood establishment and avian colonization of reforested sites in the Mississippi Alluvial Valley

    Science.gov (United States)

    Wilson, R.R.; Twedt, D.J.; Fredrickson, L.H.; King, S.L.; Kaminski, R.M.

    2005-01-01

    Reforestation of bottomland hardwood sites in the Mississippi Alluvial Valley has markedly increased in recent years, primarily due to financial incentive programs such as the Wetland Reserve Program, Partners for Wildlife Program, and state and private conservation programs. An avian conservation plan for the Mississippi Alluvial Valley proposes returning a substantial area of cropland to forested wetlands. Understanding how birds colonize reforested sites is important to assess the effectiveness of avian conservation. We evaluated establishment of woody species and assessed bird colonization on 89 reforested sites. These reforested sites were primarily planted with heavy-seeded oaks (Quercus spp.) and pecans (Carya illinoensis). Natural invasion of light-seeded species was expected to diversify these forests for wildlife and sustainable timber harvest. Planted tree species averaged 397 + 36 stems/ha-1, whereas naturally invading trees averaged 1675 + 241 stems/ha. However, naturally invading trees were shorter than planted trees and most natural invasion occurred <100 m from an existing forested edge. Even so, planted trees were relatively slow to develop vertical structure, especially when compared with tree species planted and managed for pulpwood production. Slow development of vertical structure resulted in grassland bird species, particularly dickcissel (Spiza americana) and red-winged blackbird (Agelaius phoeniceus), being the dominant avian colonizers for the first 7 years post-planting. High priority bird species (as defined by Partners in Flight), such as prothonotary warbler (Protonotaria citrea) and wood thrush (Hylocichla mustelina), were not frequently detected until stands were 15 years old. Canonical correspondence analysis revealed tree height had the greatest influence on the bird communities colonizing reforested sites. Because colonization by forest birds is dependent on tree height, we recommend inclusion of at least one fast-growing tree

  4. 27 CFR 9.27 - Lime Kiln Valley.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Lime Kiln Valley. 9.27... OF THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.27 Lime Kiln Valley. (a) Name. The name of the viticultural area described in this section is “Lime Kiln Valley...

  5. An example of Alaknanda valley, Garhwal Himalaya, India

    Indian Academy of Sciences (India)

    2014) have been best explained by the geometry .... flows through narrow valley confined by the steep valley slopes. ... valley (figure 3b) which opens up around Srina- ... Method. 4.1 Drainage basin and stream network. Digital Elevation Model (DEM) helps in extracting ... was processed to fill the pits or sinks, and to obtain.

  6. Indiana's Forests 2008

    Science.gov (United States)

    Christopher W. Woodall; Mark N. Webb; Barry T. Wilson; Jeff Settle; Ron J. Piva; Charles H. Perry; Dacia M. Meneguzzo; Susan J. Crocker; Brett J. Butler; Mark Hansen; Mark Hatfield; Gary Brand; Charles. Barnett

    2011-01-01

    The second full annual inventory of Indiana's forests reports more than 4.75 million acres of forest land with an average volume of more than 2,000 cubic feet per acre. Forest land is dominated by the white oak/red oak/hickory forest type, which occupies nearly a third of the total forest land area. Seventy-six percent of forest land consists of sawtimber, 16...

  7. The relationship between Anopheles gambiae density and rice cultivation in the savannah zone and forest zone of Côte d'Ivoire.

    Science.gov (United States)

    Briët, Olivier J T; Dossou-Yovo, Joel; Akodo, Elena; van de Giesen, Nick; Teuscher, Thomas M

    2003-05-01

    In 13 villages in the savannah zone and 21 villages in the forest zone of Côte d'Ivoire, the biting density of the principal malaria vector, Anopheles gambiae, was studied as a function of rice cultivation in the inland valleys in a 2-km radius around each village. In the savannah villages, during the main season cropping period, surface water on rice-cultivated and to a lesser extent on uncultivated inland valleys seems to contribute strongly to the A. gambiae population density. For the off-season cropping period (which starts after the first light rains in the savannah zone), correlations were weaker. Breeding sites other than in inland valleys may play an important role in the savannah zone. In the forest zone, however, the A. gambiae population density was strongly correlated with the surface water availability (SWA) in the rice-cultivated inland valleys, whereas the correlation with the SWA in other (uncultivated) inland valleys was weak. The requirement of sunlit breeding sites for A. gambiae might explain this difference between zones. In the forest zone, only inland valleys cleared for rice cultivation meet this requirement, whereas all other inland valleys are covered with dense vegetation. In the savannah zone, however, most undergrowth is burnt during the dry season, which permits sunlight to reach puddles resulting from the first rains.

  8. Evaluation of reforestation in the Lower Mississippi River Alluvial Valley

    Science.gov (United States)

    King, S.L.; Keeland, B.D.

    1999-01-01

    Only about 2.8 million ha of an estimated original 10 million ha of bottomland hardwood forests still exist in the Lower Mississippi River Alluvial Valley (LMAV) of the United States. The U.S. Fish and Wildlife Service, the U.S. Forest Service, and state agencies initiated reforestation efforts in the late 1980s to improve wildlife habitat. We surveyed restorationists responsible for reforestation in the LMAV to determine the magnitude of past and future efforts and to identify major limiting factors. Over the past 10 years, 77,698 ha have been reforested by the agencies represented in our survey and an additional 89,009 ha are targeted in the next 5 years. Oaks are the most commonly planted species and bare-root seedlings are the most commonly used planting stock. Problems with seedling availability may increase the diversity of plantings in the future. Reforestation in the LMAV is based upon principles of landscape ecology; however, local problems such as herbivory, drought, and flooding often limit success. Broad-scale hydrologic restoration is needed to fully restore the structural and functional attributes of these systems, but because of drastic and widespread hydrologic alterations and socioeconomic constraints, this goal is generally not realistic. Local hydrologic restoration and creation of specific habitat features needed by some wildlife and fish species warrant attention. More extensive analyses of plantings are needed to evaluate functional success. The Wetland Reserve Program is a positive development, but policies that provide additional financial incentives to landowners for reforestation efforts should be seriously considered.

  9. Development of the selection system in northern hardwood forests of the Lake States: an 80-year silviculture research legacy

    Science.gov (United States)

    Christel Kern; Gus Erdmann; Laura Kenefic; Brian Palik; Terry. Strong

    2014-01-01

    The northern hardwood research program at the Dukes Experimental Forest in Michigan and Argonne Experimental Forest in Wisconsin has been adapting to changing management and social objectives for more than 80 years. In 1926, the first northern hardwood silviculture study was established in old-growth stands at the Dukes Experimental Forest. In response to social...

  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. 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...

  12. Babesiosis in Lower Hudson Valley, New York

    Centers for Disease Control (CDC) Podcasts

    2011-05-12

    This podcast discusses a study about an increase in babesiosis in the Lower Hudson Valley of New York state. Dr. Julie Joseph, Assistant Professor of Medicine at New York Medical College, shares details of this study.  Created: 5/12/2011 by National Center for Emerging Zoonotic and Infectious Diseases (NCEZID).   Date Released: 5/23/2011.

  13. Rift Valley Fever, Mayotte, 2007–2008

    Science.gov (United States)

    Giry, Claude; Gabrie, Philippe; Tarantola, Arnaud; Pettinelli, François; Collet, Louis; D’Ortenzio, Eric; Renault, Philippe; Pierre, Vincent

    2009-01-01

    After the 2006–2007 epidemic wave of Rift Valley fever (RVF) in East Africa and its circulation in the Comoros, laboratory case-finding of RVF was conducted in Mayotte from September 2007 through May 2008. Ten recent human RVF cases were detected, which confirms the indigenous transmission of RFV virus in Mayotte. PMID:19331733

  14. SADF EARLYIRON AGE EXCAVATIONS IN THETUGELA VALLEY

    African Journals Online (AJOL)

    effect of the high flanking ridges of the Tugela. Valley. The high ... fire. Police intervention and the Bhengu superior- ity in numbers brought an end to the fights just prior to the ..... The tail and three legs of the reptile are miss- ing . . ~C£.'.':.-:".

  15. Potential hydrologic characterization wells in Amargosa Valley

    International Nuclear Information System (INIS)

    Lyles, B.; Mihevc, T.

    1994-09-01

    More than 500 domestic, agricultural, and monitoring wells were identified in the Amargosa Valley. From this list, 80 wells were identified as potential hydrologic characterization wells, in support of the US Department of Energy (DOE) Underground Test Area/Remedial Investigation and Feasibility Study (UGTA/RIFS). Previous hydrogeologic studies have shown that groundwater flow in the basin is complex and that aquifers may have little lateral continuity. Wells located more than 10 km or so from the Nevada Test Site (NTS) boundary may yield data that are difficult to correlate to sources from the NTS. Also, monitoring well locations should be chosen within the guidelines of a hydrologic conceptual model and monitoring plan. Since these do not exist at this time, recompletion recommendations will be restricted to wells relatively close (approximately 20 km) to the NTS boundary. Recompletion recommendations were made for two abandoned agricultural irrigation wells near the town of Amargosa Valley (previously Lathrop Wells), for two abandoned wildcat oil wells about 10 km southwest of Amargosa Valley, and for Test Well 5 (TW-5), about 10 km east of Amargosa Valley

  16. Geomorphological hazards in Swat valley, Pakistan

    International Nuclear Information System (INIS)

    Usman, A.

    1999-01-01

    This study attempts to describe, interpret and analyze, in depth, the varied geomorphological hazards and their impacts prevailing in the swat valley locate in the northern hilly and mountainous regions of Pakistan. The hills and mountains re zones of high geomorphological activity with rapid rates of weathering, active tectonic activities, abundant precipitation, rapid runoff and heavy sediment transport. Due to the varied topography, lithology, steep slope, erodible soil, heavy winter snowfall and intensive rainfall in the spring and summer seasons, several kinds of geomorphological hazards, such as geomorphic gravitational hazards, Fluvial hazards, Glacial hazards, Geo tectonic hazards, are occurring frequently in swat valley. Amongst them, geomorphic gravitational hazards, such as rock fall rock slide, debris slide mud flow avalanches, are major hazards in mountains and hills while fluvial hazards and sedimentation are mainly confined to the alluvial plain and lowlands of the valley. The Getechtonic hazards, on the other hand, have wide spread distribution in the valley the magnitude and occurrence of each king of hazard is thus, varied according to intensity of process and physical geographic environment. This paper discusses the type distribution and damage due to the various geomorphological hazards and their reduction treatments. The study would to be of particular importance and interest to both natural and social scientists, as well as planner, environmentalists and decision-makers for successful developmental interventions in the region. (author)

  17. Antelope Valley Community College District Education Center.

    Science.gov (United States)

    Newmyer, Joe

    An analysis is provided of a proposal to the Board of Governors of the California Community Colleges by the Antelope Valley Community College District (AVCCD) to develop an education center in Palmdale to accommodate rapid growth. First, pros and cons are discussed for the following major options: (1) increase utilization and/or expand the…

  18. Ecological Researches in the Yagnob Valley

    International Nuclear Information System (INIS)

    Razykov, Z.A.; Yunusov, M.M.; Bezzubov, N.I.; Murtazaev, Kh.; Fajzullaev, B.G.

    2002-01-01

    The article dwells on the resents of the estimation of the ecology surroundings of the Yagnob Valley. The researches included appraisal of radiation background, determination of the amount of heavy and radioactive elements in soil, bottom sedimentations, ashes in plants, water in rivers and wells. Designing on the premise of the researches implemented the ecology surrounding are estimated as propitious man's habitation. (Authors)

  19. 27 CFR 9.174 - Yadkin Valley.

    Science.gov (United States)

    2010-04-01

    ...”. (b) Approved maps. The appropriate maps for determining the boundaries of the Yadkin Valley...-Salem, N.C.; VA; Tenn. (1953, Limited Revision 1962), and, (2) Charlotte, North Carolina; South Carolina... North Carolina within Wilkes, Surry, Yadkin and portions of Stokes, Forsyth, Davidson, and Davie...

  20. 27 CFR 9.41 - Lancaster Valley.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Lancaster Valley. 9.41 Section 9.41 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... through the town of Gap and along Mine Ridge to the 76°07′30″ west longitude line in Paradise Township. (9...

  1. NNSS Soils Monitoring: Plutonium Valley (CAU 366)

    International Nuclear Information System (INIS)

    Miller, Julianne J.; Mizell, Steve A.; Nikolich, George; Campbell, Scott

    2012-01-01

    The U.S. Department of Energy (DOE) National Nuclear Security Administration (NNSA), Nevada Site Office (NSO), Environmental Restoration Soils Activity has authorized the Desert Research Institute (DRI) to conduct field assessments of potential sediment transport of contaminated soil from Corrective Action Unit (CAU) 366, Area 11 Plutonium Valley Dispersion Sites Contamination Area (CA) during precipitation runoff events.

  2. College in Paradise! (Paradise Valley Shopping Mall).

    Science.gov (United States)

    Schoolland, Lucile B.

    Rio Salado Community College (RSCC), a non-campus college within the Maricopa Community College District, offers hundreds of day, late afternoon, and evening classes at locations throughout the county. The Paradise Valley community had always participated heavily in the evening classes offered by RSCC at local high schools. In fall 1982, an effort…

  3. Temperature profiles from Salt Valley, Utah

    Science.gov (United States)

    Sass, J. H.; Lachenbruch, A. H.; Smith, E. P.

    Temperature profiles were obtained in the nine drilled wells as part of a thermal study of the Salt Valley anticline, Paradox Basin, Utha. Thermal conductivities were also measured on 10 samples judged to be representative of the rocks encountered in the deepest hole. The temperature profiles and thermal conductivities are presented, together with preliminary interpretive remarks and suggestions for additional work.

  4. Poultry Slaughter facility Zambezi Valley, Mozambique

    NARCIS (Netherlands)

    Vernooij, A.G.; Wilschut, S.

    2015-01-01

    This business plan focuses on the establishment of a slaughterhouse, one of the essential elements of a sustainable and profitable poultry meat value chain. There is a growing demand for poultry meat in the Zambezi Valley, and currently a large part of the consumed broilers comes from other parts of

  5. Business plan Hatchery Facility Zambezi Valley, Mozambique

    NARCIS (Netherlands)

    Vernooij, A.G.; Wilschut, S.

    2015-01-01

    This business plan focuses on the establishment of a hatchery, one of the essential elements of a sustainable and profitable poultry meat value chain. There is a growing demand for poultry meat in the Zambezi Valley, and currently a large part of the consumed broilers comes from other parts of the

  6. Eco-Hydrological Modelling of Stream Valleys

    DEFF Research Database (Denmark)

    Johansen, Ole

    a flow reduction in the order of 20 % in a natural spring, whereas no effect could be measured in neither short nor deep piezometers in the river valley 50 m from the spring. Problems of measuring effects of pumping are partly caused by disturbances from natural water level fluctuations. In this aspect...

  7. European Mixed Forests: definition and research perspectives

    Directory of Open Access Journals (Sweden)

    Andres Bravo-Oviedo

    2014-12-01

    Full Text Available Aim of study: We aim at (i developing a reference definition of mixed forests in order to harmonize comparative research in mixed forests and (ii review the research perspectives in mixed forests.Area of study: The definition is developed in Europe but can be tested worldwide.Material and Methods: Review of existent definitions of mixed forests based and literature review encompassing dynamics, management and economic valuation of mixed forests.Main results: A mixed forest is defined as a forest unit, excluding linear formations, where at least two tree species coexist at any developmental stage, sharing common resources (light, water, and/or soil nutrients. The presence of each of the component species is normally quantified as a proportion of the number of stems or of basal area, although volume, biomass or canopy cover as well as proportions by occupied stand area may be used for specific objectives. A variety of structures and patterns of mixtures can occur, and the interactions between the component species and their relative proportions may change over time.The research perspectives identified are (i species interactions and responses to hazards, (ii the concept of maximum density in mixed forests, (iii conversion of monocultures to mixed-species forest and (iv economic valuation of ecosystem services provided by mixed forests.Research highlights: The definition is considered a high-level one which encompasses previous attempts to define mixed forests. Current fields of research indicate that gradient studies, experimental design approaches, and model simulations are key topics providing new research opportunities.Keywords: COST Action; EuMIXFOR; mixed-species forests; admixtures of species.

  8. Montana Valley and Foothill Prairies Ecoregion: Chapter 6 in Status and trends of land change in the Western United States--1973 to 2000

    Science.gov (United States)

    Taylor, Janis L.

    2012-01-01

    The Montana Valley and Foothill Prairies Ecoregion comprises numerous intermountain valleys and low-elevation foothill prairies spread across the western half of Montana, on both sides of the Continental Divide (Omernik, 1987; U.S. Environmental Protection Agency, 1997). The ecoregion, which covers approximately 64,658 km2 (24,965 mi2), includes the Flathead Valley and the valleys surrounding Helena, Missoula, Bozeman, Billings, Anaconda, Dillon, and Lewistown (fig. 1). These valleys are generally characterized by shortgrass prairie vegetation and are flanked by forested mountains (Woods and others, 1999); thus, the valleys’ biotas with regards to fish and insects are comparable. In many cases, the valleys are conduits for some of the largest rivers in the state, including Clark Fork and the Missouri, Jefferson, Madison, Flathead, Yellowstone, Gallatin, Smith, Big Hole, Bitterroot, and Blackfoot Rivers (fig. 2). The Montana Valley and Foothill Prairies Ecoregion also includes the “Rocky Mountain front,” an area of prairies along the eastern slope of the northern Rocky Mountains. Principal land uses within the ecoregion include farming, grazing, and mining. The valleys serve as major transportation and utility corridors and also contain the majority of Montana’s human population. The Montana Valley and Foothill Prairies Ecoregion extends into 17 mostly rural counties throughout western Montana. Only three of the counties—Carbon, Yellowstone, and Missoula—are part of a metropolitan statistical area with contiguous built-up areas tied to an employment center. Nearly two-thirds of Montana residents live in nonmetropolitan counties (Albrecht, 2008). Ten of the counties within the ecoregion had population growth rates greater than national averages (9–13 percent) between 1970 and 2000 (table 1). Ravalli and Gallatin Counties had the highest growth rates. Population growth was largely due to amenity-related inmigration and an economy dependent on tourism

  9. Quantum Hall Valley Nematics: From Field Theories to Microscopic Models

    Science.gov (United States)

    Parameswaran, Siddharth

    The interplay between quantum Hall ordering and spontaneously broken ``internal'' symmetries in two-dimensional electron systems with spin or pseudospin degrees of freedom gives rise to a variety of interesting phenomena, including novel phases, phase transitions, and topological excitations. I will discuss a theory of broken-symmetry quantum Hall states, applicable to a class of multivalley systems, where the symmetry at issue is a point-group element that combines a spatial rotation with a permutation of valley indices. I will explore its ramifications for the phase diagram of a variety of experimental systems, such as AlAs and Si quantum wells and the surface states of bismuth. I will also discuss unconventional transport phenomena in these phases in the presence of quenched randomness, and the possible mechanisms of selection between degenerate broken-symmetry phases in clean systems. I acknowledge support from NSF DMR-1455366.

  10. The geochemistry of groundwater resources in the Jordan Valley: The impact of the Rift Valley brines

    Science.gov (United States)

    Farber, E.; Vengosh, A.; Gavrieli, I.; Marie, Amarisa; Bullen, T.D.; Mayer, B.; Polak, A.; Shavit, U.

    2007-01-01

    The chemical composition of groundwater in the Jordan Valley, along the section between the Sea of Galilee and the Dead Sea, is investigated in order to evaluate the origin of the groundwater resources and, in particular, to elucidate the role of deep brines on the chemical composition of the regional groundwater resources in the Jordan Valley. Samples were collected from shallow groundwater in research boreholes on two sites in the northern and southern parts of the Jordan Valley, adjacent to the Jordan River. Data is also compiled from previous published studies. Geochemical data (e.g., Br/Cl, Na/Cl and SO4/Cl ratios) and B, O, Sr and S isotopic compositions are used to define groundwater groups, to map their distribution in the Jordan valley, and to evaluate their origin. The combined geochemical tools enabled the delineation of three major sources of solutes that differentially affect the quality of groundwater in the Jordan Valley: (1) flow and mixing with hypersaline brines with high Br/Cl (>2 ?? 10-3) and low Na/Cl (shallow saline groundwaters influenced by brine mixing exhibit a north-south variation in their Br/Cl and Na/Cl ratios. This chemical trend was observed also in hypersaline brines in the Jordan valley, which suggests a local mixing process between the water bodies. ?? 2007 Elsevier Ltd. All rights reserved.

  11. Impacts on the Yukon and the Mackenzie Valley

    International Nuclear Information System (INIS)

    Parker, N.; Cowan, C.

    1993-01-01

    Climate models predicting the effects of global warming due to the greenhouse effect give rough estimates of the sign and size of expected changes in temperature and precipitation. However, these models do not show what to expect from a warmer regional climate. One approach to resolve this issue is to use climate information from past years and find a year whose climate is close to what the models say will exist in the future. This approach is used to gain some understanding into what climatic warming may mean to the Yukon and Mackenzie Valley areas of Arctic Canada. The summer of 1989, one of the warmest summers on record, is studied to examine the effects of climate warming on agriculture, stream flow, glacial melting, permafrost degradation, and forest fires. Under a climate scenario in which the 1989 summer became the average, agricultural land classification would increase although moisture and soil suitability would still limit many crops. Lower-level glaciers would likely continue their rapid melt while some higher-level glaciers and snowfields might expand due to increased moisture, especially during winter. 10 refs., 5 figs., 4 tabs

  12. European mixed forests

    DEFF Research Database (Denmark)

    Bravo-Oviedo, Andres; Pretzsch, Hans; Ammer, Christian

    2014-01-01

    Aim of study: We aim at (i) developing a reference definition of mixed forests in order to harmonize comparative research in mixed forests and (ii) review the research perspectives in mixed forests. Area of study: The definition is developed in Europe but can be tested worldwide. Material...... and Methods: Review of existent definitions of mixed forests based and literature review encompassing dynamics, management and economic valuation of mixed forests. Main results: A mixed forest is defined as a forest unit, excluding linear formations, where at least two tree species coexist at any...... density in mixed forests, (iii) conversion of monocultures to mixed-species forest and (iv) economic valuation of ecosystem services provided by mixed forests. Research highlights: The definition is considered a high-level one which encompasses previous attempts to define mixed forests. Current fields...

  13. Chilean central valley beekeeping as socially inclusive conservation practice in a social water scarcity context

    Directory of Open Access Journals (Sweden)

    Felipe Eduardo Trujillo Bilbao

    2017-07-01

    Full Text Available Through an ethnographic approach that complements conversations, tours and surveys of productive characterization is that the present study aims to approach the domestic beekeeping in the valley of Colliguay, Quilpué, fifth region of Chile. This is an activity that emerges as a result of deep transformations detonated by the neoliberalization of nature in general and water in particular. That is why it seeks to contextualize the situation of water scarcity that displaced livestock and put in place the bees. All of this through a political ecology lens. It is discussed how to achieve an anthropological reading of the ecological scenarios that denaturalize metabolic fractures in an area with a threatened presence of native forest. It is discovered that the outsider is the material and symbolic responsible of an increase in water stress and a key element in the social relations of confrontation of the valley. It is then related how bees have diverted the attention of their human counterparts to the affection and care of the forest that allows them to live, thus reinforcing the idea of a socially inclusive conservation.

  14. Palms and Palm Communities in the Upper Ucayali River Valley - a Little-Known Region in the Amazon Basin

    DEFF Research Database (Denmark)

    Balslev, Henrik; Eiserhardt, Wolf L.; Kristiansen, Thea

    2010-01-01

    The Amazon region and its palms are inseparable. Palms make up such an important part of the rain forest ecosystem that it is impossible to imagine the Amazon basin without them. Palms are visible in the canopy and often fill up the forest understory. Palms – because of their edible fruits...... – are cornerstone species for the survival of many animals, and palms contribute substantially to forest inventories in which they are often among the ten most important families. Still, the palms and palm communities of some parts of the Amazon basin remain poorly studied and little known. We travelled to a little......-explored corner of the western Amazon basin, the upper Ucayali river valley. There, we encountered 56 different palms, 18 of which had not been registered for the region previously, and 21 of them were found 150–400 km beyond their previously known limits....

  15. 27 CFR 9.58 - Carmel Valley.

    Science.gov (United States)

    2010-04-01

    ... the southwest corner of Section 36. (5) From this point, the boundary follows the Los Padres National..., where the section line rejoins the Los Padres National Forest boundary. (7) The boundary follows the Los Padres National Forest boundary to the north-south section line dividing Section 11 from Section 12 in...

  16. Forest tenure and sustainable forest management

    Science.gov (United States)

    J.P. Siry; K. McGinley; F.W. Cubbage; P. Bettinger

    2015-01-01

    We reviewed the principles and key literature related to forest tenure and sustainable forest management, and then examined the status of sustainable forestry and land ownership at the aggregate national level for major forested countries. The institutional design principles suggested by Ostrom are well accepted for applications to public, communal, and private lands....

  17. A valley-filtering switch based on strained graphene.

    Science.gov (United States)

    Zhai, Feng; Ma, Yanling; Zhang, Ying-Tao

    2011-09-28

    We investigate valley-dependent transport through a graphene sheet modulated by both the substrate strain and the fringe field of two parallel ferromagnetic metal (FM) stripes. When the magnetizations of the two FM stripes are switched from the parallel to the antiparallel alignment, the total conductance, valley polarization and valley conductance excess change greatly over a wide range of Fermi energy, which results from the dependence of the valley-related transmission suppression on the polarity configuration of inhomogeneous magnetic fields. Thus the proposed structure exhibits the significant features of a valley-filtering switch and a magnetoresistance device.

  18. A valley-filtering switch based on strained graphene

    International Nuclear Information System (INIS)

    Zhai Feng; Ma Yanling; Zhang Yingtao

    2011-01-01

    We investigate valley-dependent transport through a graphene sheet modulated by both the substrate strain and the fringe field of two parallel ferromagnetic metal (FM) stripes. When the magnetizations of the two FM stripes are switched from the parallel to the antiparallel alignment, the total conductance, valley polarization and valley conductance excess change greatly over a wide range of Fermi energy, which results from the dependence of the valley-related transmission suppression on the polarity configuration of inhomogeneous magnetic fields. Thus the proposed structure exhibits the significant features of a valley-filtering switch and a magnetoresistance device. (paper)

  19. Hidden Valley Searches at ATLAS

    CERN Document Server

    Ventura, D; The ATLAS collaboration

    2011-01-01

    A number of extensions of the Standard Model result in neutral and weakly-coupled particles that decay to multi hadrons or multi leptons with macroscopic decay lengths. These particles with decay paths that can be comparable with ATLAS detector dimensions represent, from an experimental point of view, a challenge both for the trigger and for the reconstruction capabilities of the ATLAS detector. We will present a set of signature driven triggers for the ATLAS detector that target such displaced decays and evaluate their performances for some benchmark models.

  20. Status and management of watersheds in the Upper Pokhara Valley, Nepal

    Science.gov (United States)

    Thapa, Gopal B.; Weber, Karl E.

    1995-07-01

    Contributing to the debate on the causes of Himalayan environmental degradation, the status and management of four watersheds in the Upper Pokhara Valley were studied using information available from land use analysis, household surveys conducted in 1989 and 1992, deliberations held with villagers, and field observations. Accordingly, areas under forests and grazing lands were found being depleted at relatively high rates between 1957 and 1978 due mainly to the government policy of increasing national revenue by expansion of agricultural lands, nationalization of forests, steadily growing population, and dwindling household economy. Despite the steady growth of population, this process had remarkably slackened since 1978, owing primarily to remaining forests being located in very, steep slopes and implementation of the community forestry program. Forests with relatively sparase tree density, however, and grazing lands in the vicinity of settlements have been undergoing degradation due to fuelwood and fodder collection and livestock grazing. In many instances, this is aggravated by weak resource management institutions. Being particularly aware of the economic implication of land degradation, farmers have adopted assorted land management practices. Still a substantial proportion of bari lands in the hill slopes is vulnerable to accelerating degradation, as the arable cropping system is being practiced there as well. The perpetuation of the local subsistence economy is certain to lead, to a further deterioration of the socioeconomic and environmental conditions of watersheds. To facilitate environmental conservation and ecorestructuring for sustainable development, a broad watershed management strategy is outlined with focus on alleviating pressure on natural resources.

  1. Space and habitat use by black bears in the Elwha valley prior to dam removal

    Science.gov (United States)

    Sager-Fradkin, K.A.; Jenkins, K.J.; Happe, P.J.; Beecham, J.J.; Wright, R.G.; Hoffman, R.A.

    2008-01-01

    Dam removal and subsequent restoration of salmon to the Elwha River is expected to cause a shift in nutrient dynamics within the watershed. To document how this influx of nutrients and energy may affect black bear (Ursus americanus) ecology, we used radio-telemetry to record movements of 11 male and two female black bears in the Elwha Valley from 2002-06. Our objective was to collect baseline data on bear movements prior to dam removal. We calculated annual home ranges, described seasonal timing of den entry and emergence, and described seasonal patterns of distribution and habitat use. Adaptive kernel home ranges were larger formales (mean = 151.1 km2, SE = 21.4) than females (mean = 38.8 km2, SE = 13.0). Males ranged widely and frequently left the watershed during late summer. Further, they exhibited predictable and synchronous patterns of elevation change throughout each year. Bears entered their winter dens between 8 October and 15 December and emerged from dens between 10 March and 9 May. Male bears used low-elevation conifer and hardwood forests along the Elwha floodplain during spring, mid- to high-elevation forests and meadows during early summer, high-elevation forests, meadows and shrubs during late summer, and mid-elevation forests, shrubs and meadows during fall. Data acquired during this study provide important baseline information for comparison after dam removal, when bears may alter their late summer and fall movement and denning patterns to take advantage of energy-rich spawning salmon.

  2. [The impact of population growth on Tamba Kosi, a Himalayan valley in Nepal].

    Science.gov (United States)

    Verliat, S

    1994-01-01

    Two several-month-long stays in the isolated Tamba Kosi valley in Nepal in 1983 and 1986 allowed an assessment of the importance of changes in rural societies. In about 50 years, the oldest inhabitants of some villages have seen the number of houses quadruple. In the absence of reliable statistical data, the inhabitants say that the Tamba Kosi valley population has doubled in the last 25 years. This population growth exacerbates the multiethnic fight for good land (i.e., ground of modest slope, hot, and humid). Many people have emigrated, which has somewhat eased problems relative to population growth. Soil degradation, which is becoming more and more acute, drives the inhabitants to cut down trees and clear the land for cultivation of new plots. These new plots are running up against steep slopes and high altitude. Most families have barely two hectares, which must suffice to feed 5-6 people on average. This fuels intensification of agricultural production, resulting in low efficacy. Livestock mutilate forests with their hooves and teeth. The marked increase in the variety of livestock accelerates this destruction. Three types of building materials are used in this high valley: thatch, shingles (fir tree), and bamboo matting. The disappearance of wild grasses used to make thatch roofs and people moving to higher and higher altitudes resulted in use of shingles to make roofs. Buildings made of shingles, which demanded changes in construction techniques, changed the conception of homes. They became the preferred building type, which increased the demand for fir trees and deforestation. This lead to a demand for roofing material made of bamboo matting and another change in construction techniques. The retreat of the forest and disappearance of the most wanted plant species are the most spectacular impacts of population growth. This environmental degradation exacerbates erosion at all bioclimatic altitudes.

  3. Atmospheric dispersion experiments over complex terrain in a spanish valley site (Guardo-90)

    International Nuclear Information System (INIS)

    Ibarra, J.I.

    1991-01-01

    An intensive field experimental campaign was conducted in Spain to quantify atmospheric diffusion within a deep, steep-walled valley in rough, mountainous terrain. The program has been sponsored by the spanish companies of electricity and is intended to validate existing plume models and to provide the scientific basis for future model development. The atmospheric dispersion and transport processes in a 40x40 km domain were studied in order to evaluate SO 2 and SF 6 releases from an existing 185 m chimney and ground level sources in a complex terrain valley site. Emphasis was placed on the local mesoscale flows and light wind stable conditions. Although the measuring program was intensified during daytime for dual tracking of SO 2 /SF 6 from an elevated source, nighttime experiments were conducted for mountain-valley flows characterization. Two principle objectives were pursued: impaction of plumes upon elevated terrain, and diffusion of gases within the valley versus diffusion over flat, open terrain. Artificial smoke flows visualizations provided qualitative information: quantitative diffusion measurements were obtained using sulfur hexafluoride gas with analysis by highly sensitive electron capture gas chromatographs systems. Fourteen 2 hours gaseous tracer releases were conducted

  4. Restoring forests

    DEFF Research Database (Denmark)

    Jacobs, Douglass F.; Oliet, Juan A.; Aronson, James

    2015-01-01

    of land requiring restoration implies the need for spatial prioritization of restoration efforts according to cost-benefit analyses that include ecological risks. To design resistant and resilient ecosystems that can adapt to emerging circumstances, an adaptive management approach is needed. Global change......, in particular, imparts a high degree of uncertainty about the future ecological and societal conditions of forest ecosystems to be restored, as well as their desired goods and services. We must also reconsider the suite of species incorporated into restoration with the aim of moving toward more stress resistant...... and competitive combinations in the longer term. Non-native species may serve an important role under some circumstances, e.g., to facilitate reintroduction of native species. Propagation and field establishment techniques must promote survival through seedling stress resistance and site preparation. An improved...

  5. Sustaining Urban Forests

    Science.gov (United States)

    John F. Dwyer; David J. Nowak

    2003-01-01

    The significance of the urban forest resource and the powerful forces for change in the urban environment make sustainability a critical issue in urban forest management. The diversity, connectedness, and dynamics of the urban forest establish the context for management that will determine the sustainability of forest structure, health, functions, and benefits. A...

  6. North Dakota's forests 2005

    Science.gov (United States)

    David E. Haugen; Michael Kangas; Susan J. Crocker; Charles H. Perry; Christopher W. Woodall; Brett J. Butler; Barry T. Wilson; Dan J. Kaisershot

    2009-01-01

    The first completed annual inventory of North Dakota's forests reports estimates of more than 724,000 acres of forest land. Information about forest attributes and forest health is presented along with information on agents of change including changing land use patterns and the introduction of nonnative plants, insects, and disease.

  7. Forest Health Detectives

    Science.gov (United States)

    Bal, Tara L.

    2014-01-01

    "Forest health" is an important concept often not covered in tree, forest, insect, or fungal ecology and biology. With minimal, inexpensive equipment, students can investigate and conduct their own forest health survey to assess the percentage of trees with natural or artificial wounds or stress. Insects and diseases in the forest are…

  8. Wisconsin's forests, 2004

    Science.gov (United States)

    Charles H. (Hobie) Perry; Vern A. Everson; Ian K. Brown; Jane Cummings-Carlson; Sally E. Dahir; Edward A. Jepsen; Joe Kovach; Michael D. Labissoniere; Terry R. Mace; Eunice A. Padley; Richard B. Rideout; Brett J. Butler; Susan J. Crocker; Greg C. Liknes; Randall S. Morin; Mark D. Nelson; Barry T. (Ty) Wilson; Christopher W. Woodall

    2008-01-01

    The first full, annualized inventory of Wisconsin's forests was completed in 2004 after 6,478 forested plots were visited. There are more than 16.0 million acres of forest land in the Wisconsin, nearly half of the State's land area; 15.8 million acres meet the definition of timberland. The total area of both forest land and timberland continues an upward...

  9. Managing Sierra Nevada forests

    Science.gov (United States)

    Malcolm North

    2012-01-01

    There has been widespread interest in applying new forest practices based on concepts presented in U.S. Forest Service General Technical Report PSW-GTR-220, "An Ecosystem Management Strategy for Sierran Mixed-Conifer Forests." This collection of papers (PSW-GTR-237) summarizes the state of the science in some topics relevant to this forest management approach...

  10. Hidden Valley Search at ATLAS

    CERN Document Server

    Verducci, M; The ATLAS collaboration

    2011-01-01

    A number of extensions of the Standard Model result in neutral and weakly-coupled particles that decay to multi hadrons or multi leptons with macroscopic decay lengths. These particles with decay paths that can be comparable with ATLAS detector dimensions represent, from an experimental point of view, a challenge both for the trigger and for the reconstruction capabilities of the ATLAS detector. We will present a set of signature driven triggers for the ATLAS detector that target such displaced decays and evaluate their performances for some benchmark models. and describe analysis strategies and limits on the production of such long-lived particles that can be achieved with the first 100 pb-1.

  11. Wild European Apple (Malus sylvestris (L.) Mill.) Population Dynamics: Insight from Genetics and Ecology in the Rhine Valley. Priorities for a Future Conservation Programme

    Science.gov (United States)

    Schnitzler, Annik; Arnold, Claire; Cornille, Amandine; Bachmann, Olivier; Schnitzler, Christophe

    2014-01-01

    The increasing fragmentation of forest habitats and the omnipresence of cultivars potentially threaten the genetic integrity of the European wild apple (Malus sylvestris (L.) Mill). However, the conservation status of this species remains unclear in Europe, other than in Belgium and the Czech Republic, where it has been declared an endangered species. The population density of M. sylvestris is higher in the forests of the upper Rhine Valley (France) than in most European forests, with an unbalanced age-structure, an overrepresentation of adults and a tendency to clump. We characterize here the ecology, age-structure and genetic diversity of wild apple populations in the Rhine Valley. We use these data to highlight links to the history of this species and to propose guidelines for future conservation strategies. In total, 255 individual wild apple trees from six forest stands (five floodplain forests and one forest growing in drier conditions) were analysed in the field, collected and genotyped on the basis of data for 15 microsatellite markers. Genetic analyses showed no escaped cultivars and few hybrids with the cultivated apple. Excluding the hybrids, the genetically “pure” populations displayed high levels of genetic diversity and a weak population structure. Age-structure and ecology studies of wild apple populations identified four categories that were not randomly distributed across the forests, reflecting the history of the Rhine forest over the last century. The Rhine wild apple populations, with their ecological strategies, high genetic diversity, and weak traces of crop-to-wild gene flow associated with the history of these floodplain forests, constitute candidate populations for inclusion in future conservation programmes for European wild apple. PMID:24827575

  12. Wild European apple (Malus sylvestris (L.) Mill.) population dynamics: insight from genetics and ecology in the Rhine Valley. Priorities for a future conservation programme.

    Science.gov (United States)

    Schnitzler, Annik; Arnold, Claire; Cornille, Amandine; Bachmann, Olivier; Schnitzler, Christophe

    2014-01-01

    The increasing fragmentation of forest habitats and the omnipresence of cultivars potentially threaten the genetic integrity of the European wild apple (Malus sylvestris (L.) Mill). However, the conservation status of this species remains unclear in Europe, other than in Belgium and the Czech Republic, where it has been declared an endangered species. The population density of M. sylvestris is higher in the forests of the upper Rhine Valley (France) than in most European forests, with an unbalanced age-structure, an overrepresentation of adults and a tendency to clump. We characterize here the ecology, age-structure and genetic diversity of wild apple populations in the Rhine Valley. We use these data to highlight links to the history of this species and to propose guidelines for future conservation strategies. In total, 255 individual wild apple trees from six forest stands (five floodplain forests and one forest growing in drier conditions) were analysed in the field, collected and genotyped on the basis of data for 15 microsatellite markers. Genetic analyses showed no escaped cultivars and few hybrids with the cultivated apple. Excluding the hybrids, the genetically "pure" populations displayed high levels of genetic diversity and a weak population structure. Age-structure and ecology studies of wild apple populations identified four categories that were not randomly distributed across the forests, reflecting the history of the Rhine forest over the last century. The Rhine wild apple populations, with their ecological strategies, high genetic diversity, and weak traces of crop-to-wild gene flow associated with the history of these floodplain forests, constitute candidate populations for inclusion in future conservation programmes for European wild apple.

  13. Can aspen persist in conifer dominated forests?

    Science.gov (United States)

    Douglas H. Page; John D. Shaw

    2016-01-01

    In 1998 we measured a large, old aspen in a mixed spruce-fir-aspen forest on the Utah State University T.W. Daniel Experimental Forest in northern Utah. The tree was 297 years old - about the same age as the oldest spruce in the stand. A search of the forestry literature revealed that the oldest published age for an aspen came from a tree in the Sierra Nevada Range in...

  14. Landscape Mapping and Tree Diversity Assessment of Pangi Valley: A Remote Tribal Area of Himachal Pradesh in Western Himalaya, India

    Directory of Open Access Journals (Sweden)

    Amit KUMAR

    2013-12-01

    Full Text Available Pangi valley in Chamba district of Himachal Pradesh is one of the remote tribal areas in Indian western Himalaya. The plant resources in its landscapes are flourishing under least anthropogenic conditions. For social upliftment of the tribals in this area, a number of developmental activities are being implemented by the government. A study was conducted for mapping of its landuse/landcover using satellite remote sensing to identify major forested landscapes in the region. It was followed by a detailed random stratified sampling of the forested landscapes for phytosociological estimation of its tree species. The 21.97 % of study area was estimated under forests followed by Scrublands and Grassy meadows (18.24 %. Majority of area (54.05 % was Snow and Scree slopes. Among the forests, maximum area was occupied by Mixed Broad Leaved Forest LSE type (36.08% followed by Cedrus deodara (26.94% and Betula utilis (18.07% forest LSE types. These species, owing to immense medicinal properties and value for their economic utilization, feature in threatened and endangered category list of plants. It is, therefore, recommended that the developmental activities may be implemented in scientific way, which may not pose threat to bioresources in this region.

  15. Groundwater quality in the Antelope Valley, California

    Science.gov (United States)

    Dawson, Barbara J. Milby; Belitz, Kenneth

    2012-01-01

    Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State’s groundwater quality and increases public access to groundwater-quality information. Antelope Valley is one of the study areas being evaluated. The Antelope study area is approximately 1,600 square miles (4,144 square kilometers) and includes the Antelope Valley groundwater basin (California Department of Water Resources, 2003). Antelope Valley has an arid climate and is part of the Mojave Desert. Average annual rainfall is about 6 inches (15 centimeters). The study area has internal drainage, with runoff from the surrounding mountains draining towards dry lakebeds in the lower parts of the valley. Land use in the study area is approximately 68 percent (%) natural (mostly shrubland and grassland), 24% agricultural, and 8% urban. The primary crops are pasture and hay. The largest urban areas are the cities of Palmdale and Lancaster (2010 populations of 152,000 and 156,000, respectively). Groundwater in this basin is used for public and domestic water supply and for irrigation. The main water-bearing units are gravel, sand, silt, and clay derived from surrounding mountains. The primary aquifers in Antelope Valley are defined as those parts of the aquifers corresponding to the perforated intervals of wells listed in the California Department of Public Health database. Public-supply wells in Antelope Valley are completed to depths between 360 and 700 feet (110 to 213 meters), consist of solid casing from the land surface to a depth of 180 to 350 feet (55 to 107 meters), and are screened or perforated below the solid casing. Recharge to the groundwater system is primarily runoff from the surrounding mountains, and by direct infiltration of irrigation and sewer and septic

  16. Groundwater quality in the Owens Valley, California

    Science.gov (United States)

    Dawson, Barbara J. Milby; Belitz, Kenneth

    2012-01-01

    Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State’s groundwater quality and increases public access to groundwater-quality information. Owens Valley is one of the study areas being evaluated. The Owens study area is approximately 1,030 square miles (2,668 square kilometers) and includes the Owens Valley groundwater basin (California Department of Water Resources, 2003). Owens Valley has a semiarid to arid climate, with average annual rainfall of about 6 inches (15 centimeters). The study area has internal drainage, with runoff primarily from the Sierra Nevada draining east to the Owens River, which flows south to Owens Lake dry lakebed at the southern end of the valley. Beginning in the early 1900s, the City of Los Angeles began diverting the flow of the Owens River to the Los Angeles Aqueduct, resulting in the evaporation of Owens Lake and the formation of the current Owens Lake dry lakebed. Land use in the study area is approximately 94 percent (%) natural, 5% agricultural, and 1% urban. The primary natural land cover is shrubland. The largest urban area is the city of Bishop (2010 population of 4,000). Groundwater in this basin is used for public and domestic water supply and for irrigation. The main water-bearing units are gravel, sand, silt, and clay derived from surrounding mountains. Recharge to the groundwater system is primarily runoff from the Sierra Nevada, and by direct infiltration of irrigation. The primary sources of discharge are pumping wells, evapotranspiration, and underflow to the Owens Lake dry lakebed. The primary aquifers in Owens Valley are defined as those parts of the aquifers corresponding to the perforated intervals of wells listed in the California Department of Public Health database

  17. Microscopic Identification of Prokaryotes in Modern and Ancient Halite, Saline Valley and Death Valley, California

    Science.gov (United States)

    Schubert, Brian A.; Lowenstein, Tim K.; Timofeeff, Michael N.

    2009-06-01

    Primary fluid inclusions in halite crystallized in Saline Valley, California, in 1980, 2004-2005, and 2007, contain rod- and coccoid-shaped microparticles the same size and morphology as archaea and bacteria living in modern brines. Primary fluid inclusions from a well-dated (0-100,000 years), 90 m long salt core from Badwater Basin, Death Valley, California, also contain microparticles, here interpreted as halophilic and halotolerant prokaryotes. Prokaryotes are distinguished from crystals on the basis of morphology, optical properties (birefringence), and uniformity of size. Electron micrographs of microparticles from filtered modern brine (Saline Valley), dissolved modern halite crystals (Saline Valley), and dissolved ancient halite crystals (Death Valley) support in situ microscopic observations that prokaryotes are present in fluid inclusions in ancient halite. In the Death Valley salt core, prokaryotes in fluid inclusions occur almost exclusively in halite precipitated in perennial saline lakes 10,000 to 35,000 years ago. This suggests that trapping and preservation of prokaryotes in fluid inclusions is influenced by the surface environment in which the halite originally precipitated. In all cases, prokaryotes in fluid inclusions in halite from the Death Valley salt core are miniaturized (<1 μm diameter cocci, <2.5 μm long, very rare rod shapes), which supports interpretations that the prokaryotes are indigenous to the halite and starvation survival may be the normal response of some prokaryotes to entrapment in fluid inclusions for millennia. These results reinforce the view that fluid inclusions in halite and possibly other evaporites are important repositories of microbial life and should be carefully examined in the search for ancient microorganisms on Earth, Mars, and elsewhere in the Solar System.

  18. West Virginia Forests 2013

    Science.gov (United States)

    Randall S. Morin; Gregory W. Cook; Charles J. Barnett; Brett J. Butler; Susan J. Crocker; Mark A. Hatfield; Cassandra M. Kurtz; Tonya W. Lister; William G. Luppold; William H. McWilliams; Patrick D. Miles; Mark D. Nelson; Charles H. (Hobie) Perry; Ronald J. Piva; James E. Smith; Jim Westfall; Richard H. Widmann; Christopher W. Woodall

    2016-01-01

    The annual inventory of West Virginia's forests, completed in 2013, covers nearly 12.2 million acres of forest land with an average volume of more than 2,300 cubic feet per acre. This report is based data collected from 2,808 plots located across the State. Forest land is dominated by the oak/hickory forest-type group, which occupies 74 percent of total forest...

  19. Illinois' Forests 2010

    Science.gov (United States)

    Susan J. Crocker; Mark D. Nelson; Charles J. Barnett; Brett J. Butler; Grant M. Domke; Mark H. Hansen; Mark A. Hatfield; Tonya W. Lister; Dacia M. Meneguzzo; Ronald J. Piva; Barry T. Wilson; Christopher W. Woodall

    2013-01-01

    The second full annual inventory of Illinois' forests, completed in 2010, reports more than 4.8 million acres of forest land and 97 tree species. Forest land is dominated by oak/hickory and elm/ash/cottonwood forest-type groups, which occupy 93 percent of total forest land area. The volume of growing stock on timberland totals 7.2 billion cubic feet. The average...

  20. Nebraska's Forests 2010

    Science.gov (United States)

    Dacia M Meneguzzo; Susan J. Crocker; Mark D. Nelson; Charles J. Barnett; Brett J. Butler; Grant M. Domke; Mark H. Hansen; Mark A. Hatfield; Greg C. Liknes; Andrew J. Lister; Tonya W. Lister; Ronald J. Piva; Barry T. (Ty) Wilson; Christopher W. Woodall

    2012-01-01

    The second full annual inventory of Nebraska's forests reports more than 1.5 million acres of forest land and 39 tree species. Forest land is dominated by the elm/ash/cottonwood and oak/hickory forest types, which occupy nearly half of the total forest land area. The volume of growing stock on timberland currently totals 1.1 billion cubic feet. The average annual...

  1. New Jersey's forests, 2008

    Science.gov (United States)

    Susan J. Crocker; Mark D. Nelson; Charles J. Barnett; Gary J. Brand; Brett J. Butler; Grant M. Domke; Mark H. Hansen; Mark A. Hatfield; Tonya W. Lister; Dacia M. Meneguzzo; Charles H. Perry; Ronald J. Piva; Barry T. Wilson; Christopher W. Woodall; Bill. Zipse

    2011-01-01

    The first full annual inventory of New Jersey's forests reports more than 2.0 million acres of forest land and 83 tree species. Forest land is dominated by oak-hickory forest types in the north and pitch pine forest types in the south. The volume of growing stock on timberland has been rising since 1956 and currently totals 3.4 billion cubic feet. The average...

  2. Forest Grammar(Ⅰ)

    Institute of Scientific and Technical Information of China (English)

    张松懋

    1994-01-01

    Forest grammar,a new type of high-dimensional grammar,is proposed in this paper,of which both the left and the right parts of every production are concatenations of tree structures.A classification of forest grammar is studied,especially,a subclass of the forest grammar,i.e.the context-sensitive forest grammar,and one of its subclasses is defined,called the weak precedence forest grammar.

  3. New Jersey Forests 2013

    Science.gov (United States)

    Susan J. Crocker; Charles J. Barnett; Brett J. Butler; Mark A. Hatfield; Cassandra M. Kurtz; Tonya W. Lister; Dacia M. Meneguzzo; Patrick D. Miles; Randall S. Morin; Mark D. Nelson; Ronald J. Piva; Rachel Riemann; James E. Smith; Christopher W. Woodall; William. Zipse

    2017-01-01

    The second full annual inventory of New Jersey’s forests reports more than 2.0 million acres of forest land and 77 tree species. Forest land is dominated by oak/hickory forest types in the north and pitch pine forest types in the south. The volume of growing stock on timberland has been rising since 1956 and currently totals 3.3 billion cubic feet. Average annual net...

  4. Michigan's Forests 2009

    Science.gov (United States)

    Scott A. Pugh; Lawrence D. Pedersen; Douglas C. Heym; Ronald J. Piva; Christopher W. Woodall; Charles J. Barnett; Cassandra M. Kurtz; W. Keith. Moser

    2012-01-01

    The seventh inventory of Michigan's forests, completed in 2009, describes more than 19.9 million acres of forest land. The data in this report are based on visits to 7,516 forested plots from 2005 to 2009. Timberland accounts for 97 percent of this forest land, and 62 percent is privately owned. The sugar maple/beech/yellow birch forest type accounts for 18...

  5. Michigan's forests 2004

    Science.gov (United States)

    Scott A. Pugh; Mark H. Hansen; Lawrence D. Pedersen; Douglas C. Heym; Brett J. Butler; Susan J. Crocker; Dacia Meneguzzo; Charles H. Perry; David E. Haugen; Christopher Woodall; Ed Jepsen

    2009-01-01

    The first annual inventory of Michigan's forests, completed in 2004, covers more than 19.3 million acres of forest land. The data in this report are based on visits to 10,355 forested plots from 2000 to 2004. In addition to detailed information on forest attributes, this report includes data on forest health, biomass, land-use change, and timber-product outputs....

  6. Monitoring air quality with lichens: A comparison between mapping in forest sites and in open areas

    International Nuclear Information System (INIS)

    Policnik, Helena; Simoncic, Primoz; Batic, Franc

    2008-01-01

    Four different methods of epiphytic lichen mapping were used for the assessment of air quality in the region under the influence of the Sostanj Thermal Power Plant (Salek Valley, Slovenia). Three methods were based on the presence of different lichen species (VDI, EU and ICP-Forest), the fourth on a frequency and coverage assessment of different growth forms of epiphytic lichens, e.g. crustose, foliose and fruticose (SI). A comparison of the results from the assessment of air quality between forest sites (ICP-Forest, SI) and open areas (VDI, EU and SI), obtained by the different methods of epiphytic lichen mapping, is presented in the contribution. Data showed that lichen species richness is worse in forest sites in comparison with open areas. From the data obtained it can be concluded that epiphytic lichen mapping in open areas is a better method for the assessment of air pollution in a given area than mapping in forest sites. The species-based methods in open areas are more powerful and useful for air quality assessment in polluted research areas than the SI and ICP-Forest methods. - The mapping of epiphytic lichens in open areas is more suitable for air quality assessment than mapping in forest sites in the Salek Valley, Slovenia

  7. Prevalence and distribution of pox-like lesions, avian malaria, and mosquito vectors in Kipahulu valley, Haleakala National Park, Hawai'i, USA

    Science.gov (United States)

    Aruch, Samuel; Atkinson, Carter T.; Savage, Amy F.; LaPointe, Dennis

    2007-01-01

    We determined prevalence and altitudinal distribution of introduced avian malarial infections (Plasmodium relictum) and pox-like lesions (Avipoxvirus) in forest birds from Kīpahulu Valley, Haleakalā National Park, on the island of Maui, and we identified primary larval habitat for the mosquito vector of this disease. This intensively managed wilderness area and scientific reserve is one of the most pristine areas of native forest remaining in the state of Hawai‘i, and it will become increasingly important as a site for restoration and recovery of endangered forest birds. Overall prevalence of malarial infections in the valley was 8% (11/133) in native species and 4% (4/101) in nonnative passerines; prevalence was lower than reported for comparable elevations and habitats elsewhere in the state. Infections occurred primarily in ‘Apapane (Himatione sanguinea) and Hawai‘i ‘Amakihi (Hemignathus virens) at elevations below 1,400 m. Pox-like lesions were detected in only two Hawai‘i ‘Amakihi (2%; 2/94) at elevations below 950 m. We did not detect malaria or pox in birds caught at 1,400 m in upper reaches of the valley. Adult mosquitoes (Culex quinquefasciatus) were captured at four sites at elevations of 640, 760, 915, and 975 m, respectively. Culex quinquefasciatus larvae were found only in rock holes along intermittent tributaries of the two largest streams in the valley, but not in standing surface water, pig wallows, ground pools, tree cavities, and tree fern cavities. Mosquito populations in the valley are low, and they are probably influenced by periods of high rainfall that flush stream systems.

  8. Ward Valley transfer stalled by Babbitt

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    Interior Secretary Bruce Babbitt announced on November 24 that he would not authorize the land transfer for the proposed low-level waste disposal site at Ward Valley, California, until a legal challenge to the facility's license and environmental impact statement is resolved. Even if the matter is resolved quickly, there exists the possibility that yet another hearing will be held on the project, even though state courts in California have stated flatly that no such hearings are required

  9. Ward Valley transfer stalled by Babbitt

    Energy Technology Data Exchange (ETDEWEB)

    1994-01-01

    Interior Secretary Bruce Babbitt announced on November 24 that he would not authorize the land transfer for the proposed low-level waste disposal site at Ward Valley, California, until a legal challenge to the facility's license and environmental impact statement is resolved. Even if the matter is resolved quickly, there exists the possibility that yet another hearing will be held on the project, even though state courts in California have stated flatly that no such hearings are required.

  10. Willamette Valley Ecoregion: Chapter 3 in Status and trends of land change in the Western United States--1973 to 2000

    Science.gov (United States)

    Wilson, Tamara S.; Sorenson, Daniel G.

    2012-01-01

    The Willamette Valley Ecoregion (as defined by Omernik, 1987; U.S. Environmental Protection Agency, 1997) covers approximately 14,458 km² (5,582 mi2), making it one of the smallest ecoregions in the conterminous United States. The long, alluvial Willamette Valley, which stretches north to south more than 193 km and ranges from 32 to 64 km wide, is nestled between the sedimentary and metamorphic Coast Ranges (Coast Range Ecoregion) to the west and the basaltic Cascade Range (Cascades Ecoregion) to the east (fig. 1). The Lewis and Columbia Rivers converge at the ecoregion’s northern boundary in Washington state; however, the majority of the ecoregion falls within northwestern Oregon. Interstate 5 runs the length of the valley to its southern boundary with the Klamath Mountains Ecoregion. Topography here is relatively flat, with elevations ranging from sea level to 122 m. This even terrain, coupled with mild, wet winters, warm, dry summers, and nutrient-rich soil, makes the Willamette Valley the most important agricultural region in Oregon. Population centers are concentrated along the valley floor. According to estimates from the Oregon Department of Fish and Wildlife (2006), over 2.3 million people lived in Willamette Valley in 2000. Portland, Oregon, is the largest city, with 529,121 residents (U.S. Census Bureau, 2000). Other sizable cities include Eugene, Oregon; Salem (Oregon’s state capital); and Vancouver, Washington. Despite the large urban areas dotting the length of the Willamette Valley Ecoregion, agriculture and forestry products are its economic foundation (figs. 2,3). The valley is a major producer of grass seed, ornamental plants, fruits, nuts, vegetables, and grains, as well as poultry, beef, and dairy products. The forestry and logging industries also are primary employers of the valley’s rural residents (Rooney, 2008). These activities have affected the watershed significantly, with forestry and agricultural runoff contributing to river

  11. Ground water in Dale Valley, New York

    Science.gov (United States)

    Randall, Allan D.

    1979-01-01

    Dale Valley is a broad valley segment, enlarged by glacial erosion, at the headwaters of Little Tonawanda Creek near Warsaw , New York. A thin, shallow alluvial aquifer immediately underlies the valley floor but is little used. A deeper gravel aquifer, buried beneath many feet of lake deposits, is tapped by several industrial wells. A finite-difference digital model treated the deep aquifer as two-dimensional with recharge and discharge through a confining layer. It was calibrated by simulating (1) natural conditions, (2) an 18-day aquifer test, and (3) 91 days of well-field operation. Streamflow records and model simulations suggest that in moderately wet years such as 1974, a demand of 750 gallons per minute could be met by withdrawal from the creek and from the aquifer without excessive drawdown at production wells or existing domestic wells. With reasonable but unverified model adjustments to simulate an unusually dry year, the model predicts that a demand of 600 gallons per minute could be met from the same sources. Water high in chloride has migrated from bedrock into parts of the deep aquifer. Industrial pumpage, faults in the bedrock, and the natural flow system may be responsible. (Woodard-USGS)

  12. Characterization of Solang valley watershed in western Himalaya for bio-resource conservation using remote sensing techniques.

    Science.gov (United States)

    Kumar, Amit; Chawla, Amit; Rajkumar, S

    2011-08-01

    The development activities in mountainous region though provide comfort to the human being and enhance the socioeconomic status of the people but create pressure on the bio-resources. In this paper, the current status of land use/landcover and the vegetation communities of the Solang valley watershed in Himachal Pradesh of Indian western Himalaya has been mapped and presented using remote sensing. This watershed area was dominated by alpine and sub-alpine pastures (30.34%) followed by scree slopes (22.34%) and forests (21.06%). Many tree, shrub, and herb species identified in the study area are among the prioritized species for conservation in the Indian Himalayan Region. Thus, scientific interventions and preparation of action plans based on ecological survey are required for conservation of the Solang valley watershed.

  13. Forest dynamics.

    Science.gov (United States)

    Frelich, Lee

    2016-01-01

    Forest dynamics encompass changes in stand structure, species composition, and species interactions with disturbance and environment over a range of spatial and temporal scales. For convenience, spatial scale is defined as individual tree, neighborhood, stand, and landscape. Whether a given canopy-leveling disturbance will initiate a sequence of development in structure with little change in composition or initiate an episode of succession depends on a match or mismatch, respectively, with traits of the dominant tree species that allow the species to survive disturbance. When these match, certain species-disturbance type combinations lock in a pattern of stand and landscape dynamics that can persist for several generations of trees; thus, dominant tree species regulate, as well as respond to, disturbance. A complex interaction among tree species, neighborhood effects, disturbance type and severity, landform, and soils determines how stands of differing composition form and the mosaic of stands that compose the landscape. Neighborhood effects (e.g., serotinous seed rain, sprouting, shading, leaf-litter chemistry, and leaf-litter physical properties) operate at small spatial extents of the individual tree and its neighbors but play a central role in forest dynamics by contributing to patch formation at stand scales and dynamics of the entire landscape. Dominance by tree species with neutral to negative neighborhood effects leads to unstable landscape dynamics in disturbance-prone regions, wherein most stands are undergoing succession; stability can only occur under very low-severity disturbance regimes. Dominance by species with positive effects leads to stable landscape dynamics wherein only a small proportion of stands undergo succession at any one time. Positive neighborhood effects are common in temperate and boreal zones, whereas negative effects are more common in tropical climates. Landscapes with positive dynamics have alternate categories of dynamics

  14. Influences on wood load in mountain streams of the Bighorn National Forest, Wyoming, USA.

    Science.gov (United States)

    Nowakowski, Amy L; Wohl, Ellen

    2008-10-01

    We documented valley and channel characteristics and wood loads in 19 reaches of forested headwater mountain streams in the Bighorn National Forest of northern Wyoming. Ten of these reaches were in the Upper Tongue River watershed, which has a history of management including timber harvest, tie floating, and road construction. Nine reaches were in the North Rock Creek watershed, which has little history of management activities. We used these data to test hypotheses that (i) valley geometry correlates with wood load, (ii) stream gradient correlates with wood load, and (iii) wood loads are significantly lower in managed watersheds than in otherwise similar unmanaged watersheds. Statistical analyses of the data support the first and third hypotheses. Stream reaches with steeper valley side slopes tend to have higher wood loads, and reaches in managed watersheds tend to have lower wood loads than reaches in unmanaged watersheds. Results do not support the second hypothesis. Shear stress correlated more strongly with wood load than did stream gradient, but statistical models with valley-scale variables had greater explanatory power than statistical models with channel-scale variables. Wood loads in stream reaches within managed watersheds in the Bighorn National Forest tend to be two to three times lower than wood loads in unmanaged watersheds.

  15. Competition between the inter-valley scattering and the intra-valley scattering on magnetoconductivity induced by screened Coulomb disorder in Weyl semimetals

    Directory of Open Access Journals (Sweden)

    Xuan-Ting Ji

    2017-10-01

    Full Text Available Recent experiments on Weyl semimetals reveal that charged impurities may play an important role. We use a screened Coulomb disorder to model the charged impurities, and study the magneto-transport in a two-node Weyl semimetal. It is found that when the external magnetic field is applied parallel to the electric field, the calculated longitudinal magnetoconductivity shows positive in the magnetic field, which is just the negative longitudinal magnetoresistivity (LMR observed in experiments. When the two fields are perpendicular to each other, the transverse magnetoconductivities are measured. It is found that the longitudinal (transverse magnetoconductivity is suppressed (enhanced sensitively with increasing the screening length. This feature makes it hardly to observe the negative LMR in Weyl semimetals experimentally owing to a small screening length. Our findings gain insight into further understanding on recently actively debated magneto-transport behaviors in Weyl semimetals. Furthermore we studied the relative weight of the inter-valley scattering and the intra-valley scattering. It shows that the former is as important as the latter and even dominates in the case of strong magnetic fields and small screening length. We emphasize that the discussions on inter-valley scattering is out of the realm of one-node model which has been studied.

  16. Forest and climate change

    International Nuclear Information System (INIS)

    2009-01-01

    After having recalled the challenges the French forest has to face, and a brief overview of the status of forests in the world, this report proposes an overview of actions which are implemented to strengthen the carbon sequestration role of forests, at the international level and in France. It discusses the distribution of carbon, the forest carbon stocks (in the world, Europe and France), the actions against climate change, the costs and financing of the reduction of greenhouse gas emissions in the forest sector. It comments the status of international negotiations and how forests are taken into account. It presents the French forest and wood sector (characteristics of the forest in metropolitan France and overseas, wood as material and as energy). It recalls the commitment of the Grenelle de l'Environnement, and indicates the current forest studies

  17. Virgin Valley opal district, Humboldt County, Nevada

    Science.gov (United States)

    Staatz, Mortimer Hay; Bauer, Herman L.

    1951-01-01

    The Virgin Valley opal district, Humboldt County, Nevada, is near the Oregon-Nevada border in the Sheldon Game Refuge. Nineteen claims owned by Jack and Toni Crane were examined, sampled, and tested radiometrically for uranium. Numerous discontinuous layers of opal are interbedded with a gently-dipping series of vitric tuff and ash which is at least 300 ft thick. The tuff and ash are capped by a dark, vesicular basalt in the eastern part of the area and by a thin layer of terrace qravels in the area along the west side of Virgin Valley. Silicification of the ash and tuff has produced a rock that ranges from partly opalized rock that resembles silicified shale to completely altered rock that is entirely translucent, and consists of massive, brown and pale-green opal. Carnotite, the only identified uranium mineral, occurs as fracture coatings or fine layers in the opal; in places, no uranium minerals are visible in the radioactive opal. The opal layers are irregular in extent and thickness. The exposed length of the layers ranges from 8 to 1, 200 ft or more, and the thickness of the layers ranges from 0. 1 to 3. 9 ft. The uranium content of each opal layer, and of different parts of the same layer, differs widely. On the east side of Virgin Valley four of the seven observed opal layers, nos. 3, 4, 5, and 7, are more radioactive than the average; and the uranium content ranges from 0. 002 to 0. 12 percent. Two samples, taken 5 ft apart across opal layer no. 7, contained 0. 003 and 0. -049 percent uranium. On the west side of the valley only four of the fifteen observed opal layers, nos; 9, , 10, 14, and 15, are more radioactive than the average; and the uranium content ranges from 0. 004 to 0. 047 percent. Material of the highest grade was found in a small discontinuous layer of pale-green opal (no. 4) on the east side of Virgin Valley. The grade of this layer ranged from 0. 027 to 0. 12 percent uranium.

  18. About the issue of monitoring method of Ararat valley soils salinization

    Directory of Open Access Journals (Sweden)

    A.G. Yeghiazaryan

    2017-12-01

    Full Text Available The short description of the agro-ameliorative situation of the Republic of Armenia, particularly, that of Ararat valley shows that the unpredictable and unmanageable process of regime procedures at this area can cause serious consequences, pushing out the agricultural golden fund of the republic from the agricultural turnover, namely the land of Ararat valley. Numerous investigations on the soil reclaimed state in Ararat valley at the Republic of Armenia reveal that they are currently in an extremely threatening condition. The result analyses show that more than 35% of Ararat valley lands of agricultural importance are in insufficiently reclaimed state, moreover the 54% of them are weakly salinized, 11,8% are averagely and strongly salinized and 34.2% are strongly salinized. The analyses of the conducted theoretical and experimental research results show that the above mentioned negative processes are promoted by the depth of the ground water allocation, which in Ararat valley fluctuates within the depth of 1 m, 1-3 m and more than 3 m. According to the distribution area the ground waters on 6,6% land areas of Ararat valley irrigated soils are allocated at the depth of 1 m, in 27,8% land areas the ground waters are allocated at the depth of 1–3 m, and in the rest of 65,6% land area waters are allocated at the depth of more than 3 m. For the prevention of the soils salinization process at Ararat valley and for the development of measures for struggling against it, the impact of ground waters installation depth, their mineralization, calculated evapo-transpiration from the soil and plants, irrigation norm, watering regime and technique, pressure nutrition caused from underground water basin and the impact of evaporation raising from the ground water surfaces on the ground waters level change in the vegetation period is evaluated in the current work. For the evaluation of the above mentioned individual factors the integral

  19. The Impact of Forest Density on Forest Height Inversion Modeling from Polarimetric InSAR Data

    Directory of Open Access Journals (Sweden)

    Changcheng Wang

    2016-03-01

    Full Text Available Forest height is of great significance in analyzing the carbon cycle on a global or a local scale and in reconstructing the accurate forest underlying terrain. Major algorithms for estimating forest height, such as the three-stage inversion process, are depending on the random-volume-over-ground (RVoG model. However, the RVoG model is characterized by a lot of parameters, which influence its applicability in forest height retrieval. Forest density, as an important biophysical parameter, is one of those main influencing factors. However, its influence to the RVoG model has been ignored in relating researches. For this paper, we study the applicability of the RVoG model in forest height retrieval with different forest densities, using the simulated and real Polarimetric Interferometric SAR data. P-band ESAR datasets of the European Space Agency (ESA BioSAR 2008 campaign were selected for experiments. The test site was located in Krycklan River catchment in Northern Sweden. The experimental results show that the forest density clearly affects the inversion accuracy of forest height and ground phase. For the four selected forest stands, with the density increasing from 633 to 1827 stems/Ha, the RMSEs of inversion decrease from 4.6 m to 3.1 m. The RVoG model is not quite applicable for forest height retrieval especially in sparsely vegetated areas. We conclude that the forest stand density is positively related to the estimation accuracy of the ground phase, but negatively correlates to the ground-to-volume scattering ratio.

  20. Valley and spin thermoelectric transport in ferromagnetic silicene junctions

    International Nuclear Information System (INIS)

    Ping Niu, Zhi; Dong, Shihao

    2014-01-01

    We have investigated the valley and spin resolved thermoelectric transport in a normal/ferromagnetic/normal silicene junction. Due to the coupling between the valley and spin degrees of freedom, thermally induced pure valley and spin currents can be demonstrated. The magnitude and sign of these currents can be manipulated by adjusting the ferromagnetic exchange field and local external electric field, thus the currents are controllable. We also find fully valley and/or spin polarized currents. Similar to the currents, owing to the band structure symmetry, tunable pure spin and/or valley thermopowers with zero charge counterpart are generated. The results obtained here suggest a feasible way of generating a pure valley (spin) current and thermopower in silicene

  1. Valley-orbit hybrid states in Si quantum dots

    Science.gov (United States)

    Gamble, John; Friesen, Mark; Coppersmith, S. N.

    2013-03-01

    The conduction band for electrons in layered Si nanostructures oriented along (001) has two low-lying valleys. Most theoretical treatments assume that these valleys are decoupled from the long-wavelength physics of electron confinement. In this work, we show that even a minimal amount of disorder (a single atomic step at the quantum well interface) is sufficient to mix valley states and electron orbitals, causing a significant distortion of the long-wavelength electron envelope. For physically realistic electric fields and dot sizes, this valley-orbit coupling impacts all electronic states in Si quantum dots, implying that one must always consider valley-orbit hybrid states, rather than distinct valley and orbital degrees of freedom. We discuss the ramifications of our results on silicon quantum dot qubits. This work was supported in part by ARO (W911NF-08-1-0482) and NSF (DMR-0805045).

  2. Valley Hall effect and Nernst effect in strain engineered graphene

    Science.gov (United States)

    Niu, Zhi Ping; Yao, Jian-ming

    2018-04-01

    We theoretically predict the existence of tunneling valley Hall effect and Nernst effect in the normal/strain/normal graphene junctions, where a strained graphene is sandwiched by two normal graphene electrodes. By applying an electric bias a pure transverse valley Hall current with longitudinal charge current is generated. If the system is driven by a temperature bias, a valley Nernst effect is observed, where a pure transverse valley current without charge current propagates. Furthermore, the transverse valley current can be modulated by the Fermi energy and crystallographic orientation. When the magnetic field is further considered, we obtain a fully valley-polarized current. It is expected these features may be helpful in the design of the controllable valleytronic devices.

  3. Carbon sequestration in managed temperate coniferous forests under climate change

    Science.gov (United States)

    Dymond, Caren C.; Beukema, Sarah; Nitschke, Craig R.; Coates, K. David; Scheller, Robert M.

    2016-03-01

    Management of temperate forests has the potential to increase carbon sinks and mitigate climate change. However, those opportunities may be confounded by negative climate change impacts. We therefore need a better understanding of climate change alterations to temperate forest carbon dynamics before developing mitigation strategies. The purpose of this project was to investigate the interactions of species composition, fire, management, and climate change in the Copper-Pine Creek valley, a temperate coniferous forest with a wide range of growing conditions. To do so, we used the LANDIS-II modelling framework including the new Forest Carbon Succession extension to simulate forest ecosystems under four different productivity scenarios, with and without climate change effects, until 2050. Significantly, the new extension allowed us to calculate the net sector productivity, a carbon accounting metric that integrates aboveground and belowground carbon dynamics, disturbances, and the eventual fate of forest products. The model output was validated against literature values. The results implied that the species optimum growing conditions relative to current and future conditions strongly influenced future carbon dynamics. Warmer growing conditions led to increased carbon sinks and storage in the colder and wetter ecoregions but not necessarily in the others. Climate change impacts varied among species and site conditions, and this indicates that both of these components need to be taken into account when considering climate change mitigation activities and adaptive management. The introduction of a new carbon indicator, net sector productivity, promises to be useful in assessing management effectiveness and mitigation activities.

  4. Forest inventory in Myanmar

    Energy Technology Data Exchange (ETDEWEB)

    Bo, Sit [Forest Resource Div., Forest Department (Myanmar)

    1993-10-01

    Forest inventory in Myanmar started in 1850s. Up till 1975, Myanmar Forest Department conducted forest inventories covering approximately one forest division every year. The National Forest Survey and Inventory Project funded by UNDP and assisted by FAO commenced in 1981 and the National Forest Management and Inventory project followed in 1986. Up till end March 1993, pre-investment inventory has covered 26.7 million acres, reconnaissance inventory 5.4 million acres and management inventory has carried out in 12 townships

  5. Forest inventory in Myanmar

    International Nuclear Information System (INIS)

    Sit Bo

    1993-01-01

    Forest inventory in Myanmar started in 1850s. Up till 1975, Myanmar Forest Department conducted forest inventories covering approximately one forest division every year. The National Forest Survey and Inventory Project funded by UNDP and assisted by FAO commenced in 1981 and the National Forest Management and Inventory project followed in 1986. Up till end March 1993, pre-investment inventory has covered 26.7 million acres, reconnaissance inventory 5.4 million acres and management inventory has carried out in 12 townships

  6. Forest resources of Mississippi’s national forests, 2006

    Science.gov (United States)

    Sonja N. Oswalt

    2011-01-01

    This bulletin describes forest resource characteristics of Mississippi’s national forests, with emphasis on DeSoto National Forest, following the 2006 survey completed by the U.S. Department of Agriculture Forest Service, Forest Inventory and Analysis program. Mississippi’s national forests comprise > 1 million acres of forest land, or about 7 percent of all forest...

  7. Observations of Air Quality at the Edge of Kathmandu, Nepal, and the Diurnal Cycle of Air Pollution In and Around the Kathmandu Valley

    Science.gov (United States)

    Panday, A. K.; Prinn, R. G.; Regmi, R. P.

    2006-12-01

    The Kathmandu Valley is a bowl-shaped basin in the Nepal Himalaya, with a rapidly growing city surrounded by rice fields and steep terraced and forested mountain slopes. The valley's air quality is influenced by urban and rural emissions, nocturnal pooling of cold air, slope winds, and a daily exchange of air through mountain passes. To understand these processes and to inform air pollution policy in Nepal, we have carried out the most comprehensive study of air pollution in Nepal to date. During the 9-month dry season of 2004-2005, we carried out continuous measurements every minute of carbon monoxide, ozone, PM10, wind speed, wind direction, solar radiation, temperature, and humidity on the eastern edge of Kathmandu city, at a site that daily received air from both the city and rural areas. We recorded the diurnal cycle of the vertical temperature structure and stability with temperature loggers on towers and mountains. A sodar measured the mixed layer height and upper-level winds. 24-hour simultaneous bag sampling campaigns on mountain peaks, passes, the rural valley, and within the city provided glimpses of the spatial patterns of the diurnal cycle of CO -- a useful tracer of anthropogenic emissions. We measured winds on mountain passes and ozone on mountain peaks. At our main measurement site we found a daily-recurring pattern of CO and PM10, with an afternoon low showing rural background levels, even though the arriving air had traversed the city. This was followed by an evening peak starting at sunset, a second low late at night, and a morning peak enhanced by re-circulation. Pollutants emitted in the valley only traveled out of the valley between the late morning and sunset. During winter months, rush hour was outside of this period, enhancing the morning and evening peaks. Within the city, ozone dropped to zero at night. At mid-day we observed an ozone peak enhanced by photochemical production when the air mass that had been stagnant over the city swept

  8. MX Siting Investigation. Gravity Survey - Sevier Desert Valley, Utah.

    Science.gov (United States)

    1981-01-24

    Cheyenne, Wyoming. DMAHTC reduces the data to Simple Bouguer Anomaly (see Section A1.4, Appendix Al.0). The Defense Mapping Agency Aerospace Center...Desert Valley, Utah ......... 2 2 Topographic Setting - Sevier Desert Valley, Utah . 3 LIST OF DRAWINGS Drawing Number 1 Complete Bouguer Anomaly...gravity stations were distributed throughout the valley at an approxi- mate interval of 1.4 miles (2.3 km). Drawing 1 is a Complete Bouguer Anomaly

  9. Late Quaternary paleoenvironmental records from the Chatanika River valley near Fairbanks (Alaska)

    Science.gov (United States)

    Schirrmeister, Lutz; Meyer, Hanno; Andreev, Andrei; Wetterich, Sebastian; Kienast, Frank; Bobrov, Anatoly; Fuchs, Margret; Sierralta, Melanie; Herzschuh, Ulrike

    2016-09-01

    Perennially-frozen deposits are considered as excellent paleoenvironmental archives similar to lacustrine, deep marine, and glacier records because of the long-term and good preservation of fossil records under stable permafrost conditions. A permafrost tunnel in the Vault Creek Valley (Chatanika River Valley, near Fairbanks) exposes a sequence of frozen deposits and ground ice that provides a comprehensive set of proxies to reconstruct the late Quaternary environmental history of Interior Alaska. The multi-proxy approach includes different dating techniques (radiocarbon-accelerator mass spectrometry [AMS 14C], optically stimulated luminescence [OSL], thorium/uranium radioisotope disequilibria [230Th/U]), as well as methods of sedimentology, paleoecology, hydrochemistry, and stable isotope geochemistry of ground ice. The studied sequence consists of 36-m-thick late Quaternary deposits above schistose bedrock. Main portions of the sequence accumulated during the early and middle Wisconsin periods. The lowermost unit A consists of about 9-m-thick ice-bonded fluvial gravels with sand and peat lenses. A late Sangamon (MIS 5a) age of unit A is assumed. Spruce forest with birch, larch, and some shrubby alder dominated the vegetation. High presence of Sphagnum spores and Cyperaceae pollen points to mires in the Vault Creek Valley. The overlying unit B consists of 10-m-thick alternating fluvial gravels, loess-like silt, and sand layers, penetrated by small ice wedges. OSL dates support a stadial early Wisconsin (MIS 4) age of unit B. Pollen and plant macrofossil data point to spruce forests with some birch interspersed with wetlands around the site. The following unit C is composed of 15-m-thick ice-rich loess-like and organic-rich silt with fossil bones and large ice wedges. Unit C formed during the interstadial mid-Wisconsin (MIS 3) and stadial late Wisconsin (MIS 2) as indicated by radiocarbon ages. Post-depositional slope processes significantly deformed both, ground

  10. Forest report 2013; Waldzustandsbericht 2013

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-07-01

    This forest report of Lower Saxony (Germany) contains the following topics: weather and climate, forest protection, crown defoliation, infiltrated substances, environmental monitoring, insects and fungi, forest soil survey and forest site mapping, and nutritional status of beech on loess.

  11. Selection of a reference process for treatment of the West Valley alkaline waste

    International Nuclear Information System (INIS)

    Holton, L.K.; Wise, B.M.; Bray, L.A.; Pope, J.M.; Carl, D.E.

    1984-08-01

    As part of the West Valley Demonstration Project (WVDP) the alkaline PUREX supernatant stored in Tank 8D2 will be partially decontaminated by the removal of radiocesium. Four processes for removal of radiocesium from the alkaline supernatant were studied through experimentation and engineering analysis to identify a reference approach for the WVDP. These processes included the use of a zeolite inorganic ion-exchanger (Linde Ionsiv IE-95), an organic ion exchange resin (Duolite CS-100), and two precipitation processes; one using sodium tetraphenylboron (NaTPB) and the other using phosphotungstic acid (PTA). Based upon process performance, safety and environmental considerations, process and equipment complexity and impacts to the waste vitrification system, the zeolite ion-exchange process has been selected by West Valley Nuclear Services, Inc., as the reference supernatant treatment process for the WVDP. This paper will summarize the technical basis for the selection of the zeolite ion-exchange process. 4 figures, 2 tables

  12. Valley polarized quantum Hall effect and topological insulator phase transitions in silicene

    KAUST Repository

    Tahir, M.

    2013-01-25

    The electronic properties of silicene are distinct from both the conventional two dimensional electron gas and the famous graphene due to strong spin orbit interaction and the buckled structure. Silicene has the potential to overcome limitations encountered for graphene, in particular the zero band gap and weak spin orbit interaction. We demonstrate a valley polarized quantum Hall effect and topological insulator phase transitions. We use the Kubo formalism to discuss the Hall conductivity and address the longitudinal conductivity for elastic impurity scattering in the first Born approximation. We show that the combination of an electric field with intrinsic spin orbit interaction leads to quantum phase transitions at the charge neutrality point, providing a tool to experimentally tune the topological state. Silicene constitutes a model system for exploring the spin and valley physics not accessible in graphene due to the small spin orbit interaction.

  13. Disorder-dependent valley properties in monolayer WSe2

    KAUST Repository

    Tran, Kha

    2017-07-19

    We investigate the effect of disorder on exciton valley polarization and valley coherence in monolayer WSe2. By analyzing the polarization properties of photoluminescence, the valley coherence (VC) and valley polarization (VP) are quantified across the inhomogeneously broadened exciton resonance. We find that disorder plays a critical role in the exciton VC, while affecting VP less. For different monolayer samples with disorder characterized by their Stokes shift (SS), VC decreases in samples with higher SS while VP does not follow a simple trend. These two methods consistently demonstrate that VC as defined by the degree of linearly polarized photoluminescence is more sensitive to disorder, motivating further theoretical studies.

  14. Seven-year responses of trees to experimental hurricane effects in a tropical rainforest, Puerto Rico

    Science.gov (United States)

    Jess K. Zimmerman; James Aaron Hogan; Aaron B. Shiels; John E. Bithorn; Samuel Matta Carmona; Nicholas Brokaw

    2014-01-01

    We experimentally manipulated key components of severe hurricane disturbance, canopy openness and detritus deposition, to determine the independent and interactive effects of these components on tree recruitment, forest structure, and diversity in a wet tropical forest in the Luquillo Experimental Forest, Puerto Rico. Canopy openness was increased by trimming branches...

  15. Spatial patterns of degraded tropical forest and biodiversity restoration over 70-years of succession

    Directory of Open Access Journals (Sweden)

    Janet E. Nichol

    2017-07-01

    Full Text Available Landscape metrics have often been used to analyse the spatial dynamics of habitat fragmentation accompanying forest loss. However, there are few studies of the spatial dynamics of natural forest succession, especially over periods longer than the operational period of imaging satellites. This study applies spatial metrics to understand the spatial processes of a 70-year tropical secondary forest succession in Hong Kong, since World War 2. The highest rate of forest regeneration at 11% a year from 1989 to 2001 occurred when the landscape achieved greatest habitat diversity and juxtapositioning of habitat patches. This rapid regeneration occurred by infilling from remnant forest in adjacent valleys rather than by an advance along a broad forest front, and led to simplification of the landscape and declining habitat diversity. It was also accompanied by declines in species richness and abundance in regenerated forest patches. Thus both habitat and woody plant species diversity show a humped trend over the successional period as disconnected forest patches amalgamate, and shade-intolerant pioneers are shaded out by taller pioneers. From this point onwards, the birds of mixed habitats including bulbuls and hwamei known to disperse seed in the study area, may become less effective as forest patches consolidate, and only a few forest mammals remain. The observed improved connectivity within forest patches and reduced edge disturbances accompanying landscape simplification provide better conditions for dispersion within forest of light-intolerant climax species from the oldest, species-rich valley sites to the newly regenerated areas. However, in addition to the loss of forest dispersal agents, other natural dispersal agents such as gravity, flash floods and slope wash involving downward processes may be ineffective, as forest has regenerated upwards to higher elevations. Progression to a mature, biodiverse and stable forest ecosystem may depend on

  16. Practical aspects of registration the transformation of a river valley by beavers using terrestrial laser scanning

    Science.gov (United States)

    Tyszkowski, Sebastian; Błaszkiewicz, Mirosław; Brykała, Dariusz; Gierszewski, Piotr; Kaczmarek, Halina; Kordowski, Jarosław; Słowiński, Michał

    2016-04-01

    Activity of beavers (Castor fiber) often significantly affects the environment in which they life. The most commonly observed effect of their being in environment is construction of beaver dams and formation a pond upstream. However, in case of a sudden break of a dam and beaver pond drainage, the valley below the dam may also undergo remodelling. The nature and magnitude of these changes depends on the quantity of water and its energy as well as on the geological structure of the valley. The effects of such events can be riverbank erosion, and the deposition of the displaced of erosion products in the form of sandbars or fans. The material can also be accumulated in local depressions or delivered to water bodies. Such events may occur multiple times in the same area. To assess their impact on the environment it is important to quantify the displaced material. The study of such transformations was performed within a small valley of the river of Struga Czechowska (Tuchola Pinewood Forest, Poland). The valley is mainly cut in sands and gravels. Its steep banks are overgrown with bushes and trees. The assessment of changes in morphology were based on the event of the beaver pond drainage of 2015. The study uses the measurements from the terrestrial laser scanning (scanner Riegl VZ-4000). The measurements were performed before and after the event. Each of the two models obtained for comparison was made up of more than 20 measurement stations. Point clouds were joined by Multi-Station Adjustment without placing in the terrain any objects of reference. During measurements attention was paid to the changes in morphology of both riverbed and valley surrounding. The paper presents the example of the recorded changes as well as the measurement procedure. Moreover, the aspects of fieldwork and issues related to post-processing, such as merging, filtering of point clouds and detection of changes, are also presented. This study is a contribution to the Virtual Institute of

  17. Impact of wild ungulates on coppices from the Bisenzio Valley (province of Prato, Italy

    Directory of Open Access Journals (Sweden)

    Bianchi L

    2014-06-01

    Full Text Available Similar to other Apennine areas, a considerable increase of wild ungulate density has been observed in the past decades in the Bisenzio valley (province of Prato, leading to a strong impact on coppice regeneration. In some felling areas, the prolonged browsing on young suckers turned the stumps into low and dense bushes, thus threatening the survival of the forest stand and triggering a loss of environmental stability. The aim of this work was to study the impact of deer on sprout regeneration after cutting in mixed coppices felled in the period 2007-2010 and characterized by the dominance of chestnut, hornbeam, Turkey oak, and beech. Some 36 plots were established in four municipal districts of the Prato province (Cantagallo, Vernio, Montemurlo, Vaiano. Damage and browsing intensity on each stump were evaluated using an index that allowed the comparison among different areas and fores stand types. Regardless of the species, over 90% of the sprouts revealed a very strong damage, whereas only 6% did not exhibit any damage. A significant difference in the sprout height was detected between browsed and non-browsed areas. Despite a high incidence of damage in all the studied areas, chestnut showed a greater resilience against browsing. In summary, overgrazing by wild game may determine severe contraints to the evolutionary dynamics of forest stands, frustrating the effects of silvicultural practices. The possible benefits of the implementation of a large-scale integrated wildlife plan, including hunting and forest-evironmental management are discussed.

  18. Forest management strategy, spatial heterogeneity, and winter birds in Washington.

    Science.gov (United States)

    B. Haveri; A.B. Carey

    2000-01-01

    Ecological management of second-growth forest holds great promise for conservation of biodiversity, yet little experimental evidence exists to compare alternative management approaches. Wintering birds are one of several groups of species most likely to be influenced by forest management activities. We compared species richness and proportion of stand area used over...

  19. National Forest Boundaries

    Data.gov (United States)

    Minnesota Department of Natural Resources — This theme shows the USFS national forest boundaries in the state. This data was acquired from the GIS coordinators at both the Chippewa National Forest and the...

  20. Forest Grammar (Ⅱ)

    Institute of Scientific and Technical Information of China (English)

    张松懋

    1994-01-01

    The syntactic parsing algorithm of weak precedence forest grammar has been introduced and the correctness and unambiguity of this algorithm have been proved. An example is given to the syntactic parsing procedure of weak precedence forest grammar.

  1. Relating P-band AIRSAR backscatter to forest stand parameters

    Science.gov (United States)

    Wang, Yong; Melack, John M.; Davis, Frank W.; Kasischke, Eric S.; Christensen, Norman L., Jr.

    1993-01-01

    As part of research on forest ecosystems, the Jet Propulsion Laboratory (JPL) and collaborating research teams have conducted multi-season airborne synthetic aperture radar (AIRSAR) experiments in three forest ecosystems including temperate pine forest (Duke, Forest, North Carolina), boreal forest (Bonanza Creek Experimental Forest, Alaska), and northern mixed hardwood-conifer forest (Michigan Biological Station, Michigan). The major research goals were to improve understanding of the relationships between radar backscatter and phenological variables (e.g. stand density, tree size, etc.), to improve radar backscatter models of tree canopy properties, and to develop a radar-based scheme for monitoring forest phenological changes. In September 1989, AIRSAR backscatter data were acquired over the Duke Forest. As the aboveground biomass of the loblolly pine forest stands at Duke Forest increased, the SAR backscatter at C-, L-, and P-bands increased and saturated at different biomass levels for the C-band, L-band, and P-band data. We only use the P-band backscatter data and ground measurements here to study the relationships between the backscatter and stand density, the backscatter and mean trunk dbh (diameter at breast height) of trees in the stands, and the backscatter and stand basal area.

  2. Surface slip during large Owens Valley earthquakes

    KAUST Repository

    Haddon, E. K.; Amos, C. B.; Zielke, Olaf; Jayko, A. S.; Burgmann, R.

    2016-01-01

    The 1872 Owens Valley earthquake is the third largest known historical earthquake in California. Relatively sparse field data and a complex rupture trace, however, inhibited attempts to fully resolve the slip distribution and reconcile the total moment release. We present a new, comprehensive record of surface slip based on lidar and field investigation, documenting 162 new measurements of laterally and vertically displaced landforms for 1872 and prehistoric Owens Valley earthquakes. Our lidar analysis uses a newly developed analytical tool to measure fault slip based on cross-correlation of sublinear topographic features and to produce a uniquely shaped probability density function (PDF) for each measurement. Stacking PDFs along strike to form cumulative offset probability distribution plots (COPDs) highlights common values corresponding to single and multiple-event displacements. Lateral offsets for 1872 vary systematically from approximate to 1.0 to 6.0 m and average 3.31.1 m (2 sigma). Vertical offsets are predominantly east-down between approximate to 0.1 and 2.4 m, with a mean of 0.80.5 m. The average lateral-to-vertical ratio compiled at specific sites is approximate to 6:1. Summing displacements across subparallel, overlapping rupture traces implies a maximum of 7-11 m and net average of 4.41.5 m, corresponding to a geologic M-w approximate to 7.5 for the 1872 event. We attribute progressively higher-offset lateral COPD peaks at 7.12.0 m, 12.8 +/- 1.5 m, and 16.6 +/- 1.4 m to three earlier large surface ruptures. Evaluating cumulative displacements in context with previously dated landforms in Owens Valley suggests relatively modest rates of fault slip, averaging between approximate to 0.6 and 1.6 mm/yr (1 sigma) over the late Quaternary.

  3. Surface slip during large Owens Valley earthquakes

    KAUST Repository

    Haddon, E. K.

    2016-01-10

    The 1872 Owens Valley earthquake is the third largest known historical earthquake in California. Relatively sparse field data and a complex rupture trace, however, inhibited attempts to fully resolve the slip distribution and reconcile the total moment release. We present a new, comprehensive record of surface slip based on lidar and field investigation, documenting 162 new measurements of laterally and vertically displaced landforms for 1872 and prehistoric Owens Valley earthquakes. Our lidar analysis uses a newly developed analytical tool to measure fault slip based on cross-correlation of sublinear topographic features and to produce a uniquely shaped probability density function (PDF) for each measurement. Stacking PDFs along strike to form cumulative offset probability distribution plots (COPDs) highlights common values corresponding to single and multiple-event displacements. Lateral offsets for 1872 vary systematically from approximate to 1.0 to 6.0 m and average 3.31.1 m (2 sigma). Vertical offsets are predominantly east-down between approximate to 0.1 and 2.4 m, with a mean of 0.80.5 m. The average lateral-to-vertical ratio compiled at specific sites is approximate to 6:1. Summing displacements across subparallel, overlapping rupture traces implies a maximum of 7-11 m and net average of 4.41.5 m, corresponding to a geologic M-w approximate to 7.5 for the 1872 event. We attribute progressively higher-offset lateral COPD peaks at 7.12.0 m, 12.8 +/- 1.5 m, and 16.6 +/- 1.4 m to three earlier large surface ruptures. Evaluating cumulative displacements in context with previously dated landforms in Owens Valley suggests relatively modest rates of fault slip, averaging between approximate to 0.6 and 1.6 mm/yr (1 sigma) over the late Quaternary.

  4. Engineering assessment of inactive uranium mill tailings: Monument Valley Site, Monument Valley, Arizona

    Energy Technology Data Exchange (ETDEWEB)

    1981-10-01

    Ford, Bacon and Davis Utah Inc. has reevalated the Monument Valley site in order to revise the March 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Monument Valley, Arizona. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposure of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 1.1 million tons of tailings at the Monument Valley site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material (Option I), to removal of the tailings to remote disposal sites and decontamination of the tailings site (Options II through IV). Cost estimates for the four options range from about $6,600,000 for stabilization in-place, to about $15,900,000 for disposal at a distance of about 15 mi. Three principal alternatives for reprocessing the Monument Valley tailings were examined: heap leaching; Treatment at an existing mill; and reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovery is economically unattractive.

  5. Engineering assessment of inactive uranium mill tailings: Monument Valley Site, Monument Valley, Arizona

    International Nuclear Information System (INIS)

    1981-10-01

    Ford, Bacon and Davis Utah Inc. has reevalated the Monument Valley site in order to revise the March 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Monument Valley, Arizona. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposure of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 1.1 million tons of tailings at the Monument Valley site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material (Option I), to removal of the tailings to remote disposal sites and decontamination of the tailings site (Options II through IV). Cost estimates for the four options range from about $6,600,000 for stabilization in-place, to about $15,900,000 for disposal at a distance of about 15 mi. Three principal alternatives for reprocessing the Monument Valley tailings were examined: heap leaching; Treatment at an existing mill; and reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovery is economically unattractive

  6. West Virginia's Forests 2008

    Science.gov (United States)

    Richard H. Widmann; Gregory W. Cook; Charles J. Barnett; Brett J. Butler; Douglas M. Griffith; Mark A. Hatfield; Cassandra M. Kurtz; Randall S. Morin; W. Keith Moser; Charles H. Perry; Ronald J. Piva; Rachel Riemann; Christopher W. Woodall

    2012-01-01

    The first full annual inventory of West Virginia's forests reports 12.0 million acres of forest land or 78 percent of the State's land area. The area of forest land has changed little since 2000. Of this land, 7.2 million acres (60 percent) are held by family forest owners. The current growing-stock inventory is 25 billion cubic feet--12 percent more than in...

  7. Forests and water cycle

    Directory of Open Access Journals (Sweden)

    Iovino F

    2009-06-01

    Full Text Available Based on a comprehensive literature analysis, a review on factors that control water cycle and water use in Mediterranean forest ecosystems is presented, including environmental variables and silvicultural treatments. This important issue is considered in the perspective of sustainable forest management of Mediterranean forests, with special regard to crucial environmental hazards such as forest fires and desertification risks related to climate change.

  8. Maine's forests 2008

    Science.gov (United States)

    George L. McCaskill; William H. McWilliams; Charles J. Barnett; Brett J. Butler; Mark A. Hatfield; Cassandra M. Kurtz; Randall S. Morin; W. Keith Moser; Charles H. Perry; Christopher W. Woodall

    2011-01-01

    The second annual inventory of Maine's forests was completed in 2008 after more than 3,160 forested plots were measured. Forest land occupies almost 17.7 million acres, which represents 82 percent of the total land area of Maine. The dominant forest-type groups are maple/beech/yellow birch, spruce/fir, white/red/jack pine, and aspen/white birch. Statewide volume...

  9. Iowa Forests, 2013

    Science.gov (United States)

    Mark D. Nelson; Charles J. Barnett; Matt Brewer; Brett J. Butler; Susan J. Crocker; Grant M. Domke; Dale D. Gormanson; Cassandra M. Kurtz; Tonya W. Lister; Stephen Matthews; William H. McWilliams; Dacia M. Meneguzzo; Patrick D. Miles; Randall S. Morin; Ronald J. Piva; Rachel Riemann; James E. Smith; Brian F. Walters; Jim Westfall; Christopher W. Woodall

    2016-01-01

    The third full annual inventory of Iowa's forests (2009-2013) indicates that just under 3 million acres of forest land exists in the State, 81 percent of which is in family forest ownership. Almost all of Iowa's forest land is timberland (96 percent), with an average volume of more than 1,000 cubic feet of growing stock per acre on timberland and more than 1,...

  10. 78 FR 59840 - Revisions to the California State Implementation Plan, Antelope Valley Air Quality Management...

    Science.gov (United States)

    2013-09-30

    ...] Revisions to the California State Implementation Plan, Antelope Valley Air Quality Management District... of plan. * * * * * (c) * * * (428) * * * (i) * * * (B) Antelope Valley Air Quality Management...) * * * (i) * * * (B) Antelope Valley Air Quality Management District. (1) Rule 431.1, ``Sulfur Content of...

  11. 78 FR 45114 - Revisions to the California State Implementation Plan, Antelope Valley Air Quality Management...

    Science.gov (United States)

    2013-07-26

    ... the California State Implementation Plan, Antelope Valley Air Quality Management District AGENCY... the Antelope Valley Air Quality Management District (AVAQMD) portion of the California State... for the South Coast Air Quality Management District (SCAQMD). The Antelope Valley Air Pollution...

  12. Dipterocarpaceae: forest fires and forest recovery

    NARCIS (Netherlands)

    Priadjati, A.

    2002-01-01

    One of the serious problems Indonesia is facing today is deforestation. Forests have been playing a very important role in Indonesia as the main natural resources for the economic growth of the country. Large areas of tropical forests, worldwide

  13. The uncanny valley in games and animation

    CERN Document Server

    Tinwell, Angela

    2014-01-01

    Advances in technology have enabled animators and video game designers to design increasingly realistic, human-like characters in animation and games. Although it was intended that this increased realism would allow viewers to appreciate the emotional state of characters, research has shown that audiences often have a negative reaction as the human likeness of a character increases. This phenomenon, known as the Uncanny Valley, has become a benchmark for measuring if a character is believably realistic and authentically human like. This book is an essential guide on how to overcome the Uncanny

  14. Neuroimaging Features of San Luis Valley Syndrome

    Directory of Open Access Journals (Sweden)

    Matthew T. Whitehead

    2015-01-01

    Full Text Available A 14-month-old Hispanic female with a history of double-outlet right ventricle and developmental delay in the setting of recombinant chromosome 8 syndrome was referred for neurologic imaging. Brain MR revealed multiple abnormalities primarily affecting midline structures, including commissural dysgenesis, vermian and brainstem hypoplasia/dysplasia, an interhypothalamic adhesion, and an epidermoid between the frontal lobes that enlarged over time. Spine MR demonstrated hypoplastic C1 and C2 posterior elements, scoliosis, and a borderline low conus medullaris position. Presented herein is the first illustration of neuroimaging findings from a patient with San Luis Valley syndrome.

  15. Mapping the Holocene forest formations with the use of key climate indicators – heat and moisture

    Directory of Open Access Journals (Sweden)

    S. K. Farber

    2017-12-01

    Full Text Available The article deals with the methodology of mapping the Holocene forest formations on the basis of the DEM and the key indicators of the climate – heat and moisture. The work is carried out by means of GIS. The test site is located within the boundaries of the axial West Sayan district of mountain taiga forests, which ensures homogeneity of natural and climatic conditions. Stages of the method: creation of rasters on groups of absolute heights, exposures and inclinations with their subsequent combination into a single Combine raster; obtaining the regularities of spatial distribution of heat and moisture and their representation in the form of rasters (digital models; and interactive mapping of the Holocene forests with various combinations of heat and moisture. The use of Combine raster makes it possible to refuse to use any other contours as – landscape, geomorphological, forest inventory. To determine parameters of climatic boundaries of forest formations, the types of forests are linked to the heat and moisture indicators. As a result of linking, a graphic image is produced, where forest formations and their productivity are located in a certain order. The mapping technique involves creating a dBASE table with a field containing information about forest formations. The row-wise change in the records of forest formations as they move to other values of heat and moisture is performed interactively. Each next combination of heat and moisture on maps corresponds to a certain distribution of forest formations and site productivity (bonitet classes. (1900 ± 65 years ago the river valleys were treeless, flat meadows occupied meadows, and the slopes were steppes. As the hypsometric level increases, larch stands, spruce-Siberian stone pine with an admixture of larch, Siberian stone pine-larch with an admixture of fir, and the Siberian stone pine formations appear. (2200 ± 100 years ago the tundra prevailed. Larch forests of V–Va classes of

  16. Trends in stream nitrogen concentrations for forested reference catchments across the USA

    Science.gov (United States)

    A. Argerich; S.L. Johnson; S.D. Sebestyen; C.C. Rhoades; E. Greathouse; J.D. Knoepp; M.B. Adams; G.E. Likens; J.L. Campbell; W.H. McDowell; F.N. Scatena; G.G. Ice

    2013-01-01

    To examine whether stream nitrogen concentrations in forested reference catchments have changed over time and if patterns were consistent across the USA, we synthesized up to 44 yr of data collected from 22 catchments at seven USDA Forest Service Experimental Forests. Trends in stream nitrogen presented high spatial variability both among catchments at a site and among...

  17. Effects of air pollution and simulated acid rain on the ground vegetation of coniferous forests

    International Nuclear Information System (INIS)

    Rodenkirchen, H.

    1993-01-01

    Descriptive and experimental studies on the ground vegetation of coniferous forests in Bavaria indicated the following phenomena: a. In N-limited pine forests recent eutrophication effects occur. b. The structure of the moss layer in coniferous forests sensitively reacts to very acid throughfall water (pH [de

  18. Connecticut's forest resources, 2010

    Science.gov (United States)

    Brett J. Butler; Cassandra Kurtz; Christopher Martin; W. Keith Moser

    2011-01-01

    This publication provides an overview of forest resource attributes for Connecticut based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) program at the Northern Research Station of the U.S. Forest Service. These estimates, along with web-posted core tables, will be updated annually. For more information please refer to page 4 of this report...

  19. Connecticut's forest resources, 2009

    Science.gov (United States)

    Brett J. Butler; Christopher Martin

    2011-01-01

    This publication provides an overview of forest resource attributes for Connecticut based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) program at the Northern Research Station of the U.S. Forest Service. These estimates, along with web-posted core tables, will be updated annually. For more information please refer to page 4 of this report...

  20. Forests of Connecticut, 2015

    Science.gov (United States)

    Brett J. Butler

    2016-01-01

    This report provides an overview of forest resources in Connecticut based on an inventory conducted by the U.S. Forest Service, Forest Inventory and Analysis (FIA) program of the Northern Research Station. Estimates are based on field data collected using the FIA annualized sample design. Results are for the measurement years 2010-2015 with comparisons made to 2005-...

  1. Vermont's Forest Resources, 2006

    Science.gov (United States)

    R.S. Morin; R. De Geus

    2008-01-01

    This publication provides an overview of forest resource attributes for Vermont based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) program at the Northern Research Station of the U.S. Forest Service. These annual estimates, along with web-posted core tables, will be updated annually. For more information regarding past inventory reports...

  2. Forests of Virginia, 2016

    Science.gov (United States)

    T.J. Brandeis; A.J. Hartsell; K.C. Randolph; C.M. Oswalt

    2018-01-01

    This resource update provides an overview of forest resources in Virginia based on an inventory conducted by the U.S. Forest Service, Forest Inventory and Analysis (FIA) program at the Southern Research Station in cooperation with the Virginia Department of Forestry.

  3. Forests of Kentucky, 2012

    Science.gov (United States)

    C.M. Oswalt

    2015-01-01

    This resource update provides an overview of forest resource attributes for the Commonwealth of Kentucky based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) Program at the Southern Research Station of the Forest Service, U.S. Department of Agriculture in cooperation with the Kentucky Department of Natural Resources Division of Forestry....

  4. Forests of Alabama, 2014

    Science.gov (United States)

    Andy Hartsell

    2016-01-01

    This resource update provides an overview of forest resources in Alabama based on an inventory conducted by the U.S. Forest Service, Forest Inventory and Analysis (FIA) program at the Southern Research Station in cooperation with the Alabama Forestry Commission. Estimates are based on field data collected using the FIA annualized sample design and are updated yearly....

  5. Forests of Wisconsin, 2013

    Science.gov (United States)

    Charles H. Perry

    2014-01-01

    This resource update provides an overview of forest resources in Wisconsin based on an inventory conducted by the U.S. Forest Service, Forest Inventory and Analysis (FIA) program at the Northern Research Station in cooperation with the Wisconsin Department of Natural Resources. Data estimates are based on field data collected using the FIA annualized sample design and...

  6. Forests of Pennsylvania, 2014

    Science.gov (United States)

    Richard H. Widmann

    2015-01-01

    This resource update provides an overview of the forest resources in Pennsylvania based on inventories conducted by the U.S. Forest Service, Forest Inventory and Analysis (FIA) program of the Northern Research Station. Estimates are based on field data collected using the FIA annualized sample design and are updated yearly (see footnote 1 on page 4). Information about...

  7. Pennsylvania's forest resources, 2012

    Science.gov (United States)

    G.L. McCaskill; W.H. McWilliams; C.J. Barnett

    2013-01-01

    This publication provides an overview of forest resource attributes for Pennsylvania based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) program at the Northern Research Station of the U.S. Forest Service. These annual estimates, along with web-posted core tables, will be updated annually. For more information please refer to page 4 of...

  8. Pennsylvania's forest resources, 2009

    Science.gov (United States)

    G.L. McCaskill; W.H. McWilliams; B.J. Butler; D.M. Meneguzzo; C.J. Barnett; M.H. Hansen

    2011-01-01

    This publication provides an overview of forest resource attributes for Pennsylvania based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) program at the Northern Research Station of the U.S. Forest Service. These annual estimates, along with web-posted core tables, will be updated annually. For more information please refer to page 4 of...

  9. Pennsylvania's forest resources, 2011

    Science.gov (United States)

    G.L. McCaskill; W.H. McWilliams; C.J. Barnett

    2012-01-01

    This publication provides an overview of forest resource attributes for Pennsylvania based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) program at the Northern Research Station of the U.S. Forest Service. These annual estimates, along with web-posted core tables, will be updated annually. For more information please refer to page 4 of...

  10. Pennsylvania's forest resources, 2008

    Science.gov (United States)

    G.L. McCaskill; W.H. McWilliams; B.J. Butler; D.M. Meneguzzo; C.J. Barnett; M.H. Hansen

    2011-01-01

    This publication provides an overview of forest resource attributes for Pennsylvania based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) program at the Northern Research Station of the U.S. Forest Service. These annual estimates, along with web-posted core tables, will be updated annually. For more information please refer to page 4 of...

  11. Forests of Pennsylvania, 2015

    Science.gov (United States)

    Richard H. Widmann

    2016-01-01

    This resource update provides an overview of the forest resources in Pennsylvania based on inventories conducted by the U.S. Forest Service, Forest Inventory and Analysis (FIA) program of the Northern Research Station (NRS). Estimates are based on field data collected using the FIA annualized sample design and are updated yearly1(see footnote 1, page 2). Information...

  12. Pennsylvania's forest resources, 2010

    Science.gov (United States)

    G.L. McCaskill; W.H. McWilliams; C.J. Barnett

    2011-01-01

    This publication provides an overview of forest resource attributes for Pennsylvania based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) program at the Northern Research Station of the U.S. Forest Service. These annual estimates, along with web-posted core tables, will be updated annually. For more information please refer to page 4 of...

  13. Pennsylvania's forest resources, 2007

    Science.gov (United States)

    G.L. McCaskill; W.H. McWilliams; B.J. Butler; D.M. Meneguzzo; C.J. Barnett; M.H. Hansen

    2011-01-01

    This publication provides an overview of forest resource attributes for Pennsylvania based on an annual inventory conducted by the Forest Inventory and Analysis (FIA) program at the Northern Research Station of the U.S. Forest Service. These annual estimates, along with web-posted core tables, will be updated annually. For more information, please refer to page 6 of...

  14. Forests of Pennsylvania, 2013

    Science.gov (United States)

    George L. McCaskill

    2014-01-01

    This publication provides an overview of the forest resources in Pennsylvania based upon inventories conducted by the USDA Forest Service, Forest Inventory and Analysis (FIA) program of the Northern Research Station. Information about the national and regional FIA program is available online at http://fia.fs.fed.us. Since 1999, FIA has implemented an annual inventory...

  15. Forests of Kansas, 2015

    Science.gov (United States)

    Dacia M. Meneguzzo

    2016-01-01

    This resource update provides an overview of forest resources in Kansas based on inventories conducted by the U.S. Forest Service, Forest Inventory and Analysis (FIA) program of the Northern Research Station. For annual inventory years 2001-2013, the sample length was equal to 5 years. Beginning in 2014, the cycle length was changed to 7 years. For the 2015 inventory,...

  16. Forests of Iowa, 2015

    Science.gov (United States)

    Mark D. Nelson; Matt Brewer; Dacia M. Meneguzzo; Kathryne. Clark

    2016-01-01

    This resource update provides an overview of forest resources in Iowa based on inventories conducted by the U.S. Forest Service, Forest Inventory and Analysis (FIA) program at the Northern Research Station in cooperation with the Iowa Department of Natural Resources. Estimates are based on field data collected using the FIA annualized sample design and are updated...

  17. Forests of Nebraska, 2014

    Science.gov (United States)

    Dacia M. Meneguzzo; Susan J. Crocker

    2015-01-01

    This resource update provides an overview of forest resource attributes for Nebraska based on annual inventories conducted by the Forest Inventory and Analysis (FIA) Program of the Northern Research Station (NRS), U.S. Forest Service. The estimates presented in this update are based on field data collected in 2010-2014 with comparisons made to data collected from 2005-...

  18. Forests of Kansas, 2016

    Science.gov (United States)

    Dacia M. Meneguzzo

    2017-01-01

    This resource update provides an overview of forest resources in Kansas based on inventories conducted by the U.S. Forest Service, Forest Inventory and Analysis (FIA) program of the Northern Research Station. For annual inventory years 2001-2013, the sample length was equal to 5 years. Beginning in 2014, the cycle length was changed to 7 years. For the 2016 inventory,...

  19. Forests of Nebraska, 2015

    Science.gov (United States)

    Dacia M. Meneguzzo

    2016-01-01

    This resource update provides an overview of forest resources in Nebraska based on inventories conducted by the U.S. Forest Service, Forest Inventory and Analysis (FIA) program of the Northern Research Station. For annual inventory years 2001-2013, the sample length was equal to 5 years. Beginning in 2014, the cycle length was changed to 7 years. For the 2015 inventory...

  20. Forest resources and conditions

    Science.gov (United States)

    William H. McWilliams; Linda S. Heath; Gordon C. Reese; Thomas L. Schmidt

    2000-01-01

    The forests of the northern United States support a rich mix of floral and faunal communities that provide inestimable benefits to society. Today's forests face a range of biotic and abiotic stressors, not the least of which may be environmental change. This chapter reviews the compositional traits of presettlement forests and traces the major land use patterns...