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Sample records for conditions nelson forest

  1. Nelson syndrome: definition and management.

    PubMed

    Barber, T M; Adams, E; Wass, J A H

    2014-01-01

    Nelson syndrome is an important complication of treatment with total bilateral adrenalectomy (TBA) for patients with refractory Cushing's disease. Although early cases of Nelson syndrome often presented with the clinical features of large sellar masses, the modern face of Nelson syndrome has changed primarily due to earlier detection (with highly resolved magnetic resonance imaging (MRI) and sensitive ACTH assays) and greater awareness of the condition, resulting in reduced morbidity and mortality. Although lack of administration of neoadjuvant pituitary radiotherapy post-TBA surgery may predict future development of Nelson syndrome, other predictive factors remain controversial. Therefore, Nelson syndrome should be screened for closely and long-term in all patients with a history of Cushing's disease and TBA. The diagnosis of Nelson syndrome remains controversial, and the pathogenesis of this condition is incompletely understood. Current hypotheses include the "released negative feedback" mechansism (residual pituitary corticotropinoma cells are "released" from the negative feedback effects of cortisol following TBA), and the "aggressive corticotropinoma" mechanism (Nelson syndrome is most likely to develop in those patients with refractory treatments - including TBA - for an underlying aggressive corticotropinoma). Effective management of Nelson syndrome with pituitary surgery and radiotherapy is often a challenge. Other therapies (such as Gamma Knife surgery and temozolomide) play an important role and merit further research into their efficacy and placement in the management pathway of Nelson syndrome. PMID:25248597

  2. Marilyn Nelson: Poetic Justice

    ERIC Educational Resources Information Center

    Pierpont, Katherine

    2006-01-01

    This article features some of the books written by Marilyn Nelson. Here, the author discusses how she has written a children's book of poetry about lynching, entitled "A Wreath for Emmitt Till." The author discusses how her books for children honor and memorialize history-changing African Americans. Among other things, the author discusses some of…

  3. Nelson Textbook of Pediatrics.

    PubMed

    Pomerance, Herbert H

    1997-03-01

    The dedication of this volume states:To the physicians and nurses who care for children in many different circumstances throughout the world and who, by their efforts and commitment, make the world a better place for children.I have used the Nelson Textbook of Pediatrics since its third edition. It remains a source of amazement to me, as I witness the evolution of the book and of the knowledge that dictates its scope. From the days when a textbook was written by 1 or 2 authors, we have progressed to the point where this would be impossible. Three editors preside over this volume; they are also counted among the 212 contributors that lend special expertise to the work, continuing the volume as one of the traditions of pediatrics.The tremendous and rapid explosion in the amount of knowledge in pediatrics made a revision of the total material and even of.

  4. Decline of forest interior conditions in the conterminous United States.

    PubMed

    Riitters, Kurt H; Wickham, James D

    2012-01-01

    Forest fragmentation threatens the sustainability of forest interior environments, thereby endangering subordinate ecological attributes and functions. We analyzed the spatial patterns of forest loss and gain for the conterminous United States from 2001 to 2006 to determine whether forest interior environments were maintained at five spatial scales. A 1.1% net loss of total forest area translated to net losses of 3.2% to 10.5% of forest interior area over spatial scales of 4.41 ha to 5,310 ha. At the 65.6-ha scale, the reduction of forest interior area was 50,000 km²--almost double the net loss of total forest area. The pervasive discrepancy between total forest loss and forest interior loss indicates a widespread shift of the extant forest to more fragmented conditions, even in regions exhibiting small net changes in extant forest area. In the conterminous United States, trends in total forest area underestimate threats to forest from forest fragmentation.

  5. Nelson River and Hudson Bay

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Rivers that empty into large bodies of water can have a significant impact on the thawing of nearshore winter ice. This true-color Moderate Resolution Imaging Spectroradiometer (MODIS) image from May 18, 2001, shows the Nelson River emptying spring runoff from the Manitoba province to the south into the southwestern corner of Canada's Hudson Bay. The warmer waters from more southern latitudes hasten melting of ice near the shore, though some still remained, perhaps because in shallow coastal waters, the ice could have been anchored to the bottom. High volumes of sediment in the runoff turned the inflow brown, and the rim of the retreating ice has taken on a dirty appearance even far to the east of the river's entrance into the Bay. The sediment would have further hastened the melting of the ice because its darker color would have absorbed more solar radiation than cleaner, whiter ice. Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

  6. ForWarn Forest Disturbance Change Detection System Provides a Weekly Snapshot of US Forest Conditions to Aid Forest Managers

    NASA Astrophysics Data System (ADS)

    Hargrove, W. W.; Spruce, J.; Kumar, J.; Hoffman, F. M.

    2012-12-01

    The Eastern Forest Environmental Threat Assessment Center and Western Wildland Environmental Assessment Center of the USDA Forest Service have collaborated with NASA Stennis Space Center to develop ForWarn, a forest monitoring tool that uses MODIS satellite imagery to produce weekly snapshots of vegetation conditions across the lower 48 United States. Forest and natural resource managers can use ForWarn to rapidly detect, identify, and respond to unexpected changes in the nation's forests caused by insects, diseases, wildfires, severe weather, or other natural or human-caused events. ForWarn detects most types of forest disturbances, including insects, disease, wildfires, frost and ice damage, tornadoes, hurricanes, blowdowns, harvest, urbanization, and landslides. It also detects drought, flood, and temperature effects, and shows early and delayed seasonal vegetation development. Operating continuously since January 2010, results show ForWarn to be a robust and highly capable tool for detecting changes in forest conditions. To help forest and natural resource managers rapidly detect, identify, and respond to unexpected changes in the nation's forests, ForWarn produces sets of national maps showing potential forest disturbances at 231m resolution every 8 days, and posts the results to the web for examination. ForWarn compares current greenness with the "normal," historically seen greenness that would be expected for healthy vegetation for a specific location and time of the year, and then identifies areas appearing less green than expected to provide a strategic national overview of potential forest disturbances that can be used to direct ground and aircraft efforts. In addition to forests, ForWarn also tracks potential disturbances in rangeland vegetation and agriculural crops. ForWarn is the first national-scale system of its kind based on remote sensing developed specifically for forest disturbances. The ForWarn system had an official unveiling and rollout in

  7. Air pollution, forest condition and forest decline in Southern Europe: an overview.

    PubMed

    Bussotti, F; Ferretti, M

    1998-01-01

    Over the last decades much of the work on the impact of air pollution on forests in Europe has concentrated on central and northern countries. The southern part of Europe has received far less attention, although air pollutants-especially the photochemical ones-can reach concentrations likely to have adverse effects on forest vegetation. Although international forest condition surveys present serious problems where data consistency is concerned, they reveal considerable year-by-year species-specific fluctuations rather than a large-scale forest decline. Cases of obvious decline related to environmental factors are well circumscribed: (1) the deterioration of some coastal forests due to the action of polluted seaspray; (2) the deterioration of reforestation projects, especially conifers, mainly due to the poor ecological compatibility between species and site; and (3) the decline of deciduous oaks in southern Italy and of evergreen oaks in the Iberian peninsula apparently due to the interaction of climate stresses and pests and diseases. However, besides obvious deterioration, changes in environmental factors can provoke situations of more subtle stress. The most sensitive stands are Mediterranean conifer forests and mesophile forests of the Mediterranean-montane plane growing at the edges of the natural ecological distribution. Evergreen sclerophyllous forests appear less sensitive to variations in climatic parameters, since they can adapt quite well to both drought and the action of UV-B rays. Several experiments were carried out to test the sensitivity of Mediterranean forest species to air pollutants. Most of those experiments used seedlings of different species treated with pollutant concentrations too high to be realistic, so it is difficult to derive adequate information on the response of adult trees in field conditions. Ozone has been proved to cause foliar injury in a variety of native forest species in different Southern European countries, while the

  8. Comparing Burned and Unburned Forest Conditions Using Simulated Rill Experiments

    NASA Astrophysics Data System (ADS)

    Robichaud, P. R.; Brown, R. E.; Wagenbrenner, J. W.

    2007-12-01

    Despite the dominance of concentrated flow or rill erosion in the erosion processes in disturbed forests, few studies have quantified the effects of different types of forest disturbance on rill erosion. This study quantified the effects of four forest conditions--natural (recently undisturbed), low soil burn severity, high soil burn severity, and skid trails--on rill runoff quantity, runoff velocity, and rill erosion. Simulated rill experiments were conducted at sites in eastern Oregon (Tower Fire) and in northern Washington (North 25 Fire) on forested slopes with granitic and volcanic soils, respectively. The natural and skid trail conditions were established near each burned area in unburned forest. For each rill experiment, concentrated flow was applied at the top of the plot through an energy dissipater at five inflow rates for 12 min each. Runoff was sampled every 2 min and runoff volume and sediment concentration were determined for each sample. The runoff velocity was measured using a dyed calcium chloride solution and two conductivity probes placed a known distance apart. Runoff volume, runoff velocities, and sediment concentrations increased with increasing levels of disturbance. The natural plots had very low runoff rates and sediment concentrations at both the Tower and North 25 sites. The low soil burn severity plots had greater responses than the natural plots, but the responses in the two sites were different as a result of variability in effect of burning and differences in time between burning and the rill experiments. The high soil burn severity and the skid trail plots had the highest runoff ratios, runoff velocities, and sediment concentrations and the responses were similar at both sites. These results suggest that any differences in responses related to soil type or other site factors were masked by the increase in response resulting from the high levels of disturbance.

  9. 78 FR 75205 - Death of Nelson Mandela

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-10

    .... (Presidential Sig.) [FR Doc. 2013-29662 Filed 12-9-13; 11:15 am] Billing code 3295-F4 .... While we mourn his loss, we will forever honor Nelson Mandela's memory. He left behind a South Africa that is free and at peace with itself--a close friend and partner of the United States. And his...

  10. Using Modis Imagery to Track Changes in Forest Condition

    NASA Astrophysics Data System (ADS)

    Chastain, R. A.

    2011-12-01

    The objective of the Real-Time Forest Disturbance (RTFD) project is to provide timely information regarding changes in forest conditions to assist the digital aerial sketch-mapping community in flight mission planning. To this end, a digital change detection methodology has been developed and implemented over the conterminous 48 U.S. states (CONUS) in 2008, 2009, and 2010 to track forest disturbances in near real-time (updated every 8 days). The RTFD approach uses MODIS satellite imagery, which provides daily observations to track developing disturbances that may also be ephemeral in nature. Also, the spectral grain of MODIS data permits the calculation of spectral indices, which the RTFD approach uses to characterize changes in forest condition. Baseline image data used in the RTFD method are produced using MODIS data composited from five years prior to the current growing season. In 2011, an additional 3-year baseline has been used in the change detection process. The RTFD approach has detected and tracked numerous defoliation events in the eastern deciduous biome, decline and mortality associated with beetle activity in the western coniferous biome, and forest damage associated with severe weather events. A quantitative retrospective assessment of 2010 RTFD results was performed to identify potential modifications to the analytical logic of the RTFD approach in order to improve detection efficiency. This assessment was performed within six study areas wherein forest disturbances occurred during 2010. Various methodological alterations were assessed within these study areas; principally, the use of different vegetation indices and alterations in baseline definition. Two-date Landsat change detection results acted as reference data to which RTFD results were compared. Differences in levels of agreement between various RTFD results and Landsat results were evaluated for significance using McNemar's test. The findings of this retrospective assessment indicate that a

  11. Decline of forest interior conditions in the conterminous United States

    EPA Science Inventory

    Forest fragmentation threatens the sustainability of forest interior environments, thereby endangering subordinate ecological attributes and functions. We analyzed the spatial patterns of forest disturbance and recovery for the conterminous United States from 2001 to 2006 to det...

  12. Thomas Eshelby (1769-1811), Nelson's Surgeon.

    PubMed

    Khan, S K; Saeed, I; Brinsden, M D

    2016-08-01

    Horatio Nelson is an icon of British naval history. His above-elbow amputation by Thomas Eshelby remains one of the most famous surgical procedures ever performed. Yet the surgeon himself remains relatively obscure and uncelebrated. We present a vignette of this young Yorkshireman and reflect on his life and times. Eshelby was a competent and conscientious surgeon and was certainly held in high regard by Nelson. Quite a few documents pertaining to his tour of duty in the Mediterranean and to his later appointment at Plymouth have been archived. These shed valuable light on his professional life, betraying his clinical acumen, his conscientious and pragmatic nature and his demeanour toward both his peers and his superiors. Eshelby was also the patriarch of an enterprising family including three generations of surgeons and others with eponymous discoveries in the fields of geography and science.

  13. Modelling Associations between Public Understanding, Engagement and Forest Conditions in the Inland Northwest, USA

    PubMed Central

    Hartter, Joel; Stevens, Forrest R.; Hamilton, Lawrence C.; Congalton, Russell G.; Ducey, Mark J.; Oester, Paul T.

    2015-01-01

    Opinions about public lands and the actions of private non-industrial forest owners in the western United States play important roles in forested landscape management as both public and private forests face increasing risks from large wildfires, pests and disease. This work presents the responses from two surveys, a random-sample telephone survey of more than 1500 residents and a mail survey targeting owners of parcels with 10 or more acres of forest. These surveys were conducted in three counties (Wallowa, Union, and Baker) in northeast Oregon, USA. We analyze these survey data using structural equation models in order to assess how individual characteristics and understanding of forest management issues affect perceptions about forest conditions and risks associated with declining forest health on public lands. We test whether forest understanding is informed by background, beliefs, and experiences, and whether as an intervening variable it is associated with views about forest conditions on publicly managed forests. Individual background characteristics such as age, gender and county of residence have significant direct or indirect effects on our measurement of understanding. Controlling for background factors, we found that forest owners with higher self-assessed understanding, and more education about forest management, tend to hold more pessimistic views about forest conditions. Based on our results we argue that self-assessed understanding, interest in learning, and willingness to engage in extension activities together have leverage to affect perceptions about the risks posed by declining forest conditions on public lands, influence land owner actions, and affect support for public policies. These results also have broader implications for management of forested landscapes on public and private lands amidst changing demographics in rural communities across the Inland Northwest where migration may significantly alter the composition of forest owner goals

  14. Modelling associations between public understanding, engagement and forest conditions in the Inland Northwest, USA.

    PubMed

    Hartter, Joel; Stevens, Forrest R; Hamilton, Lawrence C; Congalton, Russell G; Ducey, Mark J; Oester, Paul T

    2015-01-01

    Opinions about public lands and the actions of private non-industrial forest owners in the western United States play important roles in forested landscape management as both public and private forests face increasing risks from large wildfires, pests and disease. This work presents the responses from two surveys, a random-sample telephone survey of more than 1500 residents and a mail survey targeting owners of parcels with 10 or more acres of forest. These surveys were conducted in three counties (Wallowa, Union, and Baker) in northeast Oregon, USA. We analyze these survey data using structural equation models in order to assess how individual characteristics and understanding of forest management issues affect perceptions about forest conditions and risks associated with declining forest health on public lands. We test whether forest understanding is informed by background, beliefs, and experiences, and whether as an intervening variable it is associated with views about forest conditions on publicly managed forests. Individual background characteristics such as age, gender and county of residence have significant direct or indirect effects on our measurement of understanding. Controlling for background factors, we found that forest owners with higher self-assessed understanding, and more education about forest management, tend to hold more pessimistic views about forest conditions. Based on our results we argue that self-assessed understanding, interest in learning, and willingness to engage in extension activities together have leverage to affect perceptions about the risks posed by declining forest conditions on public lands, influence land owner actions, and affect support for public policies. These results also have broader implications for management of forested landscapes on public and private lands amidst changing demographics in rural communities across the Inland Northwest where migration may significantly alter the composition of forest owner goals

  15. Development history and bibliography of the US Forest Service crown-condition indicator for forest health monitoring.

    PubMed

    Randolph, KaDonna C

    2013-06-01

    Comprehensive assessment of individual-tree crown condition by the US Department of Agriculture, Forest Service, Forest Inventory and Analysis (FIA) Program has its origins in the concerns about widespread forest decline in Europe and North America that developed in the late 1970s and early 1980s. Programs such as the US National Acid Precipitation Assessment Program, US National Vegetation Survey, Canadian Acid Rain National Early Warning System, and joint US-Canadian North American Sugar Maple Decline Project laid the groundwork for the development of the US Forest Service crown-condition indicator. The crown-condition assessment protocols were selected and refined through literature review, peer review, and field studies in several different forest types during the late 1980s and early 1990s. Between 1980 and 2011, 126 publications relating specifically to the crown-condition indicator were added to the literature. The majority of the articles were published by the US Department of Agriculture, Forest Service or other State or Federal government agency, and more than half were published after 2004.

  16. Condition and fate of logged forests in the Brazilian Amazon.

    PubMed

    Asner, Gregory P; Broadbent, Eben N; Oliveira, Paulo J C; Keller, Michael; Knapp, David E; Silva, José N M

    2006-08-22

    The long-term viability of a forest industry in the Amazon region of Brazil depends on the maintenance of adequate timber volume and growth in healthy forests. Using extensive high-resolution satellite analyses, we studied the forest damage caused by recent logging operations and the likelihood that logged forests would be cleared within 4 years after timber harvest. Across 2,030,637 km2 of the Brazilian Amazon from 1999 to 2004, at least 76% of all harvest practices resulted in high levels of canopy damage sufficient to leave forests susceptible to drought and fire. We found that 16+/-1% of selectively logged areas were deforested within 1 year of logging, with a subsequent annual deforestation rate of 5.4% for 4 years after timber harvests. Nearly all logging occurred within 25 km of main roads, and within that area, the probability of deforestation for a logged forest was up to four times greater than for unlogged forests. In combination, our results show that logging in the Brazilian Amazon is dominated by highly damaging operations, often followed rapidly by deforestation decades before forests can recover sufficiently to produce timber for a second harvest. Under the management regimes in effect at the time of our study in the Brazilian Amazon, selective logging would not be sustained.

  17. 4. Historic American Buildings Survey, Nelson E. Baldwin, Photographer April ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Historic American Buildings Survey, Nelson E. Baldwin, Photographer April 30, 1936, VIEW-OLD KITCHEN FIREPLACE AND OVEN, RICE HOMESTEAD, RICEVILLE, N.Y. - Rice Homestead, Route 30, Mayfield, Fulton County, NY

  18. 1. Historic American Buildings Survey, Nelson E. Baldwin, Photographer April ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey, Nelson E. Baldwin, Photographer April 30, 1937, VIEW-FRONT ELEVATION AND SIDE, RICE HOMESTEAD, RICEVILLE, N.Y. - Rice Homestead, Route 30, Mayfield, Fulton County, NY

  19. 2. Historic American Buildings Survey, Nelson E. Baldwin, Photographer April ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey, Nelson E. Baldwin, Photographer April 30, 1936, VIEW-REAR AND SIDE ELEVATIONS, RICE HOMESTEAD, RICEVILLE, N Y. - Rice Homestead, Route 30, Mayfield, Fulton County, NY

  20. 2. Historic American Buildings Survey, Nelson E. Baldwin, Photographer April ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey, Nelson E. Baldwin, Photographer April 7, 1937, VIEW-FRONT AND SIDE ELEVATION ANSON PRATT HOUSE-NEW CONCORD, N.Y. - Anson Pratt House, New Concord, Columbia County, NY

  1. 5. Historic American Buildings Survey, Nelson E. Baldwin, Photographer April ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Historic American Buildings Survey, Nelson E. Baldwin, Photographer April 7, 1937, VIEW-MANTEL IN EAST ROOM-FIRST FLOOR ANSON PRATT HOUSE, NEW CONCORD, N.Y. - Anson Pratt House, New Concord, Columbia County, NY

  2. RIPARIAN FOREST INDICATORS OF POTENTIAL FUTURE STREAM CONDITION

    EPA Science Inventory

    Large wood in streams can play an extraordinarily important role in influencing the physical structure of streams and in providing habitat for aquatic organisms. Since wood is continually lost from streams, predicting the future input of wood to streams from riparian forests is c...

  3. David Nelson, MD, MPH | Division of Cancer Prevention

    Cancer.gov

    Dr. David E Nelson is the Director of the Cancer Prevention Fellowship Program (CPFP) Branch in the National Cancer Institute's Division of Cancer Prevention. The CPFP is an internationally renowned postdoctoral program designed to train early career scientific researchers and leaders in the field of cancer prevention. Dr. Nelson came to the CPFP in 2008 after working at the Centers for Disease Control and Prevention in Atlanta for many years. |

  4. BIRD COMMUNITIES AND HABITAT AS ECOLOGICAL INDICATORS OF FOREST CONDITION IN REGIONAL MONITORING

    EPA Science Inventory

    Ecological indicators for long-term monitoring programs are needed to detect and assess changing environmental conditions, We developed and tested community-level environmental indicators for monitoring forest bird populations and associated habitat. We surveyed 197 sampling plo...

  5. Regression tree modeling of forest NPP using site conditions and climate variables across eastern USA

    NASA Astrophysics Data System (ADS)

    Kwon, Y.

    2013-12-01

    As evidence of global warming continue to increase, being able to predict forest response to climate changes, such as expected rise of temperature and precipitation, will be vital for maintaining the sustainability and productivity of forests. To map forest species redistribution by climate change scenario has been successful, however, most species redistribution maps lack mechanistic understanding to explain why trees grow under the novel conditions of chaining climate. Distributional map is only capable of predicting under the equilibrium assumption that the communities would exist following a prolonged period under the new climate. In this context, forest NPP as a surrogate for growth rate, the most important facet that determines stand dynamics, can lead to valid prediction on the transition stage to new vegetation-climate equilibrium as it represents changes in structure of forest reflecting site conditions and climate factors. The objective of this study is to develop forest growth map using regression tree analysis by extracting large-scale non-linear structures from both field-based FIA and remotely sensed MODIS data set. The major issue addressed in this approach is non-linear spatial patterns of forest attributes. Forest inventory data showed complex spatial patterns that reflect environmental states and processes that originate at different spatial scales. At broad scales, non-linear spatial trends in forest attributes and mixture of continuous and discrete types of environmental variables make traditional statistical (multivariate regression) and geostatistical (kriging) models inefficient. It calls into question some traditional underlying assumptions of spatial trends that uncritically accepted in forest data. To solve the controversy surrounding the suitability of forest data, regression tree analysis are performed using Software See5 and Cubist. Four publicly available data sets were obtained: First, field-based Forest Inventory and Analysis (USDA

  6. Measurements of aerosol chemical composition in boreal forest summer conditions

    NASA Astrophysics Data System (ADS)

    ńijälä, M.; Junninen, H.; Ehn, M.; Petäjä, T.; Vogel, A.; Hoffmann, T.; Corrigan, A.; Russell, L.; Makkonen, U.; Virkkula, A.; Mäntykenttä, J.; Kulmala, M.; Worsnop, D.

    2012-04-01

    Boreal forests are an important biome, covering vast areas of the northern hemisphere and affecting the global climate change via various feedbacks [1]. Despite having relatively few anthropogenic primary aerosol sources, they always contain a non-negligible aerosol population [2]. This study describes aerosol chemical composition measurements using Aerodyne Aerosol Mass Spectrometer (C-ToF AMS, [3]), carried out at a boreal forest area in Hyytiälä, Southern Finland. The site, Helsinki University SMEAR II measurement station [4], is situated at a homogeneous Scots pine (Pinus sylvestris) forest stand. In addition to the station's permanent aerosol, gas phase and meteorological instruments, during the HUMPPA (Hyytiälä United Measurements of Photochemistry and Particles in Air) campaign in July 2010, a very comprehensive set of atmospheric chemistry measurement instrumentation was provided by the Max Planck Institute for chemistry, Johannes Gutenberg-University, University of California and the Finnish Meteorological institute. In this study aerosol chemical composition measurements from the campaign are presented. The dominant aerosol chemical species during the campaign were the organics, although periods with elevated amounts of particulate sulfates were also seen. The overall AMS measured particle mass concentrations varied from near zero to 27 μg/m observed during a forest fire smoke episode. The AMS measured aerosol mass loadings were found to agree well with DMPS derived mass concentrations (r2=0.998). The AMS data was also compared with three other aerosol instruments. The Marga instrument [5] was used to provide a quantitative semi-online measurement of inorganic chemical compounds in particle phase. Fourier Transform Infrared Spectroscopy (FTIR) analysis was performed on daily filter samples, enabling the identification and quantification of organic aerosol subspecies. Finally an Atmospheric Pressure Chemical Ionization Ion Trap Mass Spectrometer (APCI

  7. 7 CFR 1.620 - What supporting information must the Forest Service provide with its preliminary conditions?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false What supporting information must the Forest Service... § 1.620 What supporting information must the Forest Service provide with its preliminary conditions? (a) Supporting information. (1) When the Forest Service files preliminary conditions with FERC,...

  8. Conditional cooperation and costly monitoring explain success in forest commons management.

    PubMed

    Rustagi, Devesh; Engel, Stefanie; Kosfeld, Michael

    2010-11-12

    Recent evidence suggests that prosocial behaviors like conditional cooperation and costly norm enforcement can stabilize large-scale cooperation for commons management. However, field evidence on the extent to which variation in these behaviors among actual commons users accounts for natural commons outcomes is altogether missing. Here, we combine experimental measures of conditional cooperation and survey measures on costly monitoring among 49 forest user groups in Ethiopia with measures of natural forest commons outcomes to show that (i) groups vary in conditional cooperator share, (ii) groups with larger conditional cooperator share are more successful in forest commons management, and (iii) costly monitoring is a key instrument with which conditional cooperators enforce cooperation. Our findings are consistent with models of gene-culture coevolution on human cooperation and provide external validity to laboratory experiments on social dilemmas.

  9. Effect of different spatial resolution of satellite image to observe the forest condition using satellite image and National Forest Inventory data

    NASA Astrophysics Data System (ADS)

    Kajisa, T.; Mizoue, N.; Yoshida, S.

    2010-12-01

    One of the most substantial needs in forest management planning is information about the condition of the forest. Strategic decisions concerning timber policies, decisions about timing and spatial extent of forest operations, and operational decisions such as work plans are all examples where accurate information of the forest conditions are required. Landsat has played the important role for land cover observation in the past, but, got a serious problem. Currently, many kinds of satellite image are available to monitor land cover. So, the utility of different types of satellite image have to be evaluated for land cover monitoring. On the other hands, in Japan, National Forest Inventory (NFI) has been conducted since 1999 with the aim of understanding the state and dynamics of various aspects in forests such as wood production and biodiversity throughout the country. However, few studies have been conducted to combine the satellite image and NFI data. Therefore, the objective of this study was to evaluate the effect of different spatial resolution of satellite image to observe the forest condition (forest/non-forest, forest types, forest stand volume) using satellite image and NFI data.

  10. U.S. Rep. Bill Nelson of Florida during medical tests at JSC's Clinic

    NASA Technical Reports Server (NTRS)

    1985-01-01

    U.S. Rep. Bill Nelson of Florida during medical tests at JSC's Clinic. Photos include Rep. Nelson talking to Sharon Briceno (center) and Betty Lord before the tests begin. The congressman's torso bears a number of sensors for the testing (40835); Portrait view of Rep. Nelson with sensors attached to his chest (40836); Rep. Nelson gets some assistance from nurses at the clinic as he prepares to participate in medical tests. Help is provided by Betty Lord, right, and Sharon Briceno (40837); Rep. Nelson is being assisted to don 'halo' device for tests (40838); Rep. Nelson runs in place on a treadmill device (40839).

  11. Influence of Vegetation and Management Conditions of Forest Cathcments on Their Runoff Characteristics

    NASA Astrophysics Data System (ADS)

    Chikamori, H.

    2007-12-01

    There is rising concern that devastation of planted conifer forests due to poor management might change runoff characteristics and provoke severer flood disasters in Japan. Planted conifer forests in Japan were planted from 1960s to 1970s as a countermeasure to building materials shortage. Domestic forestry products, however, lost out in the price competition with imported products after 1970s, so that forestry has stagnated in Japan, which causes the shortage of forestry workers to maintain planted forests. In this study, runoff variations for the same rainfall pattern observed at neighboring catchments with different conditions were compared so that influence of vegetation and management conditions of forest cathcments on their runoff characteristics was examined. Besides, a Long-and-Short Term (LST) model was calibrated for each of the objective catchments to know the difference in hydrological components as surface flow, subsurface flow, groundwater flow, infiltration and percolation. In three observation sites, eleven catchments were selected as objectives. The areas of the catchments vary from 0.17 to 36 ha. First, runoff characteristics between conifer and broadleaf forests was compared. The result clearly showed that total runoff depth and peak runoff for storm events were both larger in conifer forests than in the broadleaf catchments, and that total infiltration was smaller in conifer than in broadleaf catchments. The result supports the fact that natural forests are generally considered to have functions of water retention and flood control. Second, runoff characteristics between well and poorly managed planted conifer forests was compared. The result, however, did not show the clear difference. It was difficult to find correlation between forest management condition of catchments and total amount of each hydrological process during some storm events, so that the existence of forest management impact on runoff characteristics could not be identified only

  12. Modelling the Meteorological Forest Fire Niche in Heterogeneous Pyrologic Conditions

    PubMed Central

    De Angelis, Antonella; Ricotta, Carlo; Conedera, Marco; Pezzatti, Gianni Boris

    2015-01-01

    Fire regimes are strongly related to weather conditions that directly and indirectly influence fire ignition and propagation. Identifying the most important meteorological fire drivers is thus fundamental for daily fire risk forecasting. In this context, several fire weather indices have been developed focussing mainly on fire-related local weather conditions and fuel characteristics. The specificity of the conditions for which fire danger indices are developed makes its direct transfer and applicability problematic in different areas or with other fuel types. In this paper we used the low-to-intermediate fire-prone region of Canton Ticino as a case study to develop a new daily fire danger index by implementing a niche modelling approach (Maxent). In order to identify the most suitable weather conditions for fires, different combinations of input variables were tested (meteorological variables, existing fire danger indices or a combination of both). Our findings demonstrate that such combinations of input variables increase the predictive power of the resulting index and surprisingly even using meteorological variables only allows similar or better performances than using the complex Canadian Fire Weather Index (FWI). Furthermore, the niche modelling approach based on Maxent resulted in slightly improved model performance and in a reduced number of selected variables with respect to the classical logistic approach. Factors influencing final model robustness were the number of fire events considered and the specificity of the meteorological conditions leading to fire ignition. PMID:25679957

  13. Modelling the meteorological forest fire niche in heterogeneous pyrologic conditions.

    PubMed

    De Angelis, Antonella; Ricotta, Carlo; Conedera, Marco; Pezzatti, Gianni Boris

    2015-01-01

    Fire regimes are strongly related to weather conditions that directly and indirectly influence fire ignition and propagation. Identifying the most important meteorological fire drivers is thus fundamental for daily fire risk forecasting. In this context, several fire weather indices have been developed focussing mainly on fire-related local weather conditions and fuel characteristics. The specificity of the conditions for which fire danger indices are developed makes its direct transfer and applicability problematic in different areas or with other fuel types. In this paper we used the low-to-intermediate fire-prone region of Canton Ticino as a case study to develop a new daily fire danger index by implementing a niche modelling approach (Maxent). In order to identify the most suitable weather conditions for fires, different combinations of input variables were tested (meteorological variables, existing fire danger indices or a combination of both). Our findings demonstrate that such combinations of input variables increase the predictive power of the resulting index and surprisingly even using meteorological variables only allows similar or better performances than using the complex Canadian Fire Weather Index (FWI). Furthermore, the niche modelling approach based on Maxent resulted in slightly improved model performance and in a reduced number of selected variables with respect to the classical logistic approach. Factors influencing final model robustness were the number of fire events considered and the specificity of the meteorological conditions leading to fire ignition.

  14. STS-26 MS Nelson on fixed based (FB) shuttle mission simulator (SMS) middeck

    NASA Technical Reports Server (NTRS)

    1988-01-01

    STS-26 Discovery, Orbiter Vehicle (OV) 103, Mission Specialist (MS) George D. Nelson trains on the middeck of the fixed based (FB) shuttle mission simulator (SMS). Nelson, wearing communications assembly headset, adjusts camera mounting bracket.

  15. STS-26 Mission Specialist Nelson in LES prior to JSC WETF emergency exercises

    NASA Technical Reports Server (NTRS)

    1988-01-01

    STS-26 Discovery, Orbiter Vehicle (OV) 103, Mission Specialist (MS) George D. Nelson, wearing newly designed (navy blue) launch and entry suit (LES), gets some moral support from Aimee Tess Nelson, his sixteen-year-old lifeguard daughter. Nelson was about to participate in a simulation of escape and rescue operations utilizing the crew escape system (CES) pole mode of egress from the Space Shuttle. Nelson is equipped with the LES partial pressure suit and parachute gear.

  16. Ongoing change of site conditions important for sustainable forest management planning

    NASA Astrophysics Data System (ADS)

    Bidló, András; Horváth, Adrienn; Gulyás, Krisztina; Gálos, Borbála

    2016-04-01

    Observed tree mortality of the last decades has shown that the vulnerable forest ecosystems are especially affected by the recurrent, long lasting droughts, heat waves and their consequences. From all site conditions climate is changing the fastest, in this way it can be the largest threatening factor in the 21st century. Beyond climate, soil characteristics are playing an important influencing role. Until now, silvicultural technologies and species preferences of many countries are prescribed by binding regulation based on climate conditions that are assumed to be constant over time. Therefore the aim of our research was to investigate the ongoing and projected change of site conditions that are considered to be of primary importance in terms of tree species selection. For a case study region in Hungary (Keszthely Mountains, near to Lake Balaton) long-term climate tendencies have been determined for the period 1961-2100, as well as a detailed soil sample analysis has been carried out including ~100 sites. Results show a 0.5 degree increase of temperature and a 6-7 % decrease of the precipitation amount for the summer months in the last decades. For the future, significant warming and drying of summers is expected. Decrease of the summer precipitation sum can exceed 25 % until the end of the century, probability of extreme hot days may increase. These tendencies together with the unfavourable soil conditions and biotic damages can be the reason of the ongoing forest dieback. One of the characteristic soil type of the region is rendzina with a thin topsoil layer and an unfavourable water holding capacity. These properties are limiting the amount of available water for plants, especially in case of intense precipitation events. Black pine stands planted on rendzinas after many years of grazing; therefore erosion may have played a significant role. Not only microclimate conditions but also soil types show a large diversity within a relatively small distance. However

  17. John Nelson Darby: His Contributions to Evangelical Christian Higher Education

    ERIC Educational Resources Information Center

    Sutherland, Winston Terrance

    2010-01-01

    The study reported in this article focused on the contributions of John Nelson Derby to biblical hermeneutics and contemporary eschatological thought. Darby continues to exert a great influence on Christianity, particularly conservative evangelical Christianity. This research provides a discussion of Darby's contributions to contemporary…

  18. Philosophical Remarks on Nelson Mandela's Education Legacy

    ERIC Educational Resources Information Center

    Waghid, Yusef

    2014-01-01

    In this article, I reflect on Nelson Mandela's (Madiba, the clan name of Mandela) education legacy. I argue that Madiba's education legacy is constituted by three interrelated aspects: firstly, an education for non-violence guided by deliberation, compassion and reconciliation; secondly, education as responsibility towards the Other; and…

  19. John Nelson Darby: Scholarship that Influenced the Bible College Movement

    ERIC Educational Resources Information Center

    Sutherland, Winston Terrance

    2010-01-01

    The study reported in this article focused on the scholastic life of John Nelson Darby and his contributions to the Bible college movement. Darby continues to exert a great influence on Christianity, particularly conservative evangelical Christianity. This research provides a discussion of the forces that conspired to shape the direction of…

  20. Rep. Bill Nelson rehearses for one of many biomedical experiments

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Rep. Bill Nelson, left, (D.,Florida) familiarizes himself with one of the experiments he is expected to monitor and/or perform during STS 61-C. The protein crystal growth experiment also draws the interest of (from left to right) Vaughn Yost, Charles Walker, and Dr. Larry DeLucas. The four are in JSC's Crew Compartment Trainer.

  1. A Message from Nelson Mandela to the Youth of America.

    ERIC Educational Resources Information Center

    Mandela, Nelson

    1995-01-01

    Presents a message to young people from Nelson Mandela, president of South Africa. Calls for a bridge between the youth of Africa and the United States. Asserts that racial divisions in the United States are major social issues that must be solved. (CFR)

  2. Silenced but Not Silent: The Rhetorical Influence of Nelson Mandela.

    ERIC Educational Resources Information Center

    Boyd, Susy

    In the epicenter of the political strife in South Africa is former African National Congress (ANC) leader Nelson Mandela. The ANC is considered to be the leading source of opposition to white rule in South Africa, and Mandela is one of the most revered and powerful figures to emerge from that organization. Incarcerated for over 25 years on charges…

  3. In Honor of Eyak: The Art of Anna Nelson Harry.

    ERIC Educational Resources Information Center

    Krauss, Michael E., Ed.

    Ten stories, in poem and narrative form, told by Anna Nelson Harry, are presented here. The stories represent a portion of the oral tradition of the Eyak, an Alaskan native nation of which few native speakers remain. An introductory section chronicles the history and decline of the Eyak, the research undertaken to preserve their culture, and the…

  4. Corner Office Interview: SirsiDynix's Rautenstrauch and Nelson

    ERIC Educational Resources Information Center

    Rapp, David; Fialkoff, Francine

    2010-01-01

    This article presents an interview with SirsiDynix CEO Gary M. Rautenstrauch and newly appointed VP of library relations Berit Nelson about some of the issues that have been roiling the ILS world and the company itself, among them the recent consolidation of SirsiDynix's offices, customer service, the state of library budgets, the rise of ebooks…

  5. 2. Historic American Buildings Survey, Nelson E. Baldwin, Photographer, Jan. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Historic American Buildings Survey, Nelson E. Baldwin, Photographer, Jan. 16, 1937, View - Interior Door Opening into Apartment on First Floor, 123 North Pearl St., Albany, N.Y. - Old Homeopathic Hospital (Interiors), 123 North Pearl Street, Albany, Albany County, NY

  6. 4. Historic American Buildings Survey, Nelson E. Baldwin, Photographer, Jan. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Historic American Buildings Survey, Nelson E. Baldwin, Photographer, Jan. 16, 1937, View - Second to Third Floor Stairs Old Homeopathic Hospital, 123 North Pearl St., Albany, N.Y. - Old Homeopathic Hospital (Interiors), 123 North Pearl Street, Albany, Albany County, NY

  7. 1. Historic American Buildings Survey, Nelson E. Baldwin, Photographer, Jan. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey, Nelson E. Baldwin, Photographer, Jan. 16, 1937, View - Stairway from First to Second Floor Old Homeopathic Hospital (Office of the HABS), Albany, N.Y. - Old Homeopathic Hospital (Interiors), 123 North Pearl Street, Albany, Albany County, NY

  8. 3. Historic American Buildings Survey, Nelson E. Baldwin, Photographer, Jan. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Historic American Buildings Survey, Nelson E. Baldwin, Photographer, Jan. 16, 1937, View - Double Doors and Columns in Apartment on First Floor, 123 North Pearl St., Albany, N.Y. - Old Homeopathic Hospital (Interiors), 123 North Pearl Street, Albany, Albany County, NY

  9. A Good Time: A Conversation with C. Michael Nelson

    ERIC Educational Resources Information Center

    Zabel, Robert; Kaff, Marilyn; Teagarden, Jim

    2015-01-01

    C. Michael Nelson began his special education career as a teacher of adolescents with learning and behavior disorders. He has worked as a child psychologist and as a professor with the Department of Special Education and Rehabilitation Counseling at the University of Kentucky. He coordinated the graduate Personnel Preparation Program for Teachers…

  10. Impacts of annual weather conditions on forest productivity

    NASA Astrophysics Data System (ADS)

    Reed, David D.; Jones, Elizabeth A.; Liechty, Hal O.; Mroz, Glenn D.; Jurgensen, Martin F.

    1992-03-01

    The response of four northern deciduous tree species to annual climate variation is quantified at two intensively measured sites in northern Michigan, USA. Response to changes in temperature and moisture differ with the species and is dependent on other site conditions. Relationships identified in these field studies indicate that projected climate changes may have dramatic effects on the productivity of at least some commercially important tree species in the northern United States.

  11. A PROBABILITY SURVEY OF SUCCESSIONAL FOREST COMPOSITION AND CONDITION IN A GREAT RIVER FLOODPLAIN LANDSCAPE

    EPA Science Inventory

    Floodplains within the Great River Ecosystems (GREs) of the central U.S. are composed of dynamic mosaics of successional habitat that (when unmodified) are typically dominated by cottonwood forest (Populus ssp.). GRE riparian habitat condition and successional dynamics are linked...

  12. Matrix Intensification Affects Body and Physiological Condition of Tropical Forest-Dependent Passerines.

    PubMed

    Deikumah, Justus P; McAlpine, Clive A; Maron, Martine

    2015-01-01

    Matrix land-use intensification is a relatively recent and novel landscape change that can have important influences on the biota within adjacent habitat patches. While there are immediate local changes that it brings about, the influences on individual animals occupying adjacent habitats may be less evident initially. High-intensity land use could induce chronic stress in individuals in nearby remnants, leading ultimately to population declines. We investigated how physiological indicators and body condition measures of tropical forest-dependent birds differ between forest adjacent to surface mining sites and that near farmlands at two distances from remnant edge in southwest Ghana. We used mixed effects models of several condition indices including residual body mass and heterophil to lymphocyte (H/L) ratios (an indicator of elevated chronic stress) to explore the effect of matrix intensity on forest-dependent passerines classed as either sedentary area-sensitive habitat specialists or nomadic generalists. Individual birds occupying tropical forest remnants near surface mining sites were in poorer condition, as indicated by lower residual body mass and elevated chronic stress, compared to those in remnants near agricultural lands. The condition of the sedentary forest habitat specialists white-tailed alethe, Alethe diademata and western olive sunbird, Cyanomitra obscura was most negatively affected by high-intensity surface mining land-use adjacent to remnants, whereas generalist species were not affected. Land use intensification may set in train a new trajectory of faunal relaxation beyond that expected based on habitat loss alone. Patterns of individual condition may be useful in identifying habitats where species population declines may occur before faunal relaxation has concluded. PMID:26107179

  13. Matrix Intensification Affects Body and Physiological Condition of Tropical Forest-Dependent Passerines.

    PubMed

    Deikumah, Justus P; McAlpine, Clive A; Maron, Martine

    2015-01-01

    Matrix land-use intensification is a relatively recent and novel landscape change that can have important influences on the biota within adjacent habitat patches. While there are immediate local changes that it brings about, the influences on individual animals occupying adjacent habitats may be less evident initially. High-intensity land use could induce chronic stress in individuals in nearby remnants, leading ultimately to population declines. We investigated how physiological indicators and body condition measures of tropical forest-dependent birds differ between forest adjacent to surface mining sites and that near farmlands at two distances from remnant edge in southwest Ghana. We used mixed effects models of several condition indices including residual body mass and heterophil to lymphocyte (H/L) ratios (an indicator of elevated chronic stress) to explore the effect of matrix intensity on forest-dependent passerines classed as either sedentary area-sensitive habitat specialists or nomadic generalists. Individual birds occupying tropical forest remnants near surface mining sites were in poorer condition, as indicated by lower residual body mass and elevated chronic stress, compared to those in remnants near agricultural lands. The condition of the sedentary forest habitat specialists white-tailed alethe, Alethe diademata and western olive sunbird, Cyanomitra obscura was most negatively affected by high-intensity surface mining land-use adjacent to remnants, whereas generalist species were not affected. Land use intensification may set in train a new trajectory of faunal relaxation beyond that expected based on habitat loss alone. Patterns of individual condition may be useful in identifying habitats where species population declines may occur before faunal relaxation has concluded.

  14. Matrix Intensification Affects Body and Physiological Condition of Tropical Forest-Dependent Passerines

    PubMed Central

    Deikumah, Justus P.; McAlpine, Clive A.; Maron, Martine

    2015-01-01

    Matrix land-use intensification is a relatively recent and novel landscape change that can have important influences on the biota within adjacent habitat patches. While there are immediate local changes that it brings about, the influences on individual animals occupying adjacent habitats may be less evident initially. High-intensity land use could induce chronic stress in individuals in nearby remnants, leading ultimately to population declines. We investigated how physiological indicators and body condition measures of tropical forest-dependent birds differ between forest adjacent to surface mining sites and that near farmlands at two distances from remnant edge in southwest Ghana. We used mixed effects models of several condition indices including residual body mass and heterophil to lymphocyte (H/L) ratios (an indicator of elevated chronic stress) to explore the effect of matrix intensity on forest-dependent passerines classed as either sedentary area-sensitive habitat specialists or nomadic generalists. Individual birds occupying tropical forest remnants near surface mining sites were in poorer condition, as indicated by lower residual body mass and elevated chronic stress, compared to those in remnants near agricultural lands. The condition of the sedentary forest habitat specialists white-tailed alethe, Alethe diademata and western olive sunbird, Cyanomitra obscura was most negatively affected by high-intensity surface mining land-use adjacent to remnants, whereas generalist species were not affected. Land use intensification may set in train a new trajectory of faunal relaxation beyond that expected based on habitat loss alone. Patterns of individual condition may be useful in identifying habitats where species population declines may occur before faunal relaxation has concluded. PMID:26107179

  15. Monitoring the condition of the Canadian forest environment: The relevance of the concept of 'ecological indicators'.

    PubMed

    Kimmins, J P

    1990-11-01

    The Canadian forest environment is characterized by high spatial and temporal variability, especially in the west. Our forests vary according to climate, landform, and surficial geology, and according to the type, intensity, extent of, and the time since the last disturbance. Most Canadian forests have had a history of repeated acute, episodic disturbance from fire, insects, wind, diseases and/or logging, with a frequency of disturbance varying from a few decades to many centuries. These sources of variability have resulted in a complex and continually changing mosaic of forest conditions and stages of successional development.Monitoring the 'quality' of this dynamic forested landscape mosaic is extremely difficult, and in most cases the concept of a relatively simple index of forest ecosystem quality or condition (i.e. an 'ecological indicator') is probably inappropriate. Such ecological indicators are better suited for monitoring chronic anthropogenically induced disturbances that are continuous in their effect (e.g. 'acid rain', heavy metal pollution, air pollution, and the 'greenhouse effect') in ecosystems that, in the absence of such chronic disturbance, exhibit very slow directional change (e.g. lakes, higher order streams and rivers). Monitoring the effects of a chronic anthropogenic disturbance to forest ecosystems to determine if it is resulting in a sustained, directional alteration of environmental 'quality' will require a definition of the expected pattern of episodic disturbance and recovery therefrom (i.e. patterns of secondary succession in the absence of the chronic disturbance). Only when we have such a 'temporal fingerprint' of forest ecosystem condition for 'normal' patterns of disturbance and recovery can we determine if the ecosystem condition is being degraded by chronic human-induced alteration of the environment. Thus, degradation is assessed in terms of deviations from the expected temporal pattern of conditions rather than in terms of an

  16. Monitoring the condition of the Canadian forest environment: The relevance of the concept of 'ecological indicators'.

    PubMed

    Kimmins, J P

    1990-11-01

    The Canadian forest environment is characterized by high spatial and temporal variability, especially in the west. Our forests vary according to climate, landform, and surficial geology, and according to the type, intensity, extent of, and the time since the last disturbance. Most Canadian forests have had a history of repeated acute, episodic disturbance from fire, insects, wind, diseases and/or logging, with a frequency of disturbance varying from a few decades to many centuries. These sources of variability have resulted in a complex and continually changing mosaic of forest conditions and stages of successional development.Monitoring the 'quality' of this dynamic forested landscape mosaic is extremely difficult, and in most cases the concept of a relatively simple index of forest ecosystem quality or condition (i.e. an 'ecological indicator') is probably inappropriate. Such ecological indicators are better suited for monitoring chronic anthropogenically induced disturbances that are continuous in their effect (e.g. 'acid rain', heavy metal pollution, air pollution, and the 'greenhouse effect') in ecosystems that, in the absence of such chronic disturbance, exhibit very slow directional change (e.g. lakes, higher order streams and rivers). Monitoring the effects of a chronic anthropogenic disturbance to forest ecosystems to determine if it is resulting in a sustained, directional alteration of environmental 'quality' will require a definition of the expected pattern of episodic disturbance and recovery therefrom (i.e. patterns of secondary succession in the absence of the chronic disturbance). Only when we have such a 'temporal fingerprint' of forest ecosystem condition for 'normal' patterns of disturbance and recovery can we determine if the ecosystem condition is being degraded by chronic human-induced alteration of the environment. Thus, degradation is assessed in terms of deviations from the expected temporal pattern of conditions rather than in terms of an

  17. Identifying Hydrological Controls in the Lower Nelson River Basin utilizing Stable Water Isotopes

    NASA Astrophysics Data System (ADS)

    Delavau, C. J.; Smith, A. A.; Stadnyk, T.; Koenig, K.

    2012-12-01

    In 2010 a Stable Water Isotope (SWI) Monitoring Network was established within the lower Nelson River Basin (LNRB) (approximately 90,000 km2) in northern Manitoba, Canada, through a joint collaboration between the University of Manitoba and Manitoba Hydro (MH). The monitoring network encompasses over 60 sites where surface waters are regularly sampled, four sites sampling isotopes in precipitation, two sites utilizing drive point piezometers for the isotopic sampling of baseflow waters, and one site collecting evaporatively enriched water samples from an evaporation pan. In addition, two synoptic surveys have been completed in June 2011 and July 2012 to obtain annual snapshots of the monitoring network at a point in time. Currently, over 700 samples have been collected and analyzed. The LNRB contains approximately 9% of the total Nelson River Basin (NRB) drainage area, which encompasses an area of over 1 million km2. A diversion from the Churchill River through the Rat/Burntwood system routes an additional portion of flow into the northwest portion of the LNRB. The LNRB is significant to MH's network as it represents 75% of their power generation potential through six generating stations, thus resulting in a large portion of the basin being regulated. The watershed is topographically flat, therefore the movement and runoff of water, as well as isotopic composition of streamflow, is suspected to be highly impacted by changes in landscape and hydrography. The LNRB is a coniferous and wetland dominated basin, with almost 35% of the land cover composed of coniferous forest and 40% comprised of wetlands and lakes. Interpretation of the LNRB isotope framework shows that the major water sources (rainfall, snowfall, groundwater and surface waters) and rivers are isotopically distinct from one another. The main stem of the Nelson River shows little spatial or temporal variability, with an average δ18O of -10.6‰ and a standard deviation of 0.5‰ throughout the sampling

  18. [Effects of topographical condition and sampling number on the interpolation precision of forest litter carbon density].

    PubMed

    Zhang, Jia-jia; Fu, Wei-jun; Du, Qun; Zhang, Guo-jiang; Jiang, Pei-kun

    2013-08-01

    The territory of Zhejiang Province, East China was grouped into 3 topographical units (plain-coastal area, hill-basin area, and mountain area) to investigate the effects of topographical condition and sampling number on the Kriging interpolation precision of forest litter carbon density in the Province. The forest litter carbon density in the 3 topographical units showed a medium spatial correlation pattern, with the semi-variance nugget/sill ratio value ranged from 28.3% to 72.4%. The Kriging interpolation precision was in the order of plain-coastal area > hill-basin area > mountain area, indicating that the Kriging interpolation precision decreased with the increase of terrain complexity degree. Within the same topographical units, the Kriging interpolation precision improved with increasing sampling number, being most obvious in the mountain area. Therefore, under complicated topographical conditions, greater sampling number was required to achieve a high precision of Kriging interpolation. PMID:24380344

  19. [Effects of atmospheric thermally stratified condition on sensible heat within forest canopy].

    PubMed

    Diao, Yi-Wei; Wang, An-Zhi; Guan, De-Xin; Jin, Chang-Jie; Pei, Tie-Fan

    2010-01-01

    By using Eulerian second-order closure model, this paper studied the source-sink distribution and flux characteristics of sensible heat within forest canopy under atmospheric thermally stratified condition. In the daytime, a notable feature for the atmospheric stratification of forest canopy was the unstable stratification above the canopy and the stable stratification under the canopy. The changes of temperature profile indicated there was a 'hot spot' at about 2/3 of canopy height. The counter-gradient fluxes within the canopy were discovered by modeling the heat flux under weak stable atmospheric condition. Simulations of the diurnal variation of sensible heat flux were consistent with the measurements (R2 = 0.9035, P < 0.01). Adding buoyancy in the sensible heat balance equation could increase the simulation accuracy of inversion model, and improve the simulation capability for heat flux balance.

  20. Associations of Forest Type, Parasitism and Body Condition of Two European Passerines, Fringilla coelebs and Sylvia atricapilla

    PubMed Central

    Lüdtke, Bruntje; Moser, Isabelle; Santiago-Alarcon, Diego; Fischer, Markus; Kalko, Elisabeth KV.; Schaefer, H. Martin; Suarez-Rubio, Marcela; Tschapka, Marco; Renner, Swen C.

    2013-01-01

    Human-induced forest modification can alter parasite-host interactions and might change the persistence of host populations. We captured individuals of two widespread European passerines (Fringilla coelebs and Sylvia atricapilla) in southwestern Germany to disentangle the associations of forest types and parasitism by haemosporidian parasites on the body condition of birds. We compared parasite prevalence and parasite intensity, fluctuating asymmetries, leukocyte numbers, and the heterophil to lymphocyte ratio (H/L-ratio) among individuals from beech, mixed-deciduous and spruce forest stands. Based on the biology of bird species, we expected to find fewer infected individuals in beech or mixed-deciduous than in spruce forest stands. We found the highest parasite prevalence and intensity in beech forests for F. coelebs. Although, we found the highest prevalence in spruce forests for S. atricapilla, the highest intensity was detected in beech forests, partially supporting our hypothesis. Other body condition or health status metrics, such as the heterophil to lymphocyte ratio (H/L-ratio), revealed only slight differences between bird populations inhabiting the three different forest types, with the highest values in spruce for F. coelebs and in mixed-deciduous forests for S. atricapilla. A comparison of parasitized versus non-parasitized individuals suggests that parasite infection increased the immune response of a bird, which was detectable as high H/L-ratio. Higher infections with blood parasites for S. atricapilla in spruce forest indicate that this forest type might be a less suitable habitat than beech and mixed-deciduous forests, whereas beech forests seem to be a suboptimal habitat regarding parasitism for F. coelebs. PMID:24339923

  1. Associations of forest type, parasitism and body condition of two European passerines, Fringilla coelebs and Sylvia atricapilla.

    PubMed

    Lüdtke, Bruntje; Moser, Isabelle; Santiago-Alarcon, Diego; Fischer, Markus; Kalko, Elisabeth K V; Schaefer, H Martin; Suarez-Rubio, Marcela; Tschapka, Marco; Renner, Swen C

    2013-01-01

    Human-induced forest modification can alter parasite-host interactions and might change the persistence of host populations. We captured individuals of two widespread European passerines (Fringilla coelebs and Sylvia atricapilla) in southwestern Germany to disentangle the associations of forest types and parasitism by haemosporidian parasites on the body condition of birds. We compared parasite prevalence and parasite intensity, fluctuating asymmetries, leukocyte numbers, and the heterophil to lymphocyte ratio (H/L-ratio) among individuals from beech, mixed-deciduous and spruce forest stands. Based on the biology of bird species, we expected to find fewer infected individuals in beech or mixed-deciduous than in spruce forest stands. We found the highest parasite prevalence and intensity in beech forests for F. coelebs. Although, we found the highest prevalence in spruce forests for S. atricapilla, the highest intensity was detected in beech forests, partially supporting our hypothesis. Other body condition or health status metrics, such as the heterophil to lymphocyte ratio (H/L-ratio), revealed only slight differences between bird populations inhabiting the three different forest types, with the highest values in spruce for F. coelebs and in mixed-deciduous forests for S. atricapilla. A comparison of parasitized versus non-parasitized individuals suggests that parasite infection increased the immune response of a bird, which was detectable as high H/L-ratio. Higher infections with blood parasites for S. atricapilla in spruce forest indicate that this forest type might be a less suitable habitat than beech and mixed-deciduous forests, whereas beech forests seem to be a suboptimal habitat regarding parasitism for F. coelebs.

  2. Climate phase drives canopy condition in a large semi-arid floodplain forest.

    PubMed

    Wen, Li; Saintilan, Neil

    2015-08-15

    To maintain and restore the ecological integrity of floodplains, allocating water for environmental benefits (i.e. environmental water) is widely practised globally. To efficiently manage the always limited environmental water, there is pressing need to advance our understanding of the ecological response to long-term climate cycles as evidence grows of intensification of extreme climatic events such as severe drought and heat waves. In this study, we assessed the alleviating effects of artificial flooding on drought impact using the canopy condition of the iconic river red gum forests in Australia's Murray Darling Basin (MDB). To achieve this, we jointly analysed spatial-temporal patterns of NDVI response and drought conditions for the period of 2000-2013, during which the MDB experienced an extreme dry-wet cycle. Our results indicated that while NDVI-derived canopy condition was better at the sites receiving environmental water during the dry phases, both watered and unwatered sites displayed great similarity in seasonality and trends. Furthermore, we did not find any significant difference in NDVI response of the canopy between the sites to suggest significant differences in ecosystem stability and resilience, with watered and unwatered sites showing similar responses to the extreme wet conditions as the drought broke. The highly significant relationship between long-term drought index and NDVI anomaly suggest that climate phase is the main forcing driving canopy condition in semi-arid floodplain forests. PMID:26027753

  3. Climate phase drives canopy condition in a large semi-arid floodplain forest.

    PubMed

    Wen, Li; Saintilan, Neil

    2015-08-15

    To maintain and restore the ecological integrity of floodplains, allocating water for environmental benefits (i.e. environmental water) is widely practised globally. To efficiently manage the always limited environmental water, there is pressing need to advance our understanding of the ecological response to long-term climate cycles as evidence grows of intensification of extreme climatic events such as severe drought and heat waves. In this study, we assessed the alleviating effects of artificial flooding on drought impact using the canopy condition of the iconic river red gum forests in Australia's Murray Darling Basin (MDB). To achieve this, we jointly analysed spatial-temporal patterns of NDVI response and drought conditions for the period of 2000-2013, during which the MDB experienced an extreme dry-wet cycle. Our results indicated that while NDVI-derived canopy condition was better at the sites receiving environmental water during the dry phases, both watered and unwatered sites displayed great similarity in seasonality and trends. Furthermore, we did not find any significant difference in NDVI response of the canopy between the sites to suggest significant differences in ecosystem stability and resilience, with watered and unwatered sites showing similar responses to the extreme wet conditions as the drought broke. The highly significant relationship between long-term drought index and NDVI anomaly suggest that climate phase is the main forcing driving canopy condition in semi-arid floodplain forests.

  4. Rep. Bill Nelson during space food and consumables orientation and suit fitting

    NASA Technical Reports Server (NTRS)

    1987-01-01

    Rita Rapp, a flight coordinator, briefs U.S. Rep. Bill Nelson (D.-Florida) on space food during an orientation session in the life sciences laboratory at JSC (27753); Rep. Nelson tries on a glove during a suit fitting session (27754); Rep. Nelson samples a package of re-hydratable fruit in the life sciences laboratory during early STS 61-C training (27755); Rep. Nelson listens to Laura Louviere brief him on hygiene articles soon after reporting to Houston for STS 61-C training. On the table in front of him is a tube marked Palmalive, a tube marked Gillette and various other articles (27756).

  5. Carbon and Nitrogen dynamics in forest soils depending on light conditions and tree species

    NASA Astrophysics Data System (ADS)

    Veselinovic, Bojana; Hager, Herbert

    2013-04-01

    Climate change mitigation actions under the Kyoto Protocol apply among other decreases of CO2-emissions and/or increases of carbon (C) stocks. As soils represent the second biggest C-reservoir on Earth, an exact estimation of the stocks and reliable knowledge on C-dynamics in forest soils is of high importance. Anyhow, here, the accurate GHG-accounting, emission reductions and increase in C stocks is hampered due to lack of reliable data and solid statistical methods for the factors which influence C-sequestration in and its release from these systems. In spite of good progress in the scientific research, these factors are numerous and diverse in their interactions. This work focuses on influence of the economically relevant tree species - Picea abies, Fagus sylvatica and Quercus spp. - and light conditions on forest floor and mineral soil C and N dynamics in forest soils. Spruce monocultures have been widely used management practices in central European forests during the past century. Such stands are in lower altitudes and on heavy and water logged soils unstable and prone to disturbances, especially to windthrows. We hypothesize that windthrow areas loose C & N and that the establishment of the previous nutrient stocks is, if at all, only possible to be reached over the longer periods of time. We research also how the increased OM depletion affects the change of C & N stocks in forest floor vs. mineral soil. Conversion of such secondary spruce monocultures to site adequate beech and oak forests may enable higher stocks allocated predominantly as stable organic carbon and as plant available nitrogen. For this purpose sites at 300-700 m altitude with planosols were chosen in the region of the Northern Alpine Foothills. A false chronosequence approach was used in order to evaluate the impacts of the tree species and change in light conditions on dynamic of C & N in the forest floor and mineral soil, over the period 0-100 (for oak 120 y.) years. The C- and N

  6. Failure Analysis of Main Flame Deflector Nelson Studs

    NASA Technical Reports Server (NTRS)

    Long, Victoria

    2009-01-01

    NASA Structures engineers submitted two Nelson refractory studs from the main flame deflector at Launch Complex (LC) 39 A for analysis when they were observed to be missing a significant amount of material after launch. The damaged stud and an unused comparative stud were analyzed by macroscopic and microscopic examination along with metallographic evaluation of the microstructure. The stud lost material due to a combination of erosion and corrosion. Plain carbon steel readily forms an oxide layer in the coastal launch environment at Kennedy Space Center. The blast during a launch removes this brittle oxide layer, which then forms again post-launch, thereby further removing material. No indications of melting were observed.

  7. Treatment of Acromegaly, Cushing Disease and Nelson Syndrome

    PubMed Central

    Lawrence, John H.; Linfoot, John A.

    1980-01-01

    Since 1957 we have treated more than 429 patients who had pituitary neoplasms, most of which were hormone-secreting tumors. Long-term follow-up in the large group of patients treated for acromegaly shows a median survival of better than 16 years, with improvement over time. The short-term follow-up results in patients with Cushing* disease, Nelson syndrome and chromophobe adenoma are very encouraging. To compare these excellent results with those following surgical procedures, a large study of patients followed for a long period after the operations is needed. ImagesFigure 2.Figure 6. PMID:7415170

  8. Region and site conditions affect phenotypic trait variation in five forest herbs

    NASA Astrophysics Data System (ADS)

    Lemke, Isgard Holle; Kolb, Annette; Diekmann, Martin Reemt

    2012-02-01

    Phenotypic plasticity is the ability of organisms to express different phenotypes under different environmental conditions. It may buffer individuals both against short-term environmental fluctuations and long-term effects of global change. A plastic behaviour in response to changes in the environment may be especially important in species with low migration rates and colonization capacities, such as in many forest plants in present-day fragmented landscapes. We compared the phenotypic trait variation (used as a proxy for the amount of phenotypic plasticity) of five forest herbs (Brachypodium sylvaticum, Circaea lutetiana, Impatiens noli-tangere, Sanicula europaea and Stachys sylvatica) between two regions in Germany that differ in their overall environmental conditions (Bremen in the northwest, Freiburg in the southwest; 5 species × 2 regions × 8-15 populations × 25-50 individuals). In addition, we measured light intensity and important soil parameters (soil pH, moisture, K, P and N) in all populations. We found consistent differences in trait variability between the two regions in several species. In Brachypodium and Stachys both vegetative and reproductive traits were more variable in Freiburg. Similarly, reproductive traits of Impatiens and Sanicula appeared to be more variable in Freiburg, while in both species at least one of the vegetative traits was more variable in Bremen. Mean local environmental conditions also affected trait variation; in most of the species both vegetative and reproductive traits were more variable in sites with higher nutrient contents and higher light availability. Across all traits and both regions, seed or fruit production was most variable. In summary, at least some of the studied forest herbs appear to respond strongly to large-scale environmental differences, showing a higher trait variability in the more southern region. Given the assumption that phenotypic trait variation is positively associated with phenotypic plasticity

  9. Modelling hydrological conditions in the maritime forest region of south-western Nova Scotia

    NASA Astrophysics Data System (ADS)

    Yanni, Shelagh; Keys, Kevin; Meng, Fan-Rui; Yin, Xiwei; Clair, Tom; Arp, Paul A.

    2000-02-01

    Hydrological processes and conditions were quantified for the Mersey River Basin (two basins: one exiting below Mill Falls, and one exiting below George Lake), the Roger's Brook Basin, Moosepit Brook, and for other selected locations at and near Kejimkujik National Park in Nova Scotia, Canada, from 1967 to 1990. Addressed variables included precipitation (rain, snow, fog), air temperature, stream discharge, snowpack accumulations, throughfall, soil and subsoil moisture, soil temperature and soil frost, at a monthly resolution. It was found that monthly per hectare stream discharge was essentially independent of catchment area from <20 km2 to more than 1000 km2. The forest hydrology model ForHyM2 was used to simulate monthly rates of stream discharge, throughfall and snowpack water equivalents for mature forest conditions. These simulations were in good agreement with the historical records once the contributions of fog and mist to the area-wide water budget were taken into account, each on a monthly basis. The resulting simulations establish a hydrologically consistent, continuous, comprehensive and partially verified record for basin-wide outcomes for all major hydrological processes and conditions, be these related to stream discharge, soil moisture, soil temperature, snowpack accumulations, soil frost, throughfall, interception and soil percolation.

  10. Rebuttal to Nelson et al. 'Response to Bodin and Grote regarding postdoctoral recruitment in clinical neuropsychology'.

    PubMed

    Bodin, Doug; Grote, Christopher L

    2016-07-01

    Nelson et al. provided a response to our commentary on the postdoctoral match in clinical neuropsychology. In this brief rebuttal, we will focus on statements from Nelson et al. that we believe are factual inaccuracies or misunderstandings of some of the points we made in our commentary. In addition, we will comment briefly on the proposed guidelines offered in their response.

  11. STS-26 MS Nelson prepares meal at galley on Discovery's middeck

    NASA Technical Reports Server (NTRS)

    1988-01-01

    STS-26 Mission Specialist (MS) George D. Nelson, wearing thermal underwear, positions himself in front of the orbiter galley using the intravehicular activity (IVA) foot restraints and prepares a meal on Discovery's, Orbiter Vehicle (OV) 103's, middeck. Beverage containers are velcroed to the galley shelf as Nelson rehydrates a food package.

  12. 3 CFR 9067 - Proclamation 9067 of December 5, 2013. Death of Nelson Mandela

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Nelson Mandela's memory. He left behind a South Africa that is free and at peace with itself—a close friend and partner of the United States. And his memory will be kept in the hearts of billions who have... memory of Nelson Mandela, by the authority vested in me as President of the United States by...

  13. STS-26 MS Nelson prepares for EVA exercises at JSC's WETF Bldg 29

    NASA Technical Reports Server (NTRS)

    1988-01-01

    STS-26 Discovery, Orbiter Vehicle (OV) 103, Mission Specialist (MS) George D. Nelson, wearing extravehicular mobilty unit (EMU) and communications carrier assembly (CCA), stands on poolside platform while technicians assist him with EMU gloves. Nelson dons EMU for contingency extravehicular activity (EVA) exercises in JSC's Weightless Environment Training Facility (WETF) Bldg 29. Photograph was taken by Keith Meyers of the NEW YORK TIMES.

  14. Practical Application of Electrochemical Nitrate Sensor under Laboratory and Forest Nursery Conditions.

    PubMed

    Caron, William-Olivier; Lamhamedi, Mohammed S; Viens, Jeff; Messaddeq, Younès

    2016-01-01

    The reduction of nitrate leaching to ensure greater protection of groundwater quality has become a global issue. The development of new technologies for more accurate dosing of nitrates helps optimize fertilization programs. This paper presents the practical application of a newly developed electrochemical sensor designed for in situ quantification of nitrate. To our knowledge, this paper is the first to report the use of electrochemical impedance to determine nitrate concentrations in growing media under forest nursery conditions. Using impedance measurements, the sensor has been tested in laboratory and compared to colorimetric measurements of the nitrate. The developed sensor has been used in water-saturated growing medium and showed good correlation to certified methods, even in samples obtained over a multi-ion fertilisation season. A linear and significant relationship was observed between the resistance and the concentration of nitrates (R² = 0.972), for a range of concentrations of nitrates. We also observed stability of the sensor after exposure of one month to the real environmental conditions of the forest nursery. PMID:27483266

  15. Practical Application of Electrochemical Nitrate Sensor under Laboratory and Forest Nursery Conditions

    PubMed Central

    Caron, William-Olivier; Lamhamedi, Mohammed S.; Viens, Jeff; Messaddeq, Younès

    2016-01-01

    The reduction of nitrate leaching to ensure greater protection of groundwater quality has become a global issue. The development of new technologies for more accurate dosing of nitrates helps optimize fertilization programs. This paper presents the practical application of a newly developed electrochemical sensor designed for in situ quantification of nitrate. To our knowledge, this paper is the first to report the use of electrochemical impedance to determine nitrate concentrations in growing media under forest nursery conditions. Using impedance measurements, the sensor has been tested in laboratory and compared to colorimetric measurements of the nitrate. The developed sensor has been used in water-saturated growing medium and showed good correlation to certified methods, even in samples obtained over a multi-ion fertilisation season. A linear and significant relationship was observed between the resistance and the concentration of nitrates (R2 = 0.972), for a range of concentrations of nitrates. We also observed stability of the sensor after exposure of one month to the real environmental conditions of the forest nursery. PMID:27483266

  16. Soil organic carbon of European forest soils: current stock and projections under climate change conditions

    NASA Astrophysics Data System (ADS)

    Caddeo, Antonio; Marras, Serena; Spano, Donatella; Sirca, Costantino

    2016-04-01

    Soil organic carbon (SOC) represents the largest terrestrial carbon pool, and it is subjected to climate change impacts. In Europe, a limited number of studies makes a wide-scale comparison of SOC stock and changes under climate change conditions, and most of them are related to agricultural soils. In this work, the SOC stock of the forested areas of Europe (obtained from the CORINE 2006 Land Use Map) was assessed at 1 km resolution using the agro-ecosystem SOC model CENTURY. The results of the model were compared with independent observational datasets (i.e. LUCAS Topsoil Survey Database). In addition, climate simulations (RCPs 4.5 and 8.5) using the CMCC (Euro-Mediterranean Centre on Climate Change) and the CORDEX dataset were used to estimate the SOC changes of these areas under climate change conditions.

  17. Snowpack Response to Changes in Forest Condition Over Six Years Post Mountain Pine Beetle Attack

    NASA Astrophysics Data System (ADS)

    Winkler, R.; Boon, S.

    2011-12-01

    Since 1994, 17.5 million hectares of lodgepole pine dominated forest in British Columbia have been attacked by mountain pine beetle (MPB). More than 6 million hectares of timber in Alberta are susceptible, as are lodgepole pine stands throughout the western United States. Such extensive forest die-off raises concern regarding increased snow accumulation and ablation rates in affected stands and associated increases in snowmelt generated streamflow. To quantify changes in snow accumulation and ablation post-MPB, forest condition and snow were monitored in an attacked young lodgepole pine stand, a mature mixed species green stand and a clearcut near Mayson Lake in the southern interior of BC. Surveys began in 2006, the year following attack, and continued until 2011, as trees turned from green to red to grey. Forest canopy loss was described by canopy transmittance and litter in and on the snowpack. Canopy transmittance in the attacked stand increased from 27% in fall 2007 to 49% in spring 2011. Canopy transmittance in the mature stand remained constant, averaging 19% across the stand. The greatest canopy loss in the attacked stand occurred in summer 2009 when canopy transmittance increased from 35% to 42%. However, the largest accumulation of litter over a winter was measured in the spring of 2009 when the weight of litter in the snowpack (210 g m-2) was double that in the green stand and ten times the amount collected in 2010, by which time trees were turning grey. At mid-melt 2009, snow surface litter cover in the attacked stand varied from 0% to 54% and averaged 18% compared to ≤9% in other years. Increases in forest litter in the attacked stand caused a more rapid decay in snow surface albedo in spring 2009 than in other years. Snow water equivalent near the onset of melt varied significantly from year to year; from 148 mm to 263 mm on April 1 in the clearcut, 88 mm to 191 mm in the attacked pine, and 65 mm to 144 mm in the green mature stand. The strongest

  18. Effects of snow condition on microbial respiration of Scots pine needle litter in a boreal forest

    NASA Astrophysics Data System (ADS)

    Ohnuki, Masataka; Domisch, Timo; Dannoura, Masako; Ataka, Mioko; Finér, Leena; Repo, Tapani; Osawa, Akira

    2016-04-01

    Climate warming scenarios predict decreasing snow depths and increasing winter precipitation in boreal forests ("rain on snow"). I These conditions may affect the decomposition and the microbial respiration of leaf litter, contributing a major part of tree litters, To understand how different snow conditions during winter would affect the microbial respiration of Scots pine needle litter in a boreal forest, we conducted a laboratory experiment using needle litter of two age classes (newly dropped and older litter). The experiment simulated four different winter treatments, followed by spring and early summer : (1) ambient snow cover (SNOW), (2) Compressed snow and ice encasement (ICE), (3) frozen flood (FLOOD) and (4) no snow cover at all (NO SNOW). The experiment was carried out in four walk-in dasotrons (n=3) with soil temperatures of -2° C and air temperatures of 2° C during winter and increased to 15° C and 20° C during spring, respectively . Needle litter samples were collected three times (prior to the winter, just after winter and at the end of the experiment). We evaluated the microbial respiration from the litter at several temperatures (-5° C, 0° C, 5° C and 12° C), the SIR index (an index estimating the microbial biomass), and the C/N ratio .And we calculated Q10 value (index of microbial respiration activity) using microbial respiration data. We found significant differences in microbial respiration between the newly dropped and older litter at the beginning and at the end of the experiment. However, there were no significant differences in Q10 value and the SIR (index of microbial biomass) between the different winter treatments. All samples showed decrease of microbial activity with time. Finally, we conclude that the winter snow conditions with mild air temperatures as used in our experiment, are not detrimentally affecting the Scots pine needle litter decomposition and its respiration.

  19. 7 CFR 1.620 - What supporting information must the Forest Service provide with its preliminary conditions?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 1 2011-01-01 2011-01-01 false What supporting information must the Forest Service provide with its preliminary conditions? 1.620 Section 1.620 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Conditions in FERC Hydropower Licenses Initiation of Hearing...

  20. 7 CFR 1.673 - How will the Forest Service analyze a proposed alternative and formulate its modified condition?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 1 2011-01-01 2011-01-01 false How will the Forest Service analyze a proposed alternative and formulate its modified condition? 1.673 Section 1.673 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Conditions in FERC Hydropower Licenses Alternatives Process § 1.673...

  1. 7 CFR 1.620 - What supporting information must the Forest Service provide with its preliminary conditions?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 1 2014-01-01 2014-01-01 false What supporting information must the Forest Service provide with its preliminary conditions? 1.620 Section 1.620 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Conditions in FERC Hydropower Licenses Initiation of Hearing...

  2. 7 CFR 1.620 - What supporting information must the Forest Service provide with its preliminary conditions?

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 1 2013-01-01 2013-01-01 false What supporting information must the Forest Service provide with its preliminary conditions? 1.620 Section 1.620 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Conditions in FERC Hydropower Licenses Initiation of Hearing...

  3. 7 CFR 1.673 - How will the Forest Service analyze a proposed alternative and formulate its modified condition?

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 1 2013-01-01 2013-01-01 false How will the Forest Service analyze a proposed alternative and formulate its modified condition? 1.673 Section 1.673 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Conditions in FERC Hydropower Licenses Alternatives Process § 1.673...

  4. 7 CFR 1.673 - How will the Forest Service analyze a proposed alternative and formulate its modified condition?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 1 2014-01-01 2014-01-01 false How will the Forest Service analyze a proposed alternative and formulate its modified condition? 1.673 Section 1.673 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Conditions in FERC Hydropower Licenses Alternatives Process § 1.673...

  5. 7 CFR 1.673 - How will the Forest Service analyze a proposed alternative and formulate its modified condition?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 1 2012-01-01 2012-01-01 false How will the Forest Service analyze a proposed alternative and formulate its modified condition? 1.673 Section 1.673 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Conditions in FERC Hydropower Licenses Alternatives Process § 1.673...

  6. 7 CFR 1.673 - How will the Forest Service analyze a proposed alternative and formulate its modified condition?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false How will the Forest Service analyze a proposed alternative and formulate its modified condition? 1.673 Section 1.673 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Conditions in FERC Hydropower Licenses Alternatives Process § 1.673...

  7. 7 CFR 1.620 - What supporting information must the Forest Service provide with its preliminary conditions?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 1 2012-01-01 2012-01-01 false What supporting information must the Forest Service provide with its preliminary conditions? 1.620 Section 1.620 Agriculture Office of the Secretary of Agriculture ADMINISTRATIVE REGULATIONS Conditions in FERC Hydropower Licenses Initiation of Hearing...

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

    PubMed

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

    2013-07-01

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

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

    PubMed

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

    2013-07-01

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

  10. Forest fire risk management and public participation in changing socioenvironmental conditions: a case study in a Mediterranean region.

    PubMed

    Tàbara, David; Saurí, David; Cerdan, Rufí

    2003-04-01

    Under current conditions of accelerated socioenvironmental change in the Mediterranean forested landscapes, fire is one of the most critical and difficult risks to tackle within the region. This article summarizes the lessons learned from a project based on the participatory integration of qualitative local stakeholders' knowledge with expert GIS fire simulations carried out in the County of El Bages, Catalonia, Spain. First, in this article, a theoretical model--the forest fire circle--is presented in order to explain the reasons for the rise in the damage and frequency of forest fires in this Mediterranean area. Second, it describes the methodology developed and the stages followed during the project. Results show that: (1) the advocacy of old forest reactive management paradigm assumptions and practices based on uncontrolled forest succession can put vast wooded areas of the Mediterranean basin at critical risk; and (2) forest fire management approaches that ignore the crucial role of long-term prevention and local capacity building strategies have failed. In the final section, the content and the specific dimensions of the old reactive paradigm that has characterized forest fire risk management in Catalonia are discussed and contrasted with the possibly emerging preventative paradigm. PMID:12731810

  11. Variable strength of forest stand attributes and weather conditions on the questing activity of Ixodes ricinus ticks over years in managed forests.

    PubMed

    Lauterbach, Ralf; Wells, Konstans; O'Hara, Robert B; Kalko, Elisabeth K V; Renner, Swen C

    2013-01-01

    Given the ever-increasing human impact through land use and climate change on the environment, we crucially need to achieve a better understanding of those factors that influence the questing activity of ixodid ticks, a major disease-transmitting vector in temperate forests. We investigated variation in the relative questing nymph densities of Ixodes ricinus in differently managed forest types for three years (2008-2010) in SW Germany by drag sampling. We used a hierarchical Bayesian modeling approach to examine the relative effects of habitat and weather and to consider possible nested structures of habitat and climate forces. The questing activity of nymphs was considerably larger in young forest successional stages of thicket compared with pole wood and timber stages. Questing nymph density increased markedly with milder winter temperatures. Generally, the relative strength of the various environmental forces on questing nymph density differed across years. In particular, winter temperature had a negative effect on tick activity across sites in 2008 in contrast to the overall effect of temperature across years. Our results suggest that forest management practices have important impacts on questing nymph density. Variable weather conditions, however, might override the effects of forest management practices on the fluctuations and dynamics of tick populations and activity over years, in particular, the preceding winter temperatures. Therefore, robust predictions and the detection of possible interactions and nested structures of habitat and climate forces can only be quantified through the collection of long-term data. Such data are particularly important with regard to future scenarios of forest management and climate warming. PMID:23372852

  12. Steam pretreatment of spruce forest residues: optimal conditions for biogas production and enzymatic hydrolysis.

    PubMed

    Janzon, Ron; Schütt, Fokko; Oldenburg, Saskia; Fischer, Elmar; Körner, Ina; Saake, Bodo

    2014-01-16

    Steam refining of non-debarked spruce forest residues was investigated as pretreatment for enzymatic hydrolysis as well as for biogas production. Pretreatment conditions were varied in the range of 190-220 °C, 5-10 min and 0-3.7% SO₂ according to a statistical design. For both applications highest product yields were predicted at 220 °C and 2.4% SO₂, whereas the reaction time had only a minor influence. The conformity of the model results allows the conclusion that enzymatic hydrolysis is a suitable test method to evaluate the degradability of lignocellulosic biomass in the biogas process. In control experiments under optimal conditions the results of the model were verified. The yield of total monomeric carbohydrates after enzymatic hydrolysis was equivalent to 55% of all theoretically available polysaccharides. The corresponding biogas yield from the pretreated wood amounted to 304 mL/gODM. Furthermore, furans produced under optimal process conditions showed no inhibitory effect on biogas production. It can be concluded that steam refining opens the structure of wood, thus improving the enzymatic hydrolysis of the polysaccharides to fermentable monomeric sugars and subsequently enabling a higher and faster production of biogas. Anaerobic fermentation of pretreated wood is a serious alternative to alcoholic fermentation especially when low quality wood grades and residues are used. Anaerobic digestion should be further investigated in order to diversify the biorefinery options for lignocellulosic materials.

  13. Recent Extreme Forest Fire Activity in Western Russia: Fire Danger Conditions, Fire Behavior and Smoke Transport

    NASA Astrophysics Data System (ADS)

    Stocks, B. J.; Fromm, M.; Goldammer, J.; Carr, R.; Sukhinin, A. I.

    2010-12-01

    During the summer of 2010, widespread forest and peatland fires in western Russia burned over hundreds of thousands of hectares, burning over croplands, destroying hundreds of homes, and directly causing the death of more than 50 people. Unprecedented drought conditions, combined with an extended heat wave, resulted in extreme fire danger conditions and explosive fire behavior in a region of Russia not noted for large fires. Several fires exhibited pyroconvection, injecting smoke directly into the upper troposphere and lower stratosphere, while deep-burning fires created major regional smoke problems. This smoke persisted in the heavily-populated areas around Moscow, exposing millions to high levels of ozone and particulate matter, and creating both immediate and longer-term health risks. This presentation will explore the drought conditions leading to the catastrophic fire behavior experienced in western Russia, and analyze fire behavior in terms of fuel consumption, smoke production, fire intensity levels, and pyroconvection. Impacts of regional and long-range smoke transport will also be discussed.

  14. Vertical gradient of climate change and climate tourism conditions in the Black Forest.

    PubMed

    Endler, Christina; Oehler, Karoline; Matzarakis, Andreas

    2010-01-01

    Due to the public discussion about global and regional warming, the regional climate and the modified climate conditions are analyzed exemplarily for three different regions in the southern Black Forest (southwest Germany). The driving question behind the present study was how can tourism adapt to modified climate conditions and associated changes to the tourism potential in low mountain ranges. The tourism potential is predominately based on the attractiveness of natural resources being climate-sensitive. In this study, regional climate simulations (A1B) are analyzed by using the REMO model. To analyze the climatic tourism potential, the following thermal, physical and aesthetic parameters are considered for the time span 1961-2050: thermal comfort, heat and cold stress, sunshine, humid-warm conditions (sultriness), fog, precipitation, storm, and ski potential (snow cover). Frequency classes of these parameters expressed as a percentage are processed on a monthly scale. The results are presented in form of the Climate-Tourism-Information-Scheme (CTIS). Due to warmer temperatures, winters might shorten while summers might lengthen. The lowland might be more affected by heat and sultriness (e.g., Freiburg due to the effects of urban climate). To adapt to a changing climate and tourism, the awareness of both stakeholders and tourists as well as the adaptive capability are essential.

  15. Chloride and organic chlorine in forest soils: storage, residence times, and influence of ecological conditions.

    PubMed

    Redon, Paul-Olivier; Abdelouas, Abdesselam; Bastviken, David; Cecchini, Sébastien; Nicolas, Manuel; Thiry, Yves

    2011-09-01

    Recent studies have shown that extensive chlorination of natural organic matter significantly affects chlorine (Cl) residence time in soils. This natural biogeochemical process must be considered when developing the conceptual models used as the basis for safety assessments regarding the potential health impacts of 36-chlorine released from present and planned radioactive waste disposal facilities. In this study, we surveyed 51 French forested areas to determine the variability in chlorine speciation and storage in soils. Concentrations of total chlorine (Cl(tot)) and organic chlorine (Cl(org)) were determined in litterfall, forest floor and mineral soil samples. Cl(org) constituted 11-100% of Cl(tot), with the highest concentrations being found in the humus layer (34-689 mg Cl(org) kg(-1)). In terms of areal storage (53 - 400 kg Cl(org) ha(-1)) the mineral soil dominated due to its greater thickness (40 cm). Cl(org) concentrations and estimated retention of organochlorine in the humus layer were correlated with Cl input, total Cl concentration, organic carbon content, soil pH and the dominant tree species. Cl(org) concentration in mineral soil was not significantly influenced by the studied environmental factors, however increasing Cl:C ratios with depth could indicate selective preservation of chlorinated organic molecules. Litterfall contributions of Cl were significant but generally minor compared to other fluxes and stocks. Assuming steady-state conditions, known annual wet deposition and measured inventories in soil, the theoretical average residence time calculated for total chlorine (inorganic (Cl(in)) and organic) was 5-fold higher than that estimated for Cl(in) alone. Consideration of the Cl(org) pool is therefore clearly important in studies of overall Cl cycling in terrestrial ecosystems. PMID:21761932

  16. Use of remotely sensed data for assessing forest stand conditions in the Eastern United States

    NASA Technical Reports Server (NTRS)

    Williams, D. L.; Nelson, R. F.

    1986-01-01

    Techniques for the detection, classification, and measurement of forest disturbances, using digital Landsat data for three study areas (Pennsynvania, North Carolina, and Maine) are reported. Results with respect to (1) the delineation and assessment of forest damage due to the use of two forest insect defoliators, and (2) qualitative assessment of the Multispectral Scanner (MSS) and the Thematic Mapper data for delineating forest stand characteristics are presented. Key results include a development of a statewide MSS digital data base and associated image-processing techniques for accurately delineating insect-damaged and healthy forest areas. For classification of broad land-cover classes which are spectrally homogeneous, the accuracy yielded by the use of either MSS data or TM Simulator data is similar. However, the TMS data provided 20 percent accuracy improvement over the MSS results when detailed (Level III) forest classes were mapped.

  17. The performance of sonic anemometers under foggy conditions - An intercomparision above a Taiwanese mountainous cloud forest

    NASA Astrophysics Data System (ADS)

    El-Madany, T.; Griessbaum, F.; Maneke, F.; Chu, H.-S.; Wu, C.-C.; Chang, S. C.; Hsia, Y.-J.; Juang, J.-Y.; Klemm, O.

    2010-07-01

    Foggy conditions are a toughness test for anemometers because the transceivers are continuously influenced by the deposition of fog-droplets. During a period of nearly four weeks three sonic anemometers where tested for their performance under foggy conditions. The anemometers were set up on a 24 meter high flux tower in a 14 meter high Chamaecyparis obtusa var. Formosana forest. The test anemometers were a Gill R3-50, a Young 81000V, and a Campbell CSAT3 (equipped with ‘dripping noses’). All anemometers were set up at one level on the highest platform of the tower. The performance was evaluated on the basis of 10 Hz data. The test site is located in the northwest of Taiwan at about 1650 m above sea level. This location is influenced by a steady diurnal wind system of valley winds during daytime and mountain winds during nighttime. The valley winds transport air masses from the coast up to the mountain where they cool down and fog development occurs. Due to this effect the site is highly frequented with fog. Results of this intercomparison will be presented.

  18. Response of the agile antechinus to habitat edge, configuration and condition in fragmented forest.

    PubMed

    Johnstone, Christopher P; Lill, Alan; Reina, Richard D

    2011-01-01

    Habitat fragmentation and degradation seriously threaten native animal communities. We studied the response of a small marsupial, the agile antechinus Antechinus agilis, to several environmental variables in anthropogenically fragmented Eucalyptus forest in south-east Australia. Agile antechinus were captured more in microhabitats dominated by woody debris than in other microhabitats. Relative abundances of both sexes were positively correlated with fragment core area. Male and female mass-size residuals were smaller in larger fragments. A health status indicator, haemoglobin-haematocrit residuals (HHR), did not vary as a function of any environmental variable in females, but male HHR indicated better health where sites' microhabitats were dominated by shrubs, woody debris and trees other than Eucalyptus. Females were trapped less often in edge than interior fragment habitat and their physiological stress level, indicated by the neutrophil/lymphocyte ratio in peripheral blood, was higher where fragments had a greater proportion of edge habitat. The latter trend was potentially due to lymphopoenia resulting from stress hormone-mediated leukocyte trafficking. Using multiple indicators of population condition and health status facilitates a comprehensive examination of the effects of anthropogenic disturbances, such as habitat fragmentation and degradation, on native vertebrates. Male agile antechinus' health responded negatively to habitat degradation, whilst females responded negatively to the proportion of edge habitat. The health and condition indicators used could be employed to identify conservation strategies that would make habitat fragments less stressful for this or similar native, small mammals.

  19. Conservative Diffusions: a Constructive Approach to Nelson's Stochastic Mechanics.

    NASA Astrophysics Data System (ADS)

    Carlen, Eric Anders

    In Nelson's stochastic mechanics, quantum phenomena are described in terms of diffusions instead of wave functions; this thesis is a study of that description. We emphasize that we are concerned here with the possibility of describing, as opposed to explaining, quantum phenomena in terms of diffusions. In this direction, the following questions arise: "Do the diffusions of stochastic mechanics--which are formally given by stochastic differential equations with extremely singular coefficients--really exist?" Given that they exist, one can ask, "Do these diffusions have physically reasonable sample path behavior, and can we use information about sample paths to study the behavior of physical systems?" These are the questions we treat in this thesis. In Chapter I we review stochastic mechanics and diffusion theory, using the Guerra-Morato variational principle to establish the connection with the Schroedinger equation. This chapter is largely expository; however, there are some novel features and proofs. In Chapter II we settle the first of the questions raised above. Using PDE methods, we construct the diffusions of stochastic mechanics. Our result is sufficiently general to be of independent mathematical interest. In Chapter III we treat potential scattering in stochastic mechanics and discuss direct probabilistic methods of studying quantum scattering problems. Our results provide a solid "Yes" in answer to the second question raised above.

  20. Breaking The Enzymatic Latch: Do Anaerobic Conditions Constrain Decomposition In Humid Tropical Forest Soil?

    NASA Astrophysics Data System (ADS)

    Hall, S. J.; Silver, W. L.

    2011-12-01

    Anaerobic conditions have been proposed to impose a "latch" on soil organic matter decomposition by inhibiting the activity of extracellular enzymes that catalyze the transformation of organic polymers into monomers for microbial assimilation. Here, we tested the hypothesis that anaerobiosis inhibits soil hydrolytic enzyme activity in a humid tropical forest ecosystem in Puerto Rico. We sampled surface and sub-surface soil from each of 59 plots (n = 118) stratified across distinct topographical zones (ridges, slopes, and valleys) known to vary in soil oxygen (O2) concentrations, and measured the potential activity of five hydrolytic enzymes that decompose carbon (C), nitrogen (N), and phosphorus (P) substrates. We measured reduced iron (Fe (II)) concentrations in soil extractions to provide a spatially and temporally integrated index of anaerobic microbial activity, since iron oxides constitute the dominant anaerobic terminal electron acceptor in this ecosystem. Surprisingly, we observed positive relationships between Fe (II) concentrations and the activity of all enzymes that we assayed. Linear mixed effects models that included Fe (II) concentration, topographic position, and their interaction explained between 30 to 70 % of the variance of enzyme activity of β-1,4-glucosidase, β-cellobiohydrolase, β-xylosidase, N-acetylglucosaminidase, and acid phosphatase. Soils from ridges and slopes contained between 10 and 800 μg Fe (II) g-1 soil, and exhibited consistently positive relationships (p < 0.0001) between Fe (II) and enzyme activity. Valley soils did not display significant relationships between enzyme activity and Fe (II), although they displayed variation in soil Fe (II) concentrations similar to ridges and slopes. Overall, valleys exhibited lower enzyme activity and lower Fe (II) concentrations than ridges or slopes, possibly related to decreased root biomass and soil C. Our data provide no indication that anaerobiosis suppresses soil enzyme activity, but

  1. Effects of foggy conditions on the measurement of stem respiration in a cloud forest in Taiwan

    NASA Astrophysics Data System (ADS)

    Chang, S.-C.; Wang, H.-K.; Lin, Y.-C.; Hsia, Y.-J.

    2010-07-01

    Stem CO2 efflux of a Chamaecyparis obtusa var. formosana forest ecosystem was measured at the Chi-Lan Mountain (CLM) site in northern Taiwan. The site is located at an altitude of 1650 m and is subjected to frequent fog coverage around the year. Stem CO2 efflux was measured continuously at 1 m height by horizontally mounting an automatic soil respiration chamber system (LI-8100 Survey Chamber, LI-COR) on the stem surface. Every 10 min, the chamber was closed for 2 min for the measurement of CO2 concentration within the closed system. Stem temperature beside the chamber was monitored by a thermistor inserted 3 cm into the stem. Sapflow velocity was recorded using thermal dissipation probes installed on five nearby Chamaecyparis obtusa var. formosana trees. The data from May 2009 was used in the current analysis. Under clear weather, e. g. on May 8, 2009, the diurnal stem CO2 efflux rate vs. stem temperature showed a clear hysteresis loop. The daytime stem CO2 efflux rates were lower than the potential values, which were predicted by the nighttime stem temperature-stem CO2 efflux relation. The magnitude of the daytime depression of the stem CO2 efflux was positively correlated with the sapflow velocity. On the contrary, when the site was submerged in fog during the daytime, the hysteresis did not take place and the very low sapflow velocities caused only minor decrease in the daytime stem CO2 efflux compared to those in nighttime. In May 2009, the daily accumulated daytime depression of stem CO2 efflux ranged from 0.54 to 7.70 mmol m-2. The daily daytime foggy time had a negative linear correlation with the amount of daily depression. The effects of foggy conditions on the stem CO2 efflux measurement might have some ecological implications. The frequent occurrence of fog in the cloud forests, where the transpiration rates are low, might guarantee a less biased estimation of stem respiration by the chamber method. The measured stem CO2 efflux might significantly

  2. Water Quality Conditions Associated with Cattle Grazing and Recreation on National Forest Lands

    PubMed Central

    Roche, Leslie M.; Kromschroeder, Lea; Atwill, Edward R.; Dahlgren, Randy A.; Tate, Kenneth W.

    2013-01-01

    There is substantial concern that microbial and nutrient pollution by cattle on public lands degrades water quality, threatening human and ecological health. Given the importance of clean water on multiple-use landscapes, additional research is required to document and examine potential water quality issues across common resource use activities. During the 2011 grazing-recreation season, we conducted a cross sectional survey of water quality conditions associated with cattle grazing and/or recreation on 12 public lands grazing allotments in California. Our specific study objectives were to 1) quantify fecal indicator bacteria (FIB; fecal coliform and E. coli), total nitrogen, nitrate, ammonium, total phosphorus, and soluble-reactive phosphorus concentrations in surface waters; 2) compare results to a) water quality regulatory benchmarks, b) recommended maximum nutrient concentrations, and c) estimates of nutrient background concentrations; and 3) examine relationships between water quality, environmental conditions, cattle grazing, and recreation. Nutrient concentrations observed throughout the grazing-recreation season were at least one order of magnitude below levels of ecological concern, and were similar to U.S. Environmental Protection Agency (USEPA) estimates for background water quality conditions in the region. The relative percentage of FIB regulatory benchmark exceedances widely varied under individual regional and national water quality standards. Relative to USEPA’s national E. coli FIB benchmarks–the most contemporary and relevant standards for this study–over 90% of the 743 samples collected were below recommended criteria values. FIB concentrations were significantly greater when stream flow was low or stagnant, water was turbid, and when cattle were actively observed at sampling. Recreation sites had the lowest mean FIB, total nitrogen, and soluble-reactive phosphorus concentrations, and there were no significant differences in FIB and

  3. Denudation rates derived from spatially-averaged cosmogenic nuclide analysis in Nelson catchments, South Island, New Zealand

    NASA Astrophysics Data System (ADS)

    Burdis, A.; Norton, K. P.; Ditchburn, B.; Zondervan, A.

    2013-12-01

    events. This is highlighted by sediment yields reaching ~2535 t km-2 yr-1 following storm events in the Nelson region (Basher et al., 2011). At least on the northern South Island of New Zealand, extreme climatic events appear to be the main driver of elevated denudation rates. Basher, L., Hicks, D., Clapp, B., & Hewitt, T. (2011). Sediment Yield Response to Large Storm Events and Forest Harvesting, Motueka River, New Zealand. New Zealand Journal ofMarine and Freshwater Research, Vol. 45, No. 3 , 333-356.

  4. Groupwise conditional random forests for automatic shape classification and contour quality assessment in radiotherapy planning.

    PubMed

    McIntosh, Chris; Svistoun, Igor; Purdie, Thomas G

    2013-06-01

    Radiation therapy is used to treat cancer patients around the world. High quality treatment plans maximally radiate the targets while minimally radiating healthy organs at risk. In order to judge plan quality and safety, segmentations of the targets and organs at risk are created, and the amount of radiation that will be delivered to each structure is estimated prior to treatment. If the targets or organs at risk are mislabelled, or the segmentations are of poor quality, the safety of the radiation doses will be erroneously reviewed and an unsafe plan could proceed. We propose a technique to automatically label groups of segmentations of different structures from a radiation therapy plan for the joint purposes of providing quality assurance and data mining. Given one or more segmentations and an associated image we seek to assign medically meaningful labels to each segmentation and report the confidence of that label. Our method uses random forests to learn joint distributions over the training features, and then exploits a set of learned potential group configurations to build a conditional random field (CRF) that ensures the assignment of labels is consistent across the group of segmentations. The CRF is then solved via a constrained assignment problem. We validate our method on 1574 plans, consisting of 17[Formula: see text] 579 segmentations, demonstrating an overall classification accuracy of 91.58%. Our results also demonstrate the stability of RF with respect to tree depth and the number of splitting variables in large data sets.

  5. Using conditional inference trees and random forests to predict the bioaccumulation potential of organic chemicals.

    PubMed

    Strempel, Sebastian; Nendza, Monika; Scheringer, Martin; Hungerbühler, Konrad

    2013-04-01

    The present study presents a data-oriented, tiered approach to assessing the bioaccumulation potential of chemicals according to the European chemicals regulation on Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH). The authors compiled data for eight physicochemical descriptors (partition coefficients, degradation half-lives, polarity, and so forth) for a set of 713 organic chemicals for which experimental values of the bioconcentration factor (BCF) are available. The authors employed supervised machine learning methods (conditional inference trees and random forests) to derive relationships between the physicochemical descriptors and the BCF values. In a first tier, the authors established rules for classifying a chemical as bioaccumulative (B) or nonbioaccumulative (non-B). In a second tier, the authors developed a new tool for estimating numerical BCF values. For both cases the optimal set of relevant descriptors was determined; these are biotransformation half-life and octanol-water distribution coefficient (log D) for the classification rules and log D, biotransformation half-life, and topological polar surface area for the BCF estimation tool. The uncertainty of the BCF estimates obtained with the new estimation tool was quantified by comparing the estimated and experimental BCF values of the 713 chemicals. Comparison with existing BCF estimation methods indicates that the performance of this new BCF estimation tool is at least as high as that of existing methods. The authors recommend the present study's classification rules and BCF estimation tool for a consensus application in combination with existing BCF estimation methods.

  6. Tree growth and forest ecosystem functioning in Eurasia under extreme climate conditions

    NASA Astrophysics Data System (ADS)

    Saurer, Matthias; Kirdyanov, Alexander; Prokushkin, Anatoly; Bryukhanova, Marina; Knorre, Anastasia; Nasyrov, Muhtor; Frank, David; Treydte, Kerstin; Sidorova, Olga; Siegwolf, Rolf

    2013-04-01

    The main goal of this study is to improve our understanding of the influence of a changing climate on trees in extreme conditions by a detailed analysis of the factors controlling tree-ring growth. We investigated forest ecosystems in regions that are very sensitive to climatic changes and where rapid and dramatic environmental and climatic changes are on-going, namely, the high latitude permafrost region in Central Siberia (Russia), the semi-arid dry areas in Central Asia (Uzbekistan) and high-altitude sites in the Alps (Switzerland). Tree-ring parameters studied were ring-width, density, cell number and structure and the ratio of carbon and oxygen isotopes. An important aspect of the work was the characterization of seasonal growth and water supply of trees. Intra-seasonal dynamics of tree-ring formation was correlated with monitored environmental factors, such as air and soil temperature and moisture, permafrost depth and the isotope composition of soil water, of precipitation, and of stream water. Intra-annual and long-term variability of the main tree-ring parameters were compared for the different regions. The results obtained help us to understand better tree-physiological processes valid under contrasting environmental conditions. For instance, the relationship between the onset of cell division in the cambium and the thermo-hydrological soil regime was used to determine the period of the year with the highest influence on the start of tree-ring formation. Seasonally resolved oxygen isotope depth profiles of soil water and concurrent xylem and leaf water measurements show the importance of time-lags between precipitation, leaf processes and growth. The data obtained are important for improving tree-ring growth models and estimating future tree growth under climate change. Funding: SNF SCOPES IZ73Z0_128035

  7. Influence of forest stands on soil and ecosystem carbon stocks in the conditions of the European part of Russia

    NASA Astrophysics Data System (ADS)

    Kaganov, Vladimir

    2016-04-01

    Forest stands are one of the most important components of ecosystems, both in Russia and around the world and at the same time forest vegetation is able to provide environment-modifying effect on the occupied landscape and, in particular, on the soil cover. Currently, due to the large interest in the carbon cycle, there is a question about the influence of forest vegetation on carbon stocks in ecosystems and in particular in the soil cover. To perform the study we selected 9 objects located in the European part of Russia from the area of the southern taiga to the semi-desert zone: Novgorod region, Kostroma region, Moscow region (2 objects), Penza region, Voronezh region, Volgograd region (2 objects) and Astrakhan region. For studying the influence of forest vegetation on the soil`s carbon, we organized the following experiment scheme: in each of the objects two key sites were selected, so that they originally were in the same soil conditions and the difference between them was only in a course development of vegetation - forest or grass. One part of the experimental sites, presenting forest vegetation, were the restored forests on abandoned lands with the age of 70-200 years. The second part of the experimental sites were artificial forest plantations aged from 60 to 112 years planted on the originally treeless forest-steppe or steppe landscapes. Perennial hayfields, perennial abandoned agricultural landscapes and virgin steppe areas were used as reference sites with grass vegetation. For each forest site we estimated the major carbon pools: phytomass, mortmass (dead wood, dry grass), debris, litter and soil. All data were recalculated using the conversion factors in carbon stocks in t C ha-1. We collected soil samples every 10 cm until the depth of 50 cm, and then at 50-75 and 75-100 cm soil layers. Bulk density and total organic carbon were determined by CHN analyzer. As a result, the soil`s carbon was also calculated into t C ha-1. We found out that the total

  8. Forest soil respiration rate and delta13C is regulated by recent above ground weather conditions.

    PubMed

    Ekblad, Alf; Boström, Björn; Holm, Anders; Comstedt, Daniel

    2005-03-01

    Soil respiration, a key component of the global carbon cycle, is a major source of uncertainty when estimating terrestrial carbon budgets at ecosystem and higher levels. Rates of soil and root respiration are assumed to be dependent on soil temperature and soil moisture yet these factors often barely explain half the seasonal variation in soil respiration. We here found that soil moisture (range 16.5-27.6% of dry weight) and soil temperature (range 8-17.5 degrees C) together explained 55% of the variance (cross-validated explained variance; Q2) in soil respiration rate (range 1.0-3.4 micromol C m(-2) s(-1)) in a Norway spruce (Picea abies) forest. We hypothesised that this was due to that the two components of soil respiration, root respiration and decomposition, are governed by different factors. We therefore applied PLS (partial least squares regression) multivariate modelling in which we, together with below ground temperature and soil moisture, used the recent above ground air temperature and air humidity (vapour pressure deficit, VPD) conditions as x-variables. We found that air temperature and VPD data collected 1-4 days before respiration measurements explained 86% of the seasonal variation in the rate of soil respiration. The addition of soil moisture and soil temperature to the PLS-models increased the Q2 to 93%. delta13C analysis of soil respiration supported the hypotheses that there was a fast flux of photosynthates to root respiration and a dependence on recent above ground weather conditions. Taken together, our results suggest that shoot activities the preceding 1-6 days influence, to a large degree, the rate of root and soil respiration. We propose this above ground influence on soil respiration to be proportionally largest in the middle of the growing season and in situations when there is large day-to-day shifts in the above ground weather conditions. During such conditions soil temperature may not exert the major control on root respiration. PMID

  9. The Influence Of Variability Of Water Resources In Lowland Forests On Selected Parameters Describing The Condition Of Trees

    NASA Astrophysics Data System (ADS)

    Tyszka, Jan; Stolarek, Andrzej; Fronczak, Ewa

    2014-01-01

    The influence of water conditions on the condition and growth of tree stands has been analysed in the context of the climatic and hydrological functions forest plays. Long observational series obtained for precipitation, outflow and depths below the surface of the water table have been put together with measured increases in the breast-height diameters of Scots pines and the severity of crown defoliation observable in selected tree species growing on the Polish Lowland, in order to determine the overall scope to the reaction stand condition manifests in the face of ongoing variability of water conditions within forest. An overall improvement in the condition of stands over the last 20 years does not disguise several-year cyclicity to changes capable of shaping the situation, i.a. departures from long-term mean values for precipitation totals and groundwater levels. The condition of stands is seen to worsen in both dry and wet years. Analysis of the degree to which pine, spruce and broadleaved stands experience defoliation points to spruce stands responding most to extreme hydro-climatic conditions. Extreme situations as regards water resources were seen to involve a response over two-year time intervals in the case of coniferous stands. Unsurprisingly, optimal growing-season (June-September) precipitation totals correspond with long-term average figures, while being slightly higher for spruce (at 384 mm), than for Scots pine or broadleaved species (375 mm). The relationships reported gain confirmation in analysis of periodic change in breast-height diameter increments characterising Scots pines, whose growth is seen to depend closely, not only on precipitation, but also above all on the depth of the water table in the summer half-year. Optimal depths of the water table proved to be different, being around 20 cm below ground in the case of marshy coniferous forest, 80 cm in wet habitats, and 135 cm in fresh habitats. Depending on the possibilities for water to soak

  10. Monitoring of environmental conditions in taiga forests using ERS-1 SAR

    SciTech Connect

    Rignot, E.; Way, J.B.; McDonald, K. ); Viereck, L.; Williams, C.; Adams, P.; Payne, C.; Wood, W. ); Shi, J. )

    1994-08-01

    Synthetic-aperture radar images of forest site near Manley Hot Springs (64[degree]N, 151[degree]W), Alaska, were collected between August 1991 and December 1991, day and night, every 3 days, at C-band frequency ([lambda] = 5.7 cm), vertical receive and transmit polarization, by the European Space Agency First Remote Sensing Satellite, ERS-1. During the same period, air and soil temperatures and dielectric and gravimetric moisture properties of the forest canopy and forest floor were monitored in three forest stands dominated, respectively, by black spruce (Picea mariana), white spruce (Picea glauca), and balsam poplar (Populus balsamifera). The calibrated ERS-1 radar backscatter values, [sigma][degree], of the forest stands are shown to exhibit a pronounced temporal pattern, with little separability between tree species. The largest change in [sigma][degree], a 3-dB decrease almost independent of tree species, is observed in early winter when the soil and vegetation freeze. In the summer, temporal fluctuations in [sigma][degree] are about 1--2 dB in magnitude, depending on tree species. Diurnal variations in [sigma][degree] are as large as 2 dB during fall freeze-up, and less than 1 dB in summer and winter. These temporal variations in radar backscatter from the forest are interpreted using the MIMICS radar backscatter model and the in situ surface observations as due to changes in the dielectric properties of the forest floor and forest canopy induced by precipitation (summer), drought (fall), and freezing (fall-winter) events. In winter, [sigma][degree] increases across the entire landscape, probably because of volume scattering from large depth hoar ice crystals forming in the snow pack.

  11. Simulating the carbon balance of a temperate larch forest under various meteorological conditions

    PubMed Central

    Toda, Motomu; Yokozawa, Masayuki; Sumida, Akihiro; Watanabe, Tsutomu; Hara, Toshihiko

    2007-01-01

    Background Changes in the timing of phenological events may cause the annual carbon budget of deciduous forests to change. Therefore, one should take such events into account when evaluating the effects of global warming on deciduous forests. In this article, we report on the results of numerical experiments done with a model that includes a phenological module simulating the timing of bud burst and other phenological events and estimating maximum leaf area index. Results This study suggests that the negative effects of warming on tree productivity (net primary production) outweigh the positive effects of a prolonged growing season. An increase in air temperature by 3°C (5°C) reduces cumulative net primary production by 21.3% (34.2%). Similarly, cumulative net ecosystem production (the difference between cumulative net primary production and heterotrophic respiration) decreases by 43.5% (64.5%) when temperatures are increased by 3°C (5°C). However, the positive effects of CO2 enrichment (2 × CO2) outweigh the negative effects of warming (<5°C). Conclusion Although the model was calibrated and validated for a specific forest ecosystem, the implications of the study may be extrapolated to deciduous forests in cool-temperate zones. These forests share common features, and it can be conjectured that carbon stocks would increase in such forests in the face of doubled CO2 and increased temperatures as long as the increase in temperature does not exceed 5°C. PMID:17535447

  12. Radiocarbon ages of terrestrial gastropods extend duration of ice-free conditions at the Two Creeks forest bed, Wisconsin, USA

    USGS Publications Warehouse

    Rech, Jason A.; Nekola, Jeffrey C.; Pigati, Jeffrey S.

    2012-01-01

    Analysis of terrestrial gastropods that underlie the late Pleistocene Two Creeks forest bed (~ 13,800–13,500 cal yr BP) in eastern Wisconsin, USA provides evidence for a mixed tundra-taiga environment prior to formation of the taiga forest bed. Ten new AMS 14C analyses on terrestrial gastropod shells indicate the mixed tundra-taiga environment persisted from ~ 14,500 to 13,900 cal yr BP. The Twocreekan climatic substage, representing ice-free conditions on the shore of Lake Michigan, therefore began near the onset of peak warming conditions during the Bølling–Allerød interstadial and lasted ~ 1000 yr, nearly 600 yr longer than previously thought. These results provide important data for understanding the response of continental ice sheets to global climate forcing and demonstrate the potential of using terrestrial gastropod fossils for both environmental reconstruction and age control in late Quaternary sediments.

  13. Impacts of forest harvest on cold season land surface conditions and land-atmosphere interactions in northern Great Lakes states

    NASA Astrophysics Data System (ADS)

    Garcia, Matthew; Özdogan, Mutlu; Townsend, Philip A.

    2014-09-01

    Land cover change, including temporary disturbances such as forest harvests, can significantly affect established regimes of surface energy balance and moisture exchange, altering flux processes that drive weather and climate. We examined the impacts of forest harvest on winter land-atmosphere interactions in a temperate region using high-resolution numerical modeling methods in paired simulations. Using the WRF-ARW atmospheric model and the Noah land surface model, we simulated the balance of surface sensible and latent heat fluxes and the development and dissipation of a stable nocturnal boundary layer during generally calm synoptic conditions. Our results show reduced daily-average snow-covered land surface sensible heat flux (by 80%) and latent heat flux (by 60%) to the atmosphere in forest clearings due to albedo effects and rebalancing of the surface energy budget. We found a land surface cooling effect (-8 W m-2) in snow-covered cleared areas, consistent with prior modeling studies and conceptual understanding of the mechanisms for midlatitude deforestation to offset anthropogenic global warming at local scales. Results also demonstrate impacts of forest clearing on the passage of a weak cold front due to altered near-surface winds and boundary layer stability. We show significant differences in both surface conditions and fluxes between harvested and undisturbed forest areas. Our results demonstrate the potential utility of high-resolution remote sensing analyses to represent transient land cover changes in model simulations of weather and climate, which are usually undertaken at coarser resolutions and often overlook these changes at the land surface.

  14. Classification of riparian forest species and health condition using multi-temporal and hyperspatial imagery from unmanned aerial system.

    PubMed

    Michez, Adrien; Piégay, Hervé; Lisein, Jonathan; Claessens, Hugues; Lejeune, Philippe

    2016-03-01

    Riparian forests are critically endangered many anthropogenic pressures and natural hazards. The importance of riparian zones has been acknowledged by European Directives, involving multi-scale monitoring. The use of this very-high-resolution and hyperspatial imagery in a multi-temporal approach is an emerging topic. The trend is reinforced by the recent and rapid growth of the use of the unmanned aerial system (UAS), which has prompted the development of innovative methodology. Our study proposes a methodological framework to explore how a set of multi-temporal images acquired during a vegetative period can differentiate some of the deciduous riparian forest species and their health conditions. More specifically, the developed approach intends to identify, through a process of variable selection, which variables derived from UAS imagery and which scale of image analysis are the most relevant to our objectives.The methodological framework is applied to two study sites to describe the riparian forest through two fundamental characteristics: the species composition and the health condition. These characteristics were selected not only because of their use as proxies for the riparian zone ecological integrity but also because of their use for river management.The comparison of various scales of image analysis identified the smallest object-based image analysis (OBIA) objects (ca. 1 m(2)) as the most relevant scale. Variables derived from spectral information (bands ratios) were identified as the most appropriate, followed by variables related to the vertical structure of the forest. Classification results show good overall accuracies for the species composition of the riparian forest (five classes, 79.5 and 84.1% for site 1 and site 2). The classification scenario regarding the health condition of the black alders of the site 1 performed the best (90.6%).The quality of the classification models developed with a UAS-based, cost-effective, and semi-automatic approach

  15. Classification of riparian forest species and health condition using multi-temporal and hyperspatial imagery from unmanned aerial system.

    PubMed

    Michez, Adrien; Piégay, Hervé; Lisein, Jonathan; Claessens, Hugues; Lejeune, Philippe

    2016-03-01

    Riparian forests are critically endangered many anthropogenic pressures and natural hazards. The importance of riparian zones has been acknowledged by European Directives, involving multi-scale monitoring. The use of this very-high-resolution and hyperspatial imagery in a multi-temporal approach is an emerging topic. The trend is reinforced by the recent and rapid growth of the use of the unmanned aerial system (UAS), which has prompted the development of innovative methodology. Our study proposes a methodological framework to explore how a set of multi-temporal images acquired during a vegetative period can differentiate some of the deciduous riparian forest species and their health conditions. More specifically, the developed approach intends to identify, through a process of variable selection, which variables derived from UAS imagery and which scale of image analysis are the most relevant to our objectives.The methodological framework is applied to two study sites to describe the riparian forest through two fundamental characteristics: the species composition and the health condition. These characteristics were selected not only because of their use as proxies for the riparian zone ecological integrity but also because of their use for river management.The comparison of various scales of image analysis identified the smallest object-based image analysis (OBIA) objects (ca. 1 m(2)) as the most relevant scale. Variables derived from spectral information (bands ratios) were identified as the most appropriate, followed by variables related to the vertical structure of the forest. Classification results show good overall accuracies for the species composition of the riparian forest (five classes, 79.5 and 84.1% for site 1 and site 2). The classification scenario regarding the health condition of the black alders of the site 1 performed the best (90.6%).The quality of the classification models developed with a UAS-based, cost-effective, and semi-automatic approach

  16. Local climatic conditions constrain soil yeast diversity patterns in Mediterranean forests, woodlands and scrub biome.

    PubMed

    Yurkov, Andrey M; Röhl, Oliver; Pontes, Ana; Carvalho, Cláudia; Maldonado, Cristina; Sampaio, José Paulo

    2016-02-01

    Soil yeasts represent a poorly known fraction of the soil microbiome due to limited ecological surveys. Here, we provide the first comprehensive inventory of cultivable soil yeasts in a Mediterranean ecosystem, which is the leading biodiversity hotspot for vascular plants and vertebrates in Europe. We isolated and identified soil yeasts from forested sites of Serra da Arrábida Natural Park (Portugal), representing the Mediterranean forests, woodlands and scrub biome. Both cultivation experiments and the subsequent species richness estimations suggest the highest species richness values reported to date, resulting in a total of 57 and 80 yeast taxa, respectively. These values far exceed those reported for other forest soils in Europe. Furthermore, we assessed the response of yeast diversity to microclimatic environmental factors in biotopes composed of the same plant species but showing a gradual change from humid broadleaf forests to dry maquis. We observed that forest properties constrained by precipitation level had strong impact on yeast diversity and on community structure and lower precipitation resulted in an increased number of rare species and decreased evenness values. In conclusion, the structure of soil yeast communities mirrors the environmental factors that affect aboveground phytocenoses, aboveground biomass and plant projective cover.

  17. Color estimation of forest-steppe soils by digital photography under laboratory conditions

    NASA Astrophysics Data System (ADS)

    Valeeva, A. A.; Aleksandrova, A. B.; Koposov, G. F.

    2016-09-01

    Numerical values in the RGB, HSB, and L*a*b systems for the colors of structurally differentiated soils (Luvisols) in the Volga-Kama forest-steppe have been obtained using a digital camera. A high correlation has been revealed between the soil color and the content of humus in the range 0.39-6%. When the content of humus exceeds 6%, the color of humus horizon varies only slightly. A regression equation within the RRGB range from 85 to 173 has been calculated for the rapid determination of humus content in low- and medium-humus texturally differentiated soils of the Volga-Kama forest-steppe.

  18. Imported Case of Acute Respiratory Tract Infection Associated with a Member of Species Nelson Bay Orthoreovirus

    PubMed Central

    Sakai, Kouji; Singh, Harpal; Himeji, Daisuke; Kikuchi, Ikuo; Ueda, Akira; Yamamoto, Seigo; Miura, Miho; Shioyama, Yoko; Kawano, Kimiko; Nagaishi, Tokiko; Saito, Minako; Minomo, Masumi; Iwamoto, Naoyasu; Hidaka, Yoshio; Sohma, Hirotoshi; Kobayashi, Takeshi; Kanai, Yuta; Kawagishi, Takehiro; Nagata, Noriyo; Fukushi, Shuetsu; Mizutani, Tetsuya; Tani, Hideki; Taniguchi, Satoshi; Fukuma, Aiko; Shimojima, Masayuki; Kurane, Ichiro; Kageyama, Tsutomu; Odagiri, Takato; Saijo, Masayuki; Morikawa, Shigeru

    2014-01-01

    A Japanese man suffered from acute respiratory tract infection after returning to Japan from Bali, Indonesia in 2007. Miyazaki-Bali/2007, a strain of the species of Nelson Bay orthoreovirus, was isolated from the patient's throat swab using Vero cells, in which syncytium formation was observed. This is the sixth report describing a patient with respiratory tract infection caused by an orthoreovirus classified to the species of Nelson Bay orthoreovirus. Given the possibility that all of the patients were infected in Malaysia and Indonesia, prospective surveillance on orthoreovirus infections should be carried out in Southeast Asia. Furthermore, contact surveillance study suggests that the risk of human-to-human infection of the species of Nelson Bay orthoreovirus would seem to be low. PMID:24667794

  19. Differential winter stemflow generation under contrasting storm conditions in a southern New England broad-leaved deciduous forest

    NASA Astrophysics Data System (ADS)

    Levia, Delphis F., Jr.

    2004-04-01

    Despite the importance of stemflow as a hydroecological process, differential winter stemflow generation among and within precipitation types (e.g. snow, rain-to-snow) is poorly understood. The purpose of the present study is to understand winter stemflow generation better under contrasting meteorological conditions in a leafless deciduous forest. It is hypothesized that stemflow volume and production, expressed as a funnelling ratio, will differ significantly among and within precipitation event types. Acceptance of this hypothesis would mean that intra-event meteorological conditions have a significant and discernible effect on stemflow production in deciduous forests, differentially affecting soil moisture, groundwater recharge, soil solution chemistry, and nutrient cycling. Stemflow volumes generated from seven canopy trees were monitored in a leafless deciduous forest of southern New England on a precipitation event basis over two successive winter seasons. Stemflow volume was found to differ significantly among different and same-type precipitation events. A rain event that occurred on 8 December 1998 and snow-to-rain event on 18 January 1999 were of similar duration, magnitude, and intensity, yet produced stemflow volumes that differed by a factor of 4. For two snow-to-rain events, stemflow volumes differed by a factor of 11. Stemflow production even varies widely within a discrete precipitation event as a function of meteorological conditions. Significant differential stemflow yield under contrasting storm conditions obviates generalizations concerning stemflow production as a function of precipitation event type and necessitates a deeper, process-level understanding of winter stemflow generation before modelling exercises are undertaken.

  20. Evaluating the condition of a mangrove forest of the Mexican Pacific based on an estimated leaf area index mapping approach.

    PubMed

    Kovacs, J M; King, J M L; Flores de Santiago, F; Flores-Verdugo, F

    2009-10-01

    Given the alarming global rates of mangrove forest loss it is important that resource managers have access to updated information regarding both the extent and condition of their mangrove forests. Mexican mangroves in particular have been identified as experiencing an exceptional high annual rate of loss. However, conflicting studies, using remote sensing techniques, of the current state of many of these forests may be hindering all efforts to conserve and manage what remains. Focusing on one such system, the Teacapán-Agua Brava-Las Haciendas estuarine-mangrove complex of the Mexican Pacific, an attempt was made to develop a rapid method of mapping the current condition of the mangroves based on estimated LAI. Specifically, using an AccuPAR LP-80 Ceptometer, 300 indirect in situ LAI measurements were taken at various sites within the black mangrove (Avicennia germinans) dominated forests of the northern section of this system. From this sample, 225 measurements were then used to develop linear regression models based on their relationship with corresponding values derived from QuickBird very high resolution optical satellite data. Specifically, regression analyses of the in situ LAI with both the normalized difference vegetation index (NDVI) and the simple ration (SR) vegetation index revealed significant positive relationships [LAI versus NDVI (R (2) = 0.63); LAI versus SR (R (2) = 0.68)]. Moreover, using the remaining sample, further examination of standard errors and of an F test of the residual variances indicated little difference between the two models. Based on the NDVI model, a map of estimated mangrove LAI was then created. Excluding the dead mangrove areas (i.e. LAI = 0), which represented 40% of the total 30.4 km(2) of mangrove area identified in the scene, a mean estimated LAI value of 2.71 was recorded. By grouping the healthy fringe mangrove with the healthy riverine mangrove and by grouping the dwarf mangrove together with the poor condition

  1. Evaluating the condition of a mangrove forest of the Mexican Pacific based on an estimated leaf area index mapping approach.

    PubMed

    Kovacs, J M; King, J M L; Flores de Santiago, F; Flores-Verdugo, F

    2009-10-01

    Given the alarming global rates of mangrove forest loss it is important that resource managers have access to updated information regarding both the extent and condition of their mangrove forests. Mexican mangroves in particular have been identified as experiencing an exceptional high annual rate of loss. However, conflicting studies, using remote sensing techniques, of the current state of many of these forests may be hindering all efforts to conserve and manage what remains. Focusing on one such system, the Teacapán-Agua Brava-Las Haciendas estuarine-mangrove complex of the Mexican Pacific, an attempt was made to develop a rapid method of mapping the current condition of the mangroves based on estimated LAI. Specifically, using an AccuPAR LP-80 Ceptometer, 300 indirect in situ LAI measurements were taken at various sites within the black mangrove (Avicennia germinans) dominated forests of the northern section of this system. From this sample, 225 measurements were then used to develop linear regression models based on their relationship with corresponding values derived from QuickBird very high resolution optical satellite data. Specifically, regression analyses of the in situ LAI with both the normalized difference vegetation index (NDVI) and the simple ration (SR) vegetation index revealed significant positive relationships [LAI versus NDVI (R (2) = 0.63); LAI versus SR (R (2) = 0.68)]. Moreover, using the remaining sample, further examination of standard errors and of an F test of the residual variances indicated little difference between the two models. Based on the NDVI model, a map of estimated mangrove LAI was then created. Excluding the dead mangrove areas (i.e. LAI = 0), which represented 40% of the total 30.4 km(2) of mangrove area identified in the scene, a mean estimated LAI value of 2.71 was recorded. By grouping the healthy fringe mangrove with the healthy riverine mangrove and by grouping the dwarf mangrove together with the poor condition

  2. Radical Questioning on the Long Walk to Freedom: Nelson Mandela and the Practice of Critical Reflection

    ERIC Educational Resources Information Center

    Brookfield, Stephen

    2008-01-01

    Nelson Mandela's autobiography "The Long Walk to Freedom" describes how an iconic political activist and freedom fighter reflected on, and sometimes modified, four core assumptions at the heart of his struggle to overturn the White supremacist, minority hegemony and create a free South Africa. Critical reflection's focus is on understanding the…

  3. 78 FR 56224 - Hydro Nelson, Ltd.; Hydro-WM, LLC; Notice of Transfer of Exemption

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-12

    ... Energy Regulatory Commission Hydro Nelson, Ltd.; Hydro-WM, LLC; Notice of Transfer of Exemption 1. By documentation filed July 8, 2013 and supplemented on September 4, 2013, Hydro-WM, LLC informed the Commission... March 26, 1982,\\1\\ has been transferred to Hydro-WM, LLC. The project is located on the Rockfish...

  4. Passageless Comprehension on the "Nelson-Denny Reading Test": Well above Chance for University Students

    ERIC Educational Resources Information Center

    Coleman, Chris; Lindstrom, Jennifer; Nelson, Jason; Lindstrom, William; Gregg, K. Noel

    2010-01-01

    The comprehension section of the "Nelson-Denny Reading Test" (NDRT) is widely used to assess the reading comprehension skills of adolescents and adults in the United States. In this study, the authors explored the content validity of the NDRT Comprehension Test (Forms G and H) by asking university students (with and without at-risk status for…

  5. Shaping Influences on the Leadership of Genghis Khan, George Washington, and Nelson Mandela: Applications for Educators

    ERIC Educational Resources Information Center

    Bongila, Jean-Pierre

    2011-01-01

    Using a prosopographical methodology this study examines common leadership influences that might have existed among Genghis Khan, George Washington, and Nelson Mandela. Shoup (2005) suggests that the following seven influences have contributed to nurturing the leadership of 12 renowned individuals: involved parents, happy childhood, formal,…

  6. Adult Learners: New Norms on the Nelson-Denny Reading Test for Healthcare Professionals.

    ERIC Educational Resources Information Center

    Haught, Patricia A.; Walls, Richard T.

    2002-01-01

    Presents new norms on the Nelson-Denny Reading Test for healthcare-professional students. Notes that it is generally accepted that professional and graduate schools require students with good reading ability because of the quantity of material to be read. Presents standard scores, percentile ranks, and stanine scores as revised norms based on test…

  7. "Passageless" Administration of the Nelson-Denny Reading Comprehension Test: Associations with IQ and Reading Skills

    ERIC Educational Resources Information Center

    Ready, Rebecca E.; Chaudhry, Maheen F.; Schatz, Kelly C.; Strazzullo, Sarah

    2013-01-01

    There are few tests that assess reading comprehension in adults, but these tests are needed for a comprehensive assessment of reading disorders (RD). "The Nelson-Denny Reading Test" (NDRT) has a long-passage reading comprehension component that can be used with adolescents and adults. A problem with the NDRT is that reading comprehension test…

  8. Coherent Backscattering: Conceptions and Misconceptions (Reply to Comments by Bruce W. Hapke and Robert M. Nelson)

    NASA Technical Reports Server (NTRS)

    Tishkovets, Victor P.; Mishchenko, Michael

    2010-01-01

    Although the note by Hapke and Nelson has virtually no relevance to our original publication, it contains a number of statements that are misleading and/or wrong. We, therefore, use this opportunity to dispel several profound misconceptions that continue to hinder the progress in remote sensing of planetary surfaces.

  9. U.S. Rep. William Nelson drinking tea from shuttle beverage container

    NASA Technical Reports Server (NTRS)

    1985-01-01

    U.S. Rep. William Nelson of Florida tries drinking tea from a straw-equipped beverage dispenser in JSC's life sciences laboratory during a space food orientation session. The congressman is in early stages of training for a position on the STS 61-C mission.

  10. "Finding Useful Questions: On Bayesian Diagnosticity, Probability, Impact, and Information Gain": Correction to Nelson (2005)

    ERIC Educational Resources Information Center

    Nelson, Jonathan D.

    2007-01-01

    Reports an error in "Finding Useful Questions: On Bayesian Diagnosticity, Probability, Impact, and Information Gain" by Jonathan D. Nelson (Psychological Review, 2005[Oct], Vol 112[4], 979-999). In Table 13, the data should indicate that 7% of females had short hair and 93% of females had long hair. The calculations and discussion in the article…

  11. Celebrating the Hero in All of Us: An Interview with Kadir Nelson

    ERIC Educational Resources Information Center

    Sableski, Mary-Kate; Arnold, Jackie Marshall; Adomat, Donna Sayers

    2015-01-01

    Books provide an opportunity through which children can learn what it means to be in the world and to respond flexibly and creatively to a diverse range of situations. Author/illustrator Kadir Nelson creates books that provide these opportunities for readers of all ages. A dominant theme in current conversations surrounding children's literature…

  12. Effect of redox conditions on bacterial and fungal biomass and carbon dioxide production in Louisiana coastal swamp forest sediment.

    PubMed

    Seo, Dong Cheol; DeLaune, Ronald D

    2010-08-01

    Fungal and bacterial carbon dioxide (CO2) production/emission was determined under a range of redox conditions in sediment from a Louisiana swamp forest used for wastewater treatment. Sediment was incubated in microcosms at 6 Eh levels (-200, -100, 0, +100, +250 and +400 mV) covering the anaerobic range found in wetland soil and sediment. Carbon dioxide production was determined by the substrate-induced respiration (SIR) inhibition method. Cycloheximide (C15H23NO4) was used as the fungal inhibitor and streptomycin (C21H39N7O12) as the bacterial inhibitor. Under moderately reducing conditions (Eh > +250 mV), fungi contributed more than bacteria to the CO2 production. Under highly reducing conditions (Eh < or = 0 mV), bacteria contributed more than fungi to the total CO2 production. The fungi/bacteria (F/B) ratios varied between 0.71-1.16 for microbial biomass C, and 0.54-0.94 for microbial biomass N. Under moderately reducing conditions (Eh > or = +100 mV), the F/B ratios for microbial biomass C and N were higher than that for highly reducing conditions (Eh < or = 0 mV). In moderately reducing conditions (Eh > or = +100 mV), the C/N microbial biomass ratio for fungi (C/N: 13.54-14.26) was slightly higher than for bacteria (C/N: 9.61-12.07). Under highly reducing redox conditions (Eh < or = 0 mV), the C/N microbial biomass ratio for fungi (C/N: 10.79-12.41) was higher than for bacteria (C/N: 8.21-9.14). For bacteria and fungi, the C/N microbial biomass ratios under moderately reducing conditions were higher than that in highly reducing conditions. Fungal CO2 production from swamp forest could be of greater ecological significance under moderately reducing sediment conditions contributing to the greenhouse effect (GHE) and the global warming potential (GWP). However, increases in coastal submergence associated with global sea level rise and resultant decrease in sediment redox potential from increased flooding would likely shift CO2 production to bacteria rather than

  13. Effects of warming conditions in eastern North American forests on red-backed salamander morphology.

    PubMed

    Gibbs, James P; Karraker, Nancy E

    2006-06-01

    Several studies have reported climate-associated changes in phenotypically plastic traits of amphibians, yet it remains unknown whether amphibians can manifest an evolutionary response to global climate change at the rate and magnitude that it is occurring. To assess this issue, we examined temporal change in the morphology of the red-backed salamander (Plethodon cinereus), a small, abundant woodland salamander distributed widely in eastern North America with two distinct morphotypes: striped individuals associated with cooler microclimates and unstriped individuals associated with warmer microclimates. We compiled morph frequencies for 50,960 individual salamanders from 558 sites as recorded in the published literature and in unpublished field notes of herpetologists between 1908 and 2004. We observed that striping probability increased with increasing latitude, longitude, and elevation and decreased (from 80% to 74% range wide) with time. The combined forces of regional climate warming and, particularly, forest disturbance have evidently been sufficient to cause morphological evolution in this amphibian over the last century.

  14. Present condition of the coniferous undergrowth of forest-tundra ecotone of North-Chuya ridge (Central Altai)

    NASA Astrophysics Data System (ADS)

    Propastilova, Olga; Timoshok, Elena

    2010-05-01

    Investigations of high-mountain regions which are characterized by extreme climate conditions are of current importance since the response of environmental ecosystems to climate changes is clearly expressed there. The work presented was performed on the territory of two mountain glacial basins located on the northern macroslope of North-Chuya ridge (Russia, Central Altai). High-mountain vegetation of the area being considered didn't undergo an anthropogenic impact. It should be noted that investigations of coniferous undergrowth of forest-tundra ecotone of Aktru and Korumdu mountain glacial basins (2200-2500 m ab. s.l.) haven't been conducted before. A climatic representativeness of Aktru basin was proved by numerous data (Tronov et all, 1965, Sevastianov, 1998). The goal of the work was studying of condition and adaptations of young Pinus sibirica Du Tour and Larix sibirica Ledeb. to forest-tundra ecotone conditions. These species form the treeline on many ridges of Central Altai (Kuminova, 1960), including North-Chuya (Timoshok, 2004). It is shown that the number of young Siberian stone pines and larches in the forest-tundra ecotone is not big, Siberian stone pine being found more often than larch. A considerable quantity of young Siberian stone pines grows in sheltered sites (near big stones, boulders, stumps, etc.). During the research period dead young trees have been found in single cases. The maximum percentage of Siberian stone pine trees (42.4%) growing in sheltered sites was registered in Aktru basin on the east-southeast slope whereas on the west-northwest slope the maximum percentage of Siberian stone pines growing in clusters has been revealed (34.4%). Also on the west-northwest slope the maximum quantity of Siberian stone pines that changed their terminal shoots have been found (62.5%). During the investigation young trees with signs of diseases were registered. Chermes (Pineus cembrae Chol.) has been found on shoots and needles. On the west

  15. The role of fleshy pericarp in seed germination and dispersal under flooded conditions in three wetland forest species

    NASA Astrophysics Data System (ADS)

    Mora, Juan P.; Smith-Ramírez, Cecilia; Zúñiga-Feest, Alejandra

    2013-01-01

    In flooded habitats, inundations affect important forest regeneration processes, such as seed dispersal and germination. The main seed dispersal mechanism used by species in Austral South American temperate swamp and riparian forests is endozoochory, which releases seeds from the fleshy pericarp. Endozoochory could be favorable or unfavorable in wetland habitats, since this mechanism exposes seeds directly to water and can, in some cases, be detrimental to germination. In this study, we studied whether or not the fleshy pericarp favors germination after the flooding period's end. Furthermore, we quantified if the number of days which the fruit was found to be floating related to its germination success. We used the seeds of three common fleshy fruit species of flooded habitats from southern Chile, the trees Luma apiculata and Rhaphithamnus spinosus, and the vine Luzuriaga radicans. We simulated flooding periods of 7, 15, 30 and 45 days submerging seeds, with and without pericarps, in water. We found that the pericarp's presence significantly increased Luma's germination success and significantly decreased that of Luzuriaga. The germination of Rhaphithamnus was low after periods of flooding in both seed treatments, with no significant differences found between them. The fruits could float for an average of one to four weeks, depending on the species, which did not relate to their germination success. These results show that germination was affected by the presence of fleshy pericarps in flooded conditions and furthermore, that flotation allows for hydrochory from one week to one month. We suggest that in swamp forests multiple seed dispersal mechanisms are advantageous, especially for fleshy-fruited species.

  16. Sun/shade conditions affect recruitment and local adaptation of a columnar cactus in dry forests

    PubMed Central

    Miranda-Jácome, Antonio; Montaña, Carlos; Fornoni, Juan

    2013-01-01

    Background and Aims Facilitation among plants in water-limited environments (i.e. where evapotranspiration overcomes the availability of water during the growing season) has been considered a local adaptation to water and light conditions. Among cacti, early life-history stages can benefit from the facilitative effects of nurse plants that reduce solar radiation and water stress. However, whether light condition itself acts as an agent of selection through facilitation remains untested. The aim of this study was to determine (1) whether light conditions affect seedling recruitment, (2) whether the positive effect of shade on seedling recruitment is more intense under more stressful conditions and (3) whether shade condition (facilitation) reduces the magnitude of local adaptation on seedling recruitment relative to full sunlight conditions. Methods A reciprocal transplant experiment, coupled with the artificial manipulation of sun/shade conditions, was performed to test for the effects of local adaptation on germination, seedling survival and growth, using two demes of the columnar cactus Pilosocereus leucocephalus, representing different intensities of stressful conditions. Key Results Full sunlight conditions reduced recruitment success and supported the expectation of lower recruitment in more stressful environments. Significant local adaptation was mainly detected under full sunlight conditions, indicating that this environmental factor acts as an agent of selection at both sites. Conclusions The results supported the expectation that the magnitude of local adaptation, driven by the effects of facilitative nurse plants, is less intense under reduced stressful conditions. This study is the first to demonstrate that sun/shade conditions act as a selective agent accounting for local adaptation in water-limited environments, and that facilitation provided by nurse plants in these environments can attenuate the patterns of local adaptation among plants benefiting

  17. Global Climate Model Simulated Hydrologic Droughts and Floods in the Nelson-Churchill Watershed

    NASA Astrophysics Data System (ADS)

    Vieira, M. J. F.; Stadnyk, T. A.; Koenig, K. A.

    2014-12-01

    There is uncertainty surrounding the duration, magnitude and frequency of historical hydroclimatic extremes such as hydrologic droughts and floods prior to the observed record. In regions where paleoclimatic studies are less reliable, Global Climate Models (GCMs) can provide useful information about past hydroclimatic conditions. This study evaluates the use of Coupled Model Intercomparison Project 5 (CMIP5) GCMs to enhance the understanding of historical droughts and floods across the Canadian Prairie region in the Nelson-Churchill Watershed (NCW). The NCW is approximately 1.4 million km2 in size and drains into Hudson Bay in Northern Manitoba, Canada. One hundred years of observed hydrologic records show extended dry and wet periods in this region; however paleoclimatic studies suggest that longer, more severe droughts have occurred in the past. In Manitoba, where hydropower is the primary source of electricity, droughts are of particular interest as they are important for future resource planning. Twenty-three GCMs with daily runoff are evaluated using 16 metrics for skill in reproducing historic annual runoff patterns. A common 56-year historic period of 1950-2005 is used for this evaluation to capture wet and dry periods. GCM runoff is then routed at a grid resolution of 0.25° using the WATFLOOD hydrological model storage-routing algorithm to develop streamflow scenarios. Reservoir operation is naturalized and a consistent temperature scenario is used to determine ice-on and ice-off conditions. These streamflow simulations are compared with the historic record to remove bias using quantile mapping of empirical distribution functions. GCM runoff data from pre-industrial and future projection experiments are also bias corrected to obtain extended streamflow simulations. GCM streamflow simulations of more than 650 years include a stationary (pre-industrial) period and future periods forced by radiative forcing scenarios. Quantile mapping adjusts for magnitude

  18. Evaluation of the airborne imaging spectrometer for remote sensing of forest stand conditions

    NASA Technical Reports Server (NTRS)

    Olson, Charles E., Jr.

    1986-01-01

    Five pairs of plots were established in forest stands with one of each pair trenched and covered to prevent precipitation from reaching the tree roots. High winds and falling limbs destroyed the covers on three of the plots. The two remaining plots were in a red pine plantation and in a natural stand of sugar maple. Trees in both plots developed levels of moisture stress more than nine bars higher than control trees on the dates of overflights with the Airborne Imaging Spectrometer (AIS) and the Collins' Airborne Spectroradiometer (CAS). Hemispherical reflectance from stressed and control trees was measured with a Beckman DK2A spectrophotometer. On the day of the AIS overflight, stressed maple foliage was less reflective than the control from 1000 to 1300 nm, but more reflective at wavelengths longer than 1300 nm. Pine foliage was less reflective than the control from 1000 to 1600 nm, but the difference was small at wavelengths longer than 1350 nm. AIS data collected showed brightness values for both maple and pine to be lower than for the controls from 1000 to 1300 nm. CAS data were used to determine the gain in species identification accuracy obtainable with high spectral resolution data.

  19. Petroleum hydrocarbon contamination in Nelson Lagoon, Alaska, sampling three different matrices.

    PubMed

    Lance, Ellen W; Matz, Angela C; Reeves, Mari K; Verbrugge, Lori A

    2012-10-01

    Polycyclic aromatic hydrocarbon (PAH) levels were measured in sediments, bivalves and semi-permeable membrane devices (SPMDs) in the relatively pristine marine environment of Nelson Lagoon, Alaska. Most PAH levels in Nelson Lagoon were low, and similar to global background concentrations. Sampling media type can significantly influence conclusions of PAH contamination in the environment. Concentration of a broad size range of PAHs was observed in the tissues of blue mussels (Mytilus edulis). SPMDs collected some two- to three-ring PAHs from the dissolved water phase, while sediments collected five- to six-ring PAHs that were likely adsorbed onto particulate matter. Benzo(a)pyrene, a potent carcinogen, was found in mussels at levels similar to more industrialized harbors in Alaska.

  20. The struggle for Sunday lunch: gastropolitics in the life of Nelson Mandela.

    PubMed

    Trapido, Anna

    2011-01-01

    This paper explores the political, economic, and social life of Nelson Mandela through his food choices from 1918 to the present. A description of the minutiae of one particular 1950s Sunday lunch is used to examine the broader role of first colonial and later apartheid legislation in determining the dietary choices and options of South Africans past and present. How such policies shaped attitudes and access to Nelson Mandela’s ancestral Xhosa cuisine is assessed. The long-term cultural, economic, and political impact of a lack of access to core indigenous African ingredients is evaluated. Most of all this paper offers a snapshot portrayal of two families (one white, one black) trying to sustain a normal friendship within a grossly abnormal society.

  1. The struggle for Sunday lunch: gastropolitics in the life of Nelson Mandela.

    PubMed

    Trapido, Anna

    2011-01-01

    This paper explores the political, economic, and social life of Nelson Mandela through his food choices from 1918 to the present. A description of the minutiae of one particular 1950s Sunday lunch is used to examine the broader role of first colonial and later apartheid legislation in determining the dietary choices and options of South Africans past and present. How such policies shaped attitudes and access to Nelson Mandela’s ancestral Xhosa cuisine is assessed. The long-term cultural, economic, and political impact of a lack of access to core indigenous African ingredients is evaluated. Most of all this paper offers a snapshot portrayal of two families (one white, one black) trying to sustain a normal friendship within a grossly abnormal society. PMID:21591311

  2. The man who loved flies: a biographical profile of Nelson Papavero .

    PubMed

    Klassa, Bruna; Santos, Charles Morphy D

    2014-04-29

    Nelson Papavero is one of the major Brazilian zoologists. His contribution to the field began in the second half of the twentieth century, when he started publishing in the areas of entomology, systematics, biogeography, and history of science, while working at graduate courses and training teachers and students. Papavero was one of the earliest Brazilian advocates of Hennig's phylogenetic systematics. In his entomological work, his first widely recognised works were the Catalogue of South American Diptera and his essays on the history of Neotropical Dipterology. Papavero's greatest contribution however, is in his Special Courses on Zoological Systematics, as well as his numerous administrative positions during his academic career. All these were fundamental to the development of zoology and comparative biology in Brazil and other Latin American countries. Here we present a biography of Nelson Papavero, along with several personal anecdotes, and his role in the development of Brazilian biological systematics over the last 50 years. 

  3. Development of a mixed shrub-tanoak-douglas-fir community in a treated and untreated condition. Forest Service research paper

    SciTech Connect

    McDonald, P.M.; Fiddler, G.O.

    1996-08-01

    On a medium site in northern California, a tanoak-mixed shrub community was given several treatments (manual release two and three times, a combination chainsaw and cut surface herbicide treatment, two foliar herbicides, and a tank mix of the two herbicides) to study its development in both a natural (control) and treated condition. The herbicides were 2,4-D, Garlon 3A, and Garlon 4, each applied two times. Survival of planted Douglas-fir seedlings was recorded for 11 years and growth was quantified for 9 years after the last treatment application. In addition to Douglas-fir, data are presented individually for the two most abundant species (tanoak and snowbrush), for greenleaf manzanita, and for the hardwood tree and shrubs combined. The treatment response data, cost information, and plant community relationships provides the forest land manager with knowledge on how to attain some specific plant communities in the future, and their developmental potentials.

  4. Sustaining the Landscape: A Method for Comparing Current and Desired Future Conditions of Forest Ecosystems in the North Cumberland Plateau and Mountains

    SciTech Connect

    Druckenbrod, D.L.

    2004-12-22

    This project initiates an integrated-landscape conservation approach within the Northern Cumberlands Project Area in Tennessee and Kentucky. The mixed mesophytic forests within the Cumberland Plateau and Mountains are among the most diverse in North America; however, these forests have been impacted by and remain threatened from changes in land use across this landscape. The integrated-landscape conservation approach presented in this report outlines a sequence of six conservation steps. This report considers the first three of these steps in two, successive stages. Stage 1 compares desired future conditions (DFCs) and current prevailing conditions (CPCs) at the landscape-scale utilizing remote sensing imagery, remnant forests, and descriptions of historical forest types within the Cumberland Plateau. Subsequently, Stage 2 compares DFCs and CPCs for at-risk forest types identified in Stage 1 utilizing structural, compositional, or functional attributes from USFS Forest Inventory and Analysis data. Ecological indicators will be developed from each stage that express the gaps between these two realizations of the landscape. The results from these first three steps will directly contribute to the final three steps of the integrated-landscape conservation approach by providing guidance for the generation of new conservation strategies in the Northern Cumberland Plateau and Mountains.

  5. Preliminary report on the Nelson and Radovan copper prospects, Nizina district, Alaska

    USGS Publications Warehouse

    Sainsbury, C.J.

    1952-01-01

    Renewed copper exploration by Alaska Copper Mines, Incorporated, at the Nelson and Radovan prospects, Nizina district, Alaska, led the Geological Survey in 1951 to map in detail the Nelson fault block, and to re-examine the old workings. In addition, two new prospects were studied. The Nelson fault block is cut by many dominantly strike-slip faults of small displacement, and by bedding faults. Slickensided chalcocite shows post-mineral movement, and chalcocite veinlet in a filled solution cavity indicates that some of the chalcocite is secondary, perhaps very recent. Structural relations indicate two overthrust faults cut the block. The Radovan Greenstone prospect shows massive chalcocite, up to 3 feet wide, in a silicified, epidotized fault zone in the Nikolai greenstone. Ore indicated by surface exposures may amount to 450 tons of chalcocite. The Radovan Low-Contact prospect is on a continuation of the same fault approximately 3 miles southwest of the Greenstone prospect, and 150 feet above the contact of the Nikolai greenstone and the overlying Chitistone limestone. Limonite staining is widespread in bedding planes and small faults near the fault zone; mineralization in the fault zone consists of pyrite, chalcocite, bornite, malachite, realgar, orpiment and stibnite. The sulphides in the fault zone, plus the widespread silicification and epidotization indicate a strong zone of hydrothermal activity which merits extensive prospecting.

  6. Molecular characterization of forest soil based Paenibacillus elgii and optimization of various culture conditions for its improved antimicrobial activity.

    PubMed

    Kumar, S N; Jacob, Jubi; Reshma, U R; Rajesh, R O; Kumar, B S D

    2015-01-01

    Microorganisms have provided a bounty of bioactive secondary metabolites with very exciting biological activities such as antibacterial, antifungal antiviral, and anticancer, etc. The present study aims at the optimization of culture conditions for improved antimicrobial production of Paenibacillus elgii obtained from Wayanad forest of Western Ghats region of Kerala, India. A bacterial strain isolated from the Western Ghats forest soil of Wayanad, Kerala, India was identified as P. elgii by 16S rRNA gene sequencing. P. elgii recorded significant board spectrum activity against all human and plant pathogenic microorganism tested except Candida albicans. It has been well known that even minor variations in the fermentation medium may impact not only the quantity of desired bioactive metabolites but also the general metabolic profile of the producing microorganisms. Thus, further studies were carried out to assess the impact of medium components on the antimicrobial production of P. elgii and to optimize an ideal fermentation medium to maximize its antimicrobial production. Out of three media [nutrient broth (NA), Luria broth (LB) and Trypticase soy broth (TSB)] used for fermentation, TSB medium recorded significant activity. Glucose and meat peptone were identified as the best carbon and nitrogen sources, which significantly affected the antibiotic production when supplemented with TSB medium. Next the effect of various fermentation conditions such as temperature, pH, and incubation time on the production of antimicrobial compounds was studied on TSB + glucose + meat peptone and an initial pH of 7 and a temperature of 30°C for 3 days were found to be optimum for maximum antimicrobial production. The results indicate that medium composition in the fermentation media along with cultural parameters plays a vital role in the enhanced production of antimicrobial substances.

  7. Molecular characterization of forest soil based Paenibacillus elgii and optimization of various culture conditions for its improved antimicrobial activity.

    PubMed

    Kumar, S N; Jacob, Jubi; Reshma, U R; Rajesh, R O; Kumar, B S D

    2015-01-01

    Microorganisms have provided a bounty of bioactive secondary metabolites with very exciting biological activities such as antibacterial, antifungal antiviral, and anticancer, etc. The present study aims at the optimization of culture conditions for improved antimicrobial production of Paenibacillus elgii obtained from Wayanad forest of Western Ghats region of Kerala, India. A bacterial strain isolated from the Western Ghats forest soil of Wayanad, Kerala, India was identified as P. elgii by 16S rRNA gene sequencing. P. elgii recorded significant board spectrum activity against all human and plant pathogenic microorganism tested except Candida albicans. It has been well known that even minor variations in the fermentation medium may impact not only the quantity of desired bioactive metabolites but also the general metabolic profile of the producing microorganisms. Thus, further studies were carried out to assess the impact of medium components on the antimicrobial production of P. elgii and to optimize an ideal fermentation medium to maximize its antimicrobial production. Out of three media [nutrient broth (NA), Luria broth (LB) and Trypticase soy broth (TSB)] used for fermentation, TSB medium recorded significant activity. Glucose and meat peptone were identified as the best carbon and nitrogen sources, which significantly affected the antibiotic production when supplemented with TSB medium. Next the effect of various fermentation conditions such as temperature, pH, and incubation time on the production of antimicrobial compounds was studied on TSB + glucose + meat peptone and an initial pH of 7 and a temperature of 30°C for 3 days were found to be optimum for maximum antimicrobial production. The results indicate that medium composition in the fermentation media along with cultural parameters plays a vital role in the enhanced production of antimicrobial substances. PMID:26539188

  8. Molecular characterization of forest soil based Paenibacillus elgii and optimization of various culture conditions for its improved antimicrobial activity

    PubMed Central

    Kumar, S. N.; Jacob, Jubi; Reshma, U. R.; Rajesh, R. O.; Kumar, B. S. D.

    2015-01-01

    Microorganisms have provided a bounty of bioactive secondary metabolites with very exciting biological activities such as antibacterial, antifungal antiviral, and anticancer, etc. The present study aims at the optimization of culture conditions for improved antimicrobial production of Paenibacillus elgii obtained from Wayanad forest of Western Ghats region of Kerala, India. A bacterial strain isolated from the Western Ghats forest soil of Wayanad, Kerala, India was identified as P. elgii by 16S rRNA gene sequencing. P. elgii recorded significant board spectrum activity against all human and plant pathogenic microorganism tested except Candida albicans. It has been well known that even minor variations in the fermentation medium may impact not only the quantity of desired bioactive metabolites but also the general metabolic profile of the producing microorganisms. Thus, further studies were carried out to assess the impact of medium components on the antimicrobial production of P. elgii and to optimize an ideal fermentation medium to maximize its antimicrobial production. Out of three media [nutrient broth (NA), Luria broth (LB) and Trypticase soy broth (TSB)] used for fermentation, TSB medium recorded significant activity. Glucose and meat peptone were identified as the best carbon and nitrogen sources, which significantly affected the antibiotic production when supplemented with TSB medium. Next the effect of various fermentation conditions such as temperature, pH, and incubation time on the production of antimicrobial compounds was studied on TSB + glucose + meat peptone and an initial pH of 7 and a temperature of 30°C for 3 days were found to be optimum for maximum antimicrobial production. The results indicate that medium composition in the fermentation media along with cultural parameters plays a vital role in the enhanced production of antimicrobial substances. PMID:26539188

  9. Equilibrium and kinetics in metamorphism of pelites in the Nelson aureole, British Columbia

    NASA Astrophysics Data System (ADS)

    Pattison, D. R. M.

    2009-04-01

    The distribution of metapelitic mineral assemblages in the Nelson aureole, British Columbia, generally conforms to what is predicted from phase equilibria. However, in detail, the mineral textures, mineral compositions and zoning, and sequence and spacing of isograds do not. Two of the main disequilibrium features in the aureole are: (1) delay in the onset and progress of several reactions, ie, thermal overstepping; and (2) unreactivity of staurolite and especially garnet porphyroblasts when they are reactants in higher grade reactions. The thermal overstepping is ascribed primarily to difficulty of nucleation of the product porphyroblasts and sluggishness of dissolution of reactant porphyroblasts required for product mineral growth. The extent to which these barriers to nucleation and growth delay the onset of reaction is related to the reaction affinity of each reaction, which for thermally activated reactions is, in turn, related to the entropy change of the reaction. For a given overstep in temperature, reactions that release large quatities of H2O, such as chlorite-consuming reactions, have a high reaction affinity compared to those which release little or no H2O, such as the chlorite-free staurolite-consuming reaction. Thermal overstepping is consequently expected to be less for the former than for the latter, as was observed in the aureole where ca. 30 °C overstepping was required for garnet growth from a muscovite+chlorite-bearing precursor and ca. 70 °C overstepping was required for growth of Al2SiO5 from a staurolite-bearing, chlorite-free precursor. In all cases reaction progress was strongly influenced by presence or absence of fluid, with fluid presence dramatically lowering kinetic barriers to nucleation and growth, and therefore thermal overstepping. Textural features of rocks from the nearly coincident garnet, staurolite and andalusite isograds are suggestive of a fluid-catalyzed ‘cascade effect' in which reaction took place rapidly and several

  10. Tracing Nitrogen Sources in Forested Catchments Under Varying Flow Conditions: Seasonal and Event Scale Patterns

    NASA Astrophysics Data System (ADS)

    Sebestyen, S. D.; Shanley, J. B.; Boyer, E. W.; Kendall, C.

    2004-12-01

    Our ability to assess how stream nutrient concentrations respond to biogeochemical transformations and stream flow dynamics is often limited by datasets that do not include all flow conditions that occur over event, monthly, seasonal, and yearly time scales. At the Sleepers River Research Watershed in northeastern Vermont, USA, nitrate, DOC (dissolved organic carbon), and major ion concentrations were measured on samples collected over a wide range of flow conditions from summer 2002 through summer 2004. Nutrient flushing occurred at the W-9 catchment and high-frequency sampling revealed critical insights into seasonal and event-scale controls on nutrient concentrations. In this seasonally snow-covered catchment, the earliest stage of snowmelt introduced nitrogen directly to the stream from the snowpack. As snowmelt progressed, the source of stream nitrate shifted to flushing of soil nitrate along shallow subsurface flow paths. In the growing season, nitrogen flushing to streams varied with antecedent moisture conditions. More nitrogen was available to flush to streams when antecedent moisture was lowest, and mobile nitrogen stores in the landscape regenerated under baseflow conditions on times scales as short as 7 days. Leaf fall was another critical time when coupled hydrological and biogeochemical processes controlled nutrient fluxes. With the input of labile organic carbon from freshly decomposing leaves, nitrate concentrations declined sharply in response to in-stream immobilization or denitrification. These high-resolution hydrochemical data from multiple flow regimes are identifying "hot spots" and "hot moments" of biogeochemical and hydrological processes that control nutrient fluxes in streams.

  11. Random forest models for the probable biological condition of streams and rivers in the USA

    EPA Science Inventory

    The National Rivers and Streams Assessment (NRSA) is a probability based survey conducted by the US Environmental Protection Agency and its state and tribal partners. It provides information on the ecological condition of the rivers and streams in the conterminous USA, and the ex...

  12. Meteorological factors and air pollution in Lithuanian forests: possible effects on tree condition.

    PubMed

    Ozolincius, Remigijus; Stakenas, Vidas; Serafinaviciute, Brigita

    2005-10-01

    This study investigates changes in tree condition and environmental factors in Lithuania during the active growing season in 1991-2001. The average crown defoliation and the proportion of healthy trees of Pinus sylvestris, Picea abies, Betula sp., Fraxinus excelsior, Alnus incana, Alnus glutinosa, Populus tremula, and Quercus robur, meteorological (average temperature, amount of precipitation, hydrothermal coefficient) and air pollution data (acidity of precipitation, concentrations of SO2, NO2 and exposure of O3) were analysed. During the period 1991-2001 the condition of Pinus sylvestris, Populus tremula showed a tendency of improvement, while defoliation of Fraxinus excelsior significantly increased. The proportion of healthy trees correlated well with the average temperature and O3 (AOT40), while defoliation correlated well with the acidity of precipitation and the concentrations of SO2 and NO2. Deciduous species appeared to be more sensitive to O3 exposure and conifers to the concentrations of SO2 and NO2.

  13. Pathogenicity of Beauveria bassiana isolated from Moroccan Argan forests soil against larvae of Ceratitis capitata (Diptera: Tephritidae) in laboratory conditions.

    PubMed

    Imoulan, Abdessamad; Elmeziane, Abdellatif

    2014-03-01

    The Mediterranean fruit fly, Ceratitis capitata Wiedemann (Diptera: Tephritidae), is the major tephritid pest in Morocco. This pest survives in Moroccan forests Argania spinosa and continually invades the nearest agricultural areas. Entomopathogenic fungi are an interesting tool for fruit fly control and hold a useful alternative to conventional insecticides. However, primary selection of effective pathogens should be taken in laboratory condition prior to applying them in the field. Here, we used third late instar larvae of C. capitata to investigate the effectiveness of 15 local Beauveria bassiana isolates. Results showed that all isolates were able to infect the larval stage, producing a large mortality rate in puparia ranging from 65 to 95 % and caused significant reduction in adult emergence. The fungal treatments revealed that the mycosis occurred also in adults escaping infection as pupariating larvae. The percentage of mycosed puparia was highest in strain TAM6.2 (95 %) followed by ERS4.16 (90 %), therefore they were the most virulent. Median lethal concentration (LC₅₀) was studied for five isolates at four concentrations ranging from 10⁵ to 10⁸ conidia ml⁻¹. The results showed that the slopes of regression lines for B. bassiana ERS4.16 (slope = 0.386) and TAM6.2 (slope = 0.41) were the most important and had the lowest LC₅₀ values (2.85 × 10³ and 3.16 × 10³ conidia ml⁻¹ respectively). This investigation suggests that the soil of Argan forests contains pathogenic B. bassiana isolates and highlights for the first time their potential as biological control toward C. capitata larval stage in Morocco. PMID:24122125

  14. Pathogenicity of Beauveria bassiana isolated from Moroccan Argan forests soil against larvae of Ceratitis capitata (Diptera: Tephritidae) in laboratory conditions.

    PubMed

    Imoulan, Abdessamad; Elmeziane, Abdellatif

    2014-03-01

    The Mediterranean fruit fly, Ceratitis capitata Wiedemann (Diptera: Tephritidae), is the major tephritid pest in Morocco. This pest survives in Moroccan forests Argania spinosa and continually invades the nearest agricultural areas. Entomopathogenic fungi are an interesting tool for fruit fly control and hold a useful alternative to conventional insecticides. However, primary selection of effective pathogens should be taken in laboratory condition prior to applying them in the field. Here, we used third late instar larvae of C. capitata to investigate the effectiveness of 15 local Beauveria bassiana isolates. Results showed that all isolates were able to infect the larval stage, producing a large mortality rate in puparia ranging from 65 to 95 % and caused significant reduction in adult emergence. The fungal treatments revealed that the mycosis occurred also in adults escaping infection as pupariating larvae. The percentage of mycosed puparia was highest in strain TAM6.2 (95 %) followed by ERS4.16 (90 %), therefore they were the most virulent. Median lethal concentration (LC₅₀) was studied for five isolates at four concentrations ranging from 10⁵ to 10⁸ conidia ml⁻¹. The results showed that the slopes of regression lines for B. bassiana ERS4.16 (slope = 0.386) and TAM6.2 (slope = 0.41) were the most important and had the lowest LC₅₀ values (2.85 × 10³ and 3.16 × 10³ conidia ml⁻¹ respectively). This investigation suggests that the soil of Argan forests contains pathogenic B. bassiana isolates and highlights for the first time their potential as biological control toward C. capitata larval stage in Morocco.

  15. The effect of climate and soil conditions on tree species turnover in a Tropical Montane Cloud Forest in Costa Rica.

    PubMed

    Häger, Achim

    2010-12-01

    On a global level, Tropical Montane Cloud Forests constitute important centers of vascular plant diversity. Tree species turnover along environmental gradients plays an important role in larger scale diversity patterns in tropical mountains. This study aims to estimate the magnitude of beta diversity across the Tilardn mountain range in North-Western Costa Rica, and to elucidate the impact of climate and soil conditions on tree species turnover at a local scale. Seven climate stations measuring rainfall, horizontal precipitation (clouds and wind-driven rain) and temperatures were installed along a 2.5km transect ranging from 1200 m.a.s.l. on the Atlantic to 1200 m.a.s.l. on the Pacific slope. The ridge top climate station was located at 1500 m.a.s.l. Climate data were recorded from March through December 2003. Additionally, seven 0.05 ha plots were established. On all plots soil moisture was monitored for one year, furthermore soil type and soil chemistry were assessed. Woody plants with a diameter at breast height (dbh) > or = 5 cm were identified to species. Species' distributions were explored by feeding pairwise Serensen measures between plots into a Principal Component Analysis. Relationships between floristic similarity and environmental variables were analyzed using Mantel tests. Pronounced gradients in horizontal precipitation, temperatures and soil conditions were found across the transect. In total, 483 woody plants were identified, belonging to 132 species. Environmental gradients were paralleled by tree species turnover; the plots could be divided in three distinctive floristic units which reflected different topographic positions on the transect (lower slopes, mid slopes and ridge). Most notably there was a complete species turnover between the ridge and the lower Pacific slope. Floristic similarity was negatively correlated with differences in elevation, horizontal precipitation, temperatures and soil conditions between plots. It is suggested that

  16. Modeling soil heating and moisture transport under extreme conditions: Forest fires and slash pile burns

    NASA Astrophysics Data System (ADS)

    Massman, W. J.

    2012-10-01

    Heating any soil during a sufficiently intense wildfire or prescribed burn can alter it irreversibly, causing many significant, long-term biological, chemical, and hydrological effects. Given the climate-change-driven increasing probability of wildfires and the increasing use of prescribed burns by land managers, it is important to better understand the dynamics of the coupled heat and moisture transport in soil during these extreme heating events. Furthermore, improved understanding and modeling of heat and mass transport during extreme conditions should provide insights into the associated transport mechanisms under more normal conditions. The present study describes a numerical model developed to simulate soil heat and moisture transport during fires where the surface heating often ranges between 10,000 and 100,000 W m-2 for several minutes to several hours. Basically, the model extends methods commonly used to model coupled heat flow and moisture evaporation at ambient conditions into regions of extreme dryness and heat. But it also incorporates some infrequently used formulations for temperature dependencies of the soil specific heat, thermal conductivity, and the water retention curve, as well as advective effects due to the large changes in volume that occur when liquid water is rapidly volatilized. Model performance is tested against laboratory measurements of soil temperature and moisture changes at several depths during controlled heating events. Qualitatively, the model agrees with the laboratory observations, namely, it simulates an increase in soil moisture ahead of the drying front (due to the condensation of evaporated soil water at the front) and a hiatus in the soil temperature rise during the strongly evaporative stage of the soil drying. Nevertheless, it is shown that the model is incapable of producing a physically realistic solution because it does not (and, in fact, cannot) represent the relationship between soil water potential and soil

  17. Soil heating and evaporation under extreme conditions: Forest fires and slash pile burns

    NASA Astrophysics Data System (ADS)

    Massman, W. J.

    2011-12-01

    Heating any soil during a sufficiently intense wild fire or prescribed burn can alter soil irreversibly, resulting in many significant and well known, long term biological, chemical, and hydrological effects. To better understand how fire impacts soil, especially considering the increasing probability of wildfires that is being driven by climate change and the increasing use of prescribe burns by land managers, it is important to better understand the dynamics of the coupled heat and moisture transport in soil during these extreme heating events. Furthermore, improving understanding of heat and mass transport during such extreme conditions should also provide insights into the associated transport mechanisms under more normal conditions as well. Here I describe the development of a new model designed to simulate soil heat and moisture transport during fires where the surface heating often ranges between 10,000 and 100,000 Wm-2 for several minutes to several hours. Model performance is tested against laboratory measurements of soil temperature and moisture changes at several depths during controlled heating events created with an extremely intense radiant heater. The laboratory tests employed well described soils with well known physical properties. The model, on the other hand, is somewhat unusual in that it employs formulations for temperature dependencies of the soil specific heat, thermal conductivity, and the water retention curve (relation between soil moisture and soil moisture potential). It also employs a new formulation for the surface evaporation rate as a component of the upper boundary condition, as well as the Newton-Raphson method and the generalized Thomas algorithm for inverting block tri-diagonal matrices to solve for soil temperature and soil moisture potential. Model results show rapid evaporation rates with significant vapor transfer not only to the free atmosphere above the soil, but to lower depths of the soil, where the vapor re

  18. Selecting indicators of soil, microbial, and plant conditions to understand ecological changes in Georgia pine forests

    SciTech Connect

    Dale, Virginia H; Garten Jr, Charles T; Wolfe, Amy K; Sobek, Edward A

    2008-11-01

    Characterizing how resource use and management activities affect ecological conditions is necessary to document and understand anthropogenic changes in ecological systems. Resource managers on military installations have the delicate task of balancing the training needs of soldiers effectively with the need to maintain a high quality of ecological conditions. This study considers ways that ecological indicators can provide information on impacts that training has on environmental characteristics that occur at different scales and in different sectors of the environment. The characteristics examined include soil chemistry, soil microbes, and vegetation. A discriminant function analysis was conducted to determine whether ecological indicators could differentiate among different levels of military use. A combination of 10 indicators explained 90% of the variation among plots from five different military use levels. Results indicated that an appropriate suite of ecological indicators for military resource managers includes soil, microbial, and vegetation characteristics. Since many of these indicators are related, managers at this location potentially have freedom to choose indicators that are relatively easy to measure, without sacrificing information.

  19. Structuring expert input for a knowledge-based approach to watershed condition assessment for the Northwest Forest Plan, USA.

    PubMed

    Gordon, Sean N; Gallo, Kirsten

    2011-01-01

    Assessments of watershed condition for aquatic and riparian species often have to rely on expert opinion because of the complexity of establishing statistical relationships among the many factors involved. Such expert-based assessments can be difficult to document and apply consistently over time and space. We describe and reflect on the process of developing a computer-based decision support application from expert judgments for assessing aquatic and riparian conditions over the 100,000 km² managed by the US federal government under the Northwest Forest Plan. The decision support system helped structure and document the assessment process and provided consistency and transparency to the evaluation methodology. However, many decisions and trade-offs were required in the expert engagement and model-building processes. Knowledge elicitation in an interactive group had a number of benefits over nominal group or Delphi processes, but efficient knowledge capture required considerable planning and expertise in the subject matter and modeling process. Communicating model results for validation was problematic and only effectively accomplished via in-person workshops. The choice to use different expert groups for each biophysical province provided more opportunities for participation and promoted greater ownership in the assessment, but it also led to increased variation among the resulting model structures. We propose three possible approaches for better managing the consistency of assessment models when multiple expert groups are involved.

  20. Vegetation types and climate conditions reflected by the modern phytolith assemblages in the subalpine Dalaoling Forest Reserve, central China

    NASA Astrophysics Data System (ADS)

    Traoré, Djakanibé Désiré; Gu, Yansheng; Liu, Humei; Shemsanga, Ceven; Ge, Jiwen

    2015-06-01

    This research describes modern phytolith records and distributions from subalpine surface soils in the Dalaoling Forest Reserve, and reveals its implications for local climate conditions with respect to the altitude gradient. Well-preserved phytolith morpho-types, assemblages, and climatic indices were used to study the relationship between local vegetation and climate conditions. The phytolith classification system is mainly based on the characteristics of detailed morpho-types described for anatomical terms, which are divided into seven groups: long cells, short cells, bulliform cells, hair cells, pteridophyte type, broad-leaved type, and gymnosperm type. Phytoliths originating from the Poaceae are composed of Pooideae (rondel and trapeziform), Panicoideae (bilobate, cross, and polylobate), Chloridoideae (short/square saddle), and Bambusoideae (oblong concave saddle). Based on the altitudinal distribution of the phytolith assemblages and the indices of aridity (Iph), climate (Ic), and tree cover density (D/P), five phytolith assemblage zones have revealed the five types of climatic conditions ranging from 1,169 m to 2,005 m in turn: warm-wet, warm-xeric to warm-mesic, warm-xeric to cool-mesic, cool-xeric, and cool-mesic to cool-xeric. The Bambusoideae, Panicoideae, and Chloridoideae are the dominant vegetation at the lower-middle of the mountains, while Pooideae is mainly distributed in the higher mountains. The close relationship between phytolith assembleages and changes of altitude gradient suggest that vegetation distribution patterns and plant ecology in the Dalaoling mountains are controlled by temperature and humidity conditions. Our results highlight the importance of phytolith records as reliable ecoclimatic indicators for vegetation ecology in subtropical regions.

  1. Forest structure and landscape patterns in the subalpine lodgepole pine type: A procedure for quantifying past and present conditions. Forest Service general technical report

    SciTech Connect

    Arno, S.F.; Reinhardt, E.D.; Scott, J.H.

    1993-02-01

    The report presents a method of quantitatively representing the mosaic of stand types on a small landscape in the subalpine lodgepole pine forest type. The method utilizes macroplots placed systematically on a transect grid. Structure and composition of both current and past stands are inventoried. Procedures for data analysis and interpretation are illustrated for a lodgepole pine landscape in Montana.

  2. Wind-blown volcanic ash in forest and agricultural locations as related to meteorological conditions

    NASA Astrophysics Data System (ADS)

    Fowler, W. B.; Lopushinsky, W.

    During the spring and summer of 1981, airborne ash previously deposited from the 1980 eruption of Mount St. Helens volcano was monitored at several field locations near the major axis of the depositional pattern in Washington State. Airborne ash was collected daily with standard high-volume samplers and other equipment that sampled the ash at selected windspeeds. Analysis of high-volume filtered deposits showed poor linear correlations to local meteorological conditions. At Moses Lake, weights of windspeed-selected samples indicated an exponential increase in suspended material with increasing windspeed. Wind tunnel tests with ash from two locations varying in distance from the volcano showed that the finer ash fractions from both locations became airborne at similar windspeeds. Threshold wind velocity was about 12 km h -1 for newly deposited ash, compared to more than 69 km h -1 for ash consolidated by wetting and drying.

  3. Overview of meteorological conditions and micrometeorological CO2 fluxes over a Scots pine forest at Sodankyl during SIFLEX-200

    NASA Astrophysics Data System (ADS)

    Laurila, T.; Thum, T.; Aurela, M.; Lohila, A.; Lindfors, V.

    observed on April 23 and the maximum photochemical efficiency Fv/Fm increased from the winter value of 0.1 to above 0.5. The end of April and the beginning of May were much warmer than the average long-term average. In May, night frosts were common and the net CO2 fluxes at noon were around 0.2 mg m-2s-1. The maximum photochemical efficiency Fv/Fm varied between 0.5 and 0.75 depending on air temperature. The last days of May and the beginning of June were warmer than the climatological average. After May 27, night frost was not observed any more, and the noontime CO2 fluxes increased to -0.3 mg m-2s-1 which is a typical summer value. Fv/Fm rose to above 0.8 which representing summer conditions. Seasonal changes of maximum photochemical efficiency of photosystem II of Scots pine needles tracked very well the CO2 uptake potential of a Scots pine forest north of the Arctic Circle.

  4. Detection of turbulent coherent motions in a forest canopy part II: Time-scales and conditional averages

    NASA Astrophysics Data System (ADS)

    Collineau, Serge; Brunet, Yves

    1993-10-01

    Turbulent exchanges between plant canopies and the atmosphere are known to be strongly affected by intermittent coherent motions, which appear on time traces of turbulent variables as periodic, large-amplitude excursions from the mean. Detecting these features requires objective and powerful signal analysis techniques. We investigate here the possibilities offered by the recently developed wavelet transform, presented in a companion paper. For this purpose, a set of data acquired in a 13.5 m high pine forest in southwestern France was used, which provided time series of wind velocities and air temperature recorded at two levels simultaneously, under moderately unstable conditions. Firstly, a duration scale of the active part of coherent motions was estimated from the wavelet variance. Then, we focused on the detection itself of large-scale features; several wavelet functions were tested, and the results compared with those obtained from more classical conditional sampling methods such as VITA and WAG. A mean time interval Δ=1.8 h/u * ( h being the canopy height and u * the friction velocity) between contiguous coherent motions was obtained. The features extracted from the various traces and ensemble-averaged over 30 min periods appeared very similar throughout the four hours of data studied. They provided a dynamic description of the ejection-sweep process, readily observable at both levels. An alternate Reynolds decomposition of the instantaneous turbulent fields, using the conditionally averaged signals, allowed the relative importance of large- and small-scale contributions to momentum and heat fluxes to be estimated. The results were found to be in good agreement with comparable studies.

  5. Geology, hydrology, and water quality of the glacial drift aquifer in the vicinity of the Nelson landfill near Yorkville, Illinois

    USGS Publications Warehouse

    Kay, Robert T.

    2006-01-01

    The geologic and hydrologic characteristics of the sand-and-gravel deposits that compose the glacial drift aquifer in the vicinity of the Nelson Landfill site in Yor-kville, Illinois indicate that the aquifer could be devel-oped as a source of public water supply. The geology of these deposits within the Newark Bedrock Valley is com-plex, however, and a detailed investigation of their water bearing and transmitting properties will be required to successfully locate high-capacity wells. Volatile organic compounds, pesticides, and cyanide were not detected in ground water during this investiga-tion. Metals and nitrogen compounds were not detected at concentrations above their Maximum Contaminant Level. Iron, manganese, and aluminum were detected at concentrations above their Secondary Maximum Con-taminant Level and various constituents were detected at concentrations above background levels downgradi-ent of the landfill. Nitrate and ammonia, presumably derived from agricultural practices, also were detected in samples from locations hydraulically upgradient of the landfill. Oxidation-reduction conditions in the aquifer become more reducing with depth. This change is reflected by a change in the type of nitrogen compound detected and the concentration of dissolved oxygen and iron in the glacial drift aquifer. Concentrations of some of the major ions and metals may be affected by disso-lution of carbonate minerals in the aquifer and perhaps road salts.

  6. Remote sensing of interannual boreal forest NDVI in relation to climatic conditions in interior Alaska

    NASA Astrophysics Data System (ADS)

    Verbyla, David

    2015-12-01

    Climate has warmed substantially in interior Alaska and several remote sensing studies have documented a decadal-scale decline in the normalized difference vegetation index (NDVI) termed a ‘browning trend’. Reduced summer soil moisture due to changing climatic factors such as earlier springs, less snowpack, and summer drought may reduce boreal productivity and NDVI. However, the relative importance of these climatic factors is poorly understood in boreal interior Alaska. In this study, I used the remotely sensed peak summer NDVI as an index of boreal productivity at 250 m pixel size from 2000 to 2014. Maximum summer NDVI was related to last day of spring snow, early spring snow water equivalent (SWE), and a summer moisture index. There was no significant correlation between early spring SWE and peak summer NDVI. There was a significant correlation between the last day of spring snow and peak summer NDVI, but only for a few higher elevation stations. This was likely due to snowmelt occurring later at higher elevations, thus having a greater effect on summer soil moisture relative to lower elevation sites. For most of boreal interior Alaska, summer drought was likely the dominant control on peak summer NDVI and this effect may persist for several years. Peak summer NDVI declined at all 26 stations after the 2004 drought, and the decline persisted for 2 years at all stations. Due to the shallow rooting zone of most boreal plants, even cool and moist sites at lower elevations are likely vulnerable to drought. For example the peak summer NDVI response following the 2004 drought was similar for adjacent cold and warm watershed basins. Thus, if frequent and severe summer droughts continue, moisture stress effects are likely to be widespread and prolonged throughout most of interior boreal Alaska, including relatively cool, moist sites regardless of spring snowpack conditions or spring phenology.

  7. The divine clockwork: Bohr's correspondence principle and Nelson's stochastic mechanics for the atomic elliptic state

    SciTech Connect

    Durran, Richard; Neate, Andrew; Truman, Aubrey

    2008-03-15

    We consider the Bohr correspondence limit of the Schroedinger wave function for an atomic elliptic state. We analyze this limit in the context of Nelson's stochastic mechanics, exposing an underlying deterministic dynamical system in which trajectories converge to Keplerian motion on an ellipse. This solves the long standing problem of obtaining Kepler's laws of planetary motion in a quantum mechanical setting. In this quantum mechanical setting, local mild instabilities occur in the Keplerian orbit for eccentricities greater than (1/{radical}(2)) which do not occur classically.

  8. [A biographical profile of Nelson Chaves and his contribution to nutrition in public health in Brazil].

    PubMed

    de Assis Guedes de Vasconcelos, F

    2001-01-01

    This study focuses on the academic and intellectual career of scientist Nelson Chaves, founder of the Nutritionists School and the Institute of Nutrition at the Federal University in Pernambuco. The methodology was based on quantitative and qualitative analyses of this author's scientific production, published from 1932 to 1982. Beginning with his search for solutions to malnutrition children from the Zona da Mata region in Pernambuco, this scientist created what is commonly called the humanist-ecological paradigm of the Brazilian nutritional issue, thus contributing to the institutionalization of the field of nutrition in public health throughout Brazil.

  9. The Westphalian D fossil lepidodendrid forest at Table Head, Sydney Basin, Nova Scotia: Sedimentology, paleoecology and floral response to changing edaphic conditions

    USGS Publications Warehouse

    Calder, J.H.; Gibling, M.R.; Eble, C.F.; Scott, A.C.; MacNeil, D.J.

    1996-01-01

    Strata of Westphalian D age on the western coast of the Sydney Basin expose a fossil forest of approximately 30 lepidodendrid trees within one of several clastic splits of the Harbour Seam. A mutidisciplinary approach was employed to interpret the origins of the coal bed, the depositional history of the site and the response of the fossil forest to changing edaphic conditions. The megaspore and miospore records indicate that the mire vegetation was dominated by arboreous lycopsids, especially Paralycopodites, with subdominant tree ferns. Petrographic, palynological and geochemical evidence suggest that the Harbour coal bed at Table Head originated as a rheotrophic (cf. planar) mire (eutric histosol). The mire forest is interpreted to have been engulfed by prograding distributary-channel sediments; sparse protist assemblages are suggestive of a freshwater delta-plain lake environment occasionally in contact with brackish waters. Lepidodendrids persisted as site colonizers of clastic substrates even after burial of the rheotrophic peatland and influenced the morphology of deposited sediment, but apparently were unable to colonize distributary channels. Equivocal taxonomic data (compression fossils) show the fossil forest to have been composed of both monocarpic (Lepidodendron) and polycarpic (Diaphorodendron, Paralycopodites, ?Sigillaria) lycopsids, genera recorded in the palynology of the uppermost ply of the underlying coal bed. Comparatively rare within the clastic beds of the fossil forest, however, is the stem compression of Paralycopodites, whose dispersed megapores and miospores dominate the underlying coal bed. Tree diameter data recorded equivalent to breast height indicate a forest of mixed age. These data would appear to suggest that some lepidodendrids employing a polycarpic reproductive strategy were better able to cross the ecological barrier imposed between peat and clastic substrates. Foliar compressions indicate that an understory or stand of

  10. Influence of Vegetation Structure on Lidar-derived Canopy Height and Fractional Cover in Forested Riparian Buffers During Leaf-Off and Leaf-On Conditions

    PubMed Central

    Wasser, Leah; Day, Rick; Chasmer, Laura; Taylor, Alan

    2013-01-01

    Estimates of canopy height (H) and fractional canopy cover (FC) derived from lidar data collected during leaf-on and leaf-off conditions are compared with field measurements from 80 forested riparian buffer plots. The purpose is to determine if existing lidar data flown in leaf-off conditions for applications such as terrain mapping can effectively estimate forested riparian buffer H and FC within a range of riparian vegetation types. Results illustrate that: 1) leaf-off and leaf-on lidar percentile estimates are similar to measured heights in all plots except those dominated by deciduous compound-leaved trees where lidar underestimates H during leaf off periods; 2) canopy height models (CHMs) underestimate H by a larger margin compared to percentile methods and are influenced by vegetation type (conifer needle, deciduous simple leaf or deciduous compound leaf) and canopy height variability, 3) lidar estimates of FC are within 10% of plot measurements during leaf-on periods, but are underestimated during leaf-off periods except in mixed and conifer plots; and 4) depth of laser pulse penetration lower in the canopy is more variable compared to top of the canopy penetration which may influence within canopy vegetation structure estimates. This study demonstrates that leaf-off lidar data can be used to estimate forested riparian buffer canopy height within diverse vegetation conditions and fractional canopy cover within mixed and conifer forests when leaf-on lidar data are not available. PMID:23382966

  11. Influence of vegetation structure on lidar-derived canopy height and fractional cover in forested riparian buffers during leaf-off and leaf-on conditions.

    PubMed

    Wasser, Leah; Day, Rick; Chasmer, Laura; Taylor, Alan

    2013-01-01

    Estimates of canopy height (H) and fractional canopy cover (FC) derived from lidar data collected during leaf-on and leaf-off conditions are compared with field measurements from 80 forested riparian buffer plots. The purpose is to determine if existing lidar data flown in leaf-off conditions for applications such as terrain mapping can effectively estimate forested riparian buffer H and FC within a range of riparian vegetation types. Results illustrate that: 1) leaf-off and leaf-on lidar percentile estimates are similar to measured heights in all plots except those dominated by deciduous compound-leaved trees where lidar underestimates H during leaf off periods; 2) canopy height models (CHMs) underestimate H by a larger margin compared to percentile methods and are influenced by vegetation type (conifer needle, deciduous simple leaf or deciduous compound leaf) and canopy height variability, 3) lidar estimates of FC are within 10% of plot measurements during leaf-on periods, but are underestimated during leaf-off periods except in mixed and conifer plots; and 4) depth of laser pulse penetration lower in the canopy is more variable compared to top of the canopy penetration which may influence within canopy vegetation structure estimates. This study demonstrates that leaf-off lidar data can be used to estimate forested riparian buffer canopy height within diverse vegetation conditions and fractional canopy cover within mixed and conifer forests when leaf-on lidar data are not available.

  12. Using conditional tree forests and life history traits to assess specific risks of stream degradation under multiple pressure scenario.

    PubMed

    Mondy, Cédric P; Usseglio-Polatera, Philippe

    2013-09-01

    The full accomplishment of the European Water Framework Directive objectives has required from EU members three successive steps: (i) the evaluation of their water body ecological status, (ii) the risk assessment of different anthropogenic pressure categories and (iii) the implementation of appropriate management and restoration programs. We aimed at designing an innovative retrospective ecological risk assessment (ERA) tool working for most of the French wadeable rivers in a context of multiple anthropogenic pressures (step ii). This tool, including conditional tree forest (CTF) models, was built on combinations of benthic macroinvertebrate trait-based metrics for each of sixteen anthropogenic pressure categories. For eleven pressure categories, CTF models have given good impairment risk assessment (i.e. AUC≥0.70), even at moderate risk level and in a multi-pressure context. The four other models have provided poorer but promising results (AUC=0.67±0.02). Identifying the potential weight of individual anthropogenic pressures that lead to biotic assemblage impairment in streams under multiple pressure scenario, is a key step for managers to implement appropriate stream restoration programs. Simultaneously considering the whole complexity of bio-ecological adaptations within biotic assemblages subjected to human pressures provides a functional diagnostic tool both (i) ecologically relevant and (ii) efficient for ERA.

  13. Use of the Priestley-Taylor evaporation equation for soil water limited conditions in a small forest clearcut

    USGS Publications Warehouse

    Flint, A.L.; Childs, S.W.

    1991-01-01

    The Priestley-Taylor equation, a simplification of the Penman equation, was used to allow calculations of evapotranspiration under conditions where soil water supply limits evapotranspiration. The Priestley-Taylor coefficient, ??, was calculated to incorporate an exponential decrease in evapotranspiration as soil water content decreases. The method is appropriate for use when detailed meteorological measurements are not available. The data required to determine the parameter for the ?? coefficient are net radiation, soil heat flux, average air temperature, and soil water content. These values can be obtained from measurements or models. The dataset used in this report pertains to a partially vegetated clearcut forest site in southwest Oregon with soil depths ranging from 0.48 to 0.70 m and weathered bedrock below that. Evapotranspiration was estimated using the Bowen ratio method, and the calculated Priestley-Taylor coefficient was fitted to these estimates by nonlinear regression. The calculated Priestley-Taylor coefficient (?????) was found to be approximately 0.9 when the soil was near field capacity (0.225 cm3 cm-3). It was not until soil water content was less than 0.14 cm3 cm-3 that soil water supply limited evapotranspiration. The soil reached a final residual water content near 0.05 cm3 cm-3 at the end of the growing season. ?? 1991.

  14. Montana's forest resources. Forest Service resource bulletin

    SciTech Connect

    Conner, R.C.; O'Brien, R.A.

    1993-09-01

    The report includes highlights of the forest resource in Montana as of 1989. Also the study describes the extent, condition, and location of the State's forests with particular emphasis on timberland. Includes statistical tables, area by land classes, ownership, and forest type, growing stock and sawtimber volumes, growth, mortality, and removals for timberland.

  15. Effects of forest fragmentation on the winter body condition and population parameters of an habitat generalist, the wood mouse Apodemus sylvaticus: a test of hypotheses

    NASA Astrophysics Data System (ADS)

    Díaz, Mario; Santos, Tomás; Tellería, JoséLuis

    1999-02-01

    Three main causal hypotheses have been proposed to explain the inverse relationships between habitat patch size and density of generalist mouse species in fragmented habitats: 1) enhanced habitat conditions as habitat patch size decreases; 2) inhibited emigration of excess individuals in small and isolated habitat patches; and 3) reduced territoriality in small patches because they are occupied temporarily by nonreproductive individuals. From the mechanism underlying each hypothesis, we derived predictions on the effects of fragment size on the body condition of individuals (measured both as absolute body size and as body mass relative to body size) and some demographic parameters of mouse populations related to reproductive output (sex-ratio and proportions of sexually active and recently-born individuals), and we tested such predictions with data from wood mice Apodemus sylvaticus wintering in three Spanish forest archipelagos in which the inverse relationship between forest patch size and mouse abundance had been previously proven. No differences in average body size or in average body mass relative to body size were detected among fragments. Mouse populations wintering in small fragments showed more male-biased sex-ratios, a larger proportion of sexually active adults and fewer juveniles as compared to mouse populations wintering in large fragments nearby. Results clearly rejected the third hypothesis and did not support the second one. It thus seemed that habitat conditions for mice improved as forest fragment size decreased, although the expected positive effects on individuals could have been prevented by relaxed territoriality and increased food resource depletion by denser mouse populations. Bearing in mind the negative effects of dense wood mice populations on the distribution, abundance and population dynamics of forest species, this apparent enhancement of habitat conditions for mice in small forest fragments could have far-reaching consequences for the

  16. Co-effect of increased humidity and meteorological conditions on greenhouse gas fluxes in a young hybrid aspen forest

    NASA Astrophysics Data System (ADS)

    Hansen, Raili; Mander, Ülo; Kupper, Priit; Soosaar, Kaido; Maddison, Martin; Sõber, Jaak; Lõhmus, Krista

    2014-05-01

    Due to the climate change, higher precipitation and an increase in air humidity is expected in northern Europe in the near future (IPCC 2007). There are some studies about irrigation, elevated CO2 and O3 etc., but still we have too little knowledge about the humidity effect on the deciduous forest ecosystem. In 2006 a free-air humidity manipulation (FAHM) facility was established in Estonia and in 2008 we started to artificially increase the air humidity in young hybrid aspen (Populus tremula L. x P. tremuloides Michx.) forest trials on an Endogleyic Planosol of former arable land. Air humidity was raised on average about 7% compared to ambient condition (Tullus et al., 2012). We measured the carbon dioxide, methane and nitrous oxide fluxes from the FAHM system using closed static chamber and gas-chromatograph techniques from July 2009 to November 2012 during snow free periods. Flux measurements were done once a month in three humidification (h) plots and in three control (c) plots. We monitored soil temperature, soil water potential (SWP), precipitation and relative humidity. The vegetation period was rainy in 2009, droughty in 2010 and 2011 (according to SWP the drought was severe in 2011) and cold in 2012. Soil respiration was the lowest in 2011 both in c and h plots; however it was significantly higher in h. Most of the time the soil was a sink for methane, but less CH4 was oxidized in the soil of h plots. Emission of N2O did not have good correlation with air humidity, although one could observe a clear tendency of bigger N2O fluxes when soil was continuously water-saturated. Expectedly, soil respiration had strong positive correlations with soil temperature and CH4 emission demonstrated strong positive correlation with SWP. Hence, interaction of humidification and precipitation affected greenhouse gas fluxes. IPCC, Climate Change 2007: The Physical Science Basis. Cambridge University Press, Cambridge. 2007. Tullus A, Kupper P, Sellin A, Parts L, Sõber J

  17. Public health assessment for U.S. Titanium, Piney River, Nelson County, Virginia, Region 3. CERCLIS number VAD980705404; Final report

    SciTech Connect

    1999-03-01

    The US Titanium site, a former titanium dioxide manufacturing plant, is located in Nelson County, Virginia, along the northern side of the Piney River. As a result of buried coppers as currently on-site, soils, ground water, and surface water have exhibited highly acidic conditions and naturally-occurring heavy metals have leached into the ground water. Potential human exposure pathways of concern include ingestion and dermal contact with contaminated surface water; ingestion, dermal contact, and inhalation of contaminated soil and dusts; and ingestion of contaminated fish. VDH has concluded that the U.S. Titanium site poses an indeterminate public health hazard at this time, since data are not available for all environmental media that humans may be exposed to and there are insufficient health outcome data to indicate that the site has had an adverse effect on human health.

  18. Seasonal soil VOC exchange rates in a Mediterranean holm oak forest and their responses to drought conditions

    NASA Astrophysics Data System (ADS)

    Asensio, Dolores; Peñuelas, Josep; Ogaya, Romà; Llusià, Joan

    Available information on soil volatile organic compound (VOC) exchange, emissions and uptake, is very scarce. We here describe the amounts and seasonality of soil VOC exchange during a year in a natural Mediterranean holm oak forest growing in Southern Catalonia. We investigated changes in soil VOC dynamics in drought conditions by decreasing the soil moisture to 30% of ambient conditions by artificially excluding rainfall and water runoff, and predicted the response of VOC exchange to the drought forecasted in the Mediterranean region for the next decades by GCM and ecophysiological models. The annual average of the total (detected) soil VOC and total monoterpene exchange rates were 3.2±3.2 and -0.4±0.3 μg m -2 h -1, respectively, in control plots. These values represent 0.003% of the total C emitted by soil at the study site as CO 2 whereas the annual mean of soil monoterpene exchange represents 0.0004% of total C. Total soil VOC exchange rates in control plots showed seasonal variations following changes in soil moisture and phenology. Maximum values were found in spring (17±8 μg m -2 h -1). Although there was no significant global effect of drought treatment on the total soil VOC exchange rates, annual average of total VOC exchange rates in drought plots resulted in an uptake rate (-0.5±1.8 μg m -2 h -1) instead of positive net emission rates. Larger soil VOC and monoterpene exchanges were measured in drought plots than in control plots in summer, which might be mostly attributable to autotrophic (roots) metabolism. The results show that the diversity and magnitude of monoterpene and VOC soil emissions are low compared with plant emissions, that they are driven by soil moisture, that they represent a very small part of the soil-released carbon and that they may be strongly reduced or even reversed into net uptakes by the predicted decreases of soil water availability in the next decades. In all cases, it seems that VOC fluxes in soil might have greater

  19. Relative Importance of Current and Past Landscape Structure and Local Habitat Conditions for Plant Species Richness in Dry Grassland-Like Forest Openings

    PubMed Central

    Husáková, Iveta; Münzbergová, Zuzana

    2014-01-01

    In fragmented landscapes, plant species richness may depend not only on local habitat conditions but also on landscape structure. In addition, both present and past landscape structure may be important for species richness. There are, however, only a few studies that have investigated the relative importance of all of these factors. The aim of this study was to examine the effect of current and past landscape structures and habitat conditions on species richness at dry grassland-like forest openings in a forested landscape and to assess their relative importance for species richness. We analyzed information on past and present landscape structures using aerial photographs from 1938, 1973, 1988, 2000 and 2007. We calculated the area of each locality and its isolation in the present and in the past and the continuity of localities in GIS. At each locality, we recorded all vascular plant species (296 species in 110 forest openings) and information on abiotic conditions of the localities. We found that the current species richness of the forest openings was significantly determined by local habitat conditions as well as by landscape structure in the present and in the past. The highest species richness was observed on larger and more heterogeneous localities with rocks and shallow soils, which were already large and well connected to other localities in 1938. The changes in the landscape structure in the past can thus have strong effects on current species richness. Future studies attempting to understand determinants of species diversity in fragmented landscapes should also include data on past landscape structure, as it may in fact be more important than the present structure. PMID:24809474

  20. Relative importance of current and past landscape structure and local habitat conditions for plant species richness in dry grassland-like forest openings.

    PubMed

    Husáková, Iveta; Münzbergová, Zuzana

    2014-01-01

    In fragmented landscapes, plant species richness may depend not only on local habitat conditions but also on landscape structure. In addition, both present and past landscape structure may be important for species richness. There are, however, only a few studies that have investigated the relative importance of all of these factors. The aim of this study was to examine the effect of current and past landscape structures and habitat conditions on species richness at dry grassland-like forest openings in a forested landscape and to assess their relative importance for species richness. We analyzed information on past and present landscape structures using aerial photographs from 1938, 1973, 1988, 2000 and 2007. We calculated the area of each locality and its isolation in the present and in the past and the continuity of localities in GIS. At each locality, we recorded all vascular plant species (296 species in 110 forest openings) and information on abiotic conditions of the localities. We found that the current species richness of the forest openings was significantly determined by local habitat conditions as well as by landscape structure in the present and in the past. The highest species richness was observed on larger and more heterogeneous localities with rocks and shallow soils, which were already large and well connected to other localities in 1938. The changes in the landscape structure in the past can thus have strong effects on current species richness. Future studies attempting to understand determinants of species diversity in fragmented landscapes should also include data on past landscape structure, as it may in fact be more important than the present structure.

  1. Hyperspectral data for assessment of temporal changes in Norway spruce forest conditions in the mountainous region of the Czech Republic affected by long-term acidic deposition

    NASA Astrophysics Data System (ADS)

    Albrechtova, J.; Lhotakova, Z.; Misurec, J.; Kopackova, V.; Campbell, P. K. E.; Edwards-Jonasova, M.; Kupkova, L.; Cervena, L.; Potuckova, M.; Cudlin, P.

    2015-12-01

    The Ore Mts. located in the western part of the Czech Republic suffered during 1950's-1990´s heavy atmospheric pollution due to the mining activities and brown coal combustion. Acidic deposition in combination with harsh climatic conditions led there to large-scale forest decline. Although the load of SO2 has significantly decreased since 1991, tree damage was still visible in 1998 in terms of high defoliation or dead trees. Nowadays Norway spruce trees do not exhibit visible symptoms of damage but the full recovery of Norway spruce forests is not complete yet due to persisting adverse soil conditions. The temporal changes in the physiological status of Norway spruce forests in the Krušné Hory Mts. were evaluated using two sets of spectral images acquired in 1998 (ASAS) and in 2013 (APEX) and ground truth data (LAI, tree crown status, photosynthetic pigment contents, leaf spectral properties measured by spectroradiometer, soil properties - pH, contents of basic cations, heavy metals, etc.). Ground truth data were evaluated by unconstrained and constrained multivariate analyses using Canoco 5. The high resolution spectral images (ASAS and APEX) enabled the identification of a gradient of forest conditions and their comparison. In 1998 the stands exhibited different physiological status corresponding to the pollution gradient with healthier trees at the western part of the mountains. Analysis of the foliar chemistry in 2013 show a slight improvement of the Norway spruce physiological status in the eastern part of the mountains while the status of the western-located stands slightly worsened. In 2013 we also studied the differences in soil geochemical conditions, which appeared to be less favorable in the western part of the mountains characterized by a low base cation contents in the top organic horizon and a very low pH (pH<3).

  2. Determination of critical habitat for the endangered Nelson's bighorn sheep in southern California

    USGS Publications Warehouse

    Turner, J.C.; Douglas, C.L.; Hallum, C.R.; Krausman, P.R.; Ramey, R.R.

    2004-01-01

    The United States Fish and Wildlife Service's (USFWS) designation of critical habitat for the endangered Nelson's bighorn sheep (Ovis canadensis nelsoni) in the Peninsular Ranges of southern California has been controversial because of an absence of a quantitative, repeatable scientific approach to the designation of critical habitat. We used 12,411 locations of Nelson's bighorn sheep collected from 1984-1998 to evaluate habitat use within 398 km2 of the USFWS-designated critical habitat in the northern Santa Rosa Mountains, Riverside County, California. We developed a multiple logistic regression model to evaluate and predict the probability of bighorn use versus non-use of native landscapes. Habitat predictor variables included elevation, slope, ruggedness, slope aspect, proximity to water, and distance from minimum expanses of escape habitat. We used Earth Resources Data Analysis System Geographic Information System (ERDAS-GIS) software to view, retrieve, and format predictor values for input to the Statistical Analysis Systems (SAS) software. To adequately account for habitat landscape diversity, we carried out an unsupervised classification at the outset of data inquiry using a maximum-likelihood clustering scheme implemented in ERDAS. We used the strata resulting from the unsupervised classification in a stratified random sampling scheme to minimize data loads required for model development. Based on 5 predictor variables, the habitat model correctly classified >96% of observed bighorn sheep locations. Proximity to perennial water was the best predictor variable. Ninety-seven percent of the observations were within 3 km of perennial water. Exercising the model over the northern Santa Rosa Mountain study area provided probabilities of bighorn use at a 30 x 30-m2 pixel level. Within the 398 km 2 of USFWS-designated critical habitat, only 34% had a graded probability of bighorn use to non-use ranging from ???1:1 to 6,044:1. The remaining 66% of the study area

  3. The "Naked Truth" Isn't Very Revealing: A Response to Wade Nelson on School Reform in Minnesota.

    ERIC Educational Resources Information Center

    Pitton, Debra Eckerman

    1999-01-01

    A participant in Minnesota's standards-based reform initiative claims Wade Nelson, in his May 1998 "Kappan" article, is misinformed about teachers' exclusion from this movement. The standards constitute a minimal competence level in reading, math, and writing, were developed cooperatively, and have raised teacher expectations of students.…

  4. The Nelson-Denny Reading Test as a Predictor of Academic Success in Selected Classes in a Specific Community College.

    ERIC Educational Resources Information Center

    Gudan, Sirkka

    A review of the literature indicates that the Nelson-Denny Reading Test (NDRT) may be a viable instrument for screening students and predicting their academic success in particular circumstances. In 1981, a study was conducted at Schoolcraft College to determine the extent of the relationship between the reading abilities of entering students and…

  5. The Results of Six Years of Testing College Students with Form E of the Nelson-Denny Test.

    ERIC Educational Resources Information Center

    Wood, Peter H.; And Others

    A study investigated the results of the use of Form E (Vocabulary and Comprehension subtests) of the Nelson-Denny Reading Test (NDRT) with six successive cohorts of freshmen entering a midwestern state university. The purpose of the study was to determine the relationships existing between NDRT scores and other indicators of academic success such…

  6. Commentary: The Development of Hippocampal-Dependent Memory Functions: Theoretical Comments on Jabès and Nelson Review (2015)

    ERIC Educational Resources Information Center

    Bachevalier, Jocelyne

    2015-01-01

    Studies investigating the development of memory processes and their neural substrates have flourished over the past two decades. The review by Jabès and Nelson (2015) adds an important piece to our understanding of the maturation of different elements and circuits within the hippocampal system and their association with the progressive development…

  7. The Nelson A. Rockefeller Institute of Government: From State to National Focus on Political and Policy Studies.

    ERIC Educational Resources Information Center

    Gais, Thomas; Lawrence, Catherine

    2000-01-01

    Describes the early years, shift toward greater autonomy, and current structure and roles of the Nelson A. Rockefeller Institute of Government, a public policy research institute of State University of New York. Founded to facilitate relationships between the university system and state government, it has emerged as a more autonomous research…

  8. Mixing and photoreactivity of dissolved organic matter in the Nelson/Hayes estuarine system (Hudson Bay, Canada)

    NASA Astrophysics Data System (ADS)

    Guéguen, C.; Mokhtar, M.; Perroud, A.; McCullough, G.; Papakyriakou, T.

    2016-09-01

    This work presents the results of a 4-year study (2009-2012) investigating the mixing and photoreactivity of dissolved organic matter (DOM) in the Nelson/Hayes estuary (Hudson Bay). Dissolved organic carbon (DOC), colored DOM, and humic-like DOM decreased with increasing salinity (r2 = 0.70-0.84). Removal of DOM was noticeable at low to mid salinity range, likely due to degradation and/or adsorption to particles. DOM photobleaching rates (i.e., decrease in DOM signal resulting from exposure to solar radiation) ranged from 0.005 to 0.030 h- 1, corresponding to half-lives of 4.9-9.9 days. Dissolved organic matter from the Nelson and Hayes Rivers was more photoreactive than from the estuary where the photodegradation of terrestrial DOM decreased with increasing salinity. Coincident with the loss of CDOM absorption was an increase in spectral slope S, suggesting a decrease in DOM molecular weight. Marked differences in photoreactivity of protein- and humic-like DOM were observed with highly humidified material being the most photosensitive. Information generated by our study will provide a valuable data set for better understanding the impacts of future hydroelectric development and climate change on DOM biogeochemical dynamics in the Nelson/Hayes estuary and coastal domain. This study will constitute a reference on terrestrial DOM fate prior to building additional generating capacity on the Nelson River.

  9. 78 FR 66353 - EAM Nelson Holdings, LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-05

    ...-referenced proceeding, of EAM Nelson Holdings, LLC's application for market-based rate authority, with an accompanying rate schedule, noting that such application includes a request for blanket authorization, under 18 CFR Part 34, of future issuances of securities and assumptions of liability. Any person desiring...

  10. "Passageless" administration of the Nelson-Denny Reading Comprehension Test: associations with IQ and reading skills.

    PubMed

    Ready, Rebecca E; Chaudhry, Maheen F; Schatz, Kelly C; Strazzullo, Sarah

    2013-01-01

    There are few tests that assess reading comprehension in adults, but these tests are needed for a comprehensive assessment of reading disorders (RD). The Nelson-Denny Reading Test (NDRT) has a long-passage reading comprehension component that can be used with adolescents and adults. A problem with the NDRT is that reading comprehension test items can be answered correctly without reading the associated passage. The current study determined how IQ, verbal comprehension, and reading skills were associated with scores on a passageless administration of the NDRT. Results indicated that IQ, verbal comprehension, and broad reading skills were significantly associated with greater NDRT passageless scores. Results raise questions about the validity of the reading comprehension component of the NDRT and suggest that the test may have differential validity based on individual differences in vocabulary, general fund of knowledge, and broad reading skills.

  11. Application of an improved Nelson-Nguyen analysis to eccentric, arbitrary profile liquid annular seals

    NASA Technical Reports Server (NTRS)

    Padavala, Satyasrinivas; Palazzolo, Alan B.; Vallely, Pat; Ryan, Steve

    1994-01-01

    An improved dynamic analysis for liquid annular seals with arbitrary profile based on a method, first proposed by Nelson and Nguyen, is presented. An improved first order solution that incorporates a continuous interpolation of perturbed quantities in the circumferential direction, is presented. The original method uses an approximation scheme for circumferential gradients, based on Fast Fourier Transforms (FFT). A simpler scheme based on cubic splines is found to be computationally more efficient with better convergence at higher eccentricities. A new approach of computing dynamic coefficients based on external specified load is introduced. This improved analysis is extended to account for arbitrarily varying seal profile in both axial and circumferential directions. An example case of an elliptical seal with varying degrees of axial curvature is analyzed. A case study based on actual operating clearances of an interstage seal of the Space Shuttle Main Engine High Pressure Oxygen Turbopump is presented.

  12. [A life among insects and books: an interview with Nelson Papavero].

    PubMed

    Klassa, Bruna; Santos, Charles Morphy D

    2012-12-01

    Nelson Papavero is one of the top representatives of Brazilian zoology. His decisive contributions to this science began in the second half of the twentieth century, when he started publishing in the areas of zoology, systematics, biogeography, and the history of science while also working at graduate courses and training teachers and students. He was key to the introduction of Hennig's phylogenetic systematics in Brazil and its chief advocate. His active participation in the creation of the Special Courses on Zoological Systematics within the National Council for Scientific and Technological Development and his work at numerous administrative posts which he held during his academic career were vital to the development of zoology and comparative biology in Brazil. His endeavors also reached into other Latin American countries, like Mexico and Argentina.

  13. Nelson's syndrome: complete remission with cabergoline but not with bromocriptine or cyproheptadine treatment.

    PubMed

    Casulari, Luiz Augusto; Naves, Luciana A; Mello, Paulo A; Pereira Neto, Aldo; Papadia, Carla

    2004-01-01

    A woman affected by Cushing's disease underwent bilateral adrenalectomy followed by radiotherapy of the hypothalamic-pituitary area when she was 18 years old. Thereafter, she used hydrocortisone acetate replacement therapy (35.5 mg divided into two daily doses). At the age of 26 years, the patient exhibited the clinical signs of the Nelson's syndrome, i.e. skin and gingival hyperpigmentation accompanied by amenorrhea, and elevated ACTH plasma levels (2,850 pg/ml, normal range 15-80 pg/ml). The magnetic resonance imaging (MRI) analysis of the sellar region evidenced a pituitary macroadenoma, measuring 14 x 13 mm. The patient was initially treated with cyproheptadine hydrochloride (12 mg/day) for 18 months. There was a partial improvement of the symptoms, with a reduction of the ACTH plasma levels to 112 pg/ml, but without any modification of the tumor mass. Due to sleepiness and weight gain, the cyproheptadine treatment was interrupted and substituted by a cabergoline (0.5 mg twice a week) therapy. Soon after cabergoline was applied an improvement of the clinical symptoms and signs was observed such as a regression of the tumor mass and the normalization of the ACTH plasma titers (38 pg/ml). Later, cabergoline was substituted by bromocriptine (7.5 mg/day) and the plasma levels of ACTH increased again (247 pg/ml), and headache and cutaneous hyperpigmentation were recorded. When cabergoline was reintroduced there was a clinical improvement and normalization of ACTH plasma levels (64 pg/ml). The MRI analysis of the sella region demonstrated a complete remission of the pituitary adenoma. The results obtained show for the first time that a long-term treatment with cabergoline also brings about a complete remission of Nelson's syndrome in the presence of a pituitary macroadenoma.

  14. Forested wetlands

    SciTech Connect

    Lugo, A.E.; Brinson, M.; Brown, S.

    1990-01-01

    Forested wetlands have important roles in global biogeochemical cycles, supporting freshwater and saltwater commercial fisheries, and in providing a place for wildlife of all kinds to flourish. Scientific attention towards these ecosystems has lagged with only a few comprehensive works on forested wetlands of the world. A major emphasis of this book is to develop unifying principles and data bases on the structure and function of forested wetlands, in order to stimulate scientific study of them. Wetlands are areas that are inundated or saturated by surface-water or ground-water, at such a frequency and duration that under natural conditions they support organisms adapted to poorly aerated and/or saturated soil. The strategy of classifying the conditions that control the structure and behavior of forested wetlands by assuming that the physiognomy and floristic composition of the system will reflect the total energy expenditure of the ecosystem; and the structural and functional characteristics of forested wetlands from different parts of the world are the major topics covered.

  15. Assessment of the state of soil microbial cenoses in the forest-tundra zone under conditions of airborne industrial pollution

    NASA Astrophysics Data System (ADS)

    Bogorodskaya, A. V.; Ponomareva, T. V.; Shapchenkova, O. A.; Shishikin, A. S.

    2012-05-01

    The quantitative and functional responses of soil microbial cenoses in the forest-tundra zone to pollution have been studied in the area exposed to emissions from the Norilsk Mining and Metallurgical Works. The strongest structural and functional disturbances of the soil biota have been recorded on the plots with completely destroyed vegetation. A decrease in the content of microbial carbon and an elevated respiration rate in the technogenically transformed soils provide evidence for the functioning of the microbial communities under stress caused by the continuous input of aggressive pollutants. The degree of transformation and the contents of technogenic elements (Ni, Cu, Co, Pb, and S) in the organic horizons of the forest-tundra soils are the major factors affecting the development and functioning of the soil microbial cenoses.

  16. Influence of small scale conditions on the diversity of wood decay fungi in a temperate, mixed deciduous forest canopy.

    PubMed

    Unterseher, Martin; Tal, Ophir

    2006-02-01

    Studies on fungal richness and ecology have been largely disregarded since the first intensive efforts to investigate organismal diversity in forest canopies. We used the Leipzig Canopy Crane research facility to sample wood-decaying fungi in a mixed deciduous forest canopy 10-30 m in height. The structural complexity of the canopy was analysed using different methods, including meteorological measurements. With respect to temperature and relative humidity, marked differences existed between forest floor and upper canopy layers that persisted on smaller scales. Of the 118 taxa found in 128 sample units, pyrenomycetes and corticioid fungi outnumbered other macrofungal groups. Fungal communities showed distinct variations both in species richness and composition with respect to substrate (tree species), height in the canopy, stage of decay, and branch diameter. Pyrenomycetes and their anamorphs dominated the mycobiota on thin, exposed twigs at great heights, indicating their ability to overcome extended periods of drought and high levels of solar irradiance. Other taxa of Tremellales (Exidia spp.), Orbiliales (Hyalorbilia inflatula, Orbilia spp.) or Agaricales (Episphaeria fraxinicola, Cyphellopsis anomala, Lachnella spp.) also exhibited features that enabled them to develop in lesser protected habitats within tree crowns.

  17. [Seedlings growth and survival of five Acacia (Fabaceae) species that coexists in neotropical semi-arid forests of Argentina, under different light and water availability conditions].

    PubMed

    Venier, Paula; Cabido, Marcelo; Mangeaud, Arnaldo; Funes, Guillermo

    2013-06-01

    Seedlings growth and survival of five Acacia (Fabaceae) species that coexists in neotropical semi-arid forests of Argentina, under different light and water availability conditions. Seedling establishment is one of the most risky stages of plants, especially in arid and semiarid regions, where low water availability and high solar radiation influence its emergence, development and survival. In seasonally dry xerophytic forests occurring in North-Western Córdoba, central Argentina, five neotropical species of Acacia co-exist: A. aroma, A. caven, A. atramentaria, A. gilliesii and A. praecox. With the aim to evaluate growth variables and survival of these five species seedlings, in response to water stress and different light availability conditions, a greenhouse experiment was undertaken from March to June of 2010. Although small differences were found between species (F = 5.66, p = 0.001), all of them showed high percentages of seedling survival in response to different light and water treatments, suggesting that seedlings would be tolerant to water stress and could be established both in light and shade. On the other hand, although all species showed an increase in growth in light conditions and without water stress, we have found some trends towards a greater growth in the seedlings ofA. aroma, A. caven and A. atramentaria when compared to those of A. praecox and A. gilliessi in most of the variables considered (F = 41.9, p < 0.0001; F = 7.06, p < 0.0001; F = 53.59, p < 0.0001). This pattern was confirmed through a cluster analysis that classified the species in two main groups. These results, together with others already reported, would indicate a regenerative niche differentiation that might be favoring the regional coexistence of these five species in semiarid forests in central Argentina.

  18. Nelson's syndrome: single centre experience using the linear accelerator (LINAC) for stereotactic radiosurgery and fractionated stereotactic radiotherapy.

    PubMed

    Wilson, Peter J; Williams, Janet R; Smee, Robert I

    2014-09-01

    Nelson's syndrome is a unique clinical phenomenon of growth of a pituitary adenoma following bilateral adrenalectomies for the control of Cushing's disease. Primary management is surgical, with limited effective medical therapies available. We report our own institution's series of this pathology managed with radiation: prior to 1990, 12 patients were managed with conventional radiotherapy, and between 1990 and 2007, five patients underwent stereotactic radiosurgery (SRS) and two patients fractionated stereotactic radiotherapy (FSRT), both using the linear accelerator (LINAC). Tumour control was equivocal, with two of the five SRS patients having a reduction in tumour volume, one patient remaining unchanged, and two patients having an increase in volume. In the FSRT group, one patient had a decrease in tumour volume whilst the other had an increase in volume. Treatment related morbidity was low. Nelson's syndrome is a challenging clinical scenario, with a highly variable response to radiation in our series.

  19. Controls of Net Ecosystem Exchange at an Old Field, a Pine Plantation, and a Hardwood Forest under Identical Climatic and Edaphic Conditions-Isotopic Studies

    SciTech Connect

    Chanton, J. P.; Mortazavi, B.

    2004-11-04

    During the past year we have submitted two manuscripts. 1. Mortazavi, B., J. Chanton, J.L. Prater, A.C. Oishi, R. Oren and G. Katul. Temporal variability in 13C of respired CO2 in a pine and a hardwood forest subject to similar climatic conditions (in Press). Oecologia 2. Mortazavi, B. and J. P. Chanton. Use of Keeling plots for determining sources of dissolved organic carbon in nearshore and open ocean systems (Published in Limnology and Oceanography (2004) Vol 49 pages 102-108). 3. Mortazavi, B., J. L. Prater, and J. P. Chanton (2004). A field-based method for simultaneous measurements of the 18O and 13C of soil CO2 efflux. Biogeosciences Vol 1:1-16 Most recent products delivered: Mortazavi, B. and J. P. Chanton. Abiotic and biotic controls on the 13C of respired CO2 in the southeastern US forest mosaics and a new technique for measuring the of soil CO2 efflux. Joint Biosphere Stable Isotope Network (US) and Stable Isotopes in Biosphere Atmosphere Exchange (EU) 2004 Meeting, Interlaken, Switzerland, March 31-April 4, 2004. Mortazavi, B., J. Chanton, J.L. Prater, A.C. Oishi, R. Oren and G. Katul. Temporal variability in 13C of respired CO2 in a pine and a hardwood forest subject to similar climatic conditions. American Geophysical Union Fall Meeting, San Francisco, USA, December 8-12, 2003. Prater, J., Mortazavi, B. and J. P. Chanton. Measurement of discrimination against 13C during photosynthesis and quantification of the short-term variability of 13C over a diurnal cycle. American Geophysical Union Fall Meeting, San Francisco, USA, December 8-12, 2003.

  20. Responses of CO(2), N(2)O and CH(4) fluxes between atmosphere and forest soil to changes in multiple environmental conditions.

    PubMed

    Yan, Junhua; Zhang, Wei; Wang, Keya; Qin, Fen; Wang, Wantong; Dai, Huitang; Li, Peixue

    2014-01-01

    To investigate the effects of multiple environmental conditions on greenhouse gas (CO2 , N2 O, CH4 ) fluxes, we transferred three soil monoliths from Masson pine forest (PF) or coniferous and broadleaved mixed forest (MF) at Jigongshan to corresponding forest type at Dinghushan. Greenhouse gas fluxes at the in situ (Jigongshan), transported and ambient (Dinghushan) soil monoliths were measured using static chambers. When the transported soil monoliths experienced the external environmental factors (temperature, precipitation and nitrogen deposition) at Dinghushan, its annual soil CO2 emissions were 54% in PF and 60% in MF higher than those from the respective in situ treatment. Annual soil N2 O emissions were 45% in PF and 44% in MF higher than those from the respective in situ treatment. There were no significant differences in annual soil CO2 or N2 O emissions between the transported and ambient treatments. However, annual CH4 uptake by the transported soil monoliths in PF or MF was not significantly different from that at the respective in situ treatment, and was significantly lower than that at the respective ambient treatment. Therefore, external environmental factors were the major drivers of soil CO2 and N2 O emissions, while soil was the dominant controller of soil CH4 uptake. We further tested the results by developing simple empirical models using the observed fluxes of CO2 and N2 O from the in situ treatment and found that the empirical models can explain about 90% for CO2 and 40% for N2 O of the observed variations at the transported treatment. Results from this study suggest that the different responses of soil CO2 , N2 O, CH4 fluxes to changes in multiple environmental conditions need to be considered in global change study. PMID:23868392

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

    PubMed

    Schaub, M; Skelly, J M; Zhang, J W; Ferdinand, J A; Savage, J E; Stevenson, R E; Davis, D D; Steiner, K C

    2005-02-01

    The crowns of five canopy dominant black cherry (Prunus serotina Ehrh.), five white ash (Fraxinus americana L.), and six red maple (Acer rubrum L.) trees on naturally differing environmental conditions were accessed with scaffold towers within a mixed hardwood forest stand in central Pennsylvania. Ambient ozone concentrations, meteorological parameters, leaf gas exchange and leaf water potential were measured at the sites during the growing seasons of 1998 and 1999. Visible ozone-induced foliar injury was assessed on leaves within the upper and lower crown branches of each tree. Ambient ozone exposures were sufficient to induce typical symptoms on cherry (0-5% total affected leaf area, LAA), whereas foliar injury was not observed on ash or maple. There was a positive correlation between increasing cumulative ozone uptake (U) and increasing percent of LAA for cherry grown under drier site conditions. The lower crown leaves of cherry showed more severe foliar injury than the upper crown leaves. No significant differences in predawn leaf water potential (psi(L)) were detected for all three species indicating no differing soil moisture conditions across the sites. Significant variation in stomatal conductance for water vapor (g(wv)) was found among species, soil moisture, time of day and sample date. When comparing cumulative ozone uptake and decreased photosynthetic activity (P(n)), red maple was the only species to show higher gas exchange under mesic vs. drier soil conditions (P < 0.05). The inconsistent differences in gas exchange response within the same crowns of ash and the uncoupling relationship between g(wv) and P(n) demonstrate the strong influence of heterogeneous environmental conditions within forest canopies. PMID:15519730

  2. A personal experience in the presence of a man who transformed a nation and changed the world: Nelson Mandela.

    PubMed

    Brown, Geraldine

    2014-01-01

    At this time in history, I consider myself very privileged to have spent some three hours in the presence of President Nelson Mandela as a Howard University faculty member in the late 1990s. Then, President of Howard University, H. Patrick Swygert bestowed upon President Nelson Mandela, Esquire an Honorary Doctorate of Human Letters. I can only equate this experience to my four mile walk up the Bedaling Wall (Great Wall) in China (a magnificent ancient wonder of the world), and trying to relate this event to something only fortunate souls have had the chance to enjoy. I also treasure the once in a lifetime visit to the Republic of South Africa in 1998 when the Association of Black Nursing Faculty, Inc., Chi Eta Phi Nursing Sorority, Inc., and the Department of Nursing (University of Botswana) sponsored the trip as an attempt to establish partnerships, share common interests and discussion in how to meet health needs of emerging majority and disadvantaged populations in the world, including mainly, the continent of Africa, in the 21st century. This short memoir can only piggy-back the massive coverage in the media that began almost instantly as a long anticipated event (death of Nelson Mandela), but startled upon its occurrence. PMID:24660317

  3. Monitoring of the CO2 emission and the contents of microbial biomass in agroecosystems on gray forest soils of the Cisbaikal region under conditions of fluoride pollution

    NASA Astrophysics Data System (ADS)

    Pomazkina, L. V.

    2015-08-01

    The influence of the technogenic pollution of gray forest soils in the forest-steppe zone of the Cisbaikal region with fluorides emitted by aluminum smelters on the functioning and state of local agroecosystems was studied within the framework of a long-term agroecological monitoring program. Hydrothermic conditions of the growing season during the monitoring period (1997-2012) were compared with the climatic norm (1961-1990). It was found that the adverse effect of the technogenic pollution on the agroecosystem becomes more pronounced during the years with abnormal weather conditions. An increase in the CO2 emission into the atmosphere as a response of the microbial complex to the rise in the air temperatures was characterized by the linear dependence irrespectively of the degree of soil contamination. The methods of systems analysis were applied to generalize the results. The considered agroecosystem was studied as the system of particular components (soil-microorganisms-plants-atmosphere) integrated by the carbon fluxes. The regimes of the agroecosystem functioning and the ecological loads on it were estimated on the basis of data on the fluxes of net mineralized and (re)immobilized carbon. The environmental factors affecting the state and functioning of the agroecosystem were identified.

  4. [Changes in the spatial structure of the destruction process under the conditions of atmospheric pollution of forest ecosystems].

    PubMed

    Vorobeĭchik, E L

    2002-01-01

    Contamination of the southern taiga forests (Middle Urals) by discharges from cooper smelters (heavy metals combined with SO2) not only decreases the mean rate of decomposition of pure cellulose, but also radically changes the spatial structure of the destruction process. Heterogeneity of distribution of the destruction rate is sharply increased near the source of discharge due to differentiation of the space into microregions with high and low destruction rates. The characteristic size of spatial heterogeneity amounts to several tens of centimeters and the distribution of microregions with a high rate is accidental within several tens of meters. A hypothesis has been put forward that the described changes in the spatial structure of the destruction process are related, above all, to disturbed colonization of the substrate by soil myxomycetes.

  5. Forested wetland habitat

    USGS Publications Warehouse

    Duberstein, Jamie A.; Krauss, Ken W.; Kennish, Michael J.

    2015-01-01

    A forested wetland (swamp) is a forest where soils are saturated or flooded for at least a portion of the growing season, and vegetation, dominated by trees, is adapted to tolerate flooded conditions. A tidal freshwater forested wetland is a forested wetland that experiences frequent but short-term surface flooding via tidal action, with average salinity of soil porewater less than 0.5 g/l. It is known locally as tidal várzea in the Amazon delta, Brazil. A tidal saltwater forested wetland (mangrove forest) is a forested wetland that experiences frequent but short-term surface flooding via tidal action, with average salinity often exceeding 3 g/l and reaching levels that can exceed seawater. Mangrove ecosystems are composed of facultative halophytes that generally experience better growth at moderate salinity concentrations.

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

    PubMed

    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.

  7. Geologic map of the Nelson quadrangle, Lewis and Clark County, Montana

    USGS Publications Warehouse

    Reynolds, Mitchell W.; Hays, William H.

    2003-01-01

    The geologic map of the Nelson quadrangle, scale 1:24,000, was prepared as part of the Montana Investigations Project to provide new information on the stratigraphy, structure, and geologic history of an area in the geologically complex southern part of the Montana disturbed belt. In the Nelson area, rocks ranging in age from Middle Proterozoic through Cretaceous are exposed on three major thrust plates in which rocks have been telescoped eastward. Rocks within the thrust plates are folded and broken by thrust faults of smaller displacement than the major bounding thrust faults. Middle and Late Tertiary sedimentary and volcaniclastic rocks unconformably overlie the pre-Tertiary rocks. A major normal fault displaces rocks of the western half of the quadrangle down on the west with respect to strata of the eastern part. Alluvial and terrace gravels and local landslide deposits are present in valley bottoms and on canyon walls in the deeply dissected terrain. Different stratigraphic successions are exposed at different structural levels across the quadrangle. In the northeastern part, strata of the Middle Cambrian Flathead Sandstone, Wolsey Shale, and Meagher Limestone, the Middle and Upper Cambrian Pilgrim Formation and Park Shale undivided, the Devonian Maywood, Jefferson, and lower part of the Three Forks Formation, and Lower and Upper Mississippian rocks assigned to the upper part of the Three Forks Formation and the overlying Lodgepole and Mission Canyon Limestones are complexly folded and faulted. These deformed strata are overlain structurally in the east-central part of the quadrangle by a succession of strata including the Middle Proterozoic Greyson Formation and the Paleozoic succession from the Flathead Sandstone upward through the Lodgepole Limestone. In the east-central area, the Flathead Sandstone rests unconformably on the middle part of the Greyson Formation. The north edge, northwest quarter, and south half of the quadrangle are underlain by a

  8. Controls on variations in MODIS fire radiative power in Alaskan boreal forests: implications for fire severity conditions

    USGS Publications Warehouse

    Barrett, Kirsten; Kasischke, Eric S.

    2013-01-01

    Fire activity in the Alaskan boreal forest, though episodic at annual and intra-annual time scales, has experienced an increase over the last several decades. Increases in burned area and fire severity are not only releasing more carbon to the atmosphere, but likely shifting vegetation composition in the region towards greater deciduous dominance and a reduction in coniferous stands. While some recent studies have addressed qualitative differences between large and small fire years in the Alaskan boreal forest, the ecological effects of a greater proportion of burning occurring during large fire years and during late season fires have not yet been examined. Some characteristics of wildfires that can be detected remotely are related to fire severity and can provide new information on spatial and temporal patterns of burning. This analysis focused on boreal wildfire intensity (fire radiative power, or FRP) contained in the Moderate Resolution Imaging Spectroradiometer (MODIS) daily active fire product from 2003 to 2010. We found that differences in FRP resulted from seasonality and intra-annual variability in fire activity levels, vegetation composition, latitudinal variation, and fire spread behavior. Our studies determined two general categories of active fire detections: new detections associated with the spread of the fire front and residual pixels in areas that had already experienced front burning. Residual pixels had a lower average FRP than front pixels, but represented a high percentage of all pixels during periods of high fire activity (large fire years, late season burning, and seasonal periods of high fire activity). As a result, the FRP from periods of high fire activity was less intense than those from periods of low fire activity. Differences related to latitude were greater than expected, with higher latitudes burning later in the season and at a higher intensity than lower latitudes. Differences in vegetation type indicate that coniferous vegetation

  9. Operational validation of a multi-period and multi-criteria model conditioning approach for the prediction of rainfall-runoff processes in small forest catchments

    NASA Astrophysics Data System (ADS)

    Choi, H.; Kim, S.

    2012-12-01

    Most of hydrologic models have generally been used to describe and represent the spatio-temporal variability of hydrological processes in the watershed scale. Though it is an obvious fact that hydrological responses have the time varying nature, optimal values of model parameters were normally considered as time invariants or constants in most cases. The recent paper of Choi and Beven (2007) presents a multi-period and multi-criteria model conditioning approach. The approach is based on the equifinality thesis within the Generalised Likelihood Uncertainty Estimation (GLUE) framework. In their application, the behavioural TOPMODEL parameter sets are determined by several performance measures for global (annual) and short (30-days) periods, clustered using a Fuzzy C-means algorithm, into 15 types representing different hydrological conditions. Their study shows a good performance on the calibration of a rainfall-runoff model in a forest catchment, and also gives strong indications that it is uncommon to find model realizations that were behavioural over all multi-periods and all performance measures, and multi-period model conditioning approach may become new effective tool for predictions of hydrological processes in ungauged catchments. This study is a follow-up study on the Choi and Beven's (2007) model conditioning approach to test how the approach is effective for the prediction of rainfall-runoff responses in ungauged catchments. To achieve this purpose, 6 small forest catchments are selected among the several hydrological experimental catchments operated by Korea Forest Research Institute. In each catchment, long-term hydrological time series data varying from 10 to 30 years were available. The areas of the selected catchments range from 13.6 to 37.8 ha, and all areas are covered by coniferous or broad-leaves forests. The selected catchments locate in the southern coastal area to the northern part of South Korea. The bed rocks are Granite gneiss, Granite or

  10. Forest Management.

    ERIC Educational Resources Information Center

    Weicherding, Patrick J.; And Others

    This bulletin deals with forest management and provides an overview of forestry for the non-professional. The bulletin is divided into six sections: (1) What Is Forestry Management?; (2) How Is the Forest Measured?; (3) What Is Forest Protection?; (4) How Is the Forest Harvested?; (5) What Is Forest Regeneration?; and (6) What Is Forest…

  11. Evaluation of growth potential of Crimean juniper (Juniperus excelsa Bieb.) seedlings for the first growing season under Tekir forest nursery conditions in Kahramanmaras, Turkey.

    PubMed

    Avsar, Mahmut D; Tonguc, Fatih

    2003-04-01

    In this study, growth potential of Crimean juniper (Juniperus excelsa Bieb.) seedlings for the first growing season under Tekir Forest Nursery conditions in Kahramanmaras was evaluated. The height growth of Crimean juniper seedlings was relatively close to that of Lebanon cedar (Cedrus libani A. Rich.) seedlings produced in the same nursery, but their root collar diameters were fairly lower than that of Lebanon cedar seedlings. According to coniferous seedling standards of Turkish Standards Institute, the height growth of Crimean juniper seedlings was fairly good, but their root collar diameters were slightly small. In this respect, that 2+0 or 1+1 Crimean juniper seedlings are used in reforestation activities in the region would be more useful than 1+0 seedlings.

  12. Spatial distributions of forest stand condition, vegetation ground cover, and soil erosion for evaluating the linkages of sediment transport from hillslopes to streams in headwater catchments

    NASA Astrophysics Data System (ADS)

    Gomi, T.; Kumakura, A.; Mizugaki, S.; Takahisa, F.; Ishikawa, Y.; Uchiyama, Y.

    2011-12-01

    We investigated soil erosion and resultant fine sediment transport in headwater catchments with heterogeneous spatial patterns of forest stand condition and vegetation ground cover. The study was conducted in 7 and 5 ha headwater catchments (Watersheds No.3 and No.4, respectively) in Tanzawa mountains area, 60 km of southwest of Tokyo, Japan. We selected 53 points located within catchments including near stream channels to the ridge line. A 0.5 x 0.5 m plot (1m x 1m) were selected in each point for investigating vegetation biomass, litter cover, soil erosion (e.g., soil pedestal), overstory vegetation condition (type of forest and canopy openness), and soil physical properties (e.g., soil bulk density and particle size). We assumed that high of soil pedestal indicated short term soil erosions by soil splash and related down slope soil movement. Percentages of bare soil in No. 3 tend to greater than ones in No.4. In addition, bare soil slope tended to distributed lower part of hillslopes with > 45° in gradient, where the soil can be transported to streams. Because of the high soil erosion rate in No.3 catchment, suspended sediment and bedload transport in No.3 tended to be greater ones in No.4 catchment. Fingerprinting approach using activities of fallout radionuclides (caesium-137 and excess lead-210) confirmed that some of the fine sediment transport at associated with hillslope soil surface erosion. Findings of this study suggested that processes of catchment scale fine sediment depending on the linkages between hillslope and channels.

  13. Quantifying Forest and Coastal Disturbance from Industrial Mining Using Satellite Time Series Analysis Under Very Cloudy Conditions

    NASA Astrophysics Data System (ADS)

    Alonzo, M.; Van Den Hoek, J.; Ahmed, N.

    2015-12-01

    The open-pit Grasberg mine, located in the highlands of Western Papua, Indonesia, and operated by PT Freeport Indonesia (PT-FI), is among the world's largest in terms of copper and gold production. Over the last 27 years, PT-FI has used the Ajkwa River to transport an estimated 1.3 billion tons of tailings from the mine into the so-called Ajkwa Deposition Area (ADA). The ADA is the product of aggradation and lateral expansion of the Ajkwa River into the surrounding lowland rainforest and mangroves, which include species important to the livelihoods of indigenous Papuans. Mine tailings that do not settle in the ADA disperse into the Arafura Sea where they increase levels of suspended particulate matter (SPM) and associated concentrations of dissolved copper. Despite the mine's large-scale operations, ecological impact of mine tailings deposition on the forest and estuarial ecosystems have received minimal formal study. While ground-based inquiries are nearly impossible due to access restrictions, assessment via satellite remote sensing is promising but hindered by extreme cloud cover. In this study, we characterize ridgeline-to-coast environmental impacts along the Ajkwa River, from the Grasberg mine to the Arafura Sea between 1987 and 2014. We use "all available" Landsat TM and ETM+ images collected over this time period to both track pixel-level vegetation disturbance and monitor changes in coastal SPM levels. Existing temporal segmentation algorithms are unable to assess both acute and protracted trajectories of vegetation change due to pervasive cloud cover. In response, we employ robust, piecewise linear regression on noisy vegetation index (NDVI) data in a manner that is relatively insensitive to atmospheric contamination. Using this disturbance detection technique we constructed land cover histories for every pixel, based on 199 image dates, to differentiate processes of vegetation decline, disturbance, and regrowth. Using annual reports from PT-FI, we show

  14. Temozolomide-Induced Shrinkage of Invasive Pituitary Adenoma in Patient with Nelson's Syndrome: A Case Report and Review of the Literature

    PubMed Central

    Kurowska, Maria; Nowakowski, Andrzej; Zieliński, Grzegorz; Malicka, Joanna; Tarach, Jerzy S.; Maksymowicz, Maria; Denew, Piotr

    2015-01-01

    Introduction. Invasive tumours in Nelson's syndrome need aggressive therapy. Recent reports have documented the efficacy of temozolomide (TMZ) in the treatment of adenomas resistant to conventional management. Objective. The review of the literature concerning TMZ treatment of atypical corticotroph adenomas and a case study of 56-year-old woman who developed Nelson's syndrome. Treatment Proceeding. The patient with Cushing's disease underwent transsphenoidal adenomectomy followed by a 27-month-long period of remission. Due to a regrowth of the tumor, she underwent two reoperations followed by stereotactic radiotherapy. Because of treatment failures, bilateral adrenalectomy was performed. Then she developed Nelson's syndrome. A fourth transsphenoidal adenomectomy was performed, but there was a rapid recurrence. Five months later, she underwent a right frontotemporal craniotomy. Due to a rapid regrowth of the tumour, the patient did not receive gamma-knife therapy and was treated with cabergoline and somatostatin analogue for some time. Only TMZ therapy resulted in marked clinical, biochemical, and radiological improvement. To date, this is the first case of invasive corticotroph adenoma in Nelson's syndrome treated with temozolomide in Poland. Conclusion. In our opinion, temozolomide can be an effective treatment option of invasive adenomas in Nelson's syndrome. PMID:26221547

  15. Forest health and global change.

    PubMed

    Trumbore, S; Brando, P; Hartmann, H

    2015-08-21

    Humans rely on healthy forests to supply energy, building materials, and food and to provide services such as storing carbon, hosting biodiversity, and regulating climate. Defining forest health integrates utilitarian and ecosystem measures of forest condition and function, implemented across a range of spatial scales. Although native forests are adapted to some level of disturbance, all forests now face novel stresses in the form of climate change, air pollution, and invasive pests. Detecting how intensification of these stresses will affect the trajectory of forests is a major scientific challenge that requires developing systems to assess the health of global forests. It is particularly critical to identify thresholds for rapid forest decline, because it can take many decades for forests to restore the services that they provide. PMID:26293952

  16. Occurrence of Phytophthora plurivora and other Phytophthora species in oak forests of southern Poland and their association with site conditions and the health status of trees.

    PubMed

    Jankowiak, R; Stępniewska, H; Bilański, P; Kolařík, M

    2014-11-01

    Phytophthora plurivora and other Phytophthora species are known to be serious pathogens of forest trees. Little is known, however, about the presence of P. plurivora in Polish oak forests and their role in oak decline. The aims of this study were to identify P. plurivora in healthy and declining Quercus robur stands in southern Poland and to demonstrate the relationship between different site factors and the occurrence of P. plurivora. In addition, the virulence of P. plurivora and other Phytophthora species was evaluated through inoculations using 2-year-old oak seedlings. Rhizosphere soil was investigated from 39 oak stands representing different healthy tree statuses. The morphology and DNA sequences of the internal transcribed spacer regions (ITS) of the ribosomal DNA and the mitochondrial cox1 gene were used for identifications. P. plurivora, an oak fine root pathogen, was isolated from rhizosphere soil samples in 6 out of 39 stands. Additionally, Phytophthora cambivora, Phytophthora polonica and Phytophthora rosacearum-like were also obtained from several stands. The results showed a significant association between the presence of P. plurivora and the health status of oak trees. Similar relationships were also observed for all identified Phytophthora species. In addition, there was evidence for a connection between the presence of all identified Phytophthora species and some site conditions. Phytophthora spp. occurred more frequently in declining stands and in silt loam and sandy loam soils with pH ≥ 3.66. P. plurivora and P. cambivora were the only species capable of killing whole plants, producing extensive necrosis on seedling stems.

  17. Amphibian Beta Diversity in the Brazilian Atlantic Forest: Contrasting the Roles of Historical Events and Contemporary Conditions at Different Spatial Scales

    PubMed Central

    da Silva, Fernando Rodrigues; Almeida-Neto, Mário; Arena, Mariana Victorino Nicolosi

    2014-01-01

    Current patterns of biodiversity distribution result from a combination of historical and contemporary processes. Here, we compiled checklists of amphibian species to assess the roles of long-term climate stability (Quaternary oscillations), contemporary environmental gradients and geographical distance as determinants of change in amphibian taxonomic and phylogenetic composition in the Brazilian Atlantic Forest. We calculated beta diversity as both variation in species composition (CBD) and phylogenetic differentiation (PBD) among the assemblages. In both cases, overall beta diversity was partitioned into two basic components: species replacement and difference in species richness. Our results suggest that the CBD and PBD of amphibians are determined by spatial turnover. Geographical distance, current environmental gradients and long-term climatic conditions were complementary predictors of the variation in CBD and PBD of amphibian species. Furthermore, the turnover components between sites from different regions and between sites within the stable region were greater than between sites within the unstable region. On the other hand, the proportion of beta-diversity due to species richness difference for both CBD and PBD was higher between sites in the unstable region than between sites in the stable region. The high turnover components from CBD and PBD between sites in unstable vs stable regions suggest that these distinct regions have different biogeographic histories. Sites in the stable region shared distinct clades that might have led to greater diversity, whereas sites in the unstable region shared close relatives. Taken together, these results indicate that speciation, environmental filtering and limited dispersal are complementary drivers of beta-diversity of amphibian assemblages in the Brazilian Atlantic Forest. PMID:25295514

  18. Foliar photochemical processes and carbon metabolism under favourable and adverse winter conditions in a Mediterranean mixed forest, Catalonia (Spain)

    NASA Astrophysics Data System (ADS)

    Sperlich, D.; Chang, C. T.; Peñuelas, J.; Gracia, C.; Sabaté, S.

    2014-06-01

    Evergreen trees in the Mediterranean region must cope with a wide range of environmental stresses from summer drought to winter cold. The mildness of Mediterranean winters can periodically lead to favourable environmental conditions above the threshold for a positive carbon balance, benefitting evergreen woody species more than deciduous ones. The comparatively lower solar energy input in winter decreases the foliar light saturation point. This leads to a higher susceptibility to photoinhibitory stress especially when chilly (< 12 °C) or freezing temperatures (< 0 °C) coincide with clear skies and relatively high solar irradiances. Nonetheless, the advantage of evergreen species that are able to photosynthesize all year round where a significant fraction can be attributed to winter months, compensates for the lower carbon uptake during spring and summer in comparison to deciduous species. We investigated the ecophysiological behaviour of three co-occurring mature evergreen tree species (Quercus ilex L., Pinus halepensis Mill., and Arbutus unedo L.) during a period of mild winter conditions and their responses to a sudden cold period. The state of the photosynthetic machinery in both periods was thus tested by estimating the foliar photosynthetic potential with CO2 response curves in parallel with chlorophyll fluorescence measurements. The studied evergreen tree species benefited strongly from mild winter conditions by exhibiting extraordinarily high photosynthetic potentials similar to those under spring conditions. A sudden period of frost, however, negatively affected the photosynthetic apparatus, leading to significant decreases in key physiological parameters such as the maximum carboxylation velocity (Vc, max), the maximum photosynthetic electron transport rate (Jmax), and the optimal fluorometric quantum yield of photosystem II (Fv/Fm). This change persisted for several weeks after the cold period despite the recovery of the temperature to the conditions

  19. Foliar photochemical processes and carbon metabolism under favourable and adverse winter conditions in a Mediterranean mixed forest, Catalonia (Spain)

    NASA Astrophysics Data System (ADS)

    Sperlich, D.; Chang, C. T.; Peñuelas, J.; Gracia, C.; Sabaté, S.

    2014-10-01

    Evergreen trees in the Mediterranean region must cope with a wide range of environmental stresses from summer drought to winter cold. The mildness of Mediterranean winters can periodically lead to favourable environmental conditions above the threshold for a positive carbon balance, benefitting evergreen woody species more than deciduous ones. The comparatively lower solar energy input in winter decreases the foliar light saturation point. This leads to a higher susceptibility to photoinhibitory stress especially when chilly (< 12 °C) or freezing temperatures (< 0 °C) coincide with clear skies and relatively high solar irradiances. Nonetheless, the advantage of evergreen species that are able to photosynthesize all year round where a significant fraction can be attributed to winter months, compensates for the lower carbon uptake during spring and summer in comparison to deciduous species. We investigated the ecophysiological behaviour of three co-occurring mature evergreen tree species (Quercus ilex L., Pinus halepensis Mill., and Arbutus unedo L.). Therefore, we collected twigs from the field during a period of mild winter conditions and after a sudden cold period. After both periods, the state of the photosynthetic machinery was tested in the laboratory by estimating the foliar photosynthetic potential with CO2 response curves in parallel with chlorophyll fluorescence measurements. The studied evergreen tree species benefited strongly from mild winter conditions by exhibiting extraordinarily high photosynthetic potentials. A sudden period of frost, however, negatively affected the photosynthetic apparatus, leading to significant decreases in key physiological parameters such as the maximum carboxylation velocity (Vc, max), the maximum photosynthetic electron transport rate (Jmax), and the optimal fluorometric quantum yield of photosystem II (Fv/Fm). The responses of Vc, max and Jmax were highly species specific, with Q. ilex exhibiting the highest and P

  20. The development of hippocampal-dependent memory functions: Theoretical comments on Jabès and Nelson review (2015)

    PubMed Central

    2015-01-01

    Studies investigating the development of memory processes and their neural substrates have flourished over the last two decades. The review by Jabès and Nelson (2015) adds an important piece to our understanding of the maturation of different elements and circuits within the hippocampal system and their association with the progressive development of hippocampal-dependent memory processes in humans. In this accompanying commentary, we explore some additional connections between the nonhuman primate work and the human data, and take the opportunity to highlight some common and additional interpretations of the results. This commentary makes three points: (1) the recognition processes present in the first few days of life may be linked to the early maturation of the medial temporal cortical areas instead of, or in addition to, the early maturation of the subiculum; (2) recent findings on the differential protracted maturation of spatial relational memory processes in monkeys further support the notion proposed by Jabès and Nelson that this protracted development may reflect progressive maturation of the CA1 field of the hippocampus followed by further maturation of CA3/dentate gyrus; (3) finally, further considerations of the differential maturation of the longitudinal hippocampal axis and of the diencephalon are proposed as additional contributors to the refinement of episodic memory functions during development. PMID:26366027

  1. Assessment and monitoring of recreation impacts and resource conditions on mountain summits: examples from the Northern Forest, USA

    USGS Publications Warehouse

    Monz, Christopher A.; Marion, Jeffrey L.; Goonan, Kelly A.; Manning, Robert E.; Wimpey, Jeremy; Carr, Christopher

    2010-01-01

    Mountain summits present a unique challenge to manage sustainably: they are ecologically important and, in many circumstances, under high demand for recreation and tourism activities. This article presents recent advances in the assessment of resource conditions and visitor disturbance in mountain summit environments, by drawing on examples from a multiyear, interdisciplinary study of summits in the northeastern United States. Primary impact issues as a consequence of visitor use, such as informal trail formation, vegetation disturbance, and soil loss, were addressed via the adaption of protocols from recreation ecology studies to summit environments. In addition, new methodologies were developed that provide measurement sensitivity to change previously unavailable through standard recreation monitoring protocols. Although currently limited in application to the northeastern US summit environments, the methods presented show promise for widespread application wherever summits are in demand for visitor activities.

  2. National technical report on forest health, 1996

    SciTech Connect

    Stolte, K.W.

    1997-10-01

    Forest Health Monitoring (FHM) is a national program designed to determine the status, changes, and trends in indicators of forest condition on an annual basis. The FHM program uses data from ground plots and surveys, aerial surveys, and other biotic data sources and develops analytical approaches to address forest health issues that affect the sustainability of forest ecosystems. This report focuses on 18 States that have ground plots. Six forest health issues were identified by the FHM program in 1996 to evaluate forest health; forest ecosystem fragmentation, forest vitality, key ecosystem processes, plant biodiversity, soil conservation, and wildlife habitat.

  3. Development of a mixed shrub-ponderosa pine community in a natural and treated condition. Forest Service research paper (Final)

    SciTech Connect

    McDonald, P.M.; Fiddler, G.O.

    1995-05-01

    On a medium site in northern California, a mostly shrub community was treated by two manual release techniques and by two herbicides, to study its development in both a natural (control) and treated condition. Survival and growth of planted ponderosa pine seedlings were quantified for 8 to 11 years after initial treatment applications. Treatments included manual release in a 4-foot radius around pine seedlings one, two, and three times; grubbing the entire one-seventh acre plot two times; applying 2,4-D and Velpar herbicides to the entire plot one time; and a control. Data are presented for the most abundant species (greenleaf manzanita), second most abundant species (snowbrush), by the two species combined, and by all 10 shrub species combined. At the end of the study in 1990, manzanita was the most abundant species with 15,267 plants per acre, cover of 24,800 ft, and height of 5.4 feet. Ponderosa pine developed best in plots where the entire area was grubbed twice (mean height of 14.2 feet).

  4. Doug Nelson's Contributions to our Understanding of Young Continent-Continent Collisions

    NASA Astrophysics Data System (ADS)

    Klemperer, S. L.; Brown, L. D.; Jones, A. G.

    2002-12-01

    K. Douglas Nelson, Department Chair and Jessie Page Heroy Professor of Earth Sciences at Syracuse University, died suddenly of heart failure on August 17th, 2002, age 49. At the time of his death he was at the heights of an increasingly distinguished career, and had, just prior to his death, agreed to be an invited speaker in this session of the 2002 Fall AGU meeting. Doug began his professional career as a field structural geologist, writing his PhD on the Newfoundland Appalachians, and as a post-doc in South Island, New Zealand. From there he went to Cornell University to join COCORP; he learned to interpret deep seismic reflection data and became hooked on the value of geophysics to the study of large-scale processes in mountain belts. He became one of the proponents of taking the COCORP methodology overseas, to the world's type example of young, continent-continent collisions, the Himalaya. For 10 years from 1992, by now a faculty member at Syracuse, Doug provided operational and intellectual leadership to the INDEPTH program (International Deep Profiling of Tibet and the Himalaya). His talk in this session would undoubtedly have focused on our new understanding of Tibet that resulted in large part from the work that he led and supervised. From the initial conception of INDEPTH as a single reflection profile across Earth's highest mountain range and largest plateau, the program grew through three major stages to encompass a full range of geophysical and geological surveys in a transect that now reaches from the High Himalaya across Tibet. Doug more than anyone was the enthusiastic integrator in the large multi-national group of investigators (from the U.S., China, Canada and Germany), not bound by a single technique, and best able to synthesize the seemingly disparate observations from all the techniques. In recent years he was particularly interested in the combination of magneto-telluric with seismic results to better constrain interpretation of deep geology

  5. Statement of Facts for 1975 City-Wide Mock Trial Competitions. Georgia Floyd, Individually and as Parent and Next Friend of Minor, Nelson Floyd v. Fix-It Home Remodeling, Inc. and Sam Baldwin.

    ERIC Educational Resources Information Center

    National Inst. for Citizen Education in the Law, Washington, DC.

    Prepared by the District of Columbia Street Law Project for its annual city-wide mock trial competition, this instructional handout provides material for a civil trial over a claim for damages. During an argument, a friend pushed Nelson Floyd against the railing of a porch. Falling onto the concrete below, Nelson was injured with a broken shin…

  6. Stem anatomical characteristics of the climbing palm Desmoncus orthacanthos (Arecaceae) under two natural growth conditions in a tropical forest.

    PubMed

    Quiroz, Joaquín; Orellana, Roger; Canto, Gabriel; Rebollar, Silvia; Herrera-Franco, Pedro

    2008-06-01

    Desmoncus orthacanthos is a Neotropical climbing palm that resembles rattan and therefore has similar potential applications. The genus Desmoncus (subfamily Arecoideae, subtribe Bactridinae) is distributed throughout the Americas, from Veracruz, Mexico, to Brazil and Bolivia. The anatomical characteristics of its support tissue have not been thoroughly studied, although some observations from Central American artisans suggest that the stems collected from undisturbed sites possess better characteristics; these include a good capacity to withstand bending without breaking (i.e., higher fracture strength than plants from disturbed sites). Stem samples were collected from individuals from disturbed and undisturbed sites, at three points along the length of the stem (basal, medium and apical). Collections were made of one ramet from five individuals (n=5) at both sites. Each ramet was divided into three sections: basal, from soil surface to a height of 0.5 m; medium, from a height of 0.5 to 5.0 m; and apical, from a height 5.0 to 10.0 m. An anatomical analysis including vascular bundles, parenchyma elements and fibers was performed in the radial direction and also along the longitudinal direction of the stems. The amount of vascular bundles was greater for samples from undisturbed site stems; the amount of parenchyma cells differ between samples from both sites and the amount of fibers was greater for samples from disturbed site stems. The anatomical structural dimensions were smaller for samples from the undisturbed site stems. These findings partially confirm the artisans' belief and supports the conclusion that microclimatic conditions affect plant anatomical structure.

  7. Evaluation of the Non-Formal Forest Education Sector in the State of North Rhine-Westphalia, Germany: Organisations, Programmes and Framework Conditions

    ERIC Educational Resources Information Center

    Grimm, Anne; Mrosek, Thorsten; Martinsohn, Anna; Schulte, Andreas

    2011-01-01

    Although a large number of different organisations offer various forest education programmes within Germany, specific information (i.e., sectoral and programme content and provision at a state level) is lacking. This study used a survey of all 61 forest education organisations (43 respondents) in the state of North Rhine-Westphalia, Germany, to…

  8. Regulation of polyamine metabolism in Pyropia cinnamomea (W.A. Nelson), an important mechanism for reducing UV-B-induced oxidative damage.

    PubMed

    Schweikert, Katja; Hurd, Catriona L; Sutherland, Judith E; Burritt, David J

    2014-04-01

    It is generally accepted that ultraviolet (UV) radiation can have adverse affects on phototrophic organisms, independent of ozone depletion. The red intertidal seaweed Pyropia cinnamomea W.A. Nelson (previously Porphyra cinnamomea Sutherland et al. 2011), similar to many other intertidal macrophytes, is exposed to high levels of UV radiation on a daily basis due to emersion in the upper littoral zone. It has been shown that seaweeds, like higher plants, respond to an increased activity of antioxidative enzymes when exposed to stress. However, earlier investigations have shown that P. cinnamomea also compensates for stress due to UV radiation by increasing polyamine (PA) levels, especially bound-soluble and bound-insoluble PAs. The PA precursor putrescine (PUT) can be synthesized via two enzymatic pathways: arginine decarboxylase (ADC) and ornithine decarboxylase (ODC). Both of these enzymes showed increased activity in P. cinnamomea under UV stress. In higher plants, ADC is the enzyme responsible for increased PA levels during stress exposure, while ODC is correlated with cell division and reproduction. However, there are contrary findings in the literature. Using two irreversible inhibitors, we identified the enzyme most likely responsible for increased PUT synthesis and therefore increased stress tolerance in P. cinnamomea. Our results show that changes in the PA synthesis pathway in P. cinnamomea under UV stress are based on an increased activity of ADC. When either inhibitor was added, lipid hydroperoxide levels increased even under photosynthetically active radiation, suggesting that PAs are involved in protection mechanisms under normal light conditions as well. We also show that under optimum or low-stress conditions, ODC activity is correlated with PUT synthesis. PMID:26988184

  9. Temporal variability in (13)C of respired CO(2) in a pine and a hardwood forest subject to similar climatic conditions.

    PubMed

    Mortazavi, Behzad; Chanton, Jeffrey P; Prater, James L; Oishi, A Christopher; Oren, Ram; Katul, Gabriel

    2005-01-01

    Temporal variability in the (13)C of foliage (delta(13)C(F)), soil (delta(13)C(S)) and ecosystem (delta(13)C(R)) respired CO(2) was contrasted between a 17.2-m tall evenly aged loblolly pine forest and a 35-m tall unevenly aged mature second growth mixed broadleaf deciduous forest in North Carolina, USA, over a 2-year period. The two forests are located at the Duke Forest within a kilometer of each other and are subject to identical climate and have similar soil types. The delta(13)C(F), collected just prior to dawn, was primarily controlled by the time-lagged vapor pressure deficit (VPD) in both stands; it was used for calculating the ratio of intercellular to ambient CO(2) ( Ci/ Ca). A remarkable similarity was observed in the relationship between Ci/ Ca and time-lagged VPD in these two forests despite large differences in hydraulic characteristics. This similarity emerged as a result of physiological adjustments that compensated for differences in plant hydraulic characteristics, as predicted by a recently proposed equilibrium hypothesis, and has implications to ecophysiological models. We found that in the broadleaf forest, the delta(13)C of forest floor CO(2) efflux dominated the delta(13)C(R), while in the younger pine forest, the delta(13)C of foliage respired CO(2) dominated delta(13)C(R). This dependence resulted in a more variable delta(13)C(R) in the pine forest when compared to the broadleaf forest due to the larger photosynthetic contribution. Given the sensitivity of the atmospheric inversion models to delta(13)C(R), the results demonstrate that these models could be improved by accounting for stand characteristics, in addition to previously recognized effects of moisture availability, when estimating delta(13)C(R).

  10. Helminth parasite communities of two Physalaemus cuvieri Fitzinger, 1826 (Anura: Leiuperidae) populations under different conditions of habitat integrity in the Atlantic Rain Forest of Brazil.

    PubMed

    Aguiar, A; Toledo, G M; Anjos, L A; Silva, R J

    2015-11-01

    Adults of Physalaemus cuvieri were collected and necropsied between November 2009 and January 2010. This was carried out in order to report and compare the helminth fauna associated with two populations of this anuran species from the Brazilian Atlantic rain forest under different conditions of habitat integrity. The hosts from the disturbed area were parasitized with five helminth taxa: Cosmocerca parva, Aplectana sp., Physaloptera sp., Rhabdias sp., Oswaldocruzia subauricularis (Nematoda) and Polystoma cuvieri (Monogenea) while those from the preserved area had four helminth taxa: C. parva, Aplectana sp., Physaloptera sp., Rhabdias sp., and Acanthocephalus saopaulensis (Acanthocephala). Prevalence, mean intensity of infection, mean abundance, mean richness, importance index and dominance frequency of helminth component communities were similar in both areas. The helminth community associated with anurans from the disturbed area had higher diversity than that from the preserved area. This study is the first to report on the acanthocephalan parasites of Ph. cuvieri, and the similarity between helminth fauna composition of two host populations under different selective pressures. PMID:26675914

  11. Pantropical forest hydrology

    NASA Astrophysics Data System (ADS)

    Kumagai, T.; Kanamori, H.; Chappell, N. A.

    2015-12-01

    First, we show pantropical distributions of annual amount and seasonality of precipitation with world tropical forest map, derived from the global-scale gridded data. Then, using the atmospheric water balance method with the global-scale data, we built pantropical maps of evapotranspiration (ET), runoff (Q) and rainfall recycle (from precipitation) ratio (RR). Comparisons of the pantropical gridded-computations of ET, Q and RR with those from pantropical fields (mostly, experimental forest watersheds) data revealed differences in hydrologic component characteristics between temperate and tropical forests and how such tropical hydrologic components are generated. Furthermore, an application of Budyko's Radiation Dryness Index to our pantropical analyses allowed us to consider the limits of world tropical forests and future distribution of tropical forests under climate change conditions.

  12. The role of ash on soil water repellency changes in a Mediterranean area affected by a forest fire: a field conditions study

    NASA Astrophysics Data System (ADS)

    Jiménez-Pinilla, P.; Lozano, E.; Mataix-Solera, J.; Arcenegui, V.; Zavala, L. M.; Jordán, A.; Morugán, A.; Pérez-Bejarano, A.; Bárcenas, G. M.

    2012-04-01

    Soil water repellency (WR) is one of the properties most affected by combustion during a forest fire (Doerr, et al., 2000). The modifications of soil organic matter by the heating and the condensation of distilled organic compounds over mineral surfaces are the main factors responsible..After a fire, a layer of ash covers the soil surface affecting also its wettability; it has been demonstrated that ash can also be water repellent depending on the degree of combustion, and type of plant burned (Bodí, et al., 2011). Ash plays an important role in terms of fertility but also in the hydrology of the affected area. The aim of this study is to assess how ash influences the behaviour of soil WR in the short-term after a forest fire. In July 2011, a forest fire affected an area of 50 has in Gorga, Alicante Province, SE Spain. Immediately after fire plots for monitoring were installed in burned (B) and adjacent control (unburned; C) area. In the burned area two treatments were established: Burned ash (Ba): plots where ash was kept, and Burned without ash (Bwa): plots where ash was removed simulating an ash exportation that sometimes occurs through wind erosion. The main objective being to study was therefore the effect of the ash factor. All of the plots were installed underneath Pinus halepensis specie. The water drop penetration time test (WDPT) was used to measure the persistence of WR over topsoil (surface of A mineral horizon) under field conditions in July (immediately after the fire), and in September, October and December 2011,the last measure being after a very rainy period. Ash samples were collected after fire and WR was also measured in laboratory. As expected, WR in July was the highest measured during the study period both in burned and control soil, being higher (670 ± 289) in burned compared to control area (228 ± 92). The measurements of ash WR in laboratory revealed that 50% of samples were water repellent (mainly in the WDPT classes of 10 and 30 s

  13. 77 FR 1667 - Nelson S. Galgoul, Av. Edison Passess 909, Rio De Janeiro, R.J., Brazil 20531-070, Respondent...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-11

    ..., the most recent being that of August 12, 2011 (76 FR 50,661 (Aug. 16, 2011)), has continued the... Bureau of Industry and Security Nelson S. Galgoul, Av. Edison Passess 909, Rio De Janeiro, R.J., Brazil... a last known address of Av. Edison Passess 909, Rio De Janeiro, R.J., Brazil 20531-070, and...

  14. Does Humor Have an Effect on the Performance of College Freshmen in Improving Scores on the Nelson Denny Reading Post Test?

    ERIC Educational Resources Information Center

    Schiller, Maryann F.

    A study was conducted to investigate the effects of humor on the performance of college freshmen on the Nelson Denny Reading Post Test. The subjects, 36 college freshmen from two developmental reading improvement classes, were randomly assigned to experimental A or B or control sample groups. Students had previously taken forms F and C of the test…

  15. Does Deafness Spell Disaster? An Analysis of the Written English Levels of Deaf Children in the Nelson Mandela Metropole, South Africa

    ERIC Educational Resources Information Center

    Weir, Carolyn; Aylif, Diana

    2014-01-01

    This article presents the findings of an empirical comparative study in the Nelson Mandela Metropole investigating the difference between the written English of deaf children and the written English of hearing children and makes recommendations on how to improve the writing of deaf children. The psycholinguistic approach was used for the…

  16. A comparative analysis of simulated and observed landslide locations triggered by Hurricane Camille in Nelson County, Virginia

    USGS Publications Warehouse

    Morrissey, M.M.; Wieczorek, G.F.; Morgan, B.A.

    2008-01-01

    In 1969, Nelson County, Virginia received up to 71 cm of rain within 12 h starting at 7 p.m. on August 19. The total rainfall from the storm exceeded the 1000-year return period in the region. Several thousands of landslides were induced by rainfall associated with Hurricane Camille causing fatalities and destroying infrastructure. We apply a distributed transient response model for regional slope stability analysis to shallow landslides. Initiation points of over 3000 debris flows and effects of flooding from this storm are applied to the model. Geotechnical data used in the calculations are published data from samples of colluvium. Results from these calculations are compared with field observations such as landslide trigger location and timing of debris flows to assess how well the model predicts the spatial and temporal distribution. of landslide initiation locations. The model predicts many of the initiation locations in areas where debris flows are observed. Copyright ?? 2007 John Wiley & Sons, Ltd.

  17. Dynamics of leaf litter humidity, depth and quantity: two restoration strategies failed to mimic ground microhabitat conditions of a low montane and premontane forest in Costa Rica.

    PubMed

    Barrientos, Zaidett

    2012-09-01

    Little is known about how restoration strategies affect aspects like leaf litter's quantity, depth and humidity. I analyzed leaf litter's quantity, depth and humidity yearly patterns in a primary tropical lower montane wet forest and two restored areas: a 15 year old secondary forest (unassisted restoration) and a 40 year old Cupressus lusitanica plantation (natural understory). The three habitats are located in the Rio Macho Forest Reserve, Costa Rica. Twenty litter samples were taken every three months (April 2009-April 2010) in each habitat; humidity was measured in 439g samples (average), depth and quantity were measured in five points inside 50x50cm plots. None of the restoration strategies reproduced the primary forest leaf litter humidity, depth and quantity yearly patterns. Primary forest leaf litter humidity was higher and more stable (mean=73.2), followed by secondary forest (mean=63.3) and cypress plantation (mean=52.9) (Kruskall-Wallis=77.93, n=232, p=0.00). In the primary (Kruskal-Wallis=31.63, n=78, p<0.001) and secondary (Kruskal-Wallis=11.79, n=75, p=0.008) forest litter accumulation was higher during April due to strong winds. In the primary forest (Kruskal-wallis=21.83, n=78, p<0.001) and the cypress plantation (Kruskal-wallis=39.99, n=80, p<0.001) leaf litter depth was shallow in October because heavy rains compacted it. Depth patterns were different from quantity patterns and described the leaf litter's structure in different ecosystems though the year. September 01.

  18. Climate and Management Controls on Forest Growth and Forest Carbon Balance in the Western United States

    NASA Astrophysics Data System (ADS)

    Kelsey, Katharine Cashman

    Climate change is resulting in a number of rapid changes in forests worldwide. Forests comprise a critical component of the global carbon cycle, and therefore climate-induced changes in forest carbon balance have the potential to create a feedback within the global carbon cycle and affect future trajectories of climate change. In order to further understanding of climate-driven changes in forest carbon balance, I (1) develop a method to improve spatial estimates forest carbon stocks, (2) investigate the effect of climate change and forest management actions on forest recovery and carbon balance following disturbance, and (3) explore the relationship between climate and forest growth, and identify climate-driven trends in forest growth through time, within San Juan National Forest in southwest Colorado, USA. I find that forest carbon estimates based on texture analysis from LandsatTM imagery improve regional forest carbon maps, and this method is particularly useful for estimating carbon stocks in forested regions affected by disturbance. Forest recovery from disturbance is also a critical component of future forest carbon stocks, and my results indicate that both climate and forest management actions have important implications for forest recovery and carbon dynamics following disturbance. Specifically, forest treatments that use woody biomass removed from the forest for electricity production can reduce carbon emissions to the atmosphere, but climate driven changes in fire severity and forest recovery can have the opposite effect on forest carbon stocks. In addition to the effects of disturbance and recovery on forest condition, I also find that climate change is decreasing rates of forest growth in some species, likely in response to warming summer temperatures. These growth declines could result in changes of vegetation composition, or in extreme cases, a shift in vegetation type that would alter forest carbon storage. This work provides insight into both

  19. Full-Waveform, Wide-Swath Lidar Imaging of Forested and Urban Areas in Leaf-On Conditions: Development, Results and Future Direction

    NASA Technical Reports Server (NTRS)

    Blair, James B.; Hofton, M.; Rabine, David; Welch, Wayne; Ramos, Luis; Padden, Phillip

    2003-01-01

    Full-Waveform lidar measurements provide unprecedented views of the vertical and horizontal structure of vegetation and the topography of the Earth s surface. Utilizing a high signal-to-noise ratio lidar system, larger than typical laser footprints (10-20 m), and the recorded time history of interaction between a short-duration (approx. 10 ns) pulse of laser light and the surface of the Earth, full-waveform lidar is able to simultaneously image sub-canopy topography as well as the vertical structure of any overlying vegetation. These data reveal the true 3-D vegetation structure in leaf-on conditions enabling important biophysical parameters such as above-ground biomass to be estimated with unprecedented accuracy. An airborne lidar mission was conducted July-August 2003 in support of the North America Carbon Program. NASA s Laser Vegetation Imaging Sensor (LVIS) was used to image approximately 2,000 km$^2$ in Maine, New Hampshire, Massachusetts and Maryland. Areas with available ground and other data were included (e.g., experimental forests, FLUXNET sites) in order to facilitate as many bio- and geophysical investigations as possible. Data collected included ground elevation and canopy height measurements for each laser footprint, as well as the vertical distribution of intercepted surfaces. Data will be publicly distributed within 6- 12 months of collection. Further details of the mission, including the lidar system technology, the locations of the mapped areas, and examples of the numerous data products that can be derived from the return waveform data products will be presented. Future applications including detection of ground and vegetation canopy changes and a spaceborne implementation of wide-swath, full-waveform imaging lidar will also be discussed.

  20. Variability of Root Exudate δ13C and Fluxes in Relation to Environmental Conditions and Plant Characteristics in a Bottomland Temperate Forest

    NASA Astrophysics Data System (ADS)

    Gougherty, S. W.; Bauer, J. E.; Pohlman, J.

    2015-12-01

    Plant root exudation of organic carbon (OC) is thought to be an important, yet poorly quantified and highly variable component of net primary productivity that influences soil biogeochemistry and ecology. In situ measurements of plant root OC exudation are relatively rare, and δ13C measurements of root exudates are generally lacking. Understanding both exudate fluxes and δ13C relative to other plant components, root characteristics and environmental parameters (e.g., vapor pressure deficit and soil moisture) will lead to better quantitative understanding of atmosphere—plant—soil linkages. We used a field based collection system to obtain root exudates from fine roots (diameter <5mm) over five sampling periods in a ~20 year old bottomland forest in central Ohio, USA. Exudates were analyzed for dissolved OC concentration and δ13C signatures. Exudate flux estimates were made at both the individual root level and also scaled to the entire sampling area. Preliminary data analysis suggests the mean root exudation rate was 26 µmol C g root -1 day-1 and when scaled to the 5600 m2 sampling area represents a mean flux of 4,200 µmol C m-2 day-1 from tree roots. The flux estimates presented here suggest root exudation may account for as much as 6% of net ecosystem production at the field location. Available data also suggests that exudate δ13C is enriched by 1-2 ‰ compared the root material from which exudates were collected. We will also assess the relationship between exudate, root and leaf δ13C, environmental parameters, and C fluxes at the site. If root exudation rate or δ13C varies as a function of environmental conditions this may suggest that heterotrophic remineralization of root exudates is one potential driver of correlations between soil δ13C-CO2 and environmental parameters.

  1. Direct and indirect effects of atmospheric conditions and soil moisture on surface energy partitioning revealed by a prolonged drought at a temperate forest site

    SciTech Connect

    Gu, Lianhong; Meyers, T. P.; Pallardy, Stephen G.; Hanson, Paul J; Yang, Bai; Heuer, Mark; Hosman, K. P.; Riggs, Jeffery S; Sluss, Daniel Wayne; Wullschleger, Stan D

    2006-01-01

    The purpose of this paper is to examine the mechanism that controls the variation of surface energy partitioning between latent and sensible heat fluxes at a temperate deciduous forest site in central Missouri, USA. Taking advantage of multiple micrometeorological and ecophysiological measurements and a prolonged drought in the middle of the 2005 growing season at this site, we studied how soil moisture, atmospheric vapor pressure deficit (VPD), and net radiation affected surface energy partitioning. We stratified these factors to minimize potential confounding effects of correlation among them. We found that all three factors had direct effects on surface energy partitioning, but more important, all three factors also had crucial indirect effects. The direct effect of soil moisture was characterized by a rapid decrease in Bowen ratio with increasing soil moisture when the soil was dry and by insensitivity of Bowen ratio to variations in soil moisture when the soil was wet. However, the rate of decrease in Bowen ratio when the soil was dry and the level of soil moisture above which Bowen ratio became insensitive to changes in soil moisture depended on atmospheric conditions. The direct effect of increased net radiation was to increase Bowen ratio. The direct effect of VPD was very nonlinear: Increased VPD decreased Bowen ratio at low VPD but increased Bowen ratio at high VPD. The indirect effects were much more complicated. Reduced soil moisture weakened the influence of VPD but enhanced the influence of net adiation on surface energy partitioning. Soil moisture also controlled how net radiation influenced the relationship between surface energy partitioning and VPD and how VPD affected the relationship between surface energy partitioning and net radiation. Furthermore, both increased VPD and increased net radiation enhanced the sensitivity of Bowen ratio to changes in soil moisture and the effect of drought on surface energy partitioning. The direct and indirect

  2. China Forest Aboveground Biomass Estimation by Fusion of Inventory and Remote Sensing Data: 1st results from Heilongjiang Province and Yunnan Province

    NASA Astrophysics Data System (ADS)

    Pang, Y.; Li, Z.; Huang, G.; Sun, G.; Cheng, Z.; Zhang, Z.; Zhang, G.

    2013-12-01

    Forests play an irreplaceable role in maintaining regional ecological environment, global carbon balance and mitigating global climate change. Forest aboveground biomass (AGB) is an important indicator of forest carbon stocks. Estimating forest aboveground biomass accurately could significantly reduce the uncertainties in terrestrial ecosystem carbon cycle. LIDAR provides accurate information on the vertical structure of forests (Lefsky et al., 2007; Naesset et al., 2004; Pang et al., 2008). Combining airborne LiDAR and spaceborne LiDAR for regional forest biomass retrieval could provide a more reliable and accurate quantitative information in regional forest biomass estimate (Boudreau et al., 2008; Nelson et al., 2009; Pang et al., 2011; Saatchi et al., 2011). The Heilongjiang Province and Yunnan Province are rich in forest resources and suffers intensive forest management activities for timber products. The Heilongjiang Province is typical in temperate forest and the Yunnan Province contains multiple forest types including tropical forest. These two provinces also have good ground inventory system with thousands of permanent field plots. Two campaign consists of in-situ measurement, airborne Lidar data and spaceborne data fusion were designed and implemented. First results show that i). Both spaceborne lidar and forest inventory data are useful for AGB mapping at province level. ii). The combination of spaceborne lidar and forest inventory data gave better biomass estimation with less bias. iii). A pixel level bias mapping was also proposed and gave spatial explicit map of estimation uncertainties. This method will be investigated further with more reference data and tested in other area.

  3. Western forests and air pollution

    SciTech Connect

    Olson, R.K.; Binkley, D.; Boehm, M.

    1992-01-01

    The book addresses the relationships between air pollution in the western United States and trends in the growth and condition of Western coniferous forests. The major atmospheric pollutants to which forest in the region are exposed are sulfur and nitrogen compounds and ozone. The potential effects of atmospheric pollution on these forests include foliar injury, alteration of growth rates and patterns, soil acidification, shifts in species composition, and modification of the effects of natural stresses.

  4. Changes in biomass, productivity and decomposition along topographical gradients under different geological conditions in tropical lower montane forests on Mount Kinabalu, Borneo.

    PubMed

    Takyu, Masaaki; Aiba, Shin-Ichiro; Kitayama, Kanehiro

    2003-02-01

    We have examined how the structure and function of a forest ecosystem change with topography (lower-slope versus ridge) and how the changes are modified by nutrient availability depending on geological substrate (Quaternary and Tertiary sedimentary rocks and ultrabasic rock) in the tropical montane rain forests of Mt. Kinabalu (Borneo) where climate is humid and aseasonal. Reflecting the difference in site age and parent rock, the pool size of soluble-P and inorganic-N in topsoil decreased from Quaternary sedimentary >Tertiary sedimentary >ultrabasic rock on the lower-slope, and they decreased from the lower-slope to the ridge on all substrates. Forest structural attributes [stature, above-ground biomass, and leaf area index (LAI)] decreased in the order of Quaternary sedimentary >Tertiary sedimentary >ultrabasic rock in association with soil nutrients on the lower-slopes, and decreased upslope consistently on each of the three substrates. Functional attributes [above-ground net primary productivity (ANPP) and decomposition rate] demonstrated similar patterns to structure. ANPP significantly correlated with LAI among the six sites, while net assimilation rate (ANPP divided by LAI assuming an even productivity between above vs below-ground system) was nearly constant. Therefore, ANPP could be explained primarily by LAI. Topographical change in LAI could be explained by leaf mass per area (LMA) combined with stand-level leaf biomass. LMA increased upslope on all substrates in association with the decrease in individual leaf area. Stand-level leaf biomass decreased upslope on all substrates but the Tertiary sedimentary rock. Our study demonstrated that topography and geological substrates interactively affected forest structure and processes. The effect of topography on forest structure and processes was greater on nutrient-rich substrates than on poor substrates, and the effect of geological substrate was greater on lower-slopes than on ridges.

  5. True Grit: In Tracking down the Real Story of a Legendary Hero of the Old West, Vaunda Micheaux Nelson also Nabbed the Coretta Scott King Award

    ERIC Educational Resources Information Center

    Fleishhacker, Joy

    2010-01-01

    When Vaunda Micheaux Nelson donned a black Stetson to become the biographer of Deputy U.S. Marshal Bass Reeves, she had no idea that her square-shooting book about an unsung African-American hero of the Old West would win over a posse of fans and earn her the prestigious 2010 Coretta Scott King (CSK) Author Award. "Bad News for Outlaws" (Lerner,…

  6. Do canopy disturbances drive forest plantations into more natural conditions? — A case study from Can Gio Biosphere Reserve, Viet Nam

    NASA Astrophysics Data System (ADS)

    Vogt, Juliane; Kautz, Markus; Fontalvo Herazo, Martha Liliana; Triet, Tran; Walther, Denny; Saint-Paul, Ulrich; Diele, Karen; Berger, Uta

    2013-11-01

    Large areas of mangrove forests were devastated in South Viet Nam during the second Indochina war. After its end in 1975, extensive reforestation with monocultures took place. Can Gio, one of the biggest replanted sites with about 20,000 ha of mangroves mainly Rhizophora apiculata, was declared a biosphere reserve by the UNESCO in 2000. Although this status now enables progressive forest dynamics, there are still drawbacks resulting from the unnatural character of the plantations. For example, the homogeneous size and age structure as well as the regular arrangement of the planted trees make larger forest stands more vulnerable to synchronized collapsing which can be triggered by stronger winds and storms. A transformation into a more natural forest characterized by a heterogeneous age and size structure and a mixed species composition is of urgent need to avoid a synchronized dieback. In this study we test the capability of natural canopy disturbances (e.g. lightning strikes) to facilitate this transformation.Canopy gaps created by lightning strikes were detected and quantified by remote sensing techniques. SPOT satellite images from the years 2003, 2005 and 2007 provided information about the spatial distribution, size, shape, and formation frequency of the gaps. Lightning strike gaps were identified based on their shape and size. They form small openings (mean: 0.025 ha) and their yearly probability of occurrence was determined to be approximately 0.012 per hectare. Selected gaps were surveyed in the field in 2008 to complement the remote sensing data and to provide information upon forest structure and regeneration.Simulation experiments were carried out with the individual-based KiWi mangrove model for quantifying the influence of different lightning regimes on the vertical and horizontal structure of the R. apiculata plantation. In addition, we conducted simulations with a natural and thus randomly generated forest to compare the structure of the two

  7. Occurrence of odorant polyfunctional thiols in the Super Alpha Tomahawk hop cultivar. Comparison with the thiol-rich Nelson Sauvin bitter variety.

    PubMed

    Gros, Jacques; Nizet, Sabrina; Collin, Sonia

    2011-08-24

    Tomahawk hop (Humulus lupulus) is a recently developed Super Alpha cultivar (14-18% α-acids w/w), already widely used by brewers to impart bitterness and a citrus-like aroma to beer. By comparison with two bitter varieties (Nelson Sauvin and Nugget) and two aromatic ones (Cascade and Saaz), the Tomahawk cultivar showed a very particular terpenoid profile, rich in both α- and β-selinenes (>600 mg/kg IST equiv in total), methyl geranate (>40 mg/kg IST equiv), and geraniol (>200 mg/kg). Tomahawk also proved to contain a wide variety of odorant polyfunctional thiols. The major β-sulfanyl acetate, 3-sulfanyl-2-ethylpropyl acetate, newly identified here, was found at similar levels in the famous Sauvignon-like Nelson Sauvin and Tomahawk varieties (15-44 μg/kg IST equiv). On the other hand, lower levels of total β-sulfanyl alcohols were measured in Tomahawk, although 3-sulfanylhexan-1-ol was found at a similar level and the 3-sulfanyl-4-methylpentan-1-ol previously claimed to be specific to the Nelson Sauvin variety was also evidenced in the Super Alpha cultivar (9-13 μg/kg IST equiv). As revealed by boiling and fermentation, Tomahawk hop also contains very interesting bound polyfunctional thiols that should be investigated for better use by brewers.

  8. Stability and change in forest-based communities: A selected bibliography. Forest Service general technical report

    SciTech Connect

    Richardson, C.W.

    1996-03-01

    This bibliography lists literature dealing with the concept of community stability, the condition of forest-based communities, and the relations between forest management and local community conditions. The emphasis is on forest-based communities in the Pacific Northwest, but citations from across the United States and other industrialized nations, such as Canada, New Zealand, and the Scandinavian countries, also are included.

  9. Global-scale patterns of forest fragmentation

    USGS Publications Warehouse

    Riitters, K.; Wickham, J.; O'Neill, R.; Jones, B.; Smith, E.

    2000-01-01

    We report an analysis of forest fragmentation based on 1-km resolution land-cover maps for the globe. Measurements in analysis windows from 81 km 2 (9 ?? 9 pixels, "small" scale) to 59,049 km 2 (243 ?? 243 pixels, "large" scale) were used to characterize the fragmentation around each forested pixel. We identified six categories of fragmentation (interior, perforated, edge, transitional, patch, and undetermined) from the amount of forest and its occurrence as adjacent forest pixels. Interior forest exists only at relatively small scales; at larger scales, forests are dominated by edge and patch conditions. At the smallest scale, there were significant differences in fragmentation among continents; within continents, there were significant differences among individual forest types. Tropical rain forest fragmentation was most severe in North America and least severe in Europe - Asia. Forest types with a high percentage of perforated conditions were mainly in North America (five types) and Europe - Asia (four types), in both temperate and subtropical regions. Transitional and patch conditions were most common in 11 forest types, of which only a few would be considered as "naturally patchy" (e.g., dry woodland). The five forest types with the highest percentage of interior conditions were in North America; in decreasing order, they were cool rain forest, coniferous, conifer boreal, cool mixed, and cool broadleaf. Copyright ?? 2000 by The Resilience Alliance.

  10. Sensitivity of photosynthetic electron transport to photoinhibition in a temperate deciduous forest canopy: Photosystem II center openness, non-radiative energy dissipation and excess irradiance under field conditions.

    PubMed

    Niinemets U; Kull, O

    2001-08-01

    We used chlorophyll fluorescence techniques to investigate responses of Photosystem II (PSII) quantum yield to light availability in the short term (quantum flux density integrated over the measurement day, Qd) and in the long term (Qd averaged over the season, Qs) in a mixed deciduous forest comprising shade-tolerant and water-stress-sensitive Tilia cordata Mill. in the lower canopy and shade-intolerant and water-stress-resistant Populus tremula L. in the upper canopy. In both species, intrinsic efficiency of PSII in the dark-adapted state (Fv/Fm) was lower during the day than during the night, and the difference in Fv/Fm between day and night increased with increasing Qs. Although the capacity for photosynthetic electron transport increased with increasing Qs in both species, maximum quantum efficiency of PSII in the light-adapted state (alpha) decreased with increasing Qs. At a common Qs, alpha was lower in T. cordata than in P. tremula primarily because of a higher fraction of closed PSII centers, and to a smaller extent because of limited, non-radiative, excitation energy dissipation in the pigment bed in T. cordata. Across both species, photochemical quenching (qP), which measures the openness of PSII centers, varied more than fivefold, but the efficiency of excitation energy capture by open PSII centers (Fv'/Fm'), which is an estimate of non-radiative excitation energy dissipation in PSII antennae, varied by only 50%. Chlorophyll turnover rates increased with increasing irradiance, especially in T. cordata, possibly because of increased photodestruction. Diurnal measurements of PSII quantum yields (PhiPSII) indicated that, under similar environmental conditions, PhiPSII was always lower in the afternoon than in the morning, and the fraction of daily integrated photosynthetic electron transport lost because of diurnal declines in PhiPSII (Delta) increased with increasing Qd. At a common Qd, mean daily PSII center reduction state, the fraction of light in

  11. A New Method for the Spatialization of Forest Cover by Fusing Forest Inventory and MODIS Data

    NASA Astrophysics Data System (ADS)

    Yin, Y.

    2015-12-01

    The acquisition of accurate spatial and temporal data on forest cover is the foundation for the sustainable management and utilization of forest resources. Although forest inventory data can provide accurate statistical information about forest type, such data do not give the specific spatial distribution. Remote sensing data provide accurate spatial information, and vegetation indices provide measures of land surface vegetation cover and growth conditions. By fusing these two sources of data, specific information about the spatial distribution of different types of forest can be obtained. Here, in a case study of Heilongjiang Province, we obtained forest dominant species area from the sixth and seventh national forest inventories and MODIS composite remote sensing data for the same periods to study forest cover by developing a spatialization method. Based on pixel features (such as NDVI and near-infrared reflectance) and their relationships with forest types, thresholds between different forest types in the remote sensing information were set according to the statistical data, which allowed the two sets of data to be fused. As a result, we generated forest cover maps for 2000 and 2005 that show the distribution of four forest types. Taking vegetation map of China as reference data, an error matrix analysis shows that the overall classification consistency reaches 76.7%, but only 70% for evergreen needleleaf forest and mixed forest. This study paves the way for further research on improving the accuracy of forest cover classification accuracy, on expanding the spatial and temporal scales of interest, and on quantifying forest dynamics

  12. Reconstruction of climate, soil, and vegetation conditions of the Srubnaya cultural epoch on the basis of kurgan studies in the Cis-Ural forest-steppe of the Republic of Bashkortostan

    NASA Astrophysics Data System (ADS)

    Prikhod'ko, V. E.; Rohozin, Ye. P.; Chaplygin, M. S.

    2016-09-01

    The reconstruction of soil, vegetation, and climatic conditions for the Srubnaya cultural epoch (3660 ± 40 (date wood), 3860 ± 120 (bones date) was performed on the basis of palynological and paleosol studies with radiocarbon dating of bones and wood fragments from two kurgans in the Cis-Ural forest-steppe of the Republic of Bashkortostan. Morphological features and chemical properties of the modern background soils, the soils formed on the surface of burial mounds (kurgans), and the soils buried under them were characterized. According to palynological data, the climate of this territory in the period of construction of these kurgans was more humid than the modern climate. The paleovegetation of the Srubnaya epoch was represented by mesophilic herbaceous steppes with a lower participation of xerophytic species as compared to the modern steppe and by small forest groves composed of birch and pine trees with some admixture of lime trees. The temperature conditions were close to those at present, or somewhat cooler, which is evidenced by the lower content of pollen of the broadleaved trees. The modern background soils and the soils buried under the kurgans are classified as thin light loamy typical calcareous chernozems; they have similar morphologies and physicochemical properties. However, the reconstructed organic matter content in the upper 50 cm of the buried paleosols is higher than that in the modern soils. This attests to more favorable climatic conditions during the Srubnaya epoch and is in agreement with palynological data.

  13. Isotopic ages from the Nelson region of South Island New Zealand: crustal structure and definition of the Median Tectonic Zone

    NASA Astrophysics Data System (ADS)

    Kimbrough, D. L.; Tulloch, A. J.; Geary, E.; Coombs, D. S.; Landis, C. A.

    1993-10-01

    Plutonic rocks in the Rotoroa Complex and Drumduan Terrane of South Island, New Zealand yield zircon U/Pb dates of 156 and 142 Ma, respectively, that are interpreted as crystallization ages. Hornblende and biotite 40Ar/ 39Ar dates of 140-130 Ma from the Rotoroa represent either emplacement ages, cooling ages or a metamorphic resetting event. These two units crop out between the Brook Street Terrane and the Separation Point Batholith and lack any clear affinity with tectonostratigraphic terranes of the New Zealand Western or Eastern provinces. The Rotoroa Complex and Drumduan Terrane are interpreted as part of a series of dismembered Mesozoic volcanic-plutonic arc complexes that are sandwiched between terranes of the Western and Eastern provinces, occupying a structural position here referred to as the Median Tectonic Zone (MTZ). Correlative units in Fiordland on the opposite side of the Alpine Fault include the Mackay Intrusives, Darran Complex, Largs Terrane, Lochburn Formation and the Halfway Peak Gabbro. Farther south on Stewart Island the Anglern Complex and Paterson Group are part of the same structural belt. The MTZ is an extension of the original concept of the Median Tectonic Line put forth by Landis and Coombs (1967). Dismemberment and juxtaposition of arc magmatic assemblages in the MTZ with Western and Eastern Province terranes is related to large-scale transcurrent faulting in the Early Cretaceous. Its essential features as a regional tectonostratigraphic terrane were established by ~ 117 Ma as indicated by stitching of the Rotoroa Complex to the Takaka Terrane (Western Province) by the Separation Point Batholith (117-114 Ma). The Echinus Granite yields a 310 Ma U/Pb zircon crystallization age that suggests the granite and associated gneisses are part of the Western Province which may constrain the position of the western margin of the MTZ near Nelson City.

  14. Effect of hydrological conditions on nitrous oxide, methane, and carbon dioxide dynamics in a bottomland hardwood forest and its implication for soil carbon sequestration

    USGS Publications Warehouse

    Yu, K.; Faulkner, S.P.; Baldwin, M.J.

    2008-01-01

    This study was conducted at three locations in a bottomland hardwood forest with a distinct elevation and hydrological gradient: ridge (high, dry), transition, and swamp (low, wet). At each location, concentrations of soil greenhouse gases (N2O, CH4 , and CO2), their fluxes to the atmosphere, and soil redox potential (Eh) were measured bimonthly, while the water table was monitored every day. Results show that soil Eh was significantly (P transition > ridge location. The ratio CO2/CH4 production in soil is a critical factor for evaluating the overall benefit of soil C sequestration, which can be greatly offset by CH4 production and emission. ?? Journal compilation ?? 2008 Blackwell Publishing.

  15. p-hacking by post hoc selection with multiple opportunities: Detectability by skewness test?: Comment on Simonsohn, Nelson, and Simmons (2014).

    PubMed

    Ulrich, Rolf; Miller, Jeff

    2015-12-01

    Simonsohn, Nelson, and Simmons (2014) have suggested a novel test to detect p-hacking in research, that is, when researchers report excessive rates of "significant effects" that are truly false positives. Although this test is very useful for identifying true effects in some cases, it fails to identify false positives in several situations when researchers conduct multiple statistical tests (e.g., reporting the most significant result). In these cases, p-curves are right-skewed, thereby mimicking the existence of real effects even if no effect is actually present. PMID:26595841

  16. p-hacking by post hoc selection with multiple opportunities: Detectability by skewness test?: Comment on Simonsohn, Nelson, and Simmons (2014).

    PubMed

    Ulrich, Rolf; Miller, Jeff

    2015-12-01

    Simonsohn, Nelson, and Simmons (2014) have suggested a novel test to detect p-hacking in research, that is, when researchers report excessive rates of "significant effects" that are truly false positives. Although this test is very useful for identifying true effects in some cases, it fails to identify false positives in several situations when researchers conduct multiple statistical tests (e.g., reporting the most significant result). In these cases, p-curves are right-skewed, thereby mimicking the existence of real effects even if no effect is actually present.

  17. [Nelson Rockefeller and the activities of the American International Association for Economic and Social Development: the debate concerning mission and imperialism in Brazil, 1946-1961].

    PubMed

    Silva, Claiton Marcio da

    2013-10-01

    The article analyzes the bibliography on Nelson Rockefeller and the activities of the American International Association for Economic and Social Development in Brazil. It describes optimistic interpretations of Rockefeller's and the association's work, as well as the nationalist stream of thought, which characterized him as one of the chief representatives of U.S. imperialism, both as a political representative in the 1960s and as the mind behind endeavors of interest to the private sector. It is shown that at the individual and agency levels alike, these initiatives involved direct ties to the local elites, who influenced the reshaping and operationalization of technical cooperation projects.

  18. Forest health monitoring: Field methods guide

    SciTech Connect

    Tallent-Halsell, N.G.

    1994-10-01

    This guide is intended to instruct Forest Health Monitors when collecting data on forest health indicators; site condition, growth and regeneration, crown condition, tree damage and mortality assessment, photosynthetically active radiation, vegetation structure, ozone bioindicator species, lichen community structure and field logistics. This guide contains information on measuring, observing and recording data related to the above listed forest health indicators. Pertinent quality assurance information is also included.

  19. Does Exurban Housing Development Affect the Physiological Condition of Forest-Breeding Songbirds? A Case Study of Ovenbirds (Seiurus aurocapillus) in the Largest Protected Area in the Contiguous United States.

    PubMed

    Seewagen, Chad L; Glennon, Michale; Smith, Susan B

    2015-01-01

    Exurban development (low-density development in rural areas) can significantly alter wildlife community composition, but it is largely unknown whether it also affects wildlife at the individual level. We investigated individual-level impacts of exurban development in New York State's Adirondack Park by comparing the physiological condition of 62 male ovenbirds (Seiurus aurocapillus) breeding in forests with low-density housing development with those in contiguous forests. We used hematocrit (HCT) volume and plasma triglyceride (TRIG) levels to compare energetic condition, plasma uric acid (UA) and total plasma protein (TPP) levels to compare diet quality, and heterophil∶lymphocyte ratios (H∶L) to compare chronic stress. HCT was the only parameter to differ, with birds near houses exhibiting lower values. The comparable TRIG, UA, and TPP that we found between treatment types suggest that ovenbird food quality and availability are unaffected by exurban development in our study area. Similar H∶L suggests that homeowner activities do not significantly change chronic stressors faced by breeding male ovenbirds. We also found no difference in body mass, body size, or age ratio to indicate that habitats in either treatment type were in higher demand or more difficult to acquire. Although our results suggest that exurban development does not reduce habitat quality for male ovenbirds in a way that affects their condition, we caution that it may still ultimately reduce fitness by attracting synanthropic predators. Further work is needed to better understand the impacts of exurban development on wildlife at all levels and provide science-based information needed to meet conservation challenges in rapidly developing exurban areas.

  20. Does Exurban Housing Development Affect the Physiological Condition of Forest-Breeding Songbirds? A Case Study of Ovenbirds (Seiurus aurocapillus) in the Largest Protected Area in the Contiguous United States.

    PubMed

    Seewagen, Chad L; Glennon, Michale; Smith, Susan B

    2015-01-01

    Exurban development (low-density development in rural areas) can significantly alter wildlife community composition, but it is largely unknown whether it also affects wildlife at the individual level. We investigated individual-level impacts of exurban development in New York State's Adirondack Park by comparing the physiological condition of 62 male ovenbirds (Seiurus aurocapillus) breeding in forests with low-density housing development with those in contiguous forests. We used hematocrit (HCT) volume and plasma triglyceride (TRIG) levels to compare energetic condition, plasma uric acid (UA) and total plasma protein (TPP) levels to compare diet quality, and heterophil∶lymphocyte ratios (H∶L) to compare chronic stress. HCT was the only parameter to differ, with birds near houses exhibiting lower values. The comparable TRIG, UA, and TPP that we found between treatment types suggest that ovenbird food quality and availability are unaffected by exurban development in our study area. Similar H∶L suggests that homeowner activities do not significantly change chronic stressors faced by breeding male ovenbirds. We also found no difference in body mass, body size, or age ratio to indicate that habitats in either treatment type were in higher demand or more difficult to acquire. Although our results suggest that exurban development does not reduce habitat quality for male ovenbirds in a way that affects their condition, we caution that it may still ultimately reduce fitness by attracting synanthropic predators. Further work is needed to better understand the impacts of exurban development on wildlife at all levels and provide science-based information needed to meet conservation challenges in rapidly developing exurban areas. PMID:26052638

  1. Comparing Forests across Climates and Biomes: Qualitative Assessments, Reference Forests and Regional Intercomparisons

    PubMed Central

    Salk, Carl F.; Frey, Ulrich; Rusch, Hannes

    2014-01-01

    Communities, policy actors and conservationists benefit from understanding what institutions and land management regimes promote ecosystem services like carbon sequestration and biodiversity conservation. However, the definition of success depends on local conditions. Forests' potential carbon stock, biodiversity and rate of recovery following disturbance are known to vary with a broad suite of factors including temperature, precipitation, seasonality, species' traits and land use history. Methods like tracking over-time changes within forests, or comparison with “pristine” reference forests have been proposed as means to compare the structure and biodiversity of forests in the face of underlying differences. However, data from previous visits or reference forests may be unavailable or costly to obtain. Here, we introduce a new metric of locally weighted forest intercomparison to mitigate the above shortcomings. This method is applied to an international database of nearly 300 community forests and compared with previously published techniques. It is particularly suited to large databases where forests may be compared among one another. Further, it avoids problematic comparisons with old-growth forests which may not resemble the goal of forest management. In most cases, the different methods produce broadly congruent results, suggesting that researchers have the flexibility to compare forest conditions using whatever type of data is available. Forest structure and biodiversity are shown to be independently measurable axes of forest condition, although users' and foresters' estimations of seemingly unrelated attributes are highly correlated, perhaps reflecting an underlying sentiment about forest condition. These findings contribute new tools for large-scale analysis of ecosystem condition and natural resource policy assessment. Although applied here to forestry, these techniques have broader applications to classification and evaluation problems using

  2. Comparing forests across climates and biomes: qualitative assessments, reference forests and regional intercomparisons.

    PubMed

    Salk, Carl F; Frey, Ulrich; Rusch, Hannes

    2014-01-01

    Communities, policy actors and conservationists benefit from understanding what institutions and land management regimes promote ecosystem services like carbon sequestration and biodiversity conservation. However, the definition of success depends on local conditions. Forests' potential carbon stock, biodiversity and rate of recovery following disturbance are known to vary with a broad suite of factors including temperature, precipitation, seasonality, species' traits and land use history. Methods like tracking over-time changes within forests, or comparison with "pristine" reference forests have been proposed as means to compare the structure and biodiversity of forests in the face of underlying differences. However, data from previous visits or reference forests may be unavailable or costly to obtain. Here, we introduce a new metric of locally weighted forest intercomparison to mitigate the above shortcomings. This method is applied to an international database of nearly 300 community forests and compared with previously published techniques. It is particularly suited to large databases where forests may be compared among one another. Further, it avoids problematic comparisons with old-growth forests which may not resemble the goal of forest management. In most cases, the different methods produce broadly congruent results, suggesting that researchers have the flexibility to compare forest conditions using whatever type of data is available. Forest structure and biodiversity are shown to be independently measurable axes of forest condition, although users' and foresters' estimations of seemingly unrelated attributes are highly correlated, perhaps reflecting an underlying sentiment about forest condition. These findings contribute new tools for large-scale analysis of ecosystem condition and natural resource policy assessment. Although applied here to forestry, these techniques have broader applications to classification and evaluation problems using crowdsourced

  3. Comparing forests across climates and biomes: qualitative assessments, reference forests and regional intercomparisons.

    PubMed

    Salk, Carl F; Frey, Ulrich; Rusch, Hannes

    2014-01-01

    Communities, policy actors and conservationists benefit from understanding what institutions and land management regimes promote ecosystem services like carbon sequestration and biodiversity conservation. However, the definition of success depends on local conditions. Forests' potential carbon stock, biodiversity and rate of recovery following disturbance are known to vary with a broad suite of factors including temperature, precipitation, seasonality, species' traits and land use history. Methods like tracking over-time changes within forests, or comparison with "pristine" reference forests have been proposed as means to compare the structure and biodiversity of forests in the face of underlying differences. However, data from previous visits or reference forests may be unavailable or costly to obtain. Here, we introduce a new metric of locally weighted forest intercomparison to mitigate the above shortcomings. This method is applied to an international database of nearly 300 community forests and compared with previously published techniques. It is particularly suited to large databases where forests may be compared among one another. Further, it avoids problematic comparisons with old-growth forests which may not resemble the goal of forest management. In most cases, the different methods produce broadly congruent results, suggesting that researchers have the flexibility to compare forest conditions using whatever type of data is available. Forest structure and biodiversity are shown to be independently measurable axes of forest condition, although users' and foresters' estimations of seemingly unrelated attributes are highly correlated, perhaps reflecting an underlying sentiment about forest condition. These findings contribute new tools for large-scale analysis of ecosystem condition and natural resource policy assessment. Although applied here to forestry, these techniques have broader applications to classification and evaluation problems using crowdsourced

  4. The impact of forest structure and light utilization on carbon cycling in tropical forests

    NASA Astrophysics Data System (ADS)

    Morton, D. C.; Longo, M.; Leitold, V.; Keller, M. M.

    2015-12-01

    Light competition is a fundamental organizing principle of forest ecosystems, and interactions between forest structure and light availability provide an important constraint on forest productivity. Tropical forests maintain a dense, multi-layered canopy, based in part on abundant diffuse light reaching the forest understory. Climate-driven changes in light availability, such as more direct illumination during drought conditions, therefore alter the potential productivity of forest ecosystems during such events. Here, we used multi-temporal airborne lidar data over a range of Amazon forest conditions to explore the influence of forest structure on gross primary productivity (GPP). Our analysis combined lidar-based observations of canopy illumination and turnover in the Ecosystem Demography model (ED, version 2.2). The ED model was updated to specifically account for regional differences in canopy and understory illumination using lidar-derived measures of canopy light environments. Model simulations considered the influence of forest structure on GPP over seasonal to decadal time scales, including feedbacks from differential productivity between illuminated and shaded canopy trees on mortality rates and forest composition. Finally, we constructed simple scenarios with varying diffuse and direct illumination to evaluate the potential for novel plant-climate interactions under scenarios of climate change. Collectively, the lidar observations and model simulations underscore the need to account for spatial heterogeneity in the vertical structure of tropical forests to constrain estimates of tropical forest productivity under current and future climate conditions.

  5. Forests & Trees.

    ERIC Educational Resources Information Center

    Gage, Susan

    1989-01-01

    This newsletter discusses the disappearance of the world's forests and the resulting environmental problems of erosion and flooding; loss of genetic diversity; climatic changes such as less rainfall, and intensifying of the greenhouse effect; and displacement and destruction of indigenous cultures. The articles, lessons, and activities are…

  6. Forest Imaging

    NASA Technical Reports Server (NTRS)

    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.

  7. Forest discrimination with multipolarization imaging radar

    NASA Technical Reports Server (NTRS)

    Ford, J. P.; Wickland, D. E.

    1985-01-01

    The relations between polarization signatures and biophysical characteristics through a range of different forest environments were investigated using airborne synthetic-aperture (SAR) images acquired at L-band on March 1, 1984 in South Carolina. SAR data acquired in four linear polarization states with 10-m spatial resolution were encoded as color composite images and compared to US Forest Service forest stand data. The most useful correlative forest data were stand basal area, forest age, site condition index, and forest management type. It is found that the multipolarization images discriminate variation in tree density or difference in the amount of understory, but no evidence has been found for discrimination between evergreen and deciduous forest types.

  8. Forest fires

    SciTech Connect

    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.

  9. CTFS-ForestGEO: a worldwide network monitoring forests in an era of global change.

    PubMed

    Anderson-Teixeira, Kristina J; Davies, Stuart J; Bennett, Amy C; Gonzalez-Akre, Erika B; Muller-Landau, Helene C; Wright, S Joseph; Abu Salim, Kamariah; Almeyda Zambrano, Angélica M; Alonso, Alfonso; Baltzer, Jennifer L; Basset, Yves; Bourg, Norman A; Broadbent, Eben N; Brockelman, Warren Y; Bunyavejchewin, Sarayudh; Burslem, David F R P; Butt, Nathalie; Cao, Min; Cardenas, Dairon; Chuyong, George B; Clay, Keith; Cordell, Susan; Dattaraja, Handanakere S; Deng, Xiaobao; Detto, Matteo; Du, Xiaojun; Duque, Alvaro; Erikson, David L; Ewango, Corneille E N; Fischer, Gunter A; Fletcher, Christine; Foster, Robin B; Giardina, Christian P; Gilbert, Gregory S; Gunatilleke, Nimal; Gunatilleke, Savitri; Hao, Zhanqing; Hargrove, William W; Hart, Terese B; Hau, Billy C H; He, Fangliang; Hoffman, Forrest M; Howe, Robert W; Hubbell, Stephen P; Inman-Narahari, Faith M; Jansen, Patrick A; Jiang, Mingxi; Johnson, Daniel J; Kanzaki, Mamoru; Kassim, Abdul Rahman; Kenfack, David; Kibet, Staline; Kinnaird, Margaret F; Korte, Lisa; Kral, Kamil; Kumar, Jitendra; Larson, Andrew J; Li, Yide; Li, Xiankun; Liu, Shirong; Lum, Shawn K Y; Lutz, James A; Ma, Keping; Maddalena, Damian M; Makana, Jean-Remy; Malhi, Yadvinder; Marthews, Toby; Mat Serudin, Rafizah; McMahon, Sean M; McShea, William J; Memiaghe, Hervé R; Mi, Xiangcheng; Mizuno, Takashi; Morecroft, Michael; Myers, Jonathan A; Novotny, Vojtech; de Oliveira, Alexandre A; Ong, Perry S; Orwig, David A; Ostertag, Rebecca; den Ouden, Jan; Parker, Geoffrey G; Phillips, Richard P; Sack, Lawren; Sainge, Moses N; Sang, Weiguo; Sri-Ngernyuang, Kriangsak; Sukumar, Raman; Sun, I-Fang; Sungpalee, Witchaphart; Suresh, Hebbalalu Sathyanarayana; Tan, Sylvester; Thomas, Sean C; Thomas, Duncan W; Thompson, Jill; Turner, Benjamin L; Uriarte, Maria; Valencia, Renato; Vallejo, Marta I; Vicentini, Alberto; Vrška, Tomáš; Wang, Xihua; Wang, Xugao; Weiblen, George; Wolf, Amy; Xu, Han; Yap, Sandra; Zimmerman, Jess

    2015-02-01

    Global change is impacting forests worldwide, threatening biodiversity and ecosystem services including climate regulation. Understanding how forests respond is critical to forest conservation and climate protection. This review describes an international network of 59 long-term forest dynamics research sites (CTFS-ForestGEO) useful for characterizing forest responses to global change. Within very large plots (median size 25 ha), all stems ≥ 1 cm diameter are identified to species, mapped, and regularly recensused according to standardized protocols. CTFS-ForestGEO spans 25 °S-61 °N latitude, is generally representative of the range of bioclimatic, edaphic, and topographic conditions experienced by forests worldwide, and is the only forest monitoring network that applies a standardized protocol to each of the world's major forest biomes. Supplementary standardized measurements at subsets of the sites provide additional information on plants, animals, and ecosystem and environmental variables. CTFS-ForestGEO sites are experiencing multifaceted anthropogenic global change pressures including warming (average 0.61 °C), changes in precipitation (up to ± 30% change), atmospheric deposition of nitrogen and sulfur compounds (up to 3.8 g N m(-2) yr(-1) and 3.1 g S m(-2) yr(-1)), and forest fragmentation in the surrounding landscape (up to 88% reduced tree cover within 5 km). The broad suite of measurements made at CTFS-ForestGEO sites makes it possible to investigate the complex ways in which global change is impacting forest dynamics. Ongoing research across the CTFS-ForestGEO network is yielding insights into how and why the forests are changing, and continued monitoring will provide vital contributions to understanding worldwide forest diversity and dynamics in an era of global change.

  10. CTFS-ForestGEO: a worldwide network monitoring forests in an era of global change.

    PubMed

    Anderson-Teixeira, Kristina J; Davies, Stuart J; Bennett, Amy C; Gonzalez-Akre, Erika B; Muller-Landau, Helene C; Wright, S Joseph; Abu Salim, Kamariah; Almeyda Zambrano, Angélica M; Alonso, Alfonso; Baltzer, Jennifer L; Basset, Yves; Bourg, Norman A; Broadbent, Eben N; Brockelman, Warren Y; Bunyavejchewin, Sarayudh; Burslem, David F R P; Butt, Nathalie; Cao, Min; Cardenas, Dairon; Chuyong, George B; Clay, Keith; Cordell, Susan; Dattaraja, Handanakere S; Deng, Xiaobao; Detto, Matteo; Du, Xiaojun; Duque, Alvaro; Erikson, David L; Ewango, Corneille E N; Fischer, Gunter A; Fletcher, Christine; Foster, Robin B; Giardina, Christian P; Gilbert, Gregory S; Gunatilleke, Nimal; Gunatilleke, Savitri; Hao, Zhanqing; Hargrove, William W; Hart, Terese B; Hau, Billy C H; He, Fangliang; Hoffman, Forrest M; Howe, Robert W; Hubbell, Stephen P; Inman-Narahari, Faith M; Jansen, Patrick A; Jiang, Mingxi; Johnson, Daniel J; Kanzaki, Mamoru; Kassim, Abdul Rahman; Kenfack, David; Kibet, Staline; Kinnaird, Margaret F; Korte, Lisa; Kral, Kamil; Kumar, Jitendra; Larson, Andrew J; Li, Yide; Li, Xiankun; Liu, Shirong; Lum, Shawn K Y; Lutz, James A; Ma, Keping; Maddalena, Damian M; Makana, Jean-Remy; Malhi, Yadvinder; Marthews, Toby; Mat Serudin, Rafizah; McMahon, Sean M; McShea, William J; Memiaghe, Hervé R; Mi, Xiangcheng; Mizuno, Takashi; Morecroft, Michael; Myers, Jonathan A; Novotny, Vojtech; de Oliveira, Alexandre A; Ong, Perry S; Orwig, David A; Ostertag, Rebecca; den Ouden, Jan; Parker, Geoffrey G; Phillips, Richard P; Sack, Lawren; Sainge, Moses N; Sang, Weiguo; Sri-Ngernyuang, Kriangsak; Sukumar, Raman; Sun, I-Fang; Sungpalee, Witchaphart; Suresh, Hebbalalu Sathyanarayana; Tan, Sylvester; Thomas, Sean C; Thomas, Duncan W; Thompson, Jill; Turner, Benjamin L; Uriarte, Maria; Valencia, Renato; Vallejo, Marta I; Vicentini, Alberto; Vrška, Tomáš; Wang, Xihua; Wang, Xugao; Weiblen, George; Wolf, Amy; Xu, Han; Yap, Sandra; Zimmerman, Jess

    2015-02-01

    Global change is impacting forests worldwide, threatening biodiversity and ecosystem services including climate regulation. Understanding how forests respond is critical to forest conservation and climate protection. This review describes an international network of 59 long-term forest dynamics research sites (CTFS-ForestGEO) useful for characterizing forest responses to global change. Within very large plots (median size 25 ha), all stems ≥ 1 cm diameter are identified to species, mapped, and regularly recensused according to standardized protocols. CTFS-ForestGEO spans 25 °S-61 °N latitude, is generally representative of the range of bioclimatic, edaphic, and topographic conditions experienced by forests worldwide, and is the only forest monitoring network that applies a standardized protocol to each of the world's major forest biomes. Supplementary standardized measurements at subsets of the sites provide additional information on plants, animals, and ecosystem and environmental variables. CTFS-ForestGEO sites are experiencing multifaceted anthropogenic global change pressures including warming (average 0.61 °C), changes in precipitation (up to ± 30% change), atmospheric deposition of nitrogen and sulfur compounds (up to 3.8 g N m(-2) yr(-1) and 3.1 g S m(-2) yr(-1)), and forest fragmentation in the surrounding landscape (up to 88% reduced tree cover within 5 km). The broad suite of measurements made at CTFS-ForestGEO sites makes it possible to investigate the complex ways in which global change is impacting forest dynamics. Ongoing research across the CTFS-ForestGEO network is yielding insights into how and why the forests are changing, and continued monitoring will provide vital contributions to understanding worldwide forest diversity and dynamics in an era of global change. PMID:25258024

  11. Dispersal of forest insects

    NASA Technical Reports Server (NTRS)

    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.

  12. Forests on thawing permafrost: fragmentation, edge effects, and net forest loss.

    PubMed

    Baltzer, Jennifer L; Veness, Tyler; Chasmer, Laura E; Sniderhan, Anastasia E; Quinton, William L

    2014-03-01

    Much of the world's boreal forest occurs on permafrost (perennially cryotic ground). As such, changes in permafrost conditions have implications for forest function and, within the zone of discontinuous permafrost (30-80% permafrost in areal extent), distribution. Here, forested peat plateaus underlain by permafrost are elevated above the surrounding permafrost-free wetlands; as permafrost thaws, ground surface subsidence leads to waterlogging at forest margins. Within the North American subarctic, recent warming has produced rapid, widespread permafrost thaw and corresponding forest loss. Although permafrost thaw-induced forest loss provides a natural analogue to deforestation occurring in more southerly locations, we know little about how fragmentation relates to subsequent permafrost thaw and forest loss or the role of changing conditions at the edges of forested plateaus. We address these knowledge gaps by (i) examining the relationship of forest loss to the degree of fragmentation in a boreal peatland in the Northwest Territories, Canada; and (ii) quantifying associated biotic and abiotic changes occurring across forest-wetland transitions and extending into the forested plateaus (i.e., edge effects). We demonstrate that the rate of forest loss correlates positively with the degree of fragmentation as quantified by perimeter to area ratio of peat plateaus (edge : area). Changes in depth of seasonal thaw, soil moisture, and effective leaf area index (LAIe ) penetrated the plateau forests by 3-15 m. Water uptake by trees was sevenfold greater in the plateau interior than at the edges with direct implications for tree radial growth. A negative relationship existed between LAIe and soil moisture, suggesting that changes in vegetation physiological function may contribute to changing edge conditions while simultaneously being affected by these changes. Enhancing our understanding of mechanisms contributing to differential rates of permafrost thaw and associated

  13. Sedimentary Records of Hyperpycnal Flows and the Influence of River Damming on Sediment Dynamics of Estuaries: Examples from the Nelson, Churchill, Moisie and Sainte-Marguerite Rivers (Canada)

    NASA Astrophysics Data System (ADS)

    St-Onge, G.; Duboc, Q.; Boyer-Villemaire, U.; Lajeunesse, P.; Bernatchez, P.

    2015-12-01

    Sediment cores were sampled in the estuary of the Nelson and Churchill Rivers in western Hudson Bay, as well as in the estuary of the Moisie and Sainte-Marguerite Rivers in Gulf of St. Lawrence in order to evaluate the impact of hydroelectric dams on the sedimentary regime of these estuaries. The gravity cores at the mouth of the Nelson River recorded several cm-thick rapidly deposited layers with a reverse to normal grading sequence, indicating the occurrence of hyperpycnal flows generated by major floods during the last few centuries. These hyperpycnal flows were probably caused by ice-jam formation, which can increase both the flow and the sediment concentration following the breaching of such natural dams. Following the construction of hydroelectric dams since the 1960s, the regulation of river discharge prevented the formation of hyperpycnal flows, and hence the deposition of hyperpycnites in the upper part of the cores. In the core sampled in the estuary of the Churchill River, only one hyperpycnite was recorded. This lower frequency may be due to the enclosed estuary of the Churchill River, its weaker discharge and the more distal location of the coring site.In the Gulf of St. Lawrence, grain size measurements allowed the identification of a major flood around AD 1844±4 years in box cores from both the Sainte-Marguerite and Moisie Rivers, whereas a drastic decrease in variations in the median grain size occurred around AD ~1900 in the estuary of the Sainte-Marguerite River, highlighting the offshore impact of the SM1 dam construction in the early 1900s. Furthermore, sedimentological variations in the box cores from both estuaries have been investigated by wavelet analysis and the sharp disappearance of high frequencies around AD 1900 in the estuary of the dammed river (Sainte-Marguerite River), but not in the estuary of the natural river (Moisie River), also provides evidence of the influence of dams on the sedimentary regime of estuaries.

  14. Letters in the forest: global precedence effect disappears for letters but not for non-letters under reading-like conditions

    PubMed Central

    Lachmann, Thomas; Schmitt, Andreas; Braet, Wouter; van Leeuwen, Cees

    2014-01-01

    Normally skilled reading involves special processing strategies for letters, which are habitually funneled into an abstract letter code. On the basis of previous studies we argue that this habit leads to the preferred usage of an analytic strategy for the processing of letters, while non-letters are preferably processed via a holistic strategy. The well-known global precedence effect (GPE) seems to contradict to this assumption, since, with compound, hierarchical figures, including letter items, faster responses are observed to the global than to the local level of the figure, as well as an asymmetric interference effect from global to local level. We argue that with letters these effects depend on presentation conditions; only when they elicit the processing strategies automatized for reading, an analytic strategy for letters in contrast to non-letters is to be expected. We compared the GPE for letters and non-letters in central viewing, with the global stimulus size close to the functional visual field in whole word reading (6.5° of visual angle) and local stimuli close to the critical size for fluent reading of individual letters (0.5° of visual angle). Under these conditions, the GPE remained robust for non-letters. For letters, however, it disappeared: letters showed no overall response time advantage for the global level and symmetric congruence effects (local-to-global as well as global-to-local interference). We interpret these results as according to the view that reading is based on resident analytic visual processing strategies for letters. PMID:25101012

  15. Letters in the forest: global precedence effect disappears for letters but not for non-letters under reading-like conditions.

    PubMed

    Lachmann, Thomas; Schmitt, Andreas; Braet, Wouter; van Leeuwen, Cees

    2014-01-01

    Normally skilled reading involves special processing strategies for letters, which are habitually funneled into an abstract letter code. On the basis of previous studies we argue that this habit leads to the preferred usage of an analytic strategy for the processing of letters, while non-letters are preferably processed via a holistic strategy. The well-known global precedence effect (GPE) seems to contradict to this assumption, since, with compound, hierarchical figures, including letter items, faster responses are observed to the global than to the local level of the figure, as well as an asymmetric interference effect from global to local level. We argue that with letters these effects depend on presentation conditions; only when they elicit the processing strategies automatized for reading, an analytic strategy for letters in contrast to non-letters is to be expected. We compared the GPE for letters and non-letters in central viewing, with the global stimulus size close to the functional visual field in whole word reading (6.5° of visual angle) and local stimuli close to the critical size for fluent reading of individual letters (0.5° of visual angle). Under these conditions, the GPE remained robust for non-letters. For letters, however, it disappeared: letters showed no overall response time advantage for the global level and symmetric congruence effects (local-to-global as well as global-to-local interference). We interpret these results as according to the view that reading is based on resident analytic visual processing strategies for letters.

  16. Natural Variability of Mexican Forest Fires

    NASA Astrophysics Data System (ADS)

    Velasco-Herrera, Graciela; Velasco Herrera, Victor Manuel; Kemper-Valverdea, N.

    The purpose of this paper was 1) to present a new algorithm for analyzing the forest fires, 2) to discuss the present understanding of the natural variability at different scales with special emphasis on Mexico conditions since 1972, 3) to analyze the internal and external factors affecting forest fires for example ENSO and Total Solar Irradiance, and 4) to discuss the implications of this knowledge, on research and on restoration and management methods, which purpose is to enhance forest biodiversity conservation. 5) We present an estimate of the Mexican forest fires for the next decade. These results may be useful to minimize human and economic losses.

  17. A tool for assessing ecological status of forest ecosystem

    NASA Astrophysics Data System (ADS)

    Rahman Kassim, Abd; Afizzul Misman, Muhammad; Azahari Faidi, Mohd; Omar, Hamdan

    2016-06-01

    Managers and policy makers are beginning to appreciate the value of ecological monitoring of artificially regenerated forest especially in urban areas. With the advent of more advance technology in precision forestry, high resolution remotely sensed data e.g. hyperspectral and LiDAR are becoming available for rapid and precise assessment of the forest condition. An assessment of ecological status of forest ecosystem was developed and tested using FRIM campus forest stand. The forest consisted of three major blocks; the old growth artificially regenerated native species forests, naturally regenerated forest and recent planted forest for commercial timber and other forest products. Our aim is to assess the ecological status and its proximity to the mature old growth artificially regenerated stand. We used airborne LiDAR, orthophoto and thirty field sampling quadrats of 20x20m for ground verification. The parameter assessments were grouped into four broad categories: a. forest community level-composition, structures, function; landscape structures-road network and forest edges. A metric of parameters and rating criteria was introduced as indicators of the forest ecological status. We applied multi-criteria assessment to categorize the ecological status of the forest stand. The paper demonstrates the application of the assessment approach using FRIM campus forest as its first case study. Its potential application to both artificially and naturally regenerated forest in the variety of Malaysian landscape is discussed

  18. Are there threshold numbers for protected forests?

    PubMed

    Bücking, Winfried

    2003-01-01

    Maintenance of forests biodiversity is intimately related on the one hand to the species and community-related ecological needs of flora and fauna living in the forest and on the other hand the disturbance regimes of the specific forest type. Populations of plants and animals need minimum biotopes for their ontogeny; for assuring their survival they depend on a minimum of connected suitable areas. Specific traits of forest types are based upon different disturbance regimes, ranging from small-scale internal processes (e.g. regeneration, growth, senescence, mortality, gap dynamics) generating normal forest cycles (i.e. regular sequences, e.g. regeneration, optimum, decay phases) to potentially chaotic and large-scale, frequently external, disturbances, e.g. fire, landslides, or beetle attacks. Forest protection may meet the needs of these very different demands by varied protected area networks going from small (>100 ha), medium (1000 ha) to large-scale reserves (National Parks, several thousands of ha). According to this triple protection concept not only graduated threshold numbers, but also threshold sizes and threshold areas for forest protection must be defined. To realize this concept the regional and local conditions (forest area, forest cover percentage, forest composition, socio-economic targets) must always be taken in consideration.

  19. Hydrological recovery in forested landscapes (Invited)

    NASA Astrophysics Data System (ADS)

    Buttle, J. M.

    2013-12-01

    Considerable effort has been expended trying to understand how forest landscapes respond hydrologically to natural (e.g. fire) or anthropogenic (e.g. harvesting) disturbance. However, comparable emphasis has not been placed on assessing whether and how these landscapes recover from such disturbances. Hydrological recovery can be defined as the restoration of hydrologic characteristics (e.g. evapotranspiration rates, soil infiltrability) of disturbed and managed sites to a near pre-disturbance condition. Improved and sustainable use of forest resources depends on better knowledge of the spatial and temporal aspects of recovery of hydrologic properties and processes affected by forest disturbance. This enhanced understanding is particularly pressing given such issues as the implications of climate change for forest ecosystems and the transition of forest management in many regions from forestry for wood, pulp and paper to forest harvesting for biofuels, where the potential magnitude of forest disturbances and hydrological recovery times are largely unknown. Initial studies of hydrological recovery focused on streamflow changes at the basin scale due to forest disturbance and regeneration, while more recent work has examined a variety of hydrologic properties and processes across a range of scales. The differing approaches that are currently used to assess hydrological recovery will be examined, drawing examples of recovery rates of various hydrologic processes in different forest landscapes. Counter-intuitive findings of this research will be highlighted, efforts to incorporate models of hydrological recovery into forest management strategies will be reviewed, and important avenues for future research will be discussed.

  20. Are there threshold numbers for protected forests?

    PubMed

    Bücking, Winfried

    2003-01-01

    Maintenance of forests biodiversity is intimately related on the one hand to the species and community-related ecological needs of flora and fauna living in the forest and on the other hand the disturbance regimes of the specific forest type. Populations of plants and animals need minimum biotopes for their ontogeny; for assuring their survival they depend on a minimum of connected suitable areas. Specific traits of forest types are based upon different disturbance regimes, ranging from small-scale internal processes (e.g. regeneration, growth, senescence, mortality, gap dynamics) generating normal forest cycles (i.e. regular sequences, e.g. regeneration, optimum, decay phases) to potentially chaotic and large-scale, frequently external, disturbances, e.g. fire, landslides, or beetle attacks. Forest protection may meet the needs of these very different demands by varied protected area networks going from small (>100 ha), medium (1000 ha) to large-scale reserves (National Parks, several thousands of ha). According to this triple protection concept not only graduated threshold numbers, but also threshold sizes and threshold areas for forest protection must be defined. To realize this concept the regional and local conditions (forest area, forest cover percentage, forest composition, socio-economic targets) must always be taken in consideration. PMID:12659802

  1. Managed forest reserves: preserving diversity

    USGS Publications Warehouse

    Tappeiner, John; Poage, Nathan; Erickson, Janet L.

    2003-01-01

    Background As part of the Northwest Forest Plan, large areas have been designated on many federal forests in western Oregon to provide critical habitat for plants and animals that are associated with old-growth habitat. Some of the structural characteristics often considered typical of old forests include large-diameter overstory trees, large standing and fallen dead trees, and one or more understory layers (Figure 1). However, not all of these areas are currently in old-growth conditions. Many of them contain young (<40 years), uniformly dense Douglas-fir stands that regenerated after timber harvest. The original management goal for these stands was to produce high yields of timber and associated wood products. With implementation of the Northwest Forest Plan in 1994, the management objective shifted to accelerating development of old-growth characteristics by enhancing structural and biological diversity of these areas. A major challenge today is how to promote these structural characteristics in younger stands. Researchers have been asking if lessons can be learned from the development of our current old growth and applied to management of younger stands. Dr. John Tappeiner and his university and agency research partners are helping to answer this question by examining the differences in development between old-growth and young stands in western Oregon. Understanding how the structure of these old forests developed may provide a model for management of young stands, especially when the management goal is to provide habitat for species associated with older forests.

  2. Forest discrimination with multipolarization imaging radar

    NASA Technical Reports Server (NTRS)

    Ford, J. P.; Wickland, D. E.

    1985-01-01

    The use of radar polarization diversity for discriminating forest canopy variables on airborne synthetic-aperture radar (SAR) images is evaluated. SAR images were acquired at L-Band (24.6 cm) simultaneously in four linear polarization states (HH, HV, VH, and VV) in South Carolina on March 1, 1984. In order to relate the polarization signatures to biophysical properties, false-color composite images were compared to maps of forest stands in the timber compartment. In decreasing order, the most useful correlative forest data are stand basal area, forest age, site condition index, and forest management type. It is found that multipolarization images discriminate variation in tree density and difference in the amount of understory, but do not discriminate between evergreen and deciduous forest types.

  3. TEMPORAL CHANGE IN FRAGMENTATION OF CONTINENTAL US FORESTS

    EPA Science Inventory

    Changes in forest ecosystem function and condition arise from changes in forest fragmentation. Previous studies estimated forest fragmentation for the continental United States (US). In this study, new temporal land-cover data from the National Land Cover Database (NLCD) were us...

  4. Returning forests analyzed with the forest identity

    PubMed Central

    Kauppi, Pekka E.; Ausubel, Jesse H.; Fang, Jingyun; Mather, Alexander S.; Sedjo, Roger A.; Waggoner, Paul E.

    2006-01-01

    Amid widespread reports of deforestation, some nations have nevertheless experienced transitions from deforestation to reforestation. In a causal relationship, the Forest Identity relates the carbon sequestered in forests to the changing variables of national or regional forest area, growing stock density per area, biomass per growing stock volume, and carbon concentration in the biomass. It quantifies the sources of change of a nation's forests. The Identity also logically relates the quantitative impact on forest expanse of shifting timber harvest to regions and plantations where density grows faster. Among 50 nations with extensive forests reported in the Food and Agriculture Organization's comprehensive Global Forest Resources Assessment 2005, no nation where annual per capita gross domestic product exceeded $4,600 had a negative rate of growing stock change. Using the Forest Identity and national data from the Assessment report, a single synoptic chart arrays the 50 nations with coordinates of the rates of change of basic variables, reveals both clusters of nations and outliers, and suggests trends in returning forests and their attributes. The Forest Identity also could serve as a tool for setting forest goals and illuminating how national policies accelerate or retard the forest transitions that are diffusing among nations. PMID:17101996

  5. Forests of opportunities and mischief: disentangling the interactions between forests, parasites and immune responses.

    PubMed

    Renner, Swen C; Lüdtke, Bruntje; Kaiser, Sonja; Kienle, Julia; Schaefer, H Martin; Segelbacher, Gernot; Tschapka, Marco; Santiago-Alarcon, Diego

    2016-08-01

    Habitat characteristics determine the presence of individuals through resource availability, but at the same time, such features also influence the occurrence of parasites. We analyzed how birds respond to changes in interior forest structures, to forest management regimes, and to the risk of haemosporidian infections. We captured and took blood samples from blackcaps (Sylvia atricapilla) and chaffinches (Fringilla coelebs) in three different forest types (beech, mixed deciduous, spruce). We measured birds' body asymmetries, detected avian haemosporidians, and counted white blood cells as an immune measure of each individual per forest type. We used, to our knowledge for the first time, continuous forest structural parameters to quantify habitat structure, and found significant effects of habitat structure on parasite prevalence that previously have been undetected. We found three times higher prevalence for blackcaps compared with chaffinches. Parasite intensity varied significantly within host species depending on forest type, being lowest in beech forests for both host species. Structurally complex habitats with a high degree of entropy had a positive effect on the likelihood of acquiring an infection, but the effect on prevalence was negative for forest sections with a south facing aspect. For blackcaps, forest gaps also had a positive effect on prevalence, but canopy height had a negative one. Our results suggest that forest types and variations in forest structure influence the likelihood of acquiring an infection, which subsequently has an influence on host health status and body condition; however, responses to some environmental factors are host-specific. PMID:27247106

  6. Forests of opportunities and mischief: disentangling the interactions between forests, parasites and immune responses.

    PubMed

    Renner, Swen C; Lüdtke, Bruntje; Kaiser, Sonja; Kienle, Julia; Schaefer, H Martin; Segelbacher, Gernot; Tschapka, Marco; Santiago-Alarcon, Diego

    2016-08-01

    Habitat characteristics determine the presence of individuals through resource availability, but at the same time, such features also influence the occurrence of parasites. We analyzed how birds respond to changes in interior forest structures, to forest management regimes, and to the risk of haemosporidian infections. We captured and took blood samples from blackcaps (Sylvia atricapilla) and chaffinches (Fringilla coelebs) in three different forest types (beech, mixed deciduous, spruce). We measured birds' body asymmetries, detected avian haemosporidians, and counted white blood cells as an immune measure of each individual per forest type. We used, to our knowledge for the first time, continuous forest structural parameters to quantify habitat structure, and found significant effects of habitat structure on parasite prevalence that previously have been undetected. We found three times higher prevalence for blackcaps compared with chaffinches. Parasite intensity varied significantly within host species depending on forest type, being lowest in beech forests for both host species. Structurally complex habitats with a high degree of entropy had a positive effect on the likelihood of acquiring an infection, but the effect on prevalence was negative for forest sections with a south facing aspect. For blackcaps, forest gaps also had a positive effect on prevalence, but canopy height had a negative one. Our results suggest that forest types and variations in forest structure influence the likelihood of acquiring an infection, which subsequently has an influence on host health status and body condition; however, responses to some environmental factors are host-specific.

  7. Forest Health Detectives

    ERIC Educational Resources Information Center

    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. Coupled forest growth-hydrology modelling as an instrument for the assessment of effects of forest management on hydrology in forested catchments

    NASA Astrophysics Data System (ADS)

    Sutmöller, J.; Hentschel, S.; Hansen, J.; Meesenburg, H.

    2011-03-01

    The type and intensity of forest management directly influences regional catchment hydrology. Future forest management must optimise the effects of its practices to achieve sustainable management. With scenario analysis of forestry practices, the effects of different forest utilisation strategies on the hydrology of forested catchments can be temporally and spatially quantified. The approach adopted in this study necessitated the development of an interactive system for the spatially distributed modelling of hydrology in relation to forest stand development. Consequently, a forest growth model was used to simulate stand development assuming various forest management activities. Selected simulated forest growth parameters were entered into the hydrological model to simulate water fluxes under different conditions of forest structure. The approach enables the spatially differentiated quantification of changes in the water regime (e.g. increased evapotranspiration). The results of hydrological simulations in the study area, the Oker catchment (northern Harz Mountains), show that forests contribute to the protection of water systems because they have a balancing effect on the hydrological regime. As scenario simulations also suggest, however, forestry practices can also lead to substantial changes in water budgets of forested catchments. The preservation of the hydrological services of forests requires a sustainable and long-term forest conversion on the basis of current management directives for near natural silviculture. Management strategies on basis of moderate harvesting regimes are preferred because of their limited impact on the water budget.

  9. Focused sunlight factor of forest fire danger assessment using Web-GIS and RS technologies

    NASA Astrophysics Data System (ADS)

    Baranovskiy, Nikolay V.; Sherstnyov, Vladislav S.; Yankovich, Elena P.; Engel, Marina V.; Belov, Vladimir V.

    2016-08-01

    Timiryazevskiy forestry of Tomsk region (Siberia, Russia) is a study area elaborated in current research. Forest fire danger assessment is based on unique technology using probabilistic criterion, statistical data on forest fires, meteorological conditions, forest sites classification and remote sensing data. MODIS products are used for estimating some meteorological conditions and current forest fire situation. Geonformation technologies are used for geospatial analysis of forest fire danger situation on controlled forested territories. GIS-engine provides opportunities to construct electronic maps with different levels of forest fire probability and support raster layer for satellite remote sensing data on current forest fires. Web-interface is used for data loading on specific web-site and for forest fire danger data representation via World Wide Web. Special web-forms provide interface for choosing of relevant input data in order to process the forest fire danger data and assess the forest fire probability.

  10. Forest dynamics.

    PubMed

    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

  11. Forest dynamics

    PubMed Central

    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

  12. Forest dynamics.

    PubMed

    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

  13. Modeling Forest Structure and Vascular Plant Diversity in Piedmont Forests

    NASA Astrophysics Data System (ADS)

    Hakkenberg, C.

    2014-12-01

    When the interacting stressors of climate change and land cover/land use change (LCLUC) overwhelm ecosystem resilience to environmental and climatic variability, forest ecosystems are at increased risk of regime shifts and hyperdynamism in process rates. To meet the growing range of novel biotic and environmental stressors on human-impacted ecosystems, the maintenance of taxonomic diversity and functional redundancy in metacommunities has been proposed as a risk spreading measure ensuring that species critical to landscape ecosystem functioning are available for recruitment as local systems respond to novel conditions. This research is the first in a multi-part study to establish a dynamic, predictive model of the spatio-temporal dynamics of vascular plant diversity in North Carolina Piedmont mixed forests using remotely sensed data inputs. While remote sensing technologies are optimally suited to monitor LCLUC over large areas, direct approaches to the remote measurement of plant diversity remain a challenge. This study tests the efficacy of predicting indices of vascular plant diversity using remotely derived measures of forest structural heterogeneity from aerial LiDAR and high spatial resolution broadband optical imagery in addition to derived topo-environmental variables. Diversity distribution modelling of this sort is predicated upon the idea that environmental filtering of dispersing species help define fine-scale (permeable) environmental envelopes within which biotic structural and compositional factors drive competitive interactions that, in addition to background stochasticity, determine fine-scale alpha diversity. Results reveal that over a range of Piedmont forest communities, increasing structural complexity is positively correlated with measures of plant diversity, though the nature of this relationship varies by environmental conditions and community type. The diversity distribution model is parameterized and cross-validated using three high

  14. Mapping and analyzing Conservation Reserve Program (CRP) enrollment patterns from 1991 to 2011 in Nelson County, North Dakota, using remote sensing and GIS techniques

    NASA Astrophysics Data System (ADS)

    Roehrdanz, Nicholas L.

    Since its inception in 1985, the federally managed Conservation Reserve Program (CRP) has contributed to land-use/land-cover change (LUCC) in areas throughout North Dakota. Concurrently, the Devils Lake Basin and surrounding Prairie Pothole Region (PPR) in North Dakota has experienced pervasive lake and wetland flooding. Unsurprisingly, a clustering of CRP enrollment in certain counties within the basin has occurred, seemingly coinciding with the flooding. Analysis of historical county-level CRP enrollment data pertaining to counties in North Dakota revealed that Nelson County, which is partially within the basin, has developed as a CRP hotspot in the state and has had the greatest increase in the density of CRP acreage amongst the counties in the region. We hypothesize that this high enrollment is the response of farmers losing arable lands and/or field access to the rising waters in the region, thus making CRP enrollment an economically viable option. This study uses Landsat data and GIS analysis to document LUCC and the forces driving it associated with CRP grassland and pervasive lake and wetland flooding in Nelson County. Because CRP field locations are not available from the federal government, we used multi-temporal classification techniques (three scenes per year) to derive land-cover maps from Landsat Thematic Mapper data for five growing seasons (1984, 1991, 1998, 2005, and 2011). We mapped CRP grassland at more than 90% accuracy with validation data derived from interpretation of historical aerial photography and, in the case of 2011, data gathered in the field. LUCC change analysis was done using raster GIS. We found an increase in the amount of CRP grassland in the study area between 1991 (19,688 ha) and 2005 (35,612 ha) and then a decline to 2011 (27,856 ha). Spatial analysis revealed a clustering of CRP in 1991 in the Sheyenne and Goose river valleys, likely attributable to those lands being considered of greater conservation importance. By 1998, a

  15. Silvicultural guidelines for forest stands threatened by the Gypsy moth. Forest Service general technical report (Final)

    SciTech Connect

    Gottschalk, K.W.

    1993-02-02

    The ecological and silvicultural information on the interaction of gypsy moth and its host forest types is incorporated into silvicultural guidelines for minimizing the impacts of gypsy moth on forest stands threatened by the insect. Decision charts are used to match stand and insect conditions to the proper prescription that includes instructions for implementing it.

  16. 78 FR 36163 - Bitterroot National Forest, Darby Ranger District, Como Forest Health Project

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-17

    ..., thermal cover, old growth, and visual quality. DATES: Comments concerning the scope of the analysis must... document and disclose the effects analysis of the proposed Como Forest Health Project (Como FHP). The Como... carried through the analysis because existing conditions in the project area do not meet forest...

  17. Uncertainty in future water supplies from forests: hydrologic effects of a changing forest landscape

    NASA Astrophysics Data System (ADS)

    Jones, J. A.; Achterman, G. L.; Alexander, L. E.; Brooks, K. N.; Creed, I. F.; Ffolliott, P. F.; MacDonald, L.; Wemple, B. C.

    2008-12-01

    Forests account for 33 percent of the U.S. land area, process nearly two-thirds of the fresh water supply, and provide water to 40 percent of all municipalities or about 180 million people. Water supply management is becoming more difficult given the increasing demand for water, climate change, increasing development, changing forest ownership, and increasingly fragmented laws governing forest and watershed management. In 2006, the US National Research Council convened a study on the present understanding of forest hydrology, the hydrologic effects of a changing forest landscape, and research and management needs for sustaining water resources from forested landscapes. The committee concluded that while it is possible to generate short-term water yield increases by timber harvesting, there are a variety of reasons why active forest management has only limited potential to sustainably increase water supplies. These include the short-term nature of the increases in most environments, the timing of the increases, the need for downstream storage, and that continuing ground- based timber harvest can reduce water quality. At the same time, past and continuing changes in forest structure and management may be altering water supplies at the larger time and space scales that are of most interest to forest and water managers. These changes include the legacy of past forest management practices, particularly fire suppression and clearcutting; exurban sprawl, which permanently converts forest land to nonforest uses; effects of climate change on wildfires, insect outbreaks, forest structure, forest species composition, snowpack depth and snowmelt; road networks; and changes in forest land ownership. All of these changes have the potential to alter water quantity and quality from forests. Hence, the baseline conditions that have been used to estimate sustained water yields from forested watersheds may no longer be applicable. Stationarity also can no longer be assumed for the

  18. Forest construction infrastructures for the prevision, suppression, and protection before and after forest fires

    NASA Astrophysics Data System (ADS)

    Drosos, Vasileios C.; Giannoulas, Vasileios J.; Daoutis, Christodoulos

    2014-08-01

    Climatic changes cause temperature rise and thus increase the risk of forest fires. In Greece the forests with the greatest risk to fire are usually those located near residential and tourist areas where there are major pressures on land use changes, while there are no currently guaranteed cadastral maps and defined title deeds because of the lack of National and Forest Cadastre. In these areas the deliberate causes of forest fires are at a percentage more than 50%. This study focuses on the forest opening up model concerning both the prevention and suppression of forest fires. The most urgent interventions that can be done after the fire destructions is also studied in relation to soil protection constructions, in order to minimize the erosion and the torrential conditions. Digital orthophotos were used in order to produce and analyze spatial data using Geographical Information Systems (GIS). Initially, Digital Elevation Models were generated, based on photogrammetry and forest areas as well as the forest road network were mapped. Road density, road distance, skidding distance and the opening up percentage were accurately measured for a forest complex. Finally, conclusions and suggestions have been drawn about the environmental compatibility of forest protection and wood harvesting works. In particular the contribution of modern technologies such as digital photogrammetry, remote sensing and Geographical Information Systems is very important, allowing reliable, effective and fast process of spatial analysis contributing to a successful planning of opening up works and fire protection.

  19. Sustainable Forest Bioenergy Initiative

    SciTech Connect

    Breger, Dwayne; Rizzo, Rob

    2011-09-20

    project due to changing public policy demands brought forth in the course of the public discourse on this topic. We found that some tasks needed to be adjusted to meet changed conditions. Shortly after the start of SFBI, DOER recognized that establishing demonstration plots within state owned lands was not possible as the state enacted a temporary freeze on all timber harvesting on state lands, to allow for the completion of an assessment of current impacts of this activity and time to develop prudent policies on land conservation. Even more significantly, the state’s energy and environmental Secretary asked DOER to place a “sustainability” criterion for biomass in the RPS regulations, and the passage of the landmark Global Warming Solutions Act in 2008 committed DOER to very carefully consider and assure that biomass energy supported by the RPS met carbon reduction thresholds aligned with the state’s reduction commitments. These needs led to some adjustment of the SFBI scope and objectives to meet the policy challenges. Most notably was the funding and commissioning of the report by the Manomet Center for Conservation Sciences which provided the sustainability and carbon impact framework necessary for DOER to move policy forward prudently. The “Manomet Study” has moved this emerging policy issue substantially forward, gained national and international significance, and provided a new look at how the forest sequesters carbon and the effect of the removal of growing stock for energy on future carbon sequestration and atmospheric flux. This activity provided information that supports the objectives of SFBI but to accommodate this work, several subtasks were combined and addressed within the framework of the Manomet research study. The expected outcomes of the SFBI include the development of biomass energy systems that support sustainable forest management, new investment in forestry and fuel supply infrastructure, biomass energy generation that contributes to

  20. Size reduction of an ACTH-secreting pituitary macroadenoma in Nelson's syndrome by sodium valproate: effect of withdrawal and re-institution of treatment.

    PubMed

    Loli, P; Berselli, M E; Vignati, F; De Grandi, C; Tagliaferri, M

    1988-11-01

    We describe herein the reduction in the size of an ACTH-secreting pituitary macroadenoma in a patient with Nelson's syndrome during chronic administration of sodium valproate, and the changes in tumour volume after withdrawal and re-institution of treatment. The patient had elevated plasma ACTH levels (1123-1255 pmol/l), which increased markedly after CRH stimulation. A first 4-month course of sodium valproate administration (600 mg/day, orally) was started. Plasma ACTH fell to 550-726 pmol/l with persistence of responsiveness to CRH; brain computed tomography showed a clearcut reduction of tumour size. One month after drug withdrawal, the tumour volume appeared unchanged and plasma ACTH values ranged between 374 and 440 pmol/l. One and a half year after drug withdrawal, a brain computed tomography showed re-expansion of the pituitary adenoma with evidence of suprasellar extension, which had never been seen previously. Plasma ACTH ranged between 113 and 199 pmol/l. A second course of sodium valproate was started; after three months, a brain computed tomography documented clearcut reduction of tumour volume from a suprasellar extension to a partially empty pituitary fossa. Plasma ACTH ranged from 396 to 542 pmol/l with persistence of responsiveness to CRH. The present report documents for the first time the reduction of tumour size in a patient with an ACTH-secreting macroadenoma by chronic administration of sodium valproate.

  1. Northern Forest Ecosystem Dynamics Using Coupled Models and Remote Sensing

    NASA Technical Reports Server (NTRS)

    Ranson, K. J.; Sun, G.; Knox, R. G.; Levine, E. R.; Weishampel, J. F.; Fifer, S. T.

    1999-01-01

    Forest ecosystem dynamics modeling, remote sensing data analysis, and a geographical information system (GIS) were used together to determine the possible growth and development of a northern forest in Maine, USA. Field measurements and airborne synthetic aperture radar (SAR) data were used to produce maps of forest cover type and above ground biomass. These forest attribute maps, along with a conventional soils map, were used to identify the initial conditions for forest ecosystem model simulations. Using this information along with ecosystem model results enabled the development of predictive maps of forest development. The results obtained were consistent with observed forest conditions and expected successional trajectories. The study demonstrated that ecosystem models might be used in a spatial context when parameterized and used with georeferenced data sets.

  2. Comparing current and desired ecological conditions at a landscape scale in the Cumberland Plateau and Mountains, USA.

    SciTech Connect

    Druckenbrod, Dr. Daniel L.; Dale, Virginia H; Olsen, Lisa M

    2007-01-01

    We applied a landscape conservation approach that quantifies current and desired ecological conditions for 10680 km2 of diverse forests in the Cumberland Plateau and Mountains of Tennessee and Kentucky. In this case study, forest cover was classified using Landsat TM imagery and evaluated with forest inventory data. Landform forest associations were characterized by combining forest cover, physiographic descriptions of remnant and historical forests, and forest structure and composition from the inventory data. These landform forest associations estimate current forest conditions and, in comparison with a projection of potential natural forest conditions, indicated that upland deciduous forests in the Plateau have the greatest reduction in cover, particularly in small private ownerships. Although of similar composition, upland deciduous forests in the Plateau also possessed younger stands with smaller trees than observed from potential old-growth conditions. These results provide scientific guidance for transitioning these forests toward desired ecological conditions through regional conservation initiatives.

  3. Temporal change in fragmentation of continental US forests

    USGS Publications Warehouse

    Wickham, J.D.; Riitters, K.H.; Wade, T.G.; Homer, C.

    2008-01-01

    Changes in forest ecosystem function and condition arise from changes in forest fragmentation. Previous studies estimated forest fragmentation for the continental United States (US). In this study, new temporal land-cover data from the National Land Cover Database (NLCD) were used to estimate changes in forest fragmentation at multiple scales for the continental US. Early and late dates for the land-cover change data were ca. 1992 and ca. 2001. Forest density was used as a multi-scale index of fragmentation by measuring the proportion of forest in neighborhoods ranging in size from 2.25 to 5314.41 ha. The multi-scale forest density maps were classified using thresholds of 40% (patch), 60% (dominant), and 90% (interior) to analyze temporal change of fragmentation. The loss of dominant and interior forest showed distinct scale effects, whereas loss of patch forest was much less scale-dependent. Dominant forest loss doubled from the smallest to the largest spatial scale, while interior forest loss increased by approximately 80% from the smallest to the second largest spatial scale, then decreased somewhat. At the largest spatial scale, losses of dominant and interior forest were 5 and 10%, respectively, of their ca. 1992 amounts. In contrast, patch forest loss increased by only 25% from the smallest to largest spatial scale. These results indicate that continental US forests were sensitive to forest loss because of their already fragmented state. Forest loss would have had to occur in an unlikely spatial pattern in order to avoid the proportionately greater impact on dominant and interior forest at larger spatial scales. ?? 2008 US Government.

  4. Mexican forest fires and their decadal variations

    NASA Astrophysics Data System (ADS)

    Velasco Herrera, Graciela

    2016-11-01

    A high forest fire season of two to three years is regularly observed each decade in Mexican forests. This seems to be related to the presence of the El Niño phenomenon and to the amount of total solar irradiance. In this study, the results of a multi-cross wavelet analysis are reported based on the occurrence of Mexican forest fires, El Niño and the total solar irradiance for the period 1970-2014. The analysis shows that Mexican forest fires and the strongest El Niño phenomena occur mostly around the minima of the solar cycle. This suggests that the total solar irradiance minima provide the appropriate climatological conditions for the occurrence of these forest fires. The next high season for Mexican forest fires could start in the next solar minimum, which will take place between the years 2017 and 2019. A complementary space analysis based on MODIS active fire data for Mexican forest fires from 2005 to 2014 shows that most of these fires occur in cedar and pine forests, on savannas and pasturelands, and in the central jungles of the Atlantic and Pacific coasts.

  5. Education Highlights: Forest Biomass

    ScienceCinema

    Barone, Rachel; Canter, Christina

    2016-07-12

    Argonne intern Rachel Barone from Ithaca College worked with Argonne mentor Christina Canter in studying forest biomass. This research will help scientists develop large scale use of biofuels from forest biomass.

  6. Chisholm Forest Fire

    Atmospheric Science Data Center

    2013-04-17

    ... Larger Image A new look at smoke from the Chisholm forest fire, which ignited on May 23, 2001 about 160 kilometers north of ... stratosphere. Scientists have postulated a link between fires in northern forests and the observed enhancements in stratospheric ...

  7. Natural VOC emissions from forests in Poland

    NASA Astrophysics Data System (ADS)

    Isidorov, V.; Jaroszynska, J.; Sacharewicz, T.; Piroznikow, E.

    On the basis of the last inventory of forests and climatic conditions in Poland, a national evaluation of the emissions of reactive volatile organic compounds (VOCs) was carried out. Calculations took into account the composition and age structure of forests as well as the temperature dependencies of VOC emission rate for the main European forest-forming tree species. In the case of isoprene, the dependence on illumination level and day length was also taken into account. Estimations were made for all 49 administrative regions of Poland. Depending on weather conditions in different years, the total VOC emission of Polish forests can be in the range 186-763 kt yr -1. For instance, for a moderately warm year, 1992, it was estimated at 440.6 kt, which represents 25% of the total VOC emissions in Poland.

  8. Effects of forest management on carbon and energy exchange of beech forests

    NASA Astrophysics Data System (ADS)

    Herbst, Mathias; Mund, Martina; Knohl, Alexander

    2014-05-01

    Atmospheric carbon and energy fluxes of a managed beech forest are compared with those of a nearby unmanaged, old-growth beech forest in central Germany. Both forests are located at similar altitude and they face similar meteorological conditions. They are also similar with respect to canopy height (37 m) and mean tree age (120 years). The managed forest is a monospecific, even-aged stand with species-rich ground vegetation and a leaf area index of about 4, whereas the old stand is clearly beech-dominated but interspersed with ash and sycamore trees. It has a multi-layer canopy made up of trees of various ages and its leaf area index is about 5. The comparison is based on 23 site-years of eddy covariance measurements of carbon and energy fluxes and on regular biomass measurements in terms of dendrometry and litter collection. On average the two forests did not differ significantly in annual net carbon uptake derived from eddy covariance data (508 and 483 g C m-2a-1 for the managed and the unmanaged forest, respectively), however the managed forest showed a much larger interannual variability in gross primary production than the unmanaged forest did. This trend agreed well with independent dendrometric measurements of net ecosystem production from both forests. In contrast, ecosystem respiration did neither vary significantly between the two forests nor between different years. The total annual evapotranspiration was higher at the unmanaged forest site (549 mm a-1 compared to 504 mm a-1 at the managed site), which was probably due to a higher interception loss from the denser canopy in the unmanaged forest. We discuss whether the conclusion can be drawn from this case study that common forest management activities improve the water use efficiency of European beech forests but make them more vulnerable, in terms of carbon uptake, against extreme meteorological conditions such as, for example, summer heat waves or late frosts in springtime. Regardless of this

  9. The Children's Rain Forest.

    ERIC Educational Resources Information Center

    Thornton, Carol A.; And Others

    1995-01-01

    Describes a unit on rain forests in which first graders studied about rain forests, built a classroom rain forest, and created a bulletin board. They also graphed rainfall, estimated body water, and estimated the number of newspapers that could be produced from one canopy tree. (MKR)

  10. Participatory Forest Management in Ethiopia: Learning from Pilot Projects

    NASA Astrophysics Data System (ADS)

    Ameha, Aklilu; Larsen, H. O.; Lemenih, Mulugeta

    2014-04-01

    Different arrangements of decentralized forest management have been promoted as alternatives to centralized and top down approaches to halt tropical deforestation and forest degradation. Ethiopia is one of the countries piloting one of these approaches. To inform future programs and projects it is essential to learn from existing pilots and experiences. This paper analyses five of the pilot participatory forest management (PFM) programs undertaken in Ethiopia. The study is based on the Forest User Group (FUG) members' analyses of the programs using selected outcome variables: forest income, change in forest conditions, forest ownership feelings and effectiveness of FUGs as forest managing institutions. These variables were assessed at three points in time—before the introduction of PFM, during the project implementation and after the projects ended. Data were collected using group discussions, key informant interviews and transect walks through the PFM forests. The results show that in all of the five cases the state of the forest is perceived to have improved with the introduction of PFM, and in four of the cases the improvement was maintained after projects ended. Regulated access to the forests following introduction of PFM was not perceived to have affected forest income negatively. There are, however, serious concerns about the institutional effectiveness of the FUGs after projects ended, and this may affect the success of the PFM approach in the longer term.

  11. MODIS Based Estimation of Forest Aboveground Biomass in China

    PubMed Central

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

    2015-01-01

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

  12. Forecasting method of nationak-level forest fire risk rating

    NASA Astrophysics Data System (ADS)

    Qin, Xian-lin; Zhang, Zi-hui; Li, Zeng-yuan; Yi, Hao-ruo

    2008-11-01

    The risk level of forest fire not only depends on weather, topography, human activities, socio-economic conditions, but is also closely related to the types, growth, moisture content, and quantity of forest fuel on the ground. How to timely acquire information about the growth and moisture content of forest fuel and climate for the whole country is critical to national-level forest fire risk forecasting. The development and application of remote sensing (RS), geographic information system (GIS), databases, internet, and other modern information technologies has provided important technical means for macro-regional forest fire risk forecasting. In this paper, quantified forecasting of national-level forest fire risk was studied using Fuel State Index (FSI) and Background Composite Index (BCI). The FSI was estimated using Moderate Resolution Imaging Spectroradiaometer (MODIS) data. National meteorological data and other basic data on distribution of fuel types and forest fire risk rating were standardized in ArcGIS platform to calculate BCI. The FSI and the BCI were used to calculate the Forest Fire Danger Index (FFDI), which is regarded as a quantitative indicator for national forest fire risk forecasting and forest fire risk rating, shifting from qualitative description to quantitative estimation. The major forest fires occurred in recent years were taken as examples to validate the above method, and results indicated that the method can be used for quantitative forecasting of national-level forest fire risks.

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

    PubMed

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

    2015-01-01

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

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

    PubMed

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

    2015-01-01

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

  15. Adaptive forest management for drinking water protection under climate change

    NASA Astrophysics Data System (ADS)

    Koeck, R.; Hochbichler, E.

    2012-04-01

    Drinking water resources drawn from forested catchment areas are prominent for providing water supply on our planet. Despite the fact that source waters stemming from forested watersheds have generally lower water quality problems than those stemming from agriculturally used watersheds, it has to be guaranteed that the forest stands meet high standards regarding their water protection functionality. For fulfilling these, forest management concepts have to be applied, which are adaptive regarding the specific forest site conditions and also regarding climate change scenarios. In the past century forest management in the alpine area of Austria was mainly based on the cultivation of Norway spruce, by the way neglecting specific forest site conditions, what caused in many cases highly vulnerable mono-species forest stands. The GIS based forest hydrotope model (FoHyM) provides a framework for forest management, which defines the most crucial parameters in a spatial explicit form. FoHyM stratifies the spacious drinking water protection catchments into forest hydrotopes, being operational units for forest management. The primary information layer of FoHyM is the potential natural forest community, which reflects the specific forest site conditions regarding geology, soil types, elevation above sea level, exposition and inclination adequately and hence defines the specific forest hydrotopes. For each forest hydrotope, the adequate tree species composition and forest stand structure for drinking water protection functionality was deduced, based on the plant-sociological information base provided by FoHyM. The most important overall purpose for the related elaboration of adaptive forest management concepts and measures was the improvement of forest stand stability, which can be seen as the crucial parameter for drinking water protection. Only stable forest stands can protect the fragile soil and humus layers and hence prevent erosion process which could endanger the water

  16. A macroecological analysis of SERA derived forest heights and implications for forest volume remote sensing.

    PubMed

    Brolly, Matthew; Woodhouse, Iain H; Niklas, Karl J; Hammond, Sean T

    2012-01-01

    Individual trees have been shown to exhibit strong relationships between DBH, height and volume. Often such studies are cited as justification for forest volume or standing biomass estimation through remote sensing. With resolution of common satellite remote sensing systems generally too low to resolve individuals, and a need for larger coverage, these systems rely on descriptive heights, which account for tree collections in forests. For remote sensing and allometric applications, this height is not entirely understood in terms of its location. Here, a forest growth model (SERA) analyzes forest canopy height relationships with forest wood volume. Maximum height, mean, H₁₀₀, and Lorey's height are examined for variability under plant number density, resource and species. Our findings, shown to be allometrically consistent with empirical measurements for forested communities world-wide, are analyzed for implications to forest remote sensing techniques such as LiDAR and RADAR. Traditional forestry measures of maximum height, and to a lesser extent H₁₀₀ and Lorey's, exhibit little consistent correlation with forest volume across modeled conditions. The implication is that using forest height to infer volume or biomass from remote sensing requires species and community behavioral information to infer accurate estimates using height alone. SERA predicts mean height to provide the most consistent relationship with volume of the height classifications studied and overall across forest variations. This prediction agrees with empirical data collected from conifer and angiosperm forests with plant densities ranging between 10²-10⁶ plants/hectare and heights 6-49 m. Height classifications investigated are potentially linked to radar scattering centers with implications for allometry. These findings may be used to advance forest biomass estimation accuracy through remote sensing. Furthermore, Lorey's height with its specific relationship to remote sensing

  17. A Macroecological Analysis of SERA Derived Forest Heights and Implications for Forest Volume Remote Sensing

    PubMed Central

    Brolly, Matthew; Woodhouse, Iain H.; Niklas, Karl J.; Hammond, Sean T.

    2012-01-01

    Individual trees have been shown to exhibit strong relationships between DBH, height and volume. Often such studies are cited as justification for forest volume or standing biomass estimation through remote sensing. With resolution of common satellite remote sensing systems generally too low to resolve individuals, and a need for larger coverage, these systems rely on descriptive heights, which account for tree collections in forests. For remote sensing and allometric applications, this height is not entirely understood in terms of its location. Here, a forest growth model (SERA) analyzes forest canopy height relationships with forest wood volume. Maximum height, mean, H100, and Lorey's height are examined for variability under plant number density, resource and species. Our findings, shown to be allometrically consistent with empirical measurements for forested communities world-wide, are analyzed for implications to forest remote sensing techniques such as LiDAR and RADAR. Traditional forestry measures of maximum height, and to a lesser extent H100 and Lorey's, exhibit little consistent correlation with forest volume across modeled conditions. The implication is that using forest height to infer volume or biomass from remote sensing requires species and community behavioral information to infer accurate estimates using height alone. SERA predicts mean height to provide the most consistent relationship with volume of the height classifications studied and overall across forest variations. This prediction agrees with empirical data collected from conifer and angiosperm forests with plant densities ranging between 102–106 plants/hectare and heights 6–49 m. Height classifications investigated are potentially linked to radar scattering centers with implications for allometry. These findings may be used to advance forest biomass estimation accuracy through remote sensing. Furthermore, Lorey's height with its specific relationship to remote sensing physics is

  18. Different Climate - Fire Relationships on Forested and Non-Forested Landscapes in California

    NASA Astrophysics Data System (ADS)

    Keeley, J. E.

    2013-12-01

    Wildfire activity has increased in western USA forests and climate change is considered a driving factor. Previous studies have shown that over the past several decades forest fires have increased significantly on forested landscapes and is correlated with warmer and drier conditions. However, the bulk of the landscape in the western US comprises non-forested ecosystems and there are no reports on trends in fire activity for these landscapes. Here we show that in the highly fire-prone Sierra Nevada region of California increased fired activity over the last 50 years has only occurred in the higher-elevation forests, and is not characteristic of the lower elevation grasslands, woodlands and shrublands. In our study, forests exhibited increased fire activity in years with warmer and drier springs, both in the early twentieth century as well as more recently. On lower elevation non-forested landscapes warmer and drier conditions were not related to fire activity over the course of the last 90 years of record. These patterns predict that climate changes including higher spring temperatures and lower spring precipitation, will have a significant impact on future fire regimes only in higher elevation forested ecosystems. Future fire regimes in the lower more densely populated landscapes are likely to be more affected by global changes that directly involve land use patterns and less on climate.

  19. Analysis of zone of vulnurability and impact of forest fires in forest ecosystems in north algeria by susing remote sensing

    NASA Astrophysics Data System (ADS)

    Zegrar, Ahmed

    2010-05-01

    The Forest in steppe present ecological diversity, and seen climatic unfavourable conditions in zone and impact of forest fires; we notes deterioration of physical environment particularly, deterioration of natural forest. This deterioration of forests provokes an unbalance of environment witch provokes a process of deterioration advanced in the ultimate stadium is desertification. By elsewhere, where climatic conditions are favourable, the fire is an ecological and acted agent like integral part of evolution of the ecosystems, the specific regeneration of plants are influenced greatly by the regime of fire (season of fire, intensity, interval), witch leads to the recuperation of the vegetation of meadow- fire. In this survey we used the pictures ALSAT-1 for detection of zones with risk of forest fire and their impact on the naturals forests in region named TLEMCEN in the north west of Algeria. A thematic detailed analysis of forests well attended ecosystems some processing on the picture ALSAT-1, we allowed to identify and classifying the forests in there opinion components flowers. We identified ampleness of fire on this zone also. Some parameters as the slope, the proximity to the road and the forests formations were studied in the goal of determining the zones to risk of forest fire. A crossing of diaper of information in a GIS according to a very determined logic allowed classifying the zones in degree of risk of fire in semi arid zone witch forest zone not encouraging the regeneration but permitting the installation of cash of steppe which encourages the desertification.

  20. Conceptualizing Forest Degradation.

    PubMed

    Ghazoul, Jaboury; Burivalova, Zuzana; Garcia-Ulloa, John; King, Lisa A

    2015-10-01

    Forest degradation is a global environmental issue, but its definition is problematic. Difficulties include choosing appropriate reference states, timescales, thresholds, and forest values. We dispense with many such ambiguities by interpreting forest degradation through the frame of ecological resilience, and with reference to forest dynamics. Specifically, we define forest degradation as a state of anthropogenically induced arrested succession, where ecological processes that underlie forest dynamics are diminished or severely constrained. Metrics of degradation might include those that reflect ecological processes shaping community dynamics, notably the regeneration of plant species. Arrested succession implies that management intervention is necessary to recover successional trajectories. Such a definition can be applied to any forest ecosystem, and can also be extended to other ecosystems. PMID:26411619

  1. The empty forest revisited.

    PubMed

    Wilkie, David S; Bennett, Elizabeth L; Peres, Carlos A; Cunningham, Andrew A

    2011-03-01

    Tropical forests are among the most species-rich ecosystems on the planet. Some authors argue that predictions of a tropical forest extinction crisis based on analyses of deforestation rates are overly pessimistic since they do not take account of future agricultural abandonment as a result of rural-urban migration and subsequent secondary regrowth. Even if such regrowth occurs, it is crucial to consider threats to species that are not directly correlated with area of forest cover. Hunting is an insidious but significant driver of tropical forest defaunation, risking cascading changes in forest plant and animal composition. Ineffective legislation and enforcement along with a failure of decision makers to address the threats of hunting is fanning the fire of a tropical forest extinction crisis. If tropical forest ecosystems are to survive, the threat of unsustainable hunting must be adequately addressed now.

  2. The empty forest revisited.

    PubMed

    Wilkie, David S; Bennett, Elizabeth L; Peres, Carlos A; Cunningham, Andrew A

    2011-03-01

    Tropical forests are among the most species-rich ecosystems on the planet. Some authors argue that predictions of a tropical forest extinction crisis based on analyses of deforestation rates are overly pessimistic since they do not take account of future agricultural abandonment as a result of rural-urban migration and subsequent secondary regrowth. Even if such regrowth occurs, it is crucial to consider threats to species that are not directly correlated with area of forest cover. Hunting is an insidious but significant driver of tropical forest defaunation, risking cascading changes in forest plant and animal composition. Ineffective legislation and enforcement along with a failure of decision makers to address the threats of hunting is fanning the fire of a tropical forest extinction crisis. If tropical forest ecosystems are to survive, the threat of unsustainable hunting must be adequately addressed now. PMID:21449969

  3. A Novel Tropical Dry Forests: A Response to Environmental Change.

    NASA Astrophysics Data System (ADS)

    Lugo, A. E.; Molina, S.

    2015-12-01

    Dry Forest environments are favorable to human settlement and activities, leading to deforestation, agricultural enterprises, land degradation, and abandonment. As a result, tropical dry forests are vulnerable and experience a high rate of cover loss, which often requires restoration activities. We have studied the natural regeneration of dry forests in Puerto Rico following a variety of human activities including farming, cattle pasturing, charcoal production, and human dwellings. Our results show a high level of forest resilience to anthropogenic disturbances but also a change of species composition relative to undisturbed native forests. This novelty of forest composition represents a natural response to environmental changes induced by human activity and pre-adapts forests to conditions in the Anthropocene.

  4. The role of stand history in assessing forest impacts

    USGS Publications Warehouse

    Dale, V.H.; Doyle, T.W.

    1987-01-01

    Air pollution, harvesting practices, and natural disturbances can affect the growth of trees and forest development. To make predictions about anthropogenic impacts on forests, we need to understand how these factors affect tree growth. In this study the effect of disturbance history on tree growth and stand structure was examined by using a computer model of forest development. The model was run under the climatic conditions of east Tennessee, USA, and the results compared to stand structure and tree growth data from a yellow poplar-white oak forest. Basal area growth and forest biomass were more accurately projected when rough approximations of the thinning and fire history typical of the measured plots were included in the simulation model. Stand history can influence tree growth rates and forest structure and should be included in any attempt to assess forest impacts.

  5. Change in avian abundance predicted from regional forest inventory data

    USGS Publications Warehouse

    Twedt, Daniel J.; Tirpak, John M.; Jones-Farrand, D. Todd; Thompson, Frank R.; Uihlein, William B.; Fitzgerald, Jane A.

    2010-01-01

    An inability to predict population response to future habitat projections is a shortcoming in bird conservation planning. We sought to predict avian response to projections of future forest conditions that were developed from nationwide forest surveys within the Forest Inventory and Analysis (FIA) program. To accomplish this, we evaluated the historical relationship between silvicolous bird populations and FIA-derived forest conditions within 25 ecoregions that comprise the southeastern United States. We aggregated forest area by forest ownership, forest type, and tree size-class categories in county-based ecoregions for 5 time periods spanning 1963-2008. We assessed the relationship of forest data with contemporaneous indices of abundance for 24 silvicolous bird species that were obtained from Breeding Bird Surveys. Relationships between bird abundance and forest inventory data for 18 species were deemed sufficient as predictive models. We used these empirically derived relationships between regional forest conditions and bird populations to predict relative changes in abundance of these species within ecoregions that are anticipated to coincide with projected changes in forest variables through 2040. Predicted abundances of these 18 species are expected to remain relatively stable in over a quarter (27%) of the ecoregions. However, change in forest area and redistribution of forest types will likely result in changed abundance of some species within many ecosystems. For example, abundances of 11 species, including pine warbler (Dendroica pinus), brown-headed nuthatch (Sitta pusilla), and chuckwills- widow (Caprimulgus carolinensis), are projected to increase within more ecoregions than ecoregions where they will decrease. For 6 other species, such as blue-winged warbler (Vermivora pinus), Carolina wren (Thryothorus ludovicianus), and indigo bunting (Passerina cyanea), we projected abundances will decrease within more ecoregions than ecoregions where they will

  6. Relationships between net primary productivity and forest stand age in U.S. forests

    NASA Astrophysics Data System (ADS)

    He, Liming; Chen, Jing M.; Pan, Yude; Birdsey, Richard; Kattge, Jens

    2012-09-01

    Net primary productivity (NPP) is a key flux in the terrestrial ecosystem carbon balance, as it summarizes the autotrophic input into the system. Forest NPP varies predictably with stand age, and quantitative information on the NPP-age relationship for different regions and forest types is therefore fundamentally important for forest carbon cycle modeling. We used four terms to calculate NPP: annual accumulation of live biomass, annual mortality of aboveground and belowground biomass, foliage turnover to soil, and fine root turnover in soil. For U.S. forests the first two terms can be reliably estimated from the Forest Inventory and Analysis (FIA) data. Although the last two terms make up more than 50% of total NPP, direct estimates of these fluxes are highly uncertain due to limited availability of empirical relationships between aboveground biomass and foliage or fine root biomass. To resolve this problem, we developed a new approach using maps of leaf area index (LAI) and forest age at 1 km resolution to derive LAI-age relationships for 18 major forest type groups in the USA. These relationships were then used to derive foliage turnover estimates using species-specific trait data for leaf specific area and longevity. These turnover estimates were also used to derive the fine root turnover based on reliable relationships between fine root and foliage turnover. This combination of FIA data, remote sensing, and plant trait information allows for the first empirical and reliable NPP-age relationships for different forest types in the USA. The relationships show a general temporal pattern of rapid increase in NPP in the young ages of forest type groups, peak growth in the middle ages, and slow decline in the mature ages. The predicted patterns are influenced by climate conditions and can be affected by forest management. These relationships were further generalized to three major forest biomes for use by continental-scale carbon cycle models in conjunction with

  7. Protection against fire in the mountainous forests of Greece case study: forest complex of W. Nestos

    NASA Astrophysics Data System (ADS)

    Drosos, Vasileios C.; Giannoulas, Vasileios J.; Stergiadou, Anastasia; Karagiannis, Evaggelos; Doukas, Aristotelis-Kosmas G.

    2014-08-01

    Forest fires are an ancient phenomenon. Appear, however, with devastating frequency and intensity over the last 30 years. In our country, the climatic conditions in combination with the intense relief, favor their rapid spread. Considering the fact that environmental conditions provided for decades even worse (increased temperature, drought and vegetation), then the problem of forest fires in our country, is expected to become more intense. The work focuses on the optimization model of the opening up of the forest mountain areas taking into account the prevention and suppression of forest fires. Research area is the mountain forest complex of W. Nestos of Drama Prefecture. The percentage of forest protection area is examined under the light whether the total hose length corresponds to the actual operational capacity to reach a fire source. For this reason are decided to present a three case study concerning area of the forest being protected by fire extinguishing vehicles. The first one corresponds to a fire suppression bandwidth (buffer zone) with a capacity radius of 150m uphill and 250m downhill from the origin point where the fire extinguishing vehicle stands. The second one corresponds to a fire suppression capacity of 200m uphill and 400m downhill and the third one corresponds to a fire suppression capacity of 300m uphill and 500m downhill. The most important forest technical infrastructures to prevent fire are roads network (opening up) for fire protection and buffer zones. Patrols of small and agile 4 × 4 appropriately equipped (pipe length of 500 meters and putting pressure on uphill to 300 meters) for the first attack of the fire in the summer months coupled with early warning of fire observatories adequately cover the forest protection of W. Nestos complex. But spatial distribution needed improvements to a road density of the optimum economic Dec, both forest protection and for better management (skidding) of woody capital.

  8. Historical forest patterns of Oregon's central Coast Range

    USGS Publications Warehouse

    Ripple, W.J.; Hershey, K.T.; Anthony, R.G.

    2000-01-01

    To describe the composition and pattern of unmanaged forestland in Oregon's central Coast Range, we analyzed forest conditions from a random sample of 18 prelogging (1949 and earlier) landscapes. We also compared the amount and variability of old forest (conifer-dominated stands > 53 cm dbh) in the prelogging landscapes with that in the current landscapes. Sixty-three percent of the prelogging landscape comprised old forest, approximately 21% of which also had a significant (> 20% cover) hardwood component. The proportions of forest types across the 18 prelogging landscapes varied greatly for both early seral stages (cv = 81194) and hardwoods (cv = 127) and moderately for old forest (cv = 39). With increasing distance from streams, the amount of hardwoods and nonforest decreased, whereas the amount of seedling/sapling/pole and young conifers increased. The amount of old forest was significantly greater (p < 0.002) in prelogging forests than in current landscapes. Old-forest patterns also differed significantly (p < 0.015) between prelogging and current landscapes; patch density, coefficient of variation of patch size, edge density, and fragmentation were greater in current landscapes and mean patch size, largest patch size, and core habitat were greater in prelogging forests. Generally, old-forest landscape pattern variables showed a greater range in prelogging landscapes than in current landscapes. Management strategies designed to increase the amount of old forest and the range in landscape patterns would result in a landscape more closely resembling that found prior to intensive logging. (C) 2000 Elsevier Science Ltd.

  9. Effectiveness of community forestry in Prey Long forest, Cambodia.

    PubMed

    Lambrick, Frances H; Brown, Nick D; Lawrence, Anna; Bebber, Daniel P

    2014-04-01

    Cambodia has 57% forest cover, the second highest in the Greater Mekong region, and a high deforestation rate (1.2%/year, 2005-2010). Community forestry (CF) has been proposed as a way to reduce deforestation and support livelihoods through local management of forests. CF is expanding rapidly in Cambodia. The National Forests Program aims to designate one million hectares of forest to CF by 2030. However, the effectiveness of CF in conservation is not clear due to a global lack of controlled comparisons, multiple meanings of CF, and the context-specific nature of CF implementation. We assessed the effectiveness of CF by comparing 9 CF sites with paired controls in state production forest in the area of Prey Long forest, Cambodia. We assessed forest condition in 18-20 randomly placed variable-radius plots and fixed-area regeneration plots. We surveyed 10% of households in each of the 9 CF villages to determine the proportion that used forest products, as a measure of household dependence on the forest. CF sites had fewer signs of anthropogenic damage (cut stems, stumps, and burned trees), higher aboveground biomass, more regenerating stems, and reduced canopy openness than control areas. Abundance of economically valuable species, however, was higher in control sites. We used survey results and geographic parameters to model factors affecting CF outcomes. Interaction between management type, CF or control, and forest dependence indicated that CF was more effective in cases where the community relied on forest products for subsistence use and income. PMID:24400672

  10. Effectiveness of community forestry in Prey Long forest, Cambodia.

    PubMed

    Lambrick, Frances H; Brown, Nick D; Lawrence, Anna; Bebber, Daniel P

    2014-04-01

    Cambodia has 57% forest cover, the second highest in the Greater Mekong region, and a high deforestation rate (1.2%/year, 2005-2010). Community forestry (CF) has been proposed as a way to reduce deforestation and support livelihoods through local management of forests. CF is expanding rapidly in Cambodia. The National Forests Program aims to designate one million hectares of forest to CF by 2030. However, the effectiveness of CF in conservation is not clear due to a global lack of controlled comparisons, multiple meanings of CF, and the context-specific nature of CF implementation. We assessed the effectiveness of CF by comparing 9 CF sites with paired controls in state production forest in the area of Prey Long forest, Cambodia. We assessed forest condition in 18-20 randomly placed variable-radius plots and fixed-area regeneration plots. We surveyed 10% of households in each of the 9 CF villages to determine the proportion that used forest products, as a measure of household dependence on the forest. CF sites had fewer signs of anthropogenic damage (cut stems, stumps, and burned trees), higher aboveground biomass, more regenerating stems, and reduced canopy openness than control areas. Abundance of economically valuable species, however, was higher in control sites. We used survey results and geographic parameters to model factors affecting CF outcomes. Interaction between management type, CF or control, and forest dependence indicated that CF was more effective in cases where the community relied on forest products for subsistence use and income.

  11. Tree diversity, composition, forest structure and aboveground biomass dynamics after single and repeated fire in a Bornean rain forest.

    PubMed

    Slik, J W Ferry; Bernard, Caroline S; Van Beek, Marloes; Breman, Floris C; Eichhorn, Karl A O

    2008-12-01

    Forest fires remain a devastating phenomenon in the tropics that not only affect forest structure and biodiversity, but also contribute significantly to atmospheric CO2. Fire used to be extremely rare in tropical forests, leaving ample time for forests to regenerate to pre-fire conditions. In recent decades, however, tropical forest fires occur more frequently and at larger spatial scales than they used to. We studied forest structure, tree species diversity, tree species composition, and aboveground biomass during the first 7 years since fire in unburned, once burned and twice burned forest of eastern Borneo to determine the rate of recovery of these forests. We paid special attention to changes in the tree species composition during burned forest regeneration because we expect the long-term recovery of aboveground biomass and ecosystem functions in burned forests to largely depend on the successful regeneration of the pre-fire, heavy-wood, species composition. We found that forest structure (canopy openness, leaf area index, herb cover, and stem density) is strongly affected by fire but shows quick recovery. However, species composition shows no or limited recovery and aboveground biomass, which is greatly reduced by fire, continues to be low or decline up to 7 years after fire. Consequently, large amounts of the C released to the atmosphere by fire will not be recaptured by the burned forest ecosystem in the near future. We also observed that repeated fire, with an inter-fire interval of 15 years, does not necessarily lead to a huge deterioration in the regeneration potential of tropical forest. We conclude that burned forests are valuable and should be conserved and that long-term monitoring programs in secondary forests are necessary to determine their recovery rates, especially in relation to aboveground biomass accumulation.

  12. 36 CFR 20.2 - Permits; conditions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Permits; conditions. 20.2 Section 20.2 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR ISLE ROYALE NATIONAL PARK; COMMERCIAL FISHING § 20.2 Permits; conditions. Annual, revocable special...

  13. Application of AIS Technology to Forest Mapping

    NASA Technical Reports Server (NTRS)

    Yool, S. R.; Star, J. L.

    1985-01-01

    Concerns about environmental effects of large scale deforestation have prompted efforts to map forests over large areas using various remote sensing data and image processing techniques. Basic research on the spectral characteristics of forest vegetation are required to form a basis for development of new techniques, and for image interpretation. Examination of LANDSAT data and image processing algorithms over a portion of boreal forest have demonstrated the complexity of relations between the various expressions of forest canopies, environmental variability, and the relative capacities of different image processing algorithms to achieve high classification accuracies under these conditions. Airborne Imaging Spectrometer (AIS) data may in part provide the means to interpret the responses of standard data and techniques to the vegetation based on its relatively high spectral resolution.

  14. Changes in Orchid Bee Communities Across Forest-Agroecosystem Boundaries in Brazilian Atlantic Forest Landscapes.

    PubMed

    De Aguiar, Willian Moura; Sofia, Silvia H; Melo, Gabriel A R; Gaglianone, Maria Cristina

    2015-12-01

    Deforestation has dramatically reduced the extent of Atlantic Forest cover in Brazil. Orchid bees are key pollinators in neotropical forest, and many species are sensitive to anthropogenic interference. In this sense understanding the matrix permeability for these bees is important for maintaining genetic diversity and pollination services. Our main objective was to assess whether the composition, abundance, and diversity of orchid bees in matrices differed from those in Atlantic forest. To do this we sampled orchid bees at 4-mo intervals from 2007 to 2009 in remnants of Atlantic Forest, and in the surrounding pasture and eucalyptus matrices. The abundance, richness, and diversity of orchid bees diminished significantly from the forest fragment toward the matrix points in the eucalyptus and pasture. Some common or intermediate species in the forest areas, such as Eulaema cingulata (F.) and Euglossa fimbriata Moure, respectively, become rare species in the matrices. Our results show that the orchid bee community is affected by the matrices surrounding the forest fragments. They also suggest that connections between forest fragments need to be improved using friendly matrices that can provide more favorable conditions for bees and increase their dispersal between fragments.

  15. Monitoring forest structure at landscape level: a case study of Scots pine forest in NE Turkey.

    PubMed

    Terzioğlu, Salih; Başkent, Emin Zeki; Kadioğullari, Ali Ihsan

    2009-05-01

    This study aims to investigate the change in spatial-temporal configuration of secondary forest succession and generate measurements for monitoring the changes in structural plant diversity in Yalnizçam Scots pine forest in NE Turkey from 1972 to 2005. The successional stages were mapped using the combination of Geographic Information System (GIS), Global Positioning System (GPS), aerial photos and high resolution satellite images (IKONOS). Forest structure and its relationship with structural plant diversity along with its changes over time were characterized using FRAGSTATS. In terms of spatial configuration of seral stages, the total number of fragments increased from 572 to 735, and mean size of patch (MPS) decreased from 154.97 ha to 120.60 ha over 33 years. The situation resulted in forestation serving appropriate conditions for plant diversity in the area. As an overall change in study area, there was a net increase of 1823.3 ha forest during the period with an average annual forestation rate of 55.25 ha year(-1) (0.4% per year). In conclusion, the study revealed that stand type maps of forest management plans in Turkey provide a great chance to monitor the changes in structural plant diversity over time. The study further contributes to the development of a framework for effective integration of biodiversity conservation into Multiple Use Forest Management (MUFM) plans using the successional stages as a critical mechanism. PMID:18553149

  16. Forest fires in the insular Caribbean.

    PubMed

    Robbins, A Marcus J; Eckelmann, Claus-Martin; Quiñones, Maya

    2008-12-01

    This paper presents a summary of the forest fire reports in the insular Caribbean derived from both management reports and an analysis of publicly available Moderate Resolution Imaging Spectrodiometer (MODIS) satellite active fire products from the region. A vast difference between the amount of fires reported by land managers and fire points in the MODIS Fire Information for Resource Management System data can be observed. Future research is recommended to better understand the nature of these differences. While there is a general lack of available statistical data on forest fires in the Caribbean, a few general observations can be made: Forest fires occur mainly in dry forest types (500 to 1000 mm of mean annual rainfall). These are also the areas where most human settlements are located. Lowland high forests and montane forests with higher rainfall (1000 and more mm y(-1)) are less susceptible to forest fire, but they can burn in exceptionally dry years. Most of the dry forest ecosystems in the Caribbean can be considered to be fire-sensitive ecosystems, while the pine forests in the Caribbean (Cuba, Dominican Republic, and the Bahamas) are maintained by wildfires. In fire-sensitive ecosystems, uncontrolled burning often encourages the spread of alien invasive species. A Caribbean Fire Management Cooperation Strategy was developed between 2005 and 2006 under auspices of the Food and Agriculture Organization of the United Nations. This regional strategy aims to strengthen Caribbean fire management networking by encouraging closer collaboration among countries with similar ecological conditions. The strategy for the Caribbean identifies a number of research, training, and management activities to improve wildfire management capacity in the Caribbean.

  17. Forest fires in the insular Caribbean.

    PubMed

    Robbins, A Marcus J; Eckelmann, Claus-Martin; Quiñones, Maya

    2008-12-01

    This paper presents a summary of the forest fire reports in the insular Caribbean derived from both management reports and an analysis of publicly available Moderate Resolution Imaging Spectrodiometer (MODIS) satellite active fire products from the region. A vast difference between the amount of fires reported by land managers and fire points in the MODIS Fire Information for Resource Management System data can be observed. Future research is recommended to better understand the nature of these differences. While there is a general lack of available statistical data on forest fires in the Caribbean, a few general observations can be made: Forest fires occur mainly in dry forest types (500 to 1000 mm of mean annual rainfall). These are also the areas where most human settlements are located. Lowland high forests and montane forests with higher rainfall (1000 and more mm y(-1)) are less susceptible to forest fire, but they can burn in exceptionally dry years. Most of the dry forest ecosystems in the Caribbean can be considered to be fire-sensitive ecosystems, while the pine forests in the Caribbean (Cuba, Dominican Republic, and the Bahamas) are maintained by wildfires. In fire-sensitive ecosystems, uncontrolled burning often encourages the spread of alien invasive species. A Caribbean Fire Management Cooperation Strategy was developed between 2005 and 2006 under auspices of the Food and Agriculture Organization of the United Nations. This regional strategy aims to strengthen Caribbean fire management networking by encouraging closer collaboration among countries with similar ecological conditions. The strategy for the Caribbean identifies a number of research, training, and management activities to improve wildfire management capacity in the Caribbean. PMID:19205174

  18. Deposition of Mercury in Forests along a Montane Elevation Gradient.

    PubMed

    Blackwell, Bradley D; Driscoll, Charles T

    2015-05-01

    Atmospheric mercury (Hg) deposition varies along elevation gradients and is influenced by both orographic and biological factors. We quantified total Hg deposition over a 2 year period at 24 forest sites at Whiteface Mountain, NY, USA, that ranged from 450 to 1450 m above sea level and covered three distinct forest types: deciduous/hardwood forest (14.1 μg/m2-yr), spruce/fir forest (33.8 μg/m2-yr), and stunted growth alpine/fir forest (44.0 μg/m2-yr). Atmospheric Hg deposition increased with elevation, with the dominant deposition pathways shifting from litterfall in low-elevation hardwoods to throughfall in midelevation spruce/fir to cloudwater in high-elevation alpine forest. Soil Hg concentrations (ranging from 69 to 416 ng/g for the Oi/Oe and 72 to 598 ng/g for the Oa horizons) were correlated with total Hg deposition, but the weakness of the correlations suggests that additional factors such as climate and tree species also contribute to soil Hg accumulation. Meteorological conditions influenced Hg deposition pathways, as cloudwater Hg diminished in 2010 (dry conditions) compared to 2009 (wet conditions). However, the dry conditions in 2010 led to increased Hg dry deposition and subsequent significant increases in throughfall Hg fluxes compared to 2009. These findings suggest that elevation, forest characteristics, and meteorological conditions are all important drivers of atmospheric Hg deposition to montane forests.

  19. Reducing uncertainty for estimating forest carbon stocks and dynamics using integrated remote sensing, forest inventory and process-based modeling

    NASA Astrophysics Data System (ADS)

    Poulter, B.; Ciais, P.; Joetzjer, E.; Maignan, F.; Luyssaert, S.; Barichivich, J.

    2015-12-01

    Accurately estimating forest biomass and forest carbon dynamics requires new integrated remote sensing, forest inventory, and carbon cycle modeling approaches. Presently, there is an increasing and urgent need to reduce forest biomass uncertainty in order to meet the requirements of carbon mitigation treaties, such as Reducing Emissions from Deforestation and forest Degradation (REDD+). Here we describe a new parameterization and assimilation methodology used to estimate tropical forest biomass using the ORCHIDEE-CAN dynamic global vegetation model. ORCHIDEE-CAN simulates carbon uptake and allocation to individual trees using a mechanistic representation of photosynthesis, respiration and other first-order processes. The model is first parameterized using forest inventory data to constrain background mortality rates, i.e., self-thinning, and productivity. Satellite remote sensing data for forest structure, i.e., canopy height, is used to constrain simulated forest stand conditions using a look-up table approach to match canopy height distributions. The resulting forest biomass estimates are provided for spatial grids that match REDD+ project boundaries and aim to provide carbon estimates for the criteria described in the IPCC Good Practice Guidelines Tier 3 category. With the increasing availability of forest structure variables derived from high-resolution LIDAR, RADAR, and optical imagery, new methodologies and applications with process-based carbon cycle models are becoming more readily available to inform land management.

  20. Historical and current roles of insects and pathogens in eastern Oregon and Washington forested landscapes. Forest Service general technical report

    SciTech Connect

    Hessburg, P.F.; Mitchell, R.G.; Filip, G.M.

    1994-04-01

    The paper examines, by climax conifer series, historical and current roles of many important pathogens and insects of interior Northwest coniferious forests and their unique responses to changing successional conditions resulting from management. Future research on forest pathogens and insects should address three primary subject areas: insect and pathogen population dynamics in managed and unmanaged forests; ecological roles and effects of native and introduced pathogens and insects; and effects of natural disturbances and management practices on native insects, pathogens, and their natural enemies.

  1. Rain forest preservation

    SciTech Connect

    Weiner, R.F. )

    1989-01-01

    The author discusses the possible impact the destruction of the tropical rain forest in South America has had on the atmosphere. Slash-and-burn agricultural practices have caused laterization of the soils, because rain forest vegetation carries nutrients, rather than the soil. The fact that the vegetation of the rain forest can help metabolize the excess carbon dioxide in the atmosphere is also mentioned.

  2. Forest Fires in a Random Forest

    NASA Astrophysics Data System (ADS)

    Leuenberger, Michael; Kanevski, Mikhaïl; Vega Orozco, Carmen D.

    2013-04-01

    Forest fires in Canton Ticino (Switzerland) are very complex phenomena. Meteorological data can explain some occurrences of fires in time, but not necessarily in space. Using anthropogenic and geographical feature data with the random forest algorithm, this study tries to highlight factors that most influence the fire-ignition and to identify areas under risk. The fundamental scientific problem considered in the present research deals with an application of random forest algorithms for the analysis and modeling of forest fires patterns in a high dimensional input feature space. This study is focused on the 2,224 anthropogenic forest fires among the 2,401 forest fire ignition points that have occurred in Canton Ticino from 1969 to 2008. Provided by the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), the database characterizes each fire by their location (x,y coordinates of the ignition point), start date, duration, burned area, and other information such as ignition cause and topographic features such as slope, aspect, altitude, etc. In addition, the database VECTOR25 from SwissTopo was used to extract information of the distances between fire ignition points and anthropogenic structures like buildings, road network, rail network, etc. Developed by L. Breiman and A. Cutler, the Random Forests (RF) algorithm provides an ensemble of classification and regression trees. By a pseudo-random variable selection for each split node, this method grows a variety of decision trees that do not return the same results, and thus by a committee system, returns a value that has a better accuracy than other machine learning methods. This algorithm incorporates directly measurement of importance variable which is used to display factors affecting forest fires. Dealing with this parameter, several models can be fit, and thus, a prediction can be made throughout the validity domain of Canton Ticino. Comprehensive RF analysis was carried out in order to 1

  3. 3. View northeast, west facade of Lake Forest (original Forest ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. View northeast, west facade of Lake Forest (original Forest Cottage structure incorporated into renamed structure) - Lake Placid Club, Forest Wing, East side of Mirror Lake Drive, North of State Route 86 & Main, North Elba, Essex County, NY

  4. 4. View southeast, west facade of Lake Forest (original Forest ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. View southeast, west facade of Lake Forest (original Forest Cottage structure incorporated into renamed structure) - Lake Placid Club, Forest Wing, East side of Mirror Lake Drive, North of State Route 86 & Main, North Elba, Essex County, NY

  5. 7. View southwest, east facade of Lake Forest (original Forest ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. View southwest, east facade of Lake Forest (original Forest Cottage structure incorporated into renamed structure) - Lake Placid Club, Forest Wing, East side of Mirror Lake Drive, North of State Route 86 & Main, North Elba, Essex County, NY

  6. Fire and forest history at Mount Rushmore.

    PubMed

    Brown, Peter M; Wienk, Cody L; Symstad, Amy J

    2008-12-01

    Mount Rushmore National Memorial in the Black Hills of South Dakota is known worldwide for its massive sculpture of four of the United States' most respected presidents. The Memorial landscape also is covered by extensive ponderosa pine (Pinus ponderosa) forest that has not burned in over a century. We compiled dendroecological and forest structural data from 29 plots across the 517-ha Memorial and used fire behavior modeling to reconstruct the historical fire regime and forest structure and compare them to current conditions. The historical fire regime is best characterized as one of low-severity surface fires with occasional (> 100 years) patches (< 100 ha) of passive crown fire. We estimate that only approximately 3.3% of the landscape burned as crown fire during 22 landscape fire years (recorded at > or = 25% of plots) between 1529 and 1893. The last landscape fire was in 1893. Mean fire intervals before 1893 varied depending on spatial scale, from 34 years based on scar-to-scar intervals on individual trees to 16 years between landscape fire years. Modal fire intervals were 11-15 years and did not vary with scale. Fire rotation (the time to burn an area the size of the study area) was estimated to be 30 years for surface fire and 800+ years for crown fire. The current forest is denser and contains more small trees, fewer large trees, lower canopy base heights, and greater canopy bulk density than a reconstructed historical (1870) forest. Fire behavior modeling using the NEXUS program suggests that surface fires would have dominated fire behavior in the 1870 forest during both moderate and severe weather conditions, while crown fire would dominate in the current forest especially under severe weather. Changes in the fire regime and forest structure at Mount Rushmore parallel those seen in ponderosa pine forests from the southwestern United States. Shifts from historical to current forest structure and the increased likelihood of crown fire justify the need for

  7. Fire and forest history at Mount Rushmore.

    PubMed

    Brown, Peter M; Wienk, Cody L; Symstad, Amy J

    2008-12-01

    Mount Rushmore National Memorial in the Black Hills of South Dakota is known worldwide for its massive sculpture of four of the United States' most respected presidents. The Memorial landscape also is covered by extensive ponderosa pine (Pinus ponderosa) forest that has not burned in over a century. We compiled dendroecological and forest structural data from 29 plots across the 517-ha Memorial and used fire behavior modeling to reconstruct the historical fire regime and forest structure and compare them to current conditions. The historical fire regime is best characterized as one of low-severity surface fires with occasional (> 100 years) patches (< 100 ha) of passive crown fire. We estimate that only approximately 3.3% of the landscape burned as crown fire during 22 landscape fire years (recorded at > or = 25% of plots) between 1529 and 1893. The last landscape fire was in 1893. Mean fire intervals before 1893 varied depending on spatial scale, from 34 years based on scar-to-scar intervals on individual trees to 16 years between landscape fire years. Modal fire intervals were 11-15 years and did not vary with scale. Fire rotation (the time to burn an area the size of the study area) was estimated to be 30 years for surface fire and 800+ years for crown fire. The current forest is denser and contains more small trees, fewer large trees, lower canopy base heights, and greater canopy bulk density than a reconstructed historical (1870) forest. Fire behavior modeling using the NEXUS program suggests that surface fires would have dominated fire behavior in the 1870 forest during both moderate and severe weather conditions, while crown fire would dominate in the current forest especially under severe weather. Changes in the fire regime and forest structure at Mount Rushmore parallel those seen in ponderosa pine forests from the southwestern United States. Shifts from historical to current forest structure and the increased likelihood of crown fire justify the need for

  8. Life in Tropical Rain Forests.

    ERIC Educational Resources Information Center

    NatureScope, 1989

    1989-01-01

    Discusses the diversity of rain forest life, the adaptations of rain forest plants and animals, and ways these organisms interact. Includes activities on canopy critters with a copyable sheet, rain forest revue, design a plant, and jungle sleuths. (RT)

  9. Managing the world's forests.

    PubMed

    Sharma, N; Rowe, R

    1992-06-01

    Forests play a vital role in balancing natural systems: the stabilization of global climate and the management of water and land. 30% of the earth's total land area is forested. 66% of the tropical moist forests are in Latin America and the remainder in Africa and Asia. 75% of tropical dry forests are in Africa. Temperate forests are primarily in developed countries. Deforestation and misuse of forests occurs primarily in developing countries at significant social, economic, and environmental costs. Losses have occurred in fuelwood, fodder, timber, forest products, biological diversity, habitats, genetic materials for food and medicine. The World Bank's evolving role in forestry is briefly described. Agreement has not been reached among people or nations about the most appropriate means to balance conservation and development goals. The challenge is to stabilize existing forests and increase forest planting. The causes of forest degradation must be understood. Direct causes include agricultural encroachment, cattle ranching, fuelwood gathering, commercial logging, and infrastructure development. These direct causes are driven by economic, social, and political forces: market and policy failures, population growth, and poverty. The market failures include: 1) the lack of clearly defined property rights on forest resources for now and the future, 2) the conflict between individual and societal needs, 3) the difficulty in placing a value on nonmarket environmental services and joint products, and 4) the separation between private and social costs. The solution is action at the local, national, and global levels. Countries must establish forest policy. The existing government incentives which promote deforestation must be changed. For example, concession policy and royalty systems must be corrected; explicit and implicit export subsidies on timber and forest products must be stopped. Private incentives must be established to promote planting of trees, practicing

  10. Agricultural legacies in forest environments: tree communities, soil properties, and light availability.

    PubMed

    Flinn, Kathryn M; Marks, P L

    2007-03-01

    Temperate deciduous forests across much of Europe and eastern North America reflect legacies of past land use, particularly in the diversity and composition of plant communities. Intense disturbances, such as clearing forests for agriculture, may cause persistent environmental changes that continue to shape vegetation patterns as landscapes recover. We assessed the long-term consequences of agriculture for environmental conditions in central New York forests, including tree community structure and composition, soil physical and chemical properties, and light availability. To isolate the effects of agriculture, we compared 20 adjacent pairs of forests that were never cleared for agriculture (primary forests) and forests that established 85-100 years ago on plowed fields (secondary forests). Tree communities in primary and secondary forests had similar stem density, though secondary forests had 14% greater basal area. Species composition differed dramatically between the two forest types, with primary forests dominated by Acer saccharum and Fagus grandifolia and secondary forests by Acer rubrum and Pinus strobus. Primary and secondary forests showed no consistent differences in soil physical properties or in the principal gradient of soil fertility associated with soil pH. Within stands, however, soil water content and pH were more variable in primary forests. Secondary forest soils had 15% less organic matter, 16% less total carbon, and 29% less extractable phosphorus in the top 10 cm than adjacent primary stands, though the ranges of the forest types mostly overlapped. Understory light availability in primary and secondary forests was similar. These results suggest that, within 100 years, post-agricultural stands have recovered conditions comparable to less disturbed forests in many attributes, including tree size and number, soil physical properties, soil chemical properties associated with pH, and understory light availability. The principal legacies of

  11. Selection of roosting habitat by forest bats in a diverse forested landscape

    USGS Publications Warehouse

    Perry, R.W.; Thill, R.E.; Leslie, David M.

    2007-01-01

    Many studies of roost selection by forest-dwelling bats have concentrated on microhabitat surrounding roosts without providing forest stand-level preferences of bats; thus, those studies have provided only part of the information needed by managers. We evaluated diurnal summer roost selection by the bat community at the forest-stand level in a diversely forested landscape in the Ouachita Mountains of central Arkansas. Over a 6-year period, we evaluated 428 roost locations for 162 individual bats of 6 species. Using Euclidean distance analysis and individual bat as the experimental unit, all 6 species were selective (P < 0.05) in their choice of roosting habitat. Five of six species preferred (P < 0.05) to roost in or near mature (???50 years old), mixed pine-hardwood forest that had undergone recent partial harvest, midstory removal, and burning; 41.3% of roosts were located in that habitat but it comprised an average of only 22.8% of available habitat. Five of six species also preferred older (???100 years old), relatively unmanaged, mixed pine-hardwood forest. Although 19.9% of roosts from all species were located in 50- to 99-year-old, second-growth forests of mixed pine-hardwood (average of 21.0% of available habitat), that habitat was preferred by no species of bat. In partially harvested stands, unharvested buffer strips (greenbelts) surrounding ephemeral streams were used at differing levels by each species; most (90%) eastern pipistrelle (Pipistrellus subflavus) roosts were in greenbelts whereas few (2.7%) Seminole bat (Lasiurus seminolus) roosts were in greenbelts. Older forests, thinned mature forests with reduced midstories, and greenbelts retained in harvested areas were all important roosting habitats for the bat community in the Ouachita Mountains. Our results demonstrate the importance of open forest conditions and a diversity of stand types to bat communities of the southeastern U.S.

  12. Permafrost and Forest Degradation after Wet Climate Years in Eastern Siberian Boreal Forest

    NASA Astrophysics Data System (ADS)

    Iijima, Y.; Abe, K.; Ise, H.; Masuzawa, T.; Fedorov, A. N.

    2014-12-01

    Unusual precipitation increase during summer through winter had continued since 2004 in the central Lena river basin, eastern Siberia. The precipitation increase led to deepening active layer (permafrost thawing near the surface) accompanying with remarkable increase in soil moisture. The perennially waterlogged conditions had exacerbated the boreal forest habitat; that is, larch trees had widely withered and died in this region. The present study clarified spatial extent of permafrost and forest degradation due to the unexpected hydro-climate-driven damages. We have attempted to extract the degraded boreal forest based on satellite image analyses, along with expansion of the perennially waterlogged surface area. We used ALOS-PALSAR and AVNIR-2 images taken from 2006 to 2009. Classification of waterlogged area was performed by PALSAR images with supervised classification based on a microwave backscattering coefficient. Then, we compared the distribution of the waterlogged area between multi-years. Additional supervised classification of boreal forest change was conducted using AVNIR-2 images. Both classifications produced the multi-years change in degraded boreal forest at the intensive observational sites in both left and right bank of Lena River near Yakutsk. In the right bank area, most of alas lakes expanded and boreal forest on the periphery of lakes turned to waterlogged surface. In the left bank area, in contrast, waterlogged surface expanded at concaved terrain and along valleys in conjunction with forest degradation. Field survey supported that humidified and deepening active layer along slope and near alas lakes correspond with the gradient of forest degradation and enhanced thermokarst activity. Both of increasing precipitation and thawing ice in permafrost might cause the degradation. In brief, the method combining ALOS satellite images has possibility to detect permafrost and forest degradation caused by wet climate in boreal forest.

  13. People and Forests.

    ERIC Educational Resources Information Center

    NatureScope, 1986

    1986-01-01

    Provides: (1) background information on how forests are managed and some of the problems facing forests around the world; (2) three activities dealing with these topics; and (3) three ready-to-copy pages for student use. Activities include an objective, recommended age level(s), recommended subject area(s), list of materials needed, and…

  14. The National Forests

    ERIC Educational Resources Information Center

    Clawson, Marion

    1976-01-01

    National forests are a valuable national asset in terms of wood, recreation, wilderness, wildlife, and water. Management is inefficient and uneconomic creating wasteful capital investment and below-potential economic output. Better national leadership, analysis of forests as a business enterprise, and recruitment of outside persons into Forest…

  15. Trading forest carbon

    EPA Science Inventory

    The nature of carbon in forests is discussed from the perspective of carbon trading. Carbon inventories, specifically in the area of land use and forestry are reviewed for the Pacific Northwest. Carbon turnover in forests is discussed as it relates to carbon sequestration. Scient...

  16. People & Tropical Rain Forests.

    ERIC Educational Resources Information Center

    NatureScope, 1989

    1989-01-01

    Discusses ways people who live in rain forests make a living and some of the products that enrich our lives. Provides activities covering forest people, tropical treats, jungle in the pantry, treetop explorers, and three copyable pages to accompany activities. (Author/RT)

  17. Application of China's National Forest Continuous Inventory database.

    PubMed

    Xie, Xiaokui; Wang, Qingli; Dai, Limin; Su, Dongkai; Wang, Xinchuang; Qi, Guang; Ye, Yujing

    2011-12-01

    The maintenance of a timely, reliable and accurate spatial database on current forest ecosystem conditions and changes is essential to characterize and assess forest resources and support sustainable forest management. Information for such a database can be obtained only through a continuous forest inventory. The National Forest Continuous Inventory (NFCI) is the first level of China's three-tiered inventory system. The NFCI is administered by the State Forestry Administration; data are acquired by five inventory institutions around the country. Several important components of the database include land type, forest classification and ageclass/ age-group. The NFCI database in China is constructed based on 5-year inventory periods, resulting in some of the data not being timely when reports are issued. To address this problem, a forest growth simulation model has been developed to update the database for years between the periodic inventories. In order to aid in forest plan design and management, a three-dimensional virtual reality system of forest landscapes for selected units in the database (compartment or sub-compartment) has also been developed based on Virtual Reality Modeling Language. In addition, a transparent internet publishing system for a spatial database based on open source WebGIS (UMN Map Server) has been designed and utilized to enhance public understanding and encourage free participation of interested parties in the development, implementation, and planning of sustainable forest management.

  18. Application of China's National Forest Continuous Inventory Database

    NASA Astrophysics Data System (ADS)

    Xie, Xiaokui; Wang, Qingli; Dai, Limin; Su, Dongkai; Wang, Xinchuang; Qi, Guang; Ye, Yujing

    2011-12-01

    The maintenance of a timely, reliable and accurate spatial database on current forest ecosystem conditions and changes is essential to characterize and assess forest resources and support sustainable forest management. Information for such a database can be obtained only through a continuous forest inventory. The National Forest Continuous Inventory (NFCI) is the first level of China's three-tiered inventory system. The NFCI is administered by the State Forestry Administration; data are acquired by five inventory institutions around the country. Several important components of the database include land type, forest classification and ageclass/ age-group. The NFCI database in China is constructed based on 5-year inventory periods, resulting in some of the data not being timely when reports are issued. To address this problem, a forest growth simulation model has been developed to update the database for years between the periodic inventories. In order to aid in forest plan design and management, a three-dimensional virtual reality system of forest landscapes for selected units in the database (compartment or sub-compartment) has also been developed based on Virtual Reality Modeling Language. In addition, a transparent internet publishing system for a spatial database based on open source WebGIS (UMN Map Server) has been designed and utilized to enhance public understanding and encourage free participation of interested parties in the development, implementation, and planning of sustainable forest management.

  19. Modelling interactions of carbon dioxide, forests, and climate

    SciTech Connect

    Luxmoore, R.J.; Baldocchi, D.D.

    1994-09-01

    Atmospheric carbon dioxide is rising and forests and climate is changing! This combination of fact and premise may be evaluated at a range of temporal and spatial scales with the aid of computer simulators describing the interrelationships between forest vegetation, litter and soil characteristics, and appropriate meteorological variables. Some insights on the effects of climate on the transfers of carbon and the converse effect of carbon transfer on climate are discussed as a basis for assessing the significance of feedbacks between vegetation and climate under conditions of rising atmospheric carbon dioxide. Three main classes of forest models are reviewed. These are physiologically-based models, forest succession simulators based on the JABOWA model, and ecosystem-carbon budget models that use compartment transfer rates with empirically estimated coefficients. Some regression modeling approaches are also outlined. Energy budget models applied to forests and grasslands are also reviewed. This review presents examples of forest models; a comprehensive discussion of all available models is not undertaken.

  20. Atmospheric deposition to high-elevation forests

    SciTech Connect

    Lovett, G.M.; Weathers, K.C.; Lindberg, S.E. Oak Ridge National Lab., TN )

    1994-06-01

    Three important phenomena characterize atmospheric deposition to high-elevation forests: (1) multiple deposition mechanisms (wet, dry, and cloud deposition), (2) high rates of deposition, and (3) high spatial variability. The high rates of deposition are caused by changes in meteorological conditions with elevation, especially increasing wind speed and cloud immersion frequency. The high spatial variability of deposition is a result of the regulation of cloud and dry deposition rates by microclimatic and canopy structure conditions, which can be extremely heterogeneous in mountain landscapes. Spruce-fir forests are often [open quotes]hot spots[close quotes] of deposition when viewed in a landscape or regional context because of their elevation, exposure, and evergreen canopy. In this talk we will consider atmospheric depositions to high-elevation forests in both the northeastern and southeastern U.S., using field data and geographic information systems to illustrate deposition patterns.

  1. Forest Pest Occurrence Predictionca-Markov Model

    NASA Astrophysics Data System (ADS)

    Xie, Fangyi; Zhang, Xiaoli; Chen, Xiaoyan

    Since the spatial pattern of forest pest occurrence is determined by biological characteristics and habitat conditions, this paper introduced construction of a cellular automaton model combined with Markov model to predicate the forest pest occurrence. Rules of the model includes the cell states rules, neighborhood rules and transition rules which are defined according to the factors from stand conditions, stand structures, climate and the influence of the factors on the state conversion. Coding for the model is also part of the implementations of the model. The participants were designed including attributes and operations of participants expressed with a UML diagram. Finally, the scale issues on forest pest occurrence prediction, of which the core are the prediction of element size and time interval, are partly discussed in this paper.

  2. Designing Forest Adaptation Experiments through Manager-Scientist Partnerships

    NASA Astrophysics Data System (ADS)

    Nagel, L. M.; Swanston, C.; Janowiak, M.

    2014-12-01

    Three common forest adaptation options discussed in the context of an uncertain future climate are: creating resistance, promoting resilience, and enabling forests to respond to change. Though there is consensus on the broad management goals addressed by each of these options, translating these concepts into management plans specific for individual forest types that vary in structure, composition, and function remains a challenge. We will describe a decision-making framework that we employed within a manager-scientist partnership to develop a suite of adaptation treatments for two contrasting forest types as part of a long-term forest management experiment. The first, in northern Minnesota, is a red pine-dominated forest with components of white pine, aspen, paper birch, and northern red oak, with a hazel understory. The second, in southwest Colorado, is a warm-dry mixed conifer forest dominated by ponderosa pine, white fir, and Douglas-fir, with scattered aspen and an understory of Gambel oak. The current conditions at both sites are characterized by overstocking with moderate-to-high fuel loading, vulnerability to numerous forest health threats, and are generally uncharacteristic of historic structure and composition. The desired future condition articulated by managers for each site included elements of historic structure and natural range of variability, but were greatly tempered by known vulnerabilities and projected changes to climate and disturbance patterns. The resultant range of treatments we developed are distinct for each forest type, and address a wide range of management objectives.

  3. [Establishment of standard forest fuel models for Fenglin Natural Reserve, Heilongjiang Province, China].

    PubMed

    Wu, Zhi-Wei; He, Hong-Shi; Liang, Yu; Luo, Xu; Cai, Long-Yan; Long, Jing

    2012-06-01

    From the viewpoint of forest fire behavior, and based on the key parameters of fuels, three standard forest fuel models for the forests differed significantly in fuel characteristics and local environmental conditions in Fenglin Natural Reserve were established by using hierarchical cluster analysis. The three models were FL-I, FL-II, and FL-III for the broadleaved-Korean pine forest, spruce-fir forest, and poplar-birch forest, the representative forest types in the Reserve, respectively. According to the forest structure and composition, land cover type, and horizontal and vertical continuity, the three models FL-I , FL-II, and FL-III were similar to the models C-5, C-2, and D-1 in Canada CFBPS fuel classification system, respectively. The forest ground features and the horizontal and vertical characteristics of the three models established in this paper could help the investigators to identify the fuel types in fuel inventory.

  4. 78 FR 73819 - Forest Resource Coordinating Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-09

    ... Forest Service Forest Resource Coordinating Committee AGENCY: Forest Service, USDA. ACTION: Notice of...-18, 2013 meeting of the Forest Resource Coordinating Committee due to the Government partial shutdown... INFORMATION CONTACT: Maya Solomon, Forest Resource Coordinating Committee Program Coordinator; by phone...

  5. 76 FR 22363 - Kaibab National Forest, Williams Ranger District; Arizona; Bill Williams Mountain Restoration...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-21

    ... Forest Service Kaibab National Forest, Williams Ranger District; Arizona; Bill Williams Mountain... forested conditions on and surrounding Bill Williams Mountain by reducing hazardous fuels and moving... approximately 4 miles south-southwest of the city of Williams, Arizona. The Proposed Action includes...

  6. Effects of elevated CO2 and temperature on forest floor litter decomposition and chemistry

    EPA Science Inventory

    Forest floor can be a major component of the carbon held in forested soils. In mature forests it represents the balance between additions and decomposition under current climate conditions. Because of its position at the soil surface, this reservoir of C is highly susceptible...

  7. The southern Appalachian forests

    USGS Publications Warehouse

    Ayres, H.B.; Ashe, W.W.

    1905-01-01

    In examining so large an area it was found that the best results could be obtained by traversing the roads and trails and making side trips wherever necessary to cover intermediate territory. Upon the topographic maps of the Geological Survey were drawn the outlines of cleared land and the several classes of forest land as they were passed. At the same time ocular estimates of the average stand and the proportion of the species composing it were made, checked occasionally by actual measurements on small representative areas. After the outlines of the several classes of land were drawn the areas were computed from the map, and the yield obtained by multiplying the number of acres of each class by the average stand. The yield is stated in feet B. M. of log timber, and cords of small wood (which includes all wood not classed as log timber). The estimates of log timber were based upon the closest cutting in practice in the United States, and include a great deal of material that is not now salable on the stump, because of the difficulty of transportation. In fact, a very small proportion of the amount estimated (probably not over 10 per cent) is merchantable under present conditions, though all would be merchantable if cheap transportation should make it accessible.

  8. Ant community structure during forest succession in a subtropical forest in South-East China

    NASA Astrophysics Data System (ADS)

    Staab, Michael; Schuldt, Andreas; Assmann, Thorsten; Bruelheide, Helge; Klein, Alexandra-Maria

    2014-11-01

    Understanding how communities respond to environmental gradients is critical to predict responses of species to changing habitat conditions such as in regenerating secondary habitats after human land use. In this study, ground-living ants were sampled with pitfall traps in 27 plots in a heterogeneous and diverse subtropical forest to test if and how a broad set of environmental variables including elevation, successional age, and tree species richness influence ant diversity and community composition. In total, 13,441 ant individuals belonging to 71 species were found. Ant abundance was unrelated to all environmental variables. Rarefied ant species richness was negatively related to elevation, and Shannon diversity decreased with shrub cover. There was considerable variation in ant species amongst plots, associated with elevation, successional age, and variables related to succession such as shrub cover. It is shown that younger secondary forests may support a species-rich and diverse community of ants in subtropical forests even though the species composition between younger and older forests is markedly different. These findings confirm the conservation value of secondary subtropical forests, which is critical because subtropical forests have been heavily exploited by human activities globally. However, the findings also confirm that old-growth forest should have priority in conservation as it supports a distinct ant community. Our study identifies a set of ant species which are associated with successional age and may thus potentially assist local conservation planning.

  9. Forest-Water Feedbacks Under a Changing Climate

    NASA Astrophysics Data System (ADS)

    Creed, I. F.; Hwang, T.

    2015-12-01

    Among the most valuable products produced by forests are the ecosystem services of safe and reliable water supplies. The provision of these ecosystem services on forested landscapes is inherently linked to forest condition. Climate change and associated hydrological intensification may affect forest water use (green water) and runoff generation (blue water) in the temperate forest biome of eastern North America. For the time period from the 1980s to present, a period with significant climate warming, we used a network of long-term catchment study sites nested within the temperate forest biome to explore forest-water feedbacks in response to climate change. Satellite remote sensing was used to track changes in forest phenology and forest productivity, and catchment meteorological and discharge records were used to track changes in the magnitude and timing of forest water yields. Forest responses to climate change varied along a latitudinal gradient. The magnitude of annual water yields declined at all study sites. The timing of peak discharge was measured by the center of mass (i.e., 50th percentile), and the narrowing or widening of discharge periods was measured by the coefficient of dispersion (i.e., 75th - 25th over 50th percentile) of water yield. For the vernal window, we observed subtle and systematic changes with a shift to later peaks in the center of mass of spring discharge and a widening of the spring discharge period (i.e., less peaked flows). For the autumnal window, we observed less subtle, non-systematic changes with a shift to later peaks above 45 degrees latitude but earlier peaks below 45 degrees latitude, and a narrowing of the fall discharge period (i.e., more peaked flows). The time shift and widening of vernal and autumnal windows are likely caused by asymmetric responses of forest water use (green water) and runoff generation (blue water) to climate warming. These disruptions in forest-water coupling are likely to have significant

  10. Climate Change Impacts on Forest Succession and Future Productivity

    NASA Astrophysics Data System (ADS)

    Mohan, J. E.; Melillo, J. M.; Clark, J. S.; Schlesinger, W. H.

    2012-12-01

    Change in ecosystem carbon (C) dynamics with forest succession is a long-studied topic in ecology, and secondary forests currently comprise a significant proportion of the global land base. Although mature forests are generally more important for conserving species and habitats, early successional trees and stands typically have higher rates of productivity, including net ecosystem productivity (NEP), which represents carbon available for sequestration. Secondary forests undergoing successional development are thus major players in the current global carbon cycle, yet how forests will function in the future under warmer conditions with higher atmospheric carbon dioxide (CO2) concentrations is unknown. Future forest C dynamics will depend, in part, on future species composition. Data from "Forests of the Future" research in a number of global change experiments provide insights into how forests may look in terms of dominant species composition, and thus function, in a future world. Studies at Free-Air Carbon Dioxide (FACE) experiments at Duke Forest and other facilities, plus climate warming experiments such as those at the Harvard Forest, suggest a common underlying principle of vegetation responses to environmental manipulation: Namely, that shade-tolerant woody species associating with arbuscular mycorrhizal (AM) fungi show greater growth stimulation than ectomycorrhizal-associating (ECM) trees which are more common in temperate and boreal forests (Fig. 1 of relative growth rates standardized by pre-treatment rates). This may be due in part to the role of AM fungi in obtaining soil phosphorus and inorganic forms of nitrogen for plant associates. In combination, these results suggest a shift in future forest composition towards less-productive tree species that generally acquire atmospheric CO2 at lower annual rates, as well as a competitive advantage extended to woody vines such as poison ivy. Due to higher atmospheric CO2 and warmer temperatures, forests of the

  11. Preliminary geologic map of the Chugach National Forest Special Study Area, Alaska

    USGS Publications Warehouse

    Nelson, Steven W.; Miller, Marti L.; Haeussler, Peter J.; Snee, Lawrence W.; Philips, Patti J.; Huber, Carol

    1999-01-01

    In 1990, both the U.S. Geological Survey and U.S. Bureau of Mines were contacted by the Chugach National Forest (CNF) for the purpose of providing mineral resource information for the CNF Master Plan during the planning period fiscal years 1991-1994. This information is to address the terms and requirements of the 1986 Settlement Agreement and to provide mineral and geologic information useful to the CNF for making land-use decisions. In early 1992 an Interagency Agreement between the U.S. Geological Survey, the U.S. Bureau of Mines and the Chugach National Forest was signed. In this agreement the U.S. Geological Survey is to provide a report which estimates the undiscovered mineral endowments of the 'special' study area and to identify the potential for mineral discovery and development. The U.S. Bureau of Mines was to prepare a report updating the discovered mineral endowment of the Special Study Area. These reports are now published (Roe and Balen, 1994; Nelson and others, 1994). This geologic map is a component of the U.S. Geological Survey contribution to the overall project.

  12. Forest structure in low-diversity tropical forests: a study of Hawaiian wet and dry forests.

    PubMed

    Ostertag, Rebecca; Inman-Narahari, Faith; Cordell, Susan; Giardina, Christian P; Sack, Lawren

    2014-01-01

    The potential influence of diversity on ecosystem structure and function remains a topic of significant debate, especially for tropical forests where diversity can range widely. We used Center for Tropical Forest Science (CTFS) methodology to establish forest dynamics plots in montane wet forest and lowland dry forest on Hawai'i Island. We compared the species diversity, tree density, basal area, biomass, and size class distributions between the two forest types. We then examined these variables across tropical forests within the CTFS network. Consistent with other island forests, the Hawai'i forests were characterized by low species richness and very high relative dominance. The two Hawai'i forests were floristically distinct, yet similar in species richness (15 vs. 21 species) and stem density (3078 vs. 3486/ha). While these forests were selected for their low invasive species cover relative to surrounding forests, both forests averaged 5->50% invasive species cover; ongoing removal will be necessary to reduce or prevent competitive impacts, especially from woody species. The montane wet forest had much larger trees, resulting in eightfold higher basal area and above-ground biomass. Across the CTFS network, the Hawaiian montane wet forest was similar to other tropical forests with respect to diameter distributions, density, and aboveground biomass, while the Hawai'i lowland dry forest was similar in density to tropical forests with much higher diversity. These findings suggest that forest structural variables can be similar across tropical forests independently of species richness. The inclusion of low-diversity Pacific Island forests in the CTFS network provides an ∼80-fold range in species richness (15-1182 species), six-fold variation in mean annual rainfall (835-5272 mm yr(-1)) and 1.8-fold variation in mean annual temperature (16.0-28.4°C). Thus, the Hawaiian forest plots expand the global forest plot network to enable testing of ecological theory for

  13. Forest Fragmentation and Selective Logging Have Inconsistent Effects on Multiple Animal-Mediated Ecosystem Processes in a Tropical Forest

    PubMed Central

    Schleuning, Matthias; Farwig, Nina; Peters, Marcell K.; Bergsdorf, Thomas; Bleher, Bärbel; Brandl, Roland; Dalitz, Helmut; Fischer, Georg; Freund, Wolfram; Gikungu, Mary W.; Hagen, Melanie; Garcia, Francisco Hita; Kagezi, Godfrey H.; Kaib, Manfred; Kraemer, Manfred; Lung, Tobias; Schaab, Gertrud; Templin, Mathias; Uster, Dana; Wägele, J. Wolfgang; Böhning-Gaese, Katrin

    2011-01-01

    Forest fragmentation and selective logging are two main drivers of global environmental change and modify biodiversity and environmental conditions in many tropical forests. The consequences of these changes for the functioning of tropical forest ecosystems have rarely been explored in a comprehensive approach. In a Kenyan rainforest, we studied six animal-mediated ecosystem processes and recorded species richness and community composition of all animal taxa involved in these processes. We used linear models and a formal meta-analysis to test whether forest fragmentation and selective logging affected ecosystem processes and biodiversity and used structural equation models to disentangle direct from biodiversity-related indirect effects of human disturbance on multiple ecosystem processes. Fragmentation increased decomposition and reduced antbird predation, while selective logging consistently increased pollination, seed dispersal and army-ant raiding. Fragmentation modified species richness or community composition of five taxa, whereas selective logging did not affect any component of biodiversity. Changes in the abundance of functionally important species were related to lower predation by antbirds and higher decomposition rates in small forest fragments. The positive effects of selective logging on bee pollination, bird seed dispersal and army-ant raiding were direct, i.e. not related to changes in biodiversity, and were probably due to behavioural changes of these highly mobile animal taxa. We conclude that animal-mediated ecosystem processes respond in distinct ways to different types of human disturbance in Kakamega Forest. Our findings suggest that forest fragmentation affects ecosystem processes indirectly by changes in biodiversity, whereas selective logging influences processes directly by modifying local environmental conditions and resource distributions. The positive to neutral effects of selective logging on ecosystem processes show that the

  14. Forest pathology in Hawaii

    USGS Publications Warehouse

    Gardner, D.E.

    2003-01-01

    Native Hawaiian forests are characterised by a high degree of endemism, including pathogens as well as their hosts. With the exceptions of koa (Acacia koa Gray), possibly maile (Alyxia oliviformis Gaud.), and, in the past, sandalwood (Santalum spp.), forest species are of little commercial value. On the other hand, these forests are immensely important from a cultural, ecological, and evolutionary standpoint. Forest disease research was lacking during the mid-twentieth century, but increased markedly with the recognition of ohia (Metrosideros polymorpha Gaud.) decline in the 1970s. Because many pathogens are themselves endemic, or are assumed to be, having evolved with their hosts, research emphasis in natural areas is on understanding host-parasite interactions and evolutionary influences, rather than disease control. Aside from management of native forests, attempts at establishing a commercial forest industry have included importation of several species of pine, Araucaria, and Eucalyptus as timber crops, and of numerous ornamentals. Diseases of these species have been introduced with their hosts. The attacking of native species by introduced pathogens is problematic - for example, Armillaria mellea (Vahl ex Fr.) Que??l. on koa and mamane (Sophora chrysophylla (Salisb.) Seem.). Much work remains to be done in both native and commercial aspects of Hawaiian forest pathology.

  15. Influence of forest management regimes on forest dynamics in the upstream region of the Hun River in northeastern China.

    PubMed

    Yao, Jing; He, Xingyuan; Wang, Anzhi; Chen, Wei; Li, Xiaoyu; Lewis, Bernard J; Lv, Xiaotao

    2012-01-01

    Balancing forest harvesting and restoration is critical for forest ecosystem management. In this study, we used LANDIS, a spatially explicit forest landscape model, to evaluate the effects of 21 alternative forest management initiatives which were drafted for forests in the upstream region of the Hun River in northeastern China. These management initiatives included a wide range of planting and harvest intensities for Pinus koraiensis, the historically dominant tree species in the region. Multivariate analysis of variance, Shannon's Diversity Index, and planting efficiency (which indicates how many cells of the target species at the final year benefit from per-cell of the planting trees) estimates were used as indicators to analyze the effects of planting and harvesting regimes on forests in the region. The results showed that the following: (1) Increased planting intensity, although augmenting the coverage of P. koraiensis, was accompanied by decreases in planting efficiency and forest diversity. (2) While selective harvesting could increase forest diversity, the abrupt increase of early succession species accompanying this method merits attention. (3) Stimulating rapid forest succession may not be a good management strategy, since the climax species would crowd out other species which are likely more adapted to future climatic conditions in the long run. In light of the above, we suggest a combination of 30% planting intensity with selective harvesting of 50% and 70% of primary and secondary timber species, respectively, as the most effective management regime in this area. In the long run this would accelerate the ultimate dominance of P. koraiensis in the forest via a more effective rate of planting, while maintaining a higher degree of forest diversity. These results are particularly useful for forest managers constrained by limited financial and labor resources who must deal with conflicts between forest harvesting and restoration. PMID:22723930

  16. The Forest, The Fly, and the Virus?

    NASA Technical Reports Server (NTRS)

    Tucker, Compton J.; Pinzon, Jorge E.; Wilson, James M.

    2003-01-01

    All known outbreaks of Ebola have been linked to tropical forests. We undertook a study of environmental conditions associated with Ebola hemorrhagic fever after preliminary reports strongly suggested that simultaneous outbreaks occurred, during two limited time periods in the 1970s and 1990s, immediately following sudden transitions between dry and wet seasons.

  17. Phylobetadiversity among forest types in the Brazilian Atlantic Forest complex.

    PubMed

    Duarte, Leandro Da Silva; Bergamin, Rodrigo Scarton; Marcilio-Silva, Vinícius; Seger, Guilherme Dubal Dos Santos; Marques, Márcia Cristina Mendes

    2014-01-01

    Phylobetadiversity is defined as the phylogenetic resemblance between communities or biomes. Analyzing phylobetadiversity patterns among different vegetation physiognomies within a single biome is crucial to understand the historical affinities between them. Based on the widely accepted idea that different forest physiognomies within the Southern Brazilian Atlantic Forest constitute different facies of a single biome, we hypothesize that more recent phylogenetic nodes should drive phylobetadiversity gradients between the different forest types within the Atlantic Forest, as the phylogenetic divergence among those forest types is biogeographically recent. We compiled information from 206 checklists describing the occurrence of shrub/tree species across three different forest physiognomies within the Southern Brazilian Atlantic Forest (Dense, Mixed and Seasonal forests). We analyzed intra-site phylogenetic structure (phylogenetic diversity, net relatedness index and nearest taxon index) and phylobetadiversity between plots located at different forest types, using five different methods differing in sensitivity to either basal or terminal nodes (phylogenetic fuzzy weighting, COMDIST, COMDISTNT, UniFrac and Rao's H). Mixed forests showed higher phylogenetic diversity and overdispersion than the other forest types. Furthermore, all forest types differed from each other in relation phylobetadiversity patterns, particularly when phylobetadiversity methods more sensitive to terminal nodes were employed. Mixed forests tended to show higher phylogenetic differentiation to Dense and Seasonal forests than these latter from each other. The higher phylogenetic diversity and phylobetadiversity levels found in Mixed forests when compared to the others likely result from the biogeographical origin of several taxa occurring in these forests. On one hand, Mixed forests shelter several temperate taxa, like the conifers Araucaria and Podocarpus. On the other hand, tropical groups, like

  18. 78 FR 23903 - Forest Service

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-23

    ... Forest Service Dixie Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice of meeting... recommendations to the Forest Service concerning projects and funding consistent with Title II of the Act. The meeting is open to the public. The purpose of the meeting is to review proposals for forest projects...

  19. Using Our National Forests Wisely.

    ERIC Educational Resources Information Center

    Feuchter, Roy

    1987-01-01

    Lists nine steps camps can follow to insure successful use of national forests. Steps are identifying national forest resources; matching expectations with the right setting; using recreation opportunity guides; planning for safety; practicing forest etiquette; practicing fire prevention; knowing the forest environment; participating in volunteer…

  20. Trading forest carbon - OSU

    EPA Science Inventory

    Issues associate with trading carbon sequestered in forests are discussed. Scientific uncertainties associated with carbon measurement are discussed with respect to proposed accounting procedures. Major issues include: (1) Establishing baselines. (2) Determining additivity from f...

  1. Forest Fire Ecology.

    ERIC Educational Resources Information Center

    Zucca, Carol; And Others

    1995-01-01

    Presents a model that integrates high school science with the needs of the local scientific community. Describes how a high school ecology class conducted scientific research in fire ecology that benefited the students and a state park forest ecologist. (MKR)

  2. Carbon density and distribution of six Chinese temperate forests.

    PubMed

    Zhang, QuanZhi; Wang, ChuanKuan

    2010-07-01

    Quantifying forest carbon (C) storage and distribution is important for forest C cycling studies and terrestrial ecosystem modeling. Forest inventory and allometric approaches were used to measure C density and allocation in six representative temperate forests of similar stand age (42-59 years old) and growing under the same climate in northeastern China. The forests were an aspen-birch forest, a hardwood forest, a Korean pine plantation, a Dahurian larch plantation, a mixed deciduous forest, and a Mongolian oak forest. There were no significant differences in the C densities of ecosystem components (except for detritus) although the six forests had varying vegetation compositions and site conditions. However, the differences were significant when the C pools were normalized against stand basal area. The total ecosystem C density varied from 186.9 tC hm(-2) to 349.2 tC hm(-2) across the forests. The C densities of vegetation, detritus, and soil ranged from 86.3-122.7 tC hm(-2), 6.5-10.5 tC hm(-2), and 93.7-220.1 tC hm(-2), respectively, which accounted for 39.7% +/- 7.1% (mean +/- SD), 3.3% +/- 1.1%, and 57.0% +/- 7.9% of the total C densities, respectively. The overstory C pool accounted for > 99% of the total vegetation C pool. The foliage biomass, small root (diameter < 5mm) biomass, root-shoot ratio, and small root to foliage biomass ratio varied from 2.08-4.72 tC hm(-2), 0.95-3.24 tC hm(-2), 22.0%-28.3%, and 34.5%-122.2%, respectively. The Korean pine plantation had the lowest foliage production efficiency (total biomass/foliage biomass: 22.6 g g(-1)) among the six forests, while the Dahurian larch plantation had the highest small root production efficiency (total biomass/small root biomass: 124.7 g g(-1)). The small root C density decreased with soil depth for all forests except for the Mongolian oak forest, in which the small roots tended to be vertically distributed downwards. The C density of coarse woody debris was significantly less in the two

  3. Carbon density and distribution of six Chinese temperate forests.

    PubMed

    Zhang, QuanZhi; Wang, ChuanKuan

    2010-07-01

    Quantifying forest carbon (C) storage and distribution is important for forest C cycling studies and terrestrial ecosystem modeling. Forest inventory and allometric approaches were used to measure C density and allocation in six representative temperate forests of similar stand age (42-59 years old) and growing under the same climate in northeastern China. The forests were an aspen-birch forest, a hardwood forest, a Korean pine plantation, a Dahurian larch plantation, a mixed deciduous forest, and a Mongolian oak forest. There were no significant differences in the C densities of ecosystem components (except for detritus) although the six forests had varying vegetation compositions and site conditions. However, the differences were significant when the C pools were normalized against stand basal area. The total ecosystem C density varied from 186.9 tC hm(-2) to 349.2 tC hm(-2) across the forests. The C densities of vegetation, detritus, and soil ranged from 86.3-122.7 tC hm(-2), 6.5-10.5 tC hm(-2), and 93.7-220.1 tC hm(-2), respectively, which accounted for 39.7% +/- 7.1% (mean +/- SD), 3.3% +/- 1.1%, and 57.0% +/- 7.9% of the total C densities, respectively. The overstory C pool accounted for > 99% of the total vegetation C pool. The foliage biomass, small root (diameter < 5mm) biomass, root-shoot ratio, and small root to foliage biomass ratio varied from 2.08-4.72 tC hm(-2), 0.95-3.24 tC hm(-2), 22.0%-28.3%, and 34.5%-122.2%, respectively. The Korean pine plantation had the lowest foliage production efficiency (total biomass/foliage biomass: 22.6 g g(-1)) among the six forests, while the Dahurian larch plantation had the highest small root production efficiency (total biomass/small root biomass: 124.7 g g(-1)). The small root C density decreased with soil depth for all forests except for the Mongolian oak forest, in which the small roots tended to be vertically distributed downwards. The C density of coarse woody debris was significantly less in the two

  4. Effects of tropical montane forest disturbance on epiphytic macrolichens.

    PubMed

    Benítez, Angel; Prieto, María; González, Yadira; Aragón, Gregorio

    2012-12-15

    The high diversity of epiphytes typical of undisturbed montane tropical forests has been negatively affected by continuous deforestation and forest conversion to secondary vegetation. Macrolichens are an important component of these epiphytes. Because their physiology is strongly coupled to humidity and solar radiation, we hypothesized that microclimatic changes derived from forest clearing and logging can affect the diversity of these poikilohydric organisms. In southern Ecuador, we examined three types of forests according to a disturbance gradient (primary forests, secondary forests, and monospecific forests of Alnus acuminata) for the presence/absence and coverage of epiphytic macrolichens that we identified on 240 trees. We found that total richness tended to decrease when the range of the disturbance increased. The impoverishment was particularly drastic for "shade-adapted lichens", while the richness of "heliophytic lichens" increased in the drier conditions of secondary growth. Epiphytic composition also differed significantly among the three types of forests, and the similarity decreased when the range of the disturbance was greater. We concluded that a span of 40 years of recovery by secondary vegetation was not enough to regenerate the diversity of epiphytic macrolichens that was lost due to forest disturbances. PMID:23137982

  5. Monitoring the health of a forest: A Canadian approach.

    PubMed

    Addison, P A

    1989-04-01

    In Canada, acid rain is the generic term encompassing all forms of air pollution - wet and dry deposition, gaseous pollutant concentrations, and airborne particulates. It was because these pollutants, alone or in combination, may directly or indirectly affect the heath of Canada's forests, that in 1984, the Canadian Forestry Service initiated a national forest monitoring program (Acid Rain National Early Warning System or ARNEWS).Research studies on pollutant effects of the past 15-20 years have demonstrated that it is not possible to define specific symptoms of acid rain or mixtures of pollutants on native tree species or specific responses of the forest ecosystem. Consequently, ARNEWS monitored incipient acid rain effects by determining the forest's state of health rather than by concentrating on specific pollutant responses.The detection system entails experienced insect and disease survey forest rangers assessing both specific plots and the forest as a whole for extraordinary forest damage. The techniques used include mensurational and symptomatological measurements as well as evaluation of stands for damage from natural and anthropogenic causes. Critical also to the system was the capability of the Canadian Forestry Service to support the detection system with research staff who could carry out studies to explain any abnormalities in forest condition detected during the annual surveys. The ultimate outcome of the monitoring system if unexplained forest damage is detected is a research project on possible causes.

  6. Airborne forest fire research

    NASA Technical Reports Server (NTRS)

    Mattingly, G. S.

    1974-01-01

    The research relating to airborne fire fighting systems is reviewed to provide NASA/Langley Research Center with current information on the use of aircraft in forest fire operations, and to identify research requirements for future operations. A literature survey, interview of forest fire service personnel, analysis and synthesis of data from research reports and independent conclusions, and recommendations for future NASA-LRC programs are included.

  7. Forests of Mexico

    SciTech Connect

    Cairns, M.A.; Dirzo, R.; Zadroga, F.

    1995-07-01

    Forest of Mexico as elsewhere provide essential goods and services for both local citizens and the international community. Benefits include climate regulation, biodiversity, and wood and nonwood products for local consumption and economic activity. Deforestation is a matter of great environmental and economic concern. This article assesses rates of deforestation, the present status of forest in Mexico, and the major factors responsible for deforestation in the tropical southeastern region.

  8. A Project to Map and Monitor Baldcypress Forests in Coastal Louisiana, Using Landsat, MODIS, and ASTER Satellite Data

    NASA Technical Reports Server (NTRS)

    Spruce, Joseph; Sader, Steven; Smoot, James

    2012-01-01

    Cypress swamp forests of Louisiana offer many important ecological and economic benefits: wildlife habitat, forest products, storm buffers, water quality, and recreation. Such forests are also threatened by multiple factors: subsidence, salt water intrusion, sea level rise, persistent flooding, hydrologic modification, hurricanes, insect and nutria damage, timber harvesting, and land use conversion. Unfortunately, there are many information gaps regarding the type, location, extent, and condition of these forests. Better more up to date swamp forest mapping products are needed to aid coastal forest conservation and restoration work (e.g., through the Coastal Forest Conservation Initiative or CFCI). In response, a collaborative project was initiated to develop, test and demonstrate cypress swamp forest mapping products, using NASA supported Landsat, ASTER, and MODIS satellite data. Research Objectives are: Develop, test, and demonstrate use of Landsat and ASTER data for computing new cypress forest classification products and Landsat, ASTER, and MODIS satellite data for detecting and monitoring swamp forest change

  9. The Frequency and Fate of Understory Forest Fires in Amazonia

    NASA Astrophysics Data System (ADS)

    Morton, D. C.; le page, Y.; Wang, D.; Chen, Y.; Randerson, J. T.; Collatz, G. J.; Giglio, L.; Hurtt, G. C.; DeFries, R. S.

    2012-12-01

    Fires for deforestation or agricultural management frequently escape their intended boundaries and burn standing Amazon forests. The extent and frequency of understory forest fires are critical to assess forest carbon emissions and the long-term legacy of understory fires in Amazonia. Patterns of understory fire activity under current climate conditions also offer a blueprint for potential changes in Amazon forests under scenarios of future climate and land use. Here, we estimated of the extent and frequency of understory forest fires for the entire arc of deforestation in southern Amazonia using a time series of annual Moderate Resolution Imaging Spectroradiometer (MODIS) data. Understory forest fires burned more than 80,000 km2 during 1999-2010. Fires were widespread along the southern and eastern extents of Amazon forests during the four years with highest fire activity (1999, 2005, 2007, 2010). The interannual variability in understory fires offered new insights into fire-climate dynamics in Amazonia over a range of temporal scales, based on the combination of burned area, MODIS active fire detections, and reanalysis climate data. Initial fire exposure reduces aboveground carbon stocks, and frequent fires are one possible mechanism for long-term changes the structure of Amazon forests. Repeated burning was concentrated in southeastern Amazonia, and >95% of all repeated fires occurred in the Brazilian states of Mato Grosso and Pará. Forests that burned two or more times during this period accounted for 16% of understory fire activity. Finally, deforestation of burned forests was rare, suggesting that forest degradation from understory fires was an independent source of carbon emissions during this period. Modeling the time scales of carbon loss and recovery in burned forests is therefore critical to estimate the net carbon emissions from these fires. The results of this study suggest that understory fires operate as a large-scale edge effect in Amazonia, as

  10. Optical characterization of carbon nanotube forests

    NASA Astrophysics Data System (ADS)

    Wood, Brian D.

    Carbon nanotube forests are vertically grown tubular formations of graphene. Samples were grown with an injection chemical vapor deposition method on substrates of silicon with various deposited layers and bare fused silica. The morphology of the forest is characterized by the height, density, and presence of defects. Total diffuse reflectance and transmittance measurements were taken in the 2-16 ?m spectral range and correlated to the forest's specific morphology. From these correlations, the conditions necessary to maximize the absorption of the forest were found and exploited to cater sample growth for specific substrates to make ideal absorbers. From the transmittance data, the absorption coefficient is found via Beer-Lambert's Law and also correlated to sample morphology, giving us an indication of the height of the forest needed for ideal absorption. Two models were used to attempt to reproduce the experimental absorption coefficient: an effective medium theory using a Maxwell Garnett approximation and by treating the carbon nanotube forest as an effective cylindrical waveguide with walls of graphite. Each model leads to a set of fitting parameters providing a better physical understanding of the forests. It was found that the effective medium theory gave results loosely corroborated with electron microscopy, but had trouble fitting the experimental data, and the index of refraction it provides does not behave like a unified medium. The waveguide model fits the data well, but it requires more experimental evidence to be more conclusive. The theoretical models need more work, but fabrication of ideal absorbers has been achieved on various substrates providing framework for their usage in radiometry and spectroscopy.

  11. Restoration of biogeochemical function in mangrove forests

    USGS Publications Warehouse

    McKee, K.L.; Faulkner, P.L.

    2000-01-01

    Forest structure of mangrove restoration sites (6 and 14 years old) at two locations (Henderson Creek [HC] and Windstar [WS]) in southwest Florida differed from that of mixed-basin forests (>50 years old) with which they were once contiguous. However, the younger site (HC) was typical of natural, developing forests, whereas the older site (WS) was less well developed with low structural complexity. More stressful physicochemical conditions resulting from incomplete tidal flushing (elevated salinity) and variable topography (waterlogging) apparently affected plant survival and growth at the WS restoration site. Lower leaf fall and root production rates at the WS restoration site, compared with that at HC were partly attributable to differences in hydroedaphic conditions and structural development. However, leaf and root inputs at each restoration site were not significantly different from that in reference forests within the same physiographic setting. Macrofaunal consumption of tethered leaves also did not differ with site history, but was dramatically higher at HC compared with WS, reflecting local variation in leaf litter processing rates, primarily by snails (Melampus coffeus). Degradation of leaves and roots in mesh bags was slow overall at restoration sites, however, particularly at WS where aerobic decomposition may have been more limited. These findings indicate that local or regional factors such as salinity regime act together with site history to control primary production and turnover rates of organic matter in restoration sites. Species differences in senescent leaf nitrogen content and degradation rates further suggest that restoration sites dominated by Laguncularia racemosa and Rhizophora mangle should exhibit slower recycling of nutrients compared with natural basin forests where Avicennia germinans is more abundant. Structural development and biogeochemical functioning of restored mangrove forests thus depend on a number of factors, but site

  12. Drivers of forest cover dynamics in smallholder farming systems: the case of northwestern Vietnam.

    PubMed

    Jadin, Isaline; Vanacker, Veerle; Hoang, Huong Thi Thu

    2013-04-01

    The national-scale forest recovery of Vietnam started in the early 1990s and is associated with a shift from net deforestation to net reforestation. Large disparities in forest cover dynamics are, however, observed at the local scale. This study aims to unravel the mechanisms driving forest cover change for a mountainous region located in northwest Vietnam. Statistical analyses were used to explore the association between forest cover change and household characteristics. In Sa Pa district, deforestation rates are decreasing, but forest degradation continues at similar rates. Deforestation is not necessarily associated with impoverished ethnic communities or high levels of subsistence farming, and the largest forest cover dynamics are found in villages with the best socio-economic conditions. Our empirical study does not provide strong evidence of a dominant role of agriculture in forest cover dynamics. It shows that empirical studies on local-scale forest dynamics remain important to unravel the complexity of human-environment interactions. PMID:23001944

  13. Drivers of forest cover dynamics in smallholder farming systems: the case of northwestern Vietnam.

    PubMed

    Jadin, Isaline; Vanacker, Veerle; Hoang, Huong Thi Thu

    2013-04-01

    The national-scale forest recovery of Vietnam started in the early 1990s and is associated with a shift from net deforestation to net reforestation. Large disparities in forest cover dynamics are, however, observed at the local scale. This study aims to unravel the mechanisms driving forest cover change for a mountainous region located in northwest Vietnam. Statistical analyses were used to explore the association between forest cover change and household characteristics. In Sa Pa district, deforestation rates are decreasing, but forest degradation continues at similar rates. Deforestation is not necessarily associated with impoverished ethnic communities or high levels of subsistence farming, and the largest forest cover dynamics are found in villages with the best socio-economic conditions. Our empirical study does not provide strong evidence of a dominant role of agriculture in forest cover dynamics. It shows that empirical studies on local-scale forest dynamics remain important to unravel the complexity of human-environment interactions.

  14. Understanding the impacts of forest fragmentation in the Southern Appalachian Mountains

    SciTech Connect

    Pearson, S.M.

    1993-06-01

    Southern Appalachian forests are rich in biological diversity. These forests contain many species adapted to conditions ranging from mesic coves to xeric ridges. The major plant communities include wetlands and balds as well as hardwood and coniferous forests. To understand the impacts of habitat fragmentation, the sensitivity of ecosystems, communities, and species to fragmentation must be determined. Recognizing the natural patterns of heterogeneity in these forest and the importance of this heterogeneity to ecological processes will promote our understanding of fragmentation. The impact of a specific forest use (economic development, forest harvesting, recreation) depends on the type of habitat modification.and the spatial extent and pattern of this use. Information on ecological processes, maps of natural communities, and projections about activities that modify forests are needed in order to implement management strategies that will minimize forest fragmentation.

  15. Evaluation on the coefficient and exponent of runoff energy in MUSLE in forest watersed of Korea

    NASA Astrophysics Data System (ADS)

    Kim, Jaehoon; Choi, Hyung Tae; Lim, Hong-geun

    2016-04-01

    MUSLE is one of evaluation method of erosion and has been widely applied various areas. However, the coefficient and exponent of runoff energy in MUSLE was developed from US areas, especially Nebraska and Texas areas. Thus, when these values are applied in Korean forest watershed they should be modified due to the difference conditions such as topography, forest type and slope. This study was carried out to examine the coefficient and exponent of runoff energy in MUSLE for small forest watershed in Korea. Peak discharge, runoff volume and sediment yield were measured in forest watershed and the coefficient and exponent of runoff energy were calculated to 0.002 and 0.81 respectively. These values were based on undisturbed forest watershed and could be larger in disturbed forest including forest management or forest fires.

  16. Comment on "radioactive fallout in the United States due to the Fukushima nuclear plant accident" by P. Thakur, S. Ballard and R. Nelson, J. Environ. Monit., 2012, 14, 1317-1324.

    PubMed

    Rose, Paula S

    2014-07-01

    The May 2012 paper "Radioactive fallout in the United States due to the Fukushima nuclear plant accident" (P. Thakur, S. Ballard and R. Nelson, J. Environ. Monit., 2012, 14, 1317-1324), does not address medical patient excreta as a source of (131)I (t1/2 = 8.04 d) to the environment. While (131)I is generated during fission reactions and may be released to the environment from nuclear power plants, nuclear weapons tests, nuclear fuel reprocessing and weapons production facilities, it is also produced for medical use. Iodine-131 administered to patients, excreted and discharged to sewer systems is readily measureable in sewage and the environment; the patient-to-sewage pathway is the only source of (131)I in many locations. PMID:24816906

  17. Comment on "radioactive fallout in the United States due to the Fukushima nuclear plant accident" by P. Thakur, S. Ballard and R. Nelson, J. Environ. Monit., 2012, 14, 1317-1324.

    PubMed

    Rose, Paula S

    2014-07-01

    The May 2012 paper "Radioactive fallout in the United States due to the Fukushima nuclear plant accident" (P. Thakur, S. Ballard and R. Nelson, J. Environ. Monit., 2012, 14, 1317-1324), does not address medical patient excreta as a source of (131)I (t1/2 = 8.04 d) to the environment. While (131)I is generated during fission reactions and may be released to the environment from nuclear power plants, nuclear weapons tests, nuclear fuel reprocessing and weapons production facilities, it is also produced for medical use. Iodine-131 administered to patients, excreted and discharged to sewer systems is readily measureable in sewage and the environment; the patient-to-sewage pathway is the only source of (131)I in many locations.

  18. Boreal forest anomalies in the Yukon River Basin

    NASA Astrophysics Data System (ADS)

    Wylie, B. K.; Rover, J. A.; Murnahan, K.; Long, J.; Tieszen, L. L.; Brisco, B.

    2010-12-01

    Boreal forests are being impacted by climate change though productivity declines (browning), increased fire extents, frequencies, and intensities, more abundant insects, a thickening active layer, and projected increases in deciduous forest components. Quantification of the regional boreal forest impacts in the Yukon River Basin was achieved though remote sensing and productivity modeling which separated weather and non-weather interannual variations in boreal forest productivity. This “ecosystem performance anomaly” approach uses weather data and coarse resolution (250m) Normalized Difference Vegetation Index (NDVI) time series information from the Moderate Resolution Imaging Spectroradiometer (MODIS). Regression tree models developed from 2000-2005 data were robust when applied to 2006-08 data and predicted interannual growing season NDVI with good accuracy (R2=0.84) Confidence intervals of 90 percent were used to determine anomalous vegetation responses to weather conditions. Boreal forest areas which underperformed relative to weather conditions were often associated with fire events, likely reflecting early stages of succession. Areas which overperformed, relative to weather conditions, were associated with Aspen and Birch establishment after older fires and in mesic areas. Time series analysis of performance anomalies tracked non-linear temporal responses which corresponded well with fire burn dates and fire perimeters. Stressed and changing boreal systems can be identified with this approach and boreal forest productivity projections can be made from future climate projections. These data sets can focus field studies and remediation. Potential climate change refugia can be assessed relative to current stressed systems and future expected boreal forest productivity.

  19. Effects of Projected Transient Changes in Climate on Tennessee Forests

    SciTech Connect

    Dale, Virginia H; Tharp, M Lynn; Lannom, Karen O.; Hodges, Donald G.

    2010-01-01

    This study examines transient effects of projected climate change on the structure and species composition of forests in Tennessee. The climate change scenarios for 2030 and 2080 were provided by the National Center for Atmospheric Research (NCAR) from three General Circulation Models (GCMs) that simulate the range of potential climate conditions for the state. The precipitation and temperature projections from the three GCMs for 2030 and 2080 were related to changes in the ecoregions by using the monthly record of temperature and precipitation from 1980 to 1997 for each 1 km cell across the state as aggregated into the five ecological provinces. Temperatures are projected to increase in all ecological provinces in all months for all three GCMs for both 2030 and 2080. Precipitation patterns are more complex with one model projecting wetter summers and two models projecting drier summers. The forest ecosystem model LINKAGES was used to simulate conditions in forest stands for the five ecological provinces of Tennessee from 1989 to 2300. These model runs suggest there will be a change in tree diversity and species composition in all ecological provinces with the greatest changes occurring in the Southern Mixed Forest province. Most projections show a decline in total tree biomass followed by recovery as species replacement occurs in stands. The changes in forest biomass and composition, as simulated in this study, are likely to have implications on forest economy, tourism, understory conditions, wildlife habitat, mast provisioning, and other services provided by forest systems.

  20. Forest successional stage affects the cortical secondary chemistry of three old forest lichens.

    PubMed

    Nybakken, Line; Asplund, Johan; Solhaug, Knut Asbjørn; Gauslaa, Yngvar

    2007-08-01

    Three epiphytic old forest lichens (Usnea longissima, Pseudocyphellaria crocata, and Lobaria pulmonaria) were transplanted along a natural shade-sun gradient comprising three successional stages in boreal spruce forests (dense young forest, open old forest, and clear-cut) for one summer. After harvest, extractable secondary compounds were analyzed by high-performance liquid chromatography, and the brown pigmentation in melanic species was quantified by reflectance measurements. Cortical compounds in all species increased from shady young forests to exposed clear-cuts. Usnic acid, the major cortical, secondary compound in U. longissima, showed consistently higher concentration in the clear-cut than in the two forested stands. Pseudocyphellaria crocata and L. pulmonaria, lacking extractable secondary compounds in the cortex, significantly increased their amounts of cortical melanins in well-lit stands. The medullary compounds showed more complex responses. Many were not influenced by environmental conditions during the transplantation, whereas the majority of those that responded showed the lowest concentration in clear-cut transplants. Only a few medullary compounds showed the highest concentration in the clear-cut, and at a low level of significance. The synthesis of UV-B-absorbing usnic acid and melanins seems to be part of an acclimation to increased light exposure. The medullary compounds in studied species barely function as solar screens despite their strong UV-B absorbance.

  1. Using the ratio of optical channels in satellite image decoding in monitoring biodiversity of boreal forests

    NASA Astrophysics Data System (ADS)

    Rozhkov, Yurj P.; Kondakova, Maria Y.

    2013-10-01

    The study contains the results of forest monitoring at three levels: the forests condition assessment at the time of recording or mapping for this indicator, the seasonal changes assessment in the forests condition, mainly during the vegetation period and the evaluation of long-term changes in the values of the studied parameters on the example of the forests recovery after a fire. The use of two indices - NDVI and Image Difference in the boreal forests monitoring is treated. NDVI assesses the state of plant biomass and its productivity. The rate of Image Difference characterizes the optical density and allows estimate the density of the forest stand. In addition, by identifying Image Difference on summer and autumn pictures it can makes a distinction of different wood species, to divide forest areas, which consist of deciduous and coniferous species and larch which shedded needles at the end of the vegetation period. Therefore, it is possible to differentiate the pine, cedar, spruce forests on the one side and birch, larch, alder on the other side. The optical density of the forest decreases after the needles- and the leaf sheddings. Using the index Image Difference in estimates of long-term changes of the forest stand shows the trend of changes of the forest density and the tree species composition. The results of the analysis of the recovery process of the forest after a fire in the period from 1995 to 2009 showed how shoots of birch, larch and pine recover wastelands.

  2. Carbon sequestration in managed temperate coniferous forests under climate change

    NASA Astrophysics Data System (ADS)

    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.

  3. Variation in mangrove forest structure and sediment characteristics in Bocas del Toro, Panama

    USGS Publications Warehouse

    Lovelock, C.E.; Feller, Ilka C.; McKee, K.L.; Thompson, R.

    2005-01-01

    Mangrove forest structure and sediment characteristics were examined in the extensive mangroves of Bocas del Toro, Republic of Panama. Forest structure was characterized to determine if spatial vegetation patterns were repeated over the Bocas del Toro landscape. Using a series of permanent plots and transects we found that the forests of Bocas del Toro were dominated by Rhizophora mangle with very few individuals of Avicennia germinans and Laguncularia racemosa. Despite this low species diversity, there was large variation in forest structure and in edaphic conditions (salinity, concentration of available phosphorus, Eh and sulphide concentration). Aboveground biomass varied 20-fold, from 6.8 Mg ha-1 in dwarf forests to 194.3 Mg ha-1 in the forests fringing the land. But variation in forest structure was predictable across the intertidal zone. There was a strong tree height gradient from seaward fringe (mean tree height 3.9 m), decreasing in stature in the interior dwarf forests (mean tree height 0.7 m), and increasing in stature in forests adjacent to the terrestrial forest (mean tree height 4.1 m). The predictable variation in forest structure emerges due to the complex interactions among edaphic and plant factors. Identifying predictable patterns in forest structure will aid in scaling up the ecosystem services provided by mangrove forests in coastal landscapes. Copyright 2005 College of Arts and Sciences.

  4. Hurricane Katrina-induced forest damage in relation to ecological factors at landscape scale.

    PubMed

    Wang, Fugui; Xu, Y Jun

    2009-09-01

    Forest stand stability to strong winds such as hurricanes has been found to be associated with a number of forest, soil and topography factors. In this study, through applying geographic information system (GIS) and logit regression, we assessed effects of forest characteristics and site conditions on pattern, severity and probability of Hurricane Katrina disturbance to forests in the Lower Pearl River Valley, USA. The factors included forest type, forest coverage, stand density, soil great group, elevation, slope, aspect, and stream buffer zone. Results showed that Hurricane Katrina damaged 60% of the total forested land in the region. The distribution and intensity of the hurricane disturbance varied across the landscape, with the bottomland hardwood forests on river floodplains most severely affected. All these factors had a variety of effects on vulnerability of the forests to the hurricane disturbance and thereby spatial patterns of the disturbance. Soil groups and stand factors including forest types, forest coverage and stand density contributed to 85% of accuracy in modeling the probability of the hurricane disturbance to forests in this region. Besides assessment of Katrina's damage, this study elucidates the great usefulness of remote sensing and GIS techniques combined with statistics modeling in assessment of large-scale risks of hurricane damage to coastal forests.

  5. A simple and effective method for detecting and quantifying forest disturbances and regeneration using Landsat imagery

    NASA Astrophysics Data System (ADS)

    Jin, S.; Yang, L.; Danielson, P.; Homer, C.; Fry, J.

    2012-12-01

    Disturbances of any size and magnitude of intensity, whether natural or human-caused, change existing forest conditions and initiate succession to create dynamic and new ecological communities. Effective management of these forest resources, both public and private, requires reliable and timely information about their status and trends. As part of the National Land Cover Database, we have developed a focused change detection method using Landsat imagery to improve the efficiency and effectiveness of existing forest change monitoring capabilities. The Normalized Burn Ratio (NBR) derived from Landsat imagery has been widely used for monitoring fire disturbance, and the Normalized Difference Vegetation Index (NDVI) has been extensively used for indicating the vegetation biomass, or health and vitality status. By integrating these two indices derived from imagery acquired from two-date Landsat images within a growing season, a model was developed to intelligently map the location and quantify the magnitude of forest disturbance and regeneration processes. The model has been tested on four image pairs from different forest regions (Northeast, Southeast, Northwest, and Southwest) of the United States. Initial results showed that the method can map high intensity forest disturbance such as forest harvest and forest fire with high accuracy; it is also sensitive to subtle changes such as forest regeneration, forest commercial thinning, and forest degradation caused by insect damage. The model is simple, effective, and applicable to other regions with forest cover. The approach can provide critical and objective change information on status and trends on forested land for management planning purposes.

  6. Mapping diverse forest cover with multipolarization airborne radar

    NASA Technical Reports Server (NTRS)

    Ford, J. P.; Wickland, D. E.; Sharitz, R. R.

    1985-01-01

    Imaging radar backscatter in continuously forested areas contains information about the forest canopy; it also contains data about topography, landforms, and terrain texture. For purposes of radar image interpretation and geologic mapping researchers were interested in identifying and separating forest canopy effects from geologic or geomorphic effects on radar images. The objectives of this investigation was to evaluate forest canopy variables in multipolarization radar images under conditions where geologic and topographic variables are at a minimum. A subsidiary objective was to compare the discriminatory capabilities of the radar images with corresponding optical images of similar spatial resolution. It appears that the multipolarization images discriminate variation in tree density, but no evidence was found for discrimination between evergreen and deciduous forest types.

  7. Differences in carbon uptake and water use between managed and unmanaged European beech forests

    NASA Astrophysics Data System (ADS)

    Herbst, M.; Mund, M.; Knohl, A.

    2013-12-01

    Based on 23 site-years of eddy covariance measurements made above a managed beech forest and a nearby unmanaged, old-growth forest in central Germany, a comparative analysis of the carbon and energy fluxes of the two forests was carried out. Both forests are located at similar altitude and they face similar meteorological conditions. They are also similar with respect to canopy height (37 m) and mean tree age (120 years). The managed beech forest is a monospecific, even-aged stand with species-rich ground vegetation and a leaf area index of about 4, whereas the old-growth forest is beech-dominated but interspersed with ash and sycamore trees. It has a multi-layer canopy consisting of trees of various ages ranging from 0 to 260 years and its leaf area index is about 5. On average the two forests did not differ significantly in annual net carbon uptake (508 and 483 g C m-2 a-1 for the managed and the unmanaged forest, respectively), however the managed forest showed a much larger interannual variability in gross primary production than the unmanaged forest did. This trend agreed well with independent dendrometric measurements made in both forests. In contrast, ecosystem respiration did neither vary significantly between the two forests nor between different years. The total annual evapotranspiration was slightly higher at the unmanaged forest site (549 mm a-1 compared to 504 mm a-1 at the managed site), which was probably due to a higher interception loss from the denser canopy in the unmanaged forest. We discuss whether the conclusion can be drawn from this case study that common forest management activities improve the water use efficiency of European beech forests but make them more vulnerable against extreme meteorological conditions such as, for example, summer heat waves or late frosts in spring.

  8. Old-growth definition for Red River bottom forests in the eastern United States. Forest Service general technical report

    SciTech Connect

    Shear, T.; Young, M.; Kellison, R.

    1997-05-01

    Our goal was to develop a description of old-growth red river bottom forests of the Southeastern United States. We compared the characteristics of forests described in the scientific literature and forests we examined to various published criteria for old-growth condition. Because red rivers are a relatively new landscape feature (most < 250 years old, resulting from human-induced soil erosion) and because dramatic changes to their floodplains continue to occur, we do not believe that any old-growth red river forests exist. All the stands along these rivers present at European settlement have been cut and/or otherwise severely altered. In the dynamic landscape after settlement, there have been no opportunities for new old-growth forests to develop. Stands older than 50 to 60 years are rare. Therefore, we propose a stand condition called older growth and list the characteristics. With time and stable site conditions, we believe that old-growth and red river forests can develop from older-growth forests.

  9. Forest herb layer response to long-term light deficit along a forest developmental series

    NASA Astrophysics Data System (ADS)

    Plue, J.; Van Gils, B.; De Schrijver, A.; Peppler-Lisbach, C.; Verheyen, K.; Hermy, M.

    2013-11-01

    Temperate deciduous forest communities are slow-changing systems, with herbaceous understorey communities displaying a delayed response to overstorey canopy and light dynamics. While light availability constrains herbaceous understorey diversity and composition in space and time, its response in the long-term absence of light has seldom been quantified, particularly as it is often confounded by covariation in soil conditions. We studied a developmental high-forest series in two widespread NW-European temperate deciduous forest communities with different dominant canopy tree species: Stellario-Carpinetum (Oak-hornbeam canopy) and Milio-Fagetum (Beech canopy). All plots had soil conditions which were not significantly different, enabling investigation into the direct effects of the long-term absence of light on the herbaceous understorey, disentangled from the confounding effects of soil variation. Plant species richness measures declined with canopy cover continuity in the herb layer of the oak-hornbeam stands, whereas richness in the herb layer of the beech stands displayed a unimodal response. Nonetheless, in both plant communities, species richness and closed-forest species richness were negatively affected by the extended absence of light in stands with the longest period of continuous canopy cover. The long-term limitation or decline in quantitative and qualitative light availability as a result of extended periods of canopy cover was shown to be the primary driver behind losses in alpha-diversity, community composition turn-over and individual species dynamics. Heliophilous species were lost from both communities, while closed-forest species also declined, as a direct consequence of the prolonged period without ample light on the forest floor. This study demonstrates how the herb layer is affected by the absence of light on the forest floor mediated by long periods of continuous canopy cover. Despite different temporal responses in herb layer richness and

  10. Soil moisture in sessile oak forest gaps

    NASA Astrophysics Data System (ADS)

    Zagyvainé Kiss, Katalin Anita; Vastag, Viktor; Gribovszki, Zoltán; Kalicz, Péter

    2015-04-01

    By social demands are being promoted the aspects of the natural forest management. In forestry the concept of continuous forest has been an accepted principle also in Hungary since the last decades. The first step from even-aged stand to continuous forest can be the forest regeneration based on gap cutting, so small openings are formed in a forest due to forestry interventions. This new stand structure modifies the hydrological conditions for the regrowth. Without canopy and due to the decreasing amounts of forest litter the interception is less significant so higher amount of precipitation reaching the soil. This research focuses on soil moisture patterns caused by gaps. The spatio-temporal variability of soil water content is measured in gaps and in surrounding sessile oak (Quercus petraea) forest stand. Soil moisture was determined with manual soil moisture meter which use Time-Domain Reflectometry (TDR) technology. The three different sizes gaps (G1: 10m, G2: 20m, G3: 30m) was opened next to Sopron on the Dalos Hill in Hungary. First, it was determined that there is difference in soil moisture between forest stand and gaps. Second, it was defined that how the gap size influences the soil moisture content. To explore the short term variability of soil moisture, two 24-hour (in growing season) and a 48-hour (in dormant season) field campaign were also performed in case of the medium-sized G2 gap along two/four transects. Subdaily changes of soil moisture were performed. The measured soil moisture pattern was compared with the radiation pattern. It was found that the non-illuminated areas were wetter and in the dormant season the subdaily changes cease. According to our measurements, in the gap there is more available water than under the forest stand due to the less evaporation and interception loss. Acknowledgements: The research was supported by TÁMOP-4.2.2.A-11/1/KONV-2012-0004 and AGRARKLIMA.2 VKSZ_12-1-2013-0034.

  11. Trends in nitrogen and phosphorus cycling are consistent and constrained during tropical secondary forest succession: is secondary forest young primary forest from a nutrient perspective?

    NASA Astrophysics Data System (ADS)

    Sullivan, B. W.; Nasto, M.; Alvarez-Clare, S.; Cole, R. J.; Reed, S.; Chazdon, R.; Davidson, E. A.; Cleveland, C. C.

    2015-12-01

    Extensive deforestation of tropical rainforest often leads to agricultural abandonment and secondary forest regeneration. The land area of secondary rainforest is soon likely to exceed that of primary forest, highlighting the importance of secondary tropical rainforest in the global carbon (C) cycle. Secondary forests often grow rapidly, but the role soil nutrients play in regulating secondary forest productivity remains unsettled. Consistent with biogeochemical theory, a landmark study from a set of sites in the Amazon Basin showed that secondary forests had low nitrogen (N) availability and relatively higher phosphorus (P) availability immediately after abandonment, but that as succession proceeded, N availability "recuperated" and there was relatively less P available. To address whether such changes in N and P availability during secondary forest growth are common, we reviewed 38 studies in lowland tropical rainforest that reported changes in 23 different metrics of N and P cycling during secondary succession. We calculated slopes (rates of change) during secondary succession for each metric in each study, and analyzed patterns in these rates of change. Significant trends during secondary succession were more evident in soils than in plants, but in most cases, the variability among studies was surprisingly low. Both soil N and P availability increased through succession, at least in surface soil. Such consistent changes imply substantial biogeochemical resilience of tropical forest soils in spite of differing land use histories and species compositions among studies. In most cases, slopes were similar whether primary forest was included in, or excluded from, our analysis, suggesting that secondary succession eventually leads to similar biogeochemical conditions as those found in primary forest. Our results suggesting consistent changes in N and P availability during succession provide a biogeochemical rationale for the conservation and restoration value of

  12. On the decline of ground lichen forests in the Swedish boreal landscape: Implications for reindeer husbandry and sustainable forest management.

    PubMed

    Sandström, Per; Cory, Neil; Svensson, Johan; Hedenås, Henrik; Jougda, Leif; Borchert, Nanna

    2016-05-01

    Lichens are a bottleneck resource for circumpolar populations of reindeer, and as such, for reindeer husbandry as an indigenous Sami land-use tradition in northern Sweden. This study uses ground lichen data and forest information collected within the Swedish National Forest Inventory since 1953, on the scale of northern Sweden. We found a 71 % decline in the area of lichen-abundant forests over the last 60 years. A decline was observed in all regions and age classes and especially coincided with a decrease of >60 year old, open pine forests, which was the primary explanatory factor in our model. The effects of reindeer numbers were inconclusive in explaining the decrease in lichen-abundant forest. The role that forestry has played in causing this decline can be debated, but forestry can have a significant role in reversing the trend and improving ground lichen conditions.

  13. On the decline of ground lichen forests in the Swedish boreal landscape: Implications for reindeer husbandry and sustainable forest management.

    PubMed

    Sandström, Per; Cory, Neil; Svensson, Johan; Hedenås, Henrik; Jougda, Leif; Borchert, Nanna

    2016-05-01

    Lichens are a bottleneck resource for circumpolar populations of reindeer, and as such, for reindeer husbandry as an indigenous Sami land-use tradition in northern Sweden. This study uses ground lichen data and forest information collected within the Swedish National Forest Inventory since 1953, on the scale of northern Sweden. We found a 71 % decline in the area of lichen-abundant forests over the last 60 years. A decline was observed in all regions and age classes and especially coincided with a decrease of >60 year old, open pine forests, which was the primary explanatory factor in our model. The effects of reindeer numbers were inconclusive in explaining the decrease in lichen-abundant forest. The role that forestry has played in causing this decline can be debated, but forestry can have a significant role in reversing the trend and improving ground lichen conditions. PMID:26754169

  14. The purpose of forests

    SciTech Connect

    Westoby, J.

    1987-01-01

    The writings and speeches in this book have been selected to illustrate Jack Westoby's contributions to international forestry over the last two decades and more, and to show something of the evolution of his thinking. The problems he addresses are ones central to international forest policy and to the proper social responsibilities of foresters. This paper covers the following topics: Part I is a selection of papers which Westoby wrote during the 1960s on forest industries and their part in propelling economic development. The papers of Part II explore the responsibilities and dilemmas of the forestry profession in deciding which, among conflicting interests, to serve. Part III develops and enlarges Westoby's ideas of what forestry should be about-which he earlier defined as making trees serve people.

  15. Forests as carbon sinks

    SciTech Connect

    Houghton, R.A.; Woodwell, R.M.

    1995-11-01

    When the nations of the world signed and later ratified the United Nations Framework Convention on Climate Change (FCCC), they accepted the difficult challenge of stabilizing the composition of the atmosphere with respect to the greenhouse gases (GHGs). Success will require a reduction in both use of fossil fuels and rates of deforestation. Forests have a large enough influence on the atmosphere that one of the options for stabilizing the concentrations of GHGs in the atmosphere includes the use of forests as a carbon sink through reforestation of large areas. We identify in this paper the potential and the limitations of such projects. We discuss the implications of four approaches in management of forests globally: (i) continued deforestation, (ii) halting deforestation, (iii) net reforestation including agroforestry, and (iv) substituting the use of wood fuels for fossil fuels.

  16. Forest Mitigation Strategy

    NASA Astrophysics Data System (ADS)

    Arcidiacono-Barsony, C.; Ciais, P.; Viovy, N.; Vuichard, N.; Friedlingstein, P.

    2011-01-01

    Deforestation is a major driver of climate change contributing ~ 12% of global anthropogenic CO2 atmospheric emissions. A climate mitigation mechanism called Reduction Emission from Deforestation and forest Degradation (REDD) has been developed to tackle emissions due to forest loss in developing countries. In light of the final document agreed at the 15th UN Conference of the Parties, REDD will be central in any post- 2012 climate agreement. Nonetheless, REDD's political, economical and scientific challenges should still be addressed. To aid the scientific community, a review of current and future deforestation estimates in terms of forest surface change, carbon density, and carbon flux has been prepared. In addition, current estimates of REDD mitigation potential and a simple case study have also been examined. Preliminary results are presented here.

  17. Boreal forests, aerosols and the impacts on clouds and climate.

    PubMed

    Spracklen, Dominick V; Bonn, Boris; Carslaw, Kenneth S

    2008-12-28

    Previous studies have concluded that boreal forests warm the climate because the cooling from storage of carbon in vegetation and soils is cancelled out by the warming due to the absorption of the Sun's heat by the dark forest canopy. However, these studies ignored the impacts of forests on atmospheric aerosol. We use a global atmospheric model to show that, through emission of organic vapours and the resulting condensational growth of newly formed particles, boreal forests double regional cloud condensation nuclei concentrations (from approx. 100 to approx. 200 cm(-3)). Using a simple radiative model, we estimate that the resulting change in cloud albedo causes a radiative forcing of between -1.8 and -6.7 W m(-2) of forest. This forcing may be sufficiently large to result in boreal forests having an overall cooling impact on climate. We propose that the combination of climate forcings related to boreal forests may result in an important global homeostasis. In cold climatic conditions, the snow-vegetation albedo effect dominates and boreal forests warm the climate, whereas in warmer climates they may emit sufficiently large amounts of organic vapour modifying cloud albedo and acting to cool climate.

  18. Sustained losses of bioavailable nitrogen from montane tropical forests

    NASA Astrophysics Data System (ADS)

    Brookshire, E. N. Jack; Hedin, Lars O.; Newbold, J. Denis; Sigman, Daniel M.; Jackson, John K.

    2012-02-01

    Tropical forests account for one third of terrestrial primary production and contribute significantly to the land carbon sink. The future of this sink relies critically on forest interactions with nutrient cycles. Humid montane tropical forests are often thought to be rich in phosphorus, but to contain low levels of bioavailable nitrogen. Here, we examine the concentration of dissolved nitrogen compounds and the isotopic composition of nitrate in streams in six well-characterized and phosphorus-rich montane forests in Costa Rica, and in 55 montane forests across Central America and the Caribbean, using data collected between 1990 and 2008. We found high levels of nitrate in these streams, indicative of large losses of bioavailable nitrogen from these forests. We detected no trend in the concentration and isotopic signature of nitrate over the measurement period, implying that high levels of export are neither recent nor episodic. An analysis of the oxygen isotopic signature of stream nitrate showed that exports are sourced from the plant-soil system, rather than from atmospheric deposition that bypasses forest biota. Our findings indicate that nitrogen-rich conditions can develop irrespective of phosphorus availability at the ecosystem scale. We suggest that nitrogen availability may not limit plant growth, or its response to increasing atmospheric carbon dioxide levels, in many montane tropical forests.

  19. Forest canopy gap distributions in the southern Peruvian Amazon.

    PubMed

    Asner, Gregory P; Kellner, James R; Kennedy-Bowdoin, Ty; Knapp, David E; Anderson, Christopher; Martin, Roberta E

    2013-01-01

    Canopy gaps express the time-integrated effects of tree failure and mortality as well as regrowth and succession in tropical forests. Quantifying the size and spatial distribution of canopy gaps is requisite to modeling forest functional processes ranging from carbon fluxes to species interactions and biological diversity. Using high-resolution airborne Light Detection and Ranging (LiDAR), we mapped and analyzed 5,877,937 static canopy gaps throughout 125,581 ha of lowland Amazonian forest in Peru. Our LiDAR sampling covered a wide range of forest physiognomies across contrasting geologic and topographic conditions, and on depositional floodplain and erosional terra firme substrates. We used the scaling exponent of the Zeta distribution (λ) as a metric to quantify and compare the negative relationship between canopy gap frequency and size across sites. Despite variable canopy height and forest type, values of λ were highly conservative (λ mean  = 1.83, s  = 0.09), and little variation was observed regionally among geologic substrates and forest types, or at the landscape level comparing depositional-floodplain and erosional terra firme landscapes. λ-values less than 2.0 indicate that these forests are subjected to large gaps that reset carbon stocks when they occur. Consistency of λ-values strongly suggests similarity in the mechanisms of canopy failure across a diverse array of lowland forests in southwestern Amazonia. PMID:23613748

  20. Forest Canopy Gap Distributions in the Southern Peruvian Amazon

    PubMed Central

    Asner, Gregory P.; Kellner, James R.; Kennedy-Bowdoin, Ty; Knapp, David E.; Anderson, Christopher; Martin, Roberta E.

    2013-01-01

    Canopy gaps express the time-integrated effects of tree failure and mortality as well as regrowth and succession in tropical forests. Quantifying the size and spatial distribution of canopy gaps is requisite to modeling forest functional processes ranging from carbon fluxes to species interactions and biological diversity. Using high-resolution airborne Light Detection and Ranging (LiDAR), we mapped and analyzed 5,877,937 static canopy gaps throughout 125,581 ha of lowland Amazonian forest in Peru. Our LiDAR sampling covered a wide range of forest physiognomies across contrasting geologic and topographic conditions, and on depositional floodplain and erosional terra firme substrates. We used the scaling exponent of the Zeta distribution (λ) as a metric to quantify and compare the negative relationship between canopy gap frequency and size across sites. Despite variable canopy height and forest type, values of λ were highly conservative (λ mean  = 1.83, s  = 0.09), and little variation was observed regionally among geologic substrates and forest types, or at the landscape level comparing depositional-floodplain and erosional terra firme landscapes. λ-values less than 2.0 indicate that these forests are subjected to large gaps that reset carbon stocks when they occur. Consistency of λ-values strongly suggests similarity in the mechanisms of canopy failure across a diverse array of lowland forests in southwestern Amazonia. PMID:23613748

  1. Estimation of forest parameters using airborne laser scanning data

    NASA Astrophysics Data System (ADS)

    Cohen, J.

    2015-12-01

    Methods for the estimation of forest characteristics by airborne laser scanning (ALS) data have been introduced by several authors. Tree height (TH) and canopy closure (CC) describing the forest properties can be used in forest, construction and industry applications, as well as research and decision making. The National Land Survey has been collecting ALS data from Finland since 2008 to generate a nationwide high resolution digital elevation model. Although this data has been collected in leaf-off conditions, it still has the potential to be utilized in forest mapping. A method where this data is used for the estimation of CC and TH in the boreal forest region is presented in this paper. Evaluation was conducted in eight test areas across Finland by comparing the results with corresponding Multi-Source National Forest Inventory (MS-NFI) datasets. The ALS based CC and TH maps were generally in a good agreement with the MS-NFI data. As expected, deciduous forests caused some underestimation in CC and TH, but the effect was not major in any of the test areas. The processing chain has been fully automated enabling fast generation of forest maps for different areas.

  2. Global Forest Area Trends Underestimate Threats from Forest Fragmentation

    EPA Science Inventory

    Forest loss and fragmentation of the remainder threaten the ecological attributes and functions which depend upon forests1. Forest interior area is particularly valued because it is relatively remote from human influence2, 3, 4, 5. Recent global assessments report declines in t...

  3. Perceptions about Forest Schools: Encouraging and Promoting Archimedes Forest Schools

    ERIC Educational Resources Information Center

    Nawaz, Haq; Blackwell, Sarah

    2014-01-01

    The aim of this study was to find out parents' and children's perception of outdoor learning programmes with specific reference to Archimedes Forest Schools, known as Forest Schools. A review of existing research showed that there had been no rigorous evaluation of perception of forest schools. The study was conducted in the UK and mixed…

  4. DRAINMOD-FOREST: Integrated Modeling of Hydrology, Soil Carbon and Nitrogen Dynamics, and Plant Growth for Drained Forests.

    PubMed

    Tian, Shiying; Youssef, Mohamed A; Skaggs, R Wayne; Amatya, Devendra M; Chescheir, G M

    2012-01-01

    We present a hybrid and stand-level forest ecosystem model, DRAINMOD-FOREST, for simulating the hydrology, carbon (C) and nitrogen (N) dynamics, and tree growth for drained forest lands under common silvicultural practices. The model was developed by linking DRAINMOD, the hydrological model, and DRAINMOD-N II, the soil C and N dynamics model, to a forest growth model, which was adapted mainly from the 3-PG model. The forest growth model estimates net primary production, C allocation, and litterfall using physiology-based methods regulated by air temperature, water deficit, stand age, and soil N conditions. The performance of the newly developed DRAINMOD-FOREST model was evaluated using a long-term (21-yr) data set collected from an artificially drained loblolly pine ( L.) plantation in eastern North Carolina, USA. Results indicated that the DRAINMOD-FOREST accurately predicted annual, monthly, and daily drainage, as indicated by Nash-Sutcliffe coefficients of 0.93, 0.87, and 0.75, respectively. The model also predicted annual net primary productivity and dynamics of leaf area index reasonably well. Predicted temporal changes in the organic matter pool on the forest floor and in forest soil were reasonable compared to published literature. Both predicted annual and monthly nitrate export were in good agreement with field measurements, as indicated by Nash-Sutcliffe coefficients above 0.89 and 0.79 for annual and monthly predictions, respectively. This application of DRAINMOD-FOREST demonstrated its capability for predicting hydrology and C and N dynamics in drained forests under limited silvicultural practices.

  5. Forest Pest Control. Manual 94.

    ERIC Educational Resources Information Center

    Missouri Univ., Columbia. Agricultural Experiment Station.

    This training manual provides information needed to meet the minimum EPA standards for certification as a commercial applicator of pesticides in forest pest control. The text discusses disease problems, insects, and herbicide use in both established forests and nurseries. (CS)

  6. Climate warming threatens semi-arid forests in Inner Asia

    NASA Astrophysics Data System (ADS)

    WU, X.

    2015-12-01

    A line of evidences reveal an increasing tree growth decline and tree mortality mainly attributable to climate warming and the warming-mediated changes in drought and other processes in many parts of world tropical, temperate and boreal forests. However, the growth responses to climate change of the widely distributed semi-arid forests are unclear. Here, we synthetically investigate the tree growth patterns during past decades and its interannual response to climate variations in Inner Asia combining the ground truth field survey and samplings, remote sensing observations and climate data. We identified a pervasive tree growth decline since mid-1990s in semi-arid forests in Inner Asia. The widely observed tree growth decline is dominantly attributable to warming-induced water stress during pre- and early growing season. Tree growth of semi-arid forests in Inner Asia is particularly susceptible to spring warming and has been suffering a prolonged growth limitation in recent decades due to spring warming-mediated water conditions. Additionally, we identified a much slower growth rate in younger trees and a lack of tree regeneration in these semi-arid forests. The widely observed forest growth reduction and lack of tree regeneration over semi-arid forests in Inner Asia could predictably exert great effects on forest structure, regionally/globally biophysical and biochemical processes and the feedbacks between biosphere and atmosphere. Notably, further increases in forest stress and tree mortality could be reasonably expected, especially in context of the increase frequency and severity of high temperature and heat waves and changes in forest disturbances, potentially driving the eventual regional loss of current semi-arid forests. Given the potential risks of climate induced forest dieback, increased management attention to adaptation options for enhancing forest resistance and resilience to projected climate stress can be expected. However, the functionally realistic

  7. Climate Warming Threatens Semi-arid Forests in Inner Asia

    NASA Astrophysics Data System (ADS)

    WU, X.; Liu, H.; Qi, Z.; Li, X.

    2014-12-01

    A line of evidences reveal an increasing tree growth decline and tree mortality mainly attributable to climate warming and the warming-mediated changes in drought and other processes (such as fire and insect dynamics) in many parts of world tropical, temperate and boreal forests. However, the growth responses to climate change of the widely distributed semi-arid forests are unclear. Here, we synthetically investigate the tree growth patterns during past decades and its interannual response to climate variations in Inner Asia combining the ground truth field survey and samplings, remote sensing observations and climate data. We identified a pervasive tree growth decline since mid-1990s in semi-arid forests in Inner Asia. The widely observed tree growth decline is dominantly attributable to warming-induced water stress during pre- and early growing season. Tree growth of semi-arid forests in Inner Asia is particularly susceptible to spring warming and has been suffering a prolonged growth limitation in recent decades due to spring warming-mediated water conditions. Additionally, we identified a much slower growth rate in younger trees and a lack of tree regeneration in these semi-arid forests. The widely observed forest growth reduction and lack of tree regeneration over semi-arid forests in Inner Asia could predictably exert great effects on forest structure, regionally/globally biophysical and biochemical processes and the feedbacks between biosphere and atmosphere. Notably, further increases in forest stress and tree mortality could be reasonably expected, especially in context of the increase frequency and severity of high temperature and heat waves and changes in forest disturbances, potentially driving the eventual regional loss of current semi-arid forests. Given the potential risks of climate induced forest dieback, increased management attention to adaptation options for enhancing forest resistance and resilience to projected climate stress can be expected

  8. Fighting Forest Fires

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Firefly is an airborne system for imaging forest fires. It uses satellite-based navigation for greater positioning accuracy and offers timeliness in fire location data delivery with on board data processing and a direct aircraft-to-fire camp communications link. Developed by Jet Propulsion Laboratory and the USFS, it has an infrared line scanner to identify fire boundaries and an infrared sensor system that can penetrate smoke to image the ground. Firefly is an outgrowth of a previous collaboration that produced FLAME, an airborne fire mapping instrument. Further refinements are anticipated by NASA and the United States Forest Service (USFS).

  9. Ecophysiology of coniferous forests

    SciTech Connect

    Smith, W.K.; Hinckley, T.M.

    1995-03-01

    This book focuses on a synthetic view of the resource physiology of conifer trees with an emphasis on developing a perspective that can integrate across the biological hierarchy. This objective is in concert with more scientific goals of maintaining biological diversity and the sustainability of forest systems. The preservation of coniferous forest ecosystems is a major concern today. The following chapters discuss different aspects of conifers. They include: genetics and the physiological ecology; long-term records of growth and distribution; plant hormones and ecophysiology; and physiological processes as related to winter dormancy, insects, climate, and air pollution. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

  10. Plant traits determine forest flammability

    NASA Astrophysics Data System (ADS)

    Zylstra, Philip; Bradstock, Ross

    2016-04-01

    Carbon and nutrient cycles in forest ecosystems are influenced by their inherent flammability - a property determined by the traits of the component plant species that form the fuel and influence the micro climate of a fire. In the absence of a model capable of explaining the complexity of such a system however, flammability is frequently represented by simple metrics such as surface fuel load. The implications of modelling fire - flammability feedbacks using surface fuel load were examined and compared to a biophysical, mechanistic model (Forest Flammability Model) that incorporates the influence of structural plant traits (e.g. crown shape and spacing) and leaf traits (e.g. thickness, dimensions and moisture). Fuels burn with values of combustibility modelled from leaf traits, transferring convective heat along vectors defined by flame angle and with plume temperatures that decrease with distance from the flame. Flames are re-calculated in one-second time-steps, with new leaves within the plant, neighbouring plants or higher strata ignited when the modelled time to ignition is reached, and other leaves extinguishing when their modelled flame duration is exceeded. The relative influence of surface fuels, vegetation structure and plant leaf traits were examined by comparing flame heights modelled using three treatments that successively added these components within the FFM. Validation was performed across a diverse range of eucalypt forests burnt under widely varying conditions during a forest fire in the Brindabella Ranges west of Canberra (ACT) in 2003. Flame heights ranged from 10 cm to more than 20 m, with an average of 4 m. When modelled from surface fuels alone, flame heights were on average 1.5m smaller than observed values, and were predicted within the error range 28% of the time. The addition of plant structure produced predicted flame heights that were on average 1.5m larger than observed, but were correct 53% of the time. The over-prediction in this

  11. Amazon Forest Responses to Drought and Fire

    NASA Astrophysics Data System (ADS)

    Morton, D. C.

    2015-12-01

    Deforestation and agricultural land uses provide a consistent source of ignitions along the Amazon frontier during the dry season. The risk of understory fires in Amazon forests is amplified by drought conditions, when fires at the forest edge may spread for weeks before rains begin. Fire activity also impacts the regional response of intact forests to drought through diffuse light effects and nutrient redistribution, highlighting the complexity of feedbacks in this coupled human and natural system. This talk will focus on recent advances in our understanding of fire-climate feedbacks in the Amazon, building on research themes initiated under NASA's Large-scale Biosphere-Atmosphere Experiment in Amazonia (LBA). NASA's LBA program began in the wake of the 1997-1998 El Niño, a strong event that exposed the vulnerability of Amazon forests to drought and fire under current climate and projections of climate change. With forecasts of another strong El Niño event in 2015-2016, this talk will provide a multi-scale synthesis of Amazon forest responses to drought and fire based on field measurements, airborne lidar data, and satellite observations of fires, rainfall, and terrestrial water storage. These studies offer new insights into the mechanisms governing fire season severity in the southern Amazon and regional variability in carbon losses from understory fires. The contributions from remote sensing to our understanding of drought and fire in Amazon forests reflect the legacy of NASA's LBA program and the sustained commitment to interdisciplinary research across the Amazon region.

  12. Evapotranspiration—Flooding Feedback in Forested Wetlands

    NASA Astrophysics Data System (ADS)

    Allen, S. T.; Keim, R.

    2015-12-01

    Evapotranspiration (ET) is a principle efflux from flooded swamps. However, for many reasons (e.g., difficulties in measuring across small gradients), controls over ET in wetlands, and swamps particularly, remain unclear. We investigate how the interaction of vegetation and hydrology controls ET and energy partitioning in flooded forests in three different hydrologic landscapes of the southeastern USA: mesohaline coastal shrub forest, floodplain hardwood forest, and backswamp baldcypress-tupelo forest. Energy components were measured by eddy covariance, sapflow, Bowen ratio energy balance, and evaporation pan to partition canopy transpiration, understory transpiration, and evaporation from floodwaters. Together, we found the energy balances of forested wetlands often differed from that of terrestrial systems, because of the potentially substantial role of evaporation from the free water surface, and flood / salinity stress inhibiting transpiration. Highest ET rates were observed in the coastal shrub forest in flooded conditions, when saline water levels dropped below the root zone (on hummocks) with concurrent lateral advection of dry air. The other two sites behaved similar to terrestrial systems, with increasing transpiration during periosd of greater water availability, although with radiation transmitted to the understory mostly partitioned to latent heat which partially compensated for the variability in canopy transpiration. Identifying these differential controls over ET is critical to understanding long-term trajectory of these systems. Many wetlands of the southeastern US have been impounded and disconnected, necessitating some degree of balance between ET and precipitation for sustainability. The positive feedbacks between ET and water levels in the coastal system suggest lower ecosystem resilience than the other two systems that showed negative feedbacks between ET and water levels.

  13. Emergence time in forest bats: the influence of canopy closure

    NASA Astrophysics Data System (ADS)

    Russo, Danilo; Cistrone, Luca; Jones, Gareth

    2007-01-01

    The role of the forest canopy in protecting bats roosting in forest from predators is poorly known. We analysed the effect of canopy closure on emergence time in Barbastella barbastellus in a mountainous area of central Italy. We used radio-tracking to locate roosts and filmed evening emergence. Comparisons were made between roosts in open areas and those in dense forest. Median emergence time and illuminance were correlated. Moreover, from pregnancy to late lactation bats emerged progressively earlier, probably because of the exceptionally high wing loading affecting pregnant bats and the high energy demand of lactation. A significant influence of canopy closure on median emergence time was revealed after adjusting for the effects of light and reproductive state. Bats in open habitat emerged later than those roosting beneath closed canopy. In cluttered habitats, predators relying on vision may find it more difficult to detect and catch bats at light levels which would offer more chances of success when attacking prey in open habitats. Bats in dense forest are less vulnerable to predators and may take advantage of an earlier emergence by prolonging foraging. Although more vulnerable, lactating females roosting at open sites may benefit from warmer roosting conditions. Roosts in dense forest may be preferred under intense predation pressure. Forest management should favour canopy heterogeneity to provide bats with a range of roosting conditions. Our work emphasises the role of a fine-grained spatial scale in the roosting ecology of forest bats.

  14. Forest Structure in Low-Diversity Tropical Forests: A Study of Hawaiian Wet and Dry Forests

    PubMed Central

    Ostertag, Rebecca; Inman-Narahari, Faith; Cordell, Susan; Giardina, Christian P.; Sack, Lawren

    2014-01-01

    The potential influence of diversity on ecosystem structure and function remains a topic of significant debate, especially for tropical forests where diversity can range widely. We used Center for Tropical Forest Science (CTFS) methodology to establish forest dynamics plots in montane wet forest and lowland dry forest on Hawai‘i Island. We compared the species diversity, tree density, basal area, biomass, and size class distributions between the two forest types. We then examined these variables across tropical forests within the CTFS network. Consistent with other island forests, the Hawai‘i forests were characterized by low species richness and very high relative dominance. The two Hawai‘i forests were floristically distinct, yet similar in species richness (15 vs. 21 species) and stem density (3078 vs. 3486/ha). While these forests were selected for their low invasive species cover relative to surrounding forests, both forests averaged 5–>50% invasive species cover; ongoing removal will be necessary to reduce or prevent competitive impacts, especially from woody species. The montane wet forest had much larger trees, resulting in eightfold higher basal area and above-ground biomass. Across the CTFS network, the Hawaiian montane wet forest was similar to other tropical forests with respect to diameter distributions, density, and aboveground biomass, while the Hawai‘i lowland dry forest was similar in density to tropical forests with much higher diversity. These findings suggest that forest structural variables can be similar across tropical forests independently of species richness. The inclusion of low-diversity Pacific Island forests in the CTFS network provides an ∼80-fold range in species richness (15–1182 species), six-fold variation in mean annual rainfall (835–5272 mm yr−1) and 1.8-fold variation in mean annual temperature (16.0–28.4°C). Thus, the Hawaiian forest plots expand the global forest plot network to enable testing of

  15. Old-growth definition for evergreen bay forests and related seral communities. Forest Service general technical report

    SciTech Connect

    McKevlin, M.R.

    1996-09-01

    This document describes old-growth conditions in an evergreen bay forest stand. Bay forests occur throughout the Atlantic and Gulf Coastal Plains. However, they are considered rare and are present across the landscape in a patchwork mosaic with other forest types in various stages of succession. Bay forests can be found associated with pocosins. Carolina bays and sandhill seeps, stream heads, and stream margins. The dominant species include loblolly-bay, sweetbay, and redbay, hence the name evergreen bay forest. However, several other swamp species associates are common, as well as many highly flammable shrub species. This forest type is subject to infrequent, high intensity, widespread disturbances such as fire. Fire is necessary to the nutrient cycling of this forest type and in conjunction with hydrology, controls succession. These stands are frequently inundated by surface water, resulting in the development of histic soils low in fertility. Alteration of the hydrology by man and catastrophic wildfire are considered to be the greatest threats to the existence of bay forests.

  16. Resistance and resilience of forest soils in the Limestone Alps

    NASA Astrophysics Data System (ADS)

    Katzensteiner, K.; Darabant, A.; Gratzer, G.

    2009-04-01

    During the last decades a dramatic increase in frequency and extent of forest disturbances, in particular of bark beetle infestations after windthrows, can be observed in Austria. In protective forests of the montane and subalpine vegetation zone, forest recovery can take several decades - a period of altered micro-climatic conditions and nutrient cycles. Soils on calcareous bedrock are considered to be particularly vulnerable under these conditions. Erosion and disintegration of ecto-organic layers of folic Histosols (Tangel) and lithic and rendzic Leptosols will lead to a loss of soil functions. In a pilot study on resilience of protective forests, soil development along chronosequences of windthrows has been surveyed in three climatically different test regions. Multivariate statistics uncover the relation between micro-topography, time since disturbance, and vegetation status on the one hand and morphological characteristics, carbon and nitrogen stocks of soils on the other hand. Factors affecting resistance and resilience of soils on calcareous bedrock are discussed.

  17. Automatic interpretation of ERTS data for forest management

    NASA Technical Reports Server (NTRS)

    Kirvida, L.; Johnson, G. R.

    1973-01-01

    Automatic stratification of forested land from ERTS-1 data provides a valuable tool for resource management. The results are useful for wood product yield estimates, recreation and wild life management, forest inventory and forest condition monitoring. Automatic procedures based on both multi-spectral and spatial features are evaluated. With five classes, training and testing on the same samples, classification accuracy of 74% was achieved using the MSS multispectral features. When adding texture computed from 8 x 8 arrays, classification accuracy of 99% was obtained.

  18. Lessons from the Rain Forest.

    ERIC Educational Resources Information Center

    Phillips, Shelley

    2002-01-01

    Presents a first-grade art project after students learned about the rain forest and heard the story, "The Great Kapok Tree: A Tale of the Amazon Rain Forest" (Lynn Cherry). Explains that the students created pictures of the rain forest. (CMK)

  19. 75 FR 11511 - Rogue River-Siskiyou National Forest; Mt. Ashland Ski Area Expansion, Jackson County, OR

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-11

    ... Forest Service Rogue River-Siskiyou National Forest; Mt. Ashland Ski Area Expansion, Jackson County, OR...-03004-PA, to conditionally authorize expansion of the Mt. Ashland Ski Area. SUMMARY: In September 2004, the Forest Service issued a Record of Decision (ROD) for the Mt. Ashland Ski Area (MASA)...

  20. Neotropical forest expansion during the last glacial period challenges refuge hypothesis.

    PubMed

    Leite, Yuri L R; Costa, Leonora P; Loss, Ana Carolina; Rocha, Rita G; Batalha-Filho, Henrique; Bastos, Alex C; Quaresma, Valéria S; Fagundes, Valéria; Paresque, Roberta; Passamani, Marcelo; Pardini, Renata

    2016-01-26

    The forest refuge hypothesis (FRH) has long been a paradigm for explaining the extreme biological diversity of tropical forests. According to this hypothesis, forest retraction and fragmentation during glacial periods would have promoted reproductive isolation and consequently speciation in forest patches (ecological refuges) surrounded by open habitats. The recent use of paleoclimatic models of species and habitat distributions revitalized the FRH, not by considering refuges as the main drivers of allopatric speciation, but instead by suggesting that high contemporary diversity is associated with historically stable forest areas. However, the role of the emerged continental shelf on the Atlantic Forest biodiversity hotspot of eastern South America during glacial periods has been ignored in the literature. Here, we combined results of species distribution models with coalescent simulations based on DNA sequences to explore the congruence between scenarios of forest dynamics through time and the genetic structure of mammal species cooccurring in the central region of the Atlantic Forest. Contrary to the FRH predictions, we found more fragmentation of suitable habitats during the last interglacial (LIG) and the present than in the last glacial maximum (LGM), probably due to topography. We also detected expansion of suitable climatic conditions onto the emerged continental shelf during the LGM, which would have allowed forests and forest-adapted species to expand. The interplay of sea level and land distribution must have been crucial in the biogeographic history of the Atlantic Forest, and forest refuges played only a minor role, if any, in this biodiversity hotspot during glacial periods.

  1. Neotropical forest expansion during the last glacial period challenges refuge hypothesis

    PubMed Central

    Costa, Leonora P.; Loss, Ana Carolina; Rocha, Rita G.; Batalha-Filho, Henrique; Bastos, Alex C.; Quaresma, Valéria S.; Fagundes, Valéria; Paresque, Roberta; Passamani, Marcelo; Pardini, Renata

    2016-01-01

    The forest refuge hypothesis (FRH) has long been a paradigm for explaining the extreme biological diversity of tropical forests. According to this hypothesis, forest retraction and fragmentation during glacial periods would have promoted reproductive isolation and consequently speciation in forest patches (ecological refuges) surrounded by open habitats. The recent use of paleoclimatic models of species and habitat distributions revitalized the FRH, not by considering refuges as the main drivers of allopatric speciation, but instead by suggesting that high contemporary diversity is associated with historically stable forest areas. However, the role of the emerged continental shelf on the Atlantic Forest biodiversity hotspot of eastern South America during glacial periods has been ignored in the literature. Here, we combined results of species distribution models with coalescent simulations based on DNA sequences to explore the congruence between scenarios of forest dynamics through time and the genetic structure of mammal species cooccurring in the central region of the Atlantic Forest. Contrary to the FRH predictions, we found more fragmentation of suitable habitats during the last interglacial (LIG) and the present than in the last glacial maximum (LGM), probably due to topography. We also detected expansion of suitable climatic conditions onto the emerged continental shelf during the LGM, which would have allowed forests and forest-adapted species to expand. The interplay of sea level and land distribution must have been crucial in the biogeographic history of the Atlantic Forest, and forest refuges played only a minor role, if any, in this biodiversity hotspot during glacial periods. PMID:26755597

  2. Neotropical forest expansion during the last glacial period challenges refuge hypothesis.

    PubMed

    Leite, Yuri L R; Costa, Leonora P; Loss, Ana Carolina; Rocha, Rita G; Batalha-Filho, Henrique; Bastos, Alex C; Quaresma, Valéria S; Fagundes, Valéria; Paresque, Roberta; Passamani, Marcelo; Pardini, Renata

    2016-01-26

    The forest refuge hypothesis (FRH) has long been a paradigm for explaining the extreme biological diversity of tropical forests. According to this hypothesis, forest retraction and fragmentation during glacial periods would have promoted reproductive isolation and consequently speciation in forest patches (ecological refuges) surrounded by open habitats. The recent use of paleoclimatic models of species and habitat distributions revitalized the FRH, not by considering refuges as the main drivers of allopatric speciation, but instead by suggesting that high contemporary diversity is associated with historically stable forest areas. However, the role of the emerged continental shelf on the Atlantic Forest biodiversity hotspot of eastern South America during glacial periods has been ignored in the literature. Here, we combined results of species distribution models with coalescent simulations based on DNA sequences to explore the congruence between scenarios of forest dynamics through time and the genetic structure of mammal species cooccurring in the central region of the Atlantic Forest. Contrary to the FRH predictions, we found more fragmentation of suitable habitats during the last interglacial (LIG) and the present than in the last glacial maximum (LGM), probably due to topography. We also detected expansion of suitable climatic conditions onto the emerged continental shelf during the LGM, which would have allowed forests and forest-adapted species to expand. The interplay of sea level and land distribution must have been crucial in the biogeographic history of the Atlantic Forest, and forest refuges played only a minor role, if any, in this biodiversity hotspot during glacial periods. PMID:26755597

  3. Reclamation of coppice forests in order to increase the potential of woody biomass in Serbia

    NASA Astrophysics Data System (ADS)

    Bjelanovic, I.; Krstic, M.

    2012-04-01

    Biomass makes 63% of the total renewable energy potential of Serbia. Here, the biomass from forests together with wood processing industry waste represent the second most important renewable source for energy production. The Action Plan for Biomass of Serbia (2010) shows that the technically exploitable biomass in the Republic of Serbia amounts annually 2.7 Mtoe. Here, the woody biomass (fuelwood, forest residue, wood processing industry residue, wood from trees outside the forest) accounts for 1.0 Mtoe while the rest originates from agricultural sources. According to the national forest inventory (2008), forest cover in Serbia accounts for 29% of the country area, having standing volume of 362.5 mil. m3 and annual increment of 9.1 mil. m3. More than half is state-owned and the rest 47% is in the private ownership. Coppice forests dominate in the forest stock (65%). According to Glavonjić (2010), northeastern and southwestern Serbia are the regions with greatest spatial forest distribution. The general forest condition is characterised by insufficient production volume, unsatisfactory stock density and forest cover, high percentage of degraded forests, unfavorable age structure, unfavorable health condition and weeded areas. Herewith, the basic measures for the improvement of forest fund (Forestry Development Strategy for Serbia, 2006) represent conversion of coppice forests, increase of forest cover and productivity of forest ecosystems by the ecologically, economically and socially acceptable methods. The actions include reclamation of degraded forests, re- and afforestation activities on abandoned agricultural, degraded and other treeless lands. The average standing volume of high forests is 254 m3·ha-1 with an annual increment of 5.5 m3·ha-1. On the contrary, coppice forests dispose 124 m3·ha-1 of standing volume, having an annual increment of 3.1 m3·ha-1. Here, estimated losses from coppice forests amount up to 3.5 mil. m3 wood annually. These data

  4. Forest Nursery Handbook.

    ERIC Educational Resources Information Center

    Katoch, C. D.

    This book is designed for forest nursery planning and management by all levels of forestry professionals and non-professionals in India and abroad, and focuses on the preparation of high quality, healthy seedlings necessary for successful afforestation programs. The book is divided into five parts that discuss: (1) details of nursery preparations…

  5. The Forest Community.

    ERIC Educational Resources Information Center

    NatureScope, 1986

    1986-01-01

    Provides: (1) background information on plant and animal relationships in forest communities; (2) four activities dealing with these relationships; and (3) five ready-to-copy pages for students. Activities include objective(s), recommended age level(s), subject area(s), list of materials needed, and procedures. (JN)

  6. Agriculture, forest, and range

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The findings and recommendations of the panel for developing a satellite remote-sensing global information system in the next decade are reported. User requirements were identified in five categories: (1) cultivated crops, (2) land resources, (3)water resources, (4)forest management, and (5) range management. The benefits from the applications of satellite data are discussed.

  7. Rain Forests: Tropical Treasures.

    ERIC Educational Resources Information Center

    Braus, Judy, Ed.

    1989-01-01

    Ranger Rick's NatureScope is a creative education series dedicated to inspiring in children an understanding and appreciation of the natural world while developing the skills they will need to make responsible decisions about the environment. The topic of this issue is "Rain Forests: Tropical Treasures." Contents are organized into the following…

  8. Forest Resource Information System

    NASA Technical Reports Server (NTRS)

    Mrocznyski, R. P.

    1983-01-01

    Twenty-three processing functions aid in utilizing LANDSAT data for forest resource management. Designed to work primarily with digital data obtained from measurements recorded by multispectral remote sensors mounted on aerospace platforms. communication between processing functions, simplicity of control, and commonality of data files in LARSFRIS enhance usefulness of system as tool for research and development of remote sensing systems.

  9. Forest Resources: An Overview

    ERIC Educational Resources Information Center

    Bethel, J. S.; Schreuder, G. F.

    1976-01-01

    Concern for long-term availability of nonrenewable resources has fostered proposals for substitution with renewable resources. Forest products could become the basis for materials substitution and production. Further feasibility studies are needed to determine the technical, economic, energy, and environmental aspects of substitution. (MR)

  10. Forest Environment Learning Experiences.

    ERIC Educational Resources Information Center

    Szuhy, Donna L. T.; Shepard, Clint L.

    Environmental education, as a teaching methodology, is appropriate for all subject areas and environments. Two teaching approaches are presented with the 13 activities in this booklet serving as examples of their application to the forest environment and different disciplines. The first approach is based upon the understanding that learners retain…

  11. Forests of Stone.

    ERIC Educational Resources Information Center

    Davidow, Beth

    1992-01-01

    Presents a geological tour of Arizona's Petrified Forest National Park, cited as containing the greatest record of life in the Triassic Period. Discusses ancient ecosystems, fossil records, geologic formations, petroglyphs, the Anasazi settlements, Painted Desert, and other park features. Includes an illustration of the fossilization process,…

  12. Minnesota's Forest Trees. Revised.

    ERIC Educational Resources Information Center

    Miles, William R.; Fuller, Bruce L.

    This bulletin describes 46 of the more common trees found in Minnesota's forests and windbreaks. The bulletin contains two tree keys, a summer key and a winter key, to help the reader identify these trees. Besides the two keys, the bulletin includes an introduction, instructions for key use, illustrations of leaf characteristics and twig…

  13. An Artful Forest

    ERIC Educational Resources Information Center

    Possick, Jennifer

    2007-01-01

    In this article, the authors' kindergarteners and a fellow first-grade class turned their hallway into a forest! Not just any mural, this culmination of a month-long project was based on observing, questioning, taking field trips, conducting library research (including the internet) and asking experts. The students developed skills in forming…

  14. Rain Forest Murals

    ERIC Educational Resources Information Center

    Kleiner, Cheryl

    2010-01-01

    The rain forest murals in the author's school began as a request from her principal to have students decorate the cafeteria with their own paintings. She decided to brainstorm ideas with her eighth-grade students. Taking into consideration the architectural space and the environmental concerns they wanted to convey, students chose the rain forest…

  15. Taiga forest stands and SAR: Monitoring for subarctic global change

    SciTech Connect

    Way, J.; Kwok, R.; Viereck, L.; Slaughter, C.; Dobson, C.

    1992-03-01

    In preparation for the first European Earth Remote Sensing (ERS-1) mission, a series of multitemporal, multifrequency, multipolarization aircraft synthetic aperture radar (SAR) data sets were acquired over the Bonanza Creek Experimental Forest near Fairbanks, Alaska in March 1988. Significant change in radar backscatter was observed over the two-week experimental period due to changing environmental conditions. These preliminary results are presented to illustrate the opportunity afforded by the ERS-1 SAR to monitor temporal change in forest ecosystems.

  16. Potential change in forest types and stand heights in central Siberia in a warming climate

    NASA Astrophysics Data System (ADS)

    Tchebakova, N. M.; Parfenova, E. I.; Korets, M. A.; Conard, S. G.

    2016-03-01

    Previous regional studies in Siberia have demonstrated climate warming and associated changes in distribution of vegetation and forest types, starting at the end of the 20th century. In this study we used two regional bioclimatic envelope models to simulate potential changes in forest types distribution and developed new regression models to simulate changes in stand height in tablelands and southern mountains of central Siberia under warming 21st century climate. Stand height models were based on forest inventory data (2850 plots). The forest type and stand height maps were superimposed to identify how heights would change in different forest types in future climates. Climate projections from the general circulation model Hadley HadCM3 for emission scenarios B1 and A2 for 2080s were paired with the regional bioclimatic models. Under the harsh A2 scenario, simulated changes included: a 80%-90% decrease in forest-tundra and tundra, a 30% decrease in forest area, a ˜400% increase in forest-steppe, and a 2200% increase in steppe, forest-steppe and steppe would cover 55% of central Siberia. Under sufficiently moist conditions, the southern and middle taiga were simulated to benefit from 21st century climate warming. Habitats suitable for highly-productive forests (≥30-40 m stand height) were simulated to increase at the expense of less productive forests (10-20 m). In response to the more extreme A2 climate the area of these highly-productive forests would increase 10%-25%. Stand height increases of 10 m were simulated over 35%-50% of the current forest area in central Siberia. In the extremely warm A2 climate scenario, the tall trees (25-30 m) would occur over 8%-12% of area in all forest types except forest-tundra by the end of the century. In forest-steppe, trees of 30-40 m may cover some 15% of the area under sufficient moisture.

  17. Riparian forest buffers mitigate the effects of deforestation on fish assemblages in tropical headwater streams.

    PubMed

    Lorion, Christopher M; Kennedy, Brian P

    2009-03-01

    Riparian forest buffers may play a critical role in moderating the impacts of deforestation on tropical stream ecosystems, but very few studies have examined the ecological effects of riparian buffers in the tropics. To test the hypothesis that riparian forest buffers can reduce the impacts of deforestation on tropical stream biota, we sampled fish assemblages in lowland headwater streams in southeastern Costa Rica representing three different treatments: (1) forested reference stream reaches, (2) stream reaches adjacent to pasture with a riparian forest buffer averaging at least 15 m in width on each bank, and (3) stream reaches adjacent to pasture without a riparian forest buffer. Land cover upstream from the study reaches was dominated by forest at all of the sites, allowing us to isolate the reach-scale effects of the three study treatments. Fish density was significantly higher in pasture reaches than in forest and forest buffer reaches, mostly due to an increase in herbivore-detritivores, but fish biomass did not differ among reach types. Fish species richness was also higher in pasture reaches than in forested reference reaches, while forest buffer reaches were intermediate. Overall, the taxonomic and trophic structure of fish assemblages in forest and forest buffer reaches was very similar, while assemblages in pasture reaches were quite distinct. These patterns were persistent across three sampling periods during our 15-month study. Differences in stream ecosystem conditions between pasture reaches and forested sites, including higher stream temperatures, reduced fruit and seed inputs, and a trend toward increased periphyton abundance, appeared to favor fish species normally found in larger streams and facilitate a native invasion process. Forest buffer reaches, in contrast, had stream temperatures and allochthonous inputs more similar to forested streams. Our results illustrate the importance of riparian areas to stream ecosystem integrity in the tropics

  18. 36 CFR 13.604 - Wildlife distance conditions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Wildlife distance conditions. 13.604 Section 13.604 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE... § 13.604 Wildlife distance conditions. (a) Approaching a bear or any large mammal within 50 yards...

  19. 36 CFR 13.604 - Wildlife distance conditions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Wildlife distance conditions. 13.604 Section 13.604 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE... § 13.604 Wildlife distance conditions. (a) Approaching a bear or any large mammal within 50 yards...

  20. 36 CFR 13.1206 - Wildlife distance conditions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Wildlife distance conditions. 13.1206 Section 13.1206 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE... Provisions § 13.1206 Wildlife distance conditions. (a) Approaching a bear or any large mammal within 50...

  1. 36 CFR 13.1206 - Wildlife distance conditions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Wildlife distance conditions. 13.1206 Section 13.1206 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE... Provisions § 13.1206 Wildlife distance conditions. (a) Approaching a bear or any large mammal within 50...

  2. 36 CFR 13.604 - Wildlife distance conditions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Wildlife distance conditions. 13.604 Section 13.604 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE... § 13.604 Wildlife distance conditions. (a) Approaching a bear or any large mammal within 50 yards...

  3. 36 CFR 13.604 - Wildlife distance conditions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Wildlife distance conditions. 13.604 Section 13.604 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE... § 13.604 Wildlife distance conditions. (a) Approaching a bear or any large mammal within 50 yards...

  4. 36 CFR 13.1206 - Wildlife distance conditions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Wildlife distance conditions. 13.1206 Section 13.1206 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE... Provisions § 13.1206 Wildlife distance conditions. (a) Approaching a bear or any large mammal within 50...

  5. 36 CFR 13.604 - Wildlife distance conditions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Wildlife distance conditions. 13.604 Section 13.604 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE... § 13.604 Wildlife distance conditions. (a) Approaching a bear or any large mammal within 50 yards...

  6. 36 CFR 13.1206 - Wildlife distance conditions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Wildlife distance conditions. 13.1206 Section 13.1206 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE... Provisions § 13.1206 Wildlife distance conditions. (a) Approaching a bear or any large mammal within 50...

  7. 36 CFR 13.1206 - Wildlife distance conditions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Wildlife distance conditions. 13.1206 Section 13.1206 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE... Provisions § 13.1206 Wildlife distance conditions. (a) Approaching a bear or any large mammal within 50...

  8. Variation in forest biomass change highlights regional differences in forest succession in the Pacific Northwest, USA.

    NASA Astrophysics Data System (ADS)

    Bell, D. M.; Gray, A. N.

    2014-12-01

    Forest successional theory describes the changes in forest biomass and community composition from forest establishment to climax communities, but the drivers of succession are still widely debated. For example, successional models have related biomass and community change to stand age, species rarity within the community, small-scale disturbance, or the ability of species to survive under low resource conditions. The degree to which these drivers might vary regionally limits our ability to model and predict ecosystem change. Our objective was to assess whether forest successional theory explains observed changes in species biomass and community composition across forests of the U. S. Pacific Northwest. Using remeasurements of 9,700 Current Vegetation Survey (CVS) National Forest inventory plots primarily in Oregon and Washington, we quantified the effects of forest stand age, community composition, disturbance, and moisture (i.e., topography and climate) on changes in species-specific proportional live biomass (ΔB) and species dominance (ΔD). We focused on differences in forest successional patterns in two vegetation zones: the Tsuga heterophylla (TSHE) zone, found at low elevations on the wet, west side of the Cascade Mountains; and the Abies concolor (ABCO) zone, found at mid-elevations on the dry, east side of the Cascade Mountains. Preliminary results indicate that the regional differences in tree species biomass change and dominance appear to be related to responses to climate and disturbance. Strong positive effects of cover change on ΔB were observed in the drier ABCO zone, but not the wetter TSHE zone. ΔB and ΔD were more often sensitive to precipitation and topographic position in the ABCO zone. In both regions, we found that ΔB was strongly negatively related to species biomass and stand age while ΔD was strongly negatively related to relative density, highlighting the importance of both age and community in shaping succession. Given that the

  9. Integrating LIDAR and forest inventories to fill the trees outside forests data gap.

    PubMed

    Johnson, Kristofer D; Birdsey, Richard; Cole, Jason; Swatantran, Anu; O'Neil-Dunne, Jarlath; Dubayah, Ralph; Lister, Andrew

    2015-10-01

    Forest inventories are commonly used to estimate total tree biomass of forest land even though they are not traditionally designed to measure biomass of trees outside forests (TOF). The consequence may be an inaccurate representation of all of the aboveground biomass, which propagates error to the outputs of spatial and process models that rely on the inventory data. An ideal approach to fill this data gap would be to integrate TOF measurements within a traditional forest inventory for a parsimonious estimate of total tree biomass. In this study, Light Detection and Ranging (LIDAR) data were used to predict biomass of TOF in all "nonforest" Forest Inventory and Analysis (FIA) plots in the state of Maryland. To validate the LIDAR-based biomass predictions, a field crew was sent to measure TOF on nonforest plots in three Maryland counties, revealing close agreement at both the plot and county scales between the two estimates. Total tree biomass in Maryland increased by 25.5 Tg, or 15.6%, when biomass of TOF were included. In two counties (Carroll and Howard), there was a 47% increase. In contrast, counties located further away from the interstate highway corridor showed only a modest increase in biomass when TOF were added because nonforest conditions were less common in those areas. The advantage of this approach for estimating biomass of TOF is that it is compatible with, and explicitly separates TOF biomass from, forest biomass already measured by FIA crews. By predicting biomass of TOF at actual FIA plots, this approach is directly compatible with traditionally reported FIA forest biomass, providing a framework for other states to follow, and should improve carbon reporting and modeling activities in Maryland. PMID:26364065

  10. Integrating LIDAR and forest inventories to fill the trees outside forests data gap.

    PubMed

    Johnson, Kristofer D; Birdsey, Richard; Cole, Jason; Swatantran, Anu; O'Neil-Dunne, Jarlath; Dubayah, Ralph; Lister, Andrew

    2015-10-01

    Forest inventories are commonly used to estimate total tree biomass of forest land even though they are not traditionally designed to measure biomass of trees outside forests (TOF). The consequence may be an inaccurate representation of all of the aboveground biomass, which propagates error to the outputs of spatial and process models that rely on the inventory data. An ideal approach to fill this data gap would be to integrate TOF measurements within a traditional forest inventory for a parsimonious estimate of total tree biomass. In this study, Light Detection and Ranging (LIDAR) data were used to predict biomass of TOF in all "nonforest" Forest Inventory and Analysis (FIA) plots in the state of Maryland. To validate the LIDAR-based biomass predictions, a field crew was sent to measure TOF on nonforest plots in three Maryland counties, revealing close agreement at both the plot and county scales between the two estimates. Total tree biomass in Maryland increased by 25.5 Tg, or 15.6%, when biomass of TOF were included. In two counties (Carroll and Howard), there was a 47% increase. In contrast, counties located further away from the interstate highway corridor showed only a modest increase in biomass when TOF were added because nonforest conditions were less common in those areas. The advantage of this approach for estimating biomass of TOF is that it is compatible with, and explicitly separates TOF biomass from, forest biomass already measured by FIA crews. By predicting biomass of TOF at actual FIA plots, this approach is directly compatible with traditionally reported FIA forest biomass, providing a framework for other states to follow, and should improve carbon reporting and modeling activities in Maryland.

  11. Mitigation benefits of forestation greatly varies on short spatial scale

    NASA Astrophysics Data System (ADS)

    Yakir, Dan; Rotenberg, Eyal; Rohatin, Shani; Ramati, Efrat; Asaf, David; Dicken, Uri

    2016-04-01

    Mitigation of global warming by forestation is controversial because of its linkage to increasing surface energy load and associated surface warming. Such tradeoffs between cooling associated with carbon sequestration and warming associated with radiative effects have been considered predominantly on large spatial scales, indicating benefits of forestation mainly in the tropics but not in the boreal regions. Using mobile laboratory for measuring CO2, water and energy flux in forest and non-forest ecosystem along the climatic gradient in Israel over three years, we show that the balance between cooling and warming effects of forestation can be transformed across small spatial scale. While converting shrubland to pine forest in a semi-arid site (280 mm annual precipitations) requires several decades of carbon sequestration to balance the radiative warming effects, similar land use change under moist Mediterranean conditions (780 mm annual precipitation) just ~200 km away showed reversal of this balance. Specifically, the results indicated that in the study region (semi-arid to humid Mediterranean), net absorb radiation in pine forests is always larger than in open space ecosystems, resulting in surface warming effects (the so-called albedo effect). Similarly, depression of thermal radiation emission, mainly due canopy skin surface cooling associated with the 'convector effect' in forests compared with shrubland ecosystems also appears in all sites. But both effects decrease by about 1/2 in going from the semi-arid to the humid Mediterranean sites, while enhanced productivity of forest compared to grassland increase about fourfold. The results indicate a greater potential for forestation as climate change mitigation strategy than previously assumed.

  12. The effect of forests on rockfall occurrence frequency

    NASA Astrophysics Data System (ADS)

    Moos, Christine; Dorren, Luuk; Stoffel, Markus

    2016-04-01

    Many forests in mountain regions protect people, settlements and infrastructure from rockfall and play an important role in risk prevention. Despite recent advances regarding forest-rockfall interactions, open questions still remain, namely on how the mitigating effect of forests can be quantitatively integrated into rockfall risk analyses. The quantification of the influence of forests on rockfall occurrence frequency is particularly demanding, even more so when related to elements at risk. The goal of this study is to quantify the effect of forests on the occurrence frequency based on rockfall simulations with the three-dimensional, process-based model Rockyfor3D. We define a constant rockfall release probability based on a power-law magnitude-frequency distribution, which is used to simulate rockfall events over a period of 1000 yrs on a virtually constructed slope. The simulations are conducted for different forest and non-forest scenarios under varying terrain conditions. These simulations firstly provide input data for the determination of rockfall occurrence frequencies at five different evaluation zones situated at 0, 150, 300, 450, and 500 m from the release area. Secondly, based on multivariate statistical models, we try to find out how specific forest and terrain characteristics control the rockfall occurrence frequency along a slope. The results for a 0.5 m3 block show, for example, that at a distance of 500 m from the release area, the occurrence frequency (expressed as a return period in years) changes from 30 yrs on a non-forested to more than 1000 yrs on a forested slope. The difference in the frequency increases with increasing distance from the release area and is less pronounced for larger block volumes (> ~1.2 m3). The results of the statistical analyses allow to quantify the effect of specific forest and terrain characteristics on the reduction of the occurrence frequency. For example, a forested slope length of 100 m with a dense forest (basal

  13. [Factors limiting distribution of the rare lichen species Lobaria pulmonaria (in forests of the Kologriv Forest Nature Reserve)].

    PubMed

    Ivanova, N V

    2015-01-01

    The distribution patterns and coenotic confines ofthe epiphytic lichen Lobaria pulmonaria have been studied. The factors limiting the habitat of this rare lichen species in the Kologriv Forest Nature Reserve (southern taiga subzone) have been revealed. It has been shown that L. pulmonaria is attracted to forest areas, which are less affected by humans and characterized by better light conditions than other communities. It has been found that L. pulmonaria is able to colonize trees at various ontogenetic states, beginning from virginal ones.

  14. The Significance of Forest Monitoring Programmes: the Finnish Perspective

    NASA Astrophysics Data System (ADS)

    Merila, P.; Derome, J.; Lindgren, M.

    2007-12-01

    Finland has been participating in the ICP Forests programme (the International Co-operative Programme on the Assessment and Monitoring of Air Pollution Effects on Forests) based on international agreements on the long- range transportation of air pollutants (LRTAP) and other associated monitoring programmes (e.g. Forest Focus, ICP Integrated Monitoring, ICP Vegetation) since 1985. The knowledge gained during the years has greatly increased our understanding of the overall condition of our forests and the factors affecting forest condition, the processes underlying forest ecosystem functioning, and the potential threats to our forests posed by human activities, both at home and abroad. The success of the monitoring activities in Finland is largely based on the experience gained during the early 1980's with our own national acidification project and, during the late 1980's and early 1990"s, in a number of regional monitoring projects. Finland's membership of the European Union (entry in 1996) has enabled us to further develop the infrastructure and coverage of both our extensive and intensive level networks. This broadening of our ecological understanding and development of international collaboration are now providing us with an invaluable basis for addressing the new monitoring challenges (biodiversity, climate change). The results gained in our monitoring activities clearly demonstrate the value of long-term monitoring programmes. The main results have been regularly reported both at the European (e.g. http://www.icp- forests.org/Reports.htm) and national level (e.g. http://www.metla.fi/julkaisut/workingpapers/2007/mwp045- en.htm). However, the datasets have not been intensively explored and exploited, and few of the important methodological and ecological findings have been published in peer-reviewed scientific journals. This has, understandably, not been the first priority of the international monitoring programmes. A number of the intensive forest monitoring

  15. Learning machines applied to potential forest distribution.

    PubMed

    Ordóñez, Celestino; Taboada, Javier; Bastante, Fernando; Matías, Jose María; Felicísimo, Angel Manuel

    2005-01-01

    The clearing of forests to obtain land for pasture and agriculture and the replacement of autochthonous species by other faster-growing varieties of trees for timber have both led to the loss of vast areas of forest worldwide. At present, many developed countries are attempting to reverse these effects, establishing policies for the restoration of older woodland systems. Reforestation is a complex matter, planned and carried out by experts who need objective information regarding the type of forest that can be sustained in each area. This information is obtained by drawing up feasibility models constructed using statistical methods that make use of the information provided by morphological and environmental variables (height, gradient, rainfall, etc.) that partially condition the presence or absence of a specific kind of forestation in an area. The aim of this work is to construct a set of feasibility models for woodland located in the basin of the River Liébana (NW Spain), to serve as a support tool for the experts entrusted with carrying out the reforestation project. The techniques used are multilayer perceptron neural networks and support vector machines. Their results will be compared to the results obtained by traditional techniques (such as discriminant analysis and logistic regression) by measuring the degree of fit between each model and the existing distribution of woodlands. The interpretation and problems of the feasibility models are commented on in the Discussion section. PMID:15984068

  16. When is a forest a forest? Forest concepts and definitions in the era of forest and landscape restoration.

    PubMed

    Chazdon, Robin L; Brancalion, Pedro H S; Laestadius, Lars; Bennett-Curry, Aoife; Buckingham, Kathleen; Kumar, Chetan; Moll-Rocek, Julian; Vieira, Ima Célia Guimarães; Wilson, Sarah Jane

    2016-09-01

    We present a historical overview of forest concepts and definitions, linking these changes with distinct perspectives and management objectives. Policies dealing with a broad range of forest issues are often based on definitions created for the purpose of assessing global forest stocks, which do not distinguish between natural and planted forests or reforests, and which have not proved useful in assessing national and global rates of forest regrowth and restoration. Implementing and monitoring forest and landscape restoration requires additional approaches to defining and assessing forests that reveal the qualities and trajectories of forest patches in a spatially and temporally dynamic landscape matrix. New technologies and participatory assessment of forest states and trajectories offer the potential to operationalize such definitions. Purpose-built and contextualized definitions are needed to support policies that successfully protect, sustain, and regrow forests at national and global scales. We provide a framework to illustrate how different management objectives drive the relative importance of different aspects of forest state, dynamics, and landscape context.

  17. When is a forest a forest? Forest concepts and definitions in the era of forest and landscape restoration.

    PubMed

    Chazdon, Robin L; Brancalion, Pedro H S; Laestadius, Lars; Bennett-Curry, Aoife; Buckingham, Kathleen; Kumar, Chetan; Moll-Rocek, Julian; Vieira, Ima Célia Guimarães; Wilson, Sarah Jane

    2016-09-01

    We present a historical overview of forest concepts and definitions, linking these changes with distinct perspectives and management objectives. Policies dealing with a broad range of forest issues are often based on definitions created for the purpose of assessing global forest stocks, which do not distinguish between natural and planted forests or reforests, and which have not proved useful in assessing national and global rates of forest regrowth and restoration. Implementing and monitoring forest and landscape restoration requires additional approaches to defining and assessing forests that reveal the qualities and trajectories of forest patches in a spatially and temporally dynamic landscape matrix. New technologies and participatory assessment of forest states and trajectories offer the potential to operationalize such definitions. Purpose-built and contextualized definitions are needed to support policies that successfully protect, sustain, and regrow forests at national and global scales. We provide a framework to illustrate how different management objectives drive the relative importance of different aspects of forest state, dynamics, and landscape context. PMID:26961011

  18. A global meta-analysis on the ecological drivers of forest restoration success.

    PubMed

    Crouzeilles, Renato; Curran, Michael; Ferreira, Mariana S; Lindenmayer, David B; Grelle, Carlos E V; Rey Benayas, José M

    2016-05-19

    Two billion ha have been identified globally for forest restoration. Our meta-analysis encompassing 221 study landscapes worldwide reveals forest restoration enhances biodiversity by 15-84% and vegetation structure by 36-77%, compared with degraded ecosystems. For the first time, we identify the main ecological drivers of forest restoration success (defined as a return to a reference condition, that is, old-growth forest) at both the local and landscape scale. These are as follows: the time elapsed since restoration began, disturbance type and landscape context. The time elapsed since restoration began strongly drives restoration success in secondary forests, but not in selectively logged forests (which are more ecologically similar to reference systems). Landscape restoration will be most successful when previous disturbance is less intensive and habitat is less fragmented in the landscape. Restoration does not result in full recovery of biodiversity and vegetation structure, but can complement old-growth forests if there is sufficient time for ecological succession.

  19. Thresholds in forest bird occurrence as a function of the amount of early-seral broadleaf forest at landscape scales

    USGS Publications Warehouse

    Betts, M.G.; Hagar, J.C.; Rivers, J.W.; Alexander, J.D.; McGarigal, K.; McComb, B.C.

    2010-01-01

    Recent declines in broadleaf-dominated, early-seral forest globally as a function of intensive forest management and/or fire suppression have raised concern about the viability of populations dependent on such forest types. However, quantitative information about the strength and direction of species associations with broadleaf cover at landscape scales are rare. Uncovering such habitat relationships is essential for understanding the demography of species and in developing sound conservation strategies. It is particularly important to detect points in habitat reduction where rates of population decline may accelerate or the likelihood of species occurrence drops rapidly (i.e., thresholds). Here, we use a large avian point-count data set (N = 4375) from southwestern and northwestern Oregon along with segmented logistic regression to test for thresholds in forest bird occurrence as a function of broadleaf forest and early-seral broadleaf forest at local (150-m radius) and landscape (500–2000-m radius) scales. All 12 bird species examined showed positive responses to either broadleaf forest in general, and/or early-seral broadleaf forest. However, regional variation in species response to these conditions was high. We found considerable evidence for landscape thresholds in bird species occurrence as a function of broadleaf cover; threshold models received substantially greater support than linear models for eight of 12 species. Landscape thresholds in broadleaf forest ranged broadly from 1.35% to 24.55% mean canopy cover. Early-seral broadleaf thresholds tended to be much lower (0.22–1.87%). We found a strong negative relationship between the strength of species association with early-seral broadleaf forest and 42-year bird population trends; species most associated with this forest type have declined at the greatest rates. Taken together, these results provide the first support for the hypothesis that reductions in broadleaf-dominated early-seral forest due to

  20. Extending large-scale forest inventories to assess urban forests.

    PubMed

    Corona, Piermaria; Agrimi, Mariagrazia; Baffetta, Federica; Barbati, Anna; Chiriacò, Maria Vincenza; Fattorini, Lorenzo; Pompei, Enrico; Valentini, Riccardo; Mattioli, Walter

    2012-03-01

    Urban areas are continuously expanding today, extending their influence on an increasingly large proportion of woods and trees located in or nearby urban and urbanizing areas, the so-called urban forests. Although these forests have the potential for significantly improving the quality the urban environment and the well-being of the urban population, data to quantify the extent and characteristics of urban forests are still lacking or fragmentary on a large scale. In this regard, an expansion of the domain of multipurpose forest inventories like National Forest Inventories (NFIs) towards urban forests would be required. To this end, it would be convenient to exploit the same sampling scheme applied in NFIs to assess the basic features of urban forests. This paper considers approximately unbiased estimators of abundance and coverage of urban forests, together with estimators of the corresponding variances, which can be achieved from the first phase of most large-scale forest inventories. A simulation study is carried out in order to check the performance of the considered estimators under various situations involving the spatial distribution of the urban forests over the study area. An application is worked out on the data from the Italian NFI.

  1. The role of forest floor and trees to the ecosystem scale methane budget of boreal forests

    NASA Astrophysics Data System (ADS)

    Pihlatie, Mari; Halmeenmäki, Elisa; Peltola, Olli; Haikarainen, Iikka; Heinonsalo, Jussi; Santalahti, Minna; Putkinen, Anuliina; Fritze, Hannu; Urban, Otmar; Machacova, Katerina

    2016-04-01

    Boreal forests are considered as a sink of atmospheric methane (CH4) due to the activity of CH4 oxidizing bacteria (methanotrophs) in the soil. This soil CH4 sink is especially strong for upland forest soils, whereas forests growing on organic soils may act as small sources due to the domination of CH4 production by methanogens in the anaerobic parts of the soil. The role of trees to the ecosystem-scale CH4 fluxes has until recently been neglected due to the perception that trees do not contribute to the CH4 exchange, and also due to difficulties in measuring the CH4 exchange from trees. Findings of aerobic CH4 formation in plants and emissions from tree-stems in temperate and tropical forests during the past decade demonstrate that our understanding of CH4 cycling in forest ecosystems is not complete. Especially the role of forest canopies still remain unresolved, and very little is known of CH4 fluxes from trees in boreal region. We measured the CH4 exchange of tree-stems and tree-canopies from pine (Pinus sylvestris), spruce (Picea abies) and birch (Betula pubescens, Betula pendula) trees growing in Southern Finland (SMEAR II station) on varying soil conditions, from upland mineral soils to paludified soil. We compared the CH4 fluxes from trees to forest-floor CH4 exchange, both measured by static chambers, and to CH4 fluxes measured above the forest canopy by a flux gradient technique. We link the CH4 fluxes from trees and forest floor to physiological activity of the trees, such as transpiration, sap-flow, CO2 net ecosystem exchange (NEE), soil properties such as temperature and moisture, and to the presence of CH4 producing methanogens and CH4 oxidizing methanotrophs in trees or soil. The above canopy CH4 flux measurements show that the whole forest ecosystem was a small source of CH4 over extended periods in the spring and summer 2012, 2014 and 2015. Throughout the 2013-2014 measurements, the forest floor was in total a net sink of CH4, with variation

  2. Secondary Forest Age and Tropical Forest Biomass Estimation Using TM

    NASA Technical Reports Server (NTRS)

    Nelson, R. F.; Kimes, D. S.; Salas, W. A.; Routhier, M.

    1999-01-01

    The age of secondary forests in the Amazon will become more critical with respect to the estimation of biomass and carbon budgets as tropical forest conversion continues. Multitemporal Thematic Mapper data were used to develop land cover histories for a 33,000 Square kM area near Ariquemes, Rondonia over a 7 year period from 1989-1995. The age of the secondary forest, a surrogate for the amount of biomass (or carbon) stored above-ground, was found to be unimportant in terms of biomass budget error rates in a forested TM scene which had undergone a 20% conversion to nonforest/agricultural cover types. In such a situation, the 80% of the scene still covered by primary forest accounted for over 98% of the scene biomass. The difference between secondary forest biomass estimates developed with and without age information were inconsequential relative to the estimate of biomass for the entire scene. However, in futuristic scenarios where all of the primary forest has been converted to agriculture and secondary forest (55% and 42% respectively), the ability to age secondary forest becomes critical. Depending on biomass accumulation rate assumptions, scene biomass budget errors on the order of -10% to +30% are likely if the age of the secondary forests are not taken into account. Single-date TM imagery cannot be used to accurately age secondary forests into single-year classes. A neural network utilizing TM band 2 and three TM spectral-texture measures (bands 3 and 5) predicted secondary forest age over a range of 0-7 years with an RMSE of 1.59 years and an R(Squared) (sub actual vs predicted) = 0.37. A proposal is made, based on a literature review, to use satellite imagery to identify general secondary forest age groups which, within group, exhibit relatively constant biomass accumulation rates.

  3. Fishers, farms, and forests in eastern North America.

    PubMed

    Lancaster, Pamela A; Bowman, Jeff; Pond, Bruce A

    2008-07-01

    The fisher (Martes pennanti) has recently recovered from historic extirpations across much of its geographic range. There are at least five explanations for the recovery of the fisher, including changes in the amount of habitat, the suitability of habitat, trapping pressure, societal attitudes toward predators, and climate. We evaluated a recovering fisher population in Ontario to test two conditions we viewed as necessary to support the hypothesis that fisher populations have increased due to an increase in the amount of forested land. First, we tested whether the amount of forested land has increased. Second, we tested whether contemporary fisher abundance (and therefore habitat quality) was related to the amount of forest. Topographic maps showed that the proportion of forested land in the study area had increased by 1.9% per decade since 1934 and 3.3% per decade since 1959, likely as a result of land conversion from agricultural uses. Overall the proportion of the study area that was forested increased from 29% to 40% during 1934 to 1995. Census data from the region indicated that there had been a decline in the amount of land area being farmed during the last 50 years. Recent livetrapping data showed that fisher abundance was positively related to the proportion of landscapes that were forested. Based on our results, we could not reject the hypothesis that an increase in the amount of forested land has contributed to the recovery of fisher populations.

  4. Shifts in soil testate amoeba communities associated with forest diversification.

    PubMed

    Bobrov, Anatoly A; Zaitsev, Andrei S; Wolters, Volkmar

    2015-05-01

    We studied changes of testate amoeba communities associated with the conversion of spruce monocultures into mixed beech-fir-spruce forests in the Southern Black Forest Mountains (Germany). In this region, forest conversion is characterized by a gradual development of beech undergrowth within thinned spruce tree stands leading to multiple age continuous cover forests with a diversified litter layer. Strong shifts in the abundance of testate amoeba observed in intermediate stages levelled off to monoculture conditions again after the final stage of the conversion process had been reached. The average number of species per conversion stage (i.e., local richness) did not respond strongly to forest conversion, but the total number of species (i.e., regional richness) was considerably higher in the initial stage than in the mixed forests, due to the large number of hygrophilous species inhabiting spruce monocultures. Functional diversity of the testate amoeba community, however, significantly increased during the conversion process. This shift was closely associated with improved C and N availability as well as higher niche diversity in the continuous cover stands. Lower soil acidity in these forests coincided with a higher relative abundance of eurytopic species. Our results suggest that testate amoeba communities are much more affected by physicochemical properties of the soil than directly by litter diversity.

  5. Accounting for risk in valuing forest carbon offsets

    PubMed Central

    Hurteau, Matthew D; Hungate, Bruce A; Koch, George W

    2009-01-01

    Background Forests can sequester carbon dioxide, thereby reducing atmospheric concentrations and slowing global warming. In the U.S., forest carbon stocks have increased as a result of regrowth following land abandonment and in-growth due to fire suppression, and they currently sequester approximately 10% of annual US emissions. This ecosystem service is recognized in greenhouse gas protocols and cap-and-trade mechanisms, yet forest carbon is valued equally regardless of forest type, an approach that fails to account for risk of carbon loss from disturbance. Results Here we show that incorporating wildfire risk reduces the value of forest carbon depending on the location and condition of the forest. There is a general trend of decreasing risk-scaled forest carbon value moving from the northern toward the southern continental U.S. Conclusion Because disturbance is a major ecological factor influencing long-term carbon storage and is often sensitive to human management, carbon trading mechanisms should account for the reduction in value associated with disturbance risk. PMID:19149889

  6. Using urban forest assessment tools to model bird habitat potential

    USGS Publications Warehouse

    Lerman, Susannah B.; Nislow, Keith H.; Nowak, David J.; Destefano, Stephen; King, David I.; Jones-Farrand, D. Todd

    2014-01-01

    The alteration of forest cover and the replacement of native vegetation with buildings, roads, exotic vegetation, and other urban features pose one of the greatest threats to global biodiversity. As more land becomes slated for urban development, identifying effective urban forest wildlife management tools becomes paramount to ensure the urban forest provides habitat to sustain bird and other wildlife populations. The primary goal of this study was to integrate wildlife suitability indices to an existing national urban forest assessment tool, i-Tree. We quantified available habitat characteristics of urban forests for ten northeastern U.S. cities, and summarized bird habitat relationships from the literature in terms of variables that were represented in the i-Tree datasets. With these data, we generated habitat suitability equations for nine bird species representing a range of life history traits and conservation status that predicts the habitat suitability based on i-Tree data. We applied these equations to the urban forest datasets to calculate the overall habitat suitability for each city and the habitat suitability for different types of land-use (e.g., residential, commercial, parkland) for each bird species. The proposed habitat models will help guide wildlife managers, urban planners, and landscape designers who require specific information such as desirable habitat conditions within an urban management project to help improve the suitability of urban forests for birds.

  7. CO2 fluxes near a forest edge: a numerical study.

    PubMed

    Sogachev, Andrey; Leclerc, Monique Y; Zhang, Gengsheng; Rannik, Ullar; Vesala, Timo

    2008-09-01

    In contrast with recent advances on the dynamics of the flow at a forest edge, few studies have considered its role on scalar transport and, in particular, on CO2 transfer. The present study addresses the influence of the abrupt roughness change on forest atmosphere CO2 exchange and contrasts the concentration and flux fields against those of a uniform forested surface. We use an atmospheric boundary layer two-equation closure model that accounts for the flow dynamics and vertical divergence of CO2 sources/sinks within a plant canopy. This paper characterizes the spatial variation of CO2 fluxes as a function of both sources/sinks distribution and the vertical structure of the canopy. Results suggest that the ground source plays a major role in the formation of wave-like vertical CO2 flux behavior downwind of a forest edge, despite the fact that the contribution of foliage sources/sinks changes monotonously. Such a variation is caused by scalar advection in the trunk space and reveals itself as a decrease or increase in vertical fluxes over the forest relative to carbon dioxide exchange of the underlying forest. The effect was more pronounced in model forests where the leaf area is concentrated in the upper part of the canopy. These results can be useful both for interpretation of existing measurements of net ecosystem exchange of CO2 (NEE) from flux towers in limited fetch conditions and in planning future CO2 transport experiments.

  8. CO2 fluxes near a forest edge: a numerical study.

    PubMed

    Sogachev, Andrey; Leclerc, Monique Y; Zhang, Gengsheng; Rannik, Ullar; Vesala, Timo

    2008-09-01

    In contrast with recent advances on the dynamics of the flow at a forest edge, few studies have considered its role on scalar transport and, in particular, on CO2 transfer. The present study addresses the influence of the abrupt roughness change on forest atmosphere CO2 exchange and contrasts the concentration and flux fields against those of a uniform forested surface. We use an atmospheric boundary layer two-equation closure model that accounts for the flow dynamics and vertical divergence of CO2 sources/sinks within a plant canopy. This paper characterizes the spatial variation of CO2 fluxes as a function of both sources/sinks distribution and the vertical structure of the canopy. Results suggest that the ground source plays a major role in the formation of wave-like vertical CO2 flux behavior downwind of a forest edge, despite the fact that the contribution of foliage sources/sinks changes monotonously. Such a variation is caused by scalar advection in the trunk space and reveals itself as a decrease or increase in vertical fluxes over the forest relative to carbon dioxide exchange of the underlying forest. The effect was more pronounced in model forests where the leaf area is concentrated in the upper part of the canopy. These results can be useful both for interpretation of existing measurements of net ecosystem exchange of CO2 (NEE) from flux towers in limited fetch conditions and in planning future CO2 transport experiments. PMID:18767622

  9. Dynamics of carbon fluxes above a hemiboreal mixed forest

    NASA Astrophysics Data System (ADS)

    Krasnova, Alisa; Noe, Steffen M.; Niinemets, Ülo; Krasnov, Dmitrii

    2015-04-01

    Forest ecosystems are a major part of the biosphere and control land surface-atmosphere interactions. They influence atmospheric composition and climate significantly being sources and sinks of trace gases and energy. Mixed stands of both coniferous and deciduous tree species are characterized by greater seasonal variability of forest microclimate, canopy shape and density, length of growing season and plant activity and higher biota diversity and compared to pure boreal forests. These factors coupled with physical environment (atmospheric and meteorological conditions, soil properties) influence CO2 exchange between forest and the atmosphere. To explore complex interactions within ecosystem-atmosphere continuum of hemiboreal forest SMEAR Estonia station was established in Järvselja, Estonia. A 24 m height scaffolding tower located in a forest stand dominated by Norway spruce (Picea abies (L.) Karst.) with co-domination of Silver birch (Betula pendula Roth.) and Black alder (Alnus glutinosa L.) was used to study eddy-covariance fluxes of CO2. We present the results from the first continuous EC measurements over a hemiboreal mixed forest performed in 2011-2012. The focus of the study is on diurnal and annual dynamics of carbon fluxes and the influence of main environmental drivers.

  10. Climate-induced forest dieback: An escalating global phenomenon?

    USGS Publications Warehouse

    Allen, C.D.

    2009-01-01

    The impacts of growing human populations and economies are both rapidly and directly transforming forests in many areas. However, little known are the pervasive effects of the ongoing climatic changes on the condition and status of forests around the world. Global patterns are now evident with the global tree mortality that is now above its usual mortality levels as it is affected by drought and heat-related forest stress and dieback. Thus, the possibility of an increased risk of climate-induced dieback is now being considered within many of the forests and woodlands of today. A focus will be given on the climatic water stress that is driven by both drought and warm temperatures. However, studying the trends in forest mortality and predictions has its limitations with such a number of information gaps and scientific uncertainties. First is the absence of an adequate global data on forest health status, followed by the fact that only a few tree species have the researchers an adequate quantitative knowledge with regards to its physiological thresholds of individual tree mortality from chronic or acute water stress. Lastly, the adequate knowledge of the feedback and non-linear interactions between climate-induced forest stress and other climate-related disturbance processes are lacking among the current scientists.

  11. Structure and composition of altered riparian forests in an agricultural Amazonian landscape.

    PubMed

    Nagy, R Chelsea; Porder, Stephen; Neill, Christopher; Brando, Paulo; Quintino, Raimundo Mota; do Nascimento, Sebastiâo Aviz

    2015-09-01

    Deforestation and fragmentation influence the microclimate, vegetation structure, and composition of remaining patches of tropical forest. In the southern Amazon, at the frontier of cropland expansion, forests are converted and fragmented in a pattern that leaves standing riparian forests whose dimensions are mandated by the Brazilian National Forest Code. These altered riparian forests share many characteristics of well-studied upland forest fragments, but differ because they remain connected to larger areas of forest downstream, and because they may experience wetter soil conditions because reduction of forest cover in the surrounding watershed raises groundwater levels and increases stream runoff. We compared forest regeneration, structure, composition, and diversity in four areas of intact riparian forest and four areas each of narrow, medium, and wide altered riparian forests that have been surrounded by agriculture since the early 1980s. We found that seedling abundance was reduced by as much as 64% and sapling abundance was reduced by as much as 67% in altered compared to intact riparian forests. The most pronounced differences between altered and intact forest occurred near forest edges and within the narrowest sections of altered riparian forests. Woody plant species composition differed and diversity was reduced in altered forests compared to intact riparian forests. However, despite being fragmented for several decades, large woody plant biomass and carbon storage, the number of live or dead large woody plants, mortality rates, and the size distribution of woody plants did not differ significantly between altered and intact riparian forests. Thus, even in these relatively narrow forests with high edge: area ratios, we saw no evidence of the increases in mortality and declines in biomass that have been found in other tropical forest fragment studies. However, because of the changes in both species community and reduced regeneration, it is unclear how long

  12. Structure and composition of altered riparian forests in an agricultural Amazonian landscape.

    PubMed

    Nagy, R Chelsea; Porder, Stephen; Neill, Christopher; Brando, Paulo; Quintino, Raimundo Mota; do Nascimento, Sebastiâo Aviz

    2015-09-01

    Deforestation and fragmentation influence the microclimate, vegetation structure, and composition of remaining patches of tropical forest. In the southern Amazon, at the frontier of cropland expansion, forests are converted and fragmented in a pattern that leaves standing riparian forests whose dimensions are mandated by the Brazilian National Forest Code. These altered riparian forests share many characteristics of well-studied upland forest fragments, but differ because they remain connected to larger areas of forest downstream, and because they may experience wetter soil conditions because reduction of forest cover in the surrounding watershed raises groundwater levels and increases stream runoff. We compared forest regeneration, structure, composition, and diversity in four areas of intact riparian forest and four areas each of narrow, medium, and wide altered riparian forests that have been surrounded by agriculture since the early 1980s. We found that seedling abundance was reduced by as much as 64% and sapling abundance was reduced by as much as 67% in altered compared to intact riparian forests. The most pronounced differences between altered and intact forest occurred near forest edges and within the narrowest sections of altered riparian forests. Woody plant species composition differed and diversity was reduced in altered forests compared to intact riparian forests. However, despite being fragmented for several decades, large woody plant biomass and carbon storage, the number of live or dead large woody plants, mortality rates, and the size distribution of woody plants did not differ significantly between altered and intact riparian forests. Thus, even in these relatively narrow forests with high edge: area ratios, we saw no evidence of the increases in mortality and declines in biomass that have been found in other tropical forest fragment studies. However, because of the changes in both species community and reduced regeneration, it is unclear how long

  13. A forester's look at the application of image manipulation techniques to multitemporal Landsat data

    NASA Technical Reports Server (NTRS)

    Williams, D. L.; Stauffer, M. L.; Leung, K. C.

    1979-01-01

    Registered, multitemporal Landsat data of a study area in central Pennsylvania were analyzed to detect and assess changes in the forest canopy resulting from insect defoliation. Images taken July 19, 1976, and June 27, 1977, were chosen specifically to represent forest canopy conditions before and after defoliation, respectively. Several image manipulation and data transformation techniques, developed primarily for estimating agricultural and rangeland standing green biomass, were applied to these data. The applicability of each technique for estimating the severity of forest canopy defoliation was then evaluated. All techniques tested had highly correlated results. In all cases, heavy defoliation was discriminated from healthy forest. Areas of moderate defoliation were confused with healthy forest on northwest (NW) aspects, but were distinct from healthy forest conditions on southeast (SE)-facing slopes.

  14. Balancing multiple objectives using a classification-based forest management system in Changbai Mountains, China.

    PubMed

    Zhao, Fuqiang; Yang, Jian; Liu, Zhihua; Dai, Limin; He, Hong S

    2011-12-01

    Contemporary forest management often consists of multiple objectives, including restoration of human-impacted forested landscapes toward their range of natural variability (RNV) and sustainable levels of timber production. Balancing multiple management objectives is often challenging due to intrinsic conflicts between these objectives and a lack of reference conditions for evaluating the effectiveness of forest restoration efforts. We used a spatially explicit forest landscape model to assess how well a classification-based forest management (CFM) system could achieve multiple objectives in a Korean pine broadleaf mixed forest ecosystem at Changbai Mountain in Northeast China. The CFM system divided the forest landscape into three management areas (Commercial Forest, Special Ecological Welfare Forest, and General Ecological Welfare Forest), each with its own management objectives and prescriptions, but with an overall goal of increasing the ecological and economic sustainability of the entire landscape. The zoning approach adopted in the Chinese CFM system is very similar to the TRIAD approach that is being advocated for managing public forests in Canada. In this study, a natural disturbance scenario and seven harvest scenarios (one identical to the current harvest regime and six alternative scenarios) were simulated to examine how tree species composition, age structure, and timber production at the landscape level can be affected by different strategies under the CFM system. The results indicated that the current forest management regime would not only fail to reach the designated timber production level but also move the forest landscape far away from its RNV. In order to return the currently altered forest landscape to approach its RNV while providing a stable level of timber production over time, harvest intensities should be reduced to a level that is equivalent to the amount of timber removals that would occur under the natural disturbances; and the

  15. Balancing Multiple Objectives Using a Classification-Based Forest Management System in Changbai Mountains, China

    NASA Astrophysics Data System (ADS)

    Zhao, Fuqiang; Yang, Jian; Liu, Zhihua; Dai, Limin; He, Hong S.

    2011-12-01

    Contemporary forest management often consists of multiple objectives, including restoration of human-impacted forested landscapes toward their range of natural variability (RNV) and sustainable levels of timber production. Balancing multiple management objectives is often challenging due to intrinsic conflicts between these objectives and a lack of reference conditions for evaluating the effectiveness of forest restoration efforts. We used a spatially explicit forest landscape model to assess how well a classification-based forest management (CFM) system could achieve multiple objectives in a Korean pine broadleaf mixed forest ecosystem at Changbai Mountain in Northeast China. The CFM system divided the forest landscape into three management areas (Commercial Forest, Special Ecological Welfare Forest, and General Ecological Welfare Forest), each with its own management objectives and prescriptions, but with an overall goal of increasing the ecological and economic sustainability of the entire landscape. The zoning approach adopted in the Chinese CFM system is very similar to the TRIAD approach that is bei