WorldWideScience

Sample records for forest ii effects

  1. Monitoring the effects of air-quality on forests: An overview of the Sierra Ancha Experimental Forest ICP-Level II Site

    Science.gov (United States)

    Peter E. Koestner; Karen A. Koestner; Daniel G. Neary

    2012-01-01

    The Sierra Ancha International Cooperative Program on Assessment and Monitoring of Air Pollution Effects on Forests study site or (SAEF-ICP II) is part of an international network of cooperative forest monitoring sites spread throughout Europe and the United States. The United Nations Economic Commission for Europe established the ICP II network in 1985 to monitor long...

  2. Chemistry in forest biorefineries II - BIORAFF II

    Energy Technology Data Exchange (ETDEWEB)

    Hupa, M. (Aabo Akademi, Turku (Finland). Process Chemistry Centre), Email: mhupa@abo.fi; Auer, M. (Aabo Akademi, Turku (Finland). Process Chemistry Centre), Email: mauer@abo.fi

    2010-10-15

    The biorefinery concept may be compared to an oil refinery and petrochemical plant, where fuels and numerous intermediates are produced for further processing into high-value and speciality materials. In biorefineries, the raw material instead of mineral oil is biobased material. Biorefinery development at the US and European level mostly covers the use of annual crops and other bio-based materials. However, in this project focus is on non-food materials primarily in industrial pulp and paper processes and this project is limited to forest-based biorefineries. The aim of the project is also to preserve the molecular structures created by the nature as much as possible, to explore new separation and purification methods and look at new applications in the areas such as: functional food, nutritional additives, functional additives in paper making, antioxidants, new biobased materials and biobased energy. As the area, in spite of efforts to limit it, is very large, we have selected to focus on a limited number of concretised projects, which to our knowledge are complementary with other efforts for promoting biorefinery concepts. As highlights about promising results are studies on extraction of wood and derivatisations of hemicelluloses. The goals here are twofold; we are looking for the additional functionalities for hemicelluloses and searching for new applications. Hemicelluloses in many applications would benefit from the modification of the structure, especially to improve compatibility and solubility in some applications. Research on metals in trees and fuels, release of elements in combustion, pyrolysis and sorption studies have produced new knowledge. (orig.)

  3. Chemistry in forest biorefineries II - BIORAFF II

    Energy Technology Data Exchange (ETDEWEB)

    Hupa, M.; Auer, M. (Aabo Akademi University, Turku (Finland), Process Chemistry Centre), e-mail: mhupa@abo.fi, e-mail: mauer@abo.fi

    2011-11-15

    The biorefinery concept may be compared to an oil refinery and petrochemical plant, where fuels and numerous intermediates are produced for further processing into high-value and speciality materials. In biorefineries, the raw material instead of mineral oil is bio-based material. Biorefinery development at the US and European level mostly covers the use of annual crops and other bio-based materials. However, in this project focus is on non-food materials primarily in industrial pulp and paper processes and this project is limited to forest-based biorefineries. The aim of the project is also to preserve the molecular structures created by the nature as much as possible, to explore new separation and purification methods and look at new applications in the areas such as: functional food, nutritional additives, functional additives in paper making, antioxidants, new biobased materials and biobased energy. As the area, in spite of efforts to limit it, is very large, we have selected to focus on a limited number of concretised projects, which to our knowledge are complementary with other efforts for promoting biorefinery concepts. As highlights about promising results are studies on extraction of wood and derivatisations of hemicelluloses. The goals here are twofold; we are looking for the additional functionalities for hemicelluloses and search of new applications. Hemicelluloses in many applications would benefit from the modification of the structure, especially to improve compatibility and solubility in some applications. Research on metals in trees and fuels, release of elements in combustion, pyrolysis and sorption studies have produced new knowledge. (orig.)

  4. Simulating ungulate herbivory across forest landscapes: A browsing extension for LANDIS-II

    Science.gov (United States)

    DeJager, Nathan R.; Drohan, Patrick J.; Miranda, Brian M.; Sturtevant, Brian R.; Stout, Susan L.; Royo, Alejandro; Gustafson, Eric J.; Romanski, Mark C.

    2017-01-01

    Browsing ungulates alter forest productivity and vegetation succession through selective foraging on species that often dominate early succession. However, the long-term and large-scale effects of browsing on forest succession are not possible to project without the use of simulation models. To explore the effects of ungulates on succession in a spatially explicit manner, we developed a Browse Extension that simulates the effects of browsing ungulates on the growth and survival of plant species cohorts within the LANDIS-II spatially dynamic forest landscape simulation model framework. We demonstrate the capabilities of the new extension and explore the spatial effects of ungulates on forest composition and dynamics using two case studies. The first case study examined the long-term effects of persistently high white-tailed deer browsing rates in the northern hardwood forests of the Allegheny National Forest, USA. In the second case study, we incorporated a dynamic ungulate population model to simulate interactions between the moose population and boreal forest landscape of Isle Royale National Park, USA. In both model applications, browsing reduced total aboveground live biomass and caused shifts in forest composition. Simulations that included effects of browsing resulted in successional patterns that were more similar to those observed in the study regions compared to simulations that did not incorporate browsing effects. Further, model estimates of moose population density and available forage biomass were similar to previously published field estimates at Isle Royale and in other moose-boreal forest systems. Our simulations suggest that neglecting effects of browsing when modeling forest succession in ecosystems known to be influenced by ungulates may result in flawed predictions of aboveground biomass and tree species composition.

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

    African Journals Online (AJOL)

    Until 1983, uncontrolled wildfires were relatively uncommon especially in the forest zones of Ghana. However, the period following the 1980s has seen a significant rise in wildfires, with devastating effects on forest resources and sustainable agricultural livelihoods. Thus, the rise in wildfire incidence in Ghana since 1983 ...

  6. Nitrogen turnover and effects in forests

    International Nuclear Information System (INIS)

    Erisman, J.W.; De Vries, W.

    1999-10-01

    Apart from effects on the crown condition, atmospheric deposition also affects the nutritional status of forests. This refers specifically to the impact of N deposition that has gained in importance since the last decades due to steady decline in S emissions over that period. Preliminary data of bulk deposition and throughfall at some 60 Intensive Monitoring (level II) plots suggest that the average input of N and S is about equal. At low N deposition, an increase may be beneficial for forest growth, whereas the reverse may be true at elevated deposition. The relative contribution of the different fluxes in the nitrogen cycle is reasonably well known, with the exception of denitrification. The quantification of the input and output fluxes and the allocation of deposited nitrogen in the forest ecosystem prove to be difficult. Although knowledge on the response of forest ecosystems to N inputs has increased over the last decade, there is still a lack of information on the dynamics in critical N loads over a large range of environmental conditions. Furthermore, a European wide perspective of N saturation is still lacking. 132 refs

  7. The Missouri Ozark Forest Ecosystem Project: the effects of forest management on the forest ecosystem

    Science.gov (United States)

    Brian Brookshire; Carl Hauser

    1993-01-01

    The effects of forest management on non-timber resources are of growing concern to forest managers and the public. While many previous studies have reported effects of stand-level treatments (less than 15 ha) on various stand-level attributes, few studies have attempted to document the influence of forest management on the biotic and abiotic characteristics of entire...

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

    DEFF Research Database (Denmark)

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

    2006-01-01

    deposition (> 8-10 kg ha(-1) a(-1)). We synthesized the current understanding of factors controlling N leaching in relation to three primary causes of N cycle disruption: (i) Increased N input (air pollution, fertilization, N-2 fixing plants). In European forests, elevated N deposition explains approximately...... conifer forests receive higher N deposition and exhibit higher nitrate loss than deciduous forests; an exception is alder that shows substantial nitrate leaching through N fixation input. Fertilization with N poses limited risk to water quality, when applied to N-limited forests. (ii) Reduced plant uptake...... of the nitrate response is especially connected to the recovery of the vegetation sink. Less intensive disturbances like thinning have only minor effects on N loss. (iii) Enhanced mineralization of soil N (liming, ditching, climate change). Responses in nitrate leaching after liming may increase with N...

  9. Deforestation effects on Amazon forest resilience

    Science.gov (United States)

    Zemp, D. C.; Schleussner, C.-F.; Barbosa, H. M. J.; Rammig, A.

    2017-06-01

    Through vegetation-atmosphere feedbacks, rainfall reductions as a result of Amazon deforestation could reduce the resilience on the remaining forest to perturbations and potentially lead to large-scale Amazon forest loss. We track observation-based water fluxes from sources (evapotranspiration) to sinks (rainfall) to assess the effect of deforestation on continental rainfall. By studying 21st century deforestation scenarios, we show that deforestation can reduce dry season rainfall by up to 20% far from the deforested area, namely, over the western Amazon basin and the La Plata basin. As a consequence, forest resilience is systematically eroded in the southwestern region covering a quarter of the current Amazon forest. Our findings suggest that the climatological effects of deforestation can lead to permanent forest loss in this region. We identify hot spot regions where forest loss should be avoided to maintain the ecological integrity of the Amazon forest.

  10. [Effects of climate change on forest succession].

    Science.gov (United States)

    Wang, Jijun; Pei, Tiefan

    2004-10-01

    Forest regeneration is an important process driven by forest ecological dynamic resources. More and more concern has been given to forest succession issues since the development of forest succession theory during the early twentieth century. Scientific management of forest ecosystem entails the regulations and research models of forest succession. It is of great practical and theoretical significance to restore and reconstruct forest vegetation and to protect natural forest. Disturbances are important factors affecting regeneration structure and ecological processes. They result in temporal and spatial variations of forest ecosystem, and change the efficiencies of resources. In this paper, some concepts about forest succession and disturbances were introduced, and the difficulties of forest succession were proposed. Four classes of models were reviewed: Markov model, GAP model, process-based equilibrium terrestrial biosphere models (BIOME series models), and non-linear model. Subsequently, the effects of climate change on forest succession caused by human activity were discussed. At last, the existing problem and future research directions were proposed.

  11. Probing HeII Reionization at z>3.5 with Resolved HeII Lyman Alpha Forest Spectra

    Science.gov (United States)

    Worseck, Gabor

    2017-08-01

    The advent of GALEX and COS have revolutionized our view of HeII reionization, the final major phase transition of the intergalactic medium. COS spectra of the HeII Lyman alpha forest have confirmed with high confidence the high HeII transmission that signifies the completion of HeII reionization at z 2.7. However, the handful of z>3.5 quasars observed to date show a set of HeII transmission 'spikes' and larger regions with non-zero transmission that suggest HeII reionization was well underway by z=4. This is in striking conflict with predictions from state-of-the-art radiative transfer simulations of a HeII reionization driven by bright quasars. Explaining these measurements may require either faint quasars or more exotic sources of hard photons at z>4, with concomitant implications for HI reionization. However, many of the observed spikes are unresolved in G140L spectra and are significantly impacted by Poisson noise. Current data cannot reliably probe the ionization state of helium at z>3.5.We request 41 orbits to obtain science-grade G130M spectra of the two UV-brightest HeII-transmitting QSOs at z>3.5 to confirm and resolve their HeII transmission spikes as an unequivocal test of early HeII reionization. These spectra are complemented by recently obtained data from 8m telescopes: (1) Echelle spectra of the coeval HI Lya forest to map the underlying density field that modulates the HeII absorption, and (2) Our dedicated survey for foreground QSOs that may source the HeII transmission. Our recent HST programs revealed the only two viable targets to resolve the z>3.5 HeII Lyman alpha forest, and to conclusively solve this riddle.

  12. Effects of Deforestation and Forest Degradation on Forest Carbon Stocks in Collaborative Forests, Nepal

    Directory of Open Access Journals (Sweden)

    Ram Asheshwar MANDAL

    2012-12-01

    Full Text Available There are some key drivers that favor deforestation and forest degradation. Consequently, levels of carbon stock are affected in different parts of same forest types. But the problem lies in exploring the extent of the effects on level of carbon stocking. This paper highlights the variations in levels of carbon stocks in three different collaborative forests of same forest type i.e. tropical sal (Shorea robusta forest in Mahottari district of the central Terai in Nepal. Three collaborative forests namely Gadhanta-Bardibas Collaborative Forest (CFM, Tuteshwarnath CFM and Banke- Maraha CFM were selected for research site. Interview and workshops were organized with the key informants that include staffs, members and representatives of CFMs to collect the socio-economic data and stratified random sampling was applied to collect the bio-physical data to calculate the carbon stocks. Analysis was carried out using statistical tools. It was found five major drivers namely grazing, fire, logging, growth of invasive species and encroachment. It was found highest carbon 269.36 ton per ha in Gadhanta- Bardibash CFM. The findings showed that the levels of carbon stocks in the three studied CFMs are different depending on how the drivers of deforestation and forest degradation influence over them.

  13. Predicted effects of gypsy moth defoliation and climate change on forest carbon dynamics in the New Jersey Pine Barrens

    Science.gov (United States)

    Alec M. Kretchun; Robert M. Scheller; Melissa S. Lucash; Kenneth L. Clark; John Hom; Steve Van Tuyl; Michael L. Fine

    2014-01-01

    Disturbance regimes within temperate forests can significantly impact carbon cycling. Additionally, projected climate change in combination with multiple, interacting disturbance effects may disrupt the capacity of forests to act as carbon sinks at large spatial and temporal scales. We used a spatially explicit forest succession and disturbance model, LANDIS-II, to...

  14. The effects of forest fragmentation on forest stand attributes

    Science.gov (United States)

    Ronald E. McRoberts; Greg C. Liknes

    2002-01-01

    For two study areas in Minnesota, USA, one heavily forested and one sparsely forested, maps of predicted proportion forest area were created using Landsat Thematic Mapper imagery, forest inventory plot data, and a logistic regression model. The maps were used to estimate quantitative indices of forest fragmentation. Correlations between the values of the indices and...

  15. Occlusion effects, Part II

    DEFF Research Database (Denmark)

    Hansen, Mie Østergaard

    The present report studies the mechanism of the occlusion effect by means of literature studies, experiments and model estimates. A mathematical model of the occlusion effect is developed. The model includes the mechanical properties of the earmould and the airborne sound as well as the body...... conducted sound from own voice. These aspects are new in the sense that previous studies disregard the earmould mechanics and includes only one sound source placed in the ear canal....

  16. Late-successional forests and northern spotted owls: how effective is the Northwest Forest Plan?

    Science.gov (United States)

    Miles Hemstrom; Martin G. Raphael

    2000-01-01

    This paper describes the late-successional and old-growth forest and the northern spotted owl effectiveness monitoring plans for the Northwest Forest Plan. The effectiveness monitoring plan for late-successional and old-growth forests will track changes in forest spatial distribution, and within-stand structure and composition, and it will predict future trends.

  17. Assessing urban forest effects and values: Morgantown's Urban Forest

    Science.gov (United States)

    David J. Nowak; Robert E. III Hoehn; Daniel E. Crane; Jack C. Stevens; Jonathan Cumming; Sandhya Mohen; Anne Buckelew. Cumming

    2012-01-01

    An analysis of the community forest in Morgantown, WV, was undertaken in 2004 to characterize the structural and functional attributes of this forest resource. The assessment revealed that this city has about 658,000 trees with canopies that cover 35.5 percent of the area. The most common tree species are sugar maple, black cherry, and hawthorn. The urban forest...

  18. Simulating ungulate herbivory across forest landscapes: A browsing extension for LANDIS-II

    Science.gov (United States)

    Nathan R. De Jager; Patrick J. Drohan; Brian M. Miranda; Brian R. Sturtevant; Susan L. Stout; Alejandro A. Royo; Eric J. Gustafson; Mark C. Romanski

    2017-01-01

    Browsing ungulates alter forest productivity and vegetation succession through selective foraging onspecies that often dominate early succession. However, the long-term and large-scale effects of browsing on forest succession are not possible to project without the use of simulation models. To explore the effects of ungulates on succession in a spatially explicit...

  19. Air pollution: worldwide effects on mountain forests

    Science.gov (United States)

    Anne M. Rosenthal; Andrzej Featured: Bytnerowicz

    2004-01-01

    Widespread forest decline in remote areas of the Carpathian Mountains has been linked to air pollution from urban and industrial regions. Besides injuring plant tissues directly, pollutants may deposit to soils and water, drastically changing susceptible ecosystems. Researcher Andrzej Bytnerowicz has developed effective methods for assessing air quality over wildlands...

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

    Science.gov (United States)

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

    2017-12-01

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

  1. Spatial metrics effect of forest fragmentation on forest bird ...

    African Journals Online (AJOL)

    In this study, relationship between forest patch size and isolation with abundance and occupancy probability of forest-dependent birds was investigated. This study was based within a coastal landscape that faces deleterious human activities such as clearing for agriculture. The study aimed to answer the question of ...

  2. THE FOREST-ATMOSPHERIC CARBON TRANSFER AND STORAGE-II (FACTS-II): ASPEN FACE PROJECT

    Energy Technology Data Exchange (ETDEWEB)

    KARNOSKY,D.F.; HENDREY,G.; PREGITZER,K.; ISEBRANDS,J.G.

    1998-02-01

    The FACTS II (ASPEN FACE) infrastructure including 12 FACE [Free-Air Carbon dioxide Enrichment] rings, a central control facility, a central CO{sub 2} and O{sub 2} receiving and storage area, a central O{sub 3} generation system, and a dispensing system for CO{sub 2} and O{sub 3} was completed in 1997. The FACE rings were planted with over 10,000 plants (aspen, birch and maple). The entire system was thoroughly tested for both CO{sub 2} and O{sub 3} and was shown to be effective in delivering elevated CO{sub 2} and/or O{sub 3} on demand and at predetermined set points. The NCASI support to date has been extremely helpful in matching support for federal grants.

  3. The Forest-Atmospheric Carbon Transfer and Storage-II (FACTS-II): Aspen FACE project

    Energy Technology Data Exchange (ETDEWEB)

    Karnosky, D.F.; Pregitzer, K. [Michigan Technological Univ., Houghton, MI (United States). School of Forestry and Wood Products; Hendrey, G. [Brookhaven National Lab., Upton, NY (United States); Isebrands, J.G. [Forest Service, Rhinelander, WI (United States)

    1998-02-01

    The FACTS II (Aspen FACE) infrastructure including 12 FACE rings, a central control facility, a central CO{sub 2} and O{sub 3} receiving and storage area, a central O{sub 3} generation system, and a dispensing system for CO{sub 2} and O{sub 3} was completed in 1997. The FACE rings were planted with over 10,000 plants (aspen, birch and maple). The entire system was thoroughly tested for both CO{sub 2} and O{sub 3} and was shown to be effective in delivering elevated CO{sub 2} and/or O{sub 3} on demand and at predetermined set points. The NCASI support to date has been extremely helpful in matching support for federal grants.

  4. Effects of wastewater on forested wetlands

    Science.gov (United States)

    Doyle, Thomas W.

    2002-01-01

    Cycling nutrient-enriched wastewater from holding ponds through natural, forested wetlands is a practice that municipal waste treatment managers are considering as a viable option for disposing of wastewater. In this wastewater cycling process, sewer effluent that has been circulated through aerated ponds is discharged into neighboring wetland systems. To understand how wastewater cycling affects forest and species productivity, researchers at the USGS National Wetlands Research Center conducted dendroecological investigations in a swamp system and in a bog system that have been exposed to wastewater effluent for many decades. Dendroecology involves the study of forest changes over time as interpreted from tree rings. Tree-ring chronologies describe the pattern and history of growth suppression and release that can be associated with aging and disturbances such as hurricanes, floods, and fires. But because of limited monitoring, little is known about the potential for long-term effects on forested wetlands as a result of wastewater flooding. USGS researchers used tree rings to detect the effect of wastewater cycling on tree growth. Scientists expected to find that tree-ring width would be increased as a result of added nutrients.

  5. Do rising temperatures always increase forest productivity? Interacting effects of temperature, precipitation, cloudiness and soil texture on tree species growth and competition

    Science.gov (United States)

    Eric J. Gustafson; Brian R. Miranda; Arjan M.G. De Bruijn; Brian R. Sturtevant; Mark E. Kubiske

    2017-01-01

    Forest landscape models (FLM) are increasingly used to project the effects of climate change on forested landscapes, yet most use phenomenological approaches with untested assumptions about future forest dynamics. We used a FLM that relies on first principles to mechanistically simulate growth (LANDIS-II with PnET-Succession) to systematically explore how landscapes...

  6. Forest Health Monitoring and Forest Inventory Analysis programs monitor climate change effects in forest ecosystems

    Science.gov (United States)

    Kenneth W. Stolte

    2001-01-01

    The Forest Health Monitoring (FHM) and Forest Inventory and Analyses (FIA) programs are integrated bilogical monitoring systems that use nationally standardized methods to evaluate and report on the health and sustainability of forest ecosystems in the United States. Many of the anticipated changes in forest ecosystems from climate change were also issues addressed in...

  7. Analyzing the edge effects in a Brazilian seasonally dry tropical forest.

    Science.gov (United States)

    Arruda, D M; Eisenlohr, P V

    2016-02-01

    Due to the deciduous nature of dry forests (widely known as seasonally dry tropical forests) they are subject to microclimatic conditions not experienced in other forest formations. Close examinations of the theory of edge effects in dry forests are still rare and a number of questions arise in terms of this topic. In light of this situation we examined a fragment of the dry forest to respond to the following questions: (I) Are there differences in canopy cover along the edge-interior gradient during the dry season? (II) How does the microclimate (air temperature, soil temperature, and relative humidity) vary along that gradient? (III) How does the microclimate influence tree species richness, evenness and abundance along that gradient? (IV) Are certain tree species more dominant closer to the forest edges? Regressions were performed to address these questions. Their coefficients did not significantly vary from zero. Apparently, the uniform openness of the forest canopy caused a homogeneous internal microclimate, without significant differentiation in habitats that would allow modifications in biotic variables tested. We conclude that the processes of edge effect commonly seen in humid forests, not was shared with the dry forest assessed.

  8. Fragmentation impairs the microclimate buffering effect of tropical forests.

    Science.gov (United States)

    Ewers, Robert M; Banks-Leite, Cristina

    2013-01-01

    Tropical forest species are among the most sensitive to changing climatic conditions, and the forest they inhabit helps to buffer their microclimate from the variable climatic conditions outside the forest. However, habitat fragmentation and edge effects exposes vegetation to outside microclimatic conditions, thereby reducing the ability of the forest to buffer climatic variation. In this paper, we ask what proportion of forest in a fragmented ecosystem is impacted by altered microclimate conditions driven by edge effects, and extrapolate these results to the whole Atlantic Forest biome, one of the most disturbed biodiversity hotspots. To address these questions, we collected above and below ground temperature for a full year using temperature sensors placed in forest fragments of different sizes, and at different distances from the forest edge. In the Atlantic forests of Brazil, we found that the buffering effect of forests reduced maximum outside temperatures by one third or more at ground level within a forest, with the buffering effect being stronger below-ground than one metre above-ground. The temperature buffering effect of forests was, however, reduced near forest edges with the edge effect extending up to 20 m inside the forest. The heavily fragmented nature of the Brazilian Atlantic forest means that 12% of the remaining biome experiences altered microclimate conditions. Our results add further information about the extent of edge effects in the Atlantic Forest, and we suggest that maintaining a low perimeter-to-area ratio may be a judicious method for minimizing the amount of forest area that experiences altered microclimatic conditions in this ecosystem.

  9. Effects of emerald ash borer (Agrilus planipennis) on forest ecosystems

    Science.gov (United States)

    Kathleen S. Knight; Robert P. Long; Joanne Rebbeck; Daniel A. Herms; John Cardina; Catherine P. Herms; Kamal J.K. Gandhi; Annemarie Smith; Kyle C. Costilow; Lawrence C. Long; David L. Cappaert

    2010-01-01

    The effects of emerald ash borer (EAB) (Agrilus planipennis Fairmare) on forest ecosystems are being studied through a collaborative research program involving U.S. Forest Service Northern Research Station (Research...

  10. Forest fires prevention and limitation of the greenhouse effect

    Directory of Open Access Journals (Sweden)

    2005-01-01

    Full Text Available The contribution of forest fires to the carbon budget and greenhouse effect is examined at global and national (Italian scale and forest management options directed to preventing fires are briefly outlined.

  11. Advances of Air Pollution Science: From Forest Decline to Multiple-Stress Effects on Forest Ecosystem Services

    Science.gov (United States)

    E. Paoletti; M. Schaub; R. Matyssek; G. Wieser; A. Augustaitis; A. M. Bastrup-Birk; A. Bytnerowicz; M. S. Gunthardt-Goerg; G. Muller-Starck; Y. Serengil

    2010-01-01

    Over the past 20 years, the focus of forest science on air pollution has moved from forest decline to a holistic framework of forest health, and from the effects on forest production to the ecosystem services provided by forest ecosystems. Hence, future research should focus on the interacting factorial impacts and resulting antagonistic and synergistic responses of...

  12. Forests

    Science.gov (United States)

    Louis R. Iverson; Mark W. Schwartz

    1994-01-01

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

  13. Simulating the cumulative effects of multiple forest management strategies on landscape measures of forest sustainability

    Science.gov (United States)

    Eric J. Gustafson; David E. Lytle; Randy Swaty; Craig Loehle

    2007-01-01

    While the cumulative effects of the actions of multiple owners have long been recognized as critically relevant to efforts to maintain sustainable forests at the landscape scale, few studies have addressed these effects. We used the HARVEST timber harvest simulator to predict the cumulative effects of four owner groups (two paper companies, a state forest and non-...

  14. When you cannot see the forest for the trees: Effect of forest monocultures on biodiversity conservation

    International Nuclear Information System (INIS)

    Cordero Rivera, Adolfo

    2011-01-01

    Human population is growing at rates that were unimaginable only a century ago, creating such pressure on resources, which will only decrease when the decline in birth rate stabilizes population. Among these resources, wood is one of the most demanded. Global consumption of wood is currently more than 3500 million m 3, a rate multiplied by six since 1950. To meet this demand, we manage millions of hectares of forests and forest plantations, part of which are cut down each year. This logging determines drastic effects on forests, affecting the biodiversity associated and the ecosystems services provided to society. This work is a review of the structural and functional characteristics that differentiate forests and forest plantations, in spite of the confusion between both ecosystems by FAO and the forest sector companies, which have coined the oxymoron planted forests. Forest plantations are more productive than forests from the point of view of the volume of wood that can be obtained from them, and if well managed, could minimize the pressure on forests. However, they do not provide many services that forests do provide, especially in the case of monospecific plantations consisting of even aged individuals of exotic species that are managed intensively. Some of the many techniques that combine the production of wood with the conservation of biodiversity are reviewed.

  15. Effectiveness of Vegetation in Erosion Control From Forest Road Sideslopes

    Science.gov (United States)

    Johnny M. Grace

    2002-01-01

    Abstract.. Forest roads have been identified as the major contributor to sediment production from forested lands, accounting for perhaps as much as 90% of all sediment produced. In recent years, increased concern and societal pressure has focused on the impacts of forest roads and the effectiveness of erosion control measures. In addition, the re–...

  16. Initial effects of restoring natural forest structures in Estonia

    Science.gov (United States)

    D. Laarmann; H. Korjus; A. Sims; A. Kangur; J.A. Stanturf

    2013-01-01

    The legacy of structural homogenization due to forest management for commercial products is a loss of biodiversity. A common policy in many European countries is to increase forest diversity by converting managed forests to more natural conditions. The aim of this study was to provide an early evaluation of the effectiveness of different restoration treatments to...

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

    Science.gov (United States)

    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. Variable effects of climate on forest growth in relation to climate extremes, disturbance, and forest dynamics

    Science.gov (United States)

    Itter, Malcolm S.; Finley, Andrew O.; D'Amato, Anthony W.; Foster, Jane R.; Bradford, John B.

    2017-01-01

    Changes in the frequency, duration, and severity of climate extremes are forecast to occur under global climate change. The impacts of climate extremes on forest productivity and health remain difficult to predict due to potential interactions with disturbance events and forest dynamics—changes in forest stand composition, density, size and age structure over time. Such interactions may lead to non-linear forest growth responses to climate involving thresholds and lag effects. Understanding how forest dynamics influence growth responses to climate is particularly important given stand structure and composition can be modified through management to increase forest resistance and resilience to climate change. To inform such adaptive management, we develop a hierarchical Bayesian state space model in which climate effects on tree growth are allowed to vary over time and in relation to past climate extremes, disturbance events, and forest dynamics. The model is an important step toward integrating disturbance and forest dynamics into predictions of forest growth responses to climate extremes. We apply the model to a dendrochronology data set from forest stands of varying composition, structure, and development stage in northeastern Minnesota that have experienced extreme climate years and forest tent caterpillar defoliation events. Mean forest growth was most sensitive to water balance variables representing climatic water deficit. Forest growth responses to water deficit were partitioned into responses driven by climatic threshold exceedances and interactions with insect defoliation. Forest growth was both resistant and resilient to climate extremes with the majority of forest growth responses occurring after multiple climatic threshold exceedances across seasons and years. Interactions between climate and disturbance were observed in a subset of years with insect defoliation increasing forest growth sensitivity to water availability. Forest growth was particularly

  19. The Effects of Different Forest Loggings on Forest Birds Community Composition in Shastkolateh Forest, Gorgan

    Directory of Open Access Journals (Sweden)

    F. Parsaei

    2014-06-01

    Full Text Available The species composition of a bird community is dependent upon many factors. Within any geographic area, vegetation structure may be the most important factor. The changes of bird community composition based on foraging behavior in relation to 3 different harvesting systems, including strip cutting, group selection logging, and single tree selection logging, was evaluated in a virgin area in this study. Birds and environmental variables were detected within 103 circle sampling plots with 25m radius. Based on the results, 4 groups of birds were observed in treatments based on the foraging behavior. Group 1 was ground foragers, group 2 consisted of foliage gleaning, group 3 included flycatchers, and group 4 represented bark foraging. The first group had the highest abundance in the strip treatment. The second group in group selection treatment, and the third and fourth groups had the highest abundance in the virgin area and then, in single tree selection treatment. The first group showed the highest correlation with shrub and herb or grass layer, stone cover and the number of trees 10-20m in height. The second, third and fourth groups showed the highest correlation with the number of trees>20m in height, basal areas, dead trees number, and the number of fagus trees. The results showed the single cutting treatment had a relatively minor effect on mature forest bird species and were more appropriate and sustainable methods to reduce the negative effects of forest harvesting on the birds.

  20. Assessing urban forest effects and values, Chicago's urban forest

    Science.gov (United States)

    David J. Nowak; Robert E. III Hoehn; Daniel E. Crane; Jack C. Stevens; Cherie Leblanc Fisher

    2010-01-01

    An analysis of trees in Chicago, IL, reveals that this city has about 3,585,000 trees with canopies that cover 17.2 percent of the area. The most common tree species are white ash, mulberry species, green ash, and tree-of-heaven. Chicago's urban forest currently stores about 716,000 tons of carbon...

  1. Assessing urban forest effects and values, Minneapolis' urban forest

    Science.gov (United States)

    David J. Nowak; Robert E. III Hoehn; Daniel E. Crane; Jack C. Stevens; Jeffrey T. Walton

    2006-01-01

    An analysis of trees in Minneapolis, MN, reveals that the city has about 979,000 trees with canopies that cover 26.4 percent of the area. The most common tree species are green ash, American elm, and boxelder. The urban forest currently stores about 250,000 tons of carbon valued at $4.6 million. In addition, these trees remove about 8,900 tons of carbon per year ($164,...

  2. Assessing urban forest effects and values, Philladelphia's urban forest

    Science.gov (United States)

    David J. Nowak; Robert E., III Hoehn; Daniel E. Crane; Jack C. Stevens; Jeffrey T. Walton

    2007-01-01

    An analysis of trees in Philadelphia reveals that this city has about 2.1 million trees with canopies that cover 15.7 percent of the area. The most common tree species are black cherry, crabapple, and tree of heaven. The urban forest currently stores about 530,000 tons of carbon valued at $9.8 million. In addition, these trees remove about 16,100 tons of carbon per...

  3. Assessing urban forest effects and values, San Francisco's urban forest

    Science.gov (United States)

    David J. Nowak; Robert E., III Hoehn; Daniel E. Crane; Jack C. Stevens; Jeffrey T. Walton

    2007-01-01

    An analysis of trees in San Francisco, CA reveals that this city has about 669,000 trees with canopies that cover 11.9 percent of the area. The most common tree species are blue gum eucalyptus, Monterey pine, and Monterey cypress. The urban forest currently stores about 196,000 tons of carbon valued at $3.6 million. In addition, these trees remove about 5,200 tons of...

  4. Assessing urban forest effects and values, Casper's urban forest

    Science.gov (United States)

    David J. Nowak; Robert E., III Hoehn; Daniel E. Crane; Jack C. Stevens; Jeffrey T. Walton

    2006-01-01

    An analysis of trees in Casper, WY reveals that this city has about 123,000 trees with canopies that cover 8.9 percent of the area. The most common tree species are plains cottonwood, blue spruce, and American elm. The urban forest currently store about 37,000 tons of carbon valued at $689,000. In addition, these trees remove about 1,200 tons of carbon per year ($22,...

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

    Science.gov (United States)

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

    2010-01-01

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

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

    Science.gov (United States)

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

    2013-01-01

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

  7. Competition effects in an afrotemperate forest

    Directory of Open Access Journals (Sweden)

    Thomas Seifert

    2014-09-01

    Full Text Available Background Information about competition responses is mainly available for monospecific stands or mixed stands with a small number of species. Studies on complex multi-species and highly structured forest ecosystems are scarce. Accordingly, the objective of this study was to quantify competition effects and analyse competition responses in a species-diverse afrotemperate forest in South Africa, based on an observational study with mapped tree positions and long-term diameter increment records. Methods The sensitivity to competition was analysed for individual species and involved the calculation of the slope of the linear relation between the value of a competition index (CI and diameter growth as a measure of sensitivity. In a next step different competition indices were combined and tree diameters were grouped in three classes as surrogates for canopy status and ontogenetic stage. Results Five competition indices were found to be effective in showing sensitivity to competition for a number of canopy and sub-canopy species. Significant linear regressions were fitted for 18 of a total of 25 species. Species reactions varied significantly in their sensitivity to the different CIs. The indices were classified as belonging to two groups, those that responded more to local crowding and those that are more sensitive to overtopping, which revealed species-specific sensitivities to both factors. The analysis based on diameter classes revealed that species clearly changed their sensitivity to crowding or overtopping depending on diameter. Canopy and sub-canopy species showed distinct differences in their reactions. Conclusions The application of multiple CIs brought novel insights relating to the dynamics of afrotemperate forests. The response patterns to different competition indices that focus on crowding and overtopping are varied and tree diameter dependent, indicating that oversimplified assumptions are not warranted in the interpretation of CI

  8. Forests and water: effects of forest management on floods, sedimentation, and water supply

    Science.gov (United States)

    Henry W. Anderson; Marvin D. Hoover; Kenneth G. Reinhart

    1976-01-01

    From the background of more than 100 years' collective experience in watershed research and from comprehensive review of the literature of forest hydrology, the authors summarize what is known about the forest's influence on the water resource, particularly the effects of current forestry practices. They first examine the fundamental hydrologic processes in...

  9. GIS based Cadastral level Forest Information System using World View-II data in Bir Hisar (Haryana)

    Science.gov (United States)

    Mothi Kumar, K. E.; Singh, S.; Attri, P.; Kumar, R.; Kumar, A.; Sarika; Hooda, R. S.; Sapra, R. K.; Garg, V.; Kumar, V.; Nivedita

    2014-11-01

    Identification and demarcation of Forest lands on the ground remains a major challenge in Forest administration and management. Cadastral forest mapping deals with forestlands boundary delineation and their associated characterization (forest/non forest). The present study is an application of high resolution World View-II data for digitization of Protected Forest boundary at cadastral level with integration of Records of Right (ROR) data. Cadastral vector data was generated by digitization of spatial data using scanned mussavies in ArcGIS environment. Ortho-images were created from World View-II digital stereo data with Universal Transverse Mercator coordinate system with WGS 84 datum. Cadastral vector data of Bir Hisar (Hisar district, Haryana) and adjacent villages was spatially adjusted over ortho-image using ArcGIS software. Edge matching of village boundaries was done with respect to khasra boundaries of individual village. The notified forest grids were identified on ortho-image and grid vector data was extracted from georeferenced cadastral data. Cadastral forest boundary vectors were digitized from ortho-images. Accuracy of cadastral data was checked by comparison of randomly selected geo-coordinates points, tie lines and boundary measurements of randomly selected parcels generated from image data set with that of actual field measurements. Area comparison was done between cadastral map area, the image map area and RoR area. The area covered under Protected Forest was compared with ROR data and within an accuracy of less than 1 % from ROR area was accepted. The methodology presented in this paper is useful to update the cadastral forest maps. The produced GIS databases and large-scale Forest Maps may serve as a data foundation towards a land register of forests. The study introduces the use of very high resolution satellite data to develop a method for cadastral surveying through on - screen digitization in a less time as compared to the old fashioned

  10. Analysis of Edge Effects on Fragmented Forests Using Forest Inventories in Southwestern Amazonia

    Science.gov (United States)

    Numata, I.; Silva, S.; Cochrane, M. A.

    2015-12-01

    Deforestation fragments contiguous forests into smaller and smaller pieces, inducing ecological and biological changes in forest ecosystems. Edge effects are spatial and temporal phenomena. The effects of forest fragmentation vary primarily as functions of edge penetration distance, spatial arrangements and time of persistence of forest edges. Across varying penetration distances in a forest edge, numerous changes occur including elevated tree mortality and canopy desiccation, changes in forest structure and species composition, alternation of hydrological and carbon cycles. We analyzed the effects of edge penetration distance and time of persistence of forest edges on forest biophysical characteristics based upon more than thirty 500m transects over highly fragmented forests in Acre, the southwestern Amazon. Spatial variability of tree data (diameter at breast height - DBH, above ground biomass, tree density, species composition and population) was measured along a penetration distance of 500m from forest edges. Different edge age classes (1-5yr, 6-10yr, > 10yr) and edge penetration distances were identified based upon a Landsat time-series analysis. The number of individual plants with DBH > 10cm tends to be greater near edge (largest in the first 100m), while larger biomass amounts are found at > 300m distance. The impact of penetration distance on biomass, however, is not statistically significant. In terms of the distribution of DBHs, while smaller trees with DBH trees, larger DBH trees tend to increase after 300m penetration distance. The effect of edge persistence period (edge age) is not significant for both the number of individual plants as well as the biomass, however it is more pronounced on secondary species' biomass such as Cecrcopia sp and bamboo, which increase as edges persist longer.

  11. Effectiveness of Africa's tropical protected areas for maintaining forest cover.

    Science.gov (United States)

    Bowker, J N; De Vos, A; Ament, J M; Cumming, G S

    2017-06-01

    The effectiveness of parks for forest conservation is widely debated in Africa, where increasing human pressure, insufficient funding, and lack of management capacity frequently place significant demands on forests. Tropical forests house a substantial portion of the world's remaining biodiversity and are heavily affected by anthropogenic activity. We analyzed park effectiveness at the individual (224 parks) and national (23 countries) level across Africa by comparing the extent of forest loss (as a proxy for deforestation) inside parks to matched unprotected control sites. Although significant geographical variation existed among parks, the majority of African parks had significantly less forest loss within their boundaries (e.g., Mahale Park had 34 times less forest loss within its boundary) than control sites. Accessibility was a significant driver of forest loss. Relatively inaccessible areas had a higher probability (odds ratio >1, p < 0.001) of forest loss but only in ineffective parks, and relatively accessible areas had a higher probability of forest loss but only in effective parks. Smaller parks less effectively prevented forest loss inside park boundaries than larger parks (T = -2.32, p < 0.05), and older parks less effectively prevented forest loss inside park boundaries than younger parks (F 2,154 = -4.11, p < 0.001). Our analyses, the first individual and national assessment of park effectiveness across Africa, demonstrated the complexity of factors (such as geographical variation, accessibility, and park size and age) influencing the ability of a park to curb forest loss within its boundaries. © 2016 Society for Conservation Biology.

  12. The effect of protected areas on forest disturbance in the Carpathian Mountains 1985-2010.

    Science.gov (United States)

    Butsic, Van; Munteanu, Catalina; Griffiths, Patrick; Knorn, Jan; Radeloff, Volker C; Lieskovský, Juraj; Mueller, Daniel; Kuemmerle, Tobias

    2017-06-01

    Protected areas are a cornerstone for forest protection, but they are not always effective during times of socioeconomic and institutional crises. The Carpathian Mountains in Eastern Europe are an ecologically outstanding region, with widespread seminatural and old-growth forest. Since 1990, Carpathian countries (Czech Republic, Hungary, Poland, Romania, Slovakia, and Ukraine) have experienced economic hardship and institutional changes, including the breakdown of socialism, European Union accession, and a rapid expansion of protected areas. The question is how protected-area effectiveness has varied during these times across the Carpathians given these changes. We analyzed a satellite-based data set of forest disturbance (i.e., forest loss due to harvesting or natural disturbances) from 1985 to 2010 and used matching statistics and a fixed-effects estimator to quantify the effect of protection on forest disturbance. Protected areas in the Czech Republic, Slovakia, and the Ukraine had significantly less deforestation inside protected areas than outside in some periods; the likelihood of disturbance was reduced by 1-5%. The effectiveness of protection increased over time in these countries, whereas the opposite was true in Romania. Older protected areas were most effective in Romania and Hungary, but newer protected areas were more effective in Czech Republic, and Poland. Strict protection (International Union for Conservation of Nature [IUCN] protection category Ia-II) was not more effective than landscape-level protection (IUCN III-VI). We suggest that the strength of institutions, the differences in forest privatization, forest management, prior distribution of protected areas, and when countries joined the European Union may provide explanations for the strikingly heterogeneous effectiveness patterns among countries. Our results highlight how different the effects of protected areas can be at broad scales, indicating that the effectiveness of protected areas is

  13. Modeling the cumulative watershed effects of forest management strategies

    Science.gov (United States)

    R. R. Ziemer; J. Lewis; R. M. Rice; T. E. Lisle

    1991-01-01

    Abstract - There is increasing concern over the possibility of adverse cumulative watershed effects from intensive forest management. It is impractical to address many aspects of the problem experimentally because to do so would require studying large watersheds for 100 yr or more. One such aspect is the long-term effect of forest management strategies on erosion and...

  14. Effect of fragmentation on the Costa Rican dry forest avifauna.

    Science.gov (United States)

    Barrantes, Gilbert; Ocampo, Diego; Ramírez-Fernández, José D; Fuchs, Eric J

    2016-01-01

    Deforestation and changes in land use have reduced the tropical dry forest to isolated forest patches in northwestern Costa Rica. We examined the effect of patch area and length of the dry season on nestedness of the entire avian community, forest fragment assemblages, and species occupancy across fragments for the entire native avifauna, and for a subset of forest dependent species. Species richness was independent of both fragment area and distance between fragments. Similarity in bird community composition between patches was related to habitat structure; fragments with similar forest structure have more similar avian assemblages. Size of forest patches influenced nestedness of the bird community and species occupancy, but not nestedness of assemblages across patches in northwestern Costa Rican avifauna. Forest dependent species (species that require large tracts of mature forest) and assemblages of these species were nested within patches ordered by a gradient of seasonality, and only occupancy of species was nested by area of patches. Thus, forest patches with a shorter dry season include more forest dependent species.

  15. Effects of coffee management on deforestation rates and forest integrity.

    Science.gov (United States)

    Hylander, Kristoffer; Nemomissa, Sileshi; Delrue, Josefien; Enkosa, Woldeyohannes

    2013-10-01

    Knowledge about how forest margins are utilized can be crucial for a general understanding of changes in forest cover, forest structure, and biodiversity across landscapes. We studied forest-agriculture transitions in southwestern Ethiopia and hypothesized that the presence of coffee (Coffea arabica)decreases deforestation rates because of coffee's importance to local economies and its widespread occurrence in forests and forest margins. Using satellite images and elevation data, we compared changes in forest cover over 37 years (1973-2010) across elevations in 2 forest-agriculture mosaic landscapes (1100 km(2) around Bonga and 3000 km(2) in Goma-Gera). In the field in the Bonga area, we determined coffee cover and forest structure in 40 forest margins that differed in time since deforestation. Both the absolute and relative deforestation rates were lower at coffee-growing elevations compared with at higher elevations (-10/20% vs. -40/50% comparing relative rates at 1800 m asl and 2300-2500 m asl, respectively). Within the coffee-growing elevation, the proportion of sites with high coffee cover (>20%) was significantly higher in stable margins (42% of sites that had been in the same location for the entire period) than in recently changed margins (0% of sites where expansion of annual crops had changed the margin). Disturbance level and forest structure did not differ between sites with 30% or 3% coffee. However, a growing body of literature on gradients of coffee management in Ethiopia reports coffee's negative effects on abundances of forest-specialist species. Even if the presence of coffee slows down the conversion of forest to annual-crop agriculture, there is a risk that an intensification of coffee management will still threaten forest biodiversity, including the genetic diversity of wild coffee. Conservation policy for Ethiopian forests thus needs to develop strategies that acknowledge that forests without coffee production may have higher deforestation

  16. Forest fragmentation and its effects on birds

    Science.gov (United States)

    Robbins, C.S.; Johnson, James E.

    1988-01-01

    Fragmentation of forest land, whether by suburban development, highways, transmission lines, or poorly planned cutting regimes, seriously affects reproduction by the large numbers of obligate forest interior birds. Many of our warblers, vireos, thrushes, tanagers, and flycatchers are highly migratory insectivorous birds that spend more than half the year in the neotropics, but migrate north to the United States and Canada to rear their young. These tropical visitors are especially vulnerable to predation and cowbird parasitism and are unable to maintain their populations within 100-200 m of forest edge. Habitats for these declining species can be provided by managing forest lands in large blocks so as to maintain at all times extensive contiguous areas of successional stages as well as of mature forest. Avoiding scattered small cuts will also help by reducing edge, road construction, and other disturbance.

  17. The effects of forest destruction on the abundance, species richness ...

    African Journals Online (AJOL)

    SARAH

    2013-04-25

    Apr 25, 2013 ... The effects of forest destruction on the abundance, species richness and diversity of butterflies in the. Bosomkese Forest Reserve, Brong Ahafo Region,. Ghana. Addai, G. and Baidoo P. K*. Department of Theoretical and Applied Biology, Kwame Nkrumah University of Science and Technology,. Kumasi ...

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

    Science.gov (United States)

    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. © 2014 Society for Conservation Biology.

  19. Model-based assessments of climate change effects on forests

    Energy Technology Data Exchange (ETDEWEB)

    Loehle, C.; LeBlanc, D.C. [Argonne National Lab., IL (United States)]|[Ball State Univ., Muncie, IN (United States)

    1995-06-01

    The potential effects of climate change on forests are of increasing concern. A number of studies based on forest simulation models predict substantial alteration of forest composition, forest dieback, or even loss of forest cover in response to increased temperatures associated with increasing atmospheric carbon dioxide concentrations. However, the structure of these computer models may cause them to overemphasize the role of climate in controlling tree growth and mortality. Model functions that represent the influence of climate on tree growth are based on the geographic range limits of a species, predicting maximal growth in the center of the range and zero growth (100% mortality) at the range limits and beyond. Many tree species can survive in climatic conditions outside their present range limits and can tolerate widely fluctuating climate regimes. Hence, there is reason to suspect that published projections of forest responses to climate change may exaggerate the direct impact of climate on tree growth and mortality. We propose that forest simulation models be reformulated with more realistic representations of growth responses to temperature, moisture, mortality and dispersal. We believe that only when these models more accurately reflect the physiological bases of the responses of tree species to climate variables can they be used to simulate responses of forests to rapid changes in climate. We argue that direct forest responses to climate change projected by such a reformulated model may be less traumatic and more gradual than those projected by current models.

  20. Effect of Cu(II), Cd(II) and Zn(II) on Pb(II) biosorption by algae Gelidium-derived materials.

    Science.gov (United States)

    Vilar, Vítor J P; Botelho, Cidália M S; Boaventura, Rui A R

    2008-06-15

    Biosorption of Pb(II), Cu(II), Cd(II) and Zn(II) from binary metal solutions onto the algae Gelidium sesquipedale, an algal industrial waste and a waste-based composite material was investigated at pH 5.3, in a batch system. Binary Pb(II)/Cu(II), Pb(II)/Cd(II) and Pb(II)/Zn(II) solutions have been tested. For the same equilibrium concentrations of both metal ions (1 mmol l(-1)), approximately 66, 85 and 86% of the total uptake capacity of the biosorbents is taken by lead ions in the systems Pb(II)/Cu(II), Pb(II)/Cd(II) and Pb(II)/Zn(II), respectively. Two-metal results were fitted to a discrete and a continuous model, showing the inhibition of the primary metal biosorption by the co-cation. The model parameters suggest that Cd(II) and Zn(II) have the same decreasing effect on the Pb(II) uptake capacity. The uptake of Pb(II) was highly sensitive to the presence of Cu(II). From the discrete model it was possible to obtain the Langmuir affinity constant for Pb(II) biosorption. The presence of the co-cations decreases the apparent affinity of Pb(II). The experimental results were successfully fitted by the continuous model, at different pH values, for each biosorbent. The following sequence for the equilibrium affinity constants was found: Pb>Cu>Cd approximately Zn.

  1. Effects of forest expansion on mountain grassland

    DEFF Research Database (Denmark)

    Guidi, Claudia; Magid, Jakob; Rodeghiero, Mirco

    2014-01-01

    Background and aims. Grassland abandonment followed by forest succession is the dominant land-use change in the European Alps. We studied the impact of current forest expansion on mountain grassland on changes in physical soil organic carbon (SOC) fractions along a land-use and management gradient......, focusing on changes in aggregate stability and particulate organic matter (POM). Methods. Four successional stages were investigated: managed grassland, two transitional phases in which grassland abandonment led to colonization by Picea abies (L.) Karst., and old mixed forest dominated by Fagus sylvatica L...

  2. Effect of forest on sediment yield in North China

    Directory of Open Access Journals (Sweden)

    Yu Xinxiao Prof.

    2013-06-01

    Full Text Available Forest-sediment relationship is a hot and important issue in Ecohydrology studies. China has implemented many large-scale reforestation programmes in the last decades to address the growing soil erosion and desertification. In this study, we made statistical and graphic analyses on the long-term hydrological data of the 39 watersheds in the rocky mountain area of the North China, and then we were able to analyze the effect of forest on sediment yield. Our results show that the effect is weak in the lees-precipitation regions (when MAP 500 mm, the impact of forest on reducing sediment yield is different with the varied forest coverage (f, the relationship between the sediment yield and forest coverage show a quadratic polynomial.

  3. Advances of air pollution science: from forest decline to multiple-stress effects on forest ecosystem services.

    Science.gov (United States)

    Paoletti, E; Schaub, M; Matyssek, R; Wieser, G; Augustaitis, A; Bastrup-Birk, A M; Bytnerowicz, A; Günthardt-Goerg, M S; Müller-Starck, G; Serengil, Y

    2010-06-01

    Over the past 20 years, the focus of forest science on air pollution has moved from forest decline to a holistic framework of forest health, and from the effects on forest production to the ecosystem services provided by forest ecosystems. Hence, future research should focus on the interacting factorial impacts and resulting antagonistic and synergistic responses of forest trees and ecosystems. The synergistic effects of air pollution and climatic changes, in particular elevated ozone, altered nitrogen, carbon and water availability, must be key issues for research. Present evidence suggests air pollution will become increasingly harmful to forests under climate change, which requires integration amongst various stressors (abiotic and biotic factors, including competition, parasites and fire), effects on forest services (production, biodiversity protection, soil protection, sustained water balance, socio-economical relevance) and assessment approaches (research, monitoring, modeling) to be fostered. Copyright 2009 Elsevier Ltd. All rights reserved.

  4. Mines, prospects, and mineral sites, wilderness and RARE II areas, White Mountain National Forest, New Hampshire

    Science.gov (United States)

    Gazdik, G. C.; Harris, Gazdik; Welsh, R. A.; Girol, V. P.

    1988-01-01

    The Wilderness Act (Public Law 88-577, September 3, 1964) and related acts require the U.S. Geological Survey and the U.S. Bureau of Mines to survey certain areas on Federal lands to determine their mineral value, if any, that may be present. Results must be made available to the public and be submitted to the President and the Congress. This report presents the results of investigations of mines, prospects, and mineral sites in the Great Gulf and Presidential Range-Dry River Wilderness Areas; the Dartmouth Range, Wild River, Pemigewasset, Kinsman Mountain, Mount Wolf-Gordon Pond, Jobildunk, and Carr Mountain Roadless Areas; and the intervening and immediately surrounding areas in the White Mountain National Forest, Coos, Grafton, and Carroll Counties, New Hampshire. The Great Gulf Wilderness was established when the Wilderness Act was passed in 1964, and the Presidential Range-Dry River Wilderness was established by Public Law 93-622, January 3, 1975. The Dartmouth Range, Wild River, Pemigewasset, Kinsman Mountain, Mount Wolf-Gordon Pond, Carr Mountain, and Jobildunk areas were classified as a further planning area during the Second Roadless Area Review and Evaluation (RARE II) by the U.S. Forest Service, January 1979.

  5. Climate change effects on forests: A critical review

    Energy Technology Data Exchange (ETDEWEB)

    Loehle, C. [Argonne National Lab., IL (United States); LeBlanc, D. [Ball State Univ., Muncie, IN (United States). Dept. of Biology

    1996-02-01

    While current projections of future climate change associated with increases in atmospheric greenhouse gases have a high degree of uncertainty, the potential effects of climate change on forests are of increasing concern. A number of studies based on forest simulation models predict substantial temperatures associated with increasing atmospheric carbon dioxide concentrations. However, the structure of these computer models may cause them to overemphasize the role of climate in controlling tree growth and mortality. We propose that forest simulation models be reformulated with more realistic representations of growth responses to temperature, moisture, mortality, and dispersal. We believe that only when these models more accurately reflect the physiological bases of the responses of tree species to climate variables can they be used to simulate responses of forests to rapid changes in climate. We argue that direct forest responses to climate change projected by such a reformulated model may be less traumatic and more gradual than those projected by current models. However, the indirect effects of climate change on forests, mediated by alterations of disturbance regimes or the actions of pests and pathogens, may accelerate climate-induced change in forests, and they deserve further study and inclusion within forest simulation models.

  6. Remote Sensing Techniques in Monitoring Post-Fire Effects and Patterns of Forest Recovery in Boreal Forest Regions: A Review

    Directory of Open Access Journals (Sweden)

    Thuan Chu

    2013-12-01

    Full Text Available The frequency and severity of forest fires, coupled with changes in spatial and temporal precipitation and temperature patterns, are likely to severely affect the characteristics of forest and permafrost patterns in boreal eco-regions. Forest fires, however, are also an ecological factor in how forest ecosystems form and function, as they affect the rate and characteristics of tree recruitment. A better understanding of fire regimes and forest recovery patterns in different environmental and climatic conditions will improve the management of sustainable forests by facilitating the process of forest resilience. Remote sensing has been identified as an effective tool for preventing and monitoring forest fires, as well as being a potential tool for understanding how forest ecosystems respond to them. However, a number of challenges remain before remote sensing practitioners will be able to better understand the effects of forest fires and how vegetation responds afterward. This article attempts to provide a comprehensive review of current research with respect to remotely sensed data and methods used to model post-fire effects and forest recovery patterns in boreal forest regions. The review reveals that remote sensing-based monitoring of post-fire effects and forest recovery patterns in boreal forest regions is not only limited by the gaps in both field data and remotely sensed data, but also the complexity of far-northern fire regimes, climatic conditions and environmental conditions. We expect that the integration of different remotely sensed data coupled with field campaigns can provide an important data source to support the monitoring of post-fire effects and forest recovery patterns. Additionally, the variation and stratification of pre- and post-fire vegetation and environmental conditions should be considered to achieve a reasonable, operational model for monitoring post-fire effects and forest patterns in boreal regions.

  7. Effects of Selected Timber Management Practices on Forest Birds in Missouri Oak-Hickory Forests: Pre-treatment Results

    Science.gov (United States)

    Rich L. Clawson; John Faaborg; Elena. Seon

    1997-01-01

    Our goal is to understand the repercussions of two different forest management techniques on Neotropical migrant birds in the heavily forested landscape of the Missouri Ozarks. Our objectives are to determine breeding densities of forest birds under even-aged and uneven-aged management regimes and to determine the effects of these practices on songbird demographics....

  8. DIRECTIONS FOR EFFECTIVE USE OF FOREST RESOURCES IN UKRAINE

    Directory of Open Access Journals (Sweden)

    Mariana Svyntukh

    2015-11-01

    Full Text Available Purpose. The aim of the article is determination and substantiation of directions of rational use of forest resources in Ukraine. Methodology of research. The theoretical and methodological basis of conducted research is the provision of economic theory, sustainable development, environmental economics and economics forest exploitation. The following methodological tools and techniques were used to achieve this goal: methods of analysis and synthesis (to identify problems of the relationship for using potential of forest resources with factors of influence on their reproduction, the studying essence of the term “forest resources”; monographic – to study the experience of forming rational use of forest resources and wood waste; systematic approach (in substantiating the use of instruments for regulation forest exploitation; scientific abstraction (in the study of capabilities to ensure the process of rational reproduction of forest resources; graphic (for visual images of some analytical observations. Results. Theoretical approach to forest regeneration as a major task in forest anagement, which includes the integrated use of all available organizational and technological measures to facilitate its natural regeneration has been formulated. It has been established the regularity of ensuring the efficient use of waste wood in places of billets, identified and systematized its forms for future use. The methodical approach to assess the effect of using wood waste for fuel production and related products during processing on the harmonization of economic and environmental interests in the area of forest exploitation has been formulated. Practical implications. The obtained results are the basis for solving practical problems of integrated management of forest resources in Ukraine, waste of forest felling in the places of timber harvesting and also for development of the system of measures to improve the ecological and economic mechanism of

  9. Assessment of soil acidification effects on forest growth in Sweden

    International Nuclear Information System (INIS)

    Sverdrup, H.; Warfvinge, P.; Nihlgaard, B.

    1994-01-01

    The results of mapping critical loads, areas where they have been exceeded and steady state (Ca+Mg+K)/Al ratios of soils in Sweden, has been used to assess the order of magnitude of the ecological and economic risks involved with acid deposition for Swedish forests. The results of the calculations indicate that 81% of the Swedish forested area received acid deposition in excess of the critical load at present. Under continued deposition at 1990 level, forest die-back is predicted to occur on approximately 1% of the forested area, and significant growth rate reductions are predicted for 80% of the Swedish forested area. For Sweden, growth losses in the order of 17.5 million m -3 yr -1 are predicted, equivalent to approximately 19% of current growth. Comparable losses can be predicted for other Nordic countries. The soil acidification situation is predicted to deteriorate significantly during the next 5-15 years, unless rapid emission reductions can be achieved. A minimum deposition reduction over Sweden of 95% on sulphur deposition and 30% on the N deposition in relation to 1990 level is required in order to protect 95% of the Swedish forest ecosystems from adverse effects of acidification. A minimum reduction of 60% on sulphur deposition and 30% on the N deposition is required to keep forest harvest at planned levels. 148 refs., 9 figs., 9 tabs

  10. Effects of reduced-impact logging and forest physiognomy on bat populations of lowland Amazonian forest.

    Science.gov (United States)

    Steven J. Presley; Michael R. Willig; Wunderle Jr. Joseph M.; Luis Nélio. Saldanha

    2008-01-01

    1.As human population size increases, demand for natural resources will increase. Logging pressure related to increasing demands continues to threaten remote areas of Amazonian forest. A harvest protocol is required to provide renewable timber resources that meet consumer needs while minimizing negative effects on biodiversity and ecosystem services. Reduced-impact...

  11. Climate and bark beetle effects on forest productivity -- linking dendroecology with forest landscape modeling

    Science.gov (United States)

    Alec M. Kretchun; E. Louise Loudermilk; Robert M. Scheller; Matthew D. Hurteau; Soumaya Belmecheri

    2016-01-01

    In forested systems throughout the world, climate influences tree growth and aboveground net primary productivity (ANPP). The effects of extreme climate events (i.e., drought) on ANPP can be compounded by biotic factors (e.g., insect outbreaks). Understanding the contribution of each of these influences on growth requires information at...

  12. Effects of climate change and shifts in forest composition on forest net primary production

    Science.gov (United States)

    Jyh-Min Chiang; Louts [Louis] R. Iverson; Anantha Prasad; Kim J. Brown

    2008-01-01

    Forests are dynamic in both structure and species composition, and these dynamics are strongly influenced by climate. However, the net effects of future tree species composition on net primary production (NPP) are not well understood. The objective of this work was to model the potential range shifts of tree species (DISTRIB Model) and predict their impacts on NPP (...

  13. Assessing the effects of management alternatives on habitat suitability in a forested landscape of northeastern China.

    Science.gov (United States)

    Longru, Jin; He, Hong S; Yufei, Zhou; Rencang, Bu; Keping, Sun

    2010-05-01

    Forest management often has cumulative, long-lasting effects on wildlife habitat suitability and the effects may be impractical to evaluate using landscape-scale field experiments. To understand such effects, we linked a spatially explicit landscape disturbance and succession model (LANDIS) with habitat suitability index (HSI) models to assess the effects of management alternatives on habitat suitability in a forested landscape of northeastern China. LANDIS was applied to simulate future forest landscape changes under four management alternatives (no cutting, clearcutting, selective cutting I and II) over a 200-year horizon. The simulation outputs were linked with HSI models for three wildlife species, the red squirrel (Sciurus vulgaris), the red deer (Cervus elaphus) and the hazel grouse (Bonasa bonasia). These species are chosen because they represent numerous species that have distinct habitat requirements in our study area. We assessed their habitat suitability based on the mean HSI values, which is a measure of the average habitat quality. Our simulation results showed that no one management scenario was the best for all species and various forest management scenarios would lead to conflicting wildlife habitat outcomes. How to choose a scenario is dependent on the trade-off of economical, ecological and social goals. Our modeling effort could provide decision makers with relative comparisons among management scenarios from the perspective of biodiversity conservation. The general simulation results were expected based on our knowledge of forest management and habitat relationships of the species, which confirmed that the coupled modeling approach correctly simulated the assumed relationships between the wildlife, forest composition, age structure, and spatial configuration of habitat. However, several emergent results revealed the unexpected outcomes that a management scenario may lead to.

  14. Assessing the Effects of Management Alternatives on Habitat Suitability in a Forested Landscape of Northeastern China

    Science.gov (United States)

    Longru, Jin; He, Hong S.; Yufei, Zhou; Rencang, Bu; Keping, Sun

    2010-05-01

    Forest management often has cumulative, long-lasting effects on wildlife habitat suitability and the effects may be impractical to evaluate using landscape-scale field experiments. To understand such effects, we linked a spatially explicit landscape disturbance and succession model (LANDIS) with habitat suitability index (HSI) models to assess the effects of management alternatives on habitat suitability in a forested landscape of northeastern China. LANDIS was applied to simulate future forest landscape changes under four management alternatives (no cutting, clearcutting, selective cutting I and II) over a 200-year horizon. The simulation outputs were linked with HSI models for three wildlife species, the red squirrel ( Sciurus vulgaris), the red deer ( Cervus elaphus) and the hazel grouse ( Bonasa bonasia). These species are chosen because they represent numerous species that have distinct habitat requirements in our study area. We assessed their habitat suitability based on the mean HSI values, which is a measure of the average habitat quality. Our simulation results showed that no one management scenario was the best for all species and various forest management scenarios would lead to conflicting wildlife habitat outcomes. How to choose a scenario is dependent on the trade-off of economical, ecological and social goals. Our modeling effort could provide decision makers with relative comparisons among management scenarios from the perspective of biodiversity conservation. The general simulation results were expected based on our knowledge of forest management and habitat relationships of the species, which confirmed that the coupled modeling approach correctly simulated the assumed relationships between the wildlife, forest composition, age structure, and spatial configuration of habitat. However, several emergent results revealed the unexpected outcomes that a management scenario may lead to.

  15. [Effects of different forest management alternatives on Sciurus vulgaris habitat].

    Science.gov (United States)

    Jin, Long-Ru; He, Hong-Shi; Zong, Cheng; Zhou, Yu-Fei; Bu, Ren-Cang

    2008-05-01

    A spatially explicit landscape model LANDIS was applied to simulate the forest landscape changes under four management alternatives (no cutting, clear cutting, selective cutting I and II) in Youhao Forestry Bureau located in Small Xing' an Mountain from 2000 to 2200. The outcomes from LANDIS were combined with a landscape-level habitat suitability index (HSI) model in a GIS environment to assess Sciurus vulgaris habitat quality. The results showed that the increase of suitable habitat area and the decrease of marginally suitable area were the fastest under no cutting scenario, and the slowest under clear cutting scenario. Suitable habitat area increased faster while marginally suitable area decreased more slowly under selective cutting I scenario than under selective cutting II. Overall, the optimal management alternative of S. vulgaris habitat was in the sequence of no cutting, selective cutting I, selective cutting II, and clear cutting.

  16. Nitrogen Deposition Effects on Soil Carbon Dynamics in Temperate Forests

    DEFF Research Database (Denmark)

    Ginzburg Ozeri, Shimon

    incubated in litterbags had significantly lower late-stage decomposition rates compared with control litter. However, potential respiration of forest floor and mineral soil was overall unaffected by the experimental N-additions. A temperature treatment of forest floor samples taken from one edge site...... by needle litterfall were generally not significantly affected by N deposition at the edge sites but tended to increase with increasing distance from the edge in two of the N-saturated sites. The experimental N additions resulted in reduced C inputs by foliar litter relative to control concomitant...... reduced belowground C inputs under elevated N deposition. At two edge sites, forest floor C outputs by respiration tended to decrease with decreased forest floor C/N and distance from the edge indicating positive effect of elevated N deposition on SOC sequestration. Correspondingly, N-enriched litter...

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

    Science.gov (United States)

    Summerville, Keith S

    2011-04-01

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

  18. Simulation of the Effect of Intensive Forest Management on Forest Production in Sweden

    Directory of Open Access Journals (Sweden)

    Ola Rosvall

    2011-03-01

    Full Text Available The effects of intensifying the management of 15% of the Swedish forest land on potential future forest production over a 100-year period were investigated in a simulation study. The intensive management treatments, which were introduced over a period of 50 years, were: intensive fertilization of Norway spruce (IntFert; bulking-up Norway spruce elite populations using somatic embryogenesis (SE-seedlings; planting of lodgepole pine, hybrid larch, and Sitka spruce (Contorta, Larch, and Sitka; fertilization with wood ash on peatlands (Wood ash; and conventional fertilization in mature forests (ConFert. Potential sites for applying intensive forest management (IFM to sites with low nature conservation values were determined with a nature conservation score (NCS. Four different scenarios were simulated: “Base scenario”, which aimed at reducing the negative impact on nature conservation values, “Fast implementation”, “No IntFert” (IntFert was not used, and “Large Forest Companies”, where the majority of plots were selected on company land. Total yields during the 100-year simulation period were about 85–92% higher for the intensive forest management scenarios than for the reference scenario (business as usual. In the “No IntFert” scenario total production was 1.8% lower and in the “Large Forest Companies” scenario total production was 4.8% lower than in the “Base scenario”. “Fast implementation” of IFM increased yield by 15% compared to the “Base scenario”. Norway spruce SE-seedlings and IntFert gave the highest yields, measured as total production during the 100-year simulation period, but relative to the yields in the reference scenario, the highest increases in yield were for Contorta. The “Base scenario” and “No IntFert” gave the highest yields for plots with the lowest NCS, but plots with higher NCS had to be used in the “Fast implementation” and “Large Forest Companies” scenarios. More than

  19. Litter dynamics in two Sierran mixed conifer forests. II. Nutrient release in decomposing leaf litter

    Science.gov (United States)

    Stohlgren, Thomas J.

    1988-01-01

    The factors influencing leaf litter decomposition and nutrient release patterns were investigated for 3.6 years in two mixed conifer forests in the southern Sierra Nevada of California. The giant sequoia–fir forest was dominated by giant sequoia (Sequoiadendrongiganteum (Lindl.) Buchh.), white fir (Abiesconcolor Lindl. & Gord.), and sugar pine (Pinuslambertiana Dougl.). The fir–pine forest was dominated by white fir, sugar pine, and incense cedar (Calocedrusdecurrens (Torr.) Florin). Initial concentrations of nutrients and percent lignin, cellulose, and acid detergent fiber vary considerably in freshly abscised leaf litter of the studied species. Giant sequoia had the highest concentration of lignin (20.3%) and the lowest concentration of nitrogen (0.52%), while incense cedar had the lowest concentration of lignin (9.6%) and second lowest concentration of nitrogen (0.63%). Long-term (3.6 years) foliage decomposition rates were best correlated with initial lignin/N (r2 = 0.94, p r2 = 0.92, p r2 = 0.80, p < 0.05). Patterns of nutrient release were highly variable. Giant sequoia immobilized N and P, incense cedar immobilized N and to a lesser extent P, while sugar pine immobilized Ca. Strong linear or negative exponential relationships existed between initial concentrations of N, P, K, and Ca and percent original mass remaining of those nutrients after 3.6 years. This suggests efficient retention of these nutrients in the litter layer of these ecosystems. Nitrogen concentrations steadily increase in decomposing leaf litter, effectively reducing the C/N ratios from an initial range of 68–96 to 27–45 after 3.6 years.

  20. Effectiveness of management interventions on forest carbon stock in planted forests in Nepal.

    Science.gov (United States)

    Dangal, Shambhu Prasad; Das, Abhoy Kumar; Paudel, Shyam Krishna

    2017-07-01

    Nepal has successfully established more than 370,000 ha of plantations, mostly with Pinus patula, in the last three and a half decades. However, intensive management of these planted forests is very limited. Despite the fact that the Kyoto Convention in 1997 recognized the role of plantations for forest-carbon sequestration, there is still limited knowledge on the effects of management practices and stand density on carbon-sequestration of popular plantation species (i.e. Pinus patula) in Nepal. We carried out case studies in four community forests planted between 1976 and 1990 to assess the impacts of management on forest carbon stocks. The study found that the average carbon stock in the pine plantations was 217 Mg C ha -1 , and was lower in forests with intensively managed plantations (214.3 Mg C ha -1 ) than in traditionally managed plantations (219 Mg C ha -1 ). However, it was the reverse in case of soil carbon, which was higher (78.65 Mg C ha -1 ) in the forests with intensive management. Though stand density was positively correlated with carbon stock, the proportionate increment in carbon stock was lower with increasing stand density, as carbon stock increased by less than 25% with a doubling of stand density (300-600). The total carbon stock was higher in plantations aged between 25 and 30 years compared to those aged between 30 and 35 years. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Air Pollution and Forest Health: Establishing Cause and Effect in the Forest

    Directory of Open Access Journals (Sweden)

    William J. Manning

    2001-01-01

    Full Text Available I participated in a NATO Advanced Research Workshop titled “Effects of Air Pollution on Forest Health and Biodiversity in Forests of the Carpathian Mountains,” in Stara Lesna, Slovakia from May 22–26, 2001. Researchers from Canada, Czech Republic, Poland, Romania, Slovakia, Ukraine, and the U.S. met to present their results from a three-year cooperative study of tree health and air quality monitoring in forests of the Carpathian Mountains in Central Europe. Much of the work reported related to assessing the crown condition of trees in permanent plots in natural or managed (planted forests in the mountains. The endpoint was tree condition, with results extrapolated to the forests in the Carpathian range. From this I learned that, of the 50,000 trees evaluated, European beech (Fagus sylvatica was the most healthy, while Norway spruce (Picea abies (the principal forest tree and white fir (Abies alba sustained crown defoliation of up to 12.8%. The cause of this crown defoliation and tree decline was usually attributed to “air pollution” as a generic term and an automatic assumption. It is well known that deposition of heavy metals and acidic sulfur and nitrogen compounds can cause tree decline and predispose affected trees to bark beetles and climatic damage. Chemical analyses can also be done to detect metals and sulfur compounds in trees and soils. Sometimes these analyses were done, but most often the assumption was that crown defoliation was caused by air pollution. The assumption was that given sufficient exposure to high enough concentrations of toxic elements, sooner or later there will be a visible adverse response.

  2. Effects of Logged and Unlogged Forest Patches on Avifaunal Diversity

    Science.gov (United States)

    Ghadiri Khanaposhtani, Maryam; Kaboli, Mohammad; Karami, Mahmoud; Etemad, Vahid; Baniasadi, Saeedeh

    2013-03-01

    In the Hyrcanian forests of northern Iran, reduced-impact silviculture systems, (single-tree and group-tree selection) were applied over a large area, which generated different local habitat structures. The aim of this study was to assess the differences between treated and untreated areas of forest and their effect on avian richness, abundance and diversity (R.A.D). Birds were surveyed during the breeding season in 2009 by 100-point counts, equally distributed in the treated and untreated area. Avian R.A.D was significantly different and higher in the untreated area. Generally, forestry practices cause noticeable changes in canopy percentage, tree composition, snags and shrub number. Treated forest habitats in the area of study had a much more developed understory, fewer snags and fewer large diameter trees. The results highlighted the importance of forest maturity and showed that preventing silvicultural disturbances may not be the best solution for conserving and enhancing biodiversity. Rather, methods such as selective cutting seem an appropriate and sustainable way of forest management. It is suggested that forests should be managed to conserve structural elements which create favorable habitat for bird species, preventing future species losses due to logging practices.

  3. Effectiveness of China's National Forest Protection Program and nature reserves.

    Science.gov (United States)

    Ren, Guopeng; Young, Stephen S; Wang, Lin; Wang, Wei; Long, Yongcheng; Wu, Ruidong; Li, Junsheng; Zhu, Jianguo; Yu, Douglas W

    2015-10-01

    There is profound interest in knowing the degree to which China's institutions are capable of protecting its natural forests and biodiversity in the face of economic and political change. China's 2 most important forest-protection policies are its National Forest Protection Program (NFPP) and its national-level nature reserves (NNRs). The NFPP was implemented in 2000 in response to deforestation-caused flooding. We undertook the first national, quantitative assessment of the NFPP and NNRs to examine whether the NFPP achieved its deforestation-reduction target and whether the NNRs deter deforestation altogether. We used MODIS data to estimate forest cover and loss across mainland China (2000-2010). We also assembled the first-ever polygon dataset for China's forested NNRs (n = 237, 74,030 km(2) in 2000) and used both conventional and covariate-matching approaches to compare deforestation rates inside and outside NNRs (2000-2010). In 2000, 1.765 million km(2) or 18.7% of mainland China was forested (12.3% with canopy cover of ≥70%)) or woodland (6.4% with canopy cover forest and woodland had been lost, an annual deforestation rate of 2.7%. Forest-only loss was 127,473 km(2) (1.05% annually). In the NFPP provinces, the forest-only loss rate was 0.62%, which was 3.3 times lower than in the non-NFPP provinces. Moreover, the Landsat data suggest that these loss rates are overestimates due to large MODIS pixel size. Thus, China appears to have achieved, and even exceeded, its target of reducing deforestation to 1.1% annually in the NFPP provinces. About two-thirds of China's NNRs were effective in protecting forest cover (prevented loss 4073 km(2) unmatched approach; 3148 km(2) matched approach), and within-NNR deforestation rates were higher in provinces with higher overall deforestation. Our results indicate that China's existing institutions can protect domestic forest cover. © 2015 The Authors. Conservation Biology published by Wiley Periodicals, Inc., on behalf of

  4. Mixed Effectiveness of Africa's Tropical Protected Areas for Maintaining Forest Cover: Insights from a Global Forest Change Dataset

    Science.gov (United States)

    De Vos, A.; Bowker, J.; Ament, J.; Cumming, G.

    2016-12-01

    The effectiveness of parks for forest conservation is widely debated in Africa, where increasing human pressure, insufficient funding, and lack of management capacity frequently place significant demands on forest habitats. Tropical forests house a significant portion of the world's remaining biodiversity and are being heavily impacted by anthropogenic activity. We used Hansen et al.'s (2013) global forest change dataset to analyse park effectiveness at the individual (224 parks) and national (23 countries) level across Africa by comparing the extent of forest loss (as a proxy for deforestation) inside parks to matched unprotected control samples. We found that, although significant geographical variation exists between parks, the majority of African parks experienced significantly lower deforestation within their boundaries. Accessibility was a significant driver of deforestation, with less accessible areas having a higher probability of forest loss in ineffective parks and more accessible areas having a higher probability of forest loss in effective parks. Smaller parks were less effective at preventing forest loss inside park boundaries than larger parks, and older parks were less effective than younger parks. Our analysis, which is the first individual and national assessment of park effectiveness across Africa, demonstrates the complexity of factors influencing the ability of a park to curb deforestation within its boundaries and highlights the potential of web-based remote sensing technology in monitoring protected area effectiveness.

  5. Modeling and Validation across Scales: Parametrizing the effect of the forested landscape

    DEFF Research Database (Denmark)

    Dellwik, Ebba; Badger, Merete; Angelou, Nikolas

    be transferred into a parametrization of forests in wind models. The presentation covers three scales: the single tree, the forest edges and clearings, and the large-scale forested landscape in which the forest effects are parameterized with a roughness length. Flow modeling results and validation against...

  6. Effects of rural residential development on forest communities in Oregon and Washington, USA

    Science.gov (United States)

    David L. Azuma; Bianca N.I. Eskelson; Joel L. Thompson

    2014-01-01

    Rural residential development in forests of Oregon and Washington continues to be a key driver of land use change. This type of development can have a variety of effects on the goods and services forests provide to the region. We used structure density from photo-interpreted points around forest inventory and analysis plots to examine differences in forest attributes...

  7. Effects of satellite image spatial aggregation and resolution on estimates of forest land area

    Science.gov (United States)

    M.D. Nelson; R.E. McRoberts; G.R. Holden; M.E. Bauer

    2009-01-01

    Satellite imagery is being used increasingly in association with national forest inventories (NFIs) to produce maps and enhance estimates of forest attributes. We simulated several image spatial resolutions within sparsely and heavily forested study areas to assess resolution effects on estimates of forest land area, independent of other sensor characteristics. We...

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

    Science.gov (United States)

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

    2004-01-01

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

  9. Effect of triptolide on proliferation and apoptosis of angiotensin II ...

    African Journals Online (AJOL)

    Background: The effect of triptolide (TPL) on cardiac fibroblasts (CFbs) and cardiac fibrosis remain unknown till now. This study was conducted to explore the effects of TPL on proliferation and apoptosis of angiotensin II (Ang II)-induced CFbs. Materials and Methods: Ang II was used to promote proliferation of CFbs.

  10. View Angle Effects on MODIS Snow Mapping in Forests

    Science.gov (United States)

    Xin, Qinchuan; Woodcock, Curtis E.; Liu, Jicheng; Tan, Bin; Melloh, Rae A.; Davis, Robert E.

    2012-01-01

    Binary snow maps and fractional snow cover data are provided routinely from MODIS (Moderate Resolution Imaging Spectroradiometer). This paper investigates how the wide observation angles of MODIS influence the current snow mapping algorithm in forested areas. Theoretical modeling results indicate that large view zenith angles (VZA) can lead to underestimation of fractional snow cover (FSC) by reducing the amount of the ground surface that is viewable through forest canopies, and by increasing uncertainties during the gridding of MODIS data. At the end of the MODIS scan line, the total modeled error can be as much as 50% for FSC. Empirical analysis of MODIS/Terra snow products in four forest sites shows high fluctuation in FSC estimates on consecutive days. In addition, the normalized difference snow index (NDSI) values, which are the primary input to the MODIS snow mapping algorithms, decrease as VZA increases at the site level. At the pixel level, NDSI values have higher variances, and are correlated with the normalized difference vegetation index (NDVI) in snow covered forests. These findings are consistent with our modeled results, and imply that consideration of view angle effects could improve MODIS snow monitoring in forested areas.

  11. Levels I and II of the European Union in the forests of the state of Sachsen; Level I und II der Europaeischen Union (EU) in den saechsischen Waeldern

    Energy Technology Data Exchange (ETDEWEB)

    Raben, G.; Andreae, H.; Leube, F.; Symossek, F. [Saechsische Landesanstalt fuer Forsten (LAF), Pirna (Germany)

    2002-12-01

    Since 1993, a monitoring system accourding to the European Level I and Level II programms has been installed successively in the forests of the German state of Sachsen. Against the background of large-area acidification, sulphur levels were found to have decreased while nitrogen concentrations remain at high level and are often beyond the critical load. [German] Grundlage der Umweltkontrolle in den saechsischen Waeldern durch die LAF ist ein seit 1993 sukzessive nach den Methoden des europaeischen Level I bzw. II-Programms aufgebautes Monitoring-System. Die Ergebnisse der Untersuchungen zeigen u.a., dass vor dem Hintergrund grossflaechig versauerter Waldboeden die Stoffbelastungen durch Schwefelverbindungen stark zurueckgegangen sind, waehrend sie bezueglich der Stickstoffverbindungen anhaltend hoch sind. Diese Entwicklung spiegelt sich in den Ueberschreitungen der critical loads wider. (orig.)

  12. Illinois Natural Heritage Conservation/Education Kit II. Special Theme: Forest Ecology and Management.

    Science.gov (United States)

    Stone, Sally F.

    This instructional guide contains 16 activities designed to help teachers familiarize their students with the forest resources of Illinois. Each activity is ready to be copied and given to students. Topics of the activities, which vary in format, include: an overview of past and present Illinois forests; organization and mechanics of a forest…

  13. Forest and Water Management for Mitigating the effects of Climate ...

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

    Forest and Water Management for Mitigating the effects of Climate Change in the Middle Hills, Nepal. The Middle Hills in the Nepal Himalayas are home to a large part of the country's population. This area has been identified as particularly vulnerable to the impacts of climate change. Low rainfall and high temperatures in ...

  14. Effect of certain chemical attributes of vegetation on forest inflammability

    Science.gov (United States)

    Leon W. Richards

    1940-01-01

    Forest Service administrators and fire-research men have long felt the need of information concerning the effect of vegetation such as shrubs, grasses, and forbs (nongrasslike herbs) on the rate of spread of fires. To date, all knowledge of the subject has been acquired empirically in the field, or deduced from knowledge of fire behavior as influenced by the condition...

  15. Eutrophication of an Urban Forest Ecosystem: Causes and Effects

    Science.gov (United States)

    Bednova, O. V.; Kuznetsov, V. A.; Tarasova, N. P.

    2018-01-01

    The combined use of methods of passive dosimetry of the status of atmospheric air, phytoindication, and cartographic visualization of data made it possible to elaborate and substantiate approaches to evaluation of the effect of atmospheric air contamination on the eutrophication of forest ecosystems under urban conditions.

  16. Lineage-specific serology confirms Brazilian Atlantic forest lion tamarins, Leontopithecus chrysomelas and Leontopithecus rosalia, as reservoir hosts of Trypanosoma cruzi II (TcII).

    Science.gov (United States)

    Kerr, Charlotte L; Bhattacharyya, Tapan; Xavier, Samanta C C; Barros, Juliana H; Lima, Valdirene S; Jansen, Ana M; Miles, Michael A

    2016-11-15

    Trypanosoma cruzi, the agent of Chagas disease in humans, has a vast reservoir of mammalian hosts in the Americas, and is classified into six genetic lineages, TcI-TcVI, with a possible seventh, TcBat. Elucidating enzootic cycles of the different lineages is important for understanding the ecology of this parasite, the emergence of new outbreaks of Chagas disease and for guiding control strategies. Direct lineage identification by genotyping is hampered by limitations of parasite isolation and culture. An indirect method is to identify lineage-specific serological reactions in infected individuals; here we describe its application with sylvatic Brazilian primates. Synthetic peptides representing lineage-specific epitopes of the T. cruzi surface protein TSSA were used in ELISA with sera from Atlantic Forest Leontopithecus chrysomelas (golden-headed lion tamarin), L. rosalia (golden lion tamarin), Amazonian Sapajus libidinosus (black-striped capuchin) and Alouatta belzebul (red-handed howler monkey). The epitope common to lineages TcII, TcV and TcVI was recognised by sera from 15 of 26 L. chrysomelas and 8 of 13 L. rosalia. For 12 of these serologically identified TcII infections, the identity of the lineage infection was confirmed by genotyping T. cruzi isolates. Of the TcII/TcV/TcVI positive sera 12 of the 15 L. chrysomelas and 2 of the 8 L. rosalia also reacted with the specific epitope restricted to TcV and TcVI. Sera from one of six S. libidinous recognised the TcIV/TcIII epitopes. This lineage-specific serological surveillance has verified that Atlantic Forest primates are reservoir hosts of at least TcII, and probably TcV and TcVI, commonly associated with severe Chagas disease in the southern cone region of South America. With appropriate reagents, this novel methodology is readily applicable to a wide range of mammal species and reservoir host discovery.

  17. Soedra's ecological forest management plans. Effects on production and economy

    International Nuclear Information System (INIS)

    Viklund, E.

    1998-01-01

    In 1995 SOEDRA Skog, Sweden's largest forest owners association, started making ecological forest management plans, Groena skogsbruksplaner. The ecological forest management plans are divided into different compartments in which the management is adapted to the present ecological conditions. The stands are divided into four different categories depending on the different values of nature conservation. The object of this study was to find an easy method to quantify and describe the effects of nature conservation on economy and forest production in SOEDRA:s ecological forest management plans. The developed and purposed method, called PLAN-metoden, does not consider the interests, measures beyond the period of the plan, or losses due to snow or wind. It calculates the difference between the purposed measures in the ecological management plan and an alternative with management according to the requirements of the present Forestry Act. The economic effects of nature conservation varies between a net profit of 0,3% and a cost of 9,1% when calculated with the cash-flow method. The average decrease of possible cutting of merchantable timber was 11,3% and varies between 3,1 and 32,9%. The average decrease of cutting possibilities was 12,9% and varies between a decrease of 0,7% and a decrease of 28,3% when calculated with a present value method. Mainly mature, well-stocked compartments, which are considered not to be managed in the future, give rise to high costs. Properties with unprofitable thinnings and costly scarification, regeneration and cleaning seem to be favoured by the nature conservation in the plans. The Ecological management plans are expected to be of great importance to the members of SOEDRA. The interest in nature conservation is larger than that of economical issues. In order to avoid unsatisfactory results the planning should be accomplished in close personal contact with the forest owner Examination paper 1998-1. 21 refs, 2 figs, 39 tabs

  18. Effect of Group-Selection Opening Size on Breeding Bird Habitat Use in a Bottomland Forest

    Energy Technology Data Exchange (ETDEWEB)

    Moorman, C.E.; D.C. Guynn, Jr.

    2001-12-01

    Research on the effects of creating group-selection openings of various sizes on breeding birds habitat use in a bottomland hardwood forest of the Upper Coastal Plain of South Carolina. Creation of 0.5-ha group selection openings in southern bottomland forests should provide breeding habitat for some field-edge species in gaps and habitat for forest-interior species and canopy-dwelling forest-edge species between gaps provided that enough mature forest is made available.

  19. The effects of habitat edges and trampling intensity on vegetation in urban forests

    OpenAIRE

    Hamberg, Leena

    2009-01-01

    Although changes in urban forest vegetation have been documented in previous Finnish studies, the reasons for these changes have not been studied explicitly. Especially, the consequences of forest fragmentation, i.e. the fact that forest edges receive more solar radiation, wind and air-borne nutrients than interiors have been ignored. In order to limit the change in urban forest vegetation we need to know why it occurs. Therefore, the effects of edges and recreational use of urban forests on ...

  20. Acid deposition effects on forest composition and growth on the Monongahela National Forest, West Virginia

    Science.gov (United States)

    P.E. Elias; J.A. Burger; M.B. Adams

    2009-01-01

    The northern and central Appalachian forests are subject to high levels of atmospheric acid deposition (AD), which has been shown in some forests to negatively impact forest growth as well as predispose the forest system to damage from secondary stresses. The purpose of this study was to evaluate the possible contribution of AD to changes in composition and...

  1. Assessing the Effects of Forest Fragmentation Using Satellite Imagery and Forest Inventory Data

    Science.gov (United States)

    Ronald E. McRoberts; Greg C. Liknes

    2005-01-01

    For a study area in the North Central region of the USA, maps of predicted proportion forest area were created using Landsat Thematic Mapper imagery, forest inventory plot data, and a logistic regression model. The maps were used to estimate quantitative indices of forest fragmentation. Correlations between the values of the indices and forest attributes observed on...

  2. Long-term effects of different forest regeneration methods on mature forest birds

    Science.gov (United States)

    Roger W. Perry; Julianna M.A. Jenkins; Ronald E. Thill; Frank R. Thompson

    2018-01-01

    Changes in forest structure that result from silviculture, including timber harvest, can positively or negatively affect bird species that use forests. Because many bird species associated with mature forests are facing population declines, managers need to know how timber harvesting affects species of birds that rely on mature trees or forests for breeding, foraging,...

  3. Effects of climate and forest structure on palms, bromeliads and bamboos in Atlantic Forest fragments of Northeastern Brazil

    Directory of Open Access Journals (Sweden)

    R. R. Hilário

    Full Text Available Abstract Palms, bromeliads and bamboos are key elements of tropical forests and understanding the effects of climate, anthropogenic pressure and forest structure on these groups is crucial to forecast structural changes in tropical forests. Therefore, we investigated the effects of these factors on the abundance of these groups in 22 Atlantic forest fragments of Northeastern Brazil. Abundance of bromeliads and bamboos were assessed through indexes. Palms were counted within a radius of 20 m. We also obtained measures of vegetation structure, fragment size, annual precipitation, precipitation seasonality and human population density. We tested the effects of these predictors on plant groups using path analysis. Palm abundance was higher in taller forests with larger trees, closed canopy and sparse understory, which may be a result of the presence of seed dispersers and specific attributes of local palm species. Bromeliads were negatively affected by both annual precipitation and precipitation seasonality, what may reflect adaptations of these plants to use water efficiently, but also the need to capture water in a regular basis. Bamboos were not related to any predictor variable. As climate and forest structure affected the abundance of bromeliads and palms, human-induced climatic changes and disturbances in forest structure may modify the abundance of these groups. In addition, soil properties and direct measurements of human disturbance should be used in future studies in order to improve the predictability of models about plant groups in Northeastern Atlantic Forest.

  4. Effects of forest die-off on hydrologic processes in southern Appalachian forests

    Science.gov (United States)

    Vose, J.; Ford, C. R.

    2011-12-01

    Forests in the southern Appalachian region of the eastern U.S. have been impacted by numerous disturbances over the past century. Many of these disturbances have resulted in non-random species losses. For example, in the early 1900s, American chestnut (Castenea dentata) was decimated by the chestnut blight. Severe droughts in the 1980s and 1990s resulted in significant southern pine beetle (Dendroctonus frontalis, SPB) outbreaks; and, most of the native pines (Pinus rigida) were killed. These same droughts resulted in a pulse of mortality of older red oaks and extensive SPB infestation of white pine (Pinus strobus) plantations. In the 2000s, the introduction of the hemlock woolly adelgid (HWA) resulted in widespread mortality of eastern hemlock (Tsuga canadensis). Linking hydrologic responses to partial or complete changes in forest conditions due to die-off is especially challenging in the eastern U.S. because high vegetation diversity and substantial differences in tree-level water use makes it difficult to generalize or predict responses. Gauged watersheds and sapflow monitoring across multiple tree species at the Coweeta Hydrologic Laboratory in western NC provides a unique opportunity to quantify the impacts of large-scale forest die-off on hydrologic processes. Here, we provide three examples of our efforts to quantify and predict impacts. First, we analyzed long-term streamflow data from WS17, a 53 year old white pine plantation, where approximately 15% of the watershed was killed by SPB in the late 1990s. Second, we examined the effects of losing an individual species (i.e., loss of eastern hemlock from HWA) using sapflow, long-term permanent plot data, and models to scale from the individual tree to the watershed. Third, sapflow data from 11 forest canopy species were used to evaluate the potential impacts of losses of individual species on stand transpiration. Annual streamflow responses are exponentially related to decreases in forest cover (e.g., from

  5. The Thermal Proximity Effect: A New Probe of the He II Reionization History and Quasar Lifetime

    Science.gov (United States)

    Khrykin, I. S.; Hennawi, J. F.; McQuinn, M.

    2017-04-01

    Despite decades of effort, the timing and duration of He II reionization and the properties of the quasars believed to drive it are still not well constrained. We present a new method to study both via the thermal proximity effect—the heating of the intergalactic medium (IGM) around quasars when their radiation doubly ionizes helium. We post-process hydrodynamical simulations with 1D radiative transfer and study how the thermal proximity effect depends on the He II fraction, {x}{He{{II}},0}, which prevailed in the IGM before the quasar turned on, and the quasar lifetime {t}{{Q}}. We find that the amplitude of the temperature boost in the quasar environment depends on {x}{He{{II}},0}, with a characteristic value of {{Δ }}T≃ {10}4 {{K}} for {x}{He{{II}},0}=1.0, whereas the size of the thermal proximity zone is sensitive to {t}{{Q}}, with typical sizes of ≃ 100 {cMpc} for {t}{{Q}}={10}8 {yr}. This temperature boost increases the thermal broadening of H I absorption lines near the quasar. We introduce a new Bayesian statistical method based on measuring the Lyα forest power spectrum as a function of distance from the quasar, and demonstrate that the thermal proximity effect should be easily detectable. For a mock data set of 50 quasars at z≃ 4, we predict that one can measure {x}{He{{II}},0} to an (absolute) precision ≈ 0.04 and {t}{{Q}} to a precision of ≈ 0.1 dex. By applying our formalism to existing high-resolution Lyα forest spectra, one should be able to reconstruct the He II reionization history, providing a global census of hard photons in the high-z universe.

  6. Fertilizing Douglas-fir forests.

    Science.gov (United States)

    Richard E. Miller; Roger D. Right

    1979-01-01

    This report supplements a slide-tape presentation of the same title. Part I of the report describes the current practice of nitrogen fertilization of Douglas-fir forests in western Washington and Oregon and the effects of this fertilization on tree growth and water quality. Part II discusses factors that affect costs and revenues from investments in forest...

  7. Structuring Effects of Deer in Boreal Forest Ecosystems

    Directory of Open Access Journals (Sweden)

    Steeve D. Côté

    2014-01-01

    Full Text Available Many deer populations have recently increased worldwide leading to strong direct and indirect ecological and socioeconomical impacts on the composition, dynamic, and functions of forest ecosystems. Deer directly modify the composition and structure of vegetation communities, but they also indirectly affect other species of the ecosystem by modifying the structure of the vegetation. Here we review the results of a research program on overabundant white-tailed deer (Odocoileus virginianus in the boreal forest of Anticosti Island (Québec, Canada aimed at identifying deer densities compatible with forest regeneration. Various silvicultural systems and treatments failed to regenerate deer habitat at high deer densities, but planting size-adapted seedlings could be effective at moderate densities. Using a controlled deer density experiment, we found vegetation recovery at deer densities ≤ 15 deer/km2. The same experiment revealed that other groups of organisms such as insects and birds responded favorably to a reduction of deer density. We also found that alternative successional trajectories may occur after a certain period of heavy browsing during early succession. We conclude that one of the most important remaining research gaps is the need to identify habitat-specific threshold densities at which deer impacts occur and then to design effective wildlife and forest management strategies to limit deer impacts and sustain ecosystem integrity.

  8. Positive effects of radiation on forest production

    International Nuclear Information System (INIS)

    Gonzalez J, J.; De la Cruz O, A.; Aguilar, M. A.; Caxnajoy, P. A.; Salceda S, V.

    2009-10-01

    The deforestation is a world problem and due to of increment of seed demand and seedling of good quality, was realized a work about the production improvement on commercial or forest trees for the Mexico State. It was combined the use of two techniques: the plant tissue culture and ionizing application. It was utilized seed of Pinus hartwegii collected and valued previously by ProBosque, with them were formed homogeneous lots that were irradiated to dose of 0, 30, 45, 60, 75, 90 and 105 Gy into irradiator Gammacel-220 and later were decontaminated and cultivated in vitro. The seeds-planting were placed in a growth room with temperature and controlled light. After 10 cultivation days was obtained germination among 87-100% without observing the induction of negative changes in none of treatments. After 21 days already developed the embryos completely, modifications were presented in some structures. With these was possible to determine the lethal dose mean that oscillates between 100 and 105 Gy; since to dose bigger than 100 Gy more of 75% of individuals or seedlings present the phenols formation inducing the material lost by oxidation starting from day 32. Also, it is observed that applied doses between the 30 and 90 Gy do not affect or modify the embryogenesis in Pinus hartwegii but if the structures formation and seedling size since after 12 development days it is possible to appreciate to dose of 90, 75 and 45 Gy the presence of a primary radicular system, same that is observed after 22 development days in the witness. Another observation was that to dose of 45 and 90 Gy the leafs presents bigger elongation increasing the seedlings size on 22% in comparison with the witness. We can say that the doses understood between 45 and 90 Gy affect in a positive way the hormonal production of Pinus hartwegii seedlings and that the dose of 90 Gy accelerates the rhizogenes process and it increases the seedling size allowing to diminish the production time of Pinus hartwegii

  9. ISLSCP II Carbon Dioxide Flux at Harvard Forest and Northern BOREAS Sites

    Data.gov (United States)

    National Aeronautics and Space Administration — Carbon dioxide flux and meteorological data for the Harvard Forest, MA (1992-95) and BOREAS Northern Study Area, Old Black Spruce (Alberta, Canada; 1994-95) FLUXNET...

  10. ISLSCP II Carbon Dioxide Flux at Harvard Forest and Northern BOREAS Sites

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: Carbon dioxide flux and meteorological data for the Harvard Forest, MA (1992-95) and BOREAS Northern Study Area, Old Black Spruce (Alberta, Canada;...

  11. Roads as edges: Effects on birds in forested landscapes

    Science.gov (United States)

    Yvette K. Ortega; David E. Capen

    2002-01-01

    Numerous studies have documented that forest edges affect habitat use and reproductive success of forest birds, but few studies have considered edges created by narrow breaks in the forest canopy. We compared predation rates on artificial nests placed within forest habitat along edge transects, 10 m from unpaved roads, and along interior transects, 300 m from forest-...

  12. [Effects of different type urban forest plantations on soil fertility].

    Science.gov (United States)

    Sun, Hui-zhen; Chen, Ming-yue; Cai, Chun-ju; Zhu, Ning

    2009-12-01

    Aimed to study the effects of different urban forest plantations on soil fertility, soil samples were collected from eight mono-cultured plantations (Larix gmelinii, Pinus sylvestris var. mongolica, Pinus tabulaeformis var. mukdensis, Phellodendron amurense, Juglans mandshurica, Fraxinus mandshurica, Betula platyphylla, and Quercus mongolica) and one mixed plantation (P. sylvestris var. mongolica + F. mandshurica + Picea koraiensis + P. amurense + B. platyphylla) established in Northeast Forestry University's Urban Forestry Demonstration Research Base in the 1950s, with two sites of neighboring farmland and abandoned farmland as the control. The soils in broadleaved forest plantations except Q. mongolica were near neutral, those in mixed plantation, L. gmelinii, P. sylvestris var. mongolica, and P. tabulaeformis var. mukdensis were slightly acidic, and that in Q. mongolica was acidic. The contents of soil organic matter, total N and P, available P and K, and hydrolysable N tended to decrease with soil depth. There existed significant differences in the chemical indices of the same soil layers among different plantations. The soil fertility was decreased in the order of F. mandshurica > P. amurense > mixed plantation > J. mandshurica > B. platyphylla > abandoned farmland > farmland > P. sylvestris var. mongolica > L. gmelinii > Q. mongolica > P. tabulaeformis var. mukdensis, suggesting that the soil fertility in broadleaved forest plantations except Q. mongolica and in mixed plantation increased, while that in needle-leaved forest plantations tended to decrease.

  13. Climate and Vegetation Effects on Temperate Mountain Forest ...

    Science.gov (United States)

    Current forest composition may be resilient to typical climatic variability; however, climate trends, combined with projected changes in species composition, may increase tree vulnerability to water stress. A shift in forest composition toward tree species with higher water use has implications for biogenic emissions and deposition of reactive nitrogen and carbon compounds. Forest evapotranspiration (ET) can vary greatly at daily and seasonal time scales, but compared to carbon fluxes, often exhibits relatively consistent inter-annual behavior. The processes controlling ET involve the combined effects of physical and biological factors. Atmospheric conditions that promote high ET, consisting of high radiation and vapor pressure deficit (D), are often characterized by rainless periods when soil water supply to vegetation may be limiting and plant stomata may close to prevent excessive water loss. In contrast, periods of high ecosystem water availability require frequent precipitation and are characterized by low D. Thus, the combination of these contrasting conditions throughout a growing season may explain some of the consistency in ET. Additionally, vegetation composition is also an important factor in determining ET. In mixed species forests, physiological differences in water use strategies (e.g. isohydric/anisohydric species) can produce conservative water use throughout wet and dry phases of the growing season. Furthermore, transpiration by evergreen specie

  14. Modelling forest carbon stock changes as affected by harvest and natural disturbances. II. EU-level analysis

    Directory of Open Access Journals (Sweden)

    Roberto Pilli

    2016-08-01

    Full Text Available Abstract Background Forests and the forest sector may play an important role in mitigating climate change. The Paris Agreement and the recent legislative proposal to include the land use sector in the EU 2030 climate targets reflect this expectation. However, greater confidence on estimates from national greenhouse gas inventories (GHGI and more comprehensive analyses of mitigation options are needed to seize this mitigation potential. The aim of this paper is to provide a tool at EU level for verifying the EU GHGI and for simulating specific policy and forest management scenarios. Therefore, the Carbon Budget Model (CBM was applied for an integrated assessment of the EU forest carbon (C balance from 2000 to 2012, including: (i estimates of the C stock and net CO2 emissions for forest management (FM, afforestation/reforestation (AR and deforestation (D, covering carbon in both the forest and the harvest wood product (HWP pools; (ii an overall analysis of the C dynamics associated with harvest and natural disturbances (mainly storms and fires; (iii a comparison of our estimates with the data reported in the EU GHGI. Results Overall, the average annual FM sink (−365 Mt CO2 year−1 estimated by the CBM in the period 2000–2012 corresponds to about 7 % of total GHG emissions at the EU level for the same period (excluding land use, land-use change and forestry. The HWP pool sink (−44 Mt CO2 year−1 contributes an additional 1 %. Emissions from D (about 33 Mt CO2 year−1 are more than compensated by the sink in AR (about 43 Mt CO2 year−1 over the period. For FM, the estimates from the CBM were about 8 % lower than the EU GHGI, a value well within the typical uncertainty range of the EU forest sink estimates. For AR and D the match with the EU GHGI was nearly perfect (difference <±2 % in the period 2008–2012. Our analysis on harvest and natural disturbances shows that: (i the impact of harvest is much greater than natural disturbances

  15. Nitrogen Deposition Effects on Soil Carbon Dynamics in Temperate Forests

    DEFF Research Database (Denmark)

    Ginzburg Ozeri, Shimon

    edges were used to study the effects of varying N deposition load on SOC stocks and fluxes as well as on the temperature sensitivity of SOM respiration. In a third study, the effects of 20 years of continuous experimental N addition (35 kg N ha-1 year-1) on soil C budget were investigated. Our general...... incubated in litterbags had significantly lower late-stage decomposition rates compared with control litter. However, potential respiration of forest floor and mineral soil was overall unaffected by the experimental N-additions. A temperature treatment of forest floor samples taken from one edge site......Soils contain the largest fraction of terrestrial carbon (C). Understanding the factors regulating the decomposition and storage of soil organic matter (SOM) is essential for predictions of the C sink strength of the terrestrial environment in the light of global change. Elevated long-term nitrogen...

  16. Effect of multi-temporal forest cover change trajectories on forest plant diversity

    Science.gov (United States)

    One of the principal tenets of landscape ecology is that forest loss and fragmentation negatively affects biodiversity. However, historical fluctuations in forest cover resulting from repeated cycles of deforestation and reforestation are likely important in influencing patterns ...

  17. International co-operative program on assessment and monitoring of air pollution effects on forests: The Sierra Ancha Experimental Forest, Arizona

    Science.gov (United States)

    Boris Poff; Daniel G. Neary

    2008-01-01

    At the end of the 2007 Fiscal Year, the Experimental Forests and Ranges (EFR) Synthesis Network Committee awarded funds to 18 sites to establish a strategic ICP Level II (described below) synthesis network in the United States. Eleven Experimental Forest were selected to be included in the network, as well as seven Long Term Ecological Research (LTER) sites. This will...

  18. Do forest gap model simulations of climate change effects have a catastrophist bias?

    Energy Technology Data Exchange (ETDEWEB)

    LeBlanc, D.C. [Ball State Univ., Muncie, IN (United States). Dept. of Biology; Loehle, C. [Argonne National Lab., IL (United States)

    1997-08-01

    Forest gap simulation models have been widely used to project potential effects of global climate change on forest ecosystems. These projections are given high visibility in governmental and intergovernmental reports that are part of the basis for formulating national and international policy regarding global change. The most recent draft report from the IPCC is but one of many cases where the results from forest gap simulation models have been used as the best available projection of the effects of climate change on forests.

  19. Cumulative Effects of Barriers on the Movements of Forest Birds

    Directory of Open Access Journals (Sweden)

    Marc Bélisle

    2002-01-01

    Full Text Available Although there is a consensus of opinion that habitat fragmentation has deleterious effects on animal populations, primarily by inhibiting dispersal among remaining patches, there have been few explicit demonstrations of the ways by which degraded habitats actually constrain individual movement. Two impediments are primarily responsible for this paucity: it is difficult to separate the effects of habitat fragmentation (configuration from habitat loss (composition, and conventional measures of fragmented habitats are assumed to be, but probably are not, isotropic. We addressed these limitations by standardizing differences in forest cover in a clearly anisotropic configuration of habitat fragmentation by conducting a homing experiment with three species of forest birds in the Bow Valley of Banff National Park, Canada. Birds were translocated (1.2-3.5  km either parallel or perpendicular to four/five parallel barriers that are assumed to impede the cross-valley travel of forest-dependent animals. Taken together, individuals exhibited longer return times when they were translocated across these barriers, but differences among species suggest a more complex interpretation. A long-distance migrant (Yellow-rumped Warbler, Dendroica coronata behaved as predicted, but a short-distance migrant (Golden-crowned Kinglet, Regulus satrapa was indifferent to barrier configuration. A resident (Red-breasted Nuthatch, Sitta canadensis exhibited longer return times when it was translocated parallel to the barriers. Our results suggest that an anisotropic arrangement of small, open areas in fragmented landscapes can have a cumulative barrier effect on the movement of forest animals, but that both modelers and managers will have to acknowledge potentially counterintuitive differences among species to predict the effect that these may have on individual movement and, ultimately, dispersal.

  20. The effect of serum angiotensin II and angiotensin II type 1 receptor ...

    African Journals Online (AJOL)

    Ehab

    2012-06-18

    Jun 18, 2012 ... The effect of serum angiotensin II and angiotensin II type 1 receptor gene polymorphism on pediatric lupus nephritis. INTRODUCTION. Renin angiotensin system (RAS) has been considered one of the probable pathophysiologic mechanisms involved in SLE progression. However, the contribution of the ...

  1. Soil Effects on Forest Structure and Diversity in a Moist and a Dry Tropical Forest

    NARCIS (Netherlands)

    Peña-Claros, M.; Poorter, L.; Alarcon, A.; Blate, G.; Choque, U.; Fredericksen, T.S.; Justiniano, J.; Leaño, C.; Licona, J.C.; Pariona, W.; Putz, F.E.; Quevedo, L.; Toledo, M.

    2012-01-01

    Soil characteristics are important drivers of variation in wet tropical forest structure and diversity, but few studies have evaluated these relationships in drier forest types. Using tree and soil data from 48 and 32 1 ha plots, respectively, in a Bolivian moist and dry forest, we asked how soil

  2. [Effect of forest management on the herpetofauna of a temperate forest of western Oaxaca, Mexico].

    Science.gov (United States)

    Aldape-López, César Tonatiuh; Santos-Moreno, Antonio

    2016-09-01

    The development of silvicultural techniques has as main objective to maximize the production of timber, whereas at the same time minimize the impact generated during and after forest intervention in the local diversity. However, these activities change local climate, and this, in turn, alter the composition of natural communities. The effect of these changes may be greater in those taxonomic groups with high sensitivity to habitat disturbance, such as amphibians and reptiles, which are the unique terrestrial ectothermic vertebrates. The present study aims to know the differences in diversity of amphibians and reptiles in a temperate forest under two silvicultural treatments, one of low and the other of high intensity, as well as from one, five and ten years of regeneration since the last logging event, Sierra Sur of Oaxaca, Mexico. Records of 21 species of herpetofauna (six amphibians and 15 reptiles) were obtained. The total species richness was similar in both treatments; however, the composition varied between sites with different recovery times. Higher abundance of amphibian was presented on sites with the low-intensity treatment, while reptiles were more abundant at sites with intensive treatment. Compared to a mature forest without management, sites with intensive treatment have more rare species, although the values of true diversity of amphibians were similar between treatments with different intensities, while for reptiles sites under treatment showed less diversity that unmanaged site: 33 % for intensive treatment and 28 % at sites with low intensity with respect to one control site. Complementary Analysis showed a difference of 86 % between the compositions of species in sites with intensive treatment. The treatment intensity was associated with an increase in the number of species, but the way they respond to changes in habitat depends largely on the population characteristics of each species and its ability to adapt to new conditions.

  3. Lineage-specific serology confirms Brazilian Atlantic forest lion tamarins, Leontopithecus chrysomelas and Leontopithecus rosalia, as reservoir hosts of Trypanosoma cruzi II (TcII

    Directory of Open Access Journals (Sweden)

    Charlotte L. Kerr

    2016-11-01

    Full Text Available Abstract Background Trypanosoma cruzi, the agent of Chagas disease in humans, has a vast reservoir of mammalian hosts in the Americas, and is classified into six genetic lineages, TcI-TcVI, with a possible seventh, TcBat. Elucidating enzootic cycles of the different lineages is important for understanding the ecology of this parasite, the emergence of new outbreaks of Chagas disease and for guiding control strategies. Direct lineage identification by genotyping is hampered by limitations of parasite isolation and culture. An indirect method is to identify lineage-specific serological reactions in infected individuals; here we describe its application with sylvatic Brazilian primates. Methods Synthetic peptides representing lineage-specific epitopes of the T. cruzi surface protein TSSA were used in ELISA with sera from Atlantic Forest Leontopithecus chrysomelas (golden-headed lion tamarin, L. rosalia (golden lion tamarin, Amazonian Sapajus libidinosus (black-striped capuchin and Alouatta belzebul (red-handed howler monkey. Results The epitope common to lineages TcII, TcV and TcVI was recognised by sera from 15 of 26 L. chrysomelas and 8 of 13 L. rosalia. For 12 of these serologically identified TcII infections, the identity of the lineage infection was confirmed by genotyping T. cruzi isolates. Of the TcII/TcV/TcVI positive sera 12 of the 15 L. chrysomelas and 2 of the 8 L. rosalia also reacted with the specific epitope restricted to TcV and TcVI. Sera from one of six S. libidinous recognised the TcIV/TcIII epitopes. Conclusions This lineage-specific serological surveillance has verified that Atlantic Forest primates are reservoir hosts of at least TcII, and probably TcV and TcVI, commonly associated with severe Chagas disease in the southern cone region of South America. With appropriate reagents, this novel methodology is readily applicable to a wide range of mammal species and reservoir host discovery.

  4. Effectiveness of community forest management at reducing deforestation in Madagascar

    DEFF Research Database (Denmark)

    Rasolofoson, Ranaivo Andriarilala; Ferraro, Paul J.; Jenkins, Clinton N.

    2015-01-01

    Community Forest Management (CFM) is a widespread conservation approach in the tropics. It is also promoted as a means by which payment for ecosystem services schemes can be implemented. However, evidence on its performance is weak. We investigated the effectiveness of CFM at reducing deforestation...... restricted the sample to only where information suggests effective CFM implementation on the ground. Likewise, we cannot detect an effect of CFM where commercial use of natural resources is allowed. However, we can detect a reduction in deforestation in CFM that does not permit commercial uses, compared...

  5. Environmental effects of ash application in forest ecosystems

    DEFF Research Database (Denmark)

    Hansen, Mette

    of ashes being produced and the export of nutrients from the forests. This PhD project aims at investigating how ash application in forest ecosystems affects soil and soil solution properties and whether ash application can be used in a Danish context without environmental harm but with positive effects...... rate, ash application can have negative impact on the soil capacity to store C. This PhD study shows that ash application can be used in a Danish context without environmental harm. To ensure the practice to be more widespread than it is today, measures can be made to improve the Danish legislation...... defining the rules for ash application. Based on my findings, I suggest that the dose of ash applied is increased to 6 Mg ha-1 instead of 3 Mg ha-1, while at the same time reducing the initial Cd concentration in the ash and/or prohibiting the use of fly ashes alone....

  6. Breeding Guild Determines Frog Distributions in Response to Edge Effects and Habitat Conversion in the Brazil's Atlantic Forest.

    Directory of Open Access Journals (Sweden)

    Rodrigo B Ferreira

    Full Text Available Understanding the response of species with differing life-history traits to habitat edges and habitat conversion helps predict their likelihood of persistence across changing landscape. In Brazil's Atlantic Forest, we evaluated frog richness and abundance by breeding guild at four distances from the edge of a reserve: i 200 m inside the forest, ii 50 m inside the forest, iii at the forest edge, and iv 50 m inside three different converted habitats (coffee plantation, non-native Eucalyptus plantation, and abandoned pastures, hereafter matrix types. By sampling a dry and a wet season, we recorded 622 individual frogs representing 29 species, of which three were undescribed. Breeding guild (i.e. bromeliad, leaf-litter, and water-body breeders was the most important variable explaining frog distributions in relation to edge effects and matrix types. Leaf-litter and bromeliad breeders decreased in richness and abundance from the forest interior toward the matrix habitats. Water-body breeders increased in richness toward the matrix and remained relatively stable in abundance across distances. Number of large trees (i.e. DBH > 15 cm and bromeliads best explained frog richness and abundance across distances. Twenty species found in the interior of the forest were not found in any matrix habitat. Richness and abundance across breeding guilds were higher in the rainy season but frog distributions were similar across the four distances in the two seasons. Across matrix types, leaf-litter species primarily used Eucalyptus plantations, whereas water-body species primarily used coffee plantations. Bromeliad breeders were not found inside any matrix habitat. Our study highlights the importance of primary forest for bromeliad and leaf-litter breeders. We propose that water-body breeders use edge and matrix habitats to reach breeding habitats along the valleys. Including life-history characteristics, such as breeding guild, can improve predictions of frog

  7. Breeding Guild Determines Frog Distributions in Response to Edge Effects and Habitat Conversion in the Brazil's Atlantic Forest.

    Science.gov (United States)

    Ferreira, Rodrigo B; Beard, Karen H; Crump, Martha L

    2016-01-01

    Understanding the response of species with differing life-history traits to habitat edges and habitat conversion helps predict their likelihood of persistence across changing landscape. In Brazil's Atlantic Forest, we evaluated frog richness and abundance by breeding guild at four distances from the edge of a reserve: i) 200 m inside the forest, ii) 50 m inside the forest, iii) at the forest edge, and iv) 50 m inside three different converted habitats (coffee plantation, non-native Eucalyptus plantation, and abandoned pastures, hereafter matrix types). By sampling a dry and a wet season, we recorded 622 individual frogs representing 29 species, of which three were undescribed. Breeding guild (i.e. bromeliad, leaf-litter, and water-body breeders) was the most important variable explaining frog distributions in relation to edge effects and matrix types. Leaf-litter and bromeliad breeders decreased in richness and abundance from the forest interior toward the matrix habitats. Water-body breeders increased in richness toward the matrix and remained relatively stable in abundance across distances. Number of large trees (i.e. DBH > 15 cm) and bromeliads best explained frog richness and abundance across distances. Twenty species found in the interior of the forest were not found in any matrix habitat. Richness and abundance across breeding guilds were higher in the rainy season but frog distributions were similar across the four distances in the two seasons. Across matrix types, leaf-litter species primarily used Eucalyptus plantations, whereas water-body species primarily used coffee plantations. Bromeliad breeders were not found inside any matrix habitat. Our study highlights the importance of primary forest for bromeliad and leaf-litter breeders. We propose that water-body breeders use edge and matrix habitats to reach breeding habitats along the valleys. Including life-history characteristics, such as breeding guild, can improve predictions of frog distributions in

  8. Effects of climate variability and accelerated forest thinning on watershed-scale runoff in southwestern USA ponderosa pine forests.

    Science.gov (United States)

    Robles, Marcos D; Marshall, Robert M; O'Donnell, Frances; Smith, Edward B; Haney, Jeanmarie A; Gori, David F

    2014-01-01

    The recent mortality of up to 20% of forests and woodlands in the southwestern United States, along with declining stream flows and projected future water shortages, heightens the need to understand how management practices can enhance forest resilience and functioning under unprecedented scales of drought and wildfire. To address this challenge, a combination of mechanical thinning and fire treatments are planned for 238,000 hectares (588,000 acres) of ponderosa pine (Pinus ponderosa) forests across central Arizona, USA. Mechanical thinning can increase runoff at fine scales, as well as reduce fire risk and tree water stress during drought, but the effects of this practice have not been studied at scales commensurate with recent forest disturbances or under a highly variable climate. Modifying a historical runoff model, we constructed scenarios to estimate increases in runoff from thinning ponderosa pine at the landscape and watershed scales based on driving variables: pace, extent and intensity of forest treatments and variability in winter precipitation. We found that runoff on thinned forests was about 20% greater than unthinned forests, regardless of whether treatments occurred in a drought or pluvial period. The magnitude of this increase is similar to observed declines in snowpack for the region, suggesting that accelerated thinning may lessen runoff losses due to warming effects. Gains in runoff were temporary (six years after treatment) and modest when compared to mean annual runoff from the study watersheds (0-3%). Nonetheless gains observed during drought periods could play a role in augmenting river flows on a seasonal basis, improving conditions for water-dependent natural resources, as well as benefit water supplies for downstream communities. Results of this study and others suggest that accelerated forest thinning at large scales could improve the water balance and resilience of forests and sustain the ecosystem services they provide.

  9. Effects of Climate Variability and Accelerated Forest Thinning on Watershed-Scale Runoff in Southwestern USA Ponderosa Pine Forests

    Science.gov (United States)

    Robles, Marcos D.; Marshall, Robert M.; O'Donnell, Frances; Smith, Edward B.; Haney, Jeanmarie A.; Gori, David F.

    2014-01-01

    The recent mortality of up to 20% of forests and woodlands in the southwestern United States, along with declining stream flows and projected future water shortages, heightens the need to understand how management practices can enhance forest resilience and functioning under unprecedented scales of drought and wildfire. To address this challenge, a combination of mechanical thinning and fire treatments are planned for 238,000 hectares (588,000 acres) of ponderosa pine (Pinus ponderosa) forests across central Arizona, USA. Mechanical thinning can increase runoff at fine scales, as well as reduce fire risk and tree water stress during drought, but the effects of this practice have not been studied at scales commensurate with recent forest disturbances or under a highly variable climate. Modifying a historical runoff model, we constructed scenarios to estimate increases in runoff from thinning ponderosa pine at the landscape and watershed scales based on driving variables: pace, extent and intensity of forest treatments and variability in winter precipitation. We found that runoff on thinned forests was about 20% greater than unthinned forests, regardless of whether treatments occurred in a drought or pluvial period. The magnitude of this increase is similar to observed declines in snowpack for the region, suggesting that accelerated thinning may lessen runoff losses due to warming effects. Gains in runoff were temporary (six years after treatment) and modest when compared to mean annual runoff from the study watersheds (0–3%). Nonetheless gains observed during drought periods could play a role in augmenting river flows on a seasonal basis, improving conditions for water-dependent natural resources, as well as benefit water supplies for downstream communities. Results of this study and others suggest that accelerated forest thinning at large scales could improve the water balance and resilience of forests and sustain the ecosystem services they provide. PMID

  10. [Effects of artificial Ulmus pumila forest on plant diversity of temperate grassland in Inner Mongolia].

    Science.gov (United States)

    Yang, Hong-Xiao; Wang, Xue-Quan; Yang, Wen-Bin; Lu, Qi

    2008-06-01

    Based on field survey, the effects of artificial Ulmus pumila forest on the species diversity of temperate grassland in Siziwang Banner of Inner Mongolia were studied. The results showed that U. pumila forest had obvious effects on the species diversity of grassland. With increasing density of U. pumila, the Patrick's richness, Pielou's evenness and Shannon-Wiener index of grass species under the forest had a decreasing trend, and were higher nearby the forest than far from the forest. The habitat inside the forest was favorable to Silene jenisseensis, while that nearby the forest was favorable to Heteropappus altaicus, Pocockia ruthenia, Potentilla bifurca, Leymus secalinus and Cleistogenes squarrosa, suggesting that to blindly exclude forestation on grassland could be less scientific, while properly afforesting U. pumila on the sides with relatively abundant soil moisture should be available to the conservation of plant diversity in temperate grassland regions.

  11. Effects of forest cover on drinking water treatment costs

    Science.gov (United States)

    Travis Warziniack; Chi Ho Sham; Robert Morgan; Yasha Feferholtz

    2016-01-01

    This paper explores the relationship between forest cover and drinking water treatment costs using results from a 2014 survey by the American Water Works Association (AWWA) that targeted utilities in forested ecoregions in the United States. On the basis of the data collected, there is a negative relationship between forest cover and turbidity, i.e. as forest...

  12. Effects of harvesting on spatial and temporal diversity of carbon stocks in a boreal forest landscape.

    Science.gov (United States)

    Ter-Mikaelian, Michael T; Colombo, Stephen J; Chen, Jiaxin

    2013-10-01

    Carbon stocks in managed forests of Ontario, Canada, and in harvested wood products originated from these forests were estimated for 2010-2100. Simulations included four future forest harvesting scenarios based on historical harvesting levels (low, average, high, and maximum available) and a no-harvest scenario. In four harvesting scenarios, forest carbon stocks in Ontario's managed forest were estimated to range from 6202 to 6227 Mt C (millions of tons of carbon) in 2010, and from 6121 to 6428 Mt C by 2100. Inclusion of carbon stored in harvested wood products in use and in landfills changed the projected range in 2100 to 6710-6742 Mt C. For the no-harvest scenario, forest carbon stocks were projected to change from 6246 Mt C in 2010 to 6680 Mt C in 2100. Spatial variation in projected forest carbon stocks was strongly related to changes in forest age (r = 0.603), but had weak correlation with harvesting rates. For all managed forests in Ontario combined, projected carbon stocks in combined forest and harvested wood products converged to within 2% difference by 2100. The results suggest that harvesting in the boreal forest, if applied within limits of sustainable forest management, will eventually have a relatively small effect on long-term combined forest and wood products carbon stocks. However, there was a large time lag to approach carbon equality, with more than 90 years with a net reduction in stored carbon in harvested forests plus wood products compared to nonharvested boreal forest which also has low rates of natural disturbance. The eventual near equivalency of carbon stocks in nonharvested forest and forest that is harvested and protected from natural disturbance reflects both the accumulation of carbon in harvested wood products and the relatively young age at which boreal forest stands undergo natural succession in the absence of disturbance.

  13. The effects of forest fires on the stand history of New Jersey's pine region

    Science.gov (United States)

    S. Little

    1946-01-01

    This paper summarizes the present knowledge on the effects of forest fires in the Pine Region of New Jersey. It is not the result of any one research project, but the combined result of research and observations. Its purpose is to acquaint foresters and others having some knowledge of forestry and conservation with the importance of forest fires and the part they have...

  14. Hydrologic effects of a changing forested landscape--challenges for the hydrological sciences

    Science.gov (United States)

    J.A. Jones; G.L. Achterman; L.A. Augustine; I.F. Creed; P.F. Ffolliott; L. MacDonald; B.C. Wemple

    2009-01-01

    Of all the ecological services of forests, a sustainable water supply may be the most important. Streamflow from forests provides two-thirds of fresh water supply in the United States. Removing forest cover temporarily increases the proportion of precipitation that becomes streamflow, and this effect has spurred political pressure to cut trees for the purpose of...

  15. Air pollution and climate change effects on health of the Ukrainian forests: monitoring and evalution

    Science.gov (United States)

    Igor F. Buksha; Valentina L. Meshkova; Oleg M. Radchenko; Alexander S. Sidorov

    1998-01-01

    Forests in the Ukraine are affected by environmental pollution, intensive forestry practice, and recreational uses. These factors make them sensitive to impacts of climate change. Since 1989 Ukraine has participated in the International Cooperative Program on Assessment and Monitoring of Air Pollution Effects on Forests (ICP-Forests). A network of monitoring plots has...

  16. Effects of roads on elk: implications for management in forested ecosystems.

    Science.gov (United States)

    Mary M. Rowland; Michael J. Wisdom; Bruce K. Johnson; Mark A. Penninger

    2004-01-01

    The effects of roads on both habitat and population responses of elk (Cervus elaphus) have been of keen interest to foresters and ungulate biologists for the last half century. Increased timber harvest in national forests, beginning in the 1960s, led to a proliferation of road networks in forested ecosystems inhabited by elk (Hieb 1976, Lyon and...

  17. Effects of air pollution and simulated acid rain on the ground vegetation of coniferous forests

    International Nuclear Information System (INIS)

    Rodenkirchen, H.

    1993-01-01

    Descriptive and experimental studies on the ground vegetation of coniferous forests in Bavaria indicated the following phenomena: a. In N-limited pine forests recent eutrophication effects occur. b. The structure of the moss layer in coniferous forests sensitively reacts to very acid throughfall water (pH [de

  18. Effects of forest fragmentation and habitat degradation on West African leaf-litter frogs

    NARCIS (Netherlands)

    Hillers, A.; Veith, M.; Rödel, M.-O.

    2008-01-01

    Habitat degradation alters the dynamics and composition of anuran assemblages in tropical forests. The effects of forest fragmentation on the composition of anuran assemblages are so far poorly known. We studied the joint influence of forest fragmentation and degradation on leaf-litter frogs. We

  19. Effects of needleleaf forest cover on radiation and snowmelt dynamics in the Canadian Rocky Mountains

    OpenAIRE

    Ellis, C. R.; Pomeroy, J. W.; Essery, R. L. H.; Link, T. E.

    2011-01-01

    Radiation is the main energy source for snowpack warming and melt in mountain needleleaf forests, and runoff from these forests is the main contributor to spring river flows in western North America. Utilizing extensive field observations, the effect of needleleaf forest cover on radiation and snowmelt timing was quantified at pine and spruce forest sites and nearby clearings of varying slope and aspect in an eastern Canadian Rocky Mountain headwater basin. Compared with open clearing sites, ...

  20. Increasing soil temperature in a northern hardwood forest: effects on elemental dynamics and primary productivity

    Science.gov (United States)

    Patrick J. McHale; Myron J. Mitchell; Dudley J. Raynal; Francis P. Bowles

    1996-01-01

    To investigate the effects of elevated soil temperatures on a forest ecosystem, heating cables were buried at a depth of 5 cm within the forest floor of a northern hardwood forest at the Huntington Wildlife Forest (Adirondack Mountains, New York). Temperature was elevated 2.5, 5.0 and 7.5?C above ambient, during May - September in both 1993 and 1994. Various aspects of...

  1. The effects of forest structure on occurrence and abundance of three owl species (Aves: Strigidae in the Central Amazon forest

    Directory of Open Access Journals (Sweden)

    Obed G. Barros

    2009-03-01

    Full Text Available We investigated how forest structure affects the occurrence and abundance of three owl species: the crested owl Lophostrix cristata Daudin, 1800, the Amazon pygmy owl Glaucidium hardyi Vielliard, 1990, and the tawny-bellied screech owl Megascops watsonii Cassin, 1849. We surveyed the owls mostly between 07:00 and 11:00 pm from July 2001 to April 2002, in eighteen 8 km transects along trails at the Ducke Reserve, Manaus, Central Amazon, Brazil. We staked out 50 x 50 m plots where the presence and absence of the owls were recorded. We compared some components of the forest structure between plots where owls were present and plots where they were absent. The spatial variation in these components were related to the occurrence and abundance of the owls using models of multiple logistic and multiple linear regressions analysis, respectively. Lophostrix cristata is rare in many other areas of the Amazon forest, but it was the most abundant in our study area. Lophostrix cristata and G. hardyi were more concentrated along the uplands (central plateau, which divide the reserve into two drainage water-basins. Megascops watsonii was distributed mainly in the southeastern part of the reserve. Glaucidium hardyi was more often found in areas with larger canopy openness. In areas with higher abundance of snags, there was significantly higher occurrence of L. cristata and M. watsonii. Megascops watsonii was also more abundant in areas with higher abundance of forest trees and in areas bearing shallower leaf litter on the forest floor. This study is the first to analyze at large spatial scale the effects of forest structure on neotropical forest top predator nocturnal birds. The results indicate that forest structure can affect the occurrence and abundance of owls in the Amazon forest.

  2. Physiological Effects of Visual Stimulation with Forest Imagery

    Directory of Open Access Journals (Sweden)

    Chorong Song

    2018-01-01

    Full Text Available This study was aimed to clarify the physiological effects of visual stimulation using forest imagery on activity of the brain and autonomic nervous system. Seventeen female university students (mean age, 21.1 ± 1.0 years participated in the study. As an indicator of brain activity, oxyhemoglobin (oxy-Hb concentrations were measured in the left and right prefrontal cortex using near-infrared time-resolved spectroscopy. Heart rate variability (HRV was used as an indicator of autonomic nervous activity. The high-frequency (HF component of HRV, which reflected parasympathetic nervous activity, and the ratio of low-frequency (LF and high-frequency components (LF/HF, which reflected sympathetic nervous activity, were measured. Forest and city (control images were used as visual stimuli using a large plasma display window. After sitting at rest viewing a gray background for 60 s, participants viewed two images for 90 s. During rest and visual stimulation, HRV and oxy-Hb concentration in the prefrontal cortex were continuously measured. Immediately thereafter, subjective evaluation of feelings was performed using a modified semantic differential (SD method. The results showed that visual stimulation with forest imagery induced (1 a significant decrease in oxy-Hb concentrations in the right prefrontal cortex and (2 a significant increase in perceptions of feeling “comfortable,” “relaxed,” and “natural.”

  3. Mutagenic effects of lead (II) bromide.

    Science.gov (United States)

    Maslat, A O; Haas, H J

    1989-12-01

    The mutagenicity of lead (II) bromide (a combustion product of the gasoline additives lead (IV) tetraethyl and 1,2-dibromoethane) was investigated using various strains of bacteria. Taking prodigiosin (the red pigment) production as a marker, lead (II) bromide was found to be mutagenic in S. marcescens, leading to the appearance of white mutant colonies that are unable to produce such a pigment. This compound was also found to be mutagenic in E. coli KMBL1851, resulting in the appearance of rifampicin-resistant mutants in addition to Met+ and His+ revertants. Some of the S. marcescens mutants were found to be reversible, able to resynthesize prodigiosin. Differences in the sensitivity to antibiotics as well as in the biochemical properties were detected between the mutants and their corresponding wild types. Lead (II) bromide gave positive results in the Ames test performed with strain TA 1535.

  4. Increasing the effectiveness of native forest regeneration and reforestation: towards climate-change adaptation in drylands

    Science.gov (United States)

    Branquinho, Cristina; Príncipe, Adriana; Nunes, Alice; Kobel, Melanie; Soares, Cristina; Pinho, Pedro

    2016-04-01

    The recent expansion of the semiarid climate to all the region of the south of Portugal and the growing impact of climate change demands local adaptation. The growth of the native forest represents a strategy at the ecosystem level to adapt to climate change since it increases resilience and increases also de delivery of ecosystem services such as the increment of organic matter in the soil, carbon and nitrogen, biodiversity, water infiltration, etc. Moreover decreases susceptibility to desertification. For that reason, large areas have been reforested in the south of Portugal with the native species holm oak and cork oak but with a low rate of effectiveness. Our goal in this work is to show how the cost-benefit relation of the actions intended to expand the forest of the Portuguese semiarid can be lowered by taking into account the microclimatic conditions and high spatial resolution management. The potential of forest regeneration was modelled at the local and regional level in the semiarid area using information concerning the Potential Solar Radiation. This model gives us the rate of native forest regeneration after a disturbance with high spatial resolution. Based on this model the territory was classified in: i) easy regeneration areas; ii) areas with the need of assisted reforestation, using methods that increase water and soil conservation; iii) areas of difficult reforestation because of the costs. Additionally a summary of the success of reforestations was made in the historical semiarid since the 60s based on the evaluation of a series of case studies, where we quantified the ecosystem services currently delivered by the reforested ecosystems. Acknowledgement: Programa Adapt: financed by EEA Grants and Fundo Português de Carbono

  5. [Chronology of tropical dry forest regeneration in Santa Rosa, Guanacaste, Costa Rica. II. Vegetation in relation to the soil].

    Science.gov (United States)

    Leiva, Jorge A; Rocha, Oscar J; Mata, Rafael; Gutiérrez-Soto, Marco V

    2009-09-01

    Tropical dry forest (TDF) succession was monitored in Santa Rosa, Costa Rica. We analyzed the effect of soil type on forest structure and diversity. Eight seasonally-dry TDF sites located along a successional chrono-sequence (10, 15, 20, 40, 60 and >100 years) were examined in relation to 17 soil pedons and six soil orders. Soils had moderate to high fertility and were classified as Entisols and Vertisols, although Mollisols, Alfisols, Inceptisols and Ultisols were also present. One-hundred and thirty 500 m2 plots were established, 20 plots in secondary and 10 plots in mature TDF sites. Diameter at breast height (dbh) and total tree height were measured for saplings (dbh > or = 1 and or = 5 cm). With the exception of two sites (40 and 60 years), soil type did not have significant effects on forest structure. However, tree diversity measured with Shannon-Wiener's H' and Fisher's alpha rarefaction curves, showed substantial differences among soil types, which became accentuated in mature forests. This pattern might be explained by non-random distributions of TDF trees, the scale of the study, the plot shape, and the use of systematic sampling designs. Low-fertility sites in general had higher species richness, consistent with idea that more restrictive soils reduce competition among trees and allow co-existence of species with contrasting growth rates. Changes in soil properties along a chrono-sequence of Entisols indicated that trees may experience more severe water stress as succession progresses, which may require adjustments in biomass allocation and phenological behavior of the dominant species. Our results suggest that edaphic specialization is more pronounced in mature TDF forests, and that most TDF trees are generalists in relation to soil type, highly tolerant to site heterogeneity, and show little physiological specializations in response to edaphic heterogeneity.

  6. Effects of reforestation practices on Staphylinid beetles (Coleoptera: Staphylinidae) in Southwestern China forests.

    Science.gov (United States)

    Luo, Tian-Hong; Yu, Xiao-Dong; Zhou, Hong-Zhang

    2013-02-01

    In 2004, Staphylinid beetle (Coleoptera) assemblages were studied via pitfall trapping to examine the effects of reforestation in southwestern China forests. Sites included two 100-yr-old mature forest types (hemlock-spruce forest and birch forest), and three 40-yr-old forest types established after harvesting (spruce plantation, larch plantation, and natural broad-leaved forest). Staphylinid species richness was greater in natural broad-leaved forests than those in hemlock-spruce forests and spruce plantations, but no significant difference was found in abundance among the five forest types. Beetle assemblages from young forest stands were significantly different from those in older forest stands, and some environmental characteristics, i.e., elevation, proportion of broad-leaved trees, and coarse woody debris, significantly affected species abundances. Moreover, some staphylinid species predominantly found only in older forest stands indicate that mature forest specialists might be threatened by loss of habitat. So it is necessary to retain adequate patches of older successional stages for conserving these beetle assemblages.

  7. Effects of dust on forest tree health in Zagros oak forests.

    Science.gov (United States)

    Moradi, A; Taheri Abkenar, K; Afshar Mohammadian, M; Shabanian, N

    2017-10-10

    Dust is one of the most devastating factors for the environment threatening all animal and plant species. In many regions, the ecological and economic impact of microdust on scarce species is critical. In the western region of Iran, the Zagros forests have been exposed to dust storms for many years. In this study, the effect of dust on oak trees, the most important trees of Zagros forests, is investigated. For this purpose, 3-year-old seedlings of three species of oak trees under natural conditions were exposed to dust during spring and summer months. Seedlings were divided into two groups; one group was assigned as dust treatment and the other as control that the control group washed regularly to remove dust. Anatomical characteristics of leaves and dust deposits on leaves during the study period were examined by scanning electron microscope (SEM). The rate of photosynthesis and gas exchange in control and treated plants was examined by IRGA, LCI. SEM images showed that stomata structure, trichome density, and epicuticular waxes of leaves are different in all three species. This difference in micromorphology of species influences the effects of dust deposited on the leaves. A comparison of leaf species images in control and dust treatment showed that in dust treatment the percentage of stomata blocked by dust in three species (per unit area) of Quercus infectoria, Q. libni, and Q. brantii were 61/6, 48/4, and 38/1%, respectively. The results of leaf gas exchange investigation indicated that stomatal occlusion by dust had a negative impact on the examined parameters of three oak species (P ≤ 0.01). Thus, gas exchange and photosynthetic rates of the treated species were significantly reduced. The results of both parts of the study showed the vulnerability of the three species to dust as Q. infectoria > Q. libni > Q. brantii. Therefore, based on these findings, dust can disrupt the physiological activities of the studied species and the continuation of the

  8. Forest report 2016

    International Nuclear Information System (INIS)

    2016-01-01

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

  9. Edge effect on palm diversity in rain forest fragments in western Ecuador

    DEFF Research Database (Denmark)

    Baez, S.; Balslev, Henrik

    2007-01-01

      At the edges of tropical rain forest fragments, altered abiotic and biotic conditions influence the structure and dynamics of plant communities. In Neotropical rain forests, palms (Arecaceae) are important floristic and ecological elements. Palms' responses to edge effects appear...... effects influence the relative proportion of palm adults and juveniles, (2) how distance from the forest edge affects palm density and species richness, (3) how altered forest structure along edges affects palm density. We found that at edges (1) palm communities had a lower proportion of adults relative...... to juvenile individuals compared to continuous forests, (2) the density of two species of palms and the overall species richness of the palm community tended to decrease toward the edges within forest fragments, and, (3) altered forest structure decreased the density of adult palms. Hence, edge effects...

  10. Riparian forest buffers mitigate the effects of deforestation on fish assemblages in tropical headwater streams.

    Science.gov (United States)

    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

  11. Dominant effect of increasing forest biomass on evapotranspiration: interpretations of movement in Budyko space

    Directory of Open Access Journals (Sweden)

    F. Jaramillo

    2018-01-01

    Full Text Available During the last 6 decades, forest biomass has increased in Sweden mainly due to forest management, with a possible increasing effect on evapotranspiration. However, increasing global CO2 concentrations may also trigger physiological water-saving responses in broadleaf tree species, and to a lesser degree in some needleleaf conifer species, inducing an opposite effect. Additionally, changes in other forest attributes may also affect evapotranspiration. In this study, we aimed to detect the dominating effect(s of forest change on evapotranspiration by studying changes in the ratio of actual evapotranspiration to precipitation, known as the evaporative ratio, during the period 1961–2012. We first used the Budyko framework of water and energy availability at the basin scale to study the hydroclimatic movements in Budyko space of 65 temperate and boreal basins during this period. We found that movements in Budyko space could not be explained by climatic changes in precipitation and potential evapotranspiration in 60 % of these basins, suggesting the existence of other dominant drivers of hydroclimatic change. In both the temperate and boreal basin groups studied, a negative climatic effect on the evaporative ratio was counteracted by a positive residual effect. The positive residual effect occurred along with increasing standing forest biomass in the temperate and boreal basin groups, increasing forest cover in the temperate basin group and no apparent changes in forest species composition in any group. From the three forest attributes, standing forest biomass was the one that could explain most of the variance of the residual effect in both basin groups. These results further suggest that the water-saving response to increasing CO2 in these forests is either negligible or overridden by the opposite effect of the increasing forest biomass. Thus, we conclude that increasing standing forest biomass is the dominant driver of long-term and large

  12. Dominant effect of increasing forest biomass on evapotranspiration: interpretations of movement in Budyko space

    Science.gov (United States)

    Jaramillo, Fernando; Cory, Neil; Arheimer, Berit; Laudon, Hjalmar; van der Velde, Ype; Hasper, Thomas B.; Teutschbein, Claudia; Uddling, Johan

    2018-01-01

    During the last 6 decades, forest biomass has increased in Sweden mainly due to forest management, with a possible increasing effect on evapotranspiration. However, increasing global CO2 concentrations may also trigger physiological water-saving responses in broadleaf tree species, and to a lesser degree in some needleleaf conifer species, inducing an opposite effect. Additionally, changes in other forest attributes may also affect evapotranspiration. In this study, we aimed to detect the dominating effect(s) of forest change on evapotranspiration by studying changes in the ratio of actual evapotranspiration to precipitation, known as the evaporative ratio, during the period 1961-2012. We first used the Budyko framework of water and energy availability at the basin scale to study the hydroclimatic movements in Budyko space of 65 temperate and boreal basins during this period. We found that movements in Budyko space could not be explained by climatic changes in precipitation and potential evapotranspiration in 60 % of these basins, suggesting the existence of other dominant drivers of hydroclimatic change. In both the temperate and boreal basin groups studied, a negative climatic effect on the evaporative ratio was counteracted by a positive residual effect. The positive residual effect occurred along with increasing standing forest biomass in the temperate and boreal basin groups, increasing forest cover in the temperate basin group and no apparent changes in forest species composition in any group. From the three forest attributes, standing forest biomass was the one that could explain most of the variance of the residual effect in both basin groups. These results further suggest that the water-saving response to increasing CO2 in these forests is either negligible or overridden by the opposite effect of the increasing forest biomass. Thus, we conclude that increasing standing forest biomass is the dominant driver of long-term and large-scale evapotranspiration

  13. The effect of increasing salinity and forest mortality on soil nitrogen and phosphorus mineralization in tidal freshwater forested wetlands

    Science.gov (United States)

    Noe, Gregory B.; Krauss, Ken W.; Lockaby, B. Graeme; Conner, William H.; Hupp, Cliff R.

    2013-01-01

    Tidal freshwater wetlands are sensitive to sea level rise and increased salinity, although little information is known about the impact of salinification on nutrient biogeochemistry in tidal freshwater forested wetlands. We quantified soil nitrogen (N) and phosphorus (P) mineralization using seasonal in situ incubations of modified resin cores along spatial gradients of chronic salinification (from continuously freshwater tidal forest to salt impacted tidal forest to oligohaline marsh) and in hummocks and hollows of the continuously freshwater tidal forest along the blackwater Waccamaw River and alluvial Savannah River. Salinification increased rates of net N and P mineralization fluxes and turnover in tidal freshwater forested wetland soils, most likely through tree stress and senescence (for N) and conversion to oligohaline marsh (for P). Stimulation of N and P mineralization by chronic salinification was apparently unrelated to inputs of sulfate (for N and P) or direct effects of increased soil conductivity (for N). In addition, the tidal wetland soils of the alluvial river mineralized more P relative to N than the blackwater river. Finally, hummocks had much greater nitrification fluxes than hollows at the continuously freshwater tidal forested wetland sites. These findings add to knowledge of the responses of tidal freshwater ecosystems to sea level rise and salinification that is necessary to predict the consequences of state changes in coastal ecosystem structure and function due to global change, including potential impacts on estuarine eutrophication.

  14. Clustering Timber Harvests and the Effects of Dynamic Forest Management Policy on Forest Fragmentation

    Science.gov (United States)

    Eric J. Gustafson

    1998-01-01

    To integrate multiple uses (mature forest and commodity production) better on forested lands, timber management strategies that cluster harvests have been proposed. One such approach clusters harvest activity in space and time, and rotates timber production zones across the landscape with a long temporal period (dynamic zoning). Dynamic zoning has...

  15. Edge effects at an induced forest-grassland boundary: forest birds in ...

    African Journals Online (AJOL)

    Bird species diversity and guild composition between the edge (5-10 m from the margin) of primary forest abutting grassland and the deep interior (> 500 m from the margin) in the Dngoye Forest Reserve were compared. Edge and interior sites were chosen that were homogeneous with respect to habitat physiognomy i.e. ...

  16. Effects of forest roads on habitat quality for Ovenbirds in a forested landscape

    Science.gov (United States)

    Yvette K. Ortega; David E. Capen

    1999-01-01

    Numerous studies have reported lower densities of breeding Ovenbirds (Seiurus aurocapillus) adjacent to forest edges. However, none of these studies has considered habitat use and reproductive success to address mechanisms underlying the observed pattern, and most were conducted in fragmented landscapes and ignored juxtapositions of forest with...

  17. Effective kinematic viscosity of turbulent He II

    Czech Academy of Sciences Publication Activity Database

    Chagovets, Tymofiy; Gordeev, A. V.; Skrbek, L.

    2007-01-01

    Roč. 76, č. 2 (2007), 027301/1-027301/4 ISSN 1539-3755 R&D Projects: GA ČR GA202/05/0218 Institutional research plan: CEZ:AV0Z10100520 Keywords : ĺiquid helium II * decaying counetrflow turbulence * mutual friction * grid turbulence * rotating helium * finite channel * heat current Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.483, year: 2007

  18. Health Effect of Forest Bathing Trip on Elderly Patients with Chronic Obstructive Pulmonary Disease.

    Science.gov (United States)

    Jia, Bing Bing; Yang, Zhou Xin; Mao, Gen Xiang; Lyu, Yuan Dong; Wen, Xiao Lin; Xu, Wei Hong; Lyu, Xiao Ling; Cao, Yong Bao; Wang, Guo Fu

    2016-03-01

    Forest bathing trip is a short, leisurely visit to forest. In this study we determined the health effects of forest bathing trip on elderly patients with chronic obstructive pulmonary disease (COPD). The patients were randomly divided into two groups. One group was sent to forest, and the other was sent to an urban area as control. Flow cytometry, ELISA, and profile of mood states (POMS) evaluation were performed. In the forest group, we found a significant decrease of perforin and granzyme B expressions, accompanied by decreased levels of pro-inflammatory cytokines and stress hormones. Meanwhile, the scores in the negative subscales of POMS decreased after forest bathing trip. These results indicate that forest bathing trip has health effect on elderly COPD patients by reducing inflammation and stress level. Copyright © 2016 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

  19. [Effects of climate change on forest soil organic carbon storage: a review].

    Science.gov (United States)

    Zhou, Xiao-yu; Zhang, Cheng-yi; Guo, Guang-fen

    2010-07-01

    Forest soil organic carbon is an important component of global carbon cycle, and the changes of its accumulation and decomposition directly affect terrestrial ecosystem carbon storage and global carbon balance. Climate change would affect the photosynthesis of forest vegetation and the decomposition and transformation of forest soil organic carbon, and further, affect the storage and dynamics of organic carbon in forest soils. Temperature, precipitation, atmospheric CO2 concentration, and other climatic factors all have important influences on the forest soil organic carbon storage. Understanding the effects of climate change on this storage is helpful to the scientific management of forest carbon sink, and to the feasible options for climate change mitigation. This paper summarized the research progress about the distribution of organic carbon storage in forest soils, and the effects of elevated temperature, precipitation change, and elevated atmospheric CO2 concentration on this storage, with the further research subjects discussed.

  20. Local cooling and warming effects of forests based on satellite observations

    OpenAIRE

    Li, Yan; Zhao, Maosheng; Motesharrei, Safa; Mu, Qiaozhen; Kalnay, Eugenia; Li, Shuangcheng

    2015-01-01

    The biophysical effects of forests on climate have been extensively studied with climate models. However, models cannot accurately reproduce local climate effects due to their coarse spatial resolution and uncertainties, and field observations are valuable but often insufficient due to their limited coverage. Here we present new evidence acquired from global satellite data to analyse the biophysical effects of forests on local climate. Results show that tropical forests have a strong cooling ...

  1. Edge effects enhance carbon uptake and its vulnerability to climate change in temperate broadleaf forests.

    Science.gov (United States)

    Reinmann, Andrew B; Hutyra, Lucy R

    2017-01-03

    Forest fragmentation is a ubiquitous, ongoing global phenomenon with profound impacts on the growing conditions of the world's remaining forest. The temperate broadleaf forest makes a large contribution to the global terrestrial carbon sink but is also the most heavily fragmented forest biome in the world. We use field measurements and geospatial analyses to characterize carbon dynamics in temperate broadleaf forest fragments. We show that forest growth and biomass increase by 89 ± 17% and 64 ± 12%, respectively, from the forest interior to edge, but ecosystem edge enhancements are not currently captured by models or approaches to quantifying regional C balance. To the extent that the findings from our research represent the forest of southern New England in the United States, we provide a preliminary estimate that edge growth enhancement could increase estimates of the region's carbon uptake and storage by 13 ± 3% and 10 ± 1%, respectively. However, we also find that forest growth near the edge declines three times faster than that in the interior in response to heat stress during the growing season. Using climate projections, we show that future heat stress could reduce the forest edge growth enhancement by one-third by the end of the century. These findings contrast studies of edge effects in the world's other major forest biomes and indicate that the strength of the temperate broadleaf forest carbon sink and its capacity to mitigate anthropogenic carbon emissions may be stronger, but also more sensitive to climate change than previous estimates suggest.

  2. Climate and Vegetation Effects on Temperate Mountain Forest Evapotranspiration

    Science.gov (United States)

    Current forest composition may be resilient to typical climatic variability; however, climate trends, combined with projected changes in species composition, may increase tree vulnerability to water stress. A shift in forest composition toward tree species with higher water use h...

  3. Assessing the effect of climate change on carbon sequestration in a Mexican dry forest in the Yucatan Peninsula

    Science.gov (United States)

    Z. Dai; K.D. Johnson; R.A. Birdsey; J.L. Hernandez-Stefanoni; J.M. Dupuy

    2015-01-01

    Assessing the effect of climate change on carbon sequestration in tropical forest ecosystems is important to inform monitoring, reporting, and verification (MRV) for reducing deforestation and forest degradation (REDD), and to effectively assess forest management options under climate change. Two process-based models, Forest-DNDC and Biome-BGC, with different spatial...

  4. NED-IIS: An Intelligent Information System for Forest Ecosystem Management

    Science.gov (United States)

    W.D. Potter; S. Somasekar; R. Kommineni; H.M. Rauscher

    1999-01-01

    We view Intelligent Information System (IIS) as composed of a unified knowledge base, database, and model base. The model base includes decision support models, forecasting models, and cvsualization models for example. In addition, we feel that the model base should include domain specific porblems solving modules as well as decision support models. This, then,...

  5. Behavioral effects of urotensin-II centrally administered in mice.

    Science.gov (United States)

    Do-Rego, Jean-Claude; Chatenet, David; Orta, Marie-Hélène; Naudin, Bertrand; Le Cudennec, Camille; Leprince, Jérôme; Scalbert, Elizabeth; Vaudry, Hubert; Costentin, Jean

    2005-11-01

    Urotensin-II (U-II) receptors are widely distributed in the central nervous system. Intracerebroventricular (i.c.v.) injection of U-II causes hypertension and bradycardia and stimulates prolactin and thyrotropin secretion. However, the behavioral effects of centrally administered U-II have received little attention. In the present study, we tested the effects of i.c.v. injections of U-II on behavioral, metabolic, and endocrine responses in mice. Administration of graded doses of U-II (1-10,000 ng/mouse) provoked: (1) a dose-dependent reduction in the number of head dips in the hole-board test; (2) a dose-dependent reduction in the number of entries in the white chamber in the black-and-white compartment test, and in the number of entries in the central platform and open arms in the plus-maze test; and (3) a dose-dependent increase in the duration of immobility in the forced-swimming test and tail suspension test. Intracerebroventricular injection of U-II also caused an increase in: food intake at doses of 100 and 1,000 ng/mouse, water intake at doses of 100-10,000 ng/mouse, and horizontal locomotion activity at a dose of 10,000 ng/mouse. Whatever was the dose, the central administration of U-II had no effect on body temperature, nociception, apomorphine-induced penile erection and climbing behavior, and stress-induced plasma corticosterone level. Taken together, the present study demonstrates that the central injection of U-II at doses of 1-10,000 ng/mouse induces anxiogenic- and depressant-like effects in mouse. These data suggest that U-II may be involved in some aspects of psychiatric disorders.

  6. Effects of habitat fragmentation on bird communities of sand forests ...

    African Journals Online (AJOL)

    We investigated the influence of forest fragment size and isolation on the bird assemblages in the species- and endemic-rich sand forests of the Maputaland Centre of Endemism, southern Mozambique. Point-centre surveys were conducted across 12 sand forest patches that varied in size and isolation. Patch size and ...

  7. Effective radium concentration in agricultural versus forest topsoils

    International Nuclear Information System (INIS)

    Perrier, Frédéric; Girault, Frédéric; Bouquerel, Hélène; Bollinger, Laurent

    2016-01-01

    Effective radium-226 activity concentration (EC Ra ), the radon-222 source term, was measured in the laboratory with 724 topsoil samples collected over a ∼110 km 2 area located ∼20 km south of Paris, France. More than 2100 radon accumulation experiments were performed, with radon concentration measured using scintillation flasks, leading to relative uncertainties on EC Ra varying from 10% for EC Ra  = 2 Bq⋅kg −1 to less than 6% for EC Ra  > 5 Bq⋅kg −1 . Small-scale dispersion, studied at one location with 12 samples, and systematically at 100 locations with three topsoils separated by 1 m, was of the order of 7%, demonstrating that a single soil sample is reasonably representative. Agricultural topsoils (n = 540) had an average (arithmetic) EC Ra of 8.09 ± 0.11 Bq⋅kg −1 , and a range from 2.80 ± 0.22 to 19.5 ± 1.1 Bq⋅kg −1 , while forest topsoils (n = 184), with an average of 3.21 ± 0.14 Bq⋅kg −1 and a range from 0.45 ± 0.12 to 9.09 ± 0.55 Bq⋅kg −1 , showed a clear systematic reduction of EC Ra when compared with the closest agricultural soil sample. Large-scale organization of EC Ra was impressive for agricultural topsoils, with homogeneous domains of several kilometers size, characterized by smooth variations smaller than 10%. These patches emerged despite heavy human remodeling; they are controlled by the main geographical units, but do not necessarily coincide with them. Valleys were characterized by larger dispersion and less organization. This study illustrates how biosphere and anthroposphere modify the soil distribution inherited from geological processes, an important baseline needed for the study of contaminated sites. Furthermore, the observed depletion of forest topsoils suggests an atmospheric radon signature of deforestation. - Highlights: • Effective radium concentration EC Ra measured with >720 topsoils over 110 km 2 region. • EC Ra of agricultural and forest topsoils homogeneous at

  8. The effect of delignification of forest biomass on enzymatic hydrolysis.

    Science.gov (United States)

    Yu, Zhiying; Jameel, Hasan; Chang, Hou-Min; Park, Sunkyu

    2011-10-01

    The effect of delignification methods on enzymatic hydrolysis of forest biomass was investigated using softwood and hardwood that were pretreated at an alkaline condition followed by sodium chlorite or ozone delignification. Both delignifications improved enzymatic hydrolysis especially for softwood, while pretreatment alone was found effective for hardwood. High enzymatic conversion was achieved by sodium chlorite delignification when the lignin content was reduced to 15%, which is corresponding to 0.30-0.35 g/g accessible pore volume, and further delignification showed a marginal effect. Sample crystallinity index increased with lignin removal, but it did not show a correlation with the overall carbohydrate conversion of enzymatic hydrolysis. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. 75 FR 5941 - Umatilla National Forest, Walla Walla Ranger District, Walla Walla, WA; Cobbler II Timber Sale...

    Science.gov (United States)

    2010-02-05

    ... timber harvest, including treatment of activity and natural fuels within harvest units, temporary road... show that old forest structure is within historical range for moist forest biophysical group, but outside of historical range for dry forest biophysical group in old forest single stratum (OFSS...

  10. Current near-to-nature forest management effects on functional trait composition of saproxylic beetles in beech forests.

    Science.gov (United States)

    Gossner, Martin M; Lachat, Thibault; Brunet, Jörg; Isacsson, Gunnar; Bouget, Christophe; Brustel, Hervé; Brandl, Roland; Weisser, Wolfgang W; Müller, Jörg

    2013-06-01

    With the aim of wood production with negligible negative effects on biodiversity and ecosystem processes, a silvicultural practice of selective logging with natural regeneration has been implemented in European beech forests (Fagus sylvatica) during the last decades. Despite this near-to-nature strategy, species richness of various taxa is lower in these forests than in unmanaged forests. To develop guidelines to minimize the fundamental weaknesses in the current practice, we linked functional traits of saproxylic beetle species to ecosystem characteristics. We used continental-scale data from 8 European countries and regional-scale data from a large forest in southern Germany and forest-stand variables that represented a gradient of intensity of forest use to evaluate the effect of current near-to-nature management strategies on the functional diversity of saproxylic beetles. Forest-stand variables did not have a statistically significant effect on overall functional diversity, but they did significantly affect community mean and diversity of single functional traits. As the amount of dead wood increased the composition of assemblages shifted toward dominance of larger species and species preferring dead wood of large diameter and in advanced stages of decay. The mean amount of dead wood across plots in which most species occurred was from 20 to 60 m(3) /ha. Species occurring in plots with mean dead wood >60 m(3) /ha were consistently those inhabiting dead wood of large diameter and in advanced stages of decay. On the basis of our results, to make current wood-production practices in beech forests throughout Europe more conservation oriented (i.e., promoting biodiversity and ecosystem functioning), we recommend increasing the amount of dead wood to >20 m(3) /ha; not removing dead wood of large diameter (50 cm) and allowing more dead wood in advanced stages of decomposition to develop; and designating strict forest reserves, with their exceptionally high amounts of

  11. Carbon dynamics in the future forest: the importance of long-term successional legacy and climate–fire interactions

    Science.gov (United States)

    Louise Loudermilk; Robert Scheller; Peter Weisberg; Jian Yang; Thomas Dilts; Sarah Karam; Carl Skinner

    2013-01-01

    Understanding how climate change may influence forest carbon (C) budgets requires knowledge of forest growth relationships with regional climate, long-term forest succession, and past and future disturbances, such as wildfires and timber harvesting events. We used a landscape-scale model of forest succession, wildfire, and C dynamics (LANDIS-II) to evaluate the effects...

  12. Anthropogenic Effects on Forest Ecosystems at Various Spatio-Temporal Scales

    Directory of Open Access Journals (Sweden)

    Michael Bredemeier

    2002-01-01

    Full Text Available The focus in this review of long-term effects on forest ecosystems is on human impact. As a classification of this differentiated and complex matter, three domains of long-term effects with different scales in space and time are distinguished: 1- Exploitation and conversion history of forests in areas of extended human settlement 2- Long-range air pollution and acid deposition in industrialized regions 3- Current global loss of forests and soil degradation.

  13. Evaluation of dentoskeletal effects of Farmand functional appliance (Fa II on class II malocclusion

    Directory of Open Access Journals (Sweden)

    Yassaei S.

    2007-07-01

    Full Text Available Background and Aim: Functional appliances refer to a variety of removable or fixed appliances designed to alter the mandibular position both sagitally and vertically, resulting in orthodontic and orthopedic changes. Despite the long history of functional appliances, there is still much controversy related to their effectiveness and mode of action. The aim of this study was to evaluate dental and skeletal effects of Fa II in patients with class II malocclusion due to mandibular deficiency.Materials and Methods: In this before-after clinical trial, 35 patients with class II div I malocclusion were selected. These samples were under treatment with Fa II appliance for 11 months. The range of age of females was 10-13 years and males 11-14 years. Combination analysis was used to determine skeletal and dental effects. Paired t-test was used to compare the differences of mean value pre and post treatment. P<0.05 was considered as the level of significance. Results: There was significant difference between pre and post treatment in respect to posterior and anterior facial height, eruption of upper and lower posterior teeth, eruption of upper anterior teeth, mandibular body length, ANB angle, IMPA and 1 to SN. No significant difference was observed between pre and post treatment regarding facial growth.Conclusion: Treatment with Fa II functional appliance leads to significant alterations in dental and skeletal elements of craniofacial complex and improvement of dental and jaws relationship.

  14. Solar radiation measurements in forests - II. methods based on the principle of hemispherical photography

    International Nuclear Information System (INIS)

    Diaci, J.; Kolar, U.; Thormann, J.-J.

    1999-01-01

    The know-how in the field of solar radiation distribution in forests is important for basic ecological investigations and silvicultural practice. Three methods of solar radiation assessment based on hemispherical canopy photography are compared in the present article: a hemispherical photography by means of a fish-eye lens, a horizontoscope and the ALI-2000 Plant Canopy Analyzer. Experiences, improved methods and a drawing of a horizontoscope stand which was elaborated at the Chair of Silviculture are presented. Fairly good results with some limitations can be achieved with the improved stable horizontoscope in silvicultural work. Hemispherical photography is appropriate for the assessment of light conditions in all stand types and can thus be used in research work. The method has recently been undergoing intensive development. Digitalization of the entire system will speed up standardization. The ALI-2000 instrument is highly suitable for regeneration research in conditions of abundant plant vegetation, in reach sites and modified stands [sl

  15. Multiple metrics of diversity have different effects on temperate forest functioning over succession.

    Science.gov (United States)

    Yuan, Zuoqiang; Wang, Shaopeng; Gazol, Antonio; Mellard, Jarad; Lin, Fei; Ye, Ji; Hao, Zhanqing; Wang, Xugao; Loreau, Michel

    2016-12-01

    Biodiversity can be measured by taxonomic, phylogenetic, and functional diversity. How ecosystem functioning depends on these measures of diversity can vary from site to site and depends on successional stage. Here, we measured taxonomic, phylogenetic, and functional diversity, and examined their relationship with biomass in two successional stages of the broad-leaved Korean pine forest in northeastern China. Functional diversity was calculated from six plant traits, and aboveground biomass (AGB) and coarse woody productivity (CWP) were estimated using data from three forest censuses (10 years) in two large fully mapped forest plots (25 and 5 ha). 11 of the 12 regressions between biomass variables (AGB and CWP) and indices of diversity showed significant positive relationships, especially those with phylogenetic diversity. The mean tree diversity-biomass regressions increased from 0.11 in secondary forest to 0.31 in old-growth forest, implying a stronger biodiversity effect in more mature forest. Multi-model selection results showed that models including species richness, phylogenetic diversity, and single functional traits explained more variation in forest biomass than other candidate models. The models with a single functional trait, i.e., leaf area in secondary forest and wood density in mature forest, provided better explanations for forest biomass than models that combined all six functional traits. This finding may reflect different strategies in growth and resource acquisition in secondary and old-growth forests.

  16. Effect of Corrupt Behavior of the Forestry Bureaucrats on the Forest Sustainability

    Directory of Open Access Journals (Sweden)

    Sudarsono Soedomo

    2012-11-01

    Full Text Available 800x600 This article show that corrupt bureaucrats do not always result in a negative effect on the forest sustainability. Even under a certain condition, a corrupt behavior may result in a positive effect on the forest sustainability. An inappropriate policy is more important a cause of the forest sustainability than a corrupt behavior. Therefore, fixing this structural mistake needs to be prioritized in combating the forest destruction, for this structural mistake is the real primary cause of the forest destruction in Indonesia. Fixing this structural mistake is much more effective in combating the forest destruction than finding honest bureaucrats. Keywords:     Birokrat, Distortionary, Nondistortionary, Kelestarian, Korup. Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4

  17. Effects of forest management on California Spotted Owls: implications for reducing wildfire risk in fire‐prone forests.

    Science.gov (United States)

    Tempel, Douglas J; Gutiérrez, R J; Whitmore, Sheila A; Reetz, Matthew J; Stoelting, Ricka E; Berigan, William J; Seamans, Mark E; Zachariah Peery, M

    Management of many North American forests is challenged by the need to balance the potentially competing objectives of reducing risks posed by high-severity wildfires and protecting threatened species. In the Sierra Nevada, California, concern about high-severity fires has increased in recent decades but uncertainty exists over the effects of fuel-reduction treatments on species associated with older forests, such as the California Spotted Owl (Strix occidentalis occidentalis). Here, we assessed the effects of forest conditions, fuel reductions, and wildfire on a declining population of Spotted Owls in the central Sierra Nevada using 20 years of demographic data collected at 74 Spotted Owl territories. Adult survival and territory colonization probabilities were relatively high, while territory extinction probability was relatively low, especially in territories that had relatively large amounts of high canopy cover (≥70%) forest. Reproduction was negatively associated with the area of medium-intensity timber harvests characteristic of proposed fuel treatments. Our results also suggested that the amount of edge between older forests and shrub/sapling vegetation and increased habitat heterogeneity may positively influence demographic rates of Spotted Owls. Finally, high-severity fire negatively influenced the probability of territory colonization. Despite correlations between owl demographic rates and several habitat variables, life stage simulation (sensitivity) analyses indicated that the amount of forest with high canopy cover was the primary driver of population growth and equilibrium occupancy at the scale of individual territories. Greater than 90% of medium-intensity harvests converted high-canopy-cover forests into lower-canopy-cover vegetation classes, suggesting that landscape-scale fuel treatments in such stands could have short-term negative impacts on populations of California Spotted Owls. Moreover, high-canopy-cover forests declined by an average of

  18. Effects of changes in the riparian forest on the butterfly community (Insecta: Lepidoptera in Cerrado areas

    Directory of Open Access Journals (Sweden)

    Helena S.R. Cabette

    Full Text Available ABSTRACT Preserved riparian vegetation usually has greater environmental complexity than the riparian vegetation modified by human actions. These systems may have a greater availability and diversity of food resources for the species. Our objective was to evaluate the effect of changes on the structure of the riparian forest on species richness, beta diversity and composition of butterfly species in the Cerrado of Mato Grosso. We tested the hypotheses that: (i higher species richness and (ii beta diversity would be recorded in more preserved environments; and (iii species composition would be more homogeneous in disturbed habitats. For hypothesis testing, the riparian vegetation of eight streams were sampled in four periods of the year in a fixed transect of 100 m along the shores. The richness of butterfly species is lower in disturbed than in preserved areas. However, species richness is not affected by habitat integrity. Beta diversity differed among sites, such that preserved sites have greater beta diversity, showing greater variation in species composition. In addition, beta diversity was positively affected by environmental heterogeneity. A total of 23 of the 84 species sampled occurred only in the changed environment, 42 were exclusive to preserved sites and 19 occurred in both environments. The environmental change caused by riparian forest removal drastically affects the butterfly community. Therefore, riparian vegetation is extremely important for butterfly preservation in the Cerrado and may be a true biodiversity oasis, especially during the dry periods, when the biome undergoes water stress and resource supply is more limited.

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

    Science.gov (United States)

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

    2009-02-01

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

  20. Short-Term Effects of Understory and Overstory Management on Breeding Birds in Arkansas Oak-Hickory Forests

    Science.gov (United States)

    Paul G. Rodewald; Kimberly G. Smith

    1998-01-01

    Relatively little is known about the effects of uneven-aged forest management practices on eastern forest birds, despite the fact that such methods are now commonly practiced. In 1993-94, we studied the short-term effects of uneven-aged forest management on bird communities in oak-hickory forests of north-western Arkansas. We estimated bird abundance in mature forests...

  1. Landscape genetic analyses reveal fine-scale effects of forest fragmentation in an insular tropical bird.

    Science.gov (United States)

    Khimoun, Aurélie; Peterman, William; Eraud, Cyril; Faivre, Bruno; Navarro, Nicolas; Garnier, Stéphane

    2017-10-01

    Within the framework of landscape genetics, resistance surface modelling is particularly relevant to explicitly test competing hypotheses about landscape effects on gene flow. To investigate how fragmentation of tropical forest affects population connectivity in a forest specialist bird species, we optimized resistance surfaces without a priori specification, using least-cost (LCP) or resistance (IBR) distances. We implemented a two-step procedure in order (i) to objectively define the landscape thematic resolution (level of detail in classification scheme to describe landscape variables) and spatial extent (area within the landscape boundaries) and then (ii) to test the relative role of several landscape features (elevation, roads, land cover) in genetic differentiation in the Plumbeous Warbler (Setophaga plumbea). We detected a small-scale reduction of gene flow mainly driven by land cover, with a negative impact of the nonforest matrix on landscape functional connectivity. However, matrix components did not equally constrain gene flow, as their conductivity increased with increasing structural similarity with forest habitat: urban areas and meadows had the highest resistance values whereas agricultural areas had intermediate resistance values. Our results revealed a higher performance of IBR compared to LCP in explaining gene flow, reflecting suboptimal movements across this human-modified landscape, challenging the common use of LCP to design habitat corridors and advocating for a broader use of circuit theory modelling. Finally, our results emphasize the need for an objective definition of landscape scales (landscape extent and thematic resolution) and highlight potential pitfalls associated with parameterization of resistance surfaces. © 2017 John Wiley & Sons Ltd.

  2. Effect of Extreme Drought on Tropical Dry Forests

    Science.gov (United States)

    Castro, Saulo; Sanchez-Azofeifa, Arturo; Sato, Hiromitsu; Cowling, Sharon; Vega-Araya, Mauricio

    2017-04-01

    Tropical dry forests (TDFs) hold a strong economic and cultural connection to human development in the Neotropics. Historically, TDFs not only represent a source of agricultural and urban land but also an important source of goods and ecosystem services for the communities that live around them. Such is the close connection of TDFs to human activity that they are considered the most heavily utilized and disturbed ecosystem in the world. However, TDF have been largely understudied and represent only a fraction of research devoted to globally tropical ecosystems. Thus we lack the framework to properly project how predicted increases in drought events due to climate change will impact TDFs and human society which depend on its services. Our study aims to show the effect of extreme drought on water, food security, and tropical dry forest productivity in the Guanacaste province of Costa Rica. Two pre-ENSO years (2013-2014) and an ENSO year (2015) were compared. The 2013 and 2014 pre-ENSO years were classified as a normal precipitation (1470 mm) and drought year (1027mm), respectively. The 2015 ENSO year was classified as a severe drought (654mm), with amplified effects resulting by the drought experienced during the previous (2014) growing cycle. Effects of the ENSO drought on agriculture and livestock sectors in the province included losses of US13million and US6.5million, respectively. Crop land losses equaled 2,118 hectares and 11,718 hectares were affected. Hydroelectricity generation decreased by 10% and potable water shortages were observed. The Agriculture and Livestock Ministry (MAG) and the National Emergency Commission (CNE) distributed animal feed and supplies to 4,000 farmers affected by the extreme droughts. Eddy covariance flux measurements were used to identify productivity changes during the extreme drought. Changes in phenologic stages and the transitions between CO2 sink to source during mid-growing cycle were observed. Drought significantly delayed

  3. Long-term effects of prescribed fire on mixed conifer forest structure in the Sierra Nevada, California

    Science.gov (United States)

    Phillip J. Van Mantgem; Nathan L. Stephenson; Eric Knapp; John Barrles; Jon E. Keeley

    2011-01-01

    The capacity of prescribed fire to restore forest conditions is often judged by changes in forest structure within a few years following burning. However, prescribed fire might have longer-term effects on forest structure, potentially changing treatment assessments. We examined annual changes in forest structure in five 1 ha old-growth plots immediately before...

  4. Effects of tropical montane forest disturbance on epiphytic macrolichens

    Energy Technology Data Exchange (ETDEWEB)

    Benitez, Angel [Instituto de Ecologia, Herbario HUTPL, Universidad Tecnica Particular de Loja, San Cayetano s/n, Loja (Ecuador); Prieto, Maria, E-mail: maria.prieto@urjc.es [Area de Biodiversidad y Conservacion, ESCET, Universidad Rey Juan Carlos, Mostoles, E-28933, Madrid (Spain); Gonzalez, Yadira [Instituto de Ecologia, Herbario HUTPL, Universidad Tecnica Particular de Loja, San Cayetano s/n, Loja (Ecuador); Aragon, Gregorio [Area de Biodiversidad y Conservacion, ESCET, Universidad Rey Juan Carlos, Mostoles, E-28933, Madrid (Spain)

    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. -- Highlights: Black-Right-Pointing-Pointer Tropical montane forest disturbance drastically reduced macrolichen diversity. Black-Right-Pointing-Pointer Species loss was most severe for the 'shade-adapted lichens' because high radiation is harmful to them. Black-Right-Pointing-Pointer In secondary forests lichen diversity of native forests was not regenerated. Black-Right-Pointing-Pointer The protection of remnants of primary tropical forest might help to preserve a diverse community of epiphytic macrolichens.

  5. Green infrastructure development at European Union's eastern border: Effects of road infrastructure and forest habitat loss.

    Science.gov (United States)

    Angelstam, Per; Khaulyak, Olha; Yamelynets, Taras; Mozgeris, Gintautas; Naumov, Vladimir; Chmielewski, Tadeusz J; Elbakidze, Marine; Manton, Michael; Prots, Bohdan; Valasiuk, Sviataslau

    2017-05-15

    The functionality of forest patches and networks as green infrastructure may be affected negatively both by expanding road networks and forestry intensification. We assessed the effects of (1) the current and planned road infrastructure, and (2) forest loss and gain, on the remaining large forest landscape massifs as green infrastructure at the EU's eastern border region in post-socialistic transition. First, habitat patch and network functionality in 1996-98 was assessed using habitat suitability index modelling. Second, we made expert interviews about road development with planners in 10 administrative regions in Poland, Belarus and Ukraine. Third, forest loss and gain inside the forest massifs, and gain outside them during the period 2001-14 were measured. This EU cross-border region hosts four remaining forest massifs as regional green infrastructure hotspots. While Poland's road network is developing fast in terms of new freeways, city bypasses and upgrades of road quality, in Belarus and Ukraine the focus is on maintenance of existing roads, and no new corridors. We conclude that economic support from the EU, and thus rapid development of roads in Poland, is likely to reduce the permeability for wildlife of the urban and agricultural matrix around existing forest massifs. However, the four identified forest massifs themselves, forming the forest landscape green infrastructure at the EU's east border, were little affected by road development plans. In contrast, forest loss inside massifs was high, especially in Ukraine. Only in Poland forest loss was balanced by gain. Forest gain outside forest massifs was low. To conclude, pro-active and collaborative spatial planning across different sectors and countries is needed to secure functional forest green infrastructure as base for biodiversity conservation and human well-being. Copyright © 2017. Published by Elsevier Ltd.

  6. Local cooling and warming effects of forests based on satellite observations

    Science.gov (United States)

    Li, Yan; Zhao, Maosheng; Motesharrei, Safa; Mu, Qiaozhen; Kalnay, Eugenia; Li, Shuangcheng

    2015-01-01

    The biophysical effects of forests on climate have been extensively studied with climate models. However, models cannot accurately reproduce local climate effects due to their coarse spatial resolution and uncertainties, and field observations are valuable but often insufficient due to their limited coverage. Here we present new evidence acquired from global satellite data to analyse the biophysical effects of forests on local climate. Results show that tropical forests have a strong cooling effect throughout the year; temperate forests show moderate cooling in summer and moderate warming in winter with net cooling annually; and boreal forests have strong warming in winter and moderate cooling in summer with net warming annually. The spatiotemporal cooling or warming effects are mainly driven by the two competing biophysical effects, evapotranspiration and albedo, which in turn are strongly influenced by rainfall and snow. Implications of our satellite-based study could be useful for informing local forestry policies. PMID:25824529

  7. Determination of static and dynamic reactivity effects in KNK II

    International Nuclear Information System (INIS)

    Essig, C.

    1987-11-01

    In the frame of a pre-study of the KNK II test program two series of experiments related to inherent safety characteristics of sodium cooled breeder reactors have been elaborated, which are one basis for the performance of experiments of the Loss Of Flow (LOF) type and the Loss Of Heat Sink (LOHS) type. Tests of this type at KNK II would -different from the earlier tests at RAPSODIE and EBR-II- provide a demonstration of the inherently safe performance in case of a significantly non-zero Doppler effect. With a suitable execution, the foreseen series of experiments allow, as explained in this report, a substantial separation of the reactivity contributions and the determination of reactivity effects, i.e. the time constants of the recouplings. The performance and evaluation of these experiments with respect to the inherent safety potential will once more underline the distinguished role of KNK II for the development of fast breeders [de

  8. Removal of Pb(II), Cd(II), Cu(II), and Zn(II) by hematite nanoparticles: effect of sorbent concentration, pH, temperature, and exhaustion.

    Science.gov (United States)

    Shipley, Heather J; Engates, Karen E; Grover, Valerie A

    2013-03-01

    Nanoparticles offer the potential to improve environmental treatment technologies due to their unique properties. Adsorption of metal ions (Pb(II), Cd(II), Cu(II), Zn(II)) to nanohematite was examined as a function of sorbent concentration, pH, temperature, and exhaustion. Adsorption experiments were conducted with 0.05, 0.1, and 0.5 g/L nanoparticles in a pH 8 solution and in spiked San Antonio tap water. The adsorption data showed the ability of nanohematite to remove Pb, Cd, Cu, and Zn species from solution with adsorption increasing as the nanoparticle concentration increased. At 0.5 g/L nanohematite, 100 % Pb species adsorbed, 94 % Cd species adsorbed, 89 % Cu species adsorbed and 100 % Zn species adsorbed. Adsorption kinetics for all metals tested was described by a pseudo second-order rate equation with lead having the fastest rate of adsorption. The effect of temperature on adsorption showed that Pb(II), Cu(II), and Cd(II) underwent an endothermic reaction, while Zn(II) underwent an exothermic reaction. The nanoparticles were able to simultaneously remove multiple metals species (Zn, Cd, Pb, and Cu) from both a pH 8 solution and spiked San Antonio tap water. Exhaustion experiments showed that at pH 8, exhaustion did not occur for the nanoparticles but adsorption does decrease for Cd, Cu, and Zn species but not Pb species. The strong adsorption coupled with the ability to simultaneously remove multiple metal ions offers a potential remediation method for the removal of metals from water.

  9. Effectiveness of best management practices that have application to forest roads: a literature synthesis

    Science.gov (United States)

    Pamela J. Edwards; Frederica Wood; Robin L. Quinlivan

    2016-01-01

    Literature describing the effectiveness of best management practices (BMPs) applicable to forest roads is reviewed and synthesized. Effectiveness is considered from the perspective of protecting water quality and water resources. Both paved and unpaved forest roads are considered, but BMPs that involve substantial engineering are not considered. Some of the BMPs...

  10. Headwater streams and forest management: Does ecoregional context influence logging effects on benthic communities?

    Science.gov (United States)

    R. Bruce Medhurst; Mark S. Wipfli; Chris Binckley; Karl Polivka; Paul F. Hessburg; R. Brion. Salter

    2010-01-01

    Effects of forest management on stream communities have been widely documented, but the role that climate plays in the disturbance outcomes is not understood. In order to determine whether the effect of disturbance from forest management on headwater stream communities varies by climate, we evaluated benthic macroinvertebrate communities in 24 headwater streams that...

  11. Detecting the effects of forest harvesting on streamflow using hydrologic model change detection

    Science.gov (United States)

    Nicolas P. Zegre; Nicholas A. Som

    2011-01-01

    Knowledge of the effects of forest management on hydrology primarily comes from paired-catchment study experiments. This approach has contributed fundamental knowledge of the effects of forest management on hydrology, but results from these studies lack insight into catchment processes. Outlined in this study is an alternative method of change detection that uses a...

  12. Effects of long-term deforestation and remnant forests on rainfall and temperature in the Central Rift Valley of Ethiopia

    Directory of Open Access Journals (Sweden)

    Alemayehu Muluneh

    2017-11-01

    Full Text Available Background Some evidence suggests that forests attract rain and that deforestation contributes to changes in rainfall and temperature. The evidence, however, is scant, particularly on smaller spatial scales. The specific objectives of the study were: (i to evaluate long-term trends in rainfall (1970–2009 and temperature (1981–2009 and their relationships with change in forest cover, and (ii to assess the influence of remnant forests and topographical factors on the spatial variability of annual rainfall. Methods This study investigated the forest-rainfall relationships in the Central Rift Valley of Ethiopia. The study used 16 long-term (1970–2009 and 15 short-term (2012–2013 rainfall and six long term (1981–2009 temperature datasets. Forest and woodland cover decline over the past 40 years (1970–2009 and the measured distances between the remnant forests and rainfall stations were also used. The long-term trends in rainfall (1970–2009 and temperature (1981–2009 were determined using Mann-Kendall (MK and Regional Kendall (RK tests and their relationships with long-term deforestation were evaluated using simple linear regression. Influence of remnant forests and topographical variables on the spatial variability of rainfall were determined by stepwise multiple regression method. A continuous forest and woodland cover decline was estimated using exponential interpolation. Results The forest and woodland cover declined from 44% in 1973 to less than 15% in 2009 in the Central Rift Valley. Annual rainfall on the valley floor showed an increase by 37.9 mm/decade while annual rainfall on the escarpments/highlands decreased by 29.8 mm/decade. The remnant forests had a significant effect (P-value <0.05, R 2 = 0.40 on the spatial variability of the number of rainy days observed over two years (2012–2013, but had little effect on the variability of rainfall distribution. For the total annual rainfall, slope was the best predictor which

  13. Testing the Amazon savannization hypothesis: fire effects on invasion of a neotropical forest by native cerrado and exotic pasture grasses.

    Science.gov (United States)

    Silvério, Divino V; Brando, Paulo M; Balch, Jennifer K; Putz, Francis E; Nepstad, Daniel C; Oliveira-Santos, Claudinei; Bustamante, Mercedes M C

    2013-06-05

    Changes in climate and land use that interact synergistically to increase fire frequencies and intensities in tropical regions are predicted to drive forests to new grass-dominated stable states. To reveal the mechanisms for such a transition, we established 50 ha plots in a transitional forest in the southwestern Brazilian Amazon to different fire treatments (unburned, burned annually (B1yr) or at 3-year intervals (B3yr)). Over an 8-year period since the commencement of these treatments, we documented: (i) the annual rate of pasture and native grass invasion in response to increasing fire frequency; (ii) the establishment of Brachiaria decumbens (an African C4 grass) as a function of decreasing canopy cover and (iii) the effects of grass fine fuel on fire intensity. Grasses invaded approximately 200 m from the edge into the interiors of burned plots (B1yr: 4.31 ha; B3yr: 4.96 ha) but invaded less than 10 m into the unburned plot (0.33 ha). The probability of B. decumbens establishment increased with seed availability and decreased with leaf area index. Fine fuel loads along the forest edge were more than three times higher in grass-dominated areas, which resulted in especially intense fires. Our results indicate that synergies between fires and invasive C4 grasses jeopardize the future of tropical forests.

  14. COLLECTIVE EFFECTS IN THE NSLS-II STORAGE RING

    International Nuclear Information System (INIS)

    KRINSKY, S.; BENGTSSON, J.; BERG, J.S.; BLASKIEWICZ, M.; BLEDNYKH, A.; GUO, W.; MALITSKY, N.; MONTAG, C.; PODOBEDOV, B.; ROSE, J.; TOWNE, N.; YU, L.H.

    2007-01-01

    A new high-brightness synchrotron light source (NSLS-II) is under design at BNL. The 3-GeV NSLS-II storage ring has a double-bend achromatic lattice with damping wigglers installed in zero-dispersion straights to reduce the emittance below 1nm. In this paper, we present an overview of the impact of collective effects upon the performance of the storage ring. Subjects discussed include instability thresholds, Touschek lifetime and intra-beam scattering

  15. COLLECTIVE EFFECTS IN THE NSLS-II STORAGE RING.

    Energy Technology Data Exchange (ETDEWEB)

    KRINSKY,S.; BENGTSSON, J.; BERG, J.S.; BLASKIEWICZ, M.; BLEDNYKH, A.; GUO, W.; MALITSKY, N.; MONTAG, C.; PODOBEDOV, B.; ROSE, J.; TOWNE, N.; YU, L.H.

    2007-06-25

    A new high-brightness synchrotron light source (NSLS-II) is under design at BNL. The 3-GeV NSLS-II storage ring has a double-bend achromatic lattice with damping wigglers installed in zero-dispersion straights to reduce the emittance below 1nm. In this paper, we present an overview of the impact of collective effects upon the performance of the storage ring. Subjects discussed include instability thresholds, Touschek lifetime and intra-beam scattering.

  16. Climate change effects on native fauna of northeastern forests

    Energy Technology Data Exchange (ETDEWEB)

    Rodenhouse, N.L. [Wellesley College, Wellesley, MA (United States). Dept. of Biological Sciences; Christenson, L.M. [Cary Inst. of Ecosystem Studies, Millbrook, NY (United States); Parry, D. [SUNY College of Environmental Science and Forestry, Syracuse, NY (United States). Dept. of Environmental and Forest Biology; Green, L.E. [Georgia Inst. of Technology, Atlanta, GA (United States). School of Biology

    2009-02-15

    This study investigated the impacts of climate change on the native fauna of northeastern forests in North America. The assessment of birds, mammals, amphibians, and insects used recent regional-scale climate projections in order to understand potential impacts on the distribution and abundance of various wildlife species. The study demonstrated that alterations in precipitation and temperature regimes will affect species directly and indirectly in each of the studied taxa. Climate change impacts in the winter will have a significant impact on the survival, distribution, and abundance of hibernating mammals, amphibians, birds, and diapausing insects. The effects of climate change under low emission scenarios will have a profound impact on iconic and endangered species, as well as on species that pollinate and regulate insect populations. Targeted research is needed in order to develop quantitative and geographically relevant projections. It was concluded that further research is needed to identify causal mechanisms in population and community-level processes. 185 refs.

  17. Sex differences in the drinking response to angiotensin II (AngII): Effect of body weight.

    Science.gov (United States)

    Santollo, Jessica; Torregrossa, Ann-Marie; Daniels, Derek

    2017-07-01

    Sex differences in fluid intake stimulated by angiotensin II (AngII) have been reported, but the direction of the differences is inconsistent. To resolve these discrepancies, we measured water intake by male and female rats given AngII. Males drank more than females, but when intake was normalized to body weight, the sex difference was reversed. Weight-matched males and females, however, had no difference in intake. Using a linear mixed model analysis, we found that intake was influenced by weight, sex, and AngII dose. We used linear regression to disentangle these effects further. Comparison of regression coefficients revealed sex and weight differences at high doses of AngII. Specifically, after 100ng AngII, weight was a predictor of intake in males, but not in females. Next, we tested for differences in AngII-induced intake in male and females allowed to drink both water and saline. Again, males drank more water than females, but females showed a stronger preference for saline. Drinking microstructure analysis suggested that these differences were mediated by postingestive signals and more bottle switches by the females. Finally, we probed for differences in the expression of components of the renin-angiotensin system in the brains of males and females and found sex differences in several genes in discrete brain regions. These results provide new information to help understand key sex differences in ingestive behaviors, and highlight the need for additional research to understand baseline sex differences, particularly in light of the new NIH initiative to balance sex in biomedical research. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Effects of white-tailed deer and invasive plants on the herb layer of suburban forests.

    Science.gov (United States)

    Morrison, Janet A

    2017-11-01

    Lack of hunting and predators and proximity to human communities make suburban forests prone to high deer abundance and non-native plant invasions. I investigated these likely drivers of community structure in the herb layers of six suburban forests in one region of New Jersey, USA. In 223 plots I assessed the herb layer response to 2.5 years with or without deer fencing and the early stage of invasion from seed additions of Microstegium vimineum , an invasive, annual grass. Non-native plants and herbaceous native plants were affected very little by fencing or M. vimineum invasion. In contrast, across all forests the combination of deer access and M. vimineum addition had a strongly negative effect on woody native percent cover. Forests differed in overall fencing effects on woody natives; their cover was greater in fenced plots in just three forests, suggesting greater deer pressure in those forests during the experiment. The early invasion by M. vimineum was greatest in two of these same forests, but was not influenced by fencing. Multi-group structural equation modelling compared two groups of forests that differed in vegetation abundance and other characteristics. It paralleled the results above and also showed no negative influence of non-native cover on native cover, even in the forests where non-native cover was greater. It identified a positive effect of light level on herb layer plants in the forests with less vegetation, and also revealed a positive effect of soil water potential (SWP) on non-native plants in the forests with more vegetation, which had higher SWP. These suburban forests within a common region varied widely in native and non-native herb layer abundance, the early success of M. vimineum invasion and the herb layer's response to early invasion and protection from deer.

  19. Effects of Burn Severity and Environmental Conditions on Post-Fire Regeneration in Siberian Larch Forest

    OpenAIRE

    Thuan Chu; Xulin Guo; Kazuo Takeda

    2017-01-01

    Post-fire forest regeneration is strongly influenced by abiotic and biotic heterogeneity in the pre- and post-fire environments, including fire regimes, species characteristics, landforms, hydrology, regional climate, and soil properties. Assessing these drivers is key to understanding the long-term effects of fire disturbances on forest succession. We evaluated multiple factors influencing patterns of variability in a post-fire boreal Larch (Larix sibirica) forest in Siberia. A time-series o...

  20. Post-Crackdown Effectiveness of Field-Based Forest Law Enforcement in the Brazilian Amazon

    OpenAIRE

    B?rner, Jan; Kis-Katos, Krisztina; Hargrave, Jorge; K?nig, Konstantin

    2015-01-01

    Regulatory enforcement of forest conservation laws is often dismissed as an ineffective approach to reducing tropical forest loss. Yet, effective enforcement is often a precondition for alternative conservation measures, such as payments for environmental services, to achieve desired outcomes. Fair and efficient policies to reducing emissions from deforestation and forest degradation (REDD) will thus crucially depend on understanding the determinants and requirements of enforcement effectiven...

  1. Quantifying scaling effects on satellite-derived forest area estimates for the conterminous USA

    Science.gov (United States)

    Daolan Zheng; L.S. Heath; M.J. Ducey; J.E. Smith

    2009-01-01

    We quantified the scaling effects on forest area estimates for the conterminous USA using regression analysis and the National Land Cover Dataset 30m satellite-derived maps in 2001 and 1992. The original data were aggregated to: (1) broad cover types (forest vs. non-forest); and (2) coarser resolutions (1km and 10 km). Standard errors of the model estimates were 2.3%...

  2. Effect of nano-SiO II on bismaleimide composite

    Science.gov (United States)

    Geng, Dongbing; Zeng, Liming; Li, Yi; Fu, Qiuzhou; Hu, Bing

    2007-07-01

    This paper is concerned with the effect of nano-SiO II particles on the thermal stability and mechanical behavior of composite materials. A nano-composite of three components is prepared by polymerizing nano-SiO II, chopped carbon fiber and bismalemide resin. The investigation's basic approach involves a blend of experimental and analytical studies to determine structure/property relationship. Nano-composite structures are characterized by dynamic mechanical analysis, and contents of nano-SiO II are subsequently correlated with mechanical properties such as tensile and flexural strength also the modulus. The results indicate that the content of nano-SiO II exhibits significant improvement on glass transition temperature (Tg) with Tg elevation by increasing concentration of nano-SiO II. The higher Tg is the result of steric hindrance by nano-SiO II particles in the nano-composite. The mechanical properties of the tensile and flexural strength are raised at first and followed by decreasing as the amount of nano-SiO II particles increased. All the modulus values mimic the tensile and flexural strength.

  3. Inhibitory effect of tanshinone II A on TGF II-β1-induced cardiac fibrosis.

    Science.gov (United States)

    Zhou, Daixing; Li, Zhihui; Zhang, Liwei; Zhan, Chengye

    2012-12-01

    This study examined the effect of tanshinone II A (TSN II A) on the cardiac fibrosis induced by transforming growth factor β1 (TGF-β1) and the possible mechanisms. Cardiac fibroblasts were isolated from cardiac tissues of neonatal Sprague-Dawley (SD) rats by the trypsin digestion and differential adhesion method. The cells were treated with 5 ng/mL TGF-β1 alone or pretreated with TSN II A at different concentrations (10(-5) mol/L, 10(-4) mol/L). Immunocytochemistry was used for cell identification, RT-PCR for detection of the mRNA expression of connective tissue growth factor (CTGF) and collagen type I (COL I), Western blotting for detection of the protein expression of Smad7 and Smad3, and immunohistochemistry and immunofluorescence staining for detection of the protein expression of phosphorylated Smad3 (p-Smad3), CTGF and COLI. The results showed that TGF-β1 induced the expression of CTGF, COL I, p-Smad3 and Smad7 in a time-dependent manner. The mRNA expression of CTGF and COL I was significantly increased 24 h after TGF-β1 stimulation (PTSN A resulted in a decrease in the expression of p-Smad3, CTGF and COL I (PTSN II A as compared with that at 2 h post TGF-β1 stimulation (PTSN I IA; PTSN II A). It was concluded that TSN II A may exert an inhibitory effect on cardiac fibrosis by upregulating the expression of Smad7, suppressing the TGF-β1-induced phosphorylation of Smad3 and partially blocking the TGF-β1-Smads signaling pathway.

  4. Modeling forest defoliation using simulated BRDF and assessing its effect on reflectance and sensor reaching radiance

    Science.gov (United States)

    Rengarajan, Rajagopalan; Schott, John R.

    2016-09-01

    Remote sensing techniques such as change detection are widely used for mapping and monitoring forest cover to detect the declining health and vigor of forests. These techniques rely on the assumption that the biophysical variation in the forest introduces a corresponding variation in its reflectance. The biophysical variations are assessed by foresters, but these assessment techniques are expensive and cannot be performed frequently to identify a specific level of change in the forest, for example, infection due to gypsy moths that results in forest defoliation. Further, the interaction of atmosphere, sensor characteristics, and phenology that are inherent in the remotely sensed images makes it difficult to separate biophysical changes from observational effects. We have addressed these limitations by developing a method to model the spectral reflectance properties of forests with varying degrees of defoliation using the Digital Image and Remote Sensing Image Generation (DIRSIG) tool. This paper discusses the in-canopy radiative approach and the impact of defoliation on the reflectance and radiance observed by sensors such as Landsat. The results indicate that the relative variation in forest reflectance between a non-defoliated and a 30% defoliated deciduous forest can be as high as 10% in the NIR spectral band. A function can be fit to predict the level of defoliation from the relative variation in radiance. The modeling and analysis techniques can be extended to assess the impact of atmospheric factors and sensor characteristics relative to the biophysical changes as well as for assessing other biophysical variables in forests.

  5. Edge effects on N2O, NO and CH4 fluxes in two temperate forests.

    Science.gov (United States)

    Remy, Elyn; Gasche, Rainer; Kiese, Ralf; Wuyts, Karen; Verheyen, Kris; Boeckx, Pascal

    2017-01-01

    Forest ecosystems may act as sinks or sources of nitrogen (N) and carbon (C) compounds, such as the climate relevant trace gases nitrous oxide (N 2 O), nitric oxide (NO) and methane (CH 4 ). Forest edges, which catch more atmospheric deposition, have become important features in European landscapes and elsewhere. Here, we implemented a fully automated measuring system, comprising static and dynamic measuring chambers determining N 2 O, NO and CH 4 fluxes along an edge-to-interior transect in an oak (Q. robur) and a pine (P. nigra) forest in northern Belgium. Each forest was monitored during a 2-week measurement campaign with continuous measurements every 2h. NO emissions were 9-fold higher than N 2 O emissions. The fluxes of NO and CH 4 differed between forest edge and interior, but not for N 2 O. This edge effect was more pronounced in the oak than in the pine forest. In the oak forest, edges emitted less NO (on average 60%) and took up more CH 4 (on average 177%). This suggests that landscape structure can play a role in the atmospheric budgets of these climate relevant trace gases. Soil moisture variation between forest edge and interior was a key variable explaining the magnitude of NO and CH 4 fluxes in our measurement campaign. To better understand the environmental impact of N and C trace gas fluxes from forest edges, additional and long-term measurements in other forest edges are required. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Is the seasonal forest more vulnerable to drought effects in tropical Amazonia

    Science.gov (United States)

    Xu, L.; Saatchi, S. S.; Yang, Y.

    2015-12-01

    Recent studies have found that the seasonal forests in semi-arid region are more susceptible to severe drought events and the persistent effect of these climate extremes can last for 2 to 4 years. However, the Amazonian forests, where the plant available water is often abundant, seasonal forests are considered more drought-tolerant as water deficits coincide with seasonal peaks of solar radiation. But the interactions between climate and anthropogenic changes have made the scenario of these forests in the "arc of deforestation" complicated. The tight coupling between extreme droughts and fire intensity can cause widespread fire-induced tree mortality across southeastern Amazon forests. The legacy effects of droughts, as well as the frequent revisit of these extremes in the recent decade (e.g. the 2005 and 2010 Amazon droughts) have made the projection of forest recovery unclear. In this study, we use satellite proxies of canopy structure, skin temperature and water content from observations of MODIS NIR reflectance, land surface temperature and QSCAT radar backscatter to define the seasonality in the Amazonian forests. It is further calibrated using the measurements of chlorophyll fluorescence from GOSAT, terrestrial water storage from GRACE, as well as the structural metrics from GLAS waveforms. We delineate the post-drought effects of Amazon forests using seasonality-derived phenological regions. The results are expected to have a better understanding of the inter-annual variation of forest seasonality under the influence of both climate extremes and human-induced changes.

  7. Integrated effects of air pollution and climate change on forests: a northern hemisphere perspective.

    Science.gov (United States)

    Bytnerowicz, Andrzej; Omasa, Kenji; Paoletti, Elena

    2007-06-01

    Many air pollutants and greenhouse gases have common sources, contribute to radiative balance, interact in the atmosphere, and affect ecosystems. The impacts on forest ecosystems have been traditionally treated separately for air pollution and climate change. However, the combined effects may significantly differ from a sum of separate effects. We review the links between air pollution and climate change and their interactive effects on northern hemisphere forests. A simultaneous addressing of the air pollution and climate change effects on forests may result in more effective research, management and monitoring as well as better integration of local, national and global environmental policies.

  8. Fertilization of Earth Ponds. II: Effects on Plankton Communities ...

    African Journals Online (AJOL)

    Fertilization of Earth Ponds. II: Effects on Plankton Communities. J. W. WADE, H. P. STIRLING. Abstract. A study of the effects of slurry inorganic and organic of fertilizers on the production of phyto-and zooplankton in earth ponds was conducted in Central Scotland, U.K. over a period of one year. For the inorganic fertilization, ...

  9. Positive edge effects on forest-interior cryptogams in clear-cuts.

    Directory of Open Access Journals (Sweden)

    Alexandro Caruso

    Full Text Available Biological edge effects are often assessed in high quality focal habitats that are negatively influenced by human-modified low quality matrix habitats. A deeper understanding of the possibilities for positive edge effects in matrix habitats bordering focal habitats (e.g. spillover effects is, however, essential for enhancing landscape-level resilience to human alterations. We surveyed epixylic (dead wood inhabiting forest-interior cryptogams (lichens, bryophytes, and fungi associated with mature old-growth forests in 30 young managed Swedish boreal forest stands bordering a mature forest of high conservation value. In each young stand we registered species occurrences on coarse dead wood in transects 0-50 m from the border between stand types. We quantified the effect of distance from the mature forest on the occurrence of forest-interior species in the young stands, while accounting for local environment and propagule sources. For comparison we also surveyed epixylic open-habitat (associated with open forests and generalist cryptogams. Species composition of epixylic cryptogams in young stands differed with distance from the mature forest: the frequency of occurrence of forest-interior species decreased with increasing distance whereas it increased for open-habitat species. Generalists were unaffected by distance. Epixylic, boreal forest-interior cryptogams do occur in matrix habitats such as clear-cuts. In addition, they are associated with the matrix edge because of a favourable microclimate closer to the mature forest on southern matrix edges. Retention and creation of dead wood in clear-cuts along the edges to focal habitats is a feasible way to enhance the long-term persistence of epixylic habitat specialists in fragmented landscapes. The proposed management measures should be performed in the whole stand as it matures, since microclimatic edge effects diminish as the matrix habitat matures. We argue that management that aims to increase

  10. Effects of Forest Fragmentation on Human Risk of Lyme Disease

    Science.gov (United States)

    Percent forest-herbaceous edge repeatedly explained most of the variability in reported Lyme disease rates within a rural-to-urban study gradient across central Maryland and southeastern Pennsylvania. A one-percent increase in forest-herbaceous edge was associated with an increas...

  11. Effects of climate change on Forest Service strategic goals

    Science.gov (United States)

    Forest Service U.S. Department of Agriculture

    2010-01-01

    Climate change affects forests and grasslands in many ways. Changes in temperature and precipitation affect plant productivity as well as some species' habitat. Changes in key climate variables affect the length of the fire season and the seasonality of National Forest hydrological regimes. Also, invasive species tend to adapt to climate change more easily and...

  12. Effectiveness of forest management strategies to mitigate effects of global change in Siberia

    Science.gov (United States)

    Eric Gustafson; Anatoly Shvidenko; Robert Scheller; Brian. Sturtevant

    2011-01-01

    Siberian forest ecosystems are experiencing multiple global changes. Climate change produces direct (temperature and precipitation) and indirect (altered fire regimes and increase in cold-limited insect outbreaks) effects. Although much of Siberia has not yet been subject to timber harvest, the frontier of timber cutting is advancing steadily across the region. We...

  13. Effect of an isolated semi-arid pine forest on the boundary layer height

    Science.gov (United States)

    Brugger, Peter; Banerjee, Tirtha; Kröniger, Konstantin; Preisler, Yakir; Rotenberg, Eyal; Tatarinov, Fedor; Yakir, Dan; Mauder, Matthias

    2017-04-01

    Forests play an important role for earth's climate by influencing the surface energy balance and CO2 concentrations in the atmosphere. Semi-arid forests and their effects on the local and regional climate are studied within the CliFF project (Climate Feedbacks and benefits of semi-arid Forests). This requires understanding of the atmospheric boundary layer over semi-arid forests, because it links the surface and the free atmosphere and determines the exchange of momentum, heat and trace gases. Our study site, Yatir, is a semi-arid isolated pine forest in the Negev desert in Israel. Higher roughness and lower albedo compared to the surrounding shrubland make it interesting to study the influences of the semi-arid Yatir forest on the boundary layer. Previous studies of the forest focused on the energy balance and secondary circulations. This study focuses on the boundary layer structure above the forest, in particular the boundary layer height. The boundary layer height is an essential parameter for many applications (e.g. construction of convective scaling parameters or air pollution modeling). We measured the boundary layer height upwind, over and downwind of the forest. In addition we measured at two sites wind profiles within the boundary layer and turbulent fluxes at the surface. This allows us to quantify the effects of the forest on boundary layer compared to the surrounding shrubland. Results show that the forest increases the boundary layer height in absence of a strong boundary layer top inversion. A model of the boundary layer height based on eddy-covariance data shows some agreement to the measurements, but fails during anticyclonic conditions and the transition to the nocturnal boundary layer. More complex models accounting for large scale influences are investigated. Further influences of the forest and surrounding shrubland on the turbulent transport of energy are discussed in a companion presentation (EGU2017-2219).

  14. Modelling long-term water yield effects of forest management in a Norway spruce forest

    Czech Academy of Sciences Publication Activity Database

    Yu, X.; Lamačová, A.; Duffy, Ch.; Krám, P.; Hruška, Jakub; White, T.; Bhatt, G.

    2015-01-01

    Roč. 60, č. 2 (2015), s. 174-191 ISSN 0262-6667 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073 Institutional support: RVO:67179843 Keywords : Lysina critical zone observatory * PIHM * Norway spruce * forest management Subject RIV: EH - Ecology, Behaviour Impact factor: 2.182, year: 2015

  15. The effect of trends in forest and ownership characteristics on recreational use of private forests

    Science.gov (United States)

    Donald F. Dennis

    1992-01-01

    Probit analysis was used to estimate correlations between recreational use of private woodland and forest, owner, and surrounding community characteristics. Land held by more highly educated owners or those reared in large cities was more likely to be used for recreation, while the opposite was true for land held by older owners.

  16. Current knowledge on effects of forest silvicultural operations on carbon sequestration in southern forests

    Science.gov (United States)

    John D. Cason; Donald L. Grebner; Andrew J. Londo; Stephen C. Grado

    2006-01-01

    Incentive programs to reduce carbon dioxide (CO2) emissions are increasing in number with the growing threat of global warming. Terrestrial sequestration of CO2 through forestry practices on newly established forests is a potential mitigation tool for developing carbon markets in the United States. The extent of industrial...

  17. Recession effects on the forests and forest products industries of the South.

    Science.gov (United States)

    Douglas Hodges; Andrew Hartsell; Consuelo Brandeis; Thomas Brandeis; James Bentley

    2012-01-01

    The economic recession affected southern forests and related industries substantially, particularly those sectors most closely related to home construction. Between 2005 and 2009, for example, the three primary forestry sectors – wood manufacturing, paper manufacturing, and forestry and logging – lost more than 110,000 jobs in the southern United States. This article...

  18. The integrated forest study on effects of atmospheric deposition; A status report

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D.W.; Lindberg, S.E.; Bondietti, E.A. (Oak Ridge National Lab., TN (USA)); Cole, D.W. (Washington Univ., Seattle, WA (USA)); Lovett, G.M. (Cary Aboretum, Millbrook, NY (US)); Mitchell, M. (State Univ. of New York, Syracuse, NY (USA)); Ragsdale, L.H. (Emory Univ., Atlanta, GA (USA))

    1987-01-01

    The principal objective of the Integrated Forest Study on Effects of Atmospheric Deposition is to determine the effects of atmospheric deposition at sulfur and nitrogen on forest nutrient cycling. The study integrates a field monitoring component, involving quantification of atmospheric deposition and nutrient cycling in a variety of forest sites, and experimental research, including laboratory and field studies to investigate selected atmospheric and soil processes in great detail. The research is being conducted at forested sites in the northwestern, northeastern, and southeastern United States and in Norway. The sites selected for this study represent a range of conditions in climate, air quality, soils, and vegetation, which will facilitate testing hypotheses about the effects of atmospheric sulfur and nitrogen deposition on forest nutrient cycles. Preliminary results show a wide range in atmospheric sulfur and nitrogen deposition and in ecosystem responses to such deposition, some of which are consistent with previous predictions.

  19. The effect of irradiation on demyelination induced by a virulent Semliki Forest virus

    International Nuclear Information System (INIS)

    Chew-Lim, M.; Webb, H.E.; Jagelma, S.

    1977-01-01

    A dose of 500 rad total body irradiation before Semliki Forest virus infection was the most effective in producing multiple foci of demyelination in Swiss mice. Animals receiving this dose had the highest virus titre of Semliki Forest virus persisting in the brain and a delayed antibody response. In spite of extensive demyelination no obvious clinical signs such as paralysis were observed. (author)

  20. Family Forest Owner Characteristics Shaped by Life Cycle, Cohort, and Period Effects

    Science.gov (United States)

    Sarah M. Butler; Brett J. Butler; Marla Markowski-Lindsay

    2017-01-01

    Understanding differences and similarities among family forest owners is important in the context of forest land conservation. This study assesses similarities and differences in landowners by analyzing life cycle effects, cohort differences, and period-specific events that shape people's attitudes and behaviors towards their forestland over time. Using data...

  1. Land use change effects on forest carbon cycling throughout the southern United States

    Science.gov (United States)

    Peter B. Woodbury; Linda S. Heath; James E. Smith

    2006-01-01

    We modeled the effects of afforestation and deforestation on carbon cycling in forest floor and soil from 1900 to 2050 throughout 13 states in the southern United States. The model uses historical data on gross (two-way) transitions between forest, pasture, plowed agriculture, and urban lands along with equations describing changes in carbon over many decades for each...

  2. The Effects of Cyclone Hudah on the Forest of Masoala Peninsula ...

    African Journals Online (AJOL)

    Cyclones regularly impact the east coast of Madagascar but almost nothing is known about their effects on Malagasy ecosystems. On 2 April 2000 the powerful winds of Cyclone Hudah struck the humid forests in the northern part of Masoala Peninsula. An analysis of satellite images revealed that 3 % of the forest here was ...

  3. Mechanisms of nitrogen deposition effects on temperate forest lichens and trees

    Science.gov (United States)

    Therese S. Carter; Christopher M. Clark; Mark E. Fenn; Sarah Jovan; Steven S. Perakis; Jennifer Riddell; Paul G. Schaberg; Tara L. Greaver; Meredith G. Hastings

    2017-01-01

    We review the mechanisms of deleterious nitrogen (N) deposition impacts on temperate forests, with a particular focus on trees and lichens. Elevated anthropogenic N deposition to forests has varied effects on individual organisms depending on characteristics both of the N inputs (form, timing, amount) and of the organisms (ecology, physiology) involved. Improved...

  4. Effects of biotic disturbances on forest carbon cycling in the United States and Canada

    Science.gov (United States)

    Jeffrey A. Hicke; Craig D. Allen; Ankur R. Desai; Michael C. Dietze; Ronald J. Hall; Edward H. Hogg; Daniel M. Kashian; David Moore; Kenneth F. Raffa; Rona N. Sturrock; James. Vogelmann

    2011-01-01

    Forest insects and pathogens are major disturbance agents that have affected millions of hectares in North America in recent decades, implying significant impacts to the carbon (C) cycle. Here, we review and synthesize published studies of the effects of biotic disturbances on forest C cycling in the United States and Canada. Primary productivity in stands was reduced...

  5. Effect of rock fragments on macropores and water effluent in a forest ...

    African Journals Online (AJOL)

    DR. NJ TONUKARI

    2012-05-15

    May 15, 2012 ... 2Key Laboratory of Forest Ecological Environment, Institute of Forest Ecology, Environment and Protection, Chinese. Academy of Forestry, Beijing 100091, China. Accepted 16 April, 2012. Rock fragments exert important effects on soil water movement and macropores.However,they are not well-studied in ...

  6. Effects of fertilization on phosphorus pools in the volcanic soil of a managed tropical forest

    Science.gov (United States)

    Dean F. Meason; Travis W. Idol; J.B. Friday; Paul G. Scowcroft

    2009-01-01

    Acacia koa forests benefit from phosphorus fertilisation, but it is unknown if fertilisation is a short or long term effect on P availability. Past research suggests that P cycling in soils with high P sorption capacity, such as Andisols, was through organic pathways. We studied leaf P and soil P fractions in a tropical forest Andisol for 3 years...

  7. Quantifying the effect of fuel reduction treatments on fire behavior in boreal forests

    Science.gov (United States)

    B.W. Butler; R.D. Ottmar; T.S. Rupp; R. Jandt; E. Miller; K. Howard; R. Schmoll; S. Theisen; R.E. Vihnanek; D. Jimenez

    2013-01-01

    Mechanical (e.g., shearblading) and manual (e.g., thinning) fuel treatments have become the preferred strategy of many fire managers and agencies for reducing fire hazard in boreal forests. This study attempts to characterize the effectiveness of four fuel treatments through direct measurement of fire intensity and forest floor consumption during a single prescribed...

  8. Effects of forest management on soil carbon: results of some long-term resampling studies

    Science.gov (United States)

    D.W. Johnson; Jennifer D. Knoepp; Wayne T. Swank; J. Shan; L.A. Morris; David H. D.H. van Lear; P.R. Kapeluck

    2002-01-01

    The effects of harvest intensity (sawlog, SAW; whole tree, WTH; and complete tree, CTH) on biomass and soil carbon (C) were studied in four forested sites in the Southeastern United States: (mixed deciduous forests at Oak Ridge, TN and Coweeta, NC; Pinus taeda at Clemson, SC; and P. eliottii at Bradford, FL). In general, harvesting had no lasting...

  9. Fire effects on Gambel oak in southwestern ponderosa pine-oak forests

    Science.gov (United States)

    Scott R. Abella; Peter Z. Fulé

    2008-01-01

    Gambel oak (Quercus gambelii) is ecologically and aesthetically valuable in southwestern ponderosa pine (Pinus ponderosa) forests. Fire effects on Gambel oak are important because fire may be used in pine-oak forests to manage oak directly or to accomplish other management objectives. We used published literature to: (1) ascertain...

  10. Human-driven topographic effects on the distribution of forest in a flat, lowland agricultural region

    DEFF Research Database (Denmark)

    Odgaard, Mette Vestergaard; Moeslund, Jesper Erenskjold; Dalgaard, Tommy

    2014-01-01

    Complex topography buffers forests against deforestation in mountainous regions. However, it is unknown if terrain also shapes forest distribution in lowlands where human impacts are likely to be less constrained by terrain. In such regions, if important at all, topographic effects will depend...

  11. Fuel treatment effects on tree-based forest carbon storage and emissions under modeled wildfire scenarios

    Science.gov (United States)

    M. Hurteau; M. North

    2009-01-01

    Forests are viewed as a potential sink for carbon (C) that might otherwise contribute to climate change. It is unclear, however, how to manage forests with frequent fire regimes to maximize C storage while reducing C emissions from prescribed burns or wildfire. We modeled the effects of eight different fuel treatments on treebased C storage and release over a century,...

  12. Effects of sevin-4-oil, dimilin, and orthene on forest birds in northeastern Oregon

    Science.gov (United States)

    Merle L. Richmond; Charles J. Henny; Randy L. Floyd; William R. Mannan; Deborah M. Finch; Lawrence R. DeWeese

    1979-01-01

    The possible harmful effect of insecticides on nontarget organisms should be a prominent concern in all attempts to control forest pests. Although all wildlife must be considered, birds are particularly vulnerable. The study reported here was part of the effort to find an environmentally safe method to control one of the major sources of insect damage to forest trees...

  13. Effects of forest management on streamflow, sediment yield, and erosion, Caspar Creek Experimental Watersheds

    Science.gov (United States)

    Elizabeth T. Keppeler; Jack Lewis; Thomas E. Lisle

    2003-01-01

    Abstract - Caspar Creek Experimental Watersheds were established in 1962 to research the effects of forest management on streamflow, sedimentation, and erosion in the rainfall-dominated, forested watersheds of north coastal California. Currently, 21 stream sites are gaged in the North Fork (473 ha) and South Fork (424 ha) of Caspar Creek. From 1971 to 1973, 65% of...

  14. Wildfire and fuel treatment effects on forest carbon dynamics in the western United States

    Science.gov (United States)

    Joseph C. Restiano; David L. Peterson

    2013-01-01

    Sequestration of carbon (C) in forests has the potential to mitigate the effects of climate change by offsetting future emissions of greenhouse gases. However, in dry temperate forests, wildfire is a natural disturbance agent with the potential to release large fluxes of C into the atmosphere. Climate-driven increases in wildfire extent and severity arc expected to...

  15. Response to Comment on "persistent effects of pre-Columbian plant domestication on Amazonian forest composition"

    NARCIS (Netherlands)

    Braga Junqueira, Andre; Levis, Carolina; Bongers, Frans; Peña-Claros, Marielos; Clement, Charles Roland; Costa, Flávia R.C.; Steege, Hans Ter

    2017-01-01

    McMichael et al. state that we overlooked the effects of post-Columbian human activities in shaping current floristic patterns in Amazonian forests. We formally show that post- Columbian human influences on Amazonian forests are indeed important, but they have played a smaller role when compared

  16. Micellar effect on metal-ligand complexes of Co(II), Ni(II), Cu(II) and ...

    African Journals Online (AJOL)

    Chemical speciation of citric acid complexes of Co(II), Ni(II), Cu(II) and Zn(II) was investigated pH-metrically in 0.0-2.5% anionic, cationic and neutral micellar media. The primary alkalimetric data were pruned with SCPHD program. The existence of different binary species was established from modeling studies using the ...

  17. Anomalous Nernst effect in type-II Weyl semimetals

    Science.gov (United States)

    Saha, Subhodip; Tewari, Sumanta

    2018-01-01

    Topological Weyl semimetals (WSM), a new state of quantum matter with gapless nodal bulk spectrum and open Fermi arc surface states, have recently sparked enormous interest in condensed matter physics. Based on the symmetry and fermiology, it has been proposed that WSMs can be broadly classified into two types, type-I and type-II Weyl semimetals. While the undoped, conventional, type-I WSMs have point like Fermi surface and vanishing density of states (DOS) at the Fermi energy, the type-II Weyl semimetals break Lorentz symmetry explicitly and have tilted conical spectra with electron and hole pockets producing finite DOS at the Fermi level. The tilted conical spectrum and finite DOS at Fermi level in type-II WSMs have recently been shown to produce interesting effects such as a chiral anomaly induced longitudinal magnetoresistance that is strongly anisotropic in direction and a novel anomalous Hall effect. In this work, we consider the anomalous Nernst effect in type-II WSMs in the absence of an external magnetic field using the framework of semi-classical Boltzmann theory. Based on both a linearized model of time-reversal breaking WSM with a higher energy cut-off and a more realistic lattice model, we show that the anomalous Nernst response in these systems is strongly anisotropic in space, and can serve as a reliable signature of type-II Weyl semimetals in a host of magnetic systems with spontaneously broken time reversal symmetry.

  18. Separating the effects of forest type and elevation on the diversity of litter invertebrate communities in a humid tropical forest in Puerto Rico.

    Science.gov (United States)

    BARBARA A. RICHARDSON; MICHAEL J. RICHARDSON; FELIPE N. SOTO-ADAMES

    2005-01-01

    1. The primary effects of climatic conditions on invertebrate litter communities, and the secondary effects of different forest types, were distinguished by using the sierra palm as a control in a natural experiment along an elevational gradient in the Luquillo Mountains. These mountains have three well-defined forest types along the gradient, with the palm occurring...

  19. Edge effects on understory epiphytic ferns and epiphyllous bryophytes in moist afromontane forests of Ethiopia

    Directory of Open Access Journals (Sweden)

    Hylander Kristoffer

    2013-12-01

    Full Text Available Most studies on edge effects in tropical forests have been conducted in landscapes with low human population density and in situations where the edges have been left unused after logging of the adjacent area. Here we studied forest margins heavily used by local farmers in a forest/agriculture mosaic landscape in Ethiopia. We compared forest structure and plant species composition across 41 forest-agriculture ecotones from 200 m out into the agricultural area to 200 m into the forest. There are strong edge effects from the edge and into the forest on canopy cover and number of stumps and apparently these forest-agricultural edges are intensively used by humans. They are penetrated by paths, beehives are found in the trees, timber of various dimensions is harvested and there is sometimes substantial cover of perennial wild (or semi-wild crops such as coffee and spices. The number of understory epiphytic fern species as well as number of epiphyllous (i.e., growing on leaves bryophyte species was lower at 20 m than at 75 m from the edge. The number of fern species was higher in newly created edges and thereafter they declined, which indicates an extinction debt. This pattern was not seen for the epiphyllous bryophytes. It is likely that different human management activities are responsible for many of the found edge effects besides wind and sun effects from the edge. Tropical forest margins provide important resources for people in many landscapes. It is important to understand how such use affects the biota of the forests. This study shows that there are substantial edge effects, but that the edge effects do not seem to become worse over time for epiphyllous bryophytes and only slightly so for ferns.

  20. Ionizing radiation effect on enzymes. II

    International Nuclear Information System (INIS)

    Libicky, A.; Fidlerova, J.; Urban, J.; Chottova, O.; Kubankova, V.

    1980-01-01

    The effects of gamma radiation on the efficacy of chymotrypsin in pancreatin prepared by the separation of enzymes from an activated pancreas extract, in the same sample in which the content of lipids was increased to 16.55%, and in pancreatin prepared by drying an incompletely activated ground pancreas were compared with the effect of radiation on crystaline lyophilized chymotrypsin. The working conditions were identical with those described in the previous communication, all samples possessed nearly identical humidity on irradiation. The efficacy of chymotrypsin was determined by the method of PhBs 3, ethyl ester L-tyrosine hydrochloride being used as the substrate. The results were statistically evaluated and after calculation for dried lipid-free substance represented in graphs. The sequence of the loss of efficacy in pancreatin corresponded to the sequence of the loss of the total proteolytic efficacy found in the previous communication. The lowest remaining efficacy was found in crystalline lyophilized chymotrypsin. Percent losses of chymotrypsin efficacy in pancreatin determined by the synthetic substrate were in good agreement with the loss of the total proteolytic efficacy of the same samples determined by casein. (author)

  1. Combating the effects of climatic change on forests by mitigation strategies

    Directory of Open Access Journals (Sweden)

    Dieter Matthias

    2010-11-01

    Full Text Available Abstract Background Forests occur across diverse biomes, each of which shows a specific composition of plant communities associated with the particular climate regimes. Predicted future climate change will have impacts on the vulnerability and productivity of forests; in some regions higher temperatures will extend the growing season and thus improve forest productivity, while changed annual precipitation patterns may show disadvantageous effects in areas, where water availability is restricted. While adaptation of forests to predicted future climate scenarios has been intensively studied, less attention was paid to mitigation strategies such as the introduction of tree species well adapted to changing environmental conditions. Results We simulated the development of managed forest ecosystems in Germany for the time period between 2000 and 2100 under different forest management regimes and climate change scenarios. The management regimes reflect different rotation periods, harvesting intensities and species selection for reforestations. The climate change scenarios were taken from the IPCC's Special Report on Emission Scenarios (SRES. We used the scenarios A1B (rapid and successful economic development and B1 (high level of environmental and social consciousness combined with a globally coherent approach to a more sustainable development. Our results indicate that the effects of different climate change scenarios on the future productivity and species composition of German forests are minor compared to the effects of forest management. Conclusions The inherent natural adaptive capacity of forest ecosystems to changing environmental conditions is limited by the long life time of trees. Planting of adapted species and forest management will reduce the impact of predicted future climate change on forests.

  2. Forest transitions in Eastern Europe and their effects on carbon budgets.

    Science.gov (United States)

    Kuemmerle, Tobias; Kaplan, Jed O; Prishchepov, Alexander V; Rylsky, Ilya; Chaskovskyy, Oleh; Tikunov, Vladimir S; Müller, Daniel

    2015-08-01

    Forests often rebound from deforestation following industrialization and urbanization, but for many regions our understanding of where and when forest transitions happened, and how they affected carbon budgets remains poor. One such region is Eastern Europe, where political and socio-economic conditions changed drastically over the last three centuries, but forest trends have not yet been analyzed in detail. We present a new assessment of historical forest change in the European part of the former Soviet Union and the legacies of these changes on contemporary carbon stocks. To reconstruct forest area, we homogenized statistics at the provincial level for ad 1700-2010 to identify forest transition years and forest trends. We contrast our reconstruction with the KK11 and HYDE 3.1 land change scenarios, and use all three datasets to drive the LPJ dynamic global vegetation model to calculate carbon stock dynamics. Our results revealed that forest transitions in Eastern Europe occurred predominantly in the early 20th century, substantially later than in Western Europe. We also found marked geographic variation in forest transitions, with some areas characterized by relatively stable or continuously declining forest area. Our data suggest extensive deforestation in European Russia already prior to ad 1700, and even greater deforestation in the 18th and 19th centuries than in the KK11 and HYDE scenarios. Based on our reconstruction, cumulative carbon emissions from deforestation were greater before 1700 (60 Pg C) than thereafter (29 Pg C). Summed over our entire study area, forest transitions led to a modest uptake in carbon over recent decades, with our dataset showing the smallest effect (<5.5 Pg C) and a more heterogeneous pattern of source and sink regions. This suggests substantial sequestration potential in regrowing forests of the region, a trend that may be amplified through ongoing land abandonment, climate change, and CO2 fertilization. © 2015 John Wiley & Sons

  3. Forest stand structure, productivity, and age mediate climatic effects on aspen decline

    Science.gov (United States)

    Bell, David M.; Bradford, John B.; Lauenroth, William K.

    2014-01-01

    Because forest stand structure, age, and productivity can mediate the impacts of climate on quaking aspen (Populus tremuloides) mortality, ignoring stand-scale factors limits inference on the drivers of recent sudden aspen decline. Using the proportion of aspen trees that were dead as an index of recent mortality at 841 forest inventory plots, we examined the relationship of this mortality index to forest structure and climate in the Rocky Mountains and Intermountain Western United States. We found that forest structure explained most of the patterns in mortality indices, but that variation in growing-season vapor pressure deficit and winter precipitation over the last 20 years was important. Mortality index sensitivity to precipitation was highest in forests where aspen exhibited high densities, relative basal areas, quadratic mean diameters, and productivities, whereas sensitivity to vapor pressure deficit was highest in young forest stands. These results indicate that the effects of drought on mortality may be mediated by forest stand development, competition with encroaching conifers, and physiological vulnerabilities of large trees to drought. By examining mortality index responses to both forest structure and climate, we show that forest succession cannot be ignored in studies attempting to understand the causes and consequences of sudden aspen decline.

  4. The Prefrontal Cortex Activity and Psychological Effects of Viewing Forest Landscapes in Autumn Season.

    Science.gov (United States)

    Joung, Dawou; Kim, Geonwoo; Choi, Yoonho; Lim, HyoJin; Park, Soonjoo; Woo, Jong-Min; Park, Bum-Jin

    2015-06-26

    Recently reported research indicate that forest environments have physiological and psychological relaxing effects compared to urban environments. However, some researchers claim that the stress of the subjects from being watched by others during measurements can affect the measurement result in urban experiments conducted in the center of a street. The present study was conducted to determine whether forest environments have physiological and psychological relaxing effects, using comparison of viewing a forest area with viewing an urban area from the roof of an urban building without being watched by others. Near-infrared spectroscopy (NIRS) measurement was performed on subjects while they viewed scenery for 15 min at each experimental site (urban and forest areas). Subjective assessments were performed after the NIRS measurement was complete. Total hemoglobin and oxyhemoglobin concentrations were significantly lower in the forest area than in the urban area. For semantic differential in subjective assessments, feelings of "comfortable", "natural", and "soothed" were significantly higher in the forest area than in the urban area, and for profile of mood states, negative emotions were significantly lower in the forest area than in the urban area. The results of physiological and psychological measurements show that viewing the forest enabled effective relaxation.

  5. Management Effectiveness of a Secondary Coniferous Forest for Landscape Appreciation and Psychological Restoration.

    Science.gov (United States)

    Takayama, Norimasa; Fujiwara, Akio; Saito, Haruo; Horiuchi, Masahiro

    2017-07-18

    We investigated the influence of forest management on landscape appreciation and psychological restoration in on-site settings by exposing respondents to an unmanaged, dense coniferous (crowding) forest and a managed (thinned) coniferous forest; we set the two experimental settings in the forests of the Fuji Iyashinomoroi Woodland Study Center. The respondents were individually exposed to both settings while sitting for 15 min and were required to answer three questionnaires to analyze the psychological restorative effects before and after the experiment (feeling (the Profile of Mood States), affect (the Positive and Negative Affect Schedule), and subjective restorativeness (the Restorative Outcome Scale). To compare landscape appreciation, they were required to answer another two questionnaires only after the experiment, for scene appreciation (the semantic differential scale) and for the restorative properties of each environment (the Perceived Restorativeness Scale). Finally, we obtained these findings: (1) the respondents evaluated each forest environment highly differently and evaluated the thinned forest setting more positively; (2) the respondents' impressions of the two physical environments did not appear to be accurately reflected in their evaluations; (3) forest environments have potential restorative effects whether or not they are managed, but these effects can be partially enhanced by managing the forests.

  6. The Prefrontal Cortex Activity and Psychological Effects of Viewing Forest Landscapes in Autumn Season

    Directory of Open Access Journals (Sweden)

    Dawou Joung

    2015-06-01

    Full Text Available Recently reported research indicate that forest environments have physiological and psychological relaxing effects compared to urban environments. However, some researchers claim that the stress of the subjects from being watched by others during measurements can affect the measurement result in urban experiments conducted in the center of a street. The present study was conducted to determine whether forest environments have physiological and psychological relaxing effects, using comparison of viewing a forest area with viewing an urban area from the roof of an urban building without being watched by others. Near-infrared spectroscopy (NIRS measurement was performed on subjects while they viewed scenery for 15 min at each experimental site (urban and forest areas. Subjective assessments were performed after the NIRS measurement was complete. Total hemoglobin and oxyhemoglobin concentrations were significantly lower in the forest area than in the urban area. For semantic differential in subjective assessments, feelings of “comfortable”, “natural”, and “soothed” were significantly higher in the forest area than in the urban area, and for profile of mood states, negative emotions were significantly lower in the forest area than in the urban area. The results of physiological and psychological measurements show that viewing the forest enabled effective relaxation.

  7. Interactive effects of environmental change and management strategies on regional forest carbon emissions.

    Science.gov (United States)

    Hudiburg, Tara W; Luyssaert, Sebastiaan; Thornton, Peter E; Law, Beverly E

    2013-11-19

    Climate mitigation activities in forests need to be quantified in terms of the long-term effects on forest carbon stocks, accumulation, and emissions. The impacts of future environmental change and bioenergy harvests on regional forest carbon storage have not been quantified. We conducted a comprehensive modeling study and life-cycle assessment of the impacts of projected changes in climate, CO2 concentration, and N deposition, and region-wide forest management policies on regional forest carbon fluxes. By 2100, if current management strategies continue, then the warming and CO2 fertilization effect in the given projections result in a 32-68% increase in net carbon uptake, overshadowing increased carbon emissions from projected increases in fire activity and other forest disturbance factors. To test the response to new harvesting strategies, repeated thinnings were applied in areas susceptible to fire to reduce mortality, and two clear-cut rotations were applied in productive forests to provide biomass for wood products and bioenergy. The management strategies examined here lead to long-term increased carbon emissions over current harvesting practices, although semiarid regions contribute little to the increase. The harvest rates were unsustainable. This comprehensive approach could serve as a foundation for regional place-based assessments of management effects on future carbon sequestration by forests in other locations.

  8. The cumulative effects of forest disturbance and climate variability on streamflow components in a large forest-dominated watershed

    Science.gov (United States)

    Li, Qiang; Wei, Xiaohua; Zhang, Mingfang; Liu, Wenfei; Giles-Hansen, Krysta; Wang, Yi

    2018-02-01

    Assessing how forest disturbance and climate variability affect streamflow components is critical for watershed management, ecosystem protection, and engineering design. Previous studies have mainly evaluated the effects of forest disturbance on total streamflow, rarely with attention given to its components (e.g., base flow and surface runoff), particularly in large watersheds (>1000 km2). In this study, the Upper Similkameen River watershed (1810 km2), an international watershed situated between Canada and the USA, was selected to examine how forest disturbance and climate variability interactively affect total streamflow, baseflow, and surface runoff. Baseflow was separated using a combination of the recursive digital filter method and conductivity mass balance method. Time series analysis and modified double mass curves were then employed to quantitatively separate the relative contributions of forest disturbance and climate variability to each streamflow component. Our results showed that average annual baseflow and baseflow index (baseflow/streamflow) were 113.3 ± 35.6 mm year-1 and 0.27 for 1954-2013, respectively. Forest disturbance increased annual streamflow, baseflow, and surface runoff of 27.7 ± 13.7 mm, 7.4 ± 3.6 mm, and 18.4 ± 12.9 mm, respectively, with its relative contributions to the changes in respective streamflow components being 27.0 ± 23.0%, 29.2 ± 23.1%, and 25.7 ± 23.4%, respectively. In contrast, climate variability decreased them by 74.9 ± 13.7 mm, 17.9 ± 3.6 mm, and 53.3 ± 12.9 mm, respectively, with its relative contributions to the changes in respective streamflow components being 73.0 ± 23.0%, 70.8 ± 23.1% and 73.1 ± 23.4%, respectively. Despite working in opposite ways, the impacts of climate variability on annual streamflow, baseflow, and surface runoff were of a much greater magnitude than forest disturbance impacts. This study has important implications for the protection of aquatic habitat, engineering design, and

  9. Integrated effects of air pollution and climate change on forests: A northern hemisphere perspective

    International Nuclear Information System (INIS)

    Bytnerowicz, Andrzej; Omasa, Kenji; Paoletti, Elena

    2007-01-01

    Many air pollutants and greenhouse gases have common sources, contribute to radiative balance, interact in the atmosphere, and affect ecosystems. The impacts on forest ecosystems have been traditionally treated separately for air pollution and climate change. However, the combined effects may significantly differ from a sum of separate effects. We review the links between air pollution and climate change and their interactive effects on northern hemisphere forests. A simultaneous addressing of the air pollution and climate change effects on forests may result in more effective research, management and monitoring as well as better integration of local, national and global environmental policies. - Simultaneous addressing air pollution and climate change effects on forests is an opportunity for capturing synergies in future research and monitoring

  10. Assessing urban forest effects and values, Washington, D.C.'s urban forest

    Science.gov (United States)

    David J. Nowak; Robert E. III Hoehn; Daniel E. Crane; Jack C. Stevens; Jeffrey T. Walton

    2006-01-01

    An analysis of trees in Washington, D.C. reveals that this city has about 1,928,000 trees with canopies that cover 28.6 percent of the area. The most common tree species are American beech, red maple, and boxelder. The urban forest currently store about 526,000 tons of carbon valued at $9.7 million. In addition, these trees remove about 16,200 tons of carbon per year...

  11. Assessing urban forest effects and values, New York City's urban forest

    Science.gov (United States)

    David J. Nowak; Robert E., III Hoehn; Daniel E. Crane; Jack C. Stevens; Jeffrey T. Walton

    2007-01-01

    An analysis of trees in New York City reveals that this city has about 5.2 million trees with canopies that cover 20.9 percent of the area. The most common tree species are tree of heaven, black cherry, and sweetgum. The urban forest currently stores about 1.35 million tons of carbon valued at $24.9 million. In addition, these trees remove about 42,300 tons of carbon...

  12. SIMFERT: Its Use for Teaching the Effects of Forest Fertilization.

    Science.gov (United States)

    Johnson, James E.; Allen, H. Lee

    1989-01-01

    Summarizes the capabilities of a computer program related to forest fertilization. Provides a description of input parameters, some sample exercises, software specifications, and availability information. Additional references are listed. (Author/RT)

  13. Analysis Of Income Effects Of Forest Products Activities Among ...

    African Journals Online (AJOL)

    Saharan Africa including Nigeria especially in Enugu state depend on forest resources to meet a variety of livelihood objectives including food security, social security, income and employment generation, risk management and essential subsistence ...

  14. Effects of Forest Gaps on Litter Lignin and Cellulose Dynamics Vary Seasonally in an Alpine Forest

    Directory of Open Access Journals (Sweden)

    Han Li

    2016-01-01

    Full Text Available To understand how forest gaps and the associated canopy control litter lignin and cellulose dynamics by redistributing the winter snow coverage and hydrothermal conditions in the growing season, a field litterbag trial was conducted in the alpine Minjiang fir (Abies faxoniana Rehder and E.H. Wilson forest in a transitional area located in the upper reaches of the Yangtze River and the eastern Tibetan Plateau. Over the first year of litter decomposition, the litter exhibited absolute cellulose loss and absolute lignin accumulation except for the red birch litter. The changes in litter cellulose and lignin were significantly affected by the interactions among gap position, period and species. Litter cellulose exhibited a greater loss in the winter with the highest daily loss rate observed during the snow cover period. Both cellulose and lignin exhibited greater changes under the deep snow cover at the gap center in the winter, but the opposite pattern occurred under the closed canopy in the growing season. The results suggest that decreased snowpack seasonality due to winter warming may limit litter cellulose and lignin degradation in alpine forest ecosystems, which could further inhibit litter decomposition. As a result, the ongoing winter warming and gap vanishing would slow soil carbon sequestration from foliar litter in cold biomes.

  15. Critical appraisal: dental amalgam update--part II: biological effects.

    Science.gov (United States)

    Wahl, Michael J; Swift, Edward J

    2013-12-01

    Dental amalgam restorations have been controversial for over 150 years. In Part I of this Critical Appraisal, the clinical efficacy of dental amalgam was updated. Here in Part II, the biological effects of dental amalgam are addressed. © 2013 The Authors.Journal of Esthetic and Restorative Dentistry © 2013 Wiley Periodicals, Inc.

  16. Forest Management Effects on Surface Soil Carbon and Nitrogen

    Science.gov (United States)

    Jennifer D. Knoepp; Wayne T. Swank

    1997-01-01

    Changes in surface soil C and N can result from forest management practices and may provide an index of impacts on long-term site productivity. Soil C and N were measured over time for five water- sheds in the southern Appalachians: two aggrading hardwood forests, one south- and one north-facing, undisturbed since the 1920s;a white pine (PinussfrobusL.) plantation...

  17. Physiological and Psychological Effects of a Forest Therapy Program on Middle-Aged Females

    Directory of Open Access Journals (Sweden)

    Hiroko Ochiai

    2015-12-01

    Full Text Available The natural environment is increasingly recognized as an effective counter to urban stress, and “Forest Therapy” has recently attracted attention as a relaxation and stress management activity with demonstrated clinical efficacy. The present study assessed the physiological and psychological effects of a forest therapy program on middle-aged females. Seventeen Japanese females (62.2 ± 9.4 years; mean ± standard deviation participated in this experiment. Pulse rate, salivary cortisol level, and psychological indices were measured on the day before forest therapy and on the forest therapy day. Pulse rate and salivary cortisol were significantly lower than baseline following forest therapy, indicating that subjects were in a physiologically relaxed state. Subjects reported feeling significantly more “comfortable,” “relaxed,” and “natural” according to the semantic differential (SD method. The Profile of Mood State (POMS negative mood subscale score for “tension–anxiety” was significantly lower, while that for “vigor” was significantly higher following forest therapy. Our study revealed that forest therapy elicited a significant (1 decrease in pulse rate, (2 decrease in salivary cortisol levels, (3 increase in positive feelings, and (4 decrease in negative feelings. In conclusion, there are substantial physiological and psychological benefits of forest therapy on middle-aged females.

  18. Physiological and Psychological Effects of a Forest Therapy Program on Middle-Aged Females.

    Science.gov (United States)

    Ochiai, Hiroko; Ikei, Harumi; Song, Chorong; Kobayashi, Maiko; Miura, Takashi; Kagawa, Takahide; Li, Qing; Kumeda, Shigeyoshi; Imai, Michiko; Miyazaki, Yoshifumi

    2015-12-01

    The natural environment is increasingly recognized as an effective counter to urban stress, and "Forest Therapy" has recently attracted attention as a relaxation and stress management activity with demonstrated clinical efficacy. The present study assessed the physiological and psychological effects of a forest therapy program on middle-aged females. Seventeen Japanese females (62.2 ± 9.4 years; mean ± standard deviation) participated in this experiment. Pulse rate, salivary cortisol level, and psychological indices were measured on the day before forest therapy and on the forest therapy day. Pulse rate and salivary cortisol were significantly lower than baseline following forest therapy, indicating that subjects were in a physiologically relaxed state. Subjects reported feeling significantly more "comfortable," "relaxed," and "natural" according to the semantic differential (SD) method. The Profile of Mood State (POMS) negative mood subscale score for "tension-anxiety" was significantly lower, while that for "vigor" was significantly higher following forest therapy. Our study revealed that forest therapy elicited a significant (1) decrease in pulse rate, (2) decrease in salivary cortisol levels, (3) increase in positive feelings, and (4) decrease in negative feelings. In conclusion, there are substantial physiological and psychological benefits of forest therapy on middle-aged females.

  19. Anthropogenic effects on a tropical forest according to the distance from human settlements.

    Science.gov (United States)

    Popradit, Ananya; Srisatit, Thares; Kiratiprayoon, Somboon; Yoshimura, Jin; Ishida, Atsushi; Shiyomi, Masae; Murayama, Takehiko; Chantaranothai, Pranom; Outtaranakorn, Somkid; Phromma, Issara

    2015-10-05

    The protection of tropical forests is one of the most urgent issues in conservation biology because of the rapid deforestation that has occurred over the last 50 years. Even in protected forests, the anthropogenic effects from newly expanding villages such as harvesting of medicinal plants, pasturing cattle and forest fires can induce environmental modifications, especially on the forest floor. We evaluated the anthropogenic effects of the daily activities of neighboring residents on natural forests in 12 plots extending from the village boundary into a natural forest in Thailand. The basal area per unit land area did not present a significant trend; however, the species diversity of woody plants decreased linearly towards the village boundary, which caused a loss of individual density because of severe declines in small saplings compared with adult trees and large saplings in proximity to the village. An analysis of tree-size categories indicates a lack of small samplings near the village boundary. The current forest appears to be well protected based on the adult tree canopy, but regeneration of the present-day forests is unlikely because of the loss of seedlings.

  20. Anthropogenic effects on a tropical forest according to the distance from human settlements

    Science.gov (United States)

    Popradit, Ananya; Srisatit, Thares; Kiratiprayoon, Somboon; Yoshimura, Jin; Ishida, Atsushi; Shiyomi, Masae; Murayama, Takehiko; Chantaranothai, Pranom; Outtaranakorn, Somkid; Phromma, Issara

    2015-10-01

    The protection of tropical forests is one of the most urgent issues in conservation biology because of the rapid deforestation that has occurred over the last 50 years. Even in protected forests, the anthropogenic effects from newly expanding villages such as harvesting of medicinal plants, pasturing cattle and forest fires can induce environmental modifications, especially on the forest floor. We evaluated the anthropogenic effects of the daily activities of neighboring residents on natural forests in 12 plots extending from the village boundary into a natural forest in Thailand. The basal area per unit land area did not present a significant trend; however, the species diversity of woody plants decreased linearly towards the village boundary, which caused a loss of individual density because of severe declines in small saplings compared with adult trees and large saplings in proximity to the village. An analysis of tree-size categories indicates a lack of small samplings near the village boundary. The current forest appears to be well protected based on the adult tree canopy, but regeneration of the present-day forests is unlikely because of the loss of seedlings.

  1. Hydrological effects on carbon cycles of Canada's forests and wetlands

    International Nuclear Information System (INIS)

    Ju, Weimin; Chen, Jing M.; Black, T. Andrew; Barr, Alan G.; Mccaughey, Harry; Roulet, Nigel T.

    2006-01-01

    The hydrological cycle has significant effects on the terrestrial carbon (C) balance through its controls on photosynthesis and C decomposition. A detailed representation of the water cycle in terrestrial C cycle models is essential for reliable estimates of C budgets. However, it is challenging to accurately describe the spatial and temporal variations of soil water, especially for regional and global applications. Vertical and horizontal movements of soil water should be included. To constrain the hydrology-related uncertainty in modelling the regional C balance, a three-dimensional hydrological module was incorporated into the Integrated Terrestrial Ecosystem Carbon-budget model (InTEC V3.0). We also added an explicit parameterization of wetlands. The inclusion of the hydrological module considerably improved the model's ability to simulate C content and balances in different ecosystems. Compared with measurements at five flux-tower sites, the model captured 85% and 82% of the variations in volumetric soil moisture content in the 0-10 cm and 10-30 cm depths during the growing season and 84% of the interannual variability in the measured C balance. The simulations showed that lateral subsurface water redistribution is a necessary mechanism for simulating water table depth for both poorly drained forest and peatland sites. Nationally, soil C content and their spatial variability are significantly related to drainage class. Poorly drained areas are important C sinks at the regional scale, however, their soil C content and balances are difficult to model and may have been inadequately represented in previous C cycle models. The InTEC V3.0 model predicted an annual net C uptake by Canada's forests and wetlands for the period 1901-1998 of 111.9 Tg C/yr, which is 41.4 Tg C/yr larger than our previous estimate (InTEC V2.0). The increase in the net C uptake occurred mainly in poorly drained regions and resulted from the inclusion of a separate wetland parameterization

  2. Effective radium concentration in agricultural versus forest topsoils.

    Science.gov (United States)

    Perrier, Frédéric; Girault, Frédéric; Bouquerel, Hélène; Bollinger, Laurent

    2016-08-01

    Effective radium-226 activity concentration (ECRa), the radon-222 source term, was measured in the laboratory with 724 topsoil samples collected over a ∼110 km(2) area located ∼20 km south of Paris, France. More than 2100 radon accumulation experiments were performed, with radon concentration measured using scintillation flasks, leading to relative uncertainties on ECRa varying from 10% for ECRa = 2 Bq⋅kg(-1) to less than 6% for ECRa > 5 Bq⋅kg(-1). Small-scale dispersion, studied at one location with 12 samples, and systematically at 100 locations with three topsoils separated by 1 m, was of the order of 7%, demonstrating that a single soil sample is reasonably representative. Agricultural topsoils (n = 540) had an average (arithmetic) ECRa of 8.09 ± 0.11 Bq⋅kg(-1), and a range from 2.80 ± 0.22 to 19.5 ± 1.1 Bq⋅kg(-1), while forest topsoils (n = 184), with an average of 3.21 ± 0.14 Bq⋅kg(-1) and a range from 0.45 ± 0.12 to 9.09 ± 0.55 Bq⋅kg(-1), showed a clear systematic reduction of ECRa when compared with the closest agricultural soil sample. Large-scale organization of ECRa was impressive for agricultural topsoils, with homogeneous domains of several kilometers size, characterized by smooth variations smaller than 10%. These patches emerged despite heavy human remodeling; they are controlled by the main geographical units, but do not necessarily coincide with them. Valleys were characterized by larger dispersion and less organization. This study illustrates how biosphere and anthroposphere modify the soil distribution inherited from geological processes, an important baseline needed for the study of contaminated sites. Furthermore, the observed depletion of forest topsoils suggests an atmospheric radon signature of deforestation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Modeling of pheromone communication system of forest Lepidopterous insects. II. Model of female searching by male

    Directory of Open Access Journals (Sweden)

    A. V. Kovalev

    2015-06-01

    Full Text Available We propose an agent­based simulation model search. This model allows us to evaluate the effectiveness of different males­females pheromone search strategies for Lepidoptera. In the model, we consider the simplest case of the search, when the pheromone has only one chemical component. It is assumed that the insects are able to detect the pheromone molecules and the sensory cells generate action potentials in contact with the pheromone for some time. Thereafter pheromone molecule is inactivated. This behavior can be regarded as a memory of individual. Proportion of individuals who have reached the source is selected as an integral indicator of the search efficiency. To evaluate the effectiveness, numeric experiments were performed in different conditions: random walk, search algorithm without memory, and algorithm with memory and return mechanism. The resulting effectiveness of source localization by insects for flight in turbulent flows is ~ 70 %, which corresponds to experiments with live specimens in literature. In this case, proposed pheromone search algorithm is quite simple, which makes it biologically correct. Conducted modeling calculations can be the starting point for planning of field observations and pest monitoring systems using pheromone traps.

  4. Effect of industrial pollution on behaviour of radionuclides in forest ecosystems

    International Nuclear Information System (INIS)

    Outola, I.

    2009-01-01

    To investigate how and to what extent industrial pollution affects the behaviour of radionuclides in forest ecosystems, studies were conducted in the vicinity of two Cu-Ni smelters: one in a pine forest at Harjavalta, Finland, and the other in a spruce forest at Monchegorsk, Russia. Industrial pollution had significant effects on the distribution of radionuclides in soil horizons. With the increase in pollution towards the smelter, radionuclides were accumulated more in the litter layer because the conversion of litter into organic material was diminished due to inhibited microbial activity. As a result, the organic layer contained less radionuclides towards the smelter. The effect of industrial pollution on soil-to-plant transfer was complex. The effect varied with radionuclide, plant species and also on forest type. For 137 Cs, soil-to-plant transfer decreased significantly as industrial pollution increased in pine forest, whereas the decrease was less pronounced in spruce forest. Root uptake of 239,240 Pu by plants is extremely small, and plant contamination by resuspended soil is an important factor in considering the soil-to-plant transfer of this radionuclide. In spruce forest, more plutonium was transferred into plants when pollution load increased due to resuspension of litter particles, which contained higher concentrations of plutonium in the vicinity of the smelter. Soil-to-plant transfer of plutonium was much less affected in pine forests contaminated with industrial pollution. This research clearly indicates the sensitivity of the northern forest ecosystem to inorganic pollutants. Prediction of the soil-to-plant transfer of radionuclides in industrially polluted forest ecosystems requires detailed information on the total deposition, vertical distribution of radionuclides in soil, soil microbiological factors, other soil parameters as well as the rooting depths of the plants. (LN)

  5. Forest report 2016; Waldzustandsbericht 2016

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2016-07-01

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

  6. Effects of Walking in Bamboo Forest and City Environments on Brainwave Activity in Young Adults

    Directory of Open Access Journals (Sweden)

    Ahmad Hassan

    2018-01-01

    Full Text Available Background. In Japan, “Shinrin-yoku” or forest bathing (spending time in forests is a major practice used for relaxation. However, its effects on promoting human mental health are still under consideration. The objective of this study was to investigate the physiological and psychological relaxation effects of forest walking on adults. Sixty participants (50% males; 50% females were trained to walk 15-minute predetermined courses in a bamboo forest and a city area (control. The length of the courses was the same to allow comparison of the effects of both environments. Blood pressure and EEG results were measured to assess the physiological responses and the semantic differential method (SDM and STAI were used to study the psychological responses. Blood pressure was significantly decreased and variation in brain activity was observed in both environments. The results of the two questionnaires indicated that walking in the bamboo forest improves mood and reduces anxiety. Moreover, the mean meditation and attention scores were significantly increased after walking in a bamboo forest. The results of the physiological and psychological measurements indicate the relaxing effects of walking in a bamboo forest on adults.

  7. Simulating fuel treatment effects in dry forests of the western United States: testing the principles of a fire-safe forest

    Science.gov (United States)

    Morris C. Johnson; Maureen C Kennedy; David L. Peterson

    2011-01-01

    We used the Fire and Fuels Extension to the Forest Vegetation Simulator (FFE-FVS) to simulate fuel treatment effects on stands in low- to midelevation dry forests (e.g., ponderosa pine (Pinus ponderosa Dougl. ex. P. & C. Laws.) and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) of the western United States. We...

  8. Population-Based Study on the Effect of a Forest Environment on Salivary Cortisol Concentration.

    Science.gov (United States)

    Kobayashi, Hiromitsu; Song, Chorong; Ikei, Harumi; Park, Bum-Jin; Lee, Juyoung; Kagawa, Takahide; Miyazaki, Yoshifumi

    2017-08-18

    The purpose of this study was to evaluate the effect of a forest environment on salivary cortisol concentration, particularly on the characteristics of its distribution. The participants were 348 young male subjects. The experimental sites were 34 forests and 34 urban areas across Japan. The subjects viewed the landscape (forest or urban environment) for a period of 15 min while sitting in a chair. Saliva was sampled from the participants at the end of this 15-min period and then analyzed for cortisol concentration. Differences in the skewness and kurtosis of the distributions between the two environments were tested by performing a permutation test. The cortisol concentrations exhibited larger skewness (0.76) and kurtosis (3.23) in a forest environment than in an urban environment (skewness = 0.49; kurtosis = 2.47), and these differences were statistically significant. The cortisol distribution exhibited a more peaked and longer right-tailed curve in a forest environment than in an urban environment.

  9. Tropical secondary forest management influences frugivorous bat composition, abundance and fruit consumption in Chiapas, Mexico.

    Science.gov (United States)

    Vleut, Ivar; Levy-Tacher, Samuel Israel; de Boer, Willem Frederik; Galindo-González, Jorge; Vazquez, Luis-Bernardo

    2013-01-01

    Most studies on frugivorous bat assemblages in secondary forests have concentrated on differences among successional stages, and have disregarded the effect of forest management. Secondary forest management practices alter the vegetation structure and fruit availability, important factors associated with differences in frugivorous bat assemblage structure, and fruit consumption and can therefore modify forest succession. Our objective was to elucidate factors (forest structural variables and fruit availability) determining bat diversity, abundance, composition and species-specific abundance of bats in (i) secondary forests managed by Lacandon farmers dominated by Ochroma pyramidale, in (ii) secondary forests without management, and in (iii) mature rain forests in Chiapas, Southern Mexico. Frugivorous bat species diversity (Shannon H') was similar between forest types. However, bat abundance was highest in rain forest and O. pyramidale forests. Bat species composition was different among forest types with more Carollia sowelli and Sturnira lilium captures in O. pyramidale forests. Overall, bat fruit consumption was dominated by early-successional shrubs, highest late-successional fruit consumption was found in rain forests and more bats consumed early-successional shrub fruits in O. pyramidale forests. Ochroma pyramidale forests presented a higher canopy openness, tree height, lower tree density and diversity of fruit than secondary forests. Tree density and canopy openness were negatively correlated with bat species diversity and bat abundance, but bat abundance increased with fruit abundance and tree height. Hence, secondary forest management alters forests' structural characteristics and resource availability, and shapes the frugivorous bat community structure, and thereby the fruit consumption by bats.

  10. The effect of climate anomalies and human ignition factor on wildfires in Russian boreal forests.

    Science.gov (United States)

    Achard, Frédéric; Eva, Hugh D; Mollicone, Danilo; Beuchle, René

    2008-07-12

    Over the last few years anomalies in temperature and precipitation in northern Russia have been regarded as manifestations of climate change. During the same period exceptional forest fire seasons have been reported, prompting many authors to suggest that these in turn are due to climate change. In this paper, we examine the number and areal extent of forest fires across boreal Russia for the period 2002-2005 within two forest categories: 'intact forests' and 'non-intact forests'. Results show a far lower density of fire events in intact forests (5-14 times less) and that those events tend to be in the first 10 km buffer zone inside intact forest areas. Results also show that, during exceptional climatic years (2002 and 2003), fire event density is twice that found during normal years (2004 and 2005) and average areal extent of fire events (burned area) in intact forests is 2.5 times larger than normal. These results suggest that a majority of the fire events in boreal Russia are of human origin and a maximum of one-third of their impact (areal extension) can be attributed to climate anomalies alone, the rest being due to the combined effect of human disturbances and climate anomalies.

  11. Effects of Burn Severity and Environmental Conditions on Post-Fire Regeneration in Siberian Larch Forest

    Directory of Open Access Journals (Sweden)

    Thuan Chu

    2017-03-01

    Full Text Available Post-fire forest regeneration is strongly influenced by abiotic and biotic heterogeneity in the pre- and post-fire environments, including fire regimes, species characteristics, landforms, hydrology, regional climate, and soil properties. Assessing these drivers is key to understanding the long-term effects of fire disturbances on forest succession. We evaluated multiple factors influencing patterns of variability in a post-fire boreal Larch (Larix sibirica forest in Siberia. A time-series of remote sensing images was analyzed to estimate post-fire recovery as a response variable across the burned area in 1996. Our results suggested that burn severity and water content were primary controllers of both Larch forest recruitment and green vegetation cover as defined by the forest recovery index (FRI and the fractional vegetation cover (FVC, respectively. We found a high rate of Larch forest recruitment in sites of moderate burn severity, while a more severe burn was the preferable condition for quick occupation by vegetation that included early seral communities of shrubs, grasses, conifers and broadleaf trees. Sites close to water and that received higher solar energy during the summer months showed a higher rate of both recovery types, defined by the FRI and FVC, dependent on burn severity. In addition to these factors, topographic variables and pre-fire condition were important predictors of post-fire forest patterns. These results have direct implications for the post-fire forest management in the Siberian boreal Larch region.

  12. Microhabitat effects of litter temperature and moisture on forest-floor invertebrate communities

    Science.gov (United States)

    Tim A. Christiansen; Sue A. Perry; William B. Perry

    1996-01-01

    Litter temperature and moisture may be altered due to changes in global climate. We investigated the effect of small changes in litter temperature and moisture on forest-floor communities in West Virginia.

  13. Effects of ionizing radiation on the boreal forest

    International Nuclear Information System (INIS)

    Amiro, B.D.

    1995-08-01

    The Field-Irradiator-Gamma (FIG) project chronically exposed a section of the boreal forest to ionizing radiation by placing a 137 Cs source on tope of a 20-m tower at a forest site in southeastern Manitoba. The irradiation continued from 1973 to 1986 and the forest was exposed to radiological dose rates ranging from 65 mGy.h -1 to 0.005 mGy.h -1 along a gradient extending 500 m from the source. The irradiation killed the tree canopy close to the irradiator, resulting in the formation of a herbaceous zone of vegetation at high dose rates. After 14 years of irradiation, some tree species were still being affected at dose rates as low as about 1 mGy.h -1 . The data gathered at the FIG site can be used to identify radiological dose rates that forest communities can tolerate. This information allows decisions to be made concerning guidelines for protection of the general environment from radionuclide emissions from various anthropogenic sources, such as nuclear reactors and uranium tailings. This report reviews the previous data collected at the FIG site during the pre-irradiation and irradiation phases and the methodology used to establish a baseline for future comparisons. Permanently marked sampling plots are a particular strength to the study, whereby researchers can compare the present forest community with that measured during the past 25 years. (author). 53 refs., 6 tabs., 22 figs

  14. Neuroprotective Effects and Mechanisms of Curcumin–Cu(II and –Zn(II Complexes Systems and Their Pharmacological Implications

    Directory of Open Access Journals (Sweden)

    Fa-Shun Yan

    2017-12-01

    Full Text Available Alzheimer’s disease (AD is the main form of dementia and has a steadily increasing prevalence. As both oxidative stress and metal homeostasis are involved in the pathogenesis of AD, it would be interesting to develop a dual function agent, targeting the two factors. Curcumin, a natural compound isolated from the rhizome of Curcuma longa, is an antioxidant and can also chelate metal ions. Whether the complexes of curcumin with metal ions possess neuroprotective effects has not been evaluated. Therefore, the present study was designed to investigate the protective effects of the complexes of curcumin with Cu(II or Zn(II on hydrogen peroxide (H2O2-induced injury and the underlying molecular mechanisms. The use of rat pheochromocytoma (PC12 cells, a widely used neuronal cell model system, was adopted. It was revealed that curcumin–Cu(II complexes systems possessed enhanced O2·–-scavenging activities compared to unchelated curcumin. In comparison with unchelated curcumin, the protective effects of curcumin–Cu(II complexes systems were stronger than curcumin–Zn(II system. Curcumin–Cu(II or –Zn(II complexes systems significantly enhanced the superoxide dismutase, catalase, and glutathione peroxidase activities and attenuated the increase of malondialdehyde levels and caspase-3 and caspase-9 activities, in a dose-dependent manner. The curcumin–Cu(II complex system with a 2:1 ratio exhibited the most significant effect. Further mechanistic study demonstrated that curcumin–Cu(II or –Zn(II complexes systems inhibited cell apoptosis via downregulating the nuclear factor κB (NF-κB pathway and upregulating Bcl-2/Bax pathway. In summary, the present study found that curcumin–Cu(II or –Zn(II complexes systems, especially the former, possess significant neuroprotective effects, which indicates the potential advantage of curcumin as a promising agent against AD and deserves further study.

  15. Effects of type II thyroplasty on adductor spasmodic dysphonia.

    Science.gov (United States)

    Sanuki, Tetsuji; Yumoto, Eiji; Minoda, Ryosei; Kodama, Narihiro

    2010-04-01

    Type II thyroplasty, or laryngeal framework surgery, is based on the hypothesis that the effect of adductor spasmodic dysphonia (AdSD) on the voice is due to excessively tight closure of the glottis, hampering phonation. Most of the previous, partially effective treatments have aimed to relieve this tight closure, including recurrent laryngeal nerve section or avulsion, extirpation of the adductor muscle, and botulinum toxin injection, which is currently the most popular. The aim of this study was to assess the effects of type II thyroplasty on aerodynamic and acoustic findings in patients with AdSD. Case series. University hospital. Ten patients with AdSD underwent type II thyroplasty between August 2006 and December 2008. Aerodynamic and acoustic analyses were performed prior to and six months after surgery. Mean flow rates (MFRs) and voice efficiency were evaluated with a phonation analyzer. Jitter, shimmer, the harmonics-to-noise ratio (HNR), standard deviation of the fundamental frequency (SDF0), and degree of voice breaks (DVB) were measured from each subject's longest sustained phonation sample of the vowel /a/. Voice efficiency improved significantly after surgery. No significant difference was found in the MFRs between before and after surgery. Jitter, shimmer, HNR, SDF0, and DVB improved significantly after surgery. Treatment of AdSD with type II thyroplasty significantly improved aerodynamic and acoustic findings. The results of this study suggest that type II thyroplasty provides relief from voice strangulation in patients with AdSD. Copyright 2010 American Academy of Otolaryngology-Head and Neck Surgery Foundation. Published by Mosby, Inc. All rights reserved.

  16. Effects of ground fires on element dynamics in mountainous coniferous forest in Germany

    Directory of Open Access Journals (Sweden)

    Kerstin Näthe

    2012-09-01

    Full Text Available Disturbances such as fires are a natural phenomenon of forested ecosystems, having a different impact on (micro- climate (e.g. emissions of gases and aerosols, ecology (destruction of flora and fauna and nutrient cycles especially in the soils. Forest fires alter the spatial distribution (forest floor vs. mineral soil, binding forms (organic vs. inorganic and availability (water solubility of organic substances and nutrients. The effects of fires on chemical, biological and physical soil properties in forested ecosystems have been intensively studied in the last decades, especially in the Mediterranean area and North America. However, differences in fire intensity, forest type (species, age and location (climate, geological substrate, nutrient status lead to divergent results. Furthermore, only a few case studies focused on the effects of ground fires in hilly landscapes, on the vertical and lateral water-driven fluxes of elements (C, N, nutrients, as well as on the input of fire-released terrestrial nutrients into aquatic ecosystems. Thus, this study will evaluate the effects of low-severity fires on nutrient cycling in a coniferous forest in a hilly landscape connected to an aquatic system. At three spatially independent sites three paired plots (control and manipulated were chosen at a forested site in Thuringia, Germany. All plots are similar in the vegetation cover and pedogenetic properties.In relation to control sites, this study will examine the effects of low-severity fires on:a the mobilization of organic carbon and nutrients (released from ash material and the forest floor via leachate and erosion paths,b the binding form (inorganic/organic of elements and organic compounds, and c the particle size fraction (DOM/POM of elements and organic compounds.The goal of this study is a better understanding of the impact of forest fires on element cycling and release in a hilly landscape connected to an aquatic system, supposedly driven by

  17. Application of a distributed process-based hydrologic model to estimate the effects of forest road density on stormflows in the Southern Appalachians

    Science.gov (United States)

    Salli F. Dymond; W. Michael Aust; Stephen P. Prisley; Mark H. Eisenbies; James M. Vose

    2014-01-01

    Managed forests have historically been linked to watershed protection and flood mitigation. Research indicates that forests can potentially minimize peak flows during storm events, yet the relationship between forests and flooding is complex. Forest roads, usually found in managed systems, can potentially magnify the effects of forest harvesting on water yields. The...

  18. Effects of forest management practices in temperate beech forests on bacterial and fungal communities involved in leaf litter degradation.

    Science.gov (United States)

    Purahong, Witoon; Kapturska, Danuta; Pecyna, Marek J; Jariyavidyanont, Katalee; Kaunzner, Jennifer; Juncheed, Kantida; Uengwetwanit, Tanaporn; Rudloff, Renate; Schulz, Elke; Hofrichter, Martin; Schloter, Michael; Krüger, Dirk; Buscot, François

    2015-05-01

    Forest management practices (FMPs) significantly influence important ecological processes and services in Central European forests, such as leaf litter decomposition and nutrient cycling. Changes in leaf litter diversity, and thus, its quality as well as microbial community structure and function induced by different FMPs were hypothesized to be the main drivers causing shifts in decomposition rates and nutrient release in managed forests. In a litterbag experiment lasting 473 days, we aimed to investigate the effects of FMPs (even-aged timber management, selective logging and unmanaged) on bacterial and fungal communities involved in leaf litter degradation over time. Our results showed that microbial communities in leaf litter were strongly influenced by both FMPs and sampling date. The results from nonmetric multidimensional scaling (NMDS) ordination revealed distinct patterns of bacterial and fungal successions over time in leaf litter. We demonstrated that FMPs and sampling dates can influence a range of factors, including leaf litter quality, microbial macronutrients, and pH, which significantly correlate with microbial community successions.

  19. Cost-effective age structure and geographical distribution of boreal forest reserves.

    Science.gov (United States)

    Lundström, Johanna; Ohman, Karin; Perhans, Karin; Rönnqvist, Mikael; Gustafsson, Lena; Bugman, Harald

    2011-02-01

    1. Forest reserves are established to preserve biodiversity, and to maintain natural functions and processes. Today there is heightened focus on old-growth stages, with less attention given to early successional stages. The biodiversity potential of younger forests has been overlooked, and the cost-effectiveness of incorporating different age classes in reserve networks has not yet been studied.2. We performed a reserve selection analysis in boreal Sweden using the Swedish National Forest Inventory plots. Seventeen structural variables were used as biodiversity indicators, and the cost of protecting each plot as a reserve was assessed using the Heureka system. A goal programming approach was applied, which allowed inclusion of several objectives and avoided a situation in which common indicators affected the result more than rare ones. The model was limited either by budget or area.3. All biodiversity indicators were found in all age classes, with more than half having the highest values in ages ≥ 100 years. Several large-tree indicators and all deadwood indicators had higher values in forests 0-14 years than in forests 15-69 years.4. It was most cost-effective to protect a large proportion of young forests since they generally have a lower net present value compared to older forests, but still contain structures of importance for biodiversity. However, it was more area-effective to protect a large proportion of old forests since they have a higher biodiversity potential per area.5. The geographical distribution of reserves selected with the budget-constrained model was strongly biassed towards the north-western section of boreal Sweden, with a large proportion of young forest, whereas the area-constrained model focussed on the south-eastern section, with dominance by the oldest age class.6.Synthesis and applications. We show that young forests with large amounts of structures important to biodiversity such as dead wood and remnant trees are cheap and cost

  20. Climate change effects on the Dutch forests and forestry; Effecten van klimaatverandering op het Nederlandse bos en bosbeheer

    Energy Technology Data Exchange (ETDEWEB)

    Nabuurs, G.J.; Kramer, K.; Mohren, G.M.J. [IBN-DLO, Wageningen (Netherlands)

    1997-12-31

    The effects of climate change on Dutch forests and forestry will be very drastic when climate change occurs. Changes in the forest ecosystem will affect all functions that the forests provide now. This report presents an overview of the current knowledge of effects of climate change on forests at varying scales of time and space. Where possible the information focuses on the situation in The Netherlands. It also includes an overview of measures which forest management can take to anticipate climate change in order to reduce the effects. 35 refs.

  1. Effects of Forest Bathing on Cardiovascular and Metabolic Parameters in Middle-Aged Males

    Directory of Open Access Journals (Sweden)

    Qing Li

    2016-01-01

    Full Text Available In the present study, we investigated the effects of a forest bathing on cardiovascular and metabolic parameters. Nineteen middle-aged male subjects were selected after they provided informed consent. These subjects took day trips to a forest park in Agematsu, Nagano Prefecture, and to an urban area of Nagano Prefecture as control in August 2015. On both trips, they walked 2.6 km for 80 min each in the morning and afternoon on Saturdays. Blood and urine were sampled before and after each trip. Cardiovascular and metabolic parameters were measured. Blood pressure and pulse rate were measured during the trips. The Japanese version of the profile of mood states (POMS test was conducted before, during, and after the trips. Ambient temperature and humidity were monitored during the trips. The forest bathing program significantly reduced pulse rate and significantly increased the score for vigor and decreased the scores for depression, fatigue, anxiety, and confusion. Urinary adrenaline after forest bathing showed a tendency toward decrease. Urinary dopamine after forest bathing was significantly lower than that after urban area walking, suggesting the relaxing effect of the forest bathing. Serum adiponectin after the forest bathing was significantly greater than that after urban area walking.

  2. Short- and long-term effects of fire on carbon in US dry temperate forest systems

    Science.gov (United States)

    Hurteau, Matthew D.; Brooks, Matthew L.

    2011-01-01

    Forests sequester carbon from the atmosphere, and in so doing can mitigate the effects of climate change. Fire is a natural disturbance process in many forest systems that releases carbon back to the atmosphere. In dry temperate forests, fires historically burned with greater frequency and lower severity than they do today. Frequent fires consumed fuels on the forest floor and maintained open stand structures. Fire suppression has resulted in increased understory fuel loads and tree density; a change in structure that has caused a shift from low- to high-severity fires. More severe fires, resulting in greater tree mortality, have caused a decrease in forest carbon stability. Fire management actions can mitigate the risk of high-severity fires, but these actions often require a trade-off between maximizing carbon stocks and carbon stability. We discuss the effects of fire on forest carbon stocks and recommend that managing forests on the basis of their specific ecologies should be the foremost goal, with carbon sequestration being an ancillary benefit. ?? 2011 by American Institute of Biological Sciences. All rights reserved.

  3. Economic modeling of effects of climate change on the forest sector and mitigation options: a compendium of briefing papers

    Science.gov (United States)

    Ralph J. Alig

    2010-01-01

    This report is a compilation of six briefing papers based on literature reviews and syntheses, prepared for U.S. Department of Agriculture, Forest Service policy analysts and decisionmakers about specific questions pertaining to climate change. The main topics addressed here are economic effects on the forest sector at the national and global scales, costs of forest...

  4. Short- and medium-term effects of fuel reduction mulch treatments on soil nitrogen availability in Colorado conifer forests

    Science.gov (United States)

    C. C. Rhoades; M. A. Battaglia; M. E. Rocca; M. G. Ryan

    2012-01-01

    Mechanical fuel reduction treatments have been implemented on millions of hectares of western North American forests. The redistribution of standing forest biomass to the soil surface by mulching treatments has no ecological analog, and this practice may alter soil processes and forest productivity. We evaluated the effects of mulch addition on soil nitrogen...

  5. Effects of using visualization and animation in presentations to communities about forest succession and fire behavior potential

    Science.gov (United States)

    Jane Kapler Smith; Donald E. Zimmerman; Carol Akerelrea; Garrett O' Keefe

    2008-01-01

    Natural resource managers use a variety of computer-mediated presentation methods to communicate management practices to the public. We explored the effects of using the Stand Visualization System to visualize and animate predictions from the Forest Vegetation Simulator-Fire and Fuels Extension in presentations explaining forest succession (forest growth and change...

  6. Cascading Effects of Canopy Opening and Debris Deposition from a Large-Scale Hurricane Experiment in a Tropical Rain Forest

    Science.gov (United States)

    Aaron B. Shiels; Grizelle Gonzalez; D. Jean Lodge; Michael R Willig; Jess K. Zimmerman

    2015-01-01

    Intense hurricanes disturb many tropical forests, but the key mechanisms driving post-hurricane forest changes are not fully understood. In Puerto Rico, we used a replicated factorial experiment to determine the mechanisms of forest change associated with canopy openness and organic matter (debris) addition. Cascading effects from canopy openness accounted for...

  7. Exploring the role of forest resources in reducing community vulnerability to the heat effects of climate change

    Science.gov (United States)

    Z.L. Walton; N.C. Poudyal; J. Hepinstall; C. Johnson Gaither; B.B. Boley

    2015-01-01

    While the growing literature on forest ecosystem services has examined the value and significance of a range ofservices, our understanding of the health-related benefits of ecosystem services from forests is still limited. Tocharacterize the role of forest resources in reducing community vulnerability to the heat effects of climate...

  8. The effect of organic acids on base cation leaching from the forest floor under six North American tree species

    NARCIS (Netherlands)

    Dijkstra, F.A.; Geibe, C.; Holmstrom, S.; Lundstrom, U.S.; Breemen, van N.

    2001-01-01

    Organic acidity and its degree of neutralization in the forest floor can have large consequences for base cation leaching under different tree species. We investigated the effect of organic acids on base cation leaching from the forest floor under six common North American tree species. Forest floor

  9. Experts’ Perceptions of the Effects of Forest Biomass Harvesting on Sustainability in the Alpine Region

    Directory of Open Access Journals (Sweden)

    Gianluca Grilli

    2015-06-01

    Full Text Available Background and Purpose: In the EU political agenda, the use of forest biomass for energy has grown rapidly and significantly, in order to mitigate carbon dioxide emissions and reduce the energy dependence on fossil fuels of European member countries. The target of the EU climate and energy package is to raise the share of renewable energy consumption produced from renewable resources to 20% in 2020 (Directive 2009/28/EC. With regards to biomass energy, the supply of forest wood biomass is expected to rise by 45% (reference period: 2006-2020, in response to increasing demand for renewable sources. The increase of forest biomass supply could have both positive and negative effects on several forest ecosystem services (ESs and local development. These effects should be assessed in a proper manner and taken into account when formulating management strategies. The aim of the paper is to assess the environmental, economic and social sustainability of forest biomass harvesting for energy, using the Figure of Merit (FoM approach. Materials and Methods: Sustainability was assessed through a set of four indicators: two focused on experts’ opinions regarding the effects of forest biomass harvesting and the other two focused on the cost-benefit analysis (potential energy obtained and costs for wood chips. The research was developed through four case studies located in the Alpine Region. A semi-structured questionnaire was administered face-to-face to 32 selected experts. The perceived effects of forest biomass harvesting for energy on ESs and local development were evaluated by experts using a 5-point Likert scale (from “quite negative effect” to “quite positive effect”. Results: All experts agree that forest biomass harvesting has a positive effect on forest products provision and local economic development (employment of local workforce, local entrepreneurship and market diversification, while the effects on other ESs are controversial (e

  10. Effectiveness of Braun's enteroanastomosis in B II-resected stomach

    International Nuclear Information System (INIS)

    Lindecken, K.D.; Salm, B.

    1993-01-01

    With the aid of hepatobiliary sequence scintigraphy (HBSS) a functional analysis was obtained form 30 patients, subsequent to gastric surgery - after Billroth II with entero-anastomosis - which showed a suprisingly high rate of reflux into the residual stomach, in 16 out of these 30 patients. The high-grade HBSS data with regard to the biliary reflux proportions after gastric surgery and the low-grade effectiveness of Braun's entero-anastomosis are clearly evidenced. (orig./MG) [de

  11. Effects of boreal forest vegetation on global climate

    Science.gov (United States)

    Bonan, Gordon B.; Pollard, David; Thompson, Starley L.

    1992-10-01

    TERRESTRIAL ecosystems are thought to play an important role in determining regional and global climate1-6 one example of this is in Amazonia, where destruction of the tropical rainforest leads to warmer and drier conditions4-6. Boreal forest ecosystems may also affect climate. As temperatures rise, the amount of continental and oceanic snow and ice is reduced, so the land and ocean surfaces absorb greater amounts of solar radiation, reinforcing the warming in a 'snow/ice/albedo' feedback which results in large climate sensitivity to radiative forcings7-9. This sensitivity is moderated, however, by the presence of trees in northern latitudes, which mask the high reflectance of snow10,11, leading to warmer winter temperatures than if trees were not present12-14. Here we present results from a global climate model which show that the boreal forest warms both winter and summer air temperatures, relative to simulations in which the forest is replaced with bare ground or tundra vegetation. Our results suggest that future redistributions of boreal forest and tundra vegetation (due, for example, to extensive logging, or the influence of global warming) could initiate important climate feedbacks, which could also extend to lower latitudes.

  12. Effects of Aluminium in Forest. Results of a pilot experiment

    Energy Technology Data Exchange (ETDEWEB)

    Mulder, J.; Wit, H. de; Nygaard, P.H.

    1996-01-01

    This conference paper deals with an Norwegian pilot project which started in 1995 and finishing early 1999, investigates the solubility and phyto-toxicity of aluminium (Al) in mature forest ecosystems. The project consists of three major parts, including field manipulation study of Norwegian spruce stands, laboratory experiments and modelling Al chemistry in the root zone. 15 refs.

  13. Effects of new forest management strategies on squirrel populations.

    Science.gov (United States)

    Andrew B. Carey

    2000-01-01

    Two strategies for managing forests for multiple values have achieved prominence in debates in the Pacific Northwest: (1) legacy retention with passive management and long rotations, and (2) intensive management for timber with commercial thinnings and long rotations. Northern flying squirrels (Glaucomys sabrinus), Townsend's chipmunks (

  14. The effects of climate stability on northern temperate forests

    DEFF Research Database (Denmark)

    Ma, Ziyu

    2016-01-01

    . The evolutionary relationship among species is known as phylogeny. Tree diversity was mapped using a phylogenetic supertree, covering species in the temperate forests of North America, Europe, and China. I found that Quaternary climate fluctuations limited phylogenetic endemism, which quantified unique...

  15. Simulating Effects of Forest Management Practices on Pesticide.

    Science.gov (United States)

    M.C. Smith; W.G. Knisel; J.L. Michael; D.G. Neary

    1993-01-01

    The GLEAMS model pesticide component was modified to simulate up to 245 pesticides simultaneously, and the revised model was used to pesticide pesticide application windows for forest site preparation and pine release. Five herbicides were made for soils representing four hydrologic soil groups in four climatic regions of the southeastern United States. Five herbicides...

  16. Socio-Economic Analysis Of Income Effects Of Forest Products ...

    African Journals Online (AJOL)

    This study examined the economic importance of exploiting forest products in Enugu State. This study shows that majority of the household heads were between the age of 31 and 50 years. From the study it was found that more of the household heads are males. They engage mainly in different ombined operation in ...

  17. Effect of forest cover on climate with implications for agriculture ...

    African Journals Online (AJOL)

    The results showed forests are responsible for high precipitation and cooler climate which were shown to be the requirements for high productivity of crops and animal husbandry which are dependent upon the availability of surface and ground water that are respectively affected positively and negatively by the levels of ...

  18. Effect of forest canopy on GPS-based movement data

    Science.gov (United States)

    Nicholas J. DeCesare; John R. Squires; Jay A. Kolbe

    2005-01-01

    The advancing role of Global Positioning System (GPS) technology in ecology has made studies of animal movement possible for larger and more vagile species. A simple field test revealed that lengths of GPS-based movement data were strongly biased (Pof forest canopy. Global Positioning System error added an average of 27.5% additional...

  19. Environmental effect studies on a forest ecosystem in Germany

    International Nuclear Information System (INIS)

    Yamamoto, Masayoshi; Bunzl, K.

    1993-01-01

    Long-term acid deposition on a forest ecosystem can have serious impacts on many physicochemical processes in the soil. Since 1984 extensive studies have been carried out in the 'Hoglwald', an old Norway spruce stand near Munich, Germany. In 1986 a variety of radionuclides were deposited in the canopy and on the forest floor of the Hoglwald following the reactor accident at Chernobyl. The amount of 137 Cs from Chernobyl was about 10 times larger than that present in the soil before Chernobyl. Six experimental plots were established in order to study the potential disturbances caused by artificial acid irrigation and compensative liming. Using these fields, investigations on the interception and retention of radionuclides by a coniferous woodland have been done together with the deposition and vertical migration of the radionuclides in the forest. One of the most important results obtained was that 134 Cs deposition velocity in the spruce stand was as high as 5.5 mm/s, and thus higher by a factor of 10 than the corresponding value for the grassland. By evaluating the depth profiles of the Chernobyl-derived 137 Cs in the soil with a compartment model. The fixation of radiocesium in the forest soil was found to be a rather slow process. (author)

  20. Search for Quasi-isodynamic Effects in TJ-II

    International Nuclear Information System (INIS)

    Guasp, J.; Liniers, M.

    2000-01-01

    The possibility of quasi-isodynamics effects (QID) in the TJ-II helical axis Stellarator has been explored maintaining the present setting for the toroidal field coils (TFC). In order to do this it has been necessary to implement a new method of calculation, using real space coordinates to follow the particle trajectories, instated the Boozer coordinates as was usual formerly. The result for the exploration of the flexibility diagram of TJ-II, including magnetic axis a shift effects, has been negative. It seems that there are not useful QID regions in TJ-II with the present setting of TFC carrying equal currents in all coils. Nevertheless, in spite of this negative result, the calculation in real space and, mainly, the grater number of configurations analysed, have produced a series of new important results, some of them unexpected. The influence of rational surfaces is very important. Optima and minima of confinement alternate at both sides of the rational values (mainly for the 1/2 by period) in a way very similar to the radial electric field resonance cases. This effect originates in the peculiar orbit topology in the presence of diffusion. Some lines of study are proposed to deal with this problem. Finally, the negative result of the QID search suggests the convenience to start a similar search without the restriction of equal currents on all the TEC. (Author) 18 refs

  1. Possible effects of the hurricane Gudrun on the regional Swedish forest energy supply

    International Nuclear Information System (INIS)

    Bjoerheden, Rolf

    2007-01-01

    This paper presents a snapshot speculative analysis of some possible effects of the massive windthrow in south Sweden on January 8-9, 2005. Hurricane Gudrun damaged buildings and blocked roads, making large areas inaccessible except by helicopter. Electricity and telecommunications were shambolic. Around 70 million cubic metres were windthrown, equalling a 'normal' Swedish annual felling-a gross value exceeding EUR20,000,000,000. The paper presents the subsequent restoration work that has placed a special focus on the forest sector. In south Sweden, logging work will last for a couple of years. The roundwood market will be severely strained. For individual forest owners, the economic effects of the storm are often disastrous. To ensure that forest owners will retrieve at least part of the pre-storm forest value, restoration aims at the salvaging of maximum value. Sawmills try to store the most valuable timber for years to come, decreasing the risk of painful capacity adjustments and protecting export opportunities. Forest fuel value is low compared to sawlogs and pulpwood. Thus, the forest energy sector has received little attention. Forest chippers normally contribute important marginal quantities of wood fuels, but since no logging residues will be harvested from the windthrown forests for a period of 2-3 years, they are put out of business and may disappear from the market. Heating and power plants will receive an abundance of industrial by-products in the coming 2-3 years, followed by a period of expected shortage of woody biomass for energy production. With few forest chippers left, the situation will be troublesome. (author)

  2. Tropical Secondary Forest Management Influences Frugivorous Bat Composition, Abundance and Fruit Consumption in Chiapas, Mexico

    Science.gov (United States)

    Vleut, Ivar; Levy-Tacher, Samuel Israel; de Boer, Willem Frederik; Galindo-González, Jorge; Vazquez, Luis-Bernardo

    2013-01-01

    Most studies on frugivorous bat assemblages in secondary forests have concentrated on differences among successional stages, and have disregarded the effect of forest management. Secondary forest management practices alter the vegetation structure and fruit availability, important factors associated with differences in frugivorous bat assemblage structure, and fruit consumption and can therefore modify forest succession. Our objective was to elucidate factors (forest structural variables and fruit availability) determining bat diversity, abundance, composition and species-specific abundance of bats in (i) secondary forests managed by Lacandon farmers dominated by Ochroma pyramidale, in (ii) secondary forests without management, and in (iii) mature rain forests in Chiapas, Southern Mexico. Frugivorous bat species diversity (Shannon H’) was similar between forest types. However, bat abundance was highest in rain forest and O. pyramidale forests. Bat species composition was different among forest types with more Carollia sowelli and Sturnira lilium captures in O. pyramidale forests. Overall, bat fruit consumption was dominated by early-successional shrubs, highest late-successional fruit consumption was found in rain forests and more bats consumed early-successional shrub fruits in O. pyramidale forests. Ochroma pyramidale forests presented a higher canopy openness, tree height, lower tree density and diversity of fruit than secondary forests. Tree density and canopy openness were negatively correlated with bat species diversity and bat abundance, but bat abundance increased with fruit abundance and tree height. Hence, secondary forest management alters forests’ structural characteristics and resource availability, and shapes the frugivorous bat community structure, and thereby the fruit consumption by bats. PMID:24147029

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

    Science.gov (United States)

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

    2017-12-01

    Climate change is expected to increase drought stress in many forests and alter fire regimes. Fire can reduce tree density and thus competition for limited water, but the effects of changing fire regimes on forest productivity during drought remain poorly understood. We measured the annual ring-widths of adult oak (Quercus spp.) trees in Mark Twain National Forest, Missouri USA that experienced unburned, annual or periodic (every 4 years) surface fire treatments from 1951 - 2015. Severe drought events were identified using the BILJOU water balance model. We determined the effect of fire treatment on stand-level annual growth rates as well as stand-level resistance and resilience to drought, defined as the drought-induced reduction in growth and post-drought recovery in growth, respectively. During favorable wet years, annual and periodic fire treatments reduced annual growth rates by approximately 10-15% relative to unburned controls (P forest productivity.

  4. Effects of angiotensin II and angiotensin II type 1 receptor blockade on neointimal formation after stent implantation

    NARCIS (Netherlands)

    Groenewegen, Hendrik C.; van der Harst, Pim; Roks, Anton J. M.; Buikema, Hendrik; Zijlstra, Felix; van Gilst, Wiek H.; de Smet, Bart J. G. L.

    2008-01-01

    Background: To evaluate the effect of supraphysiological levels of angiotensin II and selective angiotensin II type 1 receptor ( AT1-receptor) blockade on neointimal formation and systemic endothelial function after stent implantation in the rat abdominal aorta. Methods: Male Wistar rats were

  5. Reach-scale effects of riparian forest cover on urban stream ecosystems

    Science.gov (United States)

    Roy, A.H.; Faust, C.L.; Freeman, Mary C.; Meyer, J.L.

    2005-01-01

    We compared habitat and biota between paired open and forested reaches within five small streams (basin area 10?20 km2) in suburban catchments (9%?49% urban land cover) in the Piedmont of Georgia, USA. Stream reaches with open canopies were narrower than forested reaches (4.1 versus 5.0 m, respectively). There were no differences in habitat diversity (variation in velocity, depth, or bed particle size) between open and forested reaches. However, absence of local forest cover corresponded to decreased large wood and increased algal chlorophyll a standing crop biomass. These differences in basal food resources translated into higher densities of fishes in open (9.0 individuals?m?2) versus forested (4.9 individuals?m?2) reaches, primarily attributed to higher densities of the herbivore Campostoma oligolepis. Densities of terrestrial invertebrate inputs were higher in open reaches; however, trends suggested higher biomass of terrestrial inputs in forested reaches and a corresponding higher density of terrestrial prey consumed by water column feeding fishes. Reach-scale biotic integrity (macroinvertebrates, salamanders, and fishes) was largely unaffected by differences in canopy cover. In urbanizing areas where catchment land cover drives habitat and biotic quality, management practices that rely exclusively on forested riparian areas for stream protection are unlikely to be effective at maintaining ecosystem integrity.

  6. Nutrient addition effects on tropical dry forests: a mini-review from microbial to ecosystem scales

    Directory of Open Access Journals (Sweden)

    Jennifer S. Powers

    2015-06-01

    Full Text Available Humans have more than doubled inputs of reactive nitrogen globally and greatly accelerated the biogeochemical cycles of phosphorus and metals. However, the impacts of increased element mobility on tropical ecosystems remain poorly quantified, particularly for the vast tropical dry forest biome. Tropical dry forests are characterized by marked seasonality, relatively little precipitation, and high heterogeneity in plant functional diversity and soil chemistry. For these reasons, increased nutrient deposition may affect tropical dry forests differently than wet tropical or temperate forests. Here we review studies that investigated how nutrient availability affects ecosystem and community processes from the microsite to ecosystem scales in tropical dry forests. The effects of N and P addition on ecosystem carbon cycling and plant and microbial dynamics depend on forest successional stage, soil parent material and rainfall regime. Responses may depend on whether overall productivity is N- versus P-limited, although data to test this hypothesis are limited. These results highlight the many important gaps in our understanding of tropical dry forest responses to global change. Large-scale experiments are required to resolve these uncertainties.

  7. Nutrient addition effects on tropical dry forests: a mini-review from microbial to ecosystem scales

    Science.gov (United States)

    Powers, Jennifer; Becklund, Kristen; Gei, Maria; Iyengar, Siddarth; Meyer, Rebecca; O'Connell, Christine; Schilling, Erik; Smith, Christina; Waring, Bonnie; Werden, Leland

    2015-06-01

    Humans have more than doubled inputs of reactive nitrogen globally and greatly accelerated the biogeochemical cycles of phosphorus and metals. However, the impacts of increased element mobility on tropical ecosystems remain poorly quantified, particularly for the vast tropical dry forest biome. Tropical dry forests are characterized by marked seasonality, relatively little precipitation, and high heterogeneity in plant functional diversity and soil chemistry. For these reasons, increased nutrient deposition may affect tropical dry forests differently than wet tropical or temperate forests. Here we review studies that investigated how nutrient availability affects ecosystem and community processes from the microsite to ecosystem scales in tropical dry forests. The effects of N and P addition on ecosystem carbon cycling and plant and microbial dynamics depend on forest successional stage, soil parent material and rainfall regime. Responses may depend on whether overall productivity is N- versus P-limited, although data to test this hypothesis are limited. These results highlight the many important gaps in our understanding of tropical dry forest responses to global change. Large-scale experiments are required to resolve these uncertainties.

  8. 76 FR 26239 - Umatilla National Forest, Walla Walla Ranger District, Oregon, Cobbler II Timber Sale and Fuels...

    Science.gov (United States)

    2011-05-06

    ...; 1415 W. Rose; Walla Walla, Washington 99362. FOR FURTHER INFORMATION CONTACT: Kimpton Cooper, 509-522... can be found on the Umatilla National Forest Web site at ( http://www.fs.fed.us/nepa/nepa_test/fs-usda...

  9. Climate effects on vegetation vitality at the treeline of boreal forests of Mongolia

    Science.gov (United States)

    Klinge, Michael; Dulamsuren, Choimaa; Erasmi, Stefan; Nikolaus Karger, Dirk; Hauck, Markus

    2018-03-01

    In northern Mongolia, at the southern boundary of the Siberian boreal forest belt, the distribution of steppe and forest is generally linked to climate and topography, making this region highly sensitive to climate change and human impact. Detailed investigations on the limiting parameters of forest and steppe in different biomes provide necessary information for paleoenvironmental reconstruction and prognosis of potential landscape change. In this study, remote sensing data and gridded climate data were analyzed in order to identify main distribution patterns of forest and steppe in Mongolia and to detect environmental factors driving forest development. Forest distribution and vegetation vitality derived from the normalized differentiated vegetation index (NDVI) were investigated for the three types of boreal forest present in Mongolia (taiga, subtaiga and forest-steppe), which cover a total area of 73 818 km2. In addition to the forest type areas, the analysis focused on subunits of forest and nonforested areas at the upper and lower treeline, which represent ecological borders between vegetation types. Climate and NDVI data were analyzed for a reference period of 15 years from 1999 to 2013. The presented approach for treeline delineation by identifying representative sites mostly bridges local forest disturbances like fire or tree cutting. Moreover, this procedure provides a valuable tool to distinguish the potential forested area. The upper treeline generally rises from 1800 m above sea level (a.s.l.) in the northeast to 2700 m a.s.l. in the south. The lower treeline locally emerges at 1000 m a.s.l. in the northern taiga and rises southward to 2500 m a.s.l. The latitudinal gradient of both treelines turns into a longitudinal one on the eastern flank of mountain ranges due to higher aridity caused by rain-shadow effects. Less productive trees in terms of NDVI were identified at both the upper and lower treeline in relation to the respective total boreal forest

  10. Effects of fire on spotted owl site occupancy in a late-successional forest

    Science.gov (United States)

    Roberts, Susan L.; van Wagtendonk, Jan W.; Miles, A. Keith; Kelt, Douglas A.

    2011-01-01

    The spotted owl (Strix occidentalis) is a late-successional forest dependent species that is sensitive to forest management practices throughout its range. An increase in the frequency and spatial extent of standreplacing fires in western North America has prompted concern for the persistence of spotted owls and other sensitive late-successional forest associated species. However, there is sparse information on the effects of fire on spotted owls to guide conservation policies. In 2004-2005, we surveyed for California spotted owls during the breeding season at 32 random sites (16 burned, 16 unburned) throughout late-successional montane forest in Yosemite National Park, California. Our burned areas burned at all severities, but predominately involved low to moderate fire severity. Based on an information theoretic approach, spotted owl detection and occupancy rates were similar between burned and unburned sites. Nest and roost site occupancy was best explained by a model that combined total tree basal area (positive effect) with cover by coarse woody debris (negative effect). The density estimates of California spotted owl pairs were similar in burned and unburned forests, and the overall mean density estimate for Yosemite was higher than previously reported for montane forests. Our results indicate that low to moderate severity fires, historically common within montane forests of the Sierra Nevada, California, maintain habitat characteristics essential for spotted owl site occupancy. These results suggest that managed fires that emulate the historic fire regime of these forests may maintain spotted owl habitat and protect this species from the effects of future catastrophic fires.

  11. Edge effects and beta diversity in ground and canopy beetle communities of fragmented subtropical forest.

    Science.gov (United States)

    Stone, Marisa J; Catterall, Carla P; Stork, Nigel E

    2018-01-01

    Clearing of dry forests globally creates edges between remnant forest and open anthropogenic habitats. We used flight intercept traps to evaluate how forest beetle communities are influenced by distance from such edges, together with vertical height, spatial location, and local vegetation structure, in an urbanising region (Brisbane, Australia). Species composition (but not total abundance or richness) differed greatly between ground and canopy. Species composition also varied strongly among sites at both ground and canopy levels, but almost all other significant effects occurred only at ground level, where: species richness declined from edge to interior; composition differed between positions near edges ( 50 m); high local canopy cover was associated with greater total abundance and richness and differing composition; and greater distances to the city centre were associated with increased total abundances and altered composition. Analyses of individual indicator species associated with this variation enabled further biological interpretations. A global literature synthesis showed that most spatially well-replicated studies of edge effects on ground-level beetles within forest fragments have likewise found that positions within tens of metres from edges with open anthropogenic habitats had increased species richness and different compositions from forest interior sites, with fewer effects on abundance. Accordingly, negative edge effects will not prevent relatively small compact fragments (if >10-20 ha) from supporting forest-like beetle communities, although indirect consequences of habitat degradation remain a threat. Retention of multiple spatially scattered forest areas will also be important in conserving forest-dependent beetles, given high levels of between-site diversity.

  12. Urbanization Impacts on Mammals across Urban-Forest Edges and a Predictive Model of Edge Effects

    OpenAIRE

    Villaseñor, Nélida R.; Driscoll, Don A.; Escobar, Martín A. H.; Gibbons, Philip; Lindenmayer, David B.

    2014-01-01

    With accelerating rates of urbanization worldwide, a better understanding of ecological processes at the wildland-urban interface is critical to conserve biodiversity. We explored the effects of high and low-density housing developments on forest-dwelling mammals. Based on habitat characteristics, we expected a gradual decline in species abundance across forest-urban edges and an increased decline rate in higher contrast edges. We surveyed arboreal mammals in sites of high and low housing den...

  13. Local versus landscape-scale effects of anthropogenic land-use on forest species richness

    Science.gov (United States)

    Buffa, G.; Del Vecchio, S.; Fantinato, E.; Milano, V.

    2018-01-01

    The study investigated the effects of human-induced landscape patterns on species richness in forests. For 80 plots of fixed size, we measured human disturbance (categorized as urban/industrial and agricultural land areas), at 'local' and 'landscape' scale (500 m and 2500 m radius from each plot, respectively), the distance from the forest edge, and the size and shape of the woody patch. By using GLM, we analyzed the effects of disturbance and patch-based measures on both total species richness and the richness of a group of specialist species (i.e. the 'ancient forest species'), representing more specific forest features. Patterns of local species richness were sensitive to the structure and composition of the surrounding landscape. Among the landscape components taken into account, urban/industrial land areas turned out as the most threatening factor for both total species richness and the richness of the ancient forest species. However, the best models evidenced a different intensity of the response to the same disturbance category as well as a different pool of significant variables for the two groups of species. The use of groups of species, such as the ancient forest species pool, that are functionally related and have similar ecological requirements, may represent an effective solution for monitoring forest dynamics under the effects of external factors. The approach of relating local assessment of species richness, and in particular of the ancient forest species pool, to land-use patterns may play an important role for the science-policy interface by supporting and strengthening conservation and regional planning decision making.

  14. Edge effects and beta diversity in ground and canopy beetle communities of fragmented subtropical forest

    Science.gov (United States)

    Catterall, Carla P.; Stork, Nigel E.

    2018-01-01

    Clearing of dry forests globally creates edges between remnant forest and open anthropogenic habitats. We used flight intercept traps to evaluate how forest beetle communities are influenced by distance from such edges, together with vertical height, spatial location, and local vegetation structure, in an urbanising region (Brisbane, Australia). Species composition (but not total abundance or richness) differed greatly between ground and canopy. Species composition also varied strongly among sites at both ground and canopy levels, but almost all other significant effects occurred only at ground level, where: species richness declined from edge to interior; composition differed between positions near edges ( 50 m); high local canopy cover was associated with greater total abundance and richness and differing composition; and greater distances to the city centre were associated with increased total abundances and altered composition. Analyses of individual indicator species associated with this variation enabled further biological interpretations. A global literature synthesis showed that most spatially well-replicated studies of edge effects on ground-level beetles within forest fragments have likewise found that positions within tens of metres from edges with open anthropogenic habitats had increased species richness and different compositions from forest interior sites, with fewer effects on abundance. Accordingly, negative edge effects will not prevent relatively small compact fragments (if >10–20 ha) from supporting forest-like beetle communities, although indirect consequences of habitat degradation remain a threat. Retention of multiple spatially scattered forest areas will also be important in conserving forest-dependent beetles, given high levels of between-site diversity. PMID:29494680

  15. Landscape-level effects on aboveground biomass of tropical forests: A conceptual framework.

    Science.gov (United States)

    Melito, Melina; Metzger, Jean Paul; de Oliveira, Alexandre A

    2018-02-01

    Despite the general recognition that fragmentation can reduce forest biomass through edge effects, a systematic review of the literature does not reveal a clear role of edges in modulating biomass loss. Additionally, the edge effects appear to be constrained by matrix type, suggesting that landscape composition has an influence on biomass stocks. The lack of empirical evidence of pervasive edge-related biomass losses across tropical forests highlights the necessity for a general framework linking landscape structure with aboveground biomass. Here, we propose a conceptual model in which landscape composition and configuration mediate the magnitude of edge effects and seed-flux among forest patches, which ultimately has an influence on biomass. Our model hypothesizes that a rapid reduction of biomass can occur below a threshold of forest cover loss. Just below this threshold, we predict that changes in landscape configuration can strongly influence the patch's isolation, thus enhancing biomass loss. Moreover, we expect a synergism between landscape composition and patch attributes, where matrix type mediates the effects of edges on species decline, particularly for shade-tolerant species. To test our conceptual framework, we propose a sampling protocol where the effects of edges, forest amount, forest isolation, fragment size, and matrix type on biomass stocks can be assessed both collectively and individually. The proposed model unifies the combined effects of landscape and patch structure on biomass into a single framework, providing a new set of main drivers of biomass loss in human-modified landscapes. We argue that carbon trading agendas (e.g., REDD+) and carbon-conservation initiatives must go beyond the effects of forest loss and edges on biomass, considering the whole set of effects on biomass related to changes in landscape composition and configuration. © 2017 John Wiley & Sons Ltd.

  16. Challenges in elevated CO2 experiments on forests

    DEFF Research Database (Denmark)

    Calfapietra, Carlo; Ainsworth, Elizabeth A.; Beier, Claus

    2010-01-01

    scientific questions and how can they be addressed? (ii) What forest ecosystems should be investigated? (iii) Which other climate change factors should be coupled with elevated CO2 concentrations in future experiments to better predict the effects of climate change? Plantations and natural forests can have...

  17. [Effect of forest therapy on the human psycho-neuro-endocrino-immune network].

    Science.gov (United States)

    Li, Qing; Kawada, Tomoyuki

    2011-09-01

    Traditional thinking considered the nervous system, endocrine system and immune system to be independent of each other. However, it is now widely accepted that these systems interact through the psycho-neuro-endocrino-immune network. The nervous system affects the endocrine and immune systems by releasing neurotransmitters through the hypothalamus in the hypothalamic-pituitary portal circulation. The endocrine system affects the nervous and immune systems by secreting hormones and the immune system feeds back to the nervous and endocrine systems via cytokines. Forest therapy reduces sympathetic nervous activity, increases parasympathetic nervous activity, and regulates the balance of autonomic nerves. As a result, forest therapy decreases blood pressure and heart rate and has a relaxing effect. Forest therapy affects psychological responses via the brain and nervous system thereby decreasing the scores for anxiety, depression, anger, fatigue, and confusion, and increasing the score for vigor in the POMS test. Forest therapy acts on the endocrine system to reduce stress hormone levels such as urinary adrenaline, urinary noradrenaline, salivary cortisol, and blood cortisol levels and shows a relaxing effect. Forest therapy also acts directly and indirectly on the immune system to promote NK activity by increasing the number of NK cells and intracellular levels of anticancer proteins such as perforin, granulysin and granzymes. Taken together, forest therapy brings various effects on human health via the psycho-neuro-endocrino-immune network.

  18. Neurological Adverse Effects after Radiation Therapy for Stage II Seminoma

    DEFF Research Database (Denmark)

    Ebbeskov Lauritsen, Liv; Meidahl Petersen, Peter; Daugaard, Gedske

    2012-01-01

    We report 3 cases of patients with testicular cancer and stage II seminoma who developed neurological symptoms with bilateral leg weakness about 4 to 9 months after radiation therapy (RT). They all received RT to the para-aortic lymph nodes with a total dose of 40 Gy (36 Gy + 4 Gy as a boost....../or to the spinal cord. RT is believed to produce plexus injury by both direct toxic effects and secondary microinfarction of the nerves, but the exact pathophysiology of RT-induced injury is unclear. Since reported studies of radiation-induced neurological adverse effects are limited, it is difficult to estimate...

  19. Edge effects on moisture reduce wood decomposition rate in a temperate forest.

    Science.gov (United States)

    Crockatt, Martha E; Bebber, Daniel P

    2015-02-01

    Forests around the world are increasingly fragmented, and edge effects on forest microclimates have the potential to affect ecosystem functions such as carbon and nutrient cycling. Edges tend to be drier and warmer due to the effects of insolation, wind, and evapotranspiration and these gradients can penetrate hundreds of metres into the forest. Litter decomposition is a key component of the carbon cycle, which is largely controlled by saprotrophic fungi that respond to variation in temperature and moisture. However, the impact of forest fragmentation on litter decay is poorly understood. Here, we investigate edge effects on the decay of wood in a temperate forest using an experimental approach, whereby mass loss in wood blocks placed along 100 m transects from the forest edge to core was monitored over 2 years. Decomposition rate increased with distance from the edge, and was correlated with increasing humidity and moisture content of the decaying wood, such that the decay constant at 100 m was nearly twice that at the edge. Mean air temperature decreased slightly with distance from the edge. The variation in decay constant due to edge effects was larger than that expected from any reasonable estimates of climatic variation, based on a published regional model. We modelled the influence of edge effects on the decay constant at the landscape scale using functions for forest area within different distances from edge across the UK. We found that taking edge effects into account would decrease the decay rate by nearly one quarter, compared with estimates that assumed no edge effect. © 2014 John Wiley & Sons Ltd.

  20. Effects of nitrogen additions on above- and belowground carbon dynamics in two tropical forests

    Energy Technology Data Exchange (ETDEWEB)

    Cusack, D.; Silver, W.L.; Torn, M.S.; McDowell, W.H.

    2011-04-15

    Anthropogenic nitrogen (N) deposition is increasing rapidly in tropical regions, adding N to ecosystems that often have high background N availability. Tropical forests play an important role in the global carbon (C) cycle, yet the effects of N deposition on C cycling in these ecosystems are poorly understood. We used a field N-fertilization experiment in lower and upper elevation tropical rain forests in Puerto Rico to explore the responses of above- and belowground C pools to N addition. As expected, tree stem growth and litterfall productivity did not respond to N fertilization in either of these Nrich forests, indicating a lack of N limitation to net primary productivity (NPP). In contrast, soil C concentrations increased significantly with N fertilization in both forests, leading to larger C stocks in fertilized plots. However, different soil C pools responded to N fertilization differently. Labile (low density) soil C fractions and live fine roots declined with fertilization, while mineral-associated soil C increased in both forests. Decreased soil CO2 fluxes in fertilized plots were correlated with smaller labile soil C pools in the lower elevation forest (R2 = 0.65, p\\0.05), and with lower live fine root biomass in the upper elevation forest (R2 = 0.90, p\\0.05). Our results indicate that soil C storage is sensitive to N deposition in tropical forests, even where plant productivity is not N-limited. The mineral-associated soil C pool has the potential to respond relatively quickly to N additions, and can drive increases in bulk soil C stocks in tropical forests.

  1. Effects of exotic plantation forests on soil edaphon and organic matter fractions.

    Science.gov (United States)

    Xu, Gang; Liu, Yao; Long, Zhijian; Hu, Shanglian; Zhang, Yuanbin; Jiang, Hao

    2018-06-01

    There is uncertainty and limited knowledge regarding soil microbial properties and organic matter fractions of natural secondary forest accompanying chemical environmental changes of replacement by pure alien plantation forests in a hilly area of southwest of Sichuan province China. The aim of this study was to evaluate the impact of natural secondary forest (NSF) to pure Cryptomeria fortunei forest (CFF) and Cunninghamia lanceolata forest (CLF) on soil organic fractions and microbial communities. The results showed that the soil total phospholipid fatty acids (PLFAs), total bacteria and fungi, microbial carbon pool, organic recalcitrant carbon (C) and (N) fractions, soil microbial quotient and labile and recalcitrant C use efficiencies in each pure plantation were significantly decreased, but their microbial N pool, labile C and N pools, soil carbon dioxide efflux, soil respiratory quotient and recalcitrant N use efficiency were increased. An RDA analysis revealed that soil total PLFAs, total bacteria and fungi and total Gram-positive and Gram-negative bacteria were significantly associated with exchangeable Al 3+ , exchangeable acid, Al 3+ , available P and Mg 2+ and pH, which resulted into microbial functional changes of soil labile and recalcitrant substrate use efficiencies. Modified microbial C- and N-use efficiency due to forest conversion ultimately meets those of rapidly growing trees in plantation forests. Enlarged soil labile fractions and soil respiratory quotients in plantation forests would be a potential positive effect for C source in the future forest management. Altogether, pure plantation practices could provoke regulatory networks and functions of soil microbes and enzyme activities, consequently leading to differentiated utilization of soil organic matter fractions accompanying the change in environmental factors. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Effects of elevated nitrogen deposition on the field-layer vegetation in coniferous forests

    Energy Technology Data Exchange (ETDEWEB)

    Kellner, O. [Swedish Univ. of Agricultural Science, Dept. of Ecology and Enviromental Research, Uppsala (Sweden); Redbo-Torstensson, P. [Uppsala Univ., Dept. of Ecological Botany, Uppsala (Sweden)

    1995-12-31

    Time series studies on vegetation changes in European coniferous forests are reviewed in relation to nitrogen deposition. In areas with high N deposition, grasses had increased together with mean indicator values for nitrogen. The same type of changes have been recorded in nitrogen fertilization experiments. In order to investigate whether such vegetation changes only take place at high N deposition levels, we performed a five-year experiment in which nitrogen was applied to the field layer in a coniferous forest in central Sweden. There were five different fertilization treatments: i) control with no extra nitrogen, ii) 0.5, iii) 1.0, iv) 2.0, and v) 4.0 g N m{sup -2} yr{sup -1}. Six species were present in sufficient amounts to make analyses of changes possible: Deschampsia flexuosa, Linnaea borealis, luzula pilosa, Trientalis europaea, Vaccinium myrtillus and V. vitis-idaea. for only two of these species (D. flexuosa and T. europaea) was there a significant effect of the nitrogen treatment. A third species (V. myrtillus) changed significantly through the years, but showed no effect of nitrogen. For D. fluxuosa, the magnitude of the increase in shoot density after five years was closely related to the amount of nitrogen added. In control plots it shoot density remained fairly constant. Ramet density of T. europaea more than doubled in the two treatments with the lowest amounts of added nitrogen, and increased more than five times in the two highest treatments. In the control treatment ramet density was fairly constant. Vaccinium myrtillus increased in density during the five years, from 36 ramets m{sup -2} in 1988 to 46 m{sup -2} 1992. The increase in ramet density was observed in all treatments and we detected no significant effect of nitrogen treatments. Our results indicate that changes in the field layer are induced already at low deposition rates (0.5 g N m{sup - }yr{sup -1} in through-fall). (Abstract Truncated)

  3. Regional atmospheric cooling and wetting effect of permafrost thaw-induced boreal forest loss.

    Science.gov (United States)

    Helbig, Manuel; Wischnewski, Karoline; Kljun, Natascha; Chasmer, Laura E; Quinton, William L; Detto, Matteo; Sonnentag, Oliver

    2016-12-01

    In the sporadic permafrost zone of North America, thaw-induced boreal forest loss is leading to permafrost-free wetland expansion. These land cover changes alter landscape-scale surface properties with potentially large, however, still unknown impacts on regional climates. In this study, we combine nested eddy covariance flux tower measurements with satellite remote sensing to characterize the impacts of boreal forest loss on albedo, eco-physiological and aerodynamic surface properties, and turbulent energy fluxes of a lowland boreal forest region in the Northwest Territories, Canada. Planetary boundary layer modelling is used to estimate the potential forest loss impact on regional air temperature and atmospheric moisture. We show that thaw-induced conversion of forests to wetlands increases albedo: and bulk surface conductance for water vapour and decreases aerodynamic surface temperature. At the same time, heat transfer efficiency is reduced. These shifts in land surface properties increase latent at the expense of sensible heat fluxes, thus, drastically reducing Bowen ratios. Due to the lower albedo of forests and their masking effect of highly reflective snow, available energy is lower in wetlands, especially in late winter. Modelling results demonstrate that a conversion of a present-day boreal forest-wetland to a hypothetical homogeneous wetland landscape could induce a near-surface cooling effect on regional air temperatures of up to 3-4 °C in late winter and 1-2 °C in summer. An atmospheric wetting effect in summer is indicated by a maximum increase in water vapour mixing ratios of 2 mmol mol -1 . At the same time, maximum boundary layer heights are reduced by about a third of the original height. In fall, simulated air temperature and atmospheric moisture between the two scenarios do not differ. Therefore, permafrost thaw-induced boreal forest loss may modify regional precipitation patterns and slow down regional warming trends. © 2016 John Wiley

  4. Effects of Natural Atlantic Forest Regeneration on Soil Fauna, Brazil

    Directory of Open Access Journals (Sweden)

    Rodrigo Camara

    2017-12-01

    Full Text Available Abstract The stage of natural forest regeneration may influence soil fauna. This study aimed to test the hypothesis that there are differences in the structure and composition of the soil fauna communities between areas undergoing less advanced (LAS and more advanced (MAS stages of natural regeneration of Seasonal Semideciduous Forest at Pinheiral, RJ. Soil fauna was sampled using pitfall traps, during dry and rainy seasons. Total abundance, abundance of the saprophagous/predator group, mainly Formicidae, and the relative participation of Orthoptera were higher in MAS, while the relative participation of Acari, Araneae, Coleoptera, Diptera and the herbivorous group were higher in LAS, during both climatic seasons. Some taxonomic groups were restricted to one of the areas. Richness, evenness and diversity tended to present higher values in LAS (dry season. The higher complexity of the soil fauna community was correlated to the higher leaf litter standing stock in LAS.

  5. Effects of model choice and forest structure on inventory-based estimations of Puerto Rican forest biomass

    Science.gov (United States)

    Thomas J. Brandeis; Maria Del Rocio; Suarez Rozo

    2005-01-01

    Total aboveground live tree biomass in Puerto Rican lower montane wet, subtropical wet, subtropical moist and subtropical dry forests was estimated using data from two forest inventories and published regression equations. Multiple potentially-applicable published biomass models existed for some forested life zones, and their estimates tended to diverge with increasing...

  6. The effect of expertise on the quality of forest standards implementation: The case of FSC forest certification in Russia

    NARCIS (Netherlands)

    Maletz, O.; Tysiachniouk, M.S.

    2009-01-01

    The central question of the paper is how differences in expertise affect the implementation of voluntary environmental standards in the forestry sector. Specifically we analyze the experience of two large forest companies in Russia that certified their forest management under the Forest Stewardship

  7. FORECO. Countermeasures applied in forest ecosystems and their secondary effects: a review of literature

    Energy Technology Data Exchange (ETDEWEB)

    Rafferty, B.; Synnot, H. [Radiological Protection Institute of Ireland, (Ireland)

    1998-12-31

    The present document reports a literature review of the countermeasures applied in forest ecosystems and their secondary effects. The review has been prepared as a deliverable for the FORECO research Project. FORECO (Forest Ecosystems: Classification of Restoration Options, Considering Dose Reduction, Long-Term Ecological Quality and Economic Factors) is a project funded by the European Commission (Research Contract n. ERBIC-CT96-0202) in the frame of the Cooperation with third countries and international organizations (INCO-COPERNICUS) and coordinated by the National Environmental Protection Agency of Italy. The main aim of FORECO activities with respect to forest ecosystems is the classification of countermeasure options in different forest types, considering the balance between dose reduction, long-term ecological quality and economical factors.

  8. FORECO. Countermeasures applied in forest ecosystems and their secondary effects. A review of literature

    International Nuclear Information System (INIS)

    Rafferty, B.; Synnot, H.

    1998-01-01

    The present document reports a literature review of the countermeasures applied in forest ecosystems and their secondary effects. The review has been prepared as a deliverable for the FORECO research Project. FORECO (Forest Ecosystems: Classification of Restoration Options, Considering Dose Reduction, Long-Term Ecological Quality and Economic Factors) is a project funded by the European Commission (Research Contract n. ERBIC-CT96-0202) in the frame of the Cooperation with third countries and international organizations (INCO-COPERNICUS) and coordinated by the National Environmental Protection Agency of Italy. The main aim of FORECO activities with respect to forest ecosystems is the classification of countermeasure options in different forest types, considering the balance between dose reduction, long-term ecological quality and economical factors

  9. The impact of future forest dynamics on climate: interactive effects of changing vegetation and disturbance regimes.

    Science.gov (United States)

    Thom, Dominik; Rammer, Werner; Seidl, Rupert

    2017-11-01

    Currently, the temperate forest biome cools the earth's climate and dampens anthropogenic climate change. However, climate change will substantially alter forest dynamics in the future, affecting the climate regulation function of forests. Increasing natural disturbances can reduce carbon uptake and evaporative cooling, but at the same time increase the albedo of a landscape. Simultaneous changes in vegetation composition can mitigate disturbance impacts, but also influence climate regulation directly (e.g., via albedo changes). As a result of a number of interactive drivers (changes in climate, vegetation, and disturbance) and their simultaneous effects on climate-relevant processes (carbon exchange, albedo, latent heat flux) the future climate regulation function of forests remains highly uncertain. Here we address these complex interactions to assess the effect of future forest dynamics on the climate system. Our specific objectives were (1) to investigate the long-term interactions between changing vegetation composition and disturbance regimes under climate change, (2) to quantify the response of climate regulation to changes in forest dynamics, and (3) to identify the main drivers of the future influence of forests on the climate system. We investigated these issues using the individual-based forest landscape and disturbance model (iLand). Simulations were run over 200 yr for Kalkalpen National Park (Austria), assuming different future climate projections, and incorporating dynamically responding wind and bark beetle disturbances. To consistently assess the net effect on climate the simulated responses of carbon exchange, albedo, and latent heat flux were expressed as contributions to radiative forcing. We found that climate change increased disturbances (+27.7% over 200 yr) and specifically bark beetle activity during the 21st century. However, negative feedbacks from a simultaneously changing tree species composition (+28.0% broadleaved species) decreased

  10. Effects of Forest Cover Change on Flood Characteristics in the Upper Citarum Watershed

    Directory of Open Access Journals (Sweden)

    Bambang Dwi Dasanto

    2014-12-01

    Full Text Available Information on the effect of forest cover changes on streamflow (river discharge in large-scale catchment is important to be studied. The rate of forest cover change in the Upper Citarum Watershed as a large-scale catchment is high enough to drive streamflow change, such as increase of discharge level, or flood volume. Within the research area, flood would occur when the volume of streamflow exceeded the canal capacity and inundated areas that were normally dry. Therefore, this research focused on identifying the effects of forest cover change on flood events and its distribution. The research consisted of 2 main stages; firstly, building geometric data of river and performing frequency analysis of historical and scenario discharges using an approach of probability distribution; and, secondly, flood inundation mapping using HEC-RAS model. The results showed that forest reduction have affected water yield in the downstream of Upper Citarum Watershed. In each return period, this reduction have increased river discharge level and affected the spread of flooded areas. In 2-year return period, the extent of flood as an impact of forest reduction was estimated to decrease slowly. However, in the return period of more than 2 years, the spread of flooded areas increased sharply. These proved that forest cover reduction would always increase the discharge value, but it did not always expand the inundated area.

  11. EUFODOS: European Forest Downstream Services - Improved Information on Forest Structure and Damage

    Science.gov (United States)

    Hirschmugl, M.; Gallaun, H.; Wack, R.; Granica, K.; Schardt, M.

    2013-05-01

    Forests play a key role in the European economy and environment. This role incorporates ecological functions which can be affected by the occurrence of insect infestations, forest fire, heavy snowfall or windfall events. Local or Regional Authorities (LRAs) thus require detailed information on the degradation status of their forests to be able to take appropriate measures for their forest management plans. In the EUFODOS project, state-of-the-art satellite and laser scanning technologies are used to provide forest authorities with cost-effective and comprehensive information on forest structure and damage. One of the six test sites is located in the Austrian province of Styria where regional forest authorities have expressed a strong need for detailed forest parameters in protective forest. As airborne laser-scanning data is available, it will be utilized to derive detailed forest parameters such as the upper forest border line, tree height, growth classes, forest density, vertical structure or volume. At the current project status, the results of (i) the forest border line, (ii) the segmentation of forest stands and (iii) the tree top detection are available and presented including accuracy assessment and interim results are shown for timber volume estimations. The final results show that the forest border can be mapped operationally with an overall accuracy of almost 99% from LiDAR data. For the segmentation of forest stands, a comparison of the automatically derived result with visual-manual delineation showed in general a more detailed segmentation result, but for all visual-manual segments a congruence of 87% within a 4 m buffer. Tree top detections were compared to stem numbers estimated based on angle-count samplings in a field campaign, which led to a correlation coefficient (R) of 0.79.

  12. EUFODOS: European Forest Downstream Services – Improved Information on Forest Structure and Damage

    Directory of Open Access Journals (Sweden)

    M. Hirschmugl

    2013-05-01

    Full Text Available Forests play a key role in the European economy and environment. This role incorporates ecological functions which can be affected by the occurrence of insect infestations, forest fire, heavy snowfall or windfall events. Local or Regional Authorities (LRAs thus require detailed information on the degradation status of their forests to be able to take appropriate measures for their forest management plans. In the EUFODOS project, state-of-the-art satellite and laser scanning technologies are used to provide forest authorities with cost-effective and comprehensive information on forest structure and damage. One of the six test sites is located in the Austrian province of Styria where regional forest authorities have expressed a strong need for detailed forest parameters in protective forest. As airborne laser-scanning data is available, it will be utilized to derive detailed forest parameters such as the upper forest border line, tree height, growth classes, forest density, vertical structure or volume. At the current project status, the results of (i the forest border line, (ii the segmentation of forest stands and (iii the tree top detection are available and presented including accuracy assessment and interim results are shown for timber volume estimations. The final results show that the forest border can be mapped operationally with an overall accuracy of almost 99% from LiDAR data. For the segmentation of forest stands, a comparison of the automatically derived result with visual-manual delineation showed in general a more detailed segmentation result, but for all visual-manual segments a congruence of 87% within a 4 m buffer. Tree top detections were compared to stem numbers estimated based on angle-count samplings in a field campaign, which led to a correlation coefficient (R of 0.79.

  13. Mechanisms of nitrogen deposition effects on temperate forest lichens and trees

    Science.gov (United States)

    Carter, Therese S.; Clark, Christopher M.; Fenn, Mark E.; Jovan, Sarah E.; Perakis, Steven; Riddell, Jennifer; Schaberg, Paul G.; Greaver, Tara; Hastings, Meredith

    2017-01-01

    We review the mechanisms of deleterious nitrogen (N) deposition impacts on temperate forests, with a particular focus on trees and lichens. Elevated anthropogenic N deposition to forests has varied effects on individual organisms depending on characteristics both of the N inputs (form, timing, amount) and of the organisms (ecology, physiology) involved. Improved mechanistic knowledge of these effects can aid in developing robust predictions of how organisms respond to either increases or decreases in N deposition. Rising N levels affect forests in micro- and macroscopic ways from physiological responses at the cellular, tissue, and organism levels to influencing individual species and entire communities and ecosystems. A synthesis of these processes forms the basis for the overarching themes of this paper, which focuses on N effects at different levels of biological organization in temperate forests. For lichens, the mechanisms of direct effects of N are relatively well known at cellular, organismal, and community levels, though interactions of N with other stressors merit further research. For trees, effects of N deposition are better understood for N as an acidifying agent than as a nutrient; in both cases, the impacts can reflect direct effects on short time scales and indirect effects mediated through long-term soil and belowground changes. There are many gaps on fundamental N use and cycling in ecosystems, and we highlight the most critical gaps for understanding potential deleterious effects of N deposition. For lichens, these gaps include both how N affects specific metabolic pathways and how N is metabolized. For trees, these gaps include understanding the direct effects of N deposition onto forest canopies, the sensitivity of different tree species and mycorrhizal symbionts to N, the influence of soil properties, and the reversibility of N and acidification effects on plants and soils. Continued study of how these N response mechanisms interact with one

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

    International Nuclear Information System (INIS)

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

    2011-01-01

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

  15. Potential climate change effects on Loblolly pine forest productivity and drainage across the Southern United States

    Energy Technology Data Exchange (ETDEWEB)

    McNulty, S.G. [USDA Forest Service, Raleigh, NC (United States). Integrated Impacts Program; Vose, J.M.; Swank, W.T. [USDA Forest Service, Otto, NC (United States). Coweeta Hydrologic Lab.

    1996-11-01

    PnET-IIS, a well validated, physiologically based, forest ecosystem model combined soil and vegetation data with six climate change scenarios. The model predicted annual net primary productivity and drainage on Loblolly pine sites in the southern US states of Texas, Mississippi, Florida and Virginia. Climate scenario air temperature changes were +2 deg C to +7 deg C >historic (1951 to 1984) values and climate scenario precipitation changes were -10% to +20% > historic values. Across the sites, increasing air temperature would have much greater impact on pine forest hydrology and productivity than would changes in precipitation. These changes could seriously impact the structure and function of southern United States forests by decreasing net primary productivity and total leaf area. Water use per unit area would increase, but total plant water demand would decrease because of reduced total leaf area, thus increasing regional pine forest drainage. An average annual air temperature increase of 7 deg C, caused a considerable reduction in the Loblolly pine range. 24 refs

  16. Effects of nitrogen deposition on carbon sequestration in Chinese fir forest ecosystems.

    Science.gov (United States)

    Wei, Xiaohua; Blanco, Juan A; Jiang, Hong; Kimmins, J P Hamish

    2012-02-01

    Nitrogen deposition and its ecological effects on forest ecosystems have received global attention. We used the ecosystem model FORECAST to assess the effects of nitrogen deposition on carbon sequestration in Chinese fir planted forests in SE China. This topic is important as China is intensifying its reforestation efforts to increase forest carbon sequestration for combating climate change impacts, using Chinese fir as the most important plantation species. A series of scenarios including seven N deposition levels (1, 5, 10, 20, 30, 40 and 50kg ha(-1)y(-1)), three management regime (rotation lengths of 15, 30 and 50 years) and two site qualities (nutrient poor and fertile sites) were defined for the simulations. Our results showed that N deposition increased carbon sequestration in Chinese fir forests, but the efficiency of the increasing effect is reduced as N deposition levels increase. When N deposition levels exceeded 20-30kg ha(-1)y(-1), the incremental effects of N deposition on forest C pools were marginal. This suggests that N deposition levels above 20-30kg ha(-1)y(-1) could lead to N saturation in Chinese fir forest soils. Any additional amounts of N input from deposition would likely be leached out. Total above-ground C was more sensitive to N deposition than to rotation length and site quality. It was also estimated that the contributions of N deposition to C sequestration in all Chinese fir forests in South-East China are 7.4×10(6)MgCy(-1) under the current N deposition levels (5 to 10kg ha(-1)y(-1)) and could reach up to 16×10(6)MgCy(-1) if N deposition continues increasing and reaches levels of 7.5 to 15kg N ha(-1)y(-1). Copyright © 2011 Elsevier B.V. All rights reserved.

  17. Recent advances towards an integrated assessment of wildfire effects in forest plantations in Portugal

    Science.gov (United States)

    Keizer, Jan Jacob; Abrantes, Nelson; Nunes, João Pedro; Caetano, Ana; Campos, Isabel; Faria, Silvia; Gonzaléz-Pelayo, Oscar; Hoogerwerf, Annelou; Malvar, Maruxa; Martins, Martinho; Methorst, Michael; Oliveira, Bruna; Prats, Sergio; Puga, João; Ré, Ana; Silva, Flávio; Serpa, Dalila; Varela, Marifé; Verheijen, Frank; Vieira, Diana

    2017-04-01

    sediment losses but also for organic matter/carbon losses, nutrient losses and pollutant export (PAHs and metals). Arguably, however, the most relevant advances that the esp team has been making in the past few years concern the following three topics: (i) the evolution of PAH and metal contents of ash and topsoil layers with time-since-fire (Campos et al., 2016); (ii) the eco-toxicological effects of post-fire runoff on aquatic organisms, especially through in-situ assays (Ré at al., 2017); (iii) mid-term effects of forest residue mulching on soil (fertility) losses as well as vegetation and soil physical, chemical and biological properties (Campos et al., 2016; Prats et al., 2016, Puga et al., in press) . Besides these three topics, the present presentation will address one topic of very recent nature (since summer 2016) and one topic of future work (from summer 2017 onwards), i.e. (iv) pre- vs. post-fire catchment behaviour and (v) post-fire carbon fluxes at the point to field scale, respectively. References Campos I., Abrantes N., Keizer J.J., Vale C., Pereira P., 2016. Major and trace elements in soils and ashes of eucalypt and pine forest plantations in Portugal following a wildfire. Science of the Total Environment 572, 1363-1376 Nunes J.P, Malvar M., Benali A.A., Rial M.E.R., Keizer J.J., 2016. A simple water balance model adapted for soil water repellency: application on Portuguese burned and unburned eucalypt stands. Hydrological Processes 30, 463-478. Nunes J.P, Vieira D., Keizer J.J., 2016. Comparing simple and complex approaches to simulate the impacts of soil water repellency on runoff and erosion in burnt Mediterranean forest slopes. EGU2017, session SSS2.22/HS9.12/NH9.24. Prats S.A., Wagenbrenner J., Malvar MC., Martins MAS., Keizer JJ., 2016. Mid-term effectiveness of mulching-based treatments in central Portugal. Science of the Total Environment 573, 1242-1254. Puga J.R.L., Abrantes N.J.C., de Oliveira M.J.S., Vieira D.C.S., Faria S.R., Gonçalves F

  18. Effect of species composition on carbon and nitrogen stocks in forest floor and mineral soil in Norway spruce and European beech mixed forests

    Science.gov (United States)

    Andivia, Enrique; Rolo, Víctor; Jonard, Mathieu; Formánek, Pavel; Ponette, Quentin

    2015-04-01

    Management of existing forests has been identified as the main strategy to enhance carbon sequestration and to mitigate the impact of climate change on forest ecosystems. In this direction, the conversion of Norway spruce monospecific stands into mixed stands by intermingling individuals of European beech is an ongoing trend in adaptive forest management strategies, especially in Central Europe. However, studies assessing the effect of changes in tree species composition on soil organic carbon (SOC) and nitrogen stocks are still scarce and there is a lack of scientific evidence supporting tree species selection as a feasible management option to mitigate the effects of predicted future climatic scenarios. We compared C and N stocks in the forest floor (litter and humus) and the top 10 cm of mineral soil in two monospecific stands of Norway spruce and European beech and in a mixed stand of both species. The effect of tree species composition on the C and N stocks and its spatial distribution was evaluated based on litterfall, root production, elevation and canopy opening, and by using a combination of modelling and geostatistical techniques. C stock was highest in the Norway spruce and the mixed stands, while N stock was highest in the mixed stand and lowest under European beech, with intermediate values in the Norway spruce stand. Each forest type showed differences in forest floor properties, suggesting that species composition is an important factor governing forest floor characteristics, including C and N stocks. The distribution of C and N stocks between forest soil layers was different for each forest type. C and N stocks were highest in the hummus layer under Norway spruce, whereas both stocks were lowest in the European beech stand. On the other hand, the mixed stand showed the highest C and N accumulation in the uppermost mineral soil layer, while the monospecific stands showed similar values. Litterfall was the main contribution to C and N stocks of the

  19. Effect of dislocations of forest on relaxation of mechanical stresses in irradiated zinc crystals

    International Nuclear Information System (INIS)

    Troitskij, O.A.; Kalymbetov, P.U.; Kusainov, S.G.; Shambulov, N.B.

    1988-01-01

    Effect of forest dislocations on the value of electron-plastic effect (EPE) in zinc crystals during their irradiation by accelerated electron packets is investigated. The following mechanical parameters are determined experimentally: total relaxation of voltages Δσ for 180s; change in reforming voltage Δσpl in single pulses of irradiation on the slope and bottom of relaxation curves. The results obtained testify to the effectiveness of forest dislocations as surmountable obstacles for the dislocations shiding in the basis plane

  20. Differential Effect of Solution Conditions on the Conformation of the Actinoporins Sticholysin II and Equinatoxin II

    Directory of Open Access Journals (Sweden)

    EDSON V.F. FAUTH

    2014-12-01

    Full Text Available Actinoporins are a family of pore-forming proteins with hemolytic activity. The structural basis for such activity appears to depend on their correct folding. Such folding encompasses a phosphocholine binding site, a tryptophan-rich region and the activity-related N-terminus segment. Additionally, different solution conditions are known to be able to influence the pore formation by actinoporins, as for Sticholysin II (StnII and Equinatoxin II (EqtxII. In this context, the current work intends to characterize the influence of distinct solution conditions in the conformational behavior of these proteins through molecular dynamics (MD simulations. The obtained data offer structural insights into actinoporins dynamics in solution, characterizing its conformational behavior at the atomic level, in accordance with previous experimental data on StnII and EqtxII hemolytic activities.

  1. Modeling of biomass smoke injection into the lower stratosphere by a large forest fire (Part II: sensitivity studies

    Directory of Open Access Journals (Sweden)

    G. Luderer

    2006-01-01

    Full Text Available The Chisholm forest fire that burned in Alberta, Canada, in May 2001 resulted in injection of substantial amounts of smoke into the lower stratosphere. We used the cloud-resolving plume model ATHAM (Active Tracer High resolution Atmospheric Model to investigate the importance of different contributing factors to the severe intensification of the convection induced by the Chisholm fire and the subsequent injection of biomass smoke into the lower stratosphere. The simulations show strong sensitivity of the pyro-convection to background meteorology. This explains the observed coincidence of the convective blow-up of the fire plume and the passage of a synoptic cold front. Furthermore, we performed model sensitivity studies to the rate of release of sensible heat and water vapor from the fire. The release of sensible heat by the fire plays a dominant role for the dynamic development of the pyro-cumulonimbus cloud (pyroCb and the height to which smoke is transported. The convection is very sensitive to the heat flux from the fire. The emissions of water vapor play a less significant role for the injection height but enhance the amount of smoke transported beyond the tropopause level. The aerosol burden in the plume has a strong impact on the microphysical structure of the resulting convective cloud. The dynamic evolution of the pyroCb, however, is only weakly sensitive to the abundance of cloud condensation nuclei (CCN from the fire. In contrast to previous findings by other studies of convective clouds, we found that fire CCN have a negative effect on the convection dynamics because they give rise to a delay in the freezing of cloud droplets. Even in a simulation without fire CCN, there is no precipitation formation within the updraft region of the pyroCb. Enhancement of convection by aerosols as reported from studies of other cases of convection is therefore not found in our study.

  2. Stream II-V5: Revision Of Stream II-V4 To Account For The Effects Of Rainfall Events

    International Nuclear Information System (INIS)

    Chen, K.

    2010-01-01

    STREAM II-V4 is the aqueous transport module currently used by the Savannah River Site emergency response Weather Information Display (WIND) system. The transport model of the Water Quality Analysis Simulation Program (WASP) was used by STREAM II to perform contaminant transport calculations. WASP5 is a US Environmental Protection Agency (EPA) water quality analysis program that simulates contaminant transport and fate through surface water. STREAM II-V4 predicts peak concentration and peak concentration arrival time at downstream locations for releases from the SRS facilities to the Savannah River. The input flows for STREAM II-V4 are derived from the historical flow records measured by the United States Geological Survey (USGS). The stream flow for STREAM II-V4 is fixed and the flow only varies with the month in which the releases are taking place. Therefore, the effects of flow surge due to a severe storm are not accounted for by STREAM II-V4. STREAM II-V4 has been revised to account for the effects of a storm event. The steps used in this method are: (1) generate rainfall hyetographs as a function of total rainfall in inches (or millimeters) and rainfall duration in hours; (2) generate watershed runoff flow based on the rainfall hyetographs from step 1; (3) calculate the variation of stream segment volume (cross section) as a function of flow from step 2; (4) implement the results from steps 2 and 3 into the STREAM II model. The revised model (STREAM II-V5) will find the proper stream inlet flow based on the total rainfall and rainfall duration as input by the user. STREAM II-V5 adjusts the stream segment volumes (cross sections) based on the stream inlet flow. The rainfall based stream flow and the adjusted stream segment volumes are then used for contaminant transport calculations.

  3. Detecting the effects of hydrocarbon pollution in the Amazon forest using hyperspectral satellite images

    International Nuclear Information System (INIS)

    Arellano, Paul; Tansey, Kevin; Balzter, Heiko; Boyd, Doreen S.

    2015-01-01

    The global demand for fossil energy is triggering oil exploration and production projects in remote areas of the world. During the last few decades hydrocarbon production has caused pollution in the Amazon forest inflicting considerable environmental impact. Until now it is not clear how hydrocarbon pollution affects the health of the tropical forest flora. During a field campaign in polluted and pristine forest, more than 1100 leaf samples were collected and analysed for biophysical and biochemical parameters. The results revealed that tropical forests exposed to hydrocarbon pollution show reduced levels of chlorophyll content, higher levels of foliar water content and leaf structural changes. In order to map this impact over wider geographical areas, vegetation indices were applied to hyperspectral Hyperion satellite imagery. Three vegetation indices (SR, NDVI and NDVI 705 ) were found to be the most appropriate indices to detect the effects of petroleum pollution in the Amazon forest. - Highlights: • Leaf biochemical alterations in the rainforest are caused by petroleum pollution. • Lower levels of chlorophyll content are symptom of vegetation stress in polluted sites. • Increased foliar water content was found in vegetation near polluted sites. • Vegetation stress was detected by using vegetation indices from satellite images. • Polluted sites and hydrocarbon seepages in rainforest can be identified from space. - Hydrocarbon pollution in the Amazon forest is observed for first time from satellite data

  4. Positive effects of radiation on forest production; Efectos positivos de la radiacion sobre la produccion forestal

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez J, J.; De la Cruz O, A.; Aguilar, M. A.; Caxnajoy, P. A.; Salceda S, V. [ININ, Departamento de Biologia, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)], e-mail: josefina.gonzalez@inin.gob.mx

    2009-10-15

    The deforestation is a world problem and due to of increment of seed demand and seedling of good quality, was realized a work about the production improvement on commercial or forest trees for the Mexico State. It was combined the use of two techniques: the plant tissue culture and ionizing application. It was utilized seed of Pinus hartwegii collected and valued previously by ProBosque, with them were formed homogeneous lots that were irradiated to dose of 0, 30, 45, 60, 75, 90 and 105 Gy into irradiator Gammacel-220 and later were decontaminated and cultivated in vitro. The seeds-planting were placed in a growth room with temperature and controlled light. After 10 cultivation days was obtained germination among 87-100% without observing the induction of negative changes in none of treatments. After 21 days already developed the embryos completely, modifications were presented in some structures. With these was possible to determine the lethal dose mean that oscillates between 100 and 105 Gy; since to dose bigger than 100 Gy more of 75% of individuals or seedlings present the phenols formation inducing the material lost by oxidation starting from day 32. Also, it is observed that applied doses between the 30 and 90 Gy do not affect or modify the embryogenesis in Pinus hartwegii but if the structures formation and seedling size since after 12 development days it is possible to appreciate to dose of 90, 75 and 45 Gy the presence of a primary radicular system, same that is observed after 22 development days in the witness. Another observation was that to dose of 45 and 90 Gy the leafs presents bigger elongation increasing the seedlings size on 22% in comparison with the witness. We can say that the doses understood between 45 and 90 Gy affect in a positive way the hormonal production of Pinus hartwegii seedlings and that the dose of 90 Gy accelerates the rhizogenes process and it increases the seedling size allowing to diminish the production time of Pinus hartwegii

  5. On the use of a simple deciduous forest model for the interpretation of climate change effects at the level of carbon dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Veroustraete, F. (Flemish Inst. for Technological Research, Boeretang, Mol (Belgium))

    1994-09-01

    In this publication an approach is described to model the Net Carbon Exchange (NCE) between the vegetated surface-atmosphere interface of a deciduous forest. In that context it is not only important to simulate effects of climatology (temperature, CO[sub 2]) on forest evolution, but also to evaluate its NCE. For climatological conditions representative for the mid latitudes the influences of changes in atmospheric temperature and CO[sub 2] levels are simulated. Four compartments are defined in the model, two compartments simulating phytomass functional elements with large temporal biomass fluctuations (green compartment) and phytomass temporal fluctuations that are relatively small (non-green compartment). The litter compartment is also incorporated in the model and its fluxes evaluated. Model runs were executed for two CO[sub 2] scenarios and a climatological record reconstructed for the period covering 1833 till 1989 at a latitude and longitude of 51[sup o]N, 2.5[sup o]E. It has to be remarked that the addition of 4.5[sup o]C to a climatological record for all seasons is a simplification when simulating the effects of a temperature rise. The model outcome however suggests that the CO[sub 2] mixing ratio rate increase after World War II (WW II) has induced a phytomass increase in young forests. The constraints of the model and its application in Remote Sensing-derived data sets are discussed

  6. Threshold effect of habitat loss on bat richness in cerrado-forest landscapes.

    Science.gov (United States)

    Muylaert, Renata L; Stevens, Richard D; Ribeiro, Milton C

    2016-09-01

    Understanding how animal groups respond to contemporary habitat loss and fragmentation is essential for development of strategies for species conservation. Until now, there has been no consensus about how landscape degradation affects the diversity and distribution of Neotropical bats. Some studies demonstrate population declines and species loss in impacted areas, although the magnitude and generality of these effects on bat community structure are unclear. Empirical fragmentation thresholds predict an accentuated drop in biodiversity, and species richness in particular, when less than 30% of the original amount of habitat in the landscape remains. In this study, we tested whether bat species richness demonstrates this threshold response, based on 48 sites distributed across 12 landscapes with 9-88% remaining forest in Brazilian cerrado-forest formations. We also examined the degree to which abundance was similarly affected within four different feeding guilds. The threshold value for richness, below which bat diversity declines precipitously, was estimated at 47% of remaining forest. To verify if the response of bat abundance to habitat loss differed among feeding guilds, we used a model selection approach based on Akaike's information criterion. Models accounted for the amount of riparian forest, semideciduous forest, cerrado, tree plantations, secondary forest, and the total amount of forest in the landscape. We demonstrate a nonlinear effect of the contribution of tree plantations to frugivores, and a positive effect of the amount of cerrado to nectarivores and animalivores, the groups that responded most to decreases in amount of forest. We suggest that bat assemblages in interior Atlantic Forest and cerrado regions of southeastern Brazil are impoverished, since we found lower richness and abundance of different groups in landscapes with lower amounts of forest. The relatively higher threshold value of 47% suggests that bat communities have a relatively lower

  7. Modeling the CO2-effects of forest management and wood usage on a regional basis.

    Science.gov (United States)

    Knauf, Marcus; Köhl, Michael; Mues, Volker; Olschofsky, Konstantin; Frühwald, Arno

    2015-12-01

    At the 15 th Conference of Parties of the UN Framework Convention on Climate Change, Copenhagen, 2009, harvested wood products were identified as an additional carbon pool. This modification eliminates inconsistencies in greenhouse gas reporting by recognizing the role of the forest and timber sector in the global carbon cycle. Any additional CO 2 -effects related to wood usage are not considered by this modification. This results in a downward bias when the contribution of the forest and timber sector to climate change mitigation is assessed. The following article analyses the overall contribution to climate protection made by the forest management and wood utilization through CO 2 -emissions reduction using an example from the German state of North Rhine-Westphalia. Based on long term study periods (2011 to 2050 and 2100, respectively). Various alternative scenarios for forest management and wood usage are presented. In the mid- to long-term (2050 and 2100, respectively) the net climate protection function of scenarios with varying levels of wood usage is higher than in scenarios without any wood usage. This is not observed for all scenarios on short and mid term evaluations. The advantages of wood usage are evident although the simulations resulted in high values for forest storage in the C pools. Even the carbon sink effect due to temporal accumulation of deadwood during the period from 2011 to 2100 is outbalanced by the potential of wood usage effects. A full assessment of the CO 2 -effects of the forest management requires an assessment of the forest supplemented with an assessment of the effects of wood usage. CO 2 -emission reductions through both fuel and material substitution as well as CO 2 sink in wood products need to be considered. An integrated assessment of the climate protection function based on the analysis of the study's scenarios provides decision parameters for a strategic approach to climate protection with regard to forest management and

  8. Spatial and temporal trends of drought effects in a heterogeneous semi-arid forest ecosystem

    Science.gov (United States)

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

    2016-01-01

    Drought has long been recognized as a driving mechanism in the forests of western North America and drought-induced mortality has been documented across genera in recent years. Given the frequency of these events are expected to increase in the future, understanding patterns of mortality and plant response to severe drought is important to resource managers. Drought can affect the functional, physiological, structural, and demographic properties of forest ecosystems. Remote sensing studies have documented changes in forest properties due to direct and indirect effects of drought; however, few studies have addressed this at local scales needed to characterize highly heterogeneous ecosystems in the forest-shrubland ecotone. We analyzed a 22-year Landsat time series (1985–2012) to determine changes in forest in an area that experienced a relatively dry decade punctuated by two years of extreme drought. We assessed the relationship between several vegetation indices and field measured characteristics (e.g. plant area index and canopy gap fraction) and applied these indices to trend analysis to uncover the location, direction and timing of change. Finally, we assessed the interaction of climate and topography by forest functional type. The Normalized Difference Moisture Index (NDMI), a measure of canopy water content, had the strongest correlation with short-term field measures of plant area index (R2 = 0.64) and canopy gap fraction (R2 = 0.65). Over the entire time period, 25% of the forested area experienced a significant (p-value trend in NDMI, compared to less than 10% in a positive trend. Coniferous forests were more likely to be associated with a negative NDMI trend than deciduous forest. Forests on southern aspects were least likely to exhibit a negative trend while north aspects were most prevalent. Field plots with a negative trend had a lower live density, and higher amounts of standing dead and down trees compared to plots with no trend. Our analysis

  9. Modeling the Effects of Harvest Alternatives on Mitigating Oak Decline in a Central Hardwood Forest Landscape.

    Directory of Open Access Journals (Sweden)

    Wen J Wang

    Full Text Available Oak decline is a process induced by complex interactions of predisposing factors, inciting factors, and contributing factors operating at tree, stand, and landscape scales. It has greatly altered species composition and stand structure in affected areas. Thinning, clearcutting, and group selection are widely adopted harvest alternatives for reducing forest vulnerability to oak decline by removing susceptible species and declining trees. However, the long-term, landscape-scale effects of these different harvest alternatives are not well studied because of the limited availability of experimental data. In this study, we applied a forest landscape model in combination with field studies to evaluate the effects of the three harvest alternatives on mitigating oak decline in a Central Hardwood Forest landscape. Results showed that the potential oak decline in high risk sites decreased strongly in the next five decades irrespective of harvest alternatives. This is because oak decline is a natural process and forest succession (e.g., high tree mortality resulting from intense competition would eventually lead to the decrease in oak decline in this area. However, forest harvesting did play a role in mitigating oak decline and the effectiveness varied among the three harvest alternatives. The group selection and clearcutting alternatives were most effective in mitigating oak decline in the short and medium terms, respectively. The long-term effects of the three harvest alternatives on mitigating oak decline became less discernible as the role of succession increased. The thinning alternative had the highest biomass retention over time, followed by the group selection and clearcutting alternatives. The group selection alternative that balanced treatment effects and retaining biomass was the most viable alternative for managing oak decline. Insights from this study may be useful in developing effective and informed forest harvesting plans for managing oak

  10. A pantropical assessment of vertebrate physical damage to forest seedlings and the effects of defaunation

    Directory of Open Access Journals (Sweden)

    Cooper Rosin

    2017-07-01

    Full Text Available Many of the forces that shape tropical forest plant communities are facilitated by interactions with animals, which can either promote or inhibit plant reproduction and survival across ontogenetic stages. Hunting-induced defaunation can disrupt these interactions, altering tree recruitment, forest structure, and carbon storage, with strong effects at the seed and seedling stages. Research to date has largely focused on how changes to prominent interactions (especially seed dispersal affect plant species and communities, while concurrent disruptions to less-studied processes may have opposing effects. With a particularly limited understanding of non-trophic interactions – such as physical damage to seedlings by vertebrate trampling, rooting, and digging – it remains difficult to predict the outcomes of defaunation for tropical forest plant communities. We established 1800 artificial seedlings in 18 intact and disturbed sites across the three main tropical forest regions – the Neotropics (Peru, the Afrotropics (Gabon and the Indo-Malayan tropics (Malaysian Borneo – to isolate non-trophic vertebrate physical damage from other causes of seedling mortality (herbivory, pathogens, abiotic desiccation, etc., and to understand its effects in intact and anthropogenically-disturbed forests. We found that vertebrate physical damage is a consistent force in forests across the tropics, and that hunting significantly alters its strength, with a ∼70% decrease in damage in hunted vs. intact sites that resulted in a ∼3.5-fold (350% increase in artificial seedling survival. Our results reveal an understudied mechanism that may contribute to changes in seedling survival, stem density, and plant community composition in tropical forests subjected to hunting.

  11. Barrier effects on vertebrate distribution caused by a motorway crossing through fragmented forest landscape

    Directory of Open Access Journals (Sweden)

    Tellería, J. L.

    2011-12-01

    Full Text Available We analysed the effects of a 25–year–old motorway on the distribution of five vertebrates inhabiting a fragmented forest landscape and differing in their ability to move across linear infrastructures. We found clear evidence of barrier effects on the distribution of the forest lizard Psammodromus algirus. The roe deer (Capreolus capreolus was also unequally distributed on both sides of the motorway, but this could also be due, at least in part, to fragmentation. The eyed lizard (Timon lepidus, that can move through open fields, showed no evidence of barrier effects. The distribution of two small birds (Erithacus rubecula and Phylloscopus bonelli was unaffected by the motorway. Our results show that a motorway may severely restrict the distribution of species which can withstand high levels of forest fragmentation but show limited dispersal ability, highlighting the role of linear infrastructures in shaping species’ ranges at regional scales.

  12. Pre-outbreak forest conditions mediate the effects of spruce beetle outbreaks on fuels in subalpine forests of Colorado.

    Science.gov (United States)

    Mietkiewicz, Nathan; Kulakowski, Dominik; Veblen, Thomas T

    2018-03-01

    Over the past 30 years, forest disturbances have increased in size, intensity, and frequency globally, and are predicted to continue increasing due to climate change, potentially relaxing the constraints of vegetation properties on disturbance regimes. However, the consequences of the potentially declining importance of vegetation in determining future disturbance regimes are not well understood. Historically, bark beetles preferentially attack older trees and stands in later stages of development. However, as climate warming intensifies outbreaks by promoting growth of beetle populations and compromising tree defenses, smaller diameter trees and stands in early stages of development now are being affected by outbreaks. To date, no study has considered how stand age and other pre-outbreak forest conditions mediate the effects of outbreaks on surface and aerial fuel arrangements. We collected fuels data across a chronosequence of post-outbreak sites affected by spruce beetle (SB) between the 1940s and the 2010s, stratified by young (130 yr) post-fire stands. Canopy and surface fuel loads were calculated for each tree and stand, and available crown fuel load, crown bulk density, and canopy bulk densities were estimated. Canopy bulk density and density of live canopy individuals were reduced in all stands affected by SB, though foliage loss was proportionally greater in old stands as compared to young stands. Fine surface fuel loads in young stands were three times greater shortly (fuels decreased to below endemic (i.e., non-outbreak) levels. In both young and old stands, the net effect of SB outbreaks during the 20th and 21st centuries reduced total canopy fuels and increased stand-scale spatial heterogeneity of canopy fuels following outbreak. Importantly, the decrease in canopy fuels following outbreaks was greater in young post-fire stands than in older stands, suggesting that SB outbreaks may more substantially reduce risk of active crown fire when they affect

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

    Science.gov (United States)

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

    2016-01-01

    The Fukushima Daiichi nuclear power plant disaster caused serious radiocesium (137Cs) contamination of forest ecosystems over a wide area. Forest-floor organic layers play a key role in controlling the overall bioavailability of 137Cs in forest ecosystems; however, there is still an insufficient understanding of how forest types influence the retention capability of 137Cs in organic layers in Japanese forest ecosystems. Here we conducted plot-scale investigations on the retention of 137Cs in organic layers at two contrasting forest sites in Fukushima. In a deciduous broad-leaved forest, approximately 80% of the deposited 137Cs migrated to mineral soil located below the organic layers within two years after the accident, with an ecological half-life of approximately one year. Conversely, in an evergreen coniferous forest, more than half of the deposited 137Cs remained in the organic layers, with an ecological half-life of 2.1 years. The observed retention behavior can be well explained by the tree phenology and accumulation of 137Cs associated with litter materials with different degrees of degradation in the organic layers. Spatial and temporal patterns of gamma-ray dose rates depended on the retention capability. Our results demonstrate that enhanced radiation risks last longer in evergreen coniferous forests than in deciduous broad-leaved forests. PMID:27974832

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

    Science.gov (United States)

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

    2016-12-01

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

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

    Science.gov (United States)

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

    2008-01-01

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

  16. Effect of acid deposition on Nanshan forest at Chongging in China

    International Nuclear Information System (INIS)

    Xu Xiaolei; Ogura, Norio

    1992-01-01

    Chongqing is the city where atmospheric pollution is severest in China, and the pH of rainwater has been measured every year since 1981, which is close to 4.0 now. In 1982, the decline of Pinus massoniana in Nanshan district in southeast Chongqing has occurred. The decline phenomena of this forest attracted attention also in foreign countries, and the various studies on its causes have been carried out, consequently, the main cause was presumed to be the compound effect of acid rain, acid mist and the damage by insects. It was clarified by the recent research that the dry and wet acid fallouts mainly composed of SO 2 are one of the important causes that brought about the decline of Pinus massoniana in Nanshan. The forest area in Nanshan is about 2000 ha, and almost the simple forest of Pinus massoniana that distributes at the elevation from 400 to 1400 m. The withering of a small number began to occur in 1982, but thereafter, the area of withering increased rapidly, and reached 41.8% of the total forest area in July, 1983. The decline still continues now. The direct effect of acid fallout to Nanshan forest and the indirect effect through soil are reported in this paper. (K.I.)

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

    Science.gov (United States)

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

    1982-01-01

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

  18. Enhancing Tools and Geospatial Data to Support Operational Forest Management and Regional Forest Planning in the Face of Climate Change

    Science.gov (United States)

    Falkowski, M. J.; Fekety, P.; Hudak, A. T.; Kayastha, N.; Nagel, L. M.

    2014-12-01

    A detailed understanding of how forest composition, structure, and function will be impacted by projected climate change and related adaptive forest management activities are particularly lacking at local scales, where on-the-ground management activities are implemented. Climate sensitive forest dynamics models may prove to be effective tools for developing a comprehensive understanding. However, to be applicable to both regional forest planning and operational forest management, modeling approaches must be capable of simulating forest dynamics across large spatial extents (required for regional planning) while maintaining a high-level of spatial detail (required for operational management). LiDAR remote sensing has shown great utility for operational forest inventory and management, including forest dynamics modeling, albeit across relatively small spatial extents. We present a remote sensing driven approach to spatially initialize a climate-sensitive forest dynamics model (LANDIS-II) in the Pacific Northwest of the US via an integration of airborne LiDAR data with satellite remote sensing data. The system provides detailed forest inventory information - at the landscape level - that is subsequently employed to demonstrate how such models can be used to 1) investigate the potential impacts of climate change on future forest composition and structure, and 2) assess how various forest management practices may either enhance or degrade forest resilience to changing climate and disturbance regimes.

  19. Effects of Increased Nitrogen Availability on C and N Cycles in Tropical Forests: A Meta-Analysis.

    Science.gov (United States)

    Bejarano-Castillo, Marylin; Campo, Julio; Roa-Fuentes, Lilia L

    2015-01-01

    Atmospheric N deposition is predicted to increase four times over its current status in tropical forests by 2030. Our ability to understand the effects of N enrichment on C and N cycles is being challenged by the large heterogeneity of the tropical forest biome. The specific response will depend on the forest's nutrient status; however, few studies of N addition appear to incorporate the nutrient status in tropical forests, possibly due to difficulties in explaining how this status is maintained. We used a meta-analysis to explore the consequences of the N enrichment on C and N cycles in tropical montane and lowland forests. We tracked changes in aboveground and belowground plant C and N and in mineral soil in response to N addition. We found an increasing trend of plant biomass in montane forests, but not in lowland forests, as well as a greater increase in NO emission in montane forest compared with lowland forest. The N2O and NO emission increase in both forest; however, the N2O increase in lowland forest was significantly even at first time N addition. The NO emission increase showed be greater at first term compared with long term N addition. Moreover, the increase in total soil N, ammonium, microbial N, and dissolved N concentration under N enrichment indicates a rich N status of lowland forests. The available evidence of N addition experiments shows that the lowland forest is richer in N than montane forests. Finally, the greater increase in N leaching and N gas emission highlights the importance of study the N deposition effect on the global climate change.

  20. Overstory structure and soil nutrients effect on plant diversity in unmanaged moist tropical forest

    Science.gov (United States)

    Gautam, Mukesh Kumar; Manhas, Rajesh Kumar; Tripathi, Ashutosh Kumar

    2016-08-01

    Forests with intensive management past are kept unmanaged to restore diversity and ecosystem functioning. Before perpetuating abandonment after protracted restitution, understanding its effect on forest vegetation is desirable. We studied plant diversity and its relation with environmental variables and stand structure in northern Indian unmanaged tropical moist deciduous forest. We hypothesized that post-abandonment species richness would have increased, and the structure of contemporary forest would be heterogeneous. Vegetation structure, composition, and diversity were recorded, in forty 0.1 ha plots selected randomly in four forest ranges. Three soil samples per 0.1 ha were assessed for physicochemistry, fine sand, and clay mineralogy. Contemporary forest had less species richness than pre-abandonment reference period. Fourteen species were recorded as either seedling or sapling, suggesting reappearance or immigration. For most species, regeneration was either absent or impaired. Ordination and multiple regression results showed that exchangeable base cations and phosphorous affected maximum tree diversity and structure variables. Significant correlations between soil moisture and temperature, and shrub layer was observed, besides tree layer correspondence with shrub richness, suggesting that dense overstory resulting from abandonment through its effect on soil conditions, is responsible for dense shrub layer. Herb layer diversity was negatively associated with tree layer and shrub overgrowth (i.e. Mallotus spp.). Protracted abandonment may not reinforce species richness and heterogeneity; perhaps result in high tree and shrub density in moist deciduous forests, which can impede immigrating or reappearing plant species establishment. This can be overcome by density/basal area reduction strategies, albeit for both tree and shrub layer.

  1. Environmental change and disease dynamics: effects of intensive forest management on Puumala hantavirus infection in boreal bank vole populations.

    Science.gov (United States)

    Voutilainen, Liina; Savola, Sakeri; Kallio, Eva Riikka; Laakkonen, Juha; Vaheri, Antti; Vapalahti, Olli; Henttonen, Heikki

    2012-01-01

    Intensive management of Fennoscandian forests has led to a mosaic of woodlands in different stages of maturity. The main rodent host of the zoonotic Puumala hantavirus (PUUV) is the bank vole (Myodes glareolus), a species that can be found in all woodlands and especially mature forests. We investigated the influence of forest age structure on PUUV infection dynamics in bank voles. Over four years, we trapped small mammals twice a year in a forest network of different succession stages in Northern Finland. Our study sites represented four forest age classes from young (4 to 30 years) to mature (over 100 years) forests. We show that PUUV-infected bank voles occurred commonly in all forest age classes, but peaked in mature forests. The probability of an individual bank vole to be PUUV infected was positively related to concurrent host population density. However, when population density was controlled for, a relatively higher infection rate was observed in voles trapped in younger forests. Furthermore, we found evidence of a "dilution effect" in that the infection probability was negatively associated with the simultaneous density of other small mammals during the breeding season. Our results suggest that younger forests created by intensive management can reduce hantaviral load in the environment, but PUUV is common in woodlands of all ages. As such, the Fennoscandian forest landscape represents a significant reservoir and source of hantaviral infection in humans.

  2. Environmental change and disease dynamics: effects of intensive forest management on Puumala hantavirus infection in boreal bank vole populations.

    Directory of Open Access Journals (Sweden)

    Liina Voutilainen

    Full Text Available Intensive management of Fennoscandian forests has led to a mosaic of woodlands in different stages of maturity. The main rodent host of the zoonotic Puumala hantavirus (PUUV is the bank vole (Myodes glareolus, a species that can be found in all woodlands and especially mature forests. We investigated the influence of forest age structure on PUUV infection dynamics in bank voles. Over four years, we trapped small mammals twice a year in a forest network of different succession stages in Northern Finland. Our study sites represented four forest age classes from young (4 to 30 years to mature (over 100 years forests. We show that PUUV-infected bank voles occurred commonly in all forest age classes, but peaked in mature forests. The probability of an individual bank vole to be PUUV infected was positively related to concurrent host population density. However, when population density was controlled for, a relatively higher infection rate was observed in voles trapped in younger forests. Furthermore, we found evidence of a "dilution effect" in that the infection probability was negatively associated with the simultaneous density of other small mammals during the breeding season. Our results suggest that younger forests created by intensive management can reduce hantaviral load in the environment, but PUUV is common in woodlands of all ages. As such, the Fennoscandian forest landscape represents a significant reservoir and source of hantaviral infection in humans.

  3. The Effectiveness of Private Forest Institutional and Policy in Banjarnegara and Banyumas Regency

    Directory of Open Access Journals (Sweden)

    Eva Fauziyah

    2017-12-01

    Full Text Available This research aimed to analyze the effectiveness of institusional and policy on private forest. The research was conducted in Banjarnegara and Banyumas Regency in August 2012 - May 2013. The methods used in this study are structured interview, open interview and Focus Group Discussion (FGD. Assessment of institutional effectiveness was done to government institutional, marketing institututional, and farmer institutional using recommended indicator namely: 1 user and resource boundaries, 2 appropriation and provision, 3 collective-choice arrangements, 4 monitoring, 5 graduated sanctions, 6 conflict-resolution mechanisms, and 7 recognition of appropriators’ rights to organize. The collected data were processed using likert scale and analyzed descriptively. The results showed that effectiveness of institutional in Kabupaten Banjarnegara and Banyumas Regency was moderate condition (quite effective. The effectiveness of private forest policy is seen from four policy viewpoints: policy accuracy, policy implementation, target accuracy, and environmental accuracy. Private forest policy in Kabupaten Banjarnegara is effective based on policy accuracy and environmental accuracy, while private forest policy in Banyumas Regency is effective based on target accuracy and environmental accuracy. This difference in assessment is due to the different of policy or program at the location according to the condition and the desire of community.

  4. Radial electrical field effects in TJ-II. (Preliminary study)

    International Nuclear Information System (INIS)

    Guasp, J.

    1996-01-01

    The influence of the radial electric field upon the neoclassical transport coefficients of TJ-II helical axis Stellarator has been calculated as well on the microwave heating stage (ECRH) as on the neutral injection one (NBI). The influence of the solutions for the self-consistent ambipolar field on confinement times and temperatures has been studied by means of a zero-dimensional energy balance. The simultaneous presence of two roots, the electronic and the ionic one, is observed for the ECRH phase, while for NBI only the ionic root appears, although with a strong field intensity that could produce a favourable effect on confinement. The interest and need of the extension of these calculations to include radial profile effects by using spatial dependent transport codes in stressed

  5. Neurological Adverse Effects after Radiation Therapy for Stage II Seminoma

    DEFF Research Database (Denmark)

    Ebbeskov Lauritsen, Liv; Meidahl Petersen, Peter; Daugaard, Gedske

    2012-01-01

    against the tumour bed) with a conventional fractionation of 2 Gy/day, 5 days per week. RT was applied as hockey-stick portals, also called L-fields. In 2 cases, the symptoms fully resolved. Therapeutic irradiation can cause significant injury to the peripheral nerves of the lumbosacral plexus and/or...... to the spinal cord. RT is believed to produce plexus injury by both direct toxic effects and secondary microinfarction of the nerves, but the exact pathophysiology of RT-induced injury is unclear. Since reported studies of radiation-induced neurological adverse effects are limited, it is difficult to estimate......We report 3 cases of patients with testicular cancer and stage II seminoma who developed neurological symptoms with bilateral leg weakness about 4 to 9 months after radiation therapy (RT). They all received RT to the para-aortic lymph nodes with a total dose of 40 Gy (36 Gy + 4 Gy as a boost...

  6. Climate effects on vegetation vitality at the treeline of boreal forests of Mongolia

    Directory of Open Access Journals (Sweden)

    M. Klinge

    2018-03-01

    Full Text Available In northern Mongolia, at the southern boundary of the Siberian boreal forest belt, the distribution of steppe and forest is generally linked to climate and topography, making this region highly sensitive to climate change and human impact. Detailed investigations on the limiting parameters of forest and steppe in different biomes provide necessary information for paleoenvironmental reconstruction and prognosis of potential landscape change. In this study, remote sensing data and gridded climate data were analyzed in order to identify main distribution patterns of forest and steppe in Mongolia and to detect environmental factors driving forest development. Forest distribution and vegetation vitality derived from the normalized differentiated vegetation index (NDVI were investigated for the three types of boreal forest present in Mongolia (taiga, subtaiga and forest–steppe, which cover a total area of 73 818 km2. In addition to the forest type areas, the analysis focused on subunits of forest and nonforested areas at the upper and lower treeline, which represent ecological borders between vegetation types. Climate and NDVI data were analyzed for a reference period of 15 years from 1999 to 2013. The presented approach for treeline delineation by identifying representative sites mostly bridges local forest disturbances like fire or tree cutting. Moreover, this procedure provides a valuable tool to distinguish the potential forested area. The upper treeline generally rises from 1800 m above sea level (a.s.l. in the northeast to 2700 m a.s.l. in the south. The lower treeline locally emerges at 1000 m a.s.l. in the northern taiga and rises southward to 2500 m a.s.l. The latitudinal gradient of both treelines turns into a longitudinal one on the eastern flank of mountain ranges due to higher aridity caused by rain-shadow effects. Less productive trees in terms of NDVI were identified at both the upper and lower treeline in relation

  7. Ionizing radiation: levels and effects. Volume II. Effects

    International Nuclear Information System (INIS)

    1972-01-01

    The genetic effects of ionizing radiation were last reviewed comprehensively by the Committee in its 1966 report (575), whereas the particular problem of the induction of chromosome aberrations by irradiation of human somatic cells was reviewed in the Committee's 1969 report (576). The present review will consider the further experimental data that have been obtained since these reports. Of the recent advances in human genetics, those concerning the occurrence and transmission of translocations have particular relevance to the problem of estimating risks, and will be discussed in the last section of this review.

  8. Perspectives regarding 50 years of research on effects of tropospheric ozone air pollution on US forests

    Energy Technology Data Exchange (ETDEWEB)

    Karnosky, David F. [School of Forest Resources and Environmental Science, Michigan Tech University, 1400 Townsend Drive, Houghton, MI 49931 (United States)]. E-mail: karnosky@mtu.edu; Skelly, John M. [5316 Wyndemere Circle, Mineral, VA 23117 (United States); Percy, Kevin E. [Natural Resources Canada, Canadian Forest Service-Atlantic Forestry Centre, PO 1350 Regent Street, Fredericton, New Brunswick, E3B 5P7 (Canada); Chappelka, Art H. [School of Forestry and Wildlife Sciences, Auburn University, 206 M. White-Smith Hall, Auburn, AL 36849-5418 (United States)

    2007-06-15

    Tropospheric ozone (O{sub 3}) was first determined to be phytotoxic to grapes in southern California in the 1950s. Investigations followed that showed O{sub 3} to be the cause of foliar symptoms on tobacco and eastern white pine. In the 1960s, 'X' disease of ponderosa pines within the San Bernardino Mountains was likewise determined to be due to O{sub 3}. Nearly 50 years of research have followed. Foliar O{sub 3} symptoms have been verified under controlled chamber conditions. Studies have demonstrated negative growth effects on forest tree seedlings due to season-long O{sub 3} exposures, but due to complex interactions within forest stands, evidence of similar losses within mature tree canopies remains elusive. Investigations on tree growth, O{sub 3} flux, and stand productivity are being conducted along natural O{sub 3} gradients and in open-air exposure systems to better understand O{sub 3} effects on forest ecosystems. Given projected trends in demographics, economic output and climate, O{sub 3} impacts on US forests will continue and are likely to increase. - Elevated tropospheric ozone remains an important phytotoxic air pollutant over large areas of US forests.

  9. A Synthesis of Sierran Forest Biomass Management Studies and Potential Effects on Water Quality

    Directory of Open Access Journals (Sweden)

    Peter J. Weisberg

    2010-09-01

    Full Text Available The Lake Tahoe basin, located along the California and Nevada border between the Carson and Sierra Nevada mountain ranges, represents a complex forested ecosystem consisting of numerous sub-watersheds and tributaries that discharge directly to Lake Tahoe. This synthesis focuses on historical and current nutrient pools and the effects of biomass management in watersheds of the basin relative to their potential impacts on nutrient (N, P related discharge water quality. An accumulating forest floor as a result of fire suppression has resulted in the build-up of large nutrient pools that now provide a “natural” source of long term nutrient availability to surface waters. As a consequence, stand and forest floor replacing wildfire may cause a large magnitude nutrient mobilization impact on runoff water quality. Hence, mechanical harvest and controlled burning have become popular management strategies. The most ecologically significant long-term effects of controlled fire appear to be the loss of C and N from the forest floor. Although the application of controlled fire may have some initial impact on overland/litter interflow nutrient loading, controlled burning in conjunction with mechanical harvest has the potential to improve runoff water quality by reducing N and P discharge and improving the overall health of forest ecosystems without the danger of a high intensity wildfire.

  10. Effects of forest structure on litter production, soil chemical composition and litter-soil interactions

    Directory of Open Access Journals (Sweden)

    Elivane Salete Capellesso

    2016-01-01

    Full Text Available ABSTRACT Litter production in forest ecosystems is a major indicator of primary productivity because litter helps incorporate carbon and nutrients from plants into the soil and is directly involved in plant-soil interactions. To our knowledge, few studies have investigated the relationship between species diversity and ecosystem processes in subtropical forest fragments. In this work, we determined forest structural parameters and assessed seasonal leaf litter input, leaf decomposition rate, litter quality and soil characteristics in two subtropical Atlantic Forest fragments. Litter production was greater in the native fragment with the higher species diversity (FN1. The two native fragments (FN1 and FN2 differed in basal area, volume and dominance in the upper stratum, which were positively correlated with litter production in FN1 but negatively correlated in FN2. Soil in FN1 exhibited higher contents of organic C, available phosphorus and exchangeable calcium, and the leaf litter had a higher C:N ratio. Although these results are consistent with a plant-soil feedback, which suggests the presence of a complementary effect, the dominance of certain families in subtropical forest fragments results in a selection effect on litter productivity and decomposition.

  11. Effect of Phosphorylation and Copper(II or Iron(II Ions Enrichment on Some Physicochemical Properties of Spelt Starch

    Directory of Open Access Journals (Sweden)

    Jacek Rożnowski

    Full Text Available ABSTRACT: This paper provides an assessment of the effect of saturation of spelt starch and monostarch phosphate with copper or iron ions on selected physicochemical properties of the resulting modified starches. Native and modified spelt starch samples were analyzed for selected mineral element content using Atomic Absorption Spectroscopy (AAS. Thermodynamic properties were measured using DSC, and pasting properties by RVA. Flow curves of 5% pastes were plotted and described using the Herschel-Bulkley model. The structure recovery ratio was measured. AAS analysis established the presence of iron(II and copper(II ions in the samples of modified starches and that potassium and magnesium ions had leached from them. In comparison to unfortified samples, enriching native starch with copper(II ions decreases value of all temperatures of phase transformation about 1.3-2.7 °C, but in case of monostarch phosphates bigger changes (2.8-3.7 °C were observed. Fortified native spelt starch with copper(II ions caused increasing the final viscosity of paste from 362 to 429 mPa·s. However, presence iron(II ions in samples caused reduced its final viscosity by 170 (spelt starch and 103 mPa·s (monostarch phosphate. Furthermore, enriching monostarch phosphate contributed to reduce degree of structure recovery of pastes from 70.9% to 66.6% in case of copper(II ions and to 59.9% in case of iron(II ions.

  12. Developing Cost-Effective Field Assessments of Carbon Stocks in Human-Modified Tropical Forests

    Science.gov (United States)

    Berenguer, Erika; Gardner, Toby A.; Ferreira, Joice; Aragão, Luiz E. O. C.; Camargo, Plínio B.; Cerri, Carlos E.; Durigan, Mariana; Oliveira Junior, Raimundo C.; Vieira, Ima C. G.; Barlow, Jos

    2015-01-01

    Across the tropics, there is a growing financial investment in activities that aim to reduce emissions from deforestation and forest degradation, such as REDD+. However, most tropical countries lack on-the-ground capacity to conduct reliable and replicable assessments of forest carbon stocks, undermining their ability to secure long-term carbon finance for forest conservation programs. Clear guidance on how to reduce the monetary and time costs of field assessments of forest carbon can help tropical countries to overcome this capacity gap. Here we provide such guidance for cost-effective one-off field assessments of forest carbon stocks. We sampled a total of eight components from four different carbon pools (i.e. aboveground, dead wood, litter and soil) in 224 study plots distributed across two regions of eastern Amazon. For each component we estimated survey costs, contribution to total forest carbon stocks and sensitivity to disturbance. Sampling costs varied thirty-one-fold between the most expensive component, soil, and the least, leaf litter. Large live stems (≥10 cm DBH), which represented only 15% of the overall sampling costs, was by far the most important component to be assessed, as it stores the largest amount of carbon and is highly sensitive to disturbance. If large stems are not taxonomically identified, costs can be reduced by a further 51%, while incurring an error in aboveground carbon estimates of only 5% in primary forests, but 31% in secondary forests. For rapid assessments, necessary to help prioritize locations for carbon- conservation activities, sampling of stems ≥20cm DBH without taxonomic identification can predict with confidence (R2 = 0.85) whether an area is relatively carbon-rich or carbon-poor—an approach that is 74% cheaper than sampling and identifying all the stems ≥10cm DBH. We use these results to evaluate the reliability of forest carbon stock estimates provided by the IPCC and FAO when applied to human-modified forests

  13. Developing Cost-Effective Field Assessments of Carbon Stocks in Human-Modified Tropical Forests.

    Science.gov (United States)

    Berenguer, Erika; Gardner, Toby A; Ferreira, Joice; Aragão, Luiz E O C; Camargo, Plínio B; Cerri, Carlos E; Durigan, Mariana; Oliveira Junior, Raimundo C; Vieira, Ima C G; Barlow, Jos

    2015-01-01

    Across the tropics, there is a growing financial investment in activities that aim to reduce emissions from deforestation and forest degradation, such as REDD+. However, most tropical countries lack on-the-ground capacity to conduct reliable and replicable assessments of forest carbon stocks, undermining their ability to secure long-term carbon finance for forest conservation programs. Clear guidance on how to reduce the monetary and time costs of field assessments of forest carbon can help tropical countries to overcome this capacity gap. Here we provide such guidance for cost-effective one-off field assessments of forest carbon stocks. We sampled a total of eight components from four different carbon pools (i.e. aboveground, dead wood, litter and soil) in 224 study plots distributed across two regions of eastern Amazon. For each component we estimated survey costs, contribution to total forest carbon stocks and sensitivity to disturbance. Sampling costs varied thirty-one-fold between the most expensive component, soil, and the least, leaf litter. Large live stems (≥10 cm DBH), which represented only 15% of the overall sampling costs, was by far the most important component to be assessed, as it stores the largest amount of carbon and is highly sensitive to disturbance. If large stems are not taxonomically identified, costs can be reduced by a further 51%, while incurring an error in aboveground carbon estimates of only 5% in primary forests, but 31% in secondary forests. For rapid assessments, necessary to help prioritize locations for carbon- conservation activities, sampling of stems ≥20cm DBH without taxonomic identification can predict with confidence (R2 = 0.85) whether an area is relatively carbon-rich or carbon-poor-an approach that is 74% cheaper than sampling and identifying all the stems ≥10cm DBH. We use these results to evaluate the reliability of forest carbon stock estimates provided by the IPCC and FAO when applied to human-modified forests

  14. Developing Cost-Effective Field Assessments of Carbon Stocks in Human-Modified Tropical Forests.

    Directory of Open Access Journals (Sweden)

    Erika Berenguer

    Full Text Available Across the tropics, there is a growing financial investment in activities that aim to reduce emissions from deforestation and forest degradation, such as REDD+. However, most tropical countries lack on-the-ground capacity to conduct reliable and replicable assessments of forest carbon stocks, undermining their ability to secure long-term carbon finance for forest conservation programs. Clear guidance on how to reduce the monetary and time costs of field assessments of forest carbon can help tropical countries to overcome this capacity gap. Here we provide such guidance for cost-effective one-off field assessments of forest carbon stocks. We sampled a total of eight components from four different carbon pools (i.e. aboveground, dead wood, litter and soil in 224 study plots distributed across two regions of eastern Amazon. For each component we estimated survey costs, contribution to total forest carbon stocks and sensitivity to disturbance. Sampling costs varied thirty-one-fold between the most expensive component, soil, and the least, leaf litter. Large live stems (≥10 cm DBH, which represented only 15% of the overall sampling costs, was by far the most important component to be assessed, as it stores the largest amount of carbon and is highly sensitive to disturbance. If large stems are not taxonomically identified, costs can be reduced by a further 51%, while incurring an error in aboveground carbon estimates of only 5% in primary forests, but 31% in secondary forests. For rapid assessments, necessary to help prioritize locations for carbon- conservation activities, sampling of stems ≥20cm DBH without taxonomic identification can predict with confidence (R2 = 0.85 whether an area is relatively carbon-rich or carbon-poor-an approach that is 74% cheaper than sampling and identifying all the stems ≥10cm DBH. We use these results to evaluate the reliability of forest carbon stock estimates provided by the IPCC and FAO when applied to human

  15. Unconventional gas development and its effect on forested ecosystems in the Northern Appalachians, USA

    Science.gov (United States)

    Drohan, Patrick; Brittingham, Margaret; Mortensen, David; Barlow, Kathryn; Langlois, Lillie

    2017-04-01

    Worldwide unconventional shale-gas development has the potential to cause substantial landscape disturbance. The northeastern U.S.A. Appalachian Mountains across the states of Pennsylvania, West Virginia, Ohio, and Kentucky, are experiencing rapid landscape change as unconventional gas development occurs. We highlight several years of our research from this region in order to demonstrate the unique effect unconventional development has had on forested ecosystems. Infrastructure development has had a wide-reaching and varied effect on forested ecosystems and their services, which has resulted in temporary disturbances and long-lasting ones altering habitats and their viability. Corridor disturbances, such as pipelines, are the most spatially extensive disturbance and have substantially fragmented forest cover. Core forest disturbance, especially, in upper watershed positions, has resulted in disproportionate disturbances to forested ecosystems and their wildlife, and suggests a need for adaptive land management strategies to minimize and mitigate the effects of gas development. Soil and water resources are most affected by surface disturbances; however, soil protection and restoration strategies are evolving as the gas play changes economically. Dynamic soil properties related to soil organic matter and water availability respond uniquely to unconventional gas development and new, flexible restoration strategies are required to support long-term ecosystem stability. While the focus of management and research to date has been on acute disturbances to forested ecosystems, unconventional gas development is clearly a greater chronic, long-term disturbance factor in the Appalachian Mountains. Effectively managing ecosystems where unconventional gas development is occurring is a complicated interplay between public, private and corporate interests.

  16. Memory effects and peak effect in type II superconductors

    International Nuclear Information System (INIS)

    Pasquini, G.; Luna, D.; Eismann, B.; Bettachini, V.; Bekeris, V.

    2007-01-01

    A large amount of experimental and theoretical work has been devoted to understand memory effects (ME) in the solid vortex lattice (VL) but has remained, however, controversial until now. In the vicinity of the anomaly known as the peak effect (PE) both the VL mobility and the measured critical current density are found to be dependent of the dynamical history of the sample, in both low T c (LTS) and high T c (HTS) superconductors. Experiments in YBa 2 Cu 3 O 7 (YBCO) crystals have shown that the mobility of the VL increases after assisting the system with a symmetric AC field (or current) of moderated amplitude. On the other hand, after an asymmetric AC field assists vortices, the VL becomes less mobile. These features indicate that ME in these samples cannot be ascribed to an equilibration process, but probably are related to the organization of the lattice after nearest neighbor re-accommodation or induced plastic VL deformation. Recently, we have shown evidence that in YBCO the PE is a dynamic anomaly observed in the non-linear response, and is absent in the Labusch constant derived from the linear Campbell regime. However, this behavior seems not to be extensive to other systems as the traditional LTS NbSe 2 . In this work, the AC response in the PE region of NbSe 2 and YBCO samples are presented and compared. Very salient differences both in the linear and non-linear response as well as in the ME characteristics indicate that a different physics governs the PE phenomena in each case

  17. Effect of Land Use Legacy on Forest Carbon Dynamics in the NE U.S.

    Science.gov (United States)

    Felzer, B. S.

    2016-12-01

    Forest stand age is a prime determinant of the strength of the carbon sink, as younger, growing forests tend to be stronger sinks than more mature forests. The substantial carbon sink in the NE U.S. is due to forests regrowing from previous disturbance. The particular type of disturbance, whether agricultural abandonment, timber harvest, or fire, can have an impact on the Net Ecosystem Productivity (NEP) observed today, especially for more recently disturbed forests. Nutrient levels, particularly nitrogen, are the most important factor determining the rate of regrowth following disturbance. Agriculture results in depletion of nutrients from the soil, so often results in slower regrowth than timber harvest, for example. If fire is also used during harvesting, nutrient depletion may be even more severe. This study will use the 1 km USDA forest stand age data for the NE U.S. for a series of model sensitivity experiments with the TEM-Hydro model. Three simulations will apply a single disturbance to result in the correct stand age, with agricultural abandonment, timber harvest, and fire applied at the year of disturbance, respectively. A 1/8o run will explore how aggregated stand age affects NEP relative to higher resolution stand age. Preliminary results for a single grid in PA show timber harvest has faster regrowth than regrowth from agricultural abandonment, though fertilization quickens regrowth rates. The effect of crops on NEP is a larger sink than timber harvest in the 5 years following disturbance, but a smaller sink in the decades following, with equivalent NEP values after about 50 years. A simple stand age mixture experiment shows that heterogeneous stand age matters most in the first 20 years following disturbance. These methods will be applied to realistic stand ages for the entire NE U.S. to determine the importance of disturbance type on forest regrowth.

  18. Effects of competition and facilitation on species assemblage in two types of tropical cloud forest.

    Directory of Open Access Journals (Sweden)

    Wenxing Long

    Full Text Available Competition and facilitation between tree individuals are two kinds of non-random processes influencing the structure and functioning of forest communities, but how these two plant-plant interactions change along gradient of resources or environments remains very much a matter of debate. We developed a null model to test the size-distance regression, and assessed the effects of competition and facilitation (including interspecific interactions, intraspecific interactions and overall species interactions on each adult tree species assemblage [diameter at breast height (dbh ≥5 cm] across two types of tropical cloud forest with different environmental and resource regimes. The null model test revealed that 17% to 27% tree species had positive dbh-distance correlations while 11% to 19% tree species showed negative dbh-distance correlations within these two forest types, indicating that both competition and facilitation processes existed during the community assembly. The importance of competition for heterospecific species, and the intensity of competition for both heterospecific and overall species increased from high to low resources for all the shared species spanning the two forests. The importance of facilitation for conspecific and overall species, as well as that the intensity of facilitation for both heterospecific and conspecific species increased with increasing low air temperature stress for all the shared species spanning the two forests. Our results show that both competition and facilitation processes simultaneously affect parts of species assemblage in the tropical cloud forests. Moreover, the fact that nearly 50% species assemblage is not detected with our approaches suggest that tree species in these tropical forest systems are assembled with multiple ecological processes, and that there is a need to explore the processes other than the two biotic interactions in further researches.

  19. Effects of Competition and Facilitation on Species Assemblage in Two Types of Tropical Cloud Forest

    Science.gov (United States)

    Long, Wenxing; Zang, Runguo; Ding, Yi; Huang, Yunfeng

    2013-01-01

    Competition and facilitation between tree individuals are two kinds of non-random processes influencing the structure and functioning of forest communities, but how these two plant-plant interactions change along gradient of resources or environments remains very much a matter of debate. We developed a null model to test the size-distance regression, and assessed the effects of competition and facilitation (including interspecific interactions, intraspecific interactions and overall species interactions) on each adult tree species assemblage [diameter at breast height (dbh) ≥5 cm] across two types of tropical cloud forest with different environmental and resource regimes. The null model test revealed that 17% to 27% tree species had positive dbh-distance correlations while 11% to 19% tree species showed negative dbh-distance correlations within these two forest types, indicating that both competition and facilitation processes existed during the community assembly. The importance of competition for heterospecific species, and the intensity of competition for both heterospecific and overall species increased from high to low resources for all the shared species spanning the two forests. The importance of facilitation for conspecific and overall species, as well as that the intensity of facilitation for both heterospecific and conspecific species increased with increasing low air temperature stress for all the shared species spanning the two forests. Our results show that both competition and facilitation processes simultaneously affect parts of species assemblage in the tropical cloud forests. Moreover, the fact that nearly 50% species assemblage is not detected with our approaches suggest that tree species in these tropical forest systems are assembled with multiple ecological processes, and that there is a need to explore the processes other than the two biotic interactions in further researches. PMID:23565209

  20. Stand dynamics of an oak woodland forest and effects of a restoration treatment on forest health

    Science.gov (United States)

    Stacy L. Clark; Callie J. Schweitzer

    2016-01-01

    Woodland restoration has been conducted in many countries, primarily in Mediterranean regions, but has only recently been attempted on publically and privately owned lands in the eastern United States. We reconstructed historical stand dynamics and tested the immediate effects of an oak

  1. Fire effects on soils in Lake States forests: A compilation of published research to facilitate long-term investigations

    Science.gov (United States)

    Jessica Miesel; P. Goebel; R. Corace; David Hix; Randall Kolka; Brian Palik; David. Mladenoff

    2012-01-01

    Fire-adapted forests of the Lake States region are poorly studied relative to those of the western and southeastern United States and our knowledge base of regional short- and long-term fire effects on soils is limited. We compiled and assessed the body of literature addressing fire effects on soils in Lake States forests to facilitate the re-measurement of previous...

  2. Effectiveness monitoring for the aquatic and riparian component of the Northwest Forest Plan: conceptual framework and options.

    Science.gov (United States)

    Gordon H. Reeves; David B. Hohler; David P. Larsen; David E. Busch; Kim Kratz; Keith Reynolds; Karl F. Stein; Thomas Atzet; Polly Hays; Michael. Tehan

    2004-01-01

    An Aquatic and Riparian Effectiveness Monitoring Plan (AREMP) for the Northwest Forest Plan is intended to characterize the ecological condition of watersheds and aquatic ecosystems. So to determine the effectiveness of the Northwest Forest Plan to meet relevant objectives, this report presents the conceptual foundation of options for use in pilot testing and...

  3. Random forests as cumulative effects models: A case study of lakes and rivers in Muskoka, Canada.

    Science.gov (United States)

    Jones, F Chris; Plewes, Rachel; Murison, Lorna; MacDougall, Mark J; Sinclair, Sarah; Davies, Christie; Bailey, John L; Richardson, Murray; Gunn, John

    2017-10-01

    Cumulative effects assessment (CEA) - a type of environmental appraisal - lacks effective methods for modeling cumulative effects, evaluating indicators of ecosystem condition, and exploring the likely outcomes of development scenarios. Random forests are an extension of classification and regression trees, which model response variables by recursive partitioning. Random forests were used to model a series of candidate ecological indicators that described lakes and rivers from a case study watershed (The Muskoka River Watershed, Canada). Suitability of the candidate indicators for use in cumulative effects assessment and watershed monitoring was assessed according to how well they could be predicted from natural habitat features and how sensitive they were to human land-use. The best models explained 75% of the variation in a multivariate descriptor of lake benthic-macroinvertebrate community structure, and 76% of the variation in the conductivity of river water. Similar results were obtained by cross-validation. Several candidate indicators detected a simulated doubling of urban land-use in their catchments, and a few were able to detect a simulated doubling of agricultural land-use. The paper demonstrates that random forests can be used to describe the combined and singular effects of multiple stressors and natural environmental factors, and furthermore, that random forests can be used to evaluate the performance of monitoring indicators. The numerical methods presented are applicable to any ecosystem and indicator type, and therefore represent a step forward for CEA. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  4. Effects of Increased Nitrogen Availability on C and N Cycles in Tropical Forests: A Meta-Analysis

    Science.gov (United States)

    2015-01-01

    Atmospheric N deposition is predicted to increase four times over its current status in tropical forests by 2030. Our ability to understand the effects of N enrichment on C and N cycles is being challenged by the large heterogeneity of the tropical forest biome. The specific response will depend on the forest’s nutrient status; however, few studies of N addition appear to incorporate the nutrient status in tropical forests, possibly due to difficulties in explaining how this status is maintained. We used a meta-analysis to explore the consequences of the N enrichment on C and N cycles in tropical montane and lowland forests. We tracked changes in aboveground and belowground plant C and N and in mineral soil in response to N addition. We found an increasing trend of plant biomass in montane forests, but not in lowland forests, as well as a greater increase in NO emission in montane forest compared with lowland forest. The N2O and NO emission increase in both forest; however, the N2O increase in lowland forest was significantly even at first time N addition. The NO emission increase showed be greater at first term compared with long term N addition. Moreover, the increase in total soil N, ammonium, microbial N, and dissolved N concentration under N enrichment indicates a rich N status of lowland forests. The available evidence of N addition experiments shows that the lowland forest is richer in N than montane forests. Finally, the greater increase in N leaching and N gas emission highlights the importance of study the N deposition effect on the global climate change. PMID:26633681

  5. Natural vegetation cover in the landscape and edge effects: differential responses of insect orders in a fragmented forest.

    Science.gov (United States)

    González, Ezequiel; Salvo, Adriana; Valladares, Graciela

    2017-10-01

    Human activities have led to global simplification of ecosystems, among which Neotropical dry forests are some of the most threatened. Habitat loss as well as edge effects may affect insect communities. Here, we analyzed insects sampled with pan traps in 9 landscapes (at 5 scales, in 100-500 m diameter circles) comprising cultivated fields and Chaco Serrano forests, at overall community and taxonomic order level. In total 7043 specimens and 456 species of hexapods were captured, with abundance and richness being directly related to forest cover at 500 m and higher at edges in comparison with forest interior. Community composition also varied with forest cover and edge/interior location. Different responses were detected among the 8 dominant orders. Collembola, Hemiptera, and Orthoptera richness and/or abundance were positively related to forest cover at the larger scale, while Thysanoptera abundance increased with forest cover only at the edge. Hymenoptera abundance and richness were negatively related to forest cover at 100 m. Coleoptera, Diptera, and Hymenoptera were more diverse and abundant at the forest edge. The generally negative influence of forest loss on insect communities could have functional consequences for both natural and cultivated systems, and highlights the relevance of forest conservation. Higher diversity at the edges could result from the simultaneous presence of forest and matrix species, although "resource mapping" might be involved for orders that were richer and more abundant at edges. Adjacent crops could benefit from forest proximity since natural enemies and pollinators are well represented in the orders showing positive edge effects. © 2016 Institute of Zoology, Chinese Academy of Sciences.

  6. Forest health in a changing world: Effects of globalization and climate change on forest insect and pathogen impacts

    Science.gov (United States)

    T. D. Ramsfield; Barbara Bentz; M. Faccoli; H. Jactel; E. G. Brockerhoff

    2016-01-01

    Forests and trees throughout the world are increasingly affected by factors related to global change. Expanding international trade has facilitated invasions of numerous insects and pathogens into new regions. Many of these invasions have caused substantial forest damage, economic impacts and losses of ecosystem goods and services provided by trees. Climate...

  7. Long-term protection effects of National Reserve to forest vegetation in 4 decades: biodiversity change analysis of major forest types in Changbai Mountain Nature Reserve, China.

    Science.gov (United States)

    Bai, Fan; Sang, WeiGuo; Li, GuangQi; Liu, RuiGang; Chen, LingZhi; Wang, Kun

    2008-10-01

    The Changbai Mountain Nature Reserve (CNR) was established in 1960 to protect the virgin Korean pine mixed hardwood forest, a typical temperate forest of northeast China. We conducted systematic studies of vascular diversity patterns on the north slope of the CNR mountainside forests (800-1700 m a.s.l.) in 1963 and 2006 respectively. The aim of this comparison is to assess the long-term effects of the protection on plant biodiversity of CNR during the interval 43 years. The research was carried out in three types of forests: mixed coniferous and broad-leaved forest (MCBF), mixed coniferous forest (MCF), and sub-alpine coniferous forest (SCF), characterized by different dominant species. The alpha diversity indicted by species richness and the Shannon-Wiener index were found different in the same elevations and forest types during the 43-year interval. The floral composition and the diversity of vascular species were generally similar along altitudinal gradients before and after the 43-year interval, but some substantial changes were evident with the altitude gradient. In the tree layers, the dominant species in 2006 were similar to those of 1963, though diversity declined with altitude. The indices in the three forest types did not differ significantly between 1963 and 2006, and these values even increased in the MCBF and MCF from 1963 to 2006. However, originally dominant species, P. koraiensis for example, tended to decline, while the proportion of broad-leaved trees increased, and the species turnover in the succession layers trended to shift to higher altitudes. The diversity pattern of the under canopy fluctuated along the altitudinal gradient due to micro-environmental variations. Comparison of the alpha diversity in the three forests shows that the diversity of the shrub and herb layer decreased with time. During the process of survey, we also found some rare and medicinal species disappeared. Analysis indicates that the changes of the diversity pattern in

  8. Resonant Effects in Neutral beam Moderation at TJ-II

    International Nuclear Information System (INIS)

    Guasp, J.; Liniers, M.; Fuentes, C.

    1999-01-01

    The structure of fast ion losses in neutral beam moderation at TJ-II is analysed theoretically, in particular the influence of resonant effects and the radial electric field dependence. The direct losses show strong resonant effects when the ratio of the poloidal and toroidal rotation velocities pass near the values -4/3, -2 or 0. These effects are visible as strong maxima on the loss fractions and also as characteristic trajectory behaviours. The delayed losses present resonant effects also, generally at intermediate energies (5 to 20 KeV for 40 keV injection). Near the resonances the population of passing particles in these losses is very high and the loss fraction can equal or even surpass the direct losses. In these delayed losses the particles concentrate along vertical strips on the loss cone diagrams of roughly constant parallel velocity. This parallel velocity increases with the electric field, the loss maxima are reached usually when the pitch and energy of these strips are near the initial injection values. The trapped particle population in these delayed losses is maximal at null electric and decreases with the field intensity for both potential signs. The corresponding final energies are usually low (1 to 5 keV). Except at extreme potentials, where the -4 resonance can appear, no resonant effects are observed for this population. The resonance ordering is similar for all configurations and follows reasonably the predictions of a simple model. The extreme configurations are dominated by the effects of the 0 and -2 resonances, giving very high loss fractions even for null electric field. In contrast the intermediate configurations, near the Reference one, do not present resonant effects and the losses are moderate at low potentials. Only above 2000 v the resonant effects start to appear. (Author) 11 refs

  9. The changing effects of Alaska’s boreal forests on the climate system

    Science.gov (United States)

    Euskirchen, E.S.; McGuire, A. David; Chapin, F.S.; Rupp, T.S.

    2010-01-01

    In the boreal forests of Alaska, recent changes in climate have influenced the exchange of trace gases, water, and energy between these forests and the atmosphere. These changes in the structure and function of boreal forests can then feed back to impact regional and global climates. In this manuscript, we examine the type and magnitude of the climate feedbacks from boreal forests in Alaska. Research generally suggests that the net effect of a warming climate is a positive regional feedback to warming. Currently, the primary positive climate feedbacks are likely related to decreases in surface albedo due to decreases in snow cover. Fewer negative feedbacks have been identified, and they may not be large enough to counterbalance the large positive feedbacks. These positive feedbacks are most pronounced at the regional scale and reduce the resilience of the boreal vegetation – climate system by amplifying the rate of regional warming. Given the recent warming in this region, the large variety of associated mechanisms that can alter terrestrial ecosystems and influence the climate system, and a reduction in the boreal forest resilience, there is a strong need to continue to quantify and evaluate the feedback pathways.

  10. Effects of gamma radiation on biomass production of ground vegetation under broadleaved forests of northern Wisconsin

    International Nuclear Information System (INIS)

    Zavitkovski, J.; Salmonson, B.J.

    1975-01-01

    Effects of γ irradiation (10,000 Ci 137 Cs source) for one growing season on biomass production of ground vegetation under northern Wisconsin aspen and maple-aspen-birch forests and on an abandoned logging road were evaluated during and one year after irradiation. No significant changes in production were determined during the irradiation year. One year later three distinct zones - semi-devastated, herbaceous, and original forest - developed along the radiation gradient. Biomass production under forest canopies decreased significantly in the semi-devastated zone, increased significantly in the herbaceous zone (primarily responding to additional light), and remained unchanged under the original forest. Logging road vegetation responded similarly but the changes were restricted within higher radiation doses. At comparable levels of radiation, production of species of the logging road vegetation was affected less than that of species under forest canopies. Such a trend was predictable from the generally smaller interphase chromosome volumes, ICV's, of the species on the logging road and from their ability to survive in severe habitats. (author)

  11. Effects of gamma radiation on biomass production of ground vegetation under broadleaved forests of northern Wisconsin

    International Nuclear Information System (INIS)

    Zavitkovski, J.; Salmonson, B.J.

    1977-01-01

    Effects of gamma irradiation (10,000-Ci 137 Cs source) for one growing season on biomass production of ground vegetation under northern Wisconsin aspen and maple-aspen-birch forests and on an abandoned logging road were evaluated during and 1 year after irradiation. No significant changes in production were determined during the irradiation year. One year later three distinct zones--semidevastated, herbaceous, and original forest--developed along the radiation gradient. Biomass production under forest canopies decreased significantly in the semidevastated zone, increased significantly in the herbaceous zone (primarily responding to additional light), and remained unchanged under the original forest. Logging-road vegetation responded similarly, but the changes were restricted within higher radiation doses. At comparable levels of radiation, production of species of the logging-road vegetation was affected less than that of species under forest canopies. Such a trend was predictable from the generally smaller interphase chromosome volumes of the species on the logging road and from their ability to survive in severe habitats

  12. Effect of the degree of anthropization in the structure, at three sites fragmented evergreen piedmont forest

    Directory of Open Access Journals (Sweden)

    Hugo Gabriel Sánchez Villacis

    2017-08-01

    Full Text Available The Ecuadorian Amazon is recognized worldwide for its extraordinary megadiversity and multiplicity of forest goods and services. However, the inadequate practices of extractive use of non-timber forest products, the clearing of extensive areas of forests for the development of oil activity and the unsustainable use of timber as economic sustenance of communities have led to structural and functional changes In ecosystems. The study was carried out in three sites of a degraded evergreen forest of the eastern Amazon (Mera, Shell and Puyo in order to evaluate the effect of the degree of intervention on the forest structure. A floristic inventory was carried out with 60 plots of 25 x 25 m2 and tree species ≥ 2.5 cm d1.30 and species in natural regeneration phase with h <2 m were measured. We found 35 families, 65 genera, 101 species and 2 298 individuals, with Arecaceae, Fabaceae and Moraceae being the most representative botanical families. The degree of anthropization was highly modified where Mera was the best state of conservation. It was evidenced a low floristic diversity with patterns of alteration in the vertical and horizontal structure, distinguished phytosociologically by two strata in the sites of Shell and Puyo and by three in Mera, indicator of structural changes.

  13. Climatic Changes Effects On Spectral Vegetation Indices For Forested Areas Analysis From Satellite Data

    International Nuclear Information System (INIS)

    Zoran, M.; Stefan, S.

    2007-01-01

    Climate-induced changes at the land surface may in turn feed back on the climate itself through changes in soil moisture, vegetation, radiative characteristics, and surface-atmosphere exchanges of water vapor. Thresholding based on biophysical variables derived from time trajectories of satellite data is a new approach to classifying forest land cover via remote . sensing .The input data are composite values of the Normalized Difference Vegetation Index (NDVI). Classification accuracies are function of the class, comparison method and season of the year. The aim of the paper is forest biomass assessment and land-cover changes analysis due to climatic effects

  14. Optimal management of a forested catchment providing timber and carbon sequestration benefits: Climate change effects

    Energy Technology Data Exchange (ETDEWEB)

    Spring, D.A.; MacNally, R. [Monash University, Clayton, Victoria (Australia). Australian Centre for Biodiversity: Analysis, Policy and Management; Kennedy, J.O.S. [La Trobe University, Melbourne (Australia). Department of Economics and Finance

    2005-10-01

    Climate change is predicted to increase fire frequency and exacerbate water scarcity. The effect of these changes on the tree harvest decision in a forested catchment is investigated using stochastic dynamic programming, taking a stand of mountain ash (Eucalyptus regnans) in south-eastern Australia as a case study. We find that for a range of water and carbon sequestration values, it is optimal to cease harvesting in the absence of climate change. Whether it is optimal to do so under climate change will depend on the magnitude of the increases in fire frequency and water value. Potential increases in forest productivity also have a significant impact on the tree harvest decision. (author)

  15. Effect of logging on rodent scatter-hoarding dynamics in tropical forests: implications for plant recruitment.

    Science.gov (United States)

    Gutiérrez-Granados, Gabriel

    2011-06-01

    The present study tested the hypothesis that logging affects the scatter-hoarding behavior of rodents, which, in turn, negatively affects the quantity and quality of Pouteria campechiana (Sapotaceae) seed dispersal. A series of seed stations was established in logged and unlogged forests of ejido Señor, Yucatan Peninsula, and comparisons were made between logged and unlogged forests in terms of: (i) seed removal; (ii) number of seeds hoarded; (iii) hoarding distance; and (iv) the number of recruits and the survival of hoarded seeds. The number of both hoarded and removed seeds was significantly higher in unlogged sites. Furthermore, the mean distance of hoarding was greater in unlogged compared with logged sites. Although recruitment and survival were present in both logged and unlogged sites, there were more surviving seedlings in unlogged sites. The data indicate that both the quantity and quality of seed dispersal are negatively affected by logging because of a change in the rodent scatter-hoarding dynamics. These changes suggest that plant-animal interactions are crucial to the understanding of the ecology and conservation of managed tropical forests. © 2011 ISZS, Blackwell Publishing and IOZ/CAS.

  16. Braking effect of climate and topography on global change-induced upslope forest expansion.

    Science.gov (United States)

    Alatalo, Juha M; Ferrarini, Alessandro

    2017-03-01

    Forests are expected to expand into alpine areas due to global climate change. It has recently been shown that temperature alone cannot realistically explain this process and that upslope tree advance in a warmer scenario may depend on the availability of sites with adequate geomorphic/topographic characteristics. Here, we show that, besides topography (slope and aspect), climate itself can produce a braking effect on the upslope advance of subalpine forests and that tree limit is influenced by non-linear and non-monotonic contributions of the climate variables which act upon treeline upslope advance with varying relative strengths. Our results suggest that global climate change impact on the upslope advance of subalpine forests should be interpreted in a more complex way where climate can both speed up and slow down the process depending on complex patterns of contribution from each climate and non-climate variable.

  17. Tree growth variation in the tropical forest: understanding effects of temperature, rainfall and CO2

    NARCIS (Netherlands)

    Schippers, P.; Sterck, F.J.; Vlam, M.; Zuidema, P.A.

    2015-01-01

    Tropical forest responses to climatic variability have important consequences for global carbon cycling, but are poorly understood. As empirical, correlative studies cannot disentangle the interactive effects of climatic variables on tree growth, we used a tree growth model (IBTREE) to unravel the

  18. Effects of liming on forage availability and nutrient content in a forest impacted by acid rain.

    Directory of Open Access Journals (Sweden)

    Sarah E Pabian

    Full Text Available Acidic deposition and subsequent forest soil acidification and nutrient depletion can affect negatively the growth, health and nutrient content of vegetation, potentially limiting the availability and nutrient content of forage for white-tailed deer (Odocoileus virginianus and other forest herbivores. Liming is a mitigation technique that can be used to restore forest health in acidified areas, but little is known about how it affects the growth or nutrient content of deer forage. We examined the effects of dolomitic limestone application on the growth and chemical composition of understory plants in an acidified forest in central Pennsylvania, with a focus on vegetative groups included as white-tailed deer forage. We used a Before-After-Control-Impact study design with observations 1 year before liming and up to 5 years post-liming on 2 treated and 2 untreated 100-ha sites. Before liming, forage availability and several nutrients were below levels considered optimal for white-tailed deer, and many vegetative characteristics were related to soil chemistry. We observed a positive effect of liming on forb biomass, with a 2.7 fold increase on limed sites, but no biomass response in other vegetation groups. We observed positive effects of liming on calcium and magnesium content and negative effects on aluminum and manganese content of several plant groups. Responses to liming by forbs and plant nutrients show promise for improving vegetation health and forage quality and quantity for deer.

  19. Tree and forest effects on air quality and human health in the United States

    Science.gov (United States)

    David J. Nowak; Satoshi Hirabayashi; Allison Bodine; Eric. Greenfield

    2014-01-01

    Trees remove air pollution by the interception of particulate matter on plant surfaces and the absorption of gaseous pollutants through the leaf stomata. However, the magnitude and value of the effects of trees and forests on air quality and human health across the United States remains unknown. Computer simulations with local environmental data reveal that trees and...

  20. Comparison of silvicultural and natural disturbance effects on terrestrial salamanders in northern hardwood forests

    Science.gov (United States)

    Daniel J. Hocking; Kimberly J. Babbitt; Mariko. Yamasaki

    2013-01-01

    In forested ecosystems timber harvesting has the potential to emulate natural disturbances, thereby maintaining the natural communities adapted to particular disturbances. We compared the effects of even-aged (clearcut and patch cut) and uneven-aged (group cut, single-tree selection) timber management techniques with natural ice-storm damage and unmanipulated reference...

  1. Effects of nitrogen additions on above- and belowground carbon dynamics in two tropical forests

    Science.gov (United States)

    Daniela F. Cusack; Whendee L. Silver; Margaret S. Torn; William H. McDowell

    2011-01-01

    Anthropogenic nitrogen (N) deposition is increasing rapidly in tropical regions, adding N to ecosystems that often have high background N availability. Tropical forests play an important role in the global carbon (C) cycle, yet the effects of N deposition on C cycling in these ecosystems are poorly understood. We used a field N-fertilization experiment in lower and...

  2. Dwarf mistletoe effects on fuel loadings in ponderosa pine forests in northern Arizona

    Science.gov (United States)

    Chad Hoffman; Robert Mathiasen; Carolyn Hull Sieg

    2007-01-01

    Southwestern dwarf mistletoe (Arceuthobium vaginatum (Willd.) J. Presl ssp. cryptopodum) infests about 0.9 million ha in the southwestern United States. Several studies suggest that dwarf mistletoes affect forest fuels and fire behavior; however, few studies have quantified these effects. We compared surface fuel loadings and...

  3. Effects of ungulate herbivory on aspen, cottonwood, and willow development under forest fuels treatment regimes

    Science.gov (United States)

    Bryan A. Endress; Michael J. Wisdom; Martin Vavra; Catherine G. Parks; Brian L. Dick; Bridgett J. Naylor; Jennifer M. Boyd

    2012-01-01

    Herbivory by domestic and wild ungulates can dramatically affect vegetation structure, composition and dynamics in nearly every terrestrial ecosystem of the world. These effects are of particular concern in forests of western North America, where intensive herbivory by native and domestic ungulates has the potential to substantially reduce or eliminate deciduous,...

  4. Satellite detection of land-use change and effects on regional forest aboveground biomass estimates

    Science.gov (United States)

    Daolan Zheng; Linda S. Heath; Mark J. Ducey

    2008-01-01

    We used remote-sensing-driven models to detect land-cover change effects on forest aboveground biomass (AGB) density (Mg·ha−1, dry weight) and total AGB (Tg) in Minnesota, Wisconsin, and Michigan USA, between the years 1992-2001, and conducted an evaluation of the approach. Inputs included remotely-sensed 1992 reflectance data...

  5. The Effects of Litter on Littering Behavior in a Forest Environment

    Science.gov (United States)

    Crump, S. Larry; And Others

    1977-01-01

    The effects of littered and nonlittered areas on littering behavior were determined in picnic areas in the Uinta National Forest, Utah. Littered and nonlittered conditions were controlled by spreading or removing litter from specified areas. Observations revealed that in the nonlittered areas there was more litter than in the littered areas. (CS)

  6. Thinning and riparian buffer configuration effects on down wood abundance in headwater streams in coniferous forests

    Science.gov (United States)

    Adrian Ares; Deanna H. Olson; Klaus J. Puettmann

    2013-01-01

    Down wood is associated with the function, structure, and diversity of riparian systems. Considerable knowledge has been generated regarding down wood stocks and dynamics in temperate forests, but there are few studies on effects of silvicultural practices and riparian buffer design on down wood, particularly in headwater streams. We analyzed interactive eff ects of...

  7. Interactive effects of disturbance and nitrogen availability on phosphorus dynamics of southern Appalachian forests

    Science.gov (United States)

    Corinne E. Block; Jennifer D. Knoepp; Jennifer M. Fraterrigo

    2013-01-01

    Understanding the main and interactive effects of chronically altered resource availability and disturbance on phosphorus (P) availability is increasingly important in light of the rapid pace at which human activities are altering these processes and potentially introducing P limitation. We measured P pools and fluxes in eighteen mixed forest stands at three elevations...

  8. Effects of harvest on carbon and nitrogen dynamics in a Pacific Northwest forest catchment

    Science.gov (United States)

    Alex Abdelnour; Robert B. McKane; Marc Stieglitz; Feifei Pan; Yiwei. Cheng

    2013-01-01

    We used a new ecohydrological model, Visualizing Ecosystems for Land Management Assessments (VELMA), to analyze the effects of forest harvest on catchment carbon and nitrogen dynamics. We applied the model to a 10 ha headwater catchment in the western Oregon Cascade Range where two major disturbance events have occurred during the past 500 years: a stand-replacing fire...

  9. Effects of Liming on Forage Availability and Nutrient Content in a Forest Impacted by Acid Rain

    Science.gov (United States)

    Pabian, Sarah E.; Ermer, Nathan M.; Tzilkowski, Walter M.; Brittingham, Margaret C.

    2012-01-01

    Acidic deposition and subsequent forest soil acidification and nutrient depletion can affect negatively the growth, health and nutrient content of vegetation, potentially limiting the availability and nutrient content of forage for white-tailed deer (Odocoileus virginianus) and other forest herbivores. Liming is a mitigation technique that can be used to restore forest health in acidified areas, but little is known about how it affects the growth or nutrient content of deer forage. We examined the effects of dolomitic limestone application on the growth and chemical composition of understory plants in an acidified forest in central Pennsylvania, with a focus on vegetative groups included as white-tailed deer forage. We used a Before-After-Control-Impact study design with observations 1 year before liming and up to 5 years post-liming on 2 treated and 2 untreated 100-ha sites. Before liming, forage availability and several nutrients were below levels considered optimal for white-tailed deer, and many vegetative characteristics were related to soil chemistry. We observed a positive effect of liming on forb biomass, with a 2.7 fold increase on limed sites, but no biomass response in other vegetation groups. We observed positive effects of liming on calcium and magnesium content and negative effects on aluminum and manganese content of several plant groups. Responses to liming by forbs and plant nutrients show promise for improving vegetation health and forage quality and quantity for deer. PMID:22761890

  10. Effects of restoration techniques on breeding birds in a thermally-impacted bottomland hardwood forest

    Science.gov (United States)

    J. Matthew Buffington; John C. Kilgo; Robert A. Sargent; Karl V. Miller; Brian R. Chapman

    2000-01-01

    We evaluated the effects of revegetation techniques on breeding bird communities in a bottomland hardwood forest impacted by thermal effluent. In 1993, sections of the Pen Branch bottomland on the Savannah River Site, South Carolina, were herbicide-treated (glyphosate), burned, and planted; other sections were planted only while others were unaltered and served as...

  11. Effects of a simulated hurricane disturbance on forest floor microbial communities

    Science.gov (United States)

    Sharon A. Cantrell; Marirosa Molina; D. Jean Lodge; Francisco J. Rivera-Figueroa; Maria Ortiz; Albany A. Marchetti; Mike J. Cyterski; José R. Pérez-Jiménez

    2014-01-01

    Forest floor microbial communities play a critical role in the processes of decomposition and nutrient cycling. The impact of cultivation, contamination, fire, and land management on soil microbial communities have been studied but there are few studies of microbial responses to the effects of tropical storms. The Canopy Trimming Experiment was executed in the Luquillo...

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

    Science.gov (United States)

    Stephen D. Sebestyen; Elon S. Verry

    2011-01-01

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

  13. THE EFFECT OF PVC-BASED MEMBRANE COMPOSITION AND Zn(II, Cd(II AND Pb(II INTERFERING IONS TO Hg(II ION SELECTIVE ELECTRODE (ISE PERFORMANCE BY USING DBA218C6 IONOPHORE

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    Abd. Wahid Wahab

    2010-06-01

    Full Text Available The effect of PVC (Polyvinylchloride-Based Membrane Composition to Ion Selective Electrode (ISE-Hg(II Performance using Ionophore DBA218C6 (N,N'-Dibenzyl-1,4,10,13-tetraoxa-7,16-diazacyclo octadecane,  Plasticizer NPOE (Nitrophenyl Octhyl Ether, Anionic Site KTCPB (Potassium Tetrakis (4-chloro phenyl borate have been performed. Membrane compositions used were:(a PVC (30 mg, NPOE (60 mg, DBA218C6(6 mg and KTCPB (4 mg; (b PVC(30 mg, NPOE (60 mg, DBA218C6(7 mg and KTCPB (3 mg; (c PVC (30 mg, NPOE (59 mg, DBA218C6 (8 mg and KTCPB( 3 mg. The concentration range of interference ions Zn(II, Cd(II and Pb(II  were 1.0 x 10-3 - 1.0 x 10-1 M. ISE-Hg(II performance for membrane composition of 30 : 60 : 6 : 4 was 26.34 mV per decade (Nernstian Slope value on Hg(II concentration range of 1.0x10-6 - 1.0 x 10-1 M , membrane composition of 30 : 60 : 7 : 3 was 27.71 mV per decade on Hg(II concentration range of 1.0 x10-6 - 1.0 x10-1 M, and membrane composition of 30 : 59 : 8 : 3 was 28.52 mV per decade on Hg(II concentration range of  1.0 x10-6 - 1.0 x10-1 M with activity between pH 1.0-3.0. The concentration of interference ions : Zn(II, Cd(II and Pb(II in the range of 1.0 x 10-3 - 1.0 x 10-1 M with the ratio of the primary ion to interference ions of 4 : 1 gave real effect. As results, selectivities and sensitivities between ISE-Hg(II and Ionophore DBA218C6 could be determined by PVC-Based Membrane Composition and the effect of Zn(II, Cd(II and Pb(II  interference ions was observed in the concentration of 1,0 x10-3 - 1,0 x10-1 M.   Keywords: membrane composition effect, ionophore DBA218C6, ISE-Hg(II

  14. Effects of nitrogen and phosphorus additions on soil microbial biomass and community structure in two reforested tropical forests

    Science.gov (United States)

    Liu, Lei; Gundersen, Per; Zhang, Wei; Zhang, Tao; Chen, Hao; Mo, Jiangming

    2015-09-01

    Elevated nitrogen (N) deposition may aggravate phosphorus (P) deficiency in forests in the warm humid regions of China. To our knowledge, the interactive effects of long-term N deposition and P availability on soil microorganisms in tropical replanted forests remain unclear. We conducted an N and P manipulation experiment with four treatments: control, N addition (15 g N m-2·yr-1), P addition (15 g P m-2·yr-1), and N and P addition (15 + 15 g N and P m-2·yr-1, respectively) in disturbed (planted pine forest with recent harvests of understory vegetation and litter) and rehabilitated (planted with pine, but mixed with broadleaf returning by natural succession) forests in southern China. Nitrogen addition did not significantly affect soil microbial biomass, but significantly decreased the abundance of gram-negative bacteria PLFAs in both forest types. Microbial biomass increased significantly after P addition in the disturbed forest but not in the rehabilitated forest. No interactions between N and P additions on soil microorganisms were observed in either forest type. Our results suggest that microbial growth in replanted forests of southern China may be limited by P rather than by N, and this P limitation may be greater in disturbed forests.

  15. Comparing Effects of Climate Warming, Fire, and Timber Harvesting on a Boreal Forest Landscape in Northeastern China

    Science.gov (United States)

    Li, Xiaona; He, Hong S.; Wu, Zhiwei; Liang, Yu; Schneiderman, Jeffrey E.

    2013-01-01

    Forest management under a changing climate requires assessing the effects of climate warming and disturbance on the composition, age structure, and spatial patterns of tree species. We investigated these effects on a boreal forest in northeastern China using a factorial experimental design and simulation modeling. We used a spatially explicit forest landscape model (LANDIS) to evaluate the effects of three independent variables: climate (current and expected future), fire regime (current and increased fire), and timber harvesting (no harvest and legal harvest). Simulations indicate that this forested landscape would be significantly impacted under a changing climate. Climate warming would significantly increase the abundance of most trees, especially broadleaf species (aspen, poplar, and willow). However, climate warming would have less impact on the abundance of conifers, diversity of forest age structure, and variation in spatial landscape structure than burning and harvesting. Burning was the predominant influence in the abundance of conifers except larch and the abundance of trees in mid-stage. Harvesting impacts were greatest for the abundance of larch and birch, and the abundance of trees during establishment stage (1–40 years), early stage (41–80 years) and old- growth stage (>180 years). Disturbance by timber harvesting and burning may significantly alter forest ecosystem dynamics by increasing forest fragmentation and decreasing forest diversity. Results from the simulations provide insight into the long term management of this boreal forest. PMID:23573209

  16. Effects of Natural and Human-Assisted Regeneration on Landscape Dynamics in a Korean Pine Forest in Northeast China

    Science.gov (United States)

    Zhao, Fuqiang; Yang, Jian; He, Hong S.; Dai, Limin

    2013-01-01

    Improper forest harvesting can potentially degrade forest ecosystem functions and services. Human-assisted regeneration (e.g., planting) is often used to increase the rate of forest recovery and thereby reduce regeneration failure. Seed dispersal is a fundamental ecological process that can also influence spatio-temporal patterns of forest regeneration. In this study, we investigated the relative contribution of planting and seed dispersal on forest regeneration at landscape scales. Because such influences can be further complicated by timber harvest intensity and seed availability within and around harvested area, we also evaluated the effects of those factors on forest landscape dynamics. We used the forest landscape model LANDIS to simulate the dynamics of Korean pine-broadleaf mixed forests in Northeast China. We considered three factors: timber harvest intensity (3 levels), seed dispersal and whether or not planting was used. The results showed that planting was more important in maintaining the abundance of Korean pine (Pinus koraiensis), a climax keystone species in this region, under the high-intensity harvesting option during early succession. In contrast, seed dispersal was more important during late succession. Korean pine can be successfully regenerated through seed dispersal under low and medium harvest intensities. Our results also indicated that effective natural regeneration will require protecting seed-production trees (seed rain). This study results provide a basis for more effectively managing Chinese temperate forests and possibly other similar ecosystems. PMID:24324785

  17. Interactive effects of land use history and natural disturbance on seedling dynamics in a subtropical forest.

    Science.gov (United States)

    Comita, Liza S; Thompson, Jill; Uriarte, Maria; Jonckheere, Inge; Canham, Charles D; Zimmerman, Jess K

    2010-07-01

    , suggesting that hurricanes act to homogenize differences in species composition between areas with differing land use histories by increasing secondary-forest species regeneration in areas that experienced little direct human disturbance. Our results suggest that, through effects on seedling dynamics, hurricanes may extend the signature of land use history beyond the average recovery time of forests not subject to intense natural disturbance events.

  18. Effect of isoprene emissions from major forests on ozone formation in the city of Shanghai, China

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    F. Geng

    2011-10-01

    Full Text Available Ambient surface level concentrations of isoprene (C5H8 were measured in the major forest regions located south of Shanghai, China. Because there is a large coverage of broad-leaved trees in this region, high concentrations of isoprene were measured, ranging from 1 to 6 ppbv. A regional dynamical/chemical model (WRF-Chem is applied for studying the effect of such high concentrations of isoprene on the ozone production in the city of Shanghai. The evaluation of the model shows that the calculated isoprene concentrations agree with the measured concentrations when the measured isoprene concentrations are lower than 3 ppb, but underestimate the measurements when the measured values are higher than 3 ppb. Isoprene was underestimated only at sampling sites near large bamboo plantations, a high isoprene source, indicating the need to include geospatially resolved bamboo distributions in the biogenic emission model. The assessment of the impact of isoprene on ozone formation suggests that the concentrations of peroxy radicals (RO2 are significantly enhanced due to the oxidation of isoprene, with a maximum of 30 ppt. However, the enhancement of RO2 is confined to the forested regions. Because the concentrations of NOx were low in the forest regions, the ozone production due to the oxidation of isoprene (C5H8 + OH → → RO2 + NO → → O3 is low (less than 2–3 ppb h−1. The calculation further suggests that the oxidation of isoprene leads to the enhancement of carbonyls (such as formaldehyde and acetaldehyde in the regions downwind of the forests, due to continuous oxidation of isoprene in the forest air. As a result, the concentrations of HO2 radical are enhanced, resulting from the photo-disassociation of formaldehyde and acetaldehyde. Because the enhancement of HO2 radical occurs in regions downwind of the forests

  19. Nitrogen Fertilization Effects on Long-term Patterns of Litter Decomposition in Two Humid Tropical Forests

    Science.gov (United States)

    Cusack, D. F.; Silver, W. L.; Torn, M. S.; McDowell, W. H.

    2009-12-01

    Nitrogen (N) deposition is known to impact decomposition in temperate ecosystems, but less is known about the effects of added N in tropical forests, where background soil N availability is relatively high. We examined changes in patterns and drivers of long-term litter decomposition with N fertilization in a lower elevation rainforest and an upper elevation cloud forest in the Luquillo Mountains, Puerto Rico. We hypothesized that increased N would accelerate initial decomposition rates, while slowing later stages of decomposition. We predicted that litterfall chemistry would not change with N fertilization in these forests, but rather that N addition to the forest floor would directly alter the activity of microbial decomposers. We measured decomposition rates over three years for mixed native litter and a common substrate. We used 13C-nuclear magnetic resonance (NMR) spectroscopy to assess effects of N addition on initial litter chemical characteristics. Carbon and N concentrations of initial litter and decomposing litter were measured at multiple time points over the three years. As indices of microbial activity, we measured hydrolytic enzymes that degrade simpler C substrates, and oxidative enzymes that degrade more complex compounds, in decomposing litter over the three years. Decomposition rates for the common substrate were significantly higher in fertilized versus control plots in the lower elevation forest (p fertilized plots versus 0.7 ± 0.2 in control plots (per year, mean ± one s.e., n = 3). Initial litterfall C:N ratios and 13C-NMR chemistry did not respond significantly to N fertilization. Litter N concentrations were significant predictors of decomposition rates, and N fertilization did significantly alter C:N ratios of litter over the course of decomposition. Extracellular enzyme activities responded to N additions for some time points. These results indicate that litter turnover in tropical forests is likely to be sensitive to N deposition

  20. Effects of the herbicide glyphosate on non-target plant native species from Chaco forest (Argentina).

    Science.gov (United States)

    Florencia, Ferreira María; Carolina, Torres; Enzo, Bracamonte; Leonardo, Galetto

    2017-10-01

    Agriculture based on transgenic crops has expanded in Argentina into areas formerly occupied by Chaco forest. Even though glyphosate is the herbicide most widely used in the world, increasing evidence indicates severe ecotoxicological effects on non-target organisms as native plants. The aim of this work is to determine glyphosate effects on 23 native species present in the remaining Chaco forests immersed in agricultural matrices. This is a laboratory/greenhouse approach studying acute effects on seedlings after 21 days. A gradient of glyphosate rates (525, 1050, 2100, 4200, and 8400g ai/Ha; recommended field application rate (RFAR) = 2100g ai/Ha) was applied on four-week seedlings cultivated in a greenhouse and response variables (phytotoxicity, growth reduction, and sensitivity to the herbicide) were measured. This gradient of herbicide rates covers realistic rates of glyphosate applications in the crop field and also those that can reach vegetation of forest relicts by off-target drift and overspray. Testing was performed following guidelines for vegetative vigour (post-germination spray). All species showed lethal or sublethal effects after the application of the 25% of RFAR (50% of species showed severe phytotoxicity or death and 70% of species showed growth reduction). The results showed a gradient of sensitivity to glyphosate by which some of the studied species are very sensitive to glyphosate and seedlings died with 25% of RFAR while other species can be classified as herbicide-tolerant. Thus, the vegetation present in the forest relicts could be strongly affected by glyphosate application on crops. Lethal and sublethal effects of glyphosate on non-target plants could promote both the loss of biodiversity in native forest relicts immersed in the agroecosystems and the selection of new crop weeds considering that some biotypes are continuously exposed to low doses of glyphosate. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Effects of Simulated Forest Cover Change on Projected Climate Change – a Case Study of Hungary

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    GÁLOS, Borbála

    2011-01-01

    Full Text Available Climatic effects of forest cover change have been investigated for Hungary applying theregional climate model REMO. For the end of the 21st century (2071–2100 case studies have beenanalyzed assuming maximal afforestation (forests covering all vegetated area and completedeforestation (forests replaced by grasslands of the country. For 2021–2025, the climatic influence ofthe potential afforestation based on a detailed national survey has been assessed. The simulationresults indicate that maximal afforestation may reduce the projected climate change through coolerand moister conditions for the entire summer period. The magnitude of the simulated climate changemitigating effect of the forest cover increase differs among regions. The smallest climatic benefit wascalculated in the southwestern region, in the area with the potentially strongest climate change. Thestrongest effects of maximal afforestation are expected in the northeastern part of the country. Here,half of the projected precipitation decrease could be relieved and the probability of summer droughtscould be reduced. The potential afforestation has a very slight feedback on the regional climatecompared to the maximal afforestation scenario.

  2. Effects of Forest Therapy on Depressive Symptoms among Adults: A Systematic Review

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    Insook Lee

    2017-03-01

    Full Text Available This study systematically reviewed forest therapy programs designed to decrease the level of depression among adults and assessed the methodological rigor and scientific evidence quality of existing research studies to guide future studies. This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The authors independently screened full-text articles from various databases using the following criteria: (1 intervention studies assessing the effects of forest therapy on depressive symptoms in adults aged 18 years and older; (2 studies including at least one control group or condition; (3 peer-reviewed studies; and (4 been published either in English or Korean before July 2016. The Scottish Intercollegiate Guideline Network measurement tool was used to assess the risk of bias in each trial. In the final sample, 28 articles (English: 13, Korean: 15 were included in the systematic review. We concluded that forest therapy is an emerging and effective intervention for decreasing adults’ depression levels. However, the included studies lacked methodological rigor. Future studies assessing the long-term effect of forest therapy on depression using rigorous study designs are needed.

  3. Effect of differential forest management on land-use change (LUC) in a tropical hill forest of Malaysia.

    Science.gov (United States)

    Masum, Kazi Mohammad; Mansor, Asyraf; Sah, Shahrul Anuar Mohd; Lim, Hwee San

    2017-09-15

    Forest ownership is considered as a vital aspect for sustainable management of forest and its associated biodiversity. The Global Forest Resources Assessment 2015 reported that privately owned forest area are increasing on a global scale, but deforestation was found very active in privately owned hill forest areas of Malaysia. Penang State was purposively chosen as it has been experiencing rapid and radical changes due to urban expansion over the last three decades. In this study, analyses of land-use changes were done by PCI Geomatica using Landsat images from 1991 to 2015, future trends of land-use change were assessed using EXCEL forecast function, and its impact on the surrounding environment were conducted by reviewing already published articles on changing environment of the study area. This study revealed an annual deforestation rate of 1.4% in Penang Island since 1991. Trend analysis forecasted a forest area smaller than the current forest reserves by the year 2039. Impact analysis revealed a rapid biodiversity loss with increasing landslides, mudflows, water pollution, flash flood, and health hazard. An immediate ban over hill-land development is crucial for overall environmental safety. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. The effects of forest-savanna-grassland gradients on bird communities of Chiquitano Dry Forests domain, in western Brazil.

    Science.gov (United States)

    Godoi, Mauricio N; Souza, Edivaldo O DE

    2016-01-01

    Different vegetation types are distributed in mountains according to altitude, topography and soil. The composition and structure of bird communities in these areas can change in relation to the vegetation gradient, with particular communities occupying each habitat type. In this study we present the changes in composition, species richness and bird abundance over the gradient of forests, savannas and altitudinal grasslands of Maciço do Urucum, a mountainous region located in the Chiquitano Dry Forests domain in western Brazil. We recorded 165 bird species through qualitative and quantitative methods. Forested savannas, riparian forests and submontane forests presented the highest richness and abundance of birds, while arboreal savannas and altitudinal grasslands had intermediate and low values, respectively. The bird composition was similar between riparian and submontane forests, while other vegetation types present more dissimilar bird communities. Our results show differences in composition, richness and bird abundance among the vegetation types present at Maciço do Urucum, and highlight an important function of vegetation gradients for the conservation of bird communities in mountains. Additionally, this is the first study of the bird communities in the Brazilian Chiquitano Dry Forests, an important domain in the west of Brazil which has been poorly studied.

  5. The effects of forest-savanna-grassland gradients on bird communities of Chiquitano Dry Forests domain, in western Brazil

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    MAURICIO N. GODOI

    Full Text Available ABSTRACT Different vegetation types are distributed in mountains according to altitude, topography and soil. The composition and structure of bird communities in these areas can change in relation to the vegetation gradient, with particular communities occupying each habitat type. In this study we present the changes in composition, species richness and bird abundance over the gradient of forests, savannas and altitudinal grasslands of Maciço do Urucum, a mountainous region located in the Chiquitano Dry Forests domain in western Brazil. We recorded 165 bird species through qualitative and quantitative methods. Forested savannas, riparian forests and submontane forests presented the highest richness and abundance of birds, while arboreal savannas and altitudinal grasslands had intermediate and low values, respectively. The bird composition was similar between riparian and submontane forests, while other vegetation types present more dissimilar bird communities. Our results show differences in composition, richness and bird abundance among the vegetation types present at Maciço do Urucum, and highlight an important function of vegetation gradients for the conservation of bird communities in mountains. Additionally, this is the first study of the bird communities in the Brazilian Chiquitano Dry Forests, an important domain in the west of Brazil which has been poorly studied.

  6. Effects of urotensin II receptor antagonist, GSK1440115, in asthma

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    Alison D Portnoy

    2013-04-01

    Full Text Available Background: Urotensin II (U-II is highly expressed in the human lung and has been implicated in regulating respiratory physiology in preclinical studies. Our objective was to test antagonism of the urotensin receptor (UT by GSK1440115, a novel, competitive and selective inhibitor of the UT receptor, as a therapeutic strategy for the treatment of asthma. Methods: Safety, tolerability and pharmacokinetics (PK of single doses of GSK1440115 (1–750 mg were assessed in a Phase I, placebo-controlled study in 70 healthy subjects. In a Phase Ib study, 12 asthmatic patients were randomized into a 2-period, single-blind crossover study and treated with single doses of 750 mg GSK1440115 or placebo and given a methacholine challenge. Results: Administration of GSK1440115 was safe and well-tolerated in healthy subjects and asthmatic patients. In both studies, there was a high degree of variability in the observed PK following oral dosing with GSK1440115 at all doses. There was a marked food effect in healthy subjects at the 50 mg dose. In the presence of food at the 750 mg dose, the time to maximal concentration was between 2 and 6 hours and the terminal half-life was short at approximately 2 hours. All asthmatic patients maintained greater than the predicted concentration levels necessary to achieve predicted 96% receptor occupancy for >=3 hours (between 4-7 hours post-dose. There were no apparent trends or relationships between the systemic plasma exposure of GSK1440115 and pharmacodynamic endpoints, PC20 after methacholine challenge and FEV1, in asthmatics. Conclusion: While GSK1440115 was safe and well-tolerated, it did not induce bronchodilation in asthmatics, or protect against methacholine-induced bronchospasm, suggesting that acute UT antagonism is not likely to provide benefit as an acute bronchodilator in this patient population.

  7. Physiological and Psychological Effects of Forest Therapy on Middle-Aged Males with High-Normal Blood Pressure

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    Hiroko Ochiai

    2015-02-01

    Full Text Available Time spent walking and relaxing in a forest environment (“forest bathing” or “forest therapy” has well demonstrated anti-stress effects in healthy adults, but benefits for ill or at-risk populations have not been reported. The present study assessed the physiological and psychological effects of forest therapy (relaxation and stress management activity in the forest on middle-aged males with high-normal blood pressure. Blood pressure and several physiological and psychological indices of stress were measured the day before and approximately 2 h following forest therapy. Both pre- and post-treatment measures were conducted at the same time of day to avoid circadian influences. Systolic and diastolic blood pressure (BP, urinary adrenaline, and serum cortisol were all significantly lower than baseline following forest therapy (p < 0.05. Subjects reported feeling significantly more “relaxed” and “natural” according to the Semantic Differential (SD method. Profile of Mood State (POMS negative mood subscale scores for “tension-anxiety,” “confusion,” and “anger-hostility,” as well as the Total Mood Disturbance (TMD score were significantly lower following forest therapy. These results highlight that forest is a promising treatment strategy to reduce blood pressure into the optimal range and possibly prevent progression to clinical hypertension in middle-aged males with high-normal blood pressure.

  8. Effect of National-Scale Afforestation on Forest Water Supply and Soil Loss in South Korea, 1971–2010

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    Gang Sun Kim

    2017-06-01

    Full Text Available Afforestation of forests in South Korea may provide an example of the benefit of afforestation on precipitation storage and erosion control. In this study, we presented the effects of afforestation on water supply and soil loss prevention. A spatio-temporal simulation of forest water yield and soil loss was performed from 1971–2010 using InVEST water yield and SWAT models. A forest stock change map was produced by combining land cover data and National Forest Inventory data. The forest water yield increased about twice with changes in forest stock and climate from 1971–2010 and showed a spatially homogeneous water supply capacity. In the same period, the soil loss decreased more than three times, and the volatility of soil loss, in the 2010s, was smaller than before. The analysis of the change in forest stock without considering climate change showed an increase of 43% in forest water yield and a decrease of 87% in soil loss. An increase in precipitation increased the water yield, but also increased the soil loss volume. A change in forest stock led to positive changes in both. This study presents functional positive effects of the afforestation program in South Korea that can be useful in various afforestation programs in other countries.

  9. The Effects of Forest Therapy on Coping with Chronic Widespread Pain: Physiological and Psychological Differences between Participants in a Forest Therapy Program and a Control Group

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    Jin-Woo Han

    2016-02-01

    Full Text Available This study aimed to investigate the effects of a two-day forest therapy program on individuals with chronic widespread pain. Sixty one employees of a public organization providing building and facilities management services within the Seoul Metropolitan area participated in the study. Participants were assigned to an experimental group (n = 33 who participated in a forest therapy program or a control group (n = 28 on a non-random basis. Pre- and post-measures of heart rate variability (HRV, Natural Killer cell (NK cell activity, self-reported pain using the visual analog scale (VAS, depression level using the Beck Depression Inventory (BDI, and health-related quality of life measures using the EuroQol Visual Analog Scale (EQ-VAS were collected in both groups. The results showed that participants in the forest therapy group, as compared to the control group, showed physiological improvement as indicated by a significant increase in some measures of HRV and an increase in immune competence as indicated by NK cell activity. Participants in the forest therapy group also reported significant decreases in pain and depression, and a significant improvement in health-related quality of life. These results support the hypothesis that forest therapy is an effective intervention to relieve pain and associated psychological and physiological symptoms in individuals with chronic widespread pain.

  10. The effect of riparian forest management on flood risk and flood hydrology

    Science.gov (United States)

    Dixon, S.; Sear, D.

    2012-04-01

    Riparian forests are a source of in-stream Large Wood. In-stream Large Wood has been shown to produce complex in-stream hydraulic patterns which can act to dissipate flood energy and attenuate flood peaks. Furthermore riparian forest are also commonly characterised by a complex flood plain surface which acts to slow overbank flow. Increased channel and floodplain flow resistance in forested catchments has the effect of increasing the duration and height of overbank inundation locally, but also, and significantly, can potentially increase flood wave travel time and reduce flood peak magnitude at downstream locations. River restoration programmes can include riparian afforestation of headwater stream and increases to in-stream hydraulic roughness; there is a need for research to quantify the effect of such changes on flood hydrology. This study uses a loosely coupled modelling approach to investigate the response of flood behaviour to catchment wide forest management strategies. A USDA Riparian Forest growth model (NE-CWD) calibrated for UK forests using Forestry Commission Biometrics data is used to deliver predictions of in-stream wood loads under different forest management scenarios over time. Scenarios include continuation of plantation management with harvesting/thinning, hands-off management with no harvesting and reforestation of cleared areas of the catchment. Wood load predictions from NE-CWD are translated into predictions of logjam frequency and values for channel hydraulic roughness based on field data collected over two field seasons. Flood modelling is conducted using OVERFLOW, a model developed for the simulation of flood events where the magnitude and travel time of a flood peak to a downstream location are of interest. Predictions linking land use to flood behaviour can be delivered by varying the forest management scenarios within NE-CWD and the associated channel and floodplain roughness. The output of OVERFLOW includes individual contributions

  11. Post-Crackdown Effectiveness of Field-Based Forest Law Enforcement in the Brazilian Amazon

    Science.gov (United States)

    Börner, Jan; Kis-Katos, Krisztina; Hargrave, Jorge; König, Konstantin

    2015-01-01

    Regulatory enforcement of forest conservation laws is often dismissed as an ineffective approach to reducing tropical forest loss. Yet, effective enforcement is often a precondition for alternative conservation measures, such as payments for environmental services, to achieve desired outcomes. Fair and efficient policies to reducing emissions from deforestation and forest degradation (REDD) will thus crucially depend on understanding the determinants and requirements of enforcement effectiveness. Among potential REDD candidate countries, Brazil is considered to possess the most advanced deforestation monitoring and enforcement infrastructure. This study explores a unique dataset of over 15 thousand point coordinates of enforcement missions in the Brazilian Amazon during 2009 and 2010, after major reductions of deforestation in the region. We study whether local deforestation patterns have been affected by field-based enforcement and to what extent these effects vary across administrative boundaries. Spatial matching and regression techniques are applied at different spatial resolutions. We find that field-based enforcement operations have not been universally effective in deterring deforestation during our observation period. Inspections have been most effective in reducing large-scale deforestation in the states of Mato Grosso and Pará, where average conservation effects were 4.0 and 9.9 hectares per inspection, respectively. Despite regional and actor-specific heterogeneity in inspection effectiveness, field-based law enforcement is highly cost-effective on average and might be enhanced by closer collaboration between national and state-level authorities. PMID:25875656

  12. Post-crackdown effectiveness of field-based forest law enforcement in the Brazilian Amazon.

    Directory of Open Access Journals (Sweden)

    Jan Börner

    Full Text Available Regulatory enforcement of forest conservation laws is often dismissed as an ineffective approach to reducing tropical forest loss. Yet, effective enforcement is often a precondition for alternative conservation measures, such as payments for environmental services, to achieve desired outcomes. Fair and efficient policies to reducing emissions from deforestation and forest degradation (REDD will thus crucially depend on understanding the determinants and requirements of enforcement effectiveness. Among potential REDD candidate countries, Brazil is considered to possess the most advanced deforestation monitoring and enforcement infrastructure. This study explores a unique dataset of over 15 thousand point coordinates of enforcement missions in the Brazilian Amazon during 2009 and 2010, after major reductions of deforestation in the region. We study whether local deforestation patterns have been affected by field-based enforcement and to what extent these effects vary across administrative boundaries. Spatial matching and regression techniques are applied at different spatial resolutions. We find that field-based enforcement operations have not been universally effective in deterring deforestation during our observation period. Inspections have been most effective in reducing large-scale deforestation in the states of Mato Grosso and Pará, where average conservation effects were 4.0 and 9.9 hectares per inspection, respectively. Despite regional and actor-specific heterogeneity in inspection effectiveness, field-based law enforcement is highly cost-effective on average and might be enhanced by closer collaboration between national and state-level authorities.

  13. Post-crackdown effectiveness of field-based forest law enforcement in the Brazilian Amazon.

    Science.gov (United States)

    Börner, Jan; Kis-Katos, Krisztina; Hargrave, Jorge; König, Konstantin

    2015-01-01

    Regulatory enforcement of forest conservation laws is often dismissed as an ineffective approach to reducing tropical forest loss. Yet, effective enforcement is often a precondition for alternative conservation measures, such as payments for environmental services, to achieve desired outcomes. Fair and efficient policies to reducing emissions from deforestation and forest degradation (REDD) will thus crucially depend on understanding the determinants and requirements of enforcement effectiveness. Among potential REDD candidate countries, Brazil is considered to possess the most advanced deforestation monitoring and enforcement infrastructure. This study explores a unique dataset of over 15 thousand point coordinates of enforcement missions in the Brazilian Amazon during 2009 and 2010, after major reductions of deforestation in the region. We study whether local deforestation patterns have been affected by field-based enforcement and to what extent these effects vary across administrative boundaries. Spatial matching and regression techniques are applied at different spatial resolutions. We find that field-based enforcement operations have not been universally effective in deterring deforestation during our observation period. Inspections have been most effective in reducing large-scale deforestation in the states of Mato Grosso and Pará, where average conservation effects were 4.0 and 9.9 hectares per inspection, respectively. Despite regional and actor-specific heterogeneity in inspection effectiveness, field-based law enforcement is highly cost-effective on average and might be enhanced by closer collaboration between national and state-level authorities.

  14. High-Frequency H-1 NMR Chemical Shifts of Sn-II and Pb-II Hydrides Induced by Relativistic Effects: Quest for Pb-II Hydrides

    Czech Academy of Sciences Publication Activity Database

    Vícha, J.; Marek, R.; Straka, Michal

    2016-01-01

    Roč. 55, č. 20 (2016), s. 10302-10309 ISSN 0020-1669 Institutional support: RVO:61388963 Keywords : hydrides of TlI and PbII * high-frequency 1H chemical shifts * relativistic effects Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 4.857, year: 2016

  15. Urbanization Impacts on Mammals across Urban-Forest Edges and a Predictive Model of Edge Effects

    Science.gov (United States)

    Villaseñor, Nélida R.; Driscoll, Don A.; Escobar, Martín A. H.; Gibbons, Philip; Lindenmayer, David B.

    2014-01-01

    With accelerating rates of urbanization worldwide, a better understanding of ecological processes at the wildland-urban interface is critical to conserve biodiversity. We explored the effects of high and low-density housing developments on forest-dwelling mammals. Based on habitat characteristics, we expected a gradual decline in species abundance across forest-urban edges and an increased decline rate in higher contrast edges. We surveyed arboreal mammals in sites of high and low housing density along 600 m transects that spanned urban areas and areas turn on adjacent native forest. We also surveyed forest controls to test whether edge effects extended beyond our edge transects. We fitted models describing richness, total abundance and individual species abundance. Low-density housing developments provided suitable habitat for most arboreal mammals. In contrast, high-density housing developments had lower species richness, total abundance and individual species abundance, but supported the highest abundances of an urban adapter (Trichosurus vulpecula). We did not find the predicted gradual decline in species abundance. Of four species analysed, three exhibited no response to the proximity of urban boundaries, but spilled over into adjacent urban habitat to differing extents. One species (Petaurus australis) had an extended negative response to urban boundaries, suggesting that urban development has impacts beyond 300 m into adjacent forest. Our empirical work demonstrates that high-density housing developments have negative effects on both community and species level responses, except for one urban adapter. We developed a new predictive model of edge effects based on our results and the literature. To predict animal responses across edges, our framework integrates for first time: (1) habitat quality/preference, (2) species response with the proximity to the adjacent habitat, and (3) spillover extent/sensitivity to adjacent habitat boundaries. This framework will

  16. Urbanization impacts on mammals across urban-forest edges and a predictive model of edge effects.

    Science.gov (United States)

    Villaseñor, Nélida R; Driscoll, Don A; Escobar, Martín A H; Gibbons, Philip; Lindenmayer, David B

    2014-01-01

    With accelerating rates of urbanization worldwide, a better understanding of ecological processes at the wildland-urban interface is critical to conserve biodiversity. We explored the effects of high and low-density housing developments on forest-dwelling mammals. Based on habitat characteristics, we expected a gradual decline in species abundance across forest-urban edges and an increased decline rate in higher contrast edges. We surveyed arboreal mammals in sites of high and low housing density along 600 m transects that spanned urban areas and areas turn on adjacent native forest. We also surveyed forest controls to test whether edge effects extended beyond our edge transects. We fitted models describing richness, total abundance and individual species abundance. Low-density housing developments provided suitable habitat for most arboreal mammals. In contrast, high-density housing developments had lower species richness, total abundance and individual species abundance, but supported the highest abundances of an urban adapter (Trichosurus vulpecula). We did not find the predicted gradual decline in species abundance. Of four species analysed, three exhibited no response to the proximity of urban boundaries, but spilled over into adjacent urban habitat to differing extents. One species (Petaurus australis) had an extended negative response to urban boundaries, suggesting that urban development has impacts beyond 300 m into adjacent forest. Our empirical work demonstrates that high-density housing developments have negative effects on both community and species level responses, except for one urban adapter. We developed a new predictive model of edge effects based on our results and the literature. To predict animal responses across edges, our framework integrates for first time: (1) habitat quality/preference, (2) species response with the proximity to the adjacent habitat, and (3) spillover extent/sensitivity to adjacent habitat boundaries. This framework will

  17. Urbanization impacts on mammals across urban-forest edges and a predictive model of edge effects.

    Directory of Open Access Journals (Sweden)

    Nélida R Villaseñor

    Full Text Available With accelerating rates of urbanization worldwide, a better understanding of ecological processes at the wildland-urban interface is critical to conserve biodiversity. We explored the effects of high and low-density housing developments on forest-dwelling mammals. Based on habitat characteristics, we expected a gradual decline in species abundance across forest-urban edges and an increased decline rate in higher contrast edges. We surveyed arboreal mammals in sites of high and low housing density along 600 m transects that spanned urban areas and areas turn on adjacent native forest. We also surveyed forest controls to test whether edge effects extended beyond our edge transects. We fitted models describing richness, total abundance and individual species abundance. Low-density housing developments provided suitable habitat for most arboreal mammals. In contrast, high-density housing developments had lower species richness, total abundance and individual species abundance, but supported the highest abundances of an urban adapter (Trichosurus vulpecula. We did not find the predicted gradual decline in species abundance. Of four species analysed, three exhibited no response to the proximity of urban boundaries, but spilled over into adjacent urban habitat to differing extents. One species (Petaurus australis had an extended negative response to urban boundaries, suggesting that urban development has impacts beyond 300 m into adjacent forest. Our empirical work demonstrates that high-density housing developments have negative effects on both community and species level responses, except for one urban adapter. We developed a new predictive model of edge effects based on our results and the literature. To predict animal responses across edges, our framework integrates for first time: (1 habitat quality/preference, (2 species response with the proximity to the adjacent habitat, and (3 spillover extent/sensitivity to adjacent habitat boundaries. This

  18. Vertical stratification of ichneumonid wasp communities: the effects of forest structure and life-history traits.

    Science.gov (United States)

    Di Giovanni, Filippo; Cerretti, Pierfilippo; Mason, Franco; Minari, Emma; Marini, Lorenzo

    2015-10-01

    Parasitoid wasp communities of the canopy of temperate forests are still largely unexplored. Very little is known about the community composition of parasitoids between canopy and understory and how much of this difference is related to forest structure or parasitoid biological strategies. In this study we investigated upon the difference in the community composition of the parasitic wasps Ichneumonidae between canopy and understory in a lowland temperate forest in northern Italy. We used general linear models to test whether parasitic strategy modifies species vertical stratification and the effect of forest structure. We also tested differences in β-diversity between canopy and understory traps and over time within single forest layers. We found that stand basal area was positively related to species richness, suggesting that the presence of mature trees can influence local wasp diversity, providing a higher number of microhabitats and hosts. The ichneumonid community of the canopy was different from that of the understory, and the β-diversity analysis showed higher values for the canopy, due to a higher degree of species turnover between traps. In our analyses, the vertical stratification was different between groups of ichneumonids sharing different parasitic strategies. Idiobiont parasitoids of weakly or deeply concealed hosts were more diverse in the understory than in the canopy while parasitoids of spiders were equally distributed between the two layers. Even though the ichneumonid community was not particularly species-rich in the canopy of the temperate forests, the extension of sampling to that habitat significantly increased the number of species recorded. © 2014 Institute of Zoology, Chinese Academy of Sciences.

  19. Effect of different tree mortality patterns on stand development in the forest model SIBYLA

    Directory of Open Access Journals (Sweden)

    Trombik Jiří

    2016-09-01

    Full Text Available Forest mortality critically affects stand structure and the quality of ecosystem services provided by forests. Spruce bark beetle (Ips typographus generates rather complex infestation and mortality patterns, and implementation of such patterns in forest models is challenging. We present here the procedure, which allows to simulate the bark beetle-related tree mortality in the forest dynamics model Sibyla. We explored how sensitive various production and stand structure indicators are to tree mortality patterns, which can be generated by bark beetles. We compared the simulation outputs for three unmanaged forest stands with 40, 70 and 100% proportion of spruce as affected by the disturbance-related mortality that occurred in a random pattern and in a patchy pattern. The used tree species and age class-specific mortality rates were derived from the disturbance-related mortality records from Slovakia. The proposed algorithm was developed in the SQLite using the Python language, and the algorithm allowed us to define the degree of spatial clustering of dead trees ranging from a random distribution to a completely clustered distribution; a number of trees that died in either mode is set to remain equal. We found significant differences between the long-term developments of the three investigated forest stands, but we found very little effect of the tested mortality modes on stand increment, tree species composition and diversity, and tree size diversity. Hence, our hypothesis that the different pattern of dead trees emergence should affect the competitive interactions between trees and regeneration, and thus affect selected productivity and stand structure indicators was not confirmed.

  20. Effects of wildlife forestry on abundance of breeding birds in bottomland hardwood forests of Louisiana

    Science.gov (United States)

    Norris, Jennifer L.; Chamberlain, Michael J.; Twedt, Daniel J.

    2009-01-01

    Effects of silvicultural activities on birds are of increasing interest because of documented national declines in breeding bird populations for some species and the potential that these declines are in part due to changes in forest habitat. Silviculturally induced disturbances have been advocated as a means to achieve suitable forest conditions for priority wildlife species in bottomland hardwood forests. We evaluated how silvicultural activities on conservation lands in bottomland hardwood forests of Louisiana, USA, influenced species-specific densities of breeding birds. Our data were from independent studies, which used standardized point-count surveys for breeding birds in 124 bottomland hardwood forest stands on 12 management areas. We used Program DISTANCE 5.0, Release 2.0 (Thomas et al. 2006) to estimate density for 43 species with > 50 detections. For 36 of those species we compared density estimates among harvest regimes (individual selection, group selection, extensive harvest, and no harvest). We observed 10 species with similar densities in those harvest regimes compared with densities in stands not harvested. However, we observed 10 species that were negatively impacted by harvest with greater densities in stands not harvested, 9 species with greater densities in individual selection stands, 4 species with greater densities in group selection stands, and 4 species with greater densities in stands receiving an extensive harvest (e.g., > 40% canopy removal). Differences in intensity of harvest influenced densities of breeding birds. Moreover, community-wide avian conservation values of stands subjected to individual and group selection, and stands not harvested, were similar to each other and greater than that of stands subjected to extensive harvest that removed > 40% canopy cover. These results have implications for managers estimating breeding bird populations, in addition to predicting changes in bird communities as a result of prescribed and future

  1. Effects of dams and geomorphic context on riparian forests of the Elwha River, Washington

    Science.gov (United States)

    Shafroth, Patrick B.; Perry, Laura G; Rose, Chanoane A; Braatne, Jeffrey H

    2016-01-01

    Understanding how dams affect the shifting habitat mosaic of river bottomlands is key for protecting the many ecological functions and related goods and services that riparian forests provide and for informing approaches to riparian ecosystem restoration. We examined the downstream effects of two large dams on patterns of forest composition, structure, and dynamics within different geomorphic contexts and compared them to upstream reference conditions along the Elwha River, Washington, USA. Patterns of riparian vegetation in river segments downstream of the dams were driven largely by channel and bottomland geomorphic responses to a dramatically reduced sediment supply. The river segment upstream of both dams was the most geomorphically dynamic, whereas the segment between the dams was the least dynamic due to substantial channel armoring, and the segment downstream of both dams was intermediate due to some local sediment supply. These geomorphic differences were linked to altered characteristics of the shifting habitat mosaic, including older forest age structure and fewer young Populus balsamifera subsp. trichocarpa stands in the relatively static segment between the dams compared to more extensive early-successional forests (dominated by Alnus rubra and Salix spp.) and pioneer seedling recruitment upstream of the dams. Species composition of later-successional forest communities varied among river segments as well, with greater Pseudotsuga menziesii and Tsuga heterophylla abundance upstream of both dams, Acer spp. abundance between the dams, and P. balsamifera subsp. trichocarpa and Thuja plicata abundance below both dams. Riparian forest responses to the recent removal of the two dams on the Elwha River will depend largely on channel and geomorphic adjustments to the release, transport, and deposition of the large volume of sediment formerly stored in the reservoirs, together with changes in large wood dynamics.

  2. Effect of Forest Walking on Autonomic Nervous System Activity in Middle-Aged Hypertensive Individuals: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Chorong Song

    2015-03-01

    Full Text Available There has been increasing attention on the therapeutic effects of the forest environment. However, evidence-based research that clarifies the physiological effects of the forest environment on hypertensive individuals is lacking. This study provides scientific evidence suggesting that a brief forest walk affects autonomic nervous system activity in middle-aged hypertensive individuals. Twenty participants (58.0 ± 10.6 years were instructed to walk predetermined courses in forest and urban environments (as control. Course length (17-min walk, walking speed, and energy expenditure were equal between the forest and urban environments to clarify the effects of each environment. Heart rate variability (HRV and heart rate were used to quantify physiological responses. The modified semantic differential method and Profile of Mood States were used to determine psychological responses. The natural logarithm of the high-frequency component of HRV was significantly higher and heart rate was significantly lower when participants walked in the forest than when they walked in the urban environment. The questionnaire results indicated that, compared with the urban environment, walking in the forest increased “comfortable”, “relaxed”, “natural” and “vigorous” feelings and decreased “tension-anxiety,” “depression,” “anxiety-hostility,” “fatigue” and “confusion”. A brief walk in the forest elicited physiological and psychological relaxation effects on middle-aged hypertensive individuals.

  3. Effects of post-harvest treatments on high-elevation forests in the North Cascade Range, Washington.

    Science.gov (United States)

    Ella Elman; David L. Peterson

    2005-01-01

    We studied the effects of post-harvest treatments on regeneration and forest composition 13-27 years following harvest in high-elevation forests of the North Cascade Range, Washington. Eighteen sites encompassing three common post-harvest treatments were examined at elevations ranging from 830 m to 1460 m. Treatments included: (1) sites broadcast burned and planted...

  4. Unintended Consequences: Effect of the American Jobs Creation Act Reforestation Incentives on Family Forest Owners in the South

    Science.gov (United States)

    John L. Greene; Thomas J. Straka

    2008-01-01

    Abstract: The American Jobs Creation Act of 2004 rewrote the reforestation tax incentives available to private forest owners. Owners can now deduct outright reforestation costs up to $10,000 per year for each qualified timber property and amortize any additional amount over 8 tax years. To assess the economic effect of the new incentives on forest owners, the authors...

  5. Effects of creating two forest structures and using prescribed fire on coarse woody debris in northeastern California, USA

    Science.gov (United States)

    Fabian C. C. Uzoh; Carl N. Skinner

    2009-01-01

    Little is known about the dynamics of coarse woody debris (CWD) in forests that were originally characterized by frequent, low-moderate intensity fires. We investigated effects of prescribed burning at the Blacks Mountain Experimental Forest in northeastern California following creation of two stand structure conditions: 1) high structural diversity (HiD) that included...

  6. Interactive effects of air pollution and climate change on forest ecosystems in the United States: current understanding and future scenarios

    Science.gov (United States)

    Andrzej Bytnerowicz; Mark Fenn; Steven McNulty; Fengming Yuan; Afshin Pourmokhtarian; Charles Driscoll; Tom Meixner

    2013-01-01

    A review of the current status of air pollution and climate change (CC) in the United States from a perspective of their impacts on forest ecosystems is provided. Ambient ozone (O3) and nitrogen (N) deposition have important and widespread ecological impacts in U.S. forests. Effects of sulphurous (S) air pollutants and other trace pollutants have...

  7. Harvest-related edge effects on prey availability and foraging of hooded warblers in a bottomland hardwood forest

    Science.gov (United States)

    John C. Kilgo

    2005-01-01

    The effects of harvest-created canopy gaps in bottomland hardwood forests on arthropod abundance and, hence, the foraging ecology of birds are poorly understood. I predicted that arthropod abundance would be high near edges of group-selection harvest gaps and lower in the surrounding forest, and that male Hooded Warblers (Wilsonia citrina) foraging...

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

    Science.gov (United States)

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

    1996-01-01

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

  9. Effect of soil compaction and organic matter removal on two earthworm populations and some soil properties in a hardwood forest

    Science.gov (United States)

    D. Jordan; V. C. Hubbard; F., Jr. Ponder; E. C. Berry

    1999-01-01

    Earthworms can alter the physical, chemical, and biological properties of a forest ecosystem. Any physical manipulation to the soil ecosystem may, in turn, affect the activities and ecology of earthworms. The effects of organic matter removal (logs and forest floor) and soil compaction on earthworm activities were measured in a central hardwood region (oakhickory)...

  10. Birch mixture in spruce forest - a method to reduce the effects of acidification?

    International Nuclear Information System (INIS)

    Maartensson, Kristina.

    1996-01-01

    Acidification has lately been focus of increased attention in the business, industrial and public sectors. One measure that can prevent further acidification is the liming of forest soils. Another strategy would be to increase the admixture of deciduous tree species in conifer forest. This paper deals with the latter problem. From ecological and economical standpoints, the tree species offering the most advantageous admixture in Sweden would be birch, Betula pendula, and Norway spruce, Picea abies. Birch trees help to increase soil pH, while decreasing atmospheric deposition and protecting young spruce seedling from frost. The use of birch admixture need to be 50% or more to get required effect. This will lead to a reduction in spruce wood production. This need not to be a problem, however, since birch pulp will probably become more valuable in the future. The admixed forests have a higher biological diversity and are of greater value for recreation. Although spruce production on acidified sited is still high, further atmospheric deposition could lead to declines in production. Forest soils will eventually sustain serious damage if acid deposition continues to increase, which will require new alternatives for wood production be found. A high admixture of birch can offer a temporary respite if emission and deposition continue, but cannot completely compensate for the acidifying effects of present deposition levels. 26 refs, 2 figs

  11. Effects of drainage and forest management practices on hydraulic conductivity of wetland soils

    Science.gov (United States)

    R.W. Skaggs; Amatya Chescheir; J.D. Diggs

    2008-01-01

    Continuous records of water table elevations and flow rates from drained forested lands were analysed to determine field effective hydraulic conductivity (K) of a mineral (Deloss s.l.) and an organic (Belhaven muck) soil. K of the top 90 cm of Deloss under mature pine was 60 m/day, which is 20 to 30 times that published for this series. Harvest had a minor effect on K...

  12. Effects of Interannual Climate Variability in Secondary Forests and Crops Under Traditional and Alternative Shifting Cultivation

    Science.gov (United States)

    Sa, T. D.; Guild, L. S.; Carvalho, C. J.; Potter, C. S.; Wickel, A. J.; Brienza, S.; Kato, M. A.; Kato, O.

    2002-12-01

    Regenerating forests play an important role in long-term carbon sequestration and sustainable landuse as they act as potentially important carbon and nutrient sinks during the shifting agriculture fallow period. The long-term functioning of secondary forests (capoeira) is increasingly threatened by a shortening fallow period during shifting cultivation due to demographic pressures and associated increased vulnerability to severe climatic events. Declining productivity and functioning of fallow forests of shifting cultivation combined with progressive loss of nutrients by successive burning and cropping activities has resulted in declining agricultural productivity. In addition to the effects of intense land use practices, droughts associated with El Ni¤o events are becoming more frequent and severe in moist tropical forests and negative effects on capoeira productivity could be considerable. In Igarape-Acu (near Belem, Para), we hypothesize that experimental alternative landuse/clearing practices (mulching and fallow vegetation improvement by planting with fast-growing leguminous tree species) may make capoeira and crops more resilient to the effects of agricultural pressures and drought through 1) increased biomass, soil organic matter and associated increase in soil water storage, and nutrient retention and 2) greater rooting depth of trees planted for fallow improvement. This experimental practice (mechanized chop-and-mulch with fallow improvement) has resulted in increased soil moisture during the cropping phase, reduced loss of nutrients and organic matter, and higher rates of secondary-forest biomass accumulation. We present preliminary data on water relations during the dry season of 2001 in capoeira and crops for both traditional slash-and-burn and alternative chop-and-mulch practices. These data will be used to test IKONOS data for the detection of moisture status differences. The principal goal of the research is to determine the extent to which capoeira

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-03-25

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

  14. Liming with powdered oil-shale ash in a heavily damaged forest ecosystem. 2.The effect on forest condition in a pine stand

    International Nuclear Information System (INIS)

    Terasmaa, T.; Pikk, J.

    1995-01-01

    First years after the treatment (in 1987) of forest soil with mineral fertilizers and powdered oil-shale ash in a heavily damaged 50-year-old Scots pine ecosystem showed a comparatively small effect (B<0.95) of liming on the stand characters. However, in comparison with the effect of only NPK fertilization on the volume growth and the health state of trees, liming (NPK+oil-shale ash) tended to increase the positive influence of fertilizers. Under the influence of oil-shale ash the mortality of the trees was lower, the density of the stand rose more, and the mean radial increment of trees was by 26% greater than after the NPK treatment without a lime agent. On the whole, the effect of oil-shale ash liming on the growth and health condition of the pine stand was not high. However, the first results of its experimental use on mineral forest soil cannot serve as the basis for essential conclusions. Still, the results give us some assurance to continue our experimental work with powdered oil-shale ash in forests with the purpose of regulating the high acidity of forest soils in some sites to gain positive shifts in the forest life. Taking into account the low price of the powdered oil-shale ash and the plentiful resources of this liming material in Estonia, even a small trend towards an improvement of forest condition on poor sandy soils would be a satisfactory final result of the work. It is essential to note that oil-shale ash is not only a simple liming material, but also a lime fertilizer consisting of numerous chemical elements necessary for plant growth. 2 tabs., 3 figs., 18 refs

  15. An integrated analysis of the effects of past land use on forest herb colonization at the landscape scale

    Science.gov (United States)

    Verheyen, K.; Guntenspergen, Glenn R.; Biesbrouck, B.; Hermy, M.

    2003-01-01

    A framework that summarizes the direct and indirect effects of past land use on forest herb recolonization is proposed, and used to analyse the colonization patterns of forest understorey herbaceous species in a 360-ha mixed forest, grassland and arable landscape in the Dijle river valley (central Belgium).Fine-scale distribution maps were constructed for 14 species. The species were mapped in 15 946 forest plots and outside forests (along parcel margins) in 5188 plots. Forest stands varied in age between 1 and more than 224 years. Detailed land-use history data were combined with the species distribution maps to identify species-specific colonization sources and to calculate colonization distances.The six most frequent species were selected for more detailed statistical analysis.Logistic regression models indicated that species frequency in forest parcels was a function of secondary forest age, distance from the nearest colonization source and their interaction. Similar age and distance effects were found within hedgerows.In 199 forest stands, data about soils, canopy structure and the cover of competitive species were collected. The relative importance of habitat quality and spatio-temporal isolation for the colonization of the forest herb species was quantified using structural equation modelling (SEM), within the framework proposed for the effects of past land use.The results of the SEM indicate that, except for the better colonizing species, the measured habitat quality variables are of minor importance in explaining colonization patterns, compared with the combination of secondary forest age and distance from colonization sources.Our results suggest the existence of a two-stage colonization process in which diaspore availability determines the initial pattern, which is affected by environmental sorting at later stages.

  16. Effects of warming on the structure and function of a boreal black spruce forest

    Energy Technology Data Exchange (ETDEWEB)

    Stith T.Gower

    2010-03-03

    A strong argument can be made that there is a greater need to study the effect of warming on boreal forests more than on any other terrestrial biome. Boreal forests, the second largest forest biome, are predicted to experience the greatest warming of any forest biome in the world, but a process-based understanding of how warming will affect the structure and function of this economically and ecologically important forest biome is lacking. The effects of warming on species composition, canopy structure and biogeochemical cycles are likely to be complex; elucidating the underlying mechanisms will require long-term whole-ecosystem manipulation to capture all the complex feedbacks (Shaver et al. 2000, Rustad et al. 2001, Stromgren 2001). The DOE Program for Ecosystem Research funded a three year project (2002-2005) to use replicated heated chambers on soil warming plots in northern Manitoba to examine the direct effects of whole-ecosystem warming. We are nearing completion of our first growing season of measurements (fall 2004). In spite of the unforeseen difficulty of installing the heating cable, our heating and irrigation systems worked extremely well, maintaining environmental conditions within 5-10% of the specified design 99% of the time. Preliminary data from these systems, all designed and built by our laboratory at the University of Wisconsin, support our overall hypothesis that warming will increase the carbon sink strength of upland boreal black spruce forests. I request an additional three years of funding to continue addressing the original objectives: (1) Examine the effect of warming on phenology of overstory, understory and bryophyte strata. Sap flux systems and dendrometer bands, monitored by data loggers, will be used to quantify changes in phenology and water use. (2) Quantify the effects of warming on nitrogen and water use by overstory, understory and bryophytes. (3) Compare effects of warming on autotrophic respiration and above- and belowground

  17. Effects of fire and harvest on soil respiration in a mixed-conifer forest

    Science.gov (United States)

    Dore, S.; Fry, D.; Stephens, S.

    2012-12-01

    Forest ecosystems, and in particular forest soils, constitute a major reservoir of global terrestrial carbon and soil respiration is the largest carbon loss from these ecosystems. Disturbances can affect soil respiration, causing physical and chemical changes in soil characteristics, adding both, above and belowground necromass, and changing microclimatic conditions. This could signify an important and long term carbon loss, even higher than the carbon directly removed by the harvest or during fire. These losses need to be included when quantifying the net carbon balance of forests. We measured the impacts of prescribed fire and clear-cut tree harvest on soil respiration in a mixed-conifer forest in the central Sierra Nevada. The prescribed fire treatment was implemented in 2002 and again in 2009. Four areas were clear-cut harvested in 2010. In half of these units the soils were mechanically ripped to reduce soil compaction, a common practice in the Sierra Nevada industrial forest lands. Soil respiration was measured using two different techniques: the chamber method and the gradient method. Soil respiration was affected by treatments in two different ways. First, treatments changed soil temperature and soil water content, the main abiotic factors controlling soil respiration. The clear cut and the prescribed fire treatments created higher maximum soil temperature and more available soil water content, environmental conditions favorable to soil respiration. However, the loss of trees and thus fine roots, and the decrease of soil litter and organic layers, because of their combustion or removal, had a negative effect on soil respiration that was stronger than the positive effect due to more favorable post disturbance environmental conditions. Soil respiration rates remained steady 1-2 years after treatments and no increase or spikes of soil respiration were measured after treatments. Continuous measurements of CO2 concentrations at different soil depths improved our

  18. Analysis of effectiveness of three forest interventionist techniques and proposal of a new and integrated model of forest restoration.

    Science.gov (United States)

    Castelli, Karen Regina; Barreto, Mariana Gregorio; Francesconi, Wendy; Dalla Valle, Leandro; Mondelli, Giulliana; Abilio, Fernanda Maria; da Silva, Alexandre Marco

    2015-01-01

    We assessed the efficacy of three different forest intervention techniques, in terms of phytosociological and edaphic responses, that were implemented in 2007. In a farm where trees are planted and managed for cellulose production as well as set aside for environmental conservation, four stands were analysed: three of them were considered degraded and were managed using different intervention techniques (transposition, perch, and abandonment), and a fourth stand comprising pristine vegetation was considered a control (reference). Floristic and phytosociology data were collected in three 10 × 10 m plots established in each stand. Also, a total of 48 soil samples were collected to analyse physical and chemical attributes of the topsoil for the different stands. In terms of biodiversity, all the treatments showed significantly lower values when compared to the reference area. However, the soils in all the treatment and reference stands are similar in terms of physical and chemical attributes. Taking into account the specificities of each restoration technique, we verified that the integrated use of a set of management practices, constituted by the (1) abandonment of the area and (2) following a selective killing of the eucalyptus, is the most suitable and promising model to provide fast and effective restoration in terms of environmental indicators.

  19. Carbon stocks estimates for French forests. COST E21 Workshop. Contribution of forests and forestry to mitigate greenhouse effects. Joensuu (Finland. 28-30 Sep 2000

    Directory of Open Access Journals (Sweden)

    Dupouey J.L.

    2000-01-01

    Full Text Available This paper gives a short description of the data and methods used for inventorying the carbon stocks in the biomass and soil pools in metropolitan French forests. The data concerning the biomass pools are measured by the French National Forest Inventory (NFI while data necessary to estimate the soil carbon pools are obtained from the 16 x 16 km soil inventory of the International Cooperative Programme on Assessment and Monitoring of Air Pollution Effects on Forests in the UN/ECE. Some of the problems raised by the implementation of the Kyoto protocol articles 3.3 and 3.4 in France are discussed and a preliminary estimate of the changes in relevant carbon storage is given.

  20. Behavioral effects of type II pyrethroid cyhalothrin in rats

    International Nuclear Information System (INIS)

    Righi, D. Abbud; Palermo-Neto, J.

    2003-01-01

    Synthetic pyrethroids such as cyhalothrin are extensively used in agriculture for the control of a broad range of ectoparasites in farm animals. It has been suggested that type II pyrethroids might induce anxiogenic-like effects in laboratory animals. The present study was undertaken to investigate a possible anxiogenic-like outcome of cyhalothrin in rats. Adult male rats were orally dosed for 7 days with 1.0, 3.0, or 7.0 mg/kg/day of cyhalothrin, present in a commercial formulation (Grenade Coopers do Brazil S.A.). The neurobehavioral changes induced by cyhalothrin as well as those produced on corticosterone serum levels were measured 24 h after the last treatment. Picrotoxin (1.0 mg/kg) was also acutely used as a positive control for anxiety. Results showed that cyhalothrin: (1) induced some signs and symptoms of intoxication that included salivation, tremors, and liquid feces; (2) reduced total locomotor activity in the open-field; (3) reduced the percentage of time spent in open-field central zones; (4) increased immobility time in the open-field; (5) reduced the percentage of time spent in plus-maze open arms exploration; (6) reduced the time spent in social interactions, and (7) increased the levels of serum corticosterone. The behavioral changes reported for cyhalothrin (3.0 mg/kg/day) were similar of those induced by picrotoxin. The no effect level dose obtained for cyhalothrin in this study was 1.0 mg/kg/day. These results provide experimental evidence that cyhalothrin induces anxiety-like symptoms, with this effect being dose-related. Thus, anxiety must be included among the several signs and symptoms of pesticide intoxication

  1. Effects of hurricane disturbance on stream water concentrations and fluxes in eight tropical forest watersheds of the Luquillo Experimental Forest, Puerto Rico.

    Science.gov (United States)

    DOUGLAS. A. SCHAEFER; WILLIAM H. McDOWELL; FREDRICK N. SCATENA; CLYDE E. ASBURY

    2000-01-01

    Stream water chemistry responds substantially to watershed disturbances, but hurricane effects have not been extensively investigated in tropical regions. This study presents a long-term (2.5±11 y) weekly record of stream water chemistry on eight forested watersheds (catchment basins) in the Luquillo Mountains of Puerto Rico. This includes a period before and at least...

  2. Effect of hepatocyte growth factor and angiotensin II on rat cardiomyocyte hypertrophy

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Ai-Lan [Department of Cardiology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou (China); Ou, Cai-Wen [The Fourth Affiliated Hospital of Guangzhou Medical University, Guangzhou (China); He, Zhao-Chu [Department of Cardiology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou (China); Liu, Qi-Cai [Experimental Medical Research Center, Guangzhou Medical University, Guangzhou (China); Dong, Qi [Department of Physiology, Guangzhou Medical University, Guangzhou (China); Chen, Min-Sheng [Guangzhou Key Laboratory of Cardiovascular Disease, Guangzhou Institute of Cardiovascular Disease, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou (China)

    2012-10-15

    Angiotensin II (Ang II) plays an important role in cardiomyocyte hypertrophy. The combined effect of hepatocyte growth factor (HGF) and Ang II on cardiomyocytes is unknown. The present study was designed to determine the effect of HGF on cardiomyocyte hypertrophy and to explore the combined effect of HGF and Ang II on cardiomyocyte hypertrophy. Primary cardiomyocytes were isolated from neonatal rat hearts and cultured in vitro. Cells were treated with Ang II (1 µM) alone, HGF (10 ng/mL) alone, and Ang II (1 µM) plus HGF (10 ng/mL) for 24, 48, and 72 h. The amount of [{sup 3}H]-leucine incorporation was then measured to evaluate protein synthesis. The mRNA levels of β-myosin heavy chain and atrial natriuretic factor were determined by real-time PCR to evaluate the presence of fetal phenotypes of gene expression. The cell size of cardiomyocytes was also studied. Ang II (1 µM) increased cardiomyocyte hypertrophy. Similar to Ang II, treatment with 1 µM HGF promoted cardiomyocyte hypertrophy. Moreover, the combination of 1 µM Ang II and 10 ng/mL HGF clearly induced a combined pro-hypertrophy effect on cardiomyocytes. The present study demonstrates for the first time a novel, combined effect of HGF and Ang II in promoting cardiomyocyte hypertrophy.

  3. A multi-sites analysis on the ozone effects on Gross Primary Production of European forests.

    Science.gov (United States)

    Proietti, C; Anav, A; De Marco, A; Sicard, P; Vitale, M

    2016-06-15

    Ozone (O3) is both a greenhouse gas and a secondary air pollutant causing adverse impacts on forests ecosystems at different scales, from cellular to ecosystem level. Specifically, the phytotoxic nature of O3 can impair CO2 assimilation that, in turn affects forest productivity. This study aims to evaluate the effects of tropospheric O3 on Gross Primary Production (GPP) at 37 European forest sites during the time period 2000-2010. Due to the lack of carbon assimilation data at O3 monitoring stations (and vice-versa) this study makes a first attempt to combine high resolution MODIS Gross Primary Production (GPP) estimates and O3 measurement data. Partial Correlations, Anomalies Analysis and the Random Forests Analysis (RFA) were used to quantify the effects of tropospheric O3 concentration and its uptake on GPP and to evaluate the most important factors affecting inter-annual GPP changes. Our results showed, along a North-West/South-East European transect, a negative impact of O3 on GPP ranging from 0.4% to 30%, although a key role of meteorological parameters respect to pollutant variables in affecting GPP was found. In particular, meteorological parameters, namely air temperature (T), soil water content (SWC) and relative humidity (RH) are the most important predictors at 81% of test sites. Moreover, it is interesting to highlight a key role of SWC in the Mediterranean areas (Spanish, Italian and French test sites) confirming that, soil moisture and soil water availability affect vegetation growth and photosynthesis especially in arid or semi-arid ecosystems such as the Mediterranean climate regions. Considering the pivotal role of GPP in the global carbon balance and the O3 ability to reduce primary productivity of the forests, this study can help in assessing the O3 impacts on ecosystem services, including wood production and carbon sequestration. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. The effect of natural and planted forest stands on soil fertility in the Hyrcanian region, Iran

    Directory of Open Access Journals (Sweden)

    RAZIYEH RAFEIE JAHED

    2014-10-01

    Full Text Available Rafeie Jahed R, Hosseini SM, Kooch Y. 2014. The effect of natural and planted forest stands on soil fertility in the Hyrcanian region, Iran. Biodiversitas 15: 206-214. In the present work, we studied the effect of natural and planted forest stands on soil fertility in the Hyrcanian region of northern Iran. Natural forest stands (including Acer velutinum Bioss., Zelkova carpinifolia (Pall, Parrotia persica (DC. C.A.Mey, Quercus castaneifolia C.A. Mey., Carpinus betulus L, Mixed planted stand (including Acer velutinum, Ulmus carpinifolia G. Suckow Quercus castaneifolia C.A. Mey, Carpinus betulus L., Tilia begonifolia Scop. Subsp. caucasia (Rupr. Loria; maple (Acer velutinum Bioss plantation, pine (Pinus taeda L. plantation and also clear-cut region (control were considered in this research. Soil samples were collected at two different depths, i.e., 0-15 and 15-30 cm, and characterized with respect to organic carbon (C, total nitrogen (N, available nutrient elements (P, K, Ca and Mg; pH and soil texture. The results showed that the highest amount of total N was found in mixed plantation. The highest amount of available P was detected in maple plantation and pine plantation had the highest available K and organic C than other treatments. The highest and the lowest available Ca and Mg were found in natural forest and control area, respectively. In addition, it was observed that nutrients accumulate in upper layers of the soil. Hardwood stands have been more successful than the conifers stands, so this should be considered in the sustainable management of forests.

  5. Effects of an exotic plant invasion on native understory plants in a tropical dry forest.

    Science.gov (United States)

    Prasad, Ayesha E

    2010-06-01

    The dry forests of southern India, which are endangered tropical ecosystems and among the world's most important tiger (Panthera tigris) habitats, are extensively invaded by exotic plants. Yet, experimental studies exploring the impacts of these invasions on native plants in these forests are scarce. Consequently, little is known about associated implications for the long-term conservation of tigers and other biodiversity in these habitats. I studied the impacts of the exotic plant Lantana camara on understory vegetation in a dry-forest tiger habitat in southern India. I compared the richness, composition, and abundance of tree seedlings, herbs, and shrubs and the abundance of grass among plots in which Lantana was cleared or left standing. These plots were distributed across two blocks-livestock free and livestock grazed. Removal of Lantana had an immediate positive effect on herb-shrub richness in the livestock-free block, but had no effect on that of tree seedlings in either livestock block. Tree-seedling and herb-shrub composition differed significantly between Lantana treatment and livestock block, and Lantana removal significantly decreased survival of tree seedlings. Nevertheless, the absence of trees, in any stage between seedling and adult, indicates that Lantana may stall tree regeneration. Lantana removal decreased the abundance of all understory strata, probably because forage plants beneath Lantana are less accessible to herbivores, and plants in Lantana-free open plots experienced greater herbivory. Reduced access to forage in invaded habitats could negatively affect ungulate populations and ultimately compromise the ability of these forests to sustain prey-dependent large carnivores. Additional research focused on understanding and mitigating threats posed by exotic plants may be crucial to the long-term protection of these forests as viable tiger habitats.

  6. Effects of biotic disturbances on forest carbon cycling in the United States and Canada

    Science.gov (United States)

    Vogelmann, James E.; Allen, Craig D.; Hicke, Jeffrey A.; Desai, Ankur R.; Dietze, Michael C.; Hall, Ronald J.; ,

    2012-01-01

    Forest insects and pathogens are major disturbance agents that have affected millions of hectares in North America in recent decades, implying significant impacts to the carbon (C) cycle. Here, we review and synthesize published studies of the effects of biotic disturbances on forest C cycling in the United States and Canada. Primary productivity in stands was reduced, sometimes considerably, immediately following insect or pathogen attack. After repeated growth reductions caused by some insects or pathogens or a single infestation by some bark beetle species, tree mortality occurred, altering productivity and decomposition. In the years following disturbance, primary productivity in some cases increased rapidly as a result of enhanced growth by surviving vegetation, and in other cases increased slowly because of lower forest regrowth. In the decades following tree mortality, decomposition increased as a result of the large amount of dead organic matter. Net ecosystem productivity decreased immediately following attack, with some studies reporting a switch to a C source to the atmosphere, and increased afterward as the forest regrew and dead organic matter decomposed. Large variability in C cycle responses arose from several factors, including type of insect or pathogen, time since disturbance, number of trees affected, and capacity of remaining vegetation to increase growth rates following outbreak. We identified significant knowledge gaps, including limited understanding of carbon cycle impacts among different biotic disturbance types (particularly pathogens), their impacts at landscape and regional scales, and limited capacity to predict disturbance events and their consequences for carbon cycling. We conclude that biotic disturbances can have major impacts on forest C stocks and fluxes and can be large enough to affect regional C cycling. However, additional research is needed to reduce the uncertainties associated with quantifying biotic disturbance effects on

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

    Science.gov (United States)

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

    2013-07-01

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

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

    International Nuclear Information System (INIS)

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

    1991-07-01

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

  9. Effectiveness of Mangrove Forest as Coastal Protection along the West Coast of Northern Peninsular Malaysia

    Directory of Open Access Journals (Sweden)

    Hashim Ahmad Mustafa

    2017-01-01

    Full Text Available The effectiveness of mangrove forest as coastal protection was evidenced during Indian Ocean Tsunami (IOT on 24th December 2004. This paper presents the assessment on the characteristics and distribution of the mangrove forest along three northern states (Perlis, Kedah and Perak affected by IOT 2004. At each site, the characteristics of individual tree were recorded including their species, height and diameter at breast height (DBH. A total of 52 matured trees were sampled that encompassing four species; A. marina (n=21, A. alba (n=7, R. mucronata (n=20 and R. apiculata (n=4 were found with A. marina as the dominant species. The zonation of mangrove forest along the northern states revealed that Avicenniacea inhabits the frontal area. The field survey also discovered that mangrove forest along the states was generally insufficient to protect the coastal area from future tsunami. There were several rehabilitation programs that had been implemented, but not all replanting efforts were successful. Outcomes from this research provided invaluable findings for the optimum replanting scheme to ensure acceptable level of protection along Malaysia’s coastline.

  10. Effects of long-term rainfall decline on the structure and functioning of Hawaiian forests

    Science.gov (United States)

    Barbosa, Jomar M.; Asner, Gregory P.

    2016-09-01

    Climate change is altering the dynamics of terrestrial vegetation, with consequences for the functioning of Earth’s biomes and the provisioning of ecosystem services. Changes in forest dynamics due to drought events or short-term drying trends have been described at different ecological scales, but few observational studies have determined the relative effects of short- and long-term precipitation trends (e.g. decade and century, respectively) on forest canopy structure and functioning. Using gridded annual precipitation maps from 1920 to 2012, and temporal data from airborne light detection and ranging (LiDAR) and MODIS Enhanced Vegetation Index (EVI), we present evidence for a large-scale decline in forest canopy volume (area vs. height) and greenness (a metric of photosynthetic function) driven by a long-term drying trend on Hawaii island. Decreases in canopy greenness were observed in step with shorter-term (10 y) precipitation declines, but decreases in greenness were two-fold greater where longer-term (∼100 y) precipitation declines had occurred. Canopy volume mainly reduced where long-term precipitation declines occurred. We conclude that long-term precipitation trends critically impact forest canopy structure and functioning, which likely has cascading consequences for numerous ecological processes such as subcanopy light availability, species interactions, carbon storage, and animal habitat.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1991-07-01

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

  12. OWR/RTNS-II low exposure spectral effects experiment

    International Nuclear Information System (INIS)

    Heinisch, H.L.; Atkin, S.D.

    1983-01-01

    Miniature flat tensile specimens of Fe, Cu, 316 stainless steel and A302B pressure vessel steel are to be irradiated to a range of fluences in RTNS-II and the Omega West Reactor at 90 0 C and 290 0 C. The first RTNS-II irradiation is now in progress, and preparations are being made for the first Omega West Reactor irradiation. Some specimens are also being irradiated at room temperature in RTNS-II. The flat tensile specimens lend themselves to a variety of measurements, many of which, including the tensile tests, can be done on the same specimen

  13. Liming with powdered oil-shale ash in a heavily damaged forest ecosystem. 1.The effect on forest soil in a pine stand

    International Nuclear Information System (INIS)

    Terasmaa, T.; Sepp, S.

    1994-01-01

    A fertilization and liming experiment with mineral fertilizers and powdered oil-shale ash was carried out in a heavily damaged 50-year-old Scots pine ecosystem in South Estonia. In Estonia, where electric power is produced mainly in big oil-shale-fired power plants, huge quantities of SO 2 are flying into the atmosphere through the chimneys of the plants. However, it is characteristic of Estonia that simultaneously with comparatively high SO 2 pollution the proton load has been quite low because of big amounts of alkali c ash emitted together with SO 2 into the atmosphere through the chimneys of the thermal power plants. Therefore, acid rains are not frequent in Estonia. Acid precipitation here is caused mainly by SO 2 released in the central part of Europe. In Estonia acid rains are most frequently registered in the southern area of the country. At times rains with pH values below 5.1 (even 4.0 and lower) have been registered there. This is also the region where quite severely damaged pine forests can be found. As a rule, these forests grow on acid sandy soils poor in nutrients and bases. The aim of the present study was to investigate the possibility of using oil shale ash as a liming agent in a forest ecosystem for protecting forest soils from acidification and, together with some mineral fertilizers, for improving the health of injured pine stands. In Estonia the most easily available liming agent is powdered oil-shale ash, which has been widely used as a lime fertilizer for agricultural crops but so far has not been tested for liming forests on mineral soils. The comparison of the present study with the liming experiments carried out with limestone in Finland shows that the effect of oil-shale ash treatment of acid sandy soils to raise pH values and to reduce other characteristics of soil acidity was more effective than limestone liming of mineral soils in Finnish forests. The present study demonstrates that powdered oil-shale ash is highly effective in short

  14. Effects of climate changes on forest ecosystems. Final report

    International Nuclear Information System (INIS)

    Lasch, P.; Lindner, M.; Bellmann, K.

    1995-08-01

    The report evalutates the current state of knowledge on the effects of site-related climate factors (temperature sum in the vegetation period, frost, water supply and arid phases) on the growth and distribution of different tree species. The effects of increasing CO2 levels in the atmosphere are discussed as well. ( orig./MG) [de

  15. Micellar effect on metal-ligand complexes of Co(II, Ni(II, Cu(II and Zn(II with citric acid

    Directory of Open Access Journals (Sweden)

    Nageswara Rao Gollapalli

    2009-12-01

    Full Text Available Chemical speciation of citric acid complexes of Co(II, Ni(II, Cu(II and Zn(II was investigated pH-metrically in 0.0-2.5% anionic, cationic and neutral micellar media. The primary alkalimetric data were pruned with SCPHD program. The existence of different binary species was established from modeling studies using the computer program MINIQUAD75. Alkalimetric titrations were carried out in different relative concentrations (M:L:X = 1:2:5, 1:3:5, 1:5:3 of metal (M to citric acid. The selection of best chemical models was based on statistical parameters and residual analysis. The species detected were MLH, ML2, ML2H and ML2H2. The trend in variation of stability constants with change in mole fraction of the medium is explained on the basis of electrostatic and non-electrostatic forces. Distributions of the species with pH at different compositions of micellar media are also presented.

  16. Adsorption of Cu(II), Zn(II), Cd(II) and Pb(II) by dead Avena fatua biomass and the effect of these metals on their growth.

    Science.gov (United States)

    Areco, María Mar; Saleh-Medina, Leila; Trinelli, María Alcira; Marco-Brown, Jose Luis; Dos Santos Afonso, María

    2013-10-01

    The biosorption of copper(II), zinc(II), cadmium(II) and lead(II) from aqueous solutions by dead Avena fatua biomass and the effect of these metals on the growth of this wild oat were investigated. Pseudo-first- and second-order and intra-particle diffusion models were applied to describe the kinetic data and to evaluate the rate constants. The adsorption kinetics of all the metals follows a pseudo-second-order model. The adsorption capacity was determined, and the Freundlich and Langmuir models were applied. The experimental data obtained for all the metals are best described by the Langmuir model. A. fatua was characterized using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and zeta potential. The results obtained evidence the presence of Zn(II), Cu(II), Cd(II) or Pb(II) on the surface of the weed. The growth of A. fatua was affected by the presence of all metals. The decrease in the growth rate with increasing metal concentration was more noticeable for zinc. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Relationship between spectral reflectance and leaf area index in needleleaf forest: The effect of three-dimensional forest structure and clumping

    International Nuclear Information System (INIS)

    Kobayashi, H.

    2008-01-01

    Toward the reliable estimation of leaf area index (LAI) and fraction of absorbed photosynthetically active radiation (FAPAR), the relationship between LAI/FAPAR and bidirectional reflectance factor (BRF) at the top of canopy should be accurately modeled by the radiation transfer models. These relationships vary with the forest landscape due to its horizontal heterogeneity and needles clumping within shoot. In this study, the effect of the forest heterogeneity on the relationships between BRF and LAI, and NDVI and LAI/FAPAR were examined through the three-dimensional radiative transfer simulation, and were compared with the results from one-dimensional radiative transfer simulation. In addition to the simulation, limitation of one-dimensional radiative transfer simulation was evaluated. The results showed that BRF at red and near infrared, and NDVI had large variations with different forest landscape under the same LAI conditions. However the relationship between NDVI and LAI, and NDVI and FAPAR derived from dense canopy condition were quite similar to the results from one-dimensional model. If we add the shoot clumping effect in one dimensional radiative transfer model as a universal parameter for three-dimensional effect of the forest, one dimensional radiative transfer model can work well for the BRF simulation in spatially heterogeneous landscape except higher LAI conditions

  18. Physiological and psychological effects of forest therapy on middle-aged males with high-normal blood pressure.

    Science.gov (United States)

    Ochiai, Hiroko; Ikei, Harumi; Song, Chorong; Kobayashi, Maiko; Takamatsu, Ako; Miura, Takashi; Kagawa, Takahide; Li, Qing; Kumeda, Shigeyoshi; Imai, Michiko; Miyazaki, Yoshifumi

    2015-02-25

    Time spent walking and relaxing in a forest environment ("forest bathing" or "forest therapy") has well demonstrated anti-stress effects in healthy adults, but benefits for ill or at-risk populations have not been reported. The present study assessed the physiological and psychological effects of forest therapy (relaxation and stress management activity in the forest) on middle-aged males with high-normal blood pressure. Blood pressure and several physiological and psychological indices of stress were measured the day before and approximately 2 h following forest therapy. Both pre- and post-treatment measures were conducted at the same time of day to avoid circadian influences. Systolic and diastolic blood pressure (BP), urinary adrenaline, and serum cortisol were all significantly lower than baseline following forest therapy (pforest therapy. These results highlight that forest is a promising treatment strategy to reduce blood pressure into the optimal range and possibly prevent progression to clinical hypertension in middle-aged males with high-normal blood pressure.

  19. Effects of Coffee Management Intensity on Composition, Structure, and Regeneration Status of Ethiopian Moist Evergreen Afromontane Forests

    Science.gov (United States)

    Hundera, Kitessa; Aerts, Raf; Fontaine, Alexandre; Van Mechelen, Maarten; Gijbels, Pieter; Honnay, Olivier; Muys, Bart

    2013-03-01

    The effect of arabica coffee management intensity on composition, structure, and regeneration of moist evergreen Afromontane forests was studied in three traditional coffee-management systems of southwest Ethiopia: semiplantation coffee, semiforest coffee, and forest coffee. Vegetation and environmental data were collected in 84 plots from forests varying in intensity of coffee management. After controlling for environmental variation (altitude, aspect, slope, soil nutrient availability, and soil depth), differences in woody species composition, forest structure, and regeneration potential among management systems were compared using one way analysis of variance. The study showed that intensification of forest coffee cultivation to maximize coffee production negatively affects diversity and structure of Ethiopian moist evergreen Afromontane forests. Intensification of coffee productivity starts with the conversion of forest coffee to semiforest coffee, which has significant negative effects on tree seedling abundance. Further intensification leads to the conversion of semiforest to semiplantation coffee, causing significant diversity losses and the collapse of forest structure (decrease of stem density, basal area, crown closure, crown cover, and dominant tree height). Our study underlines the need for shade certification schemes to include variables other than canopy cover and that the loss of species diversity in intensively managed coffee systems may jeopardize the sustainability of coffee production itself through the decrease of ecosystem resilience and disruption of ecosystem services related to coffee yield, such as pollination and pest control.

  20. Modelling effects of forest disturbance history on carbon balance: a deep learning approach using Landsat-time series.

    Science.gov (United States)

    Besnard, S.; Carvalhais, N.; Clevers, J.; Dutrieux, L.; Gans, F.; Herold, M.; Reichstein, M.; Jung, M.

    2017-12-01

    Forests play a crucial role in the global carbon (C) cycle, covering about 30% of the planet's terrestrial surface, accounting for 50% of plant productivity, and storing 45% of all terrestrial C. As such, forest disturbances affect the balance of terrestrial C dioxide (CO 2 ) exchange, with the potential of releasing large amounts of C into the atmosphere. Understanding and quantifying the effect of forest disturbance on terrestrial C metabolism is critical for improving forest C balance estimates and predictions. Here we combine remote sensing, climate, and eddy-covariance (EC) data to study forest land surface-atmosphere C fluxes at more than 180 sites globally. We aim to enhance understanding of C balance in forest ecosystems by capturing the ecological carry-over effect of disturbance historyon C fluxes. Our objectives are to (1) characterize forest disturbance history through the full temporal depth of the Landsat time series (LTS); and (2) to investigate lag and carry-over effects of forest dynamics and climate on ecosystem C fluxes using a data-driven recurrent neural network(RNN). The resulting data-driven model integrates carry-over effects of the system, using LTS, ecosystem productivity, and several abiotic factors. In this study, we show that our RNN algorithm is able to effectively calculate realistic seasonal, interannual, and across-site C flux variabilities based on EC, LTS, and climate data. In addition, our results demonstrate that a deep learning approach with embedded dynamic memory effects offorest dynamics is able to better capture lag and carry-over effects due to soil-vegetation feedback compared to a classic approach considering only the current condition of the ecosystem. Our study paves the way to produce accurate, high resolution carbon fluxes maps, providing morecomprehensive monitoring, mapping, and reporting of the carbon consequences of forest change globally.

  1. A systematic review of randomized controlled trials on curative and health enhancement effects of forest therapy

    Directory of Open Access Journals (Sweden)

    Kamioka H

    2012-07-01

    Full Text Available Hiroharu Kamioka,1 Kiichiro Tsutani,2 Yoshiteru Mutoh,3 Takuya Honda,4 Nobuyoshi Shiozawa,5 Shinpei Okada,6 Sang-Jun Park,6 Jun Kitayuguchi,7 Masamitsu Kamada,8 Hiroyasu Okuizumi,9 Shuichi Handa91Faculty of Regional Environment Science, Tokyo University of Agriculture, Tokyo, 2Department of Drug Policy and Management, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, 3Todai Policy Alternatives Research Institute, The University of Tokyo, Tokyo, 4Japanese Society for the Promotion of Science, Tokyo, 5Food Labeling Division, Consumer Affairs Agency, Cabinet Office, Government of Japan, Tokyo, 6Physical Education and Medicine Research Foundation, Nagano, 7Physical Education and Medicine Research Center Unnan, Shimane, 8Department of Environmental and Preventive Medicine, Shimane University School of Medicine, Shimane, 9Mimaki Onsen (Spa Clinic, Tomi City, Nagano, JapanObjective: To summarize the evidence for curative and health enhancement effects through forest therapy and to assess the quality of studies based on a review of randomized controlled trials (RCTs.Study design: A systematic review based on RCTs.Methods: Studies were eligible if they were RCTs. Studies included one treatment group in which forest therapy was applied. The following databases – from 1990 to November 9, 2010 – were searched: MEDLINE via PubMed, CINAHL, Web of Science, and Ichushi-Web. All Cochrane databases and Campbell Systematic Reviews were also searched up to November 9, 2010.Results: Two trials met all inclusion criteria. No specific diseases were evaluated, and both studies reported significant effectiveness in one or more outcomes for health enhancement. However, the results of evaluations with the CONSORT (Consolidated Standards of Reporting Trials 2010 and CLEAR NPT (A Checklist to Evaluate a Report of a Nonpharmacological Trial checklists generally showed a remarkable lack of description in the studies. Furthermore, there was a

  2. Long-term effects of timber harvesting on forest soil communities and their catabolic capacity

    Science.gov (United States)

    Mohn, W. W.

    2016-12-01

    We examined the effect of forest harvesting on metagenomes of soil communities in ecozones across North America. The overall effect of harvesting on community composition was very small relative to major differences between soil horizons and among geographically distinct ecozones. However, in some ecozones, harvesting substantially altered bacterial and fungal community composition and diminished the genetic potential for biomass decomposition while increasing the potential for nitrogen cycling. Stable isotope probing identified populations involved in hemicellulose and cellulose decomposition. Known cellulolytic organisms were found in the organic soil layer, while novel cellulolytic organisms were identified in the mineral soil layer. Lignolytic populations identified were mainly bacterial, and metagenomics analysis identified lignin degradation enzymes in the genomes of some of these populations. In some ecozones, cellulolytic and hemicellulolytic populations were substantially impacted by harvesting. Soil carbon, nitrogen and pH were related to the relative susceptibility of forest soil communities in the different ecozones to harvesting impacts.

  3. TCP Final Report: Measuring the Effects of Stand Age and Soil Drainage on Boreal Forest

    Energy Technology Data Exchange (ETDEWEB)

    Michael L. Goulden

    2007-05-02

    forests in our study region have remained largely constant over the last 20 years after accounting for the effects of stand age and succession (McMillen et al. in review).

  4. Effects of logging on roadless space in intact forest landscapes of the Congo Basin.

    Science.gov (United States)

    Kleinschroth, Fritz; Healey, John R; Gourlet-Fleury, Sylvie; Mortier, Frédéric; Stoica, Radu S

    2017-04-01

    Forest degradation in the tropics is often associated with roads built for selective logging. The protection of intact forest landscapes (IFL) that are not accessible by roads is high on the biodiversity conservation agenda and a challenge for logging concessions certified by the Forest Stewardship Council (FSC). A frequently advocated conservation objective is to maximize the retention of roadless space, a concept that is based on distance to the nearest road from any point. We developed a novel use of the empty-space function - a general statistical tool based on stochastic geometry and random sets theory - to calculate roadless space in a part of the Congo Basin where road networks have been expanding rapidly. We compared the temporal development of roadless space in certified and uncertified logging concessions inside and outside areas declared IFL in 2000. Inside IFLs, road-network expansion led to a decrease in roadless space by more than half from 1999 to 2007. After 2007, loss leveled out in most areas to close to 0 due to an equilibrium between newly built roads and abandoned roads that became revegetated. However, concessions in IFL certified by FSC since around 2007 continuously lost roadless space and reached a level comparable to all other concessions. Only national parks remained mostly roadless. We recommend that forest-management policies make the preservation of large connected forest areas a top priority by effectively monitoring - and limiting - the occupation of space by roads that are permanently accessible. © 2016 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.

  5. Effects of fire on major forest ecosystem processes: an overview.

    Science.gov (United States)

    Chen, Zhong

    2006-09-01

    Fire and fire ecology are among the best-studied topics in contemporary ecosystem ecology. The large body of existing literature on fire and fire ecology indicates an urgent need to synthesize the information on the pattern of fire effects on ecosystem composition, structure, and functions for application in fire and ecosystem management. Understanding fire effects and underlying principles are critical to reduce the risk of uncharacteristic wildfires and for proper use of fire as an effective management tool toward management goals. This overview is a synthesis of current knowledge on major effects of fire on fire-prone ecosystems, particularly those in the boreal and temperate regions of the North America. Four closely related ecosystem processes in vegetation dynamics, nutrient cycling, soil and belowground process and water relations were discussed with emphases on fire as the driving force. Clearly, fire can shape ecosystem composition, structure and functions by selecting fire adapted species and removing other susceptible species, releasing nutrients from the biomass and improving nutrient cycling, affecting soil properties through changing soil microbial activities and water relations, and creating heterogeneous mosaics, which in turn, can further influence fire behavior and ecological processes. Fire as a destructive force can rapidly consume large amount of biomass and cause negative impacts such as post-fire soil erosion and water runoff, and air pollution; however, as a constructive force fire is also responsible for maintaining the health and perpetuity of certain fire-dependent ecosystems. Considering the unique ecological roles of fire in mediating and regulating ecosystems, fire should be incorporated as an integral component of ecosystems and management. However, the effects of fire on an ecosystem depend on the fire regime, vegetation type, climate, physical environments, and the scale of time and space of assessment. More ecosystem

  6. El Nino effects on southern California kelp forest communities

    Energy Technology Data Exchange (ETDEWEB)

    Tegner, M.J.; Dayton, P.K.

    1987-01-01

    Coincident with the Christmas season in the Peruvian and Equadorian coastal areas, the normally cold water of the north-flowing Peru Current is displaced by a warm, southward current associated with a decrease in nutrients and a temporary reduction in fishing success. This is the generic ''El Nino'', a brief seasonal anomaly ending by March or April. Occasionally, however, the warm current strengthens and persists for a year or more, usually with a catastrophic effect on marine ecosystems. This paper reviews the effects of this massive oceanic phenomenon on the nearshore kelp communities of the southern California Bight.

  7. Effects of the control method (Goč variety in selection forest management in Western Serbia

    Directory of Open Access Journals (Sweden)

    Medarević M.

    2010-01-01

    Full Text Available The control method, one of the most reliable methods of selection forest management, has been applied in selection forests of western Serbia in a somewhat modified form (Goč variety for fifty years. This paper analyzes the effects of the control method, i.e. its Goč variety, in the period from 1960/70 - 2000. It is based on the data of five successive complete inventories of the Forest Management Unit (FMU 'Tara', whose high selection forest of spruce, fir and beech (Piceo-Abieti-Fagetum subass. typicum trees on diluvium, brown and illimerised soil on limestone, and on limestone in formation with hornfels, are the best quality and the most spacious forests in the Management Class MC 491/1. The effects were monitored through the changes in the distribution of the number of trees and volume per diameter classes, separately for fir as the protagonist of the selection structure, and collectively at the level of a compartment, a typical representative of MC 491/1. Also, the analysis included the changes in the number of trees, volume, current volume increment, yield, and number of recruited trees per unit area (1 ha by tree species in MC 491/1, occupying an area of 2,648.78 ha. The study results show that in the study period the average volume in MC 491/1 increased by 18.8%, the percentage of conifers increased from 66.0% to 78.5%, and the bearer of the changes was fir. The volume of the mean fir tree increased by 35.9% and it attained 1.086 m3. The volume increment increased by 15.7%. The selection structure of conifers was satisfactory, but there were problems with beech regeneration, in its stable presence and in its achievement of the targeted structure. The number of trees per unit area (1 ha decreased, which in the long run could have detrimental consequences, but the sustainability in general was satisfactory. The levels of regeneration and recruitment were satisfactory. The health of the trees was improved; the stands were healthy, vital

  8. Effects of forest-based bioenergy feedstock production on shallow groundwater quality of a drained forest soil.

    Science.gov (United States)

    Cacho, Julian F; Youssef, Mohamed A; Chescheir, George M; Wayne Skaggs, R; Appelboom, Timothy W; Leggett, Zakiya H; Sucre, Eric B; Nettles, Jami E; Arellano, Consuelo

    2018-03-05

    Managed forests in southern U.S. are a potential source of lignocellulosic biomass for biofuel production. Changes in management practices to optimize biomass production may impact the quality of waters draining to nutrient-sensitive waters in coastal plain regions. We investigated shallow groundwater quality effects of intercropping switchgrass (Panicum virgatum L.) with managed loblolly pine (Pinus taeda L.) to produce bioenergy feedstock and quality sawtimber in a poorly drained soil of eastern North Carolina, U.S.A. Treatments included PINE (traditional pine production), PSWITCH (pine-switchgrass intercropped), SWITCH (switchgrass monoculture) and REF (mature loblolly pine stand). Each treatment was replicated three times on 0.8ha plots drained by parallel-open ditches, 1.0-1.2m deep and 100m apart. Water samples were collected monthly or more frequently after fertilizer application. Water samples were analyzed for organic nitrogen (ON), ammonium N (NH 4 + - N), and nitrite+nitrate N (NO 3 - + NO 2 - - N), ortohophosphate phosphorus (OP), and total organic carbon (TOC). Overall, PSWITCH did not significantly affect shallow groundwater quality relative to PINE and SWITCH. ON, NO 3 - + NO 2 - - N, and TOC concentrations in PSWITCH, PINE and SWITCH were substantially elevated during the two years after tree harvest and site establishment. The elevated nutrient concentrations at the beginning of the study were likely caused by a combination of rapid organic matter decomposition of the abundant supply of post-harvest residues, warming of exposed soil surfaces and reduction of plant nutrient uptake that can occur after harvesting, and pre-plant fertilization. Nutrient concentrations returned to background levels observed in REF during the third year after harvest. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Biomass production and nutrient cycling in Eucalyptus short rotation energy forests in New Zealand: II. Litter fall and nutrient return

    Energy Technology Data Exchange (ETDEWEB)

    Guo, L.B.; Sims, R.E.H. [Institute of Technology and Engineering, Massey University, Private Bag 11222, Palmerston North (New Zealand); Horne, D.J. [Institute of Natural Resources, Massey University, Private Bag 11222, Palmerston North (New Zealand)

    2006-05-15

    Litter fall and nutrient return via the litter fall were measured during the first 3-yr rotation of three Eucalyptus short rotation forest species (E. botryoides, E. globulus and E. ovata) irrigated with meatworks effluent compared with no irrigation. Up to 13.4 oven-dry t/ha/yr of annual litter fall was recorded with nutrient returns of up to 159kgN/ha/yr, 9kgP/ha/yr, 28kgK/ha/yr, 125kgCa/ha/yr, 22kgMg/ha/yr, and 32kgMn/ha/yr. Effluent irrigation increased the litter fall and the return of some nutrients. More litter fall with higher nutrient return was found under E. globulus than under the other two species. However, the amounts of litter fall and nutrient return were highly dependent on the degree of biomass production and nutrient uptake. During the 3-yr period, up to 20% of the total above ground biomass produced was in the form of litter, and via the litter fall, up to 24% of the total N uptake was returned to the soil surface. (author)

  10. Alberta biodiversity monitoring program - monitoring effectiveness of sustainable forest management planning.

    Science.gov (United States)

    Stadt, J John; Schieck, Jim; Stelfox, Harry A

    2006-10-01

    A conceptual model of sustainable forest management is described based on three connected and necessary components: Policy/Strategic Planning, Operational Planning, and Effectiveness Monitoring/Science. Alberta's proposed Forest Management Planning Standard is described as an example of operational planning. The standard utilizes coarse and fine filter approaches to conserving biodiversity and sets requirements for implementation monitoring. The Alberta Biodiversity Monitoring Program (ABMP) is described as an example of effectiveness monitoring supporting Operational Planning. The ABMP is a rigorous science-based initiative that is being developed to monitor and report on biodiversity status and trends throughout the province of Alberta, Canada. The basic survey design consists of 1656 sites, 20 km apart, evenly spaced on a grid pattern across Alberta. Sites will be sampled over a five-year period at a rate of 350 sites/year. Standardized sampling protocols will be used to cover a broad range of species and habitat elements within terrestrial and aquatic environments, as well as broader landscape-level features. Trends and associations detected by ABMP products will be validated through cause-effect research. ABMP focuses research on critical issues and informs both operational planning and the development of policy and strategic-level plans. The Alberta Forest Management Planning Standard and the ABMP are described as key components to implementing resource planning based on ecosystem management principles.

  11. Effects of policosanol on postmenopausal women with type II hypercholesterolemia.

    Science.gov (United States)

    Castaño, G; Más, R; Fernández, L; Fernández, J C; Illnait, J; López, L E; Alvarez, E

    2000-06-01

    This randomized, double-blind, placebo-controlled study was conducted to investigate the efficacy, safety and tolerability of policosanol, a cholesterol-lowering drug purified from sugar-cane wax, in postmenopausal women with type II hypercholesterolemia. A total of 244 women who had experienced the menopause and showed elevated serum total cholesterol and low-density lipoprotein cholesterol (LDL-C) levels despite 6 weeks on a standard lipid-lowering diet were randomized to receive placebo or policosanol 5 mg/day for 12 weeks, after which the dose was doubled to 10 mg/day for the next 12 weeks. Policosanol (5 and 10 mg/day) significantly lowered LDL-C levels (17.7% and 25.2%, respectively) and total cholesterol (12.6% and 16.7%, respectively), as well as the ratios of LDL-C to high-density lipoprotein cholesterol (HDL-C) (17.0% and 29.3%, respectively) and total cholesterol to HDL-C (16.7% and 27.2%, respectively), compared to the baseline and placebo; at the same time, policosanol significantly raised HDL-C levels by 16.5% and 29.3%, respectively. The drug was safe and well tolerated. No drug-related adverse events were observed, and even the extent of adverse events was less in the policosanol group than in the placebo group. Four serious adverse events occurred in the placebo group (one myocardial infarction, two cases of hypertensive status and one surgical intervention) compared to none in the policosanol group. In conclusion, policosanol is effective, safe and well tolerated in hypercholesterolemic postmenopausal women.

  12. [Effects of forest gap size and within-gap position on the microclimate in Pinus koraiensis-dominated broadleaved mixed forest].

    Science.gov (United States)

    Feng, Jing; Duan, Wen-Biao; Chen, Li-Xin

    2012-07-01

    HOBO automatic weather stations were installed in the central parts and at the south, north, east, and west edges of large, medium, and small gaps in a Pinus koraiensis-dominated broadleaved mixed forest in Xiaoxing' anling Mountains to measure the air temperature, relative humidity, and photosynthetic photon flux density (PPFD) in these locations and the total radiation and precipitation in the gap centres from June to September 2010, taking the closed forest stand and open field as the controls. The differences in the microclimate between various size forest gaps and between the gap centers and their edges as well as the variations of the microclimatic factors over time were analyzed, and the effects of sunny and overcast days on the diurnal variations of the microclimatic factors within forest gaps were compared, aimed to offer basic data and practice reference for gap regeneration and sustainable management of Pinus koraiensis-dominated broadleaved mixed forest. The PPFD was decreased in the order of large gap, medium gap, and small gap. For the same gaps, the PPFD in gap centre was greater than that in gap edge. The mean monthly air temperature and total radiation in gap centres were declined in the sequence of July, June, August, and September, and the amplitudes of the two climatic factors were decreased in the order of open field, large gap, medium gap, small gap, and closed forest stand. The mean monthly relative humidity in gap centres dropped in the order of August, July, September, and June, and the amplitude of this climatic factor was decreased in the sequence of closed forest stand, small gap, medium gap, large gap, and open field. The total and monthly precipitations for the three different size gaps and open field during measurement period generally decreased in the order of open field, large gap, medium gap, small gap, and closed forest stand. In sunny days, the variations of PPFD, air temperature, and relative humidity were greater in large gap

  13. Reference stand condition - Effects of Thinning on Forest Structure important to the recovery of ESA-listed species

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This study evaluates the effects of thinning regimes designed to accelerate the development of late-successional forest structure for the benefit of salmon and other...

  14. European mixed forests

    DEFF Research Database (Denmark)

    Bravo-Oviedo, Andres; Pretzsch, Hans; Ammer, Christian

    2014-01-01

    Aim of study: We aim at (i) developing a reference definition of mixed forests in order to harmonize comparative research in mixed forests and (ii) review the research perspectives in mixed forests. Area of study: The definition is developed in Europe but can be tested worldwide. Material...... and Methods: Review of existent definitions of mixed forests based and literature review encompassing dynamics, management and economic valuation of mixed forests. Main results: A mixed forest is defined as a forest unit, excluding linear formations, where at least two tree species coexist at any...... developmental stage, sharing common resources (light, water, and/or soil nutrients). The presence of each of the component species is normally quantified as a proportion of the number of stems or of basal area, although volume, biomass or canopy cover as well as proportions by occupied stand area may be used...

  15. Secondary Forest as a counterbalance on the deforestation effects: its role on evapotranspiration and water use efficiency

    Science.gov (United States)

    Von Randow, Rita C. S.; Tomasella, Javier; Von Randow, Celso; Araujo, Alessandro C.; Manzi, Antonio O.

    2017-04-01

    Since the 70's, the Amazon basin is under constant pressure first because of agricultural expansion, and recently also because of resources extraction. The conversion of pristine forest to other types of land cover as pasture and agriculture, affects the local water balance diminishing the evapotranspiration and increasing the discharge. Those changes can buffer the climate change effects and vice-versa. On the other hand, secondary forest growth resulting from abandoned deforested areas presents higher evaporative fraction (Giambelluca, 2002), leading to higher evapotranspiration rates than pristine forests, what can compensate the effects of deforestation on energy and water balances. In this work we will show four years of eddy flux measurements of a pristine forest and of a secondary growth about 20 years old, located in Central Amazonia, comparing the evapotranspiration and water use efficiency of both sites. The innovative aspect of the present work is the measurement of fluxes above a secondary growth forest in a relatively advanced stage. The measurements of eddy covariance are in accordance with the increase of evaporative fraction with the age of secondary forest presented by Giambelluca (2002). The yearly evaporative fraction (ratio of energy used for evapotranspiration to net radiation) on the primary forest was 0.74-0.81, while in the secondary forest it was 0.85-0.87. On the other hand, secondary forest shows a water use efficiency of 1.9 g C kg-1 H2O, while the pristine forest gives 2.9 g C kg-1 H2O.

  16. Transpiration and CO2 fluxes of a pine forest: modelling the undergrowth effect

    Directory of Open Access Journals (Sweden)

    V. Rivalland

    2005-02-01

    Full Text Available A modelling study is performed in order to quantify the relative effect of allowing for the physiological properties of an undergrowth grass sward on total canopy water and carbon fluxes of the Le-Bray forest (Les-Landes, South-western France. The Le-Bray forest consists of maritime pine and an herbaceous undergrowth (purple moor-grass, which is characterised by a low stomatal control of transpiration, in contrast to maritime pine. A CO2-responsive land surface model is used that includes responses of woody and herbaceous species to water stress. An attempt is made to represent the properties of the undergrowth vegetation in the land surface model Interactions between Soil, Biosphere, and Atmosphere, CO2-responsive, ISBA-A-gs. The new adjustment allows for a fairly different environmental response between the forest canopy and the understory in a simple manner. The model's simulations are compared with long term (1997 and 1998 micro-meteorological measurements over the Le-Bray site. The fluxes of energy, water and CO2, are simulated with and without the improved representation of the undergrowth vegetation, and the two simulations are compared with the observations. Accounting for the undergrowth permits one to improve the model's scores. A simple sensitivity experiment shows the behaviour of the model in response to climate change conditions, and the understory effect on the water balance and carbon storage of the forest. Accounting for the distinct characteristics of the undergrowth has a substantial and positive effect on the model accuracy and leads to a different response to climate change scenarios.

  17. Modelling Variable Fire Severity in Boreal Forests: Effects of Fire Intensity and Stand Structure.

    Science.gov (United States)

    Miquelajauregui, Yosune; Cumming, Steven G; Gauthier, Sylvie

    2016-01-01

    It is becoming clear that fires in boreal forests are not uniformly stand-replacing. On the contrary, marked variation in fire severity, measured as tree mortality, has been found both within and among individual fires. It is important to understand the conditions under which this variation can arise. We integrated forest sample plot data, tree allometries and historical forest fire records within a diameter class-structured model of 1.0 ha patches of mono-specific black spruce and jack pine stands in northern Québec, Canada. The model accounts for crown fire initiation and vertical spread into the canopy. It uses empirical relations between fire intensity, scorch height, the percent of crown scorched and tree mortality to simulate fire severity, specifically the percent reduction in patch basal area due to fire-caused mortality. A random forest and a regression tree analysis of a large random sample of simulated fires were used to test for an effect of fireline intensity, stand structure, species composition and pyrogeographic regions on resultant severity. Severity increased with intensity and was lower for jack pine stands. The proportion of simulated fires that burned at high severity (e.g. >75% reduction in patch basal area) was 0.80 for black spruce and 0.11 for jack pine. We identified thresholds in intensity below which there was a marked sensitivity of simulated fire severity to stand structure, and to interactions between intensity and structure. We found no evidence for a residual effect of pyrogeographic region on simulated severity, after the effects of stand structure and species composition were accounted for. The model presented here was able to produce variation in fire severity under a range of fire intensity conditions. This suggests that variation in stand structure is one of the factors causing the observed variation in boreal fire severity.

  18. Tropical secondary forest management influences frugivorous bat composition, abundance and fruit consumption in Chiapas, Mexico.

    Directory of Open Access Journals (Sweden)

    Ivar Vleut

    Full Text Available Most studies on frugivorous bat assemblages in secondary forests have concentrated on differences among successional stages, and have disregarded the effect of forest management. Secondary forest management practices alter the vegetation structure and fruit availability, important factors associated with differences in frugivorous bat assemblage structure, and fruit consumption and can therefore modify forest succession. Our objective was to elucidate factors (forest structural variables and fruit availability determining bat diversity, abundance, composition and species-specific abundance of bats in (i secondary forests managed by Lacandon farmers dominated by Ochroma pyramidale, in (ii secondary forests without management, and in (iii mature rain forests in Chiapas, Southern Mexico. Frugivorous bat species diversity (Shannon H' was similar between forest types. However, bat abundance was highest in rain forest and O. pyramidale forests. Bat species composition was different among forest types with more Carollia sowelli and Sturnira lilium captures in O. pyramidale forests. Overall, bat fruit consumption was dominated by early-successional shrubs, highest late-successional fruit consumption was found in rain forests and more bats consumed early-successional shrub fruits in O. pyramidale forests. Ochroma pyramidale forests presented a higher canopy openness, tree height, lower tree density and diversity of fruit than secondary forests. Tree density and canopy openness were negatively correlated with bat species diversity and bat abundance, but bat abundance increased with fruit abundance and tree height. Hence, secondary forest management alters forests' structural characteristics and resource availability, and shapes the frugivorous bat community structure, and thereby the fruit consumption by bats.

  19. Effects of angiotensin II and ionomycin on fluid and bicarbonate absorption in the rat proximal tubule

    International Nuclear Information System (INIS)

    Chatsudthipong, V.; Chan, Y.L.

    1986-01-01

    Microperfusion of proximal convoluted tubule(PCT) and peritubular capillaries was performed to examine the effects of angiotensin II(Ang II) and ionomycin on fluid and bicarbonate absorption. Bicarbonate was determined by microcalorimetry and C-14 inulin was used as a volume marker. The rates of bicarbonate absorption (JHCO 3 ) was 143 peq/min x mm and fluid absorption(Jv) was 2.70 nl/min x mm, when PCT and capillary perfusate contained normal Ringer solution. Addition of Ang II (10 -6 M) to the capillary perfusate caused reductions of JHCO 3 and Jv by 35%. A similar effect was observed when ionomycin was added to the capillary perfusate. Ang II antagonist, (Sar 1 , Ile 8 )-Angiotensin II(10 -6 M), completely blocked the inhibitory effect of Ang II on Jv and JHCO 3 . Removal of calcium from both luminal and capillary perfusate did not change the effect of Ang II on Jv and JHCO 3 . Our results indicate that Ang II inhibits the sodium-hydrogen exchanger in the proximal tubule via interacting with angiotensin receptor. The mechanism of Ang II action may involve mobilization of intracellular calcium

  20. Effect of forest clear cuts on plant–pollinator interactions: the case of three ericaceous subshrubs in Lithuanian pine forests

    Directory of Open Access Journals (Sweden)

    Remigijus Daubaras

    2017-03-01

    Full Text Available Managed boreal pine forests are subject to regular clear cuts causing significant disturbances to these ecosystems. It is believed that, to some extent, they resemble natural cycles of forest growth, decline, and regeneration and can benefit, e.g., mutualistic relations among plants and pollinators. To study the impact of forest management (clear cuts on pollinator visitation, we focused on three ericaceous plant species, Vaccinium myrtillus, V. vitis-idaea, and Calluna vulgaris, common elements of pine forest understory. Our observations, conducted in Lithuania, showed that there are no differences among control mature stands and clear cut areas in terms of visitation frequency for all three studied species. However, at least for C. vulgaris, a shift toward fly visits was observed in the clear cut site, showing that open areas are preferred habitats for these insects. Ants constituted an important share of visitors to flowers of V. myrtillus and C. vulgaris, suggesting their important role in reproduction of these plant species.