WorldWideScience

Sample records for complex forest site

  1. Canopy structure effects on the wind at a complex forested site

    DEFF Research Database (Denmark)

    Boudreault, Louis-Etienne; Bechmann, Andreas; Sørensen, Niels N.

    2014-01-01

    We investigated the effect of the canopy description in a Reynolds-averaged Navier-Stokes method based on key flow results from a complex forested site. The canopy structure in RANS is represented trough the frontal area of canopy elements per unit volume, a variable required as input in canopy...

  2. The choice of forest site for recreation

    DEFF Research Database (Denmark)

    Agimass, Fitalew; Lundhede, Thomas; Panduro, Toke Emil

    2017-01-01

    In this paper, we investigate the factors that can influence the site choice of forest recreation. Relevant attributes are identified by using spatial data analysis from a questionnaire asking people to indicate their most recent forest visits by pinpointing on a map. The main objectives of the s......In this paper, we investigate the factors that can influence the site choice of forest recreation. Relevant attributes are identified by using spatial data analysis from a questionnaire asking people to indicate their most recent forest visits by pinpointing on a map. The main objectives...... logit as well as a random parameter logit model. The variables that are found to affect the choice of forest site to a visit for recreation include: forest area, tree species composition, forest density, availability of historical sites, terrain difference, state ownership, and distance. Regarding...

  3. Complexity of Forest Management: Exploring Perceptions of Dutch Forest Managers

    Directory of Open Access Journals (Sweden)

    Jilske O. de Bruin

    2015-09-01

    Full Text Available Challenges of contemporary forest management are frequently referred to as complex. This article empirically studies complexity in forest management decision-making. In contrast to what is often assumed in the literature, this article starts by assuming that complexity does not just consist of an external descriptive element, but also depends on how decision-makers perceive the system at hand. This “perceived complexity” determines decision-making. We used a straightforward interpretation of perceived complexity using two criteria: the number of factors considered and the uncertainty perceived about these factors. The results show that Dutch forest managers generally consider forest management decision-making to be complicated (many factors to consider rather than complex (many uncertain factors to consider. Differences in sources of complexity confirm the individual character of perceived complexity. The factors perceived to be most relevant for decision-making (the forest itself, the organization’s objective, the cost of management, public opinion, national policies and laws, and new scientific insights and ideas are generally seen as rather certain, although “complexity reduction” may play a role that can adversely affect the quality of decision-making. Additional use of more open-ended, forward-looking methods, such as qualitative foresight tools, might enable addressing uncertainty and complexity, and thereby enhance decision-making in forest management to prepare for increasing complexity in the future.

  4. Mechanical site preparation for forest restoration

    Science.gov (United States)

    Magnus Lof; Daniel C. Dey; Rafael M. Navarro; Douglass F. Jacobs

    2012-01-01

    Forest restoration projects have become increasingly common around the world and planting trees is almost always a key component. Low seedling survival and growth may result in restoration failures and various mechanical site preparation techniques for treatment of soils and vegetation are important tools used to help counteract this. In this article, we synthesize the...

  5. Have we been successful? Monitoring horizontal forest complexity for forest restoration projects

    Science.gov (United States)

    Yvette L. Dickinson; Kristen A. Pelz; Emma Giles; Josh Howie

    2016-01-01

    Forest management today often seeks to restore ecological integrity and enhance human well-being by increasing forest complexity, resilience, and functionality. However, effective and financially expedient monitoring of forest complexity is challenging. In this study, we developed a practical and inexpensive technique to measure horizontal forest complexity....

  6. Ozone concentration characteristics at a high-elevation forest site

    Science.gov (United States)

    G. Wooldridge; K. Zeller; R. Musselman

    1997-01-01

    Atmospheric ozone concentrations have been monitored at a subalpine forest ecosystem site, 3180m above mean sea level (msl), and at a 2680m msl forest-steppe ecotone site 15km to the southeast. Ozone concentrations were monitored at three heights above the ground on a 30m tower at the higher elevation site, and on a 10m tower in a large meadow downwind of this site....

  7. Degraded tropical rain forests possess valuable carbon storage opportunities in a complex, forested landscape

    Science.gov (United States)

    Alamgir, Mohammed; Campbell, Mason J.; Turton, Stephen M.; Pert, Petina L.; Edwards, Will; Laurance, William F.

    2016-07-01

    Tropical forests are major contributors to the terrestrial global carbon pool, but this pool is being reduced via deforestation and forest degradation. Relatively few studies have assessed carbon storage in degraded tropical forests. We sampled 37,000 m2 of intact rainforest, degraded rainforest and sclerophyll forest across the greater Wet Tropics bioregion of northeast Australia. We compared aboveground biomass and carbon storage of the three forest types, and the effects of forest structural attributes and environmental factors that influence carbon storage. Some degraded forests were found to store much less aboveground carbon than intact rainforests, whereas others sites had similar carbon storage to primary forest. Sclerophyll forests had lower carbon storage, comparable to the most heavily degraded rainforests. Our findings indicate that under certain situations, degraded forest may store as much carbon as intact rainforests. Strategic rehabilitation of degraded forests could enhance regional carbon storage and have positive benefits for tropical biodiversity.

  8. Information system of forest growth and productivity by site quality type and elements of forest

    Science.gov (United States)

    Khlyustov, V.

    2012-04-01

    Information system of forest growth and productivity by site quality type and elements of forest V.K. Khlustov Head of the Forestry Department of Russian State Agrarian University named after K.A.Timiryazev doctor of agricultural sciences, professor The efficiency of forest management can be improved substantially by development and introduction of principally new models of forest growth and productivity dynamics based on regionalized site specific parameters. Therefore an innovative information system was developed. It describes the current state and gives a forecast for forest stand parameters: growth, structure, commercial and biological productivity depend on type of site quality. In contrast to existing yield tables, the new system has environmental basis: site quality type. The information system contains set of multivariate statistical models and can work at the level of individual trees or at the stand level. The system provides a graphical visualization, as well as export of the emulation results. The System is able to calculate detailed description of any forest stand based on five initial indicators: site quality type, site index, stocking, composition, and tree age by elements of the forest. The results of the model run are following parameters: average diameter and height, top height, number of trees, basal area, growing stock (total, commercial with distribution by size, firewood and residuals), live biomass (stem, bark, branches, foliage). The system also provides the distribution of mentioned above forest stand parameters by tree diameter classes. To predict the future forest stand dynamics the system require in addition the time slot only. Full set of forest parameters mention above will be provided by the System. The most conservative initial parameters (site quality type and site index) can be kept in the form of geo referenced polygons. In this case the system would need only 3 dynamic initial parameters (stocking, composition and age) to

  9. Returning biodiversity of rehabilitated forest on a coal mined site at Tanjung Enim, South Sumatra

    Directory of Open Access Journals (Sweden)

    HERY SUHARTOYO

    2012-01-01

    Full Text Available Suhartoyo H, Munawar A, Wiryono. 2012. Returning biodiversity of rehabilitated forest on a coal mined site at Tanjung Enim, South Sumatra. Biodiversitas 13: 13-17. Restoring disturbed mined land is challenging since the outcomes of various rehabilitation procedures on mined sites in terms of vegetation structure, composition and ecological function are not presently understood, especially in the developing countries. This study examined the mechanism of biodiversity recruitment, especially on structural attributes of an undisturbed forest community and rehabilitated forests of different ages on sites disturbed by coal-mining operations at Tanjung Enim, South Sumatra. Un-mined forest was characterised by complex structural features including a dense stand of trees in a range of size classes, an almost closed canopy, and a shrubby understorey. In contrast, young mined sites were characterised by a low density of woody stems, a relatively open canopy and herbaceous ground cover. Soil characteristics of rehabilitated site were progressing towards the reference site. The marked differences in structural complexity between unmined and mined sites suggest that it will will take very long time for the mined sites to recover into their original conditions. So, more restoration intervention will be needed to speed the recovery processes.

  10. Quantitative Analysis of Complex Tropical Forest Stands: A Review ...

    African Journals Online (AJOL)

    The importance of data analysis in quantitative assessment of natural resources remains significant in the sustainable management of complex tropical forest resources. Analyses of data from complex tropical forest stands have not been easy or clear due to improper data management. It is pivotal to practical researches ...

  11. Site productivity and forest carbon stocks in the United States: Analysis and implications for forest offset project planning

    Science.gov (United States)

    Coeli M. Hoover; James E. Smith

    2012-01-01

    The documented role of United States forests in sequestering carbon, the relatively low cost of forest-based mitigation, and the many co-benefits of increasing forest carbon stocks all contribute to the ongoing trend in the establishment of forest-based carbon offset projects. We present a broad analysis of forest inventory data using site quality indicators to provide...

  12. The role of forest site in fertilizer response

    Science.gov (United States)

    Raymond E. Leonard; Albert L. Leaf; John V. Berglund; John V. Berglund

    1972-01-01

    A major task in developing a successful forest-fertilization program is the proper assessment of the site conditions and organism relations so that efficient site-dependent fertilizer prescriptions may be developed for the most effective and least wasteful use of fertilizer additives.

  13. Complexity of Groundwater Contaminants at DOE Sites

    Energy Technology Data Exchange (ETDEWEB)

    Hazen, T.C.; Faybishenko, B.; Jordan, P.

    2010-12-03

    The U.S. Department of Energy (DOE) is responsible for the remediation and long-term stewardship of one of the world's largest groundwater contamination portfolios, with a significant number of plumes containing various contaminants, and considerable total mass and activity. As of 1999, the DOE's Office of Environmental Management was responsible for remediation, waste management, or nuclear materials and facility stabilization at 144 sites in 31 states and one U.S. territory, out of which 109 sites were expected to require long-term stewardship. Currently, 19 DOE sites are on the National Priority List. The total number of contaminated plumes on DOE lands is estimated to be 10,000. However, a significant number of DOE sites have not yet been fully characterized. The most prevalent contaminated media are groundwater and soil, although contaminated sediment, sludge, and surface water also are present. Groundwater, soil, and sediment contamination are present at 72% of all DOE sites. A proper characterization of the contaminant inventory at DOE sites is critical for accomplishing one of the primary DOE missions -- planning basic research to understand the complex physical, chemical, and biological properties of contaminated sites. Note that the definitions of the terms 'site' and 'facility' may differ from one publication to another. In this report, the terms 'site,' 'facility' or 'installation' are used to identify a contiguous land area within the borders of a property, which may contain more than one plume. The term 'plume' is used here to indicate an individual area of contamination, which can be small or large. Even though several publications and databases contain information on groundwater contamination and remediation technologies, no statistical analyses of the contaminant inventory at DOE sites has been prepared since the 1992 report by Riley and Zachara. The DOE Groundwater Data Base

  14. Urban Forest and Rural Cities: Multi-sited Households, Consumption Patterns, and Forest Resources in Amazonia

    Directory of Open Access Journals (Sweden)

    Christine Padoch

    2008-12-01

    Full Text Available In much of the Amazon Basin, approximately 70% of the population lives in urban areas and urbanward migration continues. Based on data collected over more than a decade in two long-settled regions of Amazonia, we find that rural-urban migration in the region is an extended and complex process. Like recent rural-urban migrants worldwide, Amazonian migrants, although they may be counted as urban residents, are often not absent from rural areas but remain members of multi-sited households and continue to participate in rural-urban networks and in rural land-use decisions. Our research indicates that, despite their general poverty, these migrants have affected urban markets for both food and construction materials. We present two cases: that of açaí palm fruit in the estuary of the Amazon and of cheap construction timbers in the Peruvian Amazon. We find that many new Amazonian rural-urban migrants have maintained some important rural patterns of both consumption and knowledge. Through their consumer behavior, they are affecting the areal extent of forests; in the two floodplain regions discussed, tree cover is increasing. We also find changes in forest composition, reflecting the persistence of rural consumption patterns in cities resulting in increased demand for and production of açaí and cheap timber species.

  15. Sleeping Sites and Latrines of Spider Monkeys in Continuous and Fragmented Rainforests: Implications for Seed Dispersal and Forest Regeneration

    Science.gov (United States)

    González-Zamora, Arturo; Arroyo-Rodríguez, Víctor; Oyama, Ken; Sork, Victoria; Chapman, Colin A.; Stoner, Kathryn E.

    2012-01-01

    Spider monkeys (Ateles geoffroyi) use sites composed of one or more trees for sleeping (sleeping sites and sleeping trees, respectively). Beneath these sites/trees they deposit copious amounts of dung in latrines. This behavior results in a clumped deposition pattern of seeds and nutrients that directly impacts the regeneration of tropical forests. Therefore, information on the density and spatial distribution of sleeping sites and latrines, and the characteristics (i.e., composition and structure) of sleeping trees are needed to improve our understanding of the ecological significance of spider monkeys in influencing forest composition. Moreover, since primate populations are increasingly forced to inhabit fragmented landscapes, it is important to assess if these characteristics differ between continuous and fragmented forests. We assessed this novel information from eight independent spider monkey communities in the Lacandona rainforest, Mexico: four continuous forest sites and four forest fragments. Both the density of sleeping sites and latrines did not differ between forest conditions. Latrines were uniformly distributed across sleeping sites, but the spatial distribution of sleeping sites within the areas was highly variable, being particularly clumped in forest fragments. In fact, the average inter-latrine distances were almost double in continuous forest than in fragments. Latrines were located beneath only a few tree species, and these trees were larger in diameter in continuous than fragmented forests. Because latrines may represent hotspots of seedling recruitment, our results have important ecological and conservation implications. The variation in the spatial distribution of sleeping sites across the forest indicates that spider monkeys likely create a complex seed deposition pattern in space and time. However, the use of a very few tree species for sleeping could contribute to the establishment of specific vegetation associations typical of the

  16. Sleeping sites and latrines of spider monkeys in continuous and fragmented rainforests: implications for seed dispersal and forest regeneration.

    Science.gov (United States)

    González-Zamora, Arturo; Arroyo-Rodríguez, Víctor; Oyama, Ken; Sork, Victoria; Chapman, Colin A; Stoner, Kathryn E

    2012-01-01

    Spider monkeys (Ateles geoffroyi) use sites composed of one or more trees for sleeping (sleeping sites and sleeping trees, respectively). Beneath these sites/trees they deposit copious amounts of dung in latrines. This behavior results in a clumped deposition pattern of seeds and nutrients that directly impacts the regeneration of tropical forests. Therefore, information on the density and spatial distribution of sleeping sites and latrines, and the characteristics (i.e., composition and structure) of sleeping trees are needed to improve our understanding of the ecological significance of spider monkeys in influencing forest composition. Moreover, since primate populations are increasingly forced to inhabit fragmented landscapes, it is important to assess if these characteristics differ between continuous and fragmented forests. We assessed this novel information from eight independent spider monkey communities in the Lacandona rainforest, Mexico: four continuous forest sites and four forest fragments. Both the density of sleeping sites and latrines did not differ between forest conditions. Latrines were uniformly distributed across sleeping sites, but the spatial distribution of sleeping sites within the areas was highly variable, being particularly clumped in forest fragments. In fact, the average inter-latrine distances were almost double in continuous forest than in fragments. Latrines were located beneath only a few tree species, and these trees were larger in diameter in continuous than fragmented forests. Because latrines may represent hotspots of seedling recruitment, our results have important ecological and conservation implications. The variation in the spatial distribution of sleeping sites across the forest indicates that spider monkeys likely create a complex seed deposition pattern in space and time. However, the use of a very few tree species for sleeping could contribute to the establishment of specific vegetation associations typical of the

  17. Sleeping sites and latrines of spider monkeys in continuous and fragmented rainforests: implications for seed dispersal and forest regeneration.

    Directory of Open Access Journals (Sweden)

    Arturo González-Zamora

    Full Text Available Spider monkeys (Ateles geoffroyi use sites composed of one or more trees for sleeping (sleeping sites and sleeping trees, respectively. Beneath these sites/trees they deposit copious amounts of dung in latrines. This behavior results in a clumped deposition pattern of seeds and nutrients that directly impacts the regeneration of tropical forests. Therefore, information on the density and spatial distribution of sleeping sites and latrines, and the characteristics (i.e., composition and structure of sleeping trees are needed to improve our understanding of the ecological significance of spider monkeys in influencing forest composition. Moreover, since primate populations are increasingly forced to inhabit fragmented landscapes, it is important to assess if these characteristics differ between continuous and fragmented forests. We assessed this novel information from eight independent spider monkey communities in the Lacandona rainforest, Mexico: four continuous forest sites and four forest fragments. Both the density of sleeping sites and latrines did not differ between forest conditions. Latrines were uniformly distributed across sleeping sites, but the spatial distribution of sleeping sites within the areas was highly variable, being particularly clumped in forest fragments. In fact, the average inter-latrine distances were almost double in continuous forest than in fragments. Latrines were located beneath only a few tree species, and these trees were larger in diameter in continuous than fragmented forests. Because latrines may represent hotspots of seedling recruitment, our results have important ecological and conservation implications. The variation in the spatial distribution of sleeping sites across the forest indicates that spider monkeys likely create a complex seed deposition pattern in space and time. However, the use of a very few tree species for sleeping could contribute to the establishment of specific vegetation associations

  18. Forest microbiome: diversity, complexity and dynamics

    Czech Academy of Sciences Publication Activity Database

    Baldrian, Petr

    2017-01-01

    Roč. 41, č. 2 (2017), s. 109-130 ISSN 0168-6445 R&D Projects: GA ČR GA13-06763S; GA ČR GA13-27454S; GA MŠk(CZ) LD15086 Institutional support: RVO:61388971 Keywords : forests * microbiome * habitat Subject RIV: EE - Microbiology, Virology Impact factor: 12.198, year: 2016

  19. Site Productivity and Forest Carbon Stocks in the United States: Analysis and Implications for Forest Offset Project Planning

    Directory of Open Access Journals (Sweden)

    James E. Smith

    2012-06-01

    Full Text Available The documented role of United States forests in sequestering carbon, the relatively low cost of forest-based mitigation, and the many co-benefits of increasing forest carbon stocks all contribute to the ongoing trend in the establishment of forest-based carbon offset projects. We present a broad analysis of forest inventory data using site quality indicators to provide guidance to managers planning land acquisition for forest-based greenhouse gas mitigation projects. Specifically, we summarize two condition class indicators of site productivity within the FIA forest inventory database—physclcd and siteclcd—as they relate to current aboveground live tree carbon stocks. Average carbon density is higher on more productive sites, but compared to the overall variability among sites, the differences are relatively small for all but the highest and lowest site classes. Some minor differences in eastern- versus western-forests were apparent in terms of how carbon on the least productive sites differed from most other forest land over time. Overall results suggest that xeric sites in most regions as well as sites that correspond to the lowest, non-productive classifications of forest land should preferentially not be used forestry-based greenhouse gas mitigation projects, but all other forest areas appear to be suitable.

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

    Science.gov (United States)

    Kwon, Y.

    2013-12-01

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

  1. Distribution of millipedes (Myriapoda, Diplopoda along a forest interior – forest edge – grassland habitat complex

    Directory of Open Access Journals (Sweden)

    Dávid Bogyó

    2015-06-01

    Full Text Available We studied the distribution of millipedes in a forest interior-forest edge-grassland habitat complex in the Hajdúság Landscape Protection Area (NE Hungary. The habitat types were as follows: (1 lowland oak forest, (2 forest edge with increased ground vegetation and shrub cover, and (3 mesophilous grassland. We collected millipedes by litter and soil sifting. There were overall 30 sifted litter and soil samples: 3 habitat types × 2 replicates × 5 soil and litter samples per habitats. We collected 9 millipede species; the most abundant species was Glomeris tetrasticha, which was the most abundant species in the forest edge as well. The most abundant species in the forest interior was Kryphioiulus occultus, while the most abundant species in the grassland was Megaphyllum unilineatum. Our result showed that the number of millipede species was significantly lower in the grassland than in the forest or in the edge, however there were no significant difference in the number of species between the forest interior and the forest edge. We found significantly the highest number of millipede individuals in the forest edge. There were differences in the composition of the millipede assemblages of the three habitats. The results of the DCCA showed that forest edge and forest interior habitats were clearly separated from the grassland habitats. The forest edge habitat was characterized by high air temperature, high soil moisture, high soil pH, high soil enzyme activity, high shrub cover and low canopy cover. The IndVal and the DCCA methods revealed the following character species of the forest edge habitats: Glomeris tetrasticha and Leptoiulus cibdellus. Changes in millipede abundance and composition were highly correlated with the vegetation structure.

  2. Distribution of millipedes (Myriapoda, Diplopoda) along a forest interior – forest edge – grassland habitat complex

    Science.gov (United States)

    Bogyó, Dávid; Magura, Tibor; Nagy, Dávid D.; Tóthmérész, Béla

    2015-01-01

    Abstract We studied the distribution of millipedes in a forest interior-forest edge-grassland habitat complex in the Hajdúság Landscape Protection Area (NE Hungary). The habitat types were as follows: (1) lowland oak forest, (2) forest edge with increased ground vegetation and shrub cover, and (3) mesophilous grassland. We collected millipedes by litter and soil sifting. There were overall 30 sifted litter and soil samples: 3 habitat types × 2 replicates × 5 soil and litter samples per habitats. We collected 9 millipede species; the most abundant species was Glomeris tetrasticha, which was the most abundant species in the forest edge as well. The most abundant species in the forest interior was Kryphioiulus occultus, while the most abundant species in the grassland was Megaphyllum unilineatum. Our result showed that the number of millipede species was significantly lower in the grassland than in the forest or in the edge, however there were no significant difference in the number of species between the forest interior and the forest edge. We found significantly the highest number of millipede individuals in the forest edge. There were differences in the composition of the millipede assemblages of the three habitats. The results of the DCCA showed that forest edge and forest interior habitats were clearly separated from the grassland habitats. The forest edge habitat was characterized by high air temperature, high soil moisture, high soil pH, high soil enzyme activity, high shrub cover and low canopy cover. The IndVal and the DCCA methods revealed the following character species of the forest edge habitats: Glomeris tetrasticha and Leptoiulus cibdellus. Changes in millipede abundance and composition were highly correlated with the vegetation structure. PMID:26257542

  3. Distribution of millipedes (Myriapoda, Diplopoda) along a forest interior - forest edge - grassland habitat complex.

    Science.gov (United States)

    Bogyó, Dávid; Magura, Tibor; Nagy, Dávid D; Tóthmérész, Béla

    2015-01-01

    We studied the distribution of millipedes in a forest interior-forest edge-grassland habitat complex in the Hajdúság Landscape Protection Area (NE Hungary). The habitat types were as follows: (1) lowland oak forest, (2) forest edge with increased ground vegetation and shrub cover, and (3) mesophilous grassland. We collected millipedes by litter and soil sifting. There were overall 30 sifted litter and soil samples: 3 habitat types × 2 replicates × 5 soil and litter samples per habitats. We collected 9 millipede species; the most abundant species was Glomeristetrasticha, which was the most abundant species in the forest edge as well. The most abundant species in the forest interior was Kryphioiulusoccultus, while the most abundant species in the grassland was Megaphyllumunilineatum. Our result showed that the number of millipede species was significantly lower in the grassland than in the forest or in the edge, however there were no significant difference in the number of species between the forest interior and the forest edge. We found significantly the highest number of millipede individuals in the forest edge. There were differences in the composition of the millipede assemblages of the three habitats. The results of the DCCA showed that forest edge and forest interior habitats were clearly separated from the grassland habitats. The forest edge habitat was characterized by high air temperature, high soil moisture, high soil pH, high soil enzyme activity, high shrub cover and low canopy cover. The IndVal and the DCCA methods revealed the following character species of the forest edge habitats: Glomeristetrasticha and Leptoiuluscibdellus. Changes in millipede abundance and composition were highly correlated with the vegetation structure.

  4. LBA-ECO CD-04 Dendrometry, km 83 Tower Site, Tapajos National Forest, Brazil

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: A dendrometry study was conducted at the logged forest tower site, km 83 site, Tapajos National Forest, Para, Brazil over a period of 4 years following the...

  5. Redox potential: An indicator of site productivity in forest management

    Science.gov (United States)

    Sajedi, Toktam; Prescott, Cindy; Lavkulich, Les

    2010-05-01

    Redox potential (Eh) is an integrated soil measurement that reflects several environmental conditions in the soil associated with aeration, moisture and carbon (organic matter) dynamics. Its measurement can be related to water table fluctuations, precipitation and landscape gradients, organic matter decomposition rates, nutrient dynamics, biological diversity and plant species distribution. Redox is an excellent indicator of soil biological processes, as it is largely a reflection of microbial activities which to a large extent govern carbon dynamics and nutrient cycling. Redox thus serves as an ecological indicator of site productivity at the ecosystem scale and may be used for management purposes as its magnitude can be altered by activities such as harvesting and drainage. A threshold value of 300 mv has been documented as the critical value below which anaerobic conditions in the soil develop. However, redox measurements and its impacts on ecosystem processes such as nutrient cycling and productivity, especially in forest ecosystems, have not received the attention that this "master" variable deserves, On northern Vancouver Island, Canada, regenerating stands of western redcedar-western hemlock (CH) sites exhibit symptoms of nutrient deficiencies and slow growth, but this phenomenon does not occur on adjacent western hemlock- amabalis fir (HA) sites. We tested the hypothesis that differences in nutrient supply and distribution of plant species was caused by differences in moisture regime and redox potential. Redox potential, pH, soil aeration depth (steel rods), organic matter thickness, bulk density, soil carbon store, plant species distribution and richness were measured at five old-growth and five 10-year-old cutover blocks. Results of investigations confirmed that CH forests were wetter, had redox values lower than the critical 300mv and a shallower aerated zone, compared with adjacent regenerating HA sites. Fifty percent of the CH plots had redox values

  6. Oak Forest Composition, Site Quality, and Dynamics in Relation to Site Factors in the Southeastern Missouri Ozarks

    Science.gov (United States)

    John M. Kabrick; Stephen R. Shifley; Randy G. Jensen; David R. Larsen; Jennifer K. Grabner

    2004-01-01

    Physical site factors are known to affect forest species composition but the pattern and variation across forest landscapes has not been well quantified. We discuss relationships between site factors including soil parent materials, depth to dolomite bedrock, aspect, and landform position and the distribution of vegetation, site index, and short-term succession in oak...

  7. Long-term monitoring sites and trends at the Marcell Experimental Forest. Chapter 2.

    Science.gov (United States)

    Stephen D. Sebestyen; Carrie Dorrance; Donna M. Olson; Elon S. Verry; Randall K. Kolka; Art E. Elling; Richard. Kyllander

    2011-01-01

    The MEF is one of few long-term research programs on the hydrology and ecology of undrained peatlands in boreal forests. No other site in the Experimental Forest and Range Network of the Forest Service and few sites around the globe have studied the hydrology and biogeochemistry of peatland watersheds with the intensity or longevity as on the MEF. In this chapter, we...

  8. A sequential iterative dual-filter for Lidar terrain modeling optimized for complex forested environments

    Science.gov (United States)

    Véga, C.; Durrieu, S.; Morel, J.; Allouis, T.

    2012-07-01

    This paper introduces a sequential iterative dual-filter method for filtering Lidar point clouds acquired over rough and forested terrain and computing a digital terrain model (DTM). The method belongs to the family of virtual deforestation algorithms that iteratively detect and filter objects above-the ground surface. The method uses both points and raster models to do so. The algorithm performance was first tested over a complex badlands environment and compared to a reference model obtained using a traditional TIN-Iterative approach. It was further tested on a benchmark site of the ISPRS (site 5) representing mainly forests and slopes. Over badlands, the resulting DTM elevation RMSE was 0.14 m over flat areas, and increased to 0.28 m under forested and rough terrain. The later value was 12.5% lower than the one obtained with a TIN-Iterative approach. Over the ISPRS site, the TIN-Iterative model provided better results for 3 out of the 4 sample sites. But the proposed algorithm, still worked fairly well provided a total classification error of 5.52%, and is well ranked compared with other algorithms. While the TIN-iterative approach might work better with low density, the proposed one is a good alternative to process high density point cloud and compute DTMs suitable for modeling either hydrodynamic or morphological processes under forest cover at a local scale.

  9. Forest type affects the influence of harvest on annual and cumulative litter decay in forest and wetland sites across Canada.

    Science.gov (United States)

    Trofymow, J. A.; Thompson, E.; Cameron, A.; Pare, D.; Lavigne, M.; Flanagan, L.; Moore, T.; Amiro, B.; Smyth, C.

    2007-12-01

    A litter decomposition study was established in 16 sites at 7 stations of the Fluxnet Canada Research Network. These sites included paired mature and clearcut forest sites at 5 upland stations (BC, SK, ON, QC, NB) as well as one site at each of two wetland stations (AW, QW) . All sites are instrumented for in situ measurements of soil moisture and temperature. Litterbags were prepared using one of four standard material types (aspen leaves - AL, black spruce needles BS, Douglas fir needles DF and birch wood sticks BW). Six replicate plots were located at each site, each plot contained sufficient numbers of surface litterbags of each material type to allow for four annual collections (2004 - 2007). As well unconfined birch chopsticks were placed at three depths down the soil profile (surface, 5cm, 15cm) and replaced annually to examine the effects of interannual variability on decay. Cumulative litter decay after three years litters rank by % mass remaining had ALforests, other than birchwood at one site (QC). Decay of surface birch sticks were similar and interannual variability was less than variability down the soil profile. The effects of clearcut varied with forest site type, on wetter sites surface BW decayed faster in clearcuts than closed forest, however this was reversed in drier forest site types. At lower soil depths on drier sites, decay was more rapid in clearcuts than closed forest. Work is continuing to relate insitu microclimates to decay rates.

  10. LBA-ECO CD-04 Leaf Area Index, km 83 Tower Site, Tapajos National Forest, Brazil

    Data.gov (United States)

    National Aeronautics and Space Administration — Leaf area index was estimated in an 18 ha plot at the logged forest tower site, km 83, Tapajos National Forest, Para, Brazil. The plot was adjacent to the eddy flux...

  11. Using LiDAR Metrics to Characterize Forest Structural Complexity at Multiple Scales

    Science.gov (United States)

    Kane, V. R.; McGaughey, R. J.; Gersonde, R.; Franklin, J. F.

    2007-12-01

    Forest structure - the size and arrangement of trees and foliage - reflects a stand's history of initiation, growth, disturbance, and mortality. Because of this, studying the structure of forests can provide key insights into ecological processes, guides to silvicultural prescriptions to improve habitat, and assessments of forested landscapes. This study tested LiDAR metrics to characterize stands based on canopy structure. The study site was the 34,591 ha of forests in the Cedar River Watershed in western Washington State, USA. Stands ranged in age from 350 years old (including old-growth). Study sites spanned the western hemlock- Douglas fir (Tsuga heterophylla-Pseudotsuga menziesii), Pacific silver fir (Abies amabilis), and mountain hemlock (Tsuga mertansiana) forest zones. Eighty sample plots were used to ground truth the LiDAR data. A variety of structural indices were used to study canopy structural variations at the plot, stand, and landscape scales. The two most successful indices used the exposed geometry of the canopy surface: (1) the ratio of the canopy surface area to ground surface area (rumple index), and (2) the ratio of the volume beneath the canopy surface to maximum volume beneath the 95th percentile height (modified canopy volume method). These two indices integrated the spatial effects of tree heights, foliage distribution, and tree arrangement within 15m pixels. Variation between pixels revealed structural complexity at larger scales. Results: At the plot scale (~4 pixels), correlations with standard plot metrics (e.g., diameter at breast height) were similar to those reported by other studies. Comparison of structural complexity with age and height revealed a diversity of development pathways. The relationship between height and complexity allowed stands to be classified by the degree to which they have achieved their potential structural complexity, a new way to examine forest development. At the stand scale, the indices allowed spatial

  12. Measurements of particulate sugars at urban and forested suburban sites

    Science.gov (United States)

    Tominaga, Sae; Matsumoto, Kiyoshi; Kaneyasu, Naoki; Shigihara, Ado; Katono, Koichi; Igawa, Manabu

    2011-04-01

    Neutral sugars (arabinose, fucose, galactose, glucose, mannose, rhamnose, and xylose) in fine and coarse aerosols were measured at urban and forested suburban sites in Japan. The most dominant compound in the sugar group was glucose at both sites. Size partitioning of the sugars generally showed dominance in the fine mode range but shifted toward the coarse mode range in summer. Seasonal trends in the sugar concentrations in the fine and coarse mode ranges were opposite: higher concentrations of fine mode sugars were found in winter, although coarse mode sugars increased in summer. Fine mode glucose consisted dominantly of the combined form, whereas free glucose increased in the coarse mode range. Although the sources of the sugars in the aerosols remain largely uncertain, primary biogenic particles can be considered as candidates of main sources of the sugars in both coarse and fine mode ranges.

  13. Complex mountain terrain and disturbance history drive variation in forest aboveground live carbon density in the western Oregon Cascades, USA.

    Science.gov (United States)

    Zald, Harold S J; Spies, Thomas A; Seidl, Rupert; Pabst, Robert J; Olsen, Keith A; Steel, E Ashley

    2016-04-15

    was also affected by finer scale topographic conditions associated with sheltered sites. Past wildfires only had a small influence on current ALC density, which may be a result of long times since fire and/or prevalence of non-stand replacing fire. Our results indicate that forest ALC density depends on a suite of multi-scale environmental drivers mediated by complex mountain topography, and that these relationships are dependent on stand age. The high and context-dependent spatial variability of forest ALC density has implications for quantifying forest carbon stores, establishing upper bounds of potential carbon sequestration, and scaling field data to landscape and regional scales.

  14. Transforming Pinus pinaster forest to recreation site: preliminary effects on LAI, some forest floor, and soil properties.

    Science.gov (United States)

    Öztürk, Melih; Bolat, İlyas

    2014-04-01

    This study investigates the effects of forest transformation into recreation site. A fragment of a Pinus pinaster plantation forest was transferred to a recreation site in the city of Bartın located close to the Black Sea coast of northwestern Turkey. During the transformation, some of the trees were selectively removed from the forest to generate more open spaces for the recreationists. As a result, Leaf Area Index (LAI) decreased by 0.20 (about 11%). Additionally, roads and pathways were introduced into the site together with some recreational equipment sealing parts of the soil surface. Consequently, forest environment was altered with a semi-natural landscape within the recreation site. The purpose of this study is to assess the effects of forest transformation into recreation site particularly in terms of the LAI parameter, forest floor, and soil properties. Preliminary monitoring results indicate that forest floor biomass is reduced by 26% in the recreation site compared to the control site. Soil temperature is increased by 15% in the recreation site where selective removal of trees expanded the gaps allowing more light transmission. On the other hand, the soil bulk density which is an indicator of soil compaction is unexpectedly slightly lower in the recreation site. Organic carbon (C(org)) and total nitrogen (N(total)) together with the other physical and chemical parameter values indicate that forest floor and soil have not been exposed to much disturbance. However, subsequent removal of trees that would threaten the vegetation, forest floor, and soil should not be allowed. The activities of the recreationists are to be concentrated on the paved spaces rather than soil surfaces. Furthermore, long-term monitoring and management is necessary for both the observation and conservation of the site.

  15. EVALUATING THE NOVEL METHODS ON SPECIES DISTRIBUTION MODELING IN COMPLEX FOREST

    Directory of Open Access Journals (Sweden)

    C. H. Tu

    2012-07-01

    Full Text Available The prediction of species distribution has become a focus in ecology. For predicting a result more effectively and accurately, some novel methods have been proposed recently, like support vector machine (SVM and maximum entropy (MAXENT. However, high complexity in the forest, like that in Taiwan, will make the modeling become even harder. In this study, we aim to explore which method is more applicable to species distribution modeling in the complex forest. Castanopsis carlesii (long-leaf chinkapin, LLC, growing widely in Taiwan, was chosen as the target species because its seeds are an important food source for animals. We overlaid the tree samples on the layers of altitude, slope, aspect, terrain position, and vegetation index derived from SOPT-5 images, and developed three models, MAXENT, SVM, and decision tree (DT, to predict the potential habitat of LLCs. We evaluated these models by two sets of independent samples in different site and the effect on the complexity of forest by changing the background sample size (BSZ. In the forest with low complex (small BSZ, the accuracies of SVM (kappa = 0.87 and DT (0.86 models were slightly higher than that of MAXENT (0.84. In the more complex situation (large BSZ, MAXENT kept high kappa value (0.85, whereas SVM (0.61 and DT (0.57 models dropped significantly due to limiting the habitat close to samples. Therefore, MAXENT model was more applicable to predict species’ potential habitat in the complex forest; whereas SVM and DT models would tend to underestimate the potential habitat of LLCs.

  16. Development and Verification of CFD Models for Modeling Wind Conditions on Forested Wind Turbine Sites

    DEFF Research Database (Denmark)

    Andersen, Morten Q.; Mortensen, Kasper; Nielsen, Daniel E.

    2009-01-01

    This paper describes a proposed CFD model to simulate the wind conditions on a forested site. The model introduces porous subdomains representing the forests in the terrain. Obtained simulation values are compared to field measurements in- and outside a forest. Initial results are very promising...

  17. Modeling forest site productivity using mapped geospatial attributes within a South Carolina landscape, USA

    Science.gov (United States)

    B.R. Parresol; D.A. Scott; S.J. Zarnoch; L.A. Edwards; J.I. Blake

    2017-01-01

    Spatially explicit mapping of forest productivity is important to assess many forest management alternatives. We assessed the relationship between mapped variables and site index of forests ranging from southern pine plantations to natural hardwoods on a 74,000-ha landscape in South Carolina, USA. Mapped features used in the analysis were soil association, land use...

  18. Reconstruction of forest site history in Ethiopian highlands based on {sup 13}C natural abundance of soils

    Energy Technology Data Exchange (ETDEWEB)

    Eshetu, Z.; Hoegberg, P. [Swedish Univ. of Agricultural Sciences, Umeaa (Sweden). Dept. of Forest Ecology

    2000-03-01

    Deforestation has been occurring in Ethiopia for millennia and has accelerated during the last century. On the other hand, historical accounts indicate that restricted afforestation of mountainous areas was initiated already 550 years ago. One of these areas was the Menagesha Forest. To reconstruct forest site history, soil samples from the Menagesha Forest and Wendo-Genet areas were analyzed for {sup 13}C natural abundance and C concentration. In soils from Menagesha, {delta}{sup 13}C values ranged from -17 per mille to -23 per mille in the deeper horizons, and from -24 per mille to -27 per mille in the surface mineral soils and litter layer. This indicates that C{sub 4} grasses were once an important component of this ecosystem, and supports the historical accounts. In the Wendo-Genet area, {delta}{sup 13}C values ranged from -16 per mille to -14 per mille in the deeper horizons, and from -23 per mille to -16 per mille in the topsoil in both cultivated lands and forested sites, suggesting more recent shifts from grassland to woodland or forest. With regard to reforestation and soil conservation, it is encouraging that productive forest with high soil organic carbon concentration could be established on the steep slopes at Menagesha. The study also shows that Ethiopian forest history is more complex than commonly appreciated, and that there has not been a simple unbroken trend of deforestation.

  19. Observed response of vulnerable forest ecosystems to ongoing site condition changes

    Science.gov (United States)

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

    2017-04-01

    In the last decades, several symptoms of drought damages have been observed in the Hungarian forests (e.g. sparse canopy, leaf drop, top drying, fungal diseases). Forest responses are also influenced by other factors beyond climate (e.g. available water content, soil conditions, biotic damages, adaptive capacity, etc.). Our aim was to prepare a complex analysis of the change of all site conditions, that could lead to the observed health status decline of the forest tree species. For a case study region in Hungary (Keszthely Mountains, near to Lake Balaton) precipitation and temperature tendencies as well as the frequency of extreme dry summers have been determined for the period 1961-2100. Soil conditions have been investigated in 9 profiles and soil mapping analysis has been carried out including 100 sites with hand soil auger. For the investigation of the water-balance we used the modified Thornthwaite-type monthly model and determined water stress when the relative extractable water (REW) decreased below 40% (Granier et al., 1999). In the last 30 years three severe droughts have been detected when duration of extremely dry and hot periods exceeded 3-4 years. Not only orographic and microclimate conditions but also soil types show a large diversity within a relatively small distance in the case study area. On rendzina with shallow topsoil layer thickness, low water holding capacity, black pine was planted. Brown earth with medium and brown forest soils with deep topsoil layer thickness is favourable for oak (sessile or Turkey) and beech. These microscale differences between the three site condition types resulted different available water contents quantified by the modified Thornthwaite-type monthly water-balance model. Our results show the different sensitivity of the studied sites to water stress. It means that the local scale orographic and soil conditions can enhance the projected drought risk of the region. However, the favourable microclimatic effects of

  20. LBA-ECO CD-10 Temperature Profiles at km 67 Tower Site, Tapajos National Forest

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains a single text file which reports temperature measurements at the Para Western (Santarem) - km 67, Primary Forest Tower Site. This site is in...

  1. Effects of organizational complexity and resources on construction site risk.

    Science.gov (United States)

    Forteza, Francisco J; Carretero-Gómez, Jose M; Sesé, Albert

    2017-09-01

    Our research is aimed at studying the relationship between risk level and organizational complexity and resources on constructions sites. Our general hypothesis is that site complexity increases risk, whereas more resources of the structure decrease risk. A Structural Equation Model (SEM) approach was adopted to validate our theoretical model. To develop our study, 957 building sites in Spain were visited and assessed in 2003-2009. All needed data were obtained using a specific tool developed by the authors to assess site risk, structure and resources (Construction Sites Risk Assessment Tool, or CONSRAT). This tool operationalizes the variables to fit our model, specifically, via a site risk index (SRI) and 10 organizational variables. Our random sample is composed largely of small building sites with general high levels of risk, moderate complexity, and low resources on site. The model obtained adequate fit, and results showed empirical evidence that the factors of complexity and resources can be considered predictors of site risk level. Consequently, these results can help companies, managers of construction and regulators to identify which organizational aspects should be improved to prevent risks on sites and consequently accidents. Copyright © 2017 National Safety Council and Elsevier Ltd. All rights reserved.

  2. Assessing the Sensitivity of Mountain Forests to Site Degradation in the Northern Limestone Alps, Europe

    Directory of Open Access Journals (Sweden)

    Birgit Reger

    2015-05-01

    Full Text Available Because of some land-use practices (such as overstocking with wild ungulates, historical clear-cuts for mining, and locally persisting forest pasture, protective forests in the montane vegetation belt of the Northern Limestone Alps are now frequently overaged and poorly structured over large areas. Windthrow and bark beetle infestations have generated disturbance areas in which forests have lost their protective functions. Where unfavorable site conditions hamper regeneration for decades, severe soil loss may ensue. To help prioritize management interventions, we developed a geographic information system-based model for assessing sensitivity to site degradation and applied it to 4 test areas in the Northern Limestone Alps of Austria and Bavaria. The model consists of (1 analysis of site conditions and forest stand structures that could increase sensitivity to degradation, (2 evaluation of the sensitivity of sites and stands, and (3 evaluation and mapping of mountain forests' sensitivity to degradation. Site conditions were modeled using regression algorithms with data on site parameters from pointwise soil and vegetation surveys as responses and areawide geodata on climate, relief, and substrate as predictors. The resulting predictor–response relationships were applied to test areas. Stand structure was detected from airborne laser scanning data. Site and stand parameters were evaluated according to their sensitivity to site degradation. Sensitivities of sites and stands were summarized in intermediate-scale sensitivity maps. High sensitivity was identified in 3 test areas with pure limestone and dolomite as the prevailing sensitivity level. Moderately sensitive forests dominate in the final test area, Grünstein, where the bedrock in some strata contains larger amounts of siliceous components (marl, mudstone, and moraines; degraded and slightly sensitive forests were rare or nonexistent in all 4 test areas. Providing a comprehensive overview

  3. Comprehensive characterization of atmospheric organic carbon at a forested site

    Science.gov (United States)

    Hunter, James F.; Day, Douglas A.; Palm, Brett B.; Yatavelli, Reddy L. N.; Chan, Arthur W. H.; Kaser, Lisa; Cappellin, Luca; Hayes, Patrick L.; Cross, Eben S.; Carrasquillo, Anthony J.; Campuzano-Jost, Pedro; Stark, Harald; Zhao, Yunliang; Hohaus, Thorsten; Smith, James N.; Hansel, Armin; Karl, Thomas; Goldstein, Allen H.; Guenther, Alex; Worsnop, Douglas R.; Thornton, Joel A.; Heald, Colette L.; Jimenez, Jose L.; Kroll, Jesse H.

    2017-10-01

    Atmospheric organic compounds are central to key chemical processes that influence air quality, ecological health, and climate. However, longstanding difficulties in predicting important quantities such as organic aerosol formation and oxidant lifetimes indicate that our understanding of atmospheric organic chemistry is fundamentally incomplete, probably due in part to the presence of organic species that are unmeasured using standard analytical techniques. Here we present measurements of a wide range of atmospheric organic compounds--including previously unmeasured species--taken concurrently at a single site (a ponderosa pine forest during summertime) by five state-of-the-art mass spectrometric instruments. The combined data set provides a comprehensive characterization of atmospheric organic carbon, covering a wide range in chemical properties (volatility, oxidation state, and molecular size), and exhibiting no obvious measurement gaps. This enables the first construction of a measurement-based local organic budget, highlighting the high emission, deposition, and oxidation fluxes in this environment. Moreover, previously unmeasured species, including semivolatile and intermediate-volatility organic species (S/IVOCs), account for one-third of the total organic carbon, and (within error) provide closure on both OH reactivity and potential secondary organic aerosol formation.

  4. LBA-ECO CD-03 Cloud Base-Backscatter Data, km 67 Tower Site, Tapajos National Forest

    Data.gov (United States)

    National Aeronautics and Space Administration — A Vaisala CT-25K ceilometer was installed at an old-growth forest site located at the km 67 Eddy Flux Tower site in the Tapajos National Forest, Para, Brazil, off...

  5. Surveying marbled murrelets at inland forested sites: a guide

    Science.gov (United States)

    Peter W.C. Paton; C. John Ralph; Harry R. Carter; S. Kim Nelson

    1990-01-01

    The marbled murrelet (Brachyramphus marmoratus), a seabird, nests in forested stands from southeast Alaska south to Santa Cruz, California. Because of this species' close association with old-growth forests, researchers and land managers need a method to assess murrelet distribution and use patterns throughout its range. This guide describes a...

  6. NPP Multi-Biome: Grassland, Boreal Forest, and Tropical Forest Sites, 1939-1996, R1

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains one data file (.csv format) that provides net primary productivity (NPP) estimates for 34 grasslands, 14 tropical forests, and 5 boreal forest...

  7. LBA-ECO CD-10 Forest Litter Data for km 67 Tower Site, Tapajos National Forest

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains a single text file which reports litter type and mass in the old-growth upland forest at the Para Western (Santarem) - km 67, Primary Forest...

  8. Vertical structure of evapotranspiration at a spruce forest site

    Science.gov (United States)

    Staudt, K.; Falge, E.; Serafimovich, A.; Pyles, D.; Foken, T.

    2009-12-01

    The Advanced Canopy-Atmosphere-Soil Algorithm (ACASA) was used to model the turbulent fluxes of heat, water vapor and momentum as well as the carbon dioxide exchange within and above a spruce canopy at the FLUXNET-station Waldstein-Weidenbrunnen (DE-Bay) in the Fichtelgebirge mountains in northern Bavaria, Germany. ACASA is a multilayer canopy-surface-layer model that incorporates a third-order closure method to calculate turbulent transfer within and above the canopy and was developed at the University of California, Davis. Within the EGER (ExchanGE processes in mountainous Regions) project, comprehensive micrometeorological and plant physiological measurements were performed during two intensive observation periods in fall 2007 and summer 2008. This data base allowed us to extensively test the ability of the ACASA model to simulate the exchange of energy and matter at our site. Here, the vertical structure of evapotranspiration within and above the canopy for a few days is investigated in detail. The ACASA model provides profiles of all components of evapotranspiration, such as transpiration and evaporation from the soil, and estimates the interception of precipitation and the corresponding evaporation from wet plant surfaces. Fluxes of momentum, heat, carbon dioxide and water vapor were measured with six eddy-covariance systems below, within and above the canopy on a 36 m high tower. Furthermore, xylem sapflow measurements at six heights within the canopy were performed for the determination of canopy transpiration. This combination of multilevel measurements allowed us to estimate all components of evapotranspiration of and within the spruce forest. Model results and measurements of evapotranspiration are analyzed with regard to the partitioning between its components as well as between the canopy layers. Furthermore, the ability of the ACASA model to reproduce evapotranspiration profiles for different exchange regimes of the subcanopy and the canopy is

  9. [Recovery of three tropical forest covers from mid-elevation sites in Costa Rica: oligochaetes, litter and soil analysis].

    Science.gov (United States)

    Pérez-Molina, Junior Pastor; Cordero Solórzano, Roberto A

    2012-12-01

    addition, comparing soil nutrients content (organic carbon, nitrogen, calcium, potassium and sulfur) among the three sites, our findings indicate that the cypress plantation had reached soil nutrient conditions similar to the old secondary forest, presumably by the accumulation of nutrients, as a result of low nutrient recirculation. In conclusion, ecosystem level studies throughout simple evaluation criteria (soils, oligochaetes and ground litter) can be used as rapid indicators of the state of some of the many and complex forest ecosystem compartments.

  10. Evidence that soil aluminum enforces site fidelity of southern New England forest trees

    Science.gov (United States)

    S. W. Bigelow; C. D. Canham

    2010-01-01

    Tree species composition of hardwood forests of the northeastern United States corresponds with soil chemistry, and differential performance along soil calcium (Ca) gradients has been proposed as a mechanism for enforcing this fidelity of species to site. We conducted studies in a southern New England forest to test if surface-soil Ca is more important than other...

  11. Expanding site productivity research to sustain non-timber forest functions

    Science.gov (United States)

    D. Andrew Scott; James A. Burger; Barbara Crane

    2006-01-01

    Southern forests produce multiple products and services including timber, wildlife habitat, species bio- and genetic divenity, water quality and control, waste remediation, recreation, and carbon sequestration. All of these benefits must be produced in a sustainable manner to meet today's societal needs without compromising future needs. A forest site is...

  12. NPP Tropical Forest: Consistent Worldwide Site Estimates, 1967-1999

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: Currently available data on net primary production in tropical forests are extremely limited. Even the best estimates for this biome must be thought of as...

  13. Occurrence and formation of chloroform at Danish forest sites

    DEFF Research Database (Denmark)

    Haselmann, K.F.; Ketola, R.A.; Laturnus, F.

    2000-01-01

    Ambient air and soil air of spruce forest, beech forest and grassland from Zealand, Denmark, were investigated for volatile chlorinated compounds by adsorbent tube sampling, thermodesorption, cryo-trapping and analysis by high-resolution gas chromatography with electron capture detection. The mean...... the initial soil air concentration after 38 h, while the concentrations of the other volatile chlorinated compounds investigated remained fairly constant. The observed chloroform concentration profiles and release rates may indicate a biogenic formation of chloroform in the upper soil layer of spruce forests......, whereas an anthropogenic origin is suggested for the other chlorinated compounds investigated. From the release study and concentration gradient measurements in the spruce forest soil, chloroform release to the atmosphere was calculated for northern temperate regions. The release was in the range...

  14. Influence of headwater site conditions and riparian buffers on terrestrial salamander response to forest thinning.

    Science.gov (United States)

    D.E. Rundio; D.H. Olson

    2007-01-01

    We examined the effect of forest thinning and riparian buffers along headwater streams on terrestrial salamanders at two sites in western Oregon. Salamander numbers were reduced postthinning at one site with lower down-wood volume. Terrestrial salamander distributions along stream-to-upslope transects suggest benefits of one and two site-potential tree-height stream...

  15. Remediation management of complex sites using an adaptive site management approach.

    Science.gov (United States)

    Price, John; Spreng, Carl; Hawley, Elisabeth L; Deeb, Rula

    2017-12-15

    Complex sites require a disproportionate amount of resources for environmental remediation and long timeframes to achieve remediation objectives, due to their complex geologic conditions, hydrogeologic conditions, geochemical conditions, contaminant-related conditions, large scale of contamination, and/or non-technical challenges. A recent team of state and federal environmental regulators, federal agency representatives, industry experts, community stakeholders, and academia worked together as an Interstate Technology & Regulatory Council (ITRC) team to compile resources and create new guidance on the remediation management of complex sites. This article summarizes the ITRC team's recommended process for addressing complex sites through an adaptive site management approach. The team provided guidance for site managers and other stakeholders to evaluate site complexities and determine site remediation potential, i.e., whether an adaptive site management approach is warranted. Adaptive site management was described as a comprehensive, flexible approach to iteratively evaluate and adjust the remedial strategy in response to remedy performance. Key aspects of adaptive site management were described, including tools for revising and updating the conceptual site model (CSM), the importance of setting interim objectives to define short-term milestones on the journey to achieving site objectives, establishing a performance model and metrics to evaluate progress towards meeting interim objectives, and comparing actual with predicted progress during scheduled periodic evaluations, and establishing decision criteria for when and how to adapt/modify/revise the remedial strategy in response to remedy performance. Key findings will be published in an ITRC Technical and Regulatory guidance document in 2017 and free training webinars will be conducted. More information is available at www.itrc-web.org. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. LBA-ECO CD-04 Meteorological and Flux Data, km 83 Tower Site, Tapajos National Forest

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: Tower flux measurements of carbon dioxide,water vapor, heat, and meteorological variables were obtained at the Tapajos National Forest, km 83 site,...

  17. LBA-ECO CD-04 Meteorological and Flux Data, km 83 Tower Site, Tapajos National Forest

    Data.gov (United States)

    National Aeronautics and Space Administration — Tower flux measurements of carbon dioxide,water vapor, heat, and meteorological variables were obtained at the Tapajos National Forest, km 83 site, Santarem, Para,...

  18. LBA-ECO CD-04 LAI Estimated from Photos, km 83 Tower Site, Tapajos National Forest

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set contains summary data for monthly leaf area index (LAI) and plant area index (PAI) at the km 83 Tower Site, in the Tapajos National Forest,...

  19. LBA-ECO CD-04 LAI Estimated from Photos, km 83 Tower Site, Tapajos National Forest

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains summary data for monthly leaf area index (LAI) and plant area index (PAI) at the km 83 Tower Site, in the Tapajos National Forest, Para,...

  20. LBA-ECO CD-04 Soil Respiration, km 83 Tower Site, Tapajos National Forest, Brazil

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set reports on the flux of carbon dioxide from logged forest soils near the eddy flux tower at the km 83 site, Para, Brazil. The automated soil...

  1. LBA-ECO CD-10 Temperature Profiles at km 67 Tower Site, Tapajos National Forest

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set contains a single text file which reports temperature measurements at the Para Western (Santarem) - km 67, Primary Forest Tower Site. This...

  2. CMS: LiDAR-derived Estimates of Aboveground Biomass at Four Forested Sites, USA

    Data.gov (United States)

    National Aeronautics and Space Administration — These data consist of high-resolution maps of aboveground biomass at four forested sites in the US: Garcia River Tract in California, Anne Arundel and Howard...

  3. CMS: LiDAR-derived Estimates of Aboveground Biomass at Four Forested Sites, USA

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: These data consist of high-resolution maps of aboveground biomass at four forested sites in the US: Garcia River Tract in California, Anne Arundel and...

  4. CMS: LiDAR Data for Forested Sites on Borneo Island, Kalimantan, Indonesia, 2014

    Data.gov (United States)

    National Aeronautics and Space Administration — This dataset provides airborne LiDAR data collected over 90 sites totaling approximately 100,000 hectares of forested land in Kalimantan, Indonesia on the island of...

  5. LBA-ECO CD-04 CO2 Profiles, km 83 Tower Site, Tapajos National Forest

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: Atmospheric carbon dioxide profiles were measured at 12 levels up to 64 m at the km 83 logged tower site in Tapajos National Forest, Santarem, Para,...

  6. LBA-ECO CD-04 Biomass Survey, km 83 Tower Site, Tapajos National Forest, Brazil

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set contains the results of a biometric tree survey of a 19.25 ha area adjacent to the eddy flux tower at the km 83 logged forest tower site in...

  7. LBA-ECO CD-04 Biomass Survey, km 83 Tower Site, Tapajos National Forest, Brazil

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains the results of a biometric tree survey of a 19.25 ha area adjacent to the eddy flux tower at the km 83 logged forest tower site in Tapajos...

  8. Waste of Felling and On-Site Production of Teak Squarewood of the Community Forest

    Directory of Open Access Journals (Sweden)

    Ahmad Budiaman

    2012-12-01

    Full Text Available Major suppliers of teak wood for the raw material of furniture industry in Indonesia are Perum Perhutani, community forests, and private forests.  Community teak forest management produce roundwood or squarewood, in which squarewood is produced on the felling site by the use of chainsaw after felling and bucking activities. Utilization of teak wood from community forest has been practiced for decades, however information on the extent of utilization and the quantity of wood waste have not been published to a greater extent. The present research was intended to determine and analyze the extent of utilization and teak wood waste produced from felling and bucking, and on-site squarewood production of community forests.  Quantification of wood waste from felling and bucking was based on the whole tree method, while that of squarewood production was based on the percentage of yield. It was found that the quantity of teak felling and bucking wood waste in community forest was reaching 28% of felled wood volume that consisted of branch and twig (46.15%, upper trunk (30.77%, short cut off (15.38%, and stumps (7.69%. The largest part of the wood waste of teak felling and bucking satisfied the requirement as raw material of wood working industry according to Indonesian National Standard. On-site production of squarewood increased the quantity of wood waste in the forests (in the form of slabs and sawdust.Keywords: wood waste, felling, bucking, squarewood, community forest

  9. Short-term responses of the small mammal communities to forest management within Missouri Ozark Forest Ecosystem Project sites

    Science.gov (United States)

    Debby K. Frantz; Rochelle B. Renken

    2002-01-01

    We conducted a capture-recapture study on the northeast-facing slopes of the MOFEP sites in south central Missouri to determine the initial effects of even- and uneven-aged forest management on species composition, species richness, and relative abundance of the small mammal communities. We compared changes between pre-treatment (1994-1995) and post-treatment (1998-...

  10. More than trees, do we need a complex perspective for sustainable forest management?

    CERN Document Server

    López-Corona, Oliver; Pérez-Cirera, Vanessa; de León-González, Fernando; Dirzo, Rodolfo

    2016-01-01

    Forests are complex systems, and it is necessary to include this characteristic in every forest definition, in order to consider the restriction that this imposes in terms of prediction and control. This lost of predictability and controllability should be incorporated in every Environmental Impact Assessment or management program. We present two case-studies located in Mexico and one in the US to illustrate three relevant indicators of complexity. First, we introduce an informational framework to measure the Zoquiapan forest systemic complexity. Then, we analyze complexity changes among different types of forest and management systems, related with spatial distributions, using data from a floristic study in the Montes Azules National Park. Finally, we analyze time series of $CO_{2}$ fluctuations taken from AMERIFLUX data bases. Our results show firstly that it is possible to measure the systemic complexity of different forests, characteized by a criticality state (1/f noise) which has been proposed as a fing...

  11. When the shifting agriculture is gone: functionality of Atlantic Coastal Forest in abandoned farming sites

    Directory of Open Access Journals (Sweden)

    Rogério Ribeiro de Oliveira

    2008-08-01

    Full Text Available Slash-and-burn agriculture has been practiced for a very long time by the traditional populations (caiçaras on Ilha Grande, Rio de Janeiro State, Brazil. After a few years of use the plots are abandoned to fallow. We examined the processes of litter production and decomposition and the relationships between forest lands used by caiçara populations and landscape functionality. Five and 25-year-old forests growing on areas once used for subsistence agriculture were compared to a near-climax forest site. No significant differences between the three areas were noted in terms of litter production over a 2-yr period; the average litter productions were 9,927, 8,707 and 10,031 kg/ha/yr for the 5-year, 25-year and climax forests respectively. N and K nutrient input through litter was greatest in the climax forest; P and Mg input was greatest in the 5-yr forest; and Na greatest in the 25-yr forest. Ground litter accumulation (3,040-3,730 kg/ha/yr was not significantly different in the three areas. Litter turnover times (1/K were 0.33, 0.42 and 0.38 for the 5-yr, 25-yr and climax forests respectively. These secondary forests cover almost all of Ilha Grande and demonstrate low species diversity, but they have production and decomposition systems similar to those of mature forests.

  12. Mycorrhizal associations in Ailanthus altissima (Simaroubaceae) from forested and non-forested sites

    Science.gov (United States)

    Cynthia D. Huebner; Carolyn McQuattie; Joanne Rebbeck

    2007-01-01

    Ailanthus altissima tree seedlings were excavated from each of two habitats: (1) a forest adjacent to a trail and stream and (2) a non-forested steep, barren slope adjacent to a major highway. Each seedling root system was examined for colonization by mycorrhizal structures using light microscopy and transmission electron microscopy. The roots were...

  13. Productivity of forests of the United States and its relation to soil and site factors and management practices: a review.

    Science.gov (United States)

    C.C. Grier; K.M. Lee; N.M. [and others]. Nadkarni

    1989-01-01

    Data on net primary biological productivity of United States forests are summarized by geographic region. Site factors influencing productivity are reviewed. This paper is a review of existing literature in the productivity of various forest regions of the United States, the influence of site factors on forest productivity, and the impact of various...

  14. Numerical Simulations of the Microscale Heterogeneities of Turbulence Observed on a Complex Site

    Science.gov (United States)

    Zaïdi, Hanane; Dupont, Eric; Milliez, Maya; Musson-Genon, Luc; Carissimo, Bertrand

    2013-05-01

    We simulate the microscale heterogeneities of turbulent variables observed at a complex site for different wind directions. The atmospheric computational fluid dynamics (CFD) results are compared with an ensemble of 36 months of data collected at the experimental site SIRTA "Site Instrumental de Recherche par Télédétection Atmosphérique", located near Paris (France) in a semi-urban environment. The experimental data show that the normalized turbulent kinetic energy (TKE) k/ U 2 (where k is TKE and U is the wind speed) at 10-m height, for two different locations, is highly dependent on wind direction and strongly influenced by trees. These measurements show a strong increase of the normalized TKE downstream of the forest canopies with a large variability within the 36-month period in part due to the variation of the tree foliage. The numerical simulations are carried out using the CFD code Code_Saturne with the standard k-ɛ closure, in neutral stratification. The buildings are taken into account explicitly in the mesh and the forested areas are modelled with two approaches: the classical roughness wall law and a drag porosity. A comparison has been performed between the calculated values and the median of measured values of the normalized TKE and the normalized friction velocity, for each wind sector of 10°. A very good agreement is obtained with the drag porosity model, whereas the classical roughness law leads to a strong underestimation downstream of the forested areas. However, this large improvement of the results using the drag porosity model can only be obtained with a refinement of the grid, especially in forested areas, and an accurate land-use map.

  15. Deposition of nitrogen oxides and ozone to Danish forest sites

    DEFF Research Database (Denmark)

    Pilegaard, K.; Jensen, N.O.; Hummelshøj, P.

    1995-01-01

    of the influence of meteorological factors. The viscous sub-layer resistance is derived by a new theory, taking the bluff roughness elements of the forest and the dimension of the needles/leaves as well as the LAI into account. The fluxes of nitrogen dioxide and ozone are related to the fluxes of water vapour...

  16. Cosmic-ray neutron transport at a forest field site

    DEFF Research Database (Denmark)

    Andreasen, Mie; Jensen, Karsten Høgh; Desilets, Darin

    2017-01-01

    -ray neutron intensity is essential (e.g., the effect of vegetation, litter layer and soil type). In this study the environmental effect is examined by performing a sensitivity analysis using neutron transport modeling. We use a neutron transport model with various representations of the forest and different...

  17. Characterization of aerosol particles at the forested site in Lithuania

    Science.gov (United States)

    Rimselyte, I.; Garbaras, A.; Kvietkus, K.; Remeikis, V.

    2009-04-01

    Atmospheric particulate matter (PM), especially fine particles (particles with aerodynamic diameter less than 1 m, PM1), has been found to play an important role in global climate change, air quality, and human health. The continuous study of aerosol parameters is therefore imperative for better understanding the environmental effects of the atmospheric particles, as well as their sources, formation and transformation processes. The particle size distribution is particularly important, since this physical parameter determines the mass and number density, lifetime and atmospheric transport, or optical scattering behavior of the particles in the atmosphere (Jaenicke, 1998). Over the years several efforts have been made to improve the knowledge about the chemical composition of atmospheric particles as a function of size (Samara and Voutsa, 2005) and to characterize the relative contribution of different components to the fine particulate matter. It is well established that organic materials constitute a highly variable fraction of the atmospheric aerosol. This fraction is predominantly found in the fine size mode in concentrations ranging from 10 to 70% of the total dry fine particle mass (Middlebrook et al., 1998). Although organic compounds are major components of the fine particles, the composition, formation mechanism of organic aerosols are not well understood. This is because particulate organic matter is part of a complex atmospheric system with hundreds of different compounds, both natural and anthropogenic, covering a wide range of chemical properties. The aim of this study was to characterize the forest PM1, and investigate effects of air mass transport on the aerosol size distribution and chemical composition, estimate and provide insights into the sources and characteristics of carbonaceous aerosols through analysis ^13C/12C isotopic ratio as a function of the aerosol particles size. The measurements were performed at the Rugšteliškis integrated

  18. Charcoal kiln sites, associated landscape attributes and historic forest conditions: DTM-based investigations in Hesse (Germany

    Directory of Open Access Journals (Sweden)

    Marcus Schmidt

    2016-03-01

    Full Text Available Background An examination of the distribution of ancient charcoal kiln sites in the forest landscape seems to be worthwhile, since general trends in the selection of suitable kiln site locations in the past might become obvious. In this way forest landscape elements with a more intense usage by charcoal burning can be identified. By doing this, we can expect to gain information on the former condition and tree species composition of woodland. Investigations on the spatial distribution of charcoal kiln sites in relation to landscape attributes are sparse, however, probably due to the high on-site mapping effort. The outstanding suitability of LiDAR-derived digital terrain models (DTMs for the detection of charcoal kiln sites has been recently proved. Hence, DTM-based surveys of charcoal kiln sites represent a promising attempt to fill this research gap. Methods Based on DTM-based surveys, we analyzed the spatial distribution of charcoal kiln sites in two forest landscapes in the German federal state of Hesse: Reinhardswald and Kellerwald-Edersee National Park. In doing so, we considered the landscape attibutes "tree species composition", “water supply status”, “nutrient supply status”, “soil complex classes”, “altitude”, “exposition”, and “inclination”. Results We found that charcoal kiln sites were established preferably on hillside locations that provided optimal growing and regeneration conditions for European beech (Fagus sylvatica due to their acidic brown soils and sufficient water supply. These results are in line with instructions for the selection of appropriate kiln site locations, found in literature from the 18th to the 19th century. Conclusions We conclude that there were well-stocked, beech-dominated deciduous forest stands in northern Hesse before 1800, particularly at poorly accessible hillside locations. These large stocks of beech wood were utilized by the governments of the different Hessian territories

  19. LBA-ECO CD-10 Coarse Woody Debris Data at km 67 Tower Site, Tapajos National Forest

    Data.gov (United States)

    National Aeronautics and Space Administration — This data sets reports properties of fallen course woody debris in an old-growth upland forest at the Para Western (Santarem) - km 67, Primary Forest Tower Site....

  20. Quality of stump wood harvesting and forest regeneration on stump harvesting sites

    Energy Technology Data Exchange (ETDEWEB)

    Roenkkoe, R.; Ulander, E.; Sauvula-Seppaelae, T. (Seinaejoki Univ. of Applied Sciences, Aehtaeri (Finland), School of Agriculture and Forestry), e-mail: essi.ulander@seamk.fi, e-mail: tiina.sauvula-seppala@seamk.fi

    2010-07-01

    Stump harvesting for renewable energy production has recently become more common in Finland. Stump extraction intensifies forest management and alters the conditions for forest regeneration on stump harvesting sites. Here, the quality of stump wood harvesting, together with the quality of forest regeneration was studied on stump harvesting sites. The overall quality of stump harvesting was in accordance with the recommendations for energy wood harvesting. However, a significant difference in the area of disturbed soil was observed when the stumped sites were compared to non-stumped sites. On average, 48 % of the soil surface on the stumped sites was disturbed. The quality of site preparation was lower on the stumped than on the non-stumped sites. The amount of mounds was about 50 % of the recommended planting density for spruce on the stumped sites, and the amount of mounds was significantly lower than on the non-stumped sites. The possible effects of the changes in the soil conditions and the changes in the quality of site preparation need to be researched in relation to future site productivity. Where the current levels of knowledge are limited, precautionary measures need to be followed to prevent the potentially negative effects of stump harvesting. (orig.)

  1. Site disturbances associated with alternative prescriptions in an upland hardwood forest of northern Alabama

    Science.gov (United States)

    Emily Carter; Robert B. Rummer; Bryce Stokes

    1997-01-01

    A study was installed in an upland hardwood forest to evaluate the site impacts associated with three alternative prescriptions --- clearcut, deferment cut, and strip cut. Two methods of site impact assessment were employed: 1) assignment of disturbance classes to selected points within each treatment area; and 2) measurement of soil bulk density, gravimetric water...

  2. Forest site preparation effects on Georgia Piedmont soils over a 10-year period

    Science.gov (United States)

    James H. Miller; M.B. Edwards

    1997-01-01

    More than a quarter-million acres of forest lands in the Southeast are site prepared annually using mechanical treatments with little to no information on long-term soil sustainability outcomes. The objectives of this rcscarch was to gain a first-view of the soil changes after the following integrated site preparation (SP) treatments: none (cheek), chainsaw felling,...

  3. Forest site classification for cultural plant harvest by tribal weavers can inform management

    Science.gov (United States)

    S. Hummel; F.K. Lake

    2015-01-01

    Do qualitative classifications of ecological conditions for harvesting culturally important forest plants correspond to quantitative differences among sites? To address this question, we blended scientific methods (SEK) and traditional ecological knowledge (TEK) to identify conditions on sites considered good, marginal, or poor for harvesting the leaves of a plant (...

  4. Summer droughts limit tree growth across 10 temperate species on a productive forest site

    NARCIS (Netherlands)

    Weemstra, M.; Eilmann, B.; Sass-Klaassen, U.; Sterck, F.J.

    2013-01-01

    Studies on climate impacts on tree annual growth are mainly restricted to marginal sites. To date, the climate effects on annual growth of trees in favorable environments remain therefore unclear despite the importance of these sites in terms of forest productivity. Because species respond

  5. Distinct site specificity of two pea histone deacetylase complexes.

    Science.gov (United States)

    Clemente, S; Franco, L; López-Rodas, G

    2001-09-04

    We report on the site specificity of two intact pea histone deacetylase complexes. HD1 deacetylates lysines 5 and 16 of H4 in the order K16 > K5, while in the case of H3 the preferred order is K4 > K18 approximately K9. The specificity of the HD2 complex is markedly different. The preferred residues in H4 are K8 approximately K5 > K16, while in H3 deacetylation, the complex HD2 prefers sites 4 and 18. To obtain these results, we have used a novel procedure based on the SPOT technique, a method to synthesize peptides on membrane supports. Different sets of membranes with sequentially overlapping histone peptides containing acetylated lysines in the sites corresponding to all in vivo acetylatable residues were incubated with the complexes. The acetyl groups removed by the deacetylase activity were then replaced by radioactive acetate by treating the membranes with labeled acetic anhydride. The subsequent counting of the membranes allows the quantification of the acetate removal in the histone deacetylase reaction in a way that circumvents some of the inconveniences of other available procedures.

  6. NPP Multi-Biome: Grassland, Boreal Forest, and Tropical Forest Sites, 1939-1996, R1

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set contains one data file (.csv format) that provides net primary productivity (NPP) estimates for 34 grasslands, 14 tropical forests, and 5...

  7. LBA-ECO CD-10 Forest Litter Data for km 67 Tower Site, Tapajos National Forest

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set contains a single text file which reports litter type and mass in the old-growth upland forest at the Para Western (Santarem) - km 67,...

  8. Quantitative Analysis of Complex Tropical Forest Stands: A Review ...

    African Journals Online (AJOL)

    FIRST LADY

    Akindele (2008) showed that forestry research is based on scientific method which is popularly known to be the inductive-deductive approach. Consequently, foresters across the globe have become increasingly quantitative in their approaches to research and management; and with rising forest values; there is concomitant ...

  9. Forest Clearcutting and Site Preparation on a Saline Soil in East Texas: Impacts on Water Quality

    Science.gov (United States)

    Matthew McBroom; Mingteh Chang; Alexander K. Sayok

    2002-01-01

    Three 0.02 hectare plot-watersheds were installed on a saline soil in the Davy Crockett National Forest near Apple Springs, Texas. Each plot was installed with an H-flume, FW-1 automatic water level recorder, Coshocton N-1 runoff sampler, and two storage tanks. One watershed was undisturbed forested and served a control, one was clearcut without any site-preparation,...

  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. Predicting daily use of urban forest recreation sites

    Science.gov (United States)

    John F. Dwyer

    1988-01-01

    A multiple linear regression model explains 90% of the variance in daily use of an urban recreation site. Explanatory variables include season, day of the week, and weather. The results offer guides for recreation site planning and management as well as suggestions for improving the model.

  12. Binding site distribution of nuclear transport receptors and transport complexes in single nuclear pore complexes.

    Science.gov (United States)

    Kahms, Martin; Lehrich, Philipp; Hüve, Jana; Sanetra, Nils; Peters, Reiner

    2009-09-01

    Transport through the nuclear pore complex (NPC) involves a large channel and an abundance of binding sites for nuclear transport receptors (NTRs). However, the mechanistically important distribution of NTR-binding sites along the channel is vividly debated. In this study, we visualized binding site distributions directly by two complementary optical super-resolution methods, single-molecule microscopy and 4Pi microscopy. First, we analyzed the distribution of RanGDP because this important nuclear transport substrate has two types of binding sites at the NPC, direct and indirect, NTR-mediated sites. We found that the direct binding sites had a maximum at approximately -30 nm with regard to the NPC center, whereas the indirect transport-relevant binding sites peaked at approximately -10 nm. The 20 nm-shift could be only resolved by 4Pi microscopy because of a two to threefold improved localization precision as compared with single-molecule microscopy. Then we analyzed the distribution of the NTR Kapbeta1 and a Kapbeta1-based transport complex and found them to have also binding maxima at approximately -10 nm. These observations support transport models in which NTR binding sites are distributed all along the transport channel and argue against models in which the cytoplasmic entrance of the channel is surrounded by a large cloud of binding sites.

  13. Evaluating leaf litter beetle data sampled by Winkler extraction from Atlantic forest sites in southern Brazil

    Directory of Open Access Journals (Sweden)

    Philipp Werner Hopp

    2011-06-01

    Full Text Available Evaluating leaf litter beetle data sampled by Winkler extraction from Atlantic forest sites in southern Brazil. To evaluate the reliability of data obtained by Winkler extraction in Atlantic forest sites in southern Brazil, we studied litter beetle assemblages in secondary forests (5 to 55 years after abandonment and old-growth forests at two seasonally different points in time. For all regeneration stages, species density and abundance were lower in April compared to August; but, assemblage composition of the corresponding forest stages was similar in both months. We suggest that sampling of small litter inhabiting beetles at different points in time using the Winkler technique reveals identical ecological patterns, which are more likely to be influenced by sample incompleteness than by differences in their assemblage composition. A strong relationship between litter quantity and beetle occurrences indicates the importance of this variable for the temporal species density pattern. Additionally, the sampled beetle material was compared with beetle data obtained with pitfall traps in one old-growth forest. Over 60% of the focal species captured with pitfall traps were also sampled by Winkler extraction in different forest stages. Few beetles with a body size too large to be sampled by Winkler extraction were only sampled with pitfall traps. This indicates that the local litter beetle fauna is dominated by small species. Hence, being aware of the exclusion of large beetles and beetle species occurring during the wet season, the Winkler method reveals a reliable picture of the local leaf litter beetle community.

  14. Regional issues and wind energy project siting : Carolinian zone and forested habitats

    Energy Technology Data Exchange (ETDEWEB)

    Stephenson, D. [Natural Resource Solutions Inc., Waterloo, ON (Canada)

    2008-07-01

    This presentation considered regional siting considerations in Canada's Carolinian zone. The Carolinian zone is a biophysical region located in southern Canada. The region has received considerable interest from the wind power industry, and nearly 28 wind power projects have been planned in the region. The region is dominated by agricultural activities with fragmented natural habitats. Setbacks are a key consideration for wind farms constructed in the region. Hedgerows have an increased ecological importance in the region due to their ability to connect fragmented habitats. There are a high number of agricultural drains in the region. Wildlife patterns are directly related to changing cropping practices in the region. Meadow habitats are rapidly established in abandoned fields. The region is close to cottage developments in the Great Lakes. Daily movements between agricultural fields and shorelines must also be considered in wildlife movement assessments. Bird flight patterns in the region are diffuse with large seasonal and species variability. The clearing of forested areas may result in the direct loss of habitats and species. Site-specific inventories must be conducted at the environmental assessment (EA) stage. It was concluded that proposed wind farms in the region must be considered on a case-by-case basis due to the complexity of wildlife factors in the region. Bird mortality results from a wind farm in the region were also presented. tabs., figs.

  15. Assessment of national biomass in complex forests and technical capacity scenarios

    Science.gov (United States)

    Matieu Henry; Javier G. P. Gamarra; Gael Sola; Luca Birigazzi; Emily Donegan; Julian Murillo; Tommaso Chiti; Nicolas Picard; Miguel Cifuentes-Jara; S Sandeep; Laurent. Saint-André

    2015-01-01

    Understanding forest ecosystems is paramount for their sustainable management and for the livelihoods and ecosystem services which depend on them. However, the complexity and diversity of these systems poses a challenge to interpreting data patterns. The availability and accessibility of data and tools often determine the method selected for forest assessment. Capacity...

  16. Simulating restoration strategies for a southern boreal forest landscape with complex land ownership patterns

    Science.gov (United States)

    Douglas J. Shinneman; Meredith W. Cornett; Brian J. Palik

    2010-01-01

    Restoring altered forest landscapes toward their ranges of natural variability (RNV) may enhance ecosystem sustainability and resiliency, but such efforts can be hampered by complex land ownership and management patterns. We evaluated restoration potential for southern-boreal forests in the ~2.1 million ha Border Lakes Region of northern Minnesota (U.S.A.) and...

  17. Global warming and stress complexes in forests of western North America

    Science.gov (United States)

    Donald McKenzie; David L. Peterson; Jeremy J. Littell

    2009-01-01

    A warmer climate in western North America will likely affect forests directly through soil moisture stress and indirectly through increased extent and severity of disturbances. We propose that stress complexes, combinations of biotic and abiotic stresses, compromise the vigor and ultimate sustainability of forest ecosystems. Across...

  18. Challenges in forest reclamation of marginal lands: a balance between site conditions and seedling quality

    Science.gov (United States)

    Landhäusser, Simon

    2017-04-01

    Forest loss and degradation is occurring worldwide, but at the same time efforts in forest restoration are ever increasing. While approaches to restoration often follow specific stakeholder objectives, regional climates and the degree of site degradation also play an important role in the prioritization of restoration efforts. Often the restoration of degraded lands can satisfy only few measurable objectives; however, to design and restore resistant and resilient ecosystems that can adapt to changing conditions, there is a need for new and adaptive management approaches. Mining and other resource extraction industries are affecting more and more forested areas worldwide. A priority in the reclamation and certification of forest lands disturbed by industrial activity is their expeditious redevelopment to functioning forests. To rehabilitate these heavily disturbed areas back to forest ecosystems, planting of trees remains one of the most effective strategies for the redevelopment of a continuous tree canopy on a site. It is well understood that access to good quality seedling stock is essential to achieve establishment success and early growth of seedlings. However, most reclamation areas have challenging initial site conditions and these conditions are often not a single factor but a combination of factors that can be additive or synergistic. Therefore successful forest restoration on degraded lands needs to consider multiple objectives and approaches to minimize trade-offs in achieving these objectives. To meet these demands, new methods for the production and evaluation of seedling stock types are needed to ensure that that seedlings are fit to grow on a wide range of site conditions or are particularly designed to grow in very specific conditions. Generally, defining seedling quality is difficult as it is species specific and results have been mixed; likely influenced by site conditions, further reiterating the need to carefully evaluate sites allowing

  19. 76 FR 18713 - Malheur National Forest; Oregon; Malheur National Forest Site-Specific Invasive Plants Treatment...

    Science.gov (United States)

    2011-04-05

    ... other resource values such as scenic beauty and recreational opportunities. Invasive plants can spread... prevention standards in the R6 2005 ROD). The Malheur National Forest has been treating invasive plants... Service 2005b). Vectors and causes of invasive plant spread were explored in detail and new standards for...

  20. Building a "cyber forest" in complex terrain at the Andrews Experimental Forest

    Science.gov (United States)

    Donald L. Henshaw; Fred Bierlmaier; Barbara J. Bond; Kari B. O' Connell

    2008-01-01

    Our vision for a future "cyber forest" at the Andrews Experimental Forest foresees high performance wireless communications enhancing connectivity among remote field research locations, station headquarters, and beyond to the university and outside world. New sensor technologies and collaboration tools foretell exponential increases in data and information...

  1. Preliminary Evaluation of Methods for Classifying Forest Site Productivity Based on Species Composition in Western North Carolina

    Science.gov (United States)

    W. Henry McNab; F. Thomas Lloyd; David L. Loftis

    2002-01-01

    The species indicator approach to forest site classification was evaluated for 210 relatively undisturbed plots established by the USDA Forest Service Forest Inventory and Analysis uni (FIA) in western North Carolina. Plots were classified by low, medium, and high levels of productivity based on 10-year individual tree basal area increment data standardized for initial...

  2. The quinone-binding and catalytic site of complex II.

    Science.gov (United States)

    Maklashina, Elena; Cecchini, Gary

    2010-12-01

    The complex II family of proteins includes succinate:quinone oxidoreductase (SQR) and quinol:fumarate oxidoreductase (QFR). In the facultative bacterium Escherichia coli both are expressed as part of the aerobic (SQR) and anaerobic (QFR) respiratory chains. SQR from E. coli is homologous to mitochondrial complex II and has proven to be an excellent model system for structure/function studies of the enzyme. Both SQR and QFR from E. coli are tetrameric membrane-bound enzymes that couple succinate/fumarate interconversion with quinone/quinol reduction/oxidation. Both enzymes are capable of binding either ubiquinone or menaquinone, however, they have adopted different quinone binding sites where catalytic reactions with quinones occur. A comparison of the structures of the quinone binding sites in SQR and QFR reveals how the enzymes have adapted in order to accommodate both benzo- and napthoquinones. A combination of structural, computational, and kinetic studies of members of the complex II family of enzymes has revealed that the catalytic quinone adopts different positions in the quinone-binding pocket. These data suggest that movement of the quinone within the quinone-binding pocket is essential for catalysis. Published by Elsevier B.V.

  3. Mapping site index and volume increment from forest inventory, Landsat, and ecological variables in Tahoe National Forest, California, USA

    Science.gov (United States)

    Huang, Shengli; Ramirez, Carlos; Conway, Scott; Kennedy, Kama; Kohler, Tanya; Liu, Jinxun

    2016-01-01

    High-resolution site index (SI) and mean annual increment (MAI) maps are desired for local forest management. We integrated field inventory, Landsat, and ecological variables to produce 30 m SI and MAI maps for the Tahoe National Forest (TNF) where different tree species coexist. We converted species-specific SI using adjustment factors. Then, the SI map was produced by (i) intensifying plots to expand the training sets to more climatic, topographic, soil, and forest reflective classes, (ii) using results from a stepwise regression to enable a weighted imputation that minimized the effects of outlier plots within classes, and (iii) local interpolation and strata median filling to assign values to pixels without direct imputations. The SI (reference age is 50 years) map had an R2 of 0.7637, a root-mean-square error (RMSE) of 3.60, and a mean absolute error (MAE) of 3.07 m. The MAI map was similarly produced with an R2 of 0.6882, an RMSE of 1.73, and a MAE of 1.20 m3·ha−1·year−1. Spatial patterns and trends of SI and MAI were analyzed to be related to elevation, aspect, slope, soil productivity, and forest type. The 30 m SI and MAI maps can be used to support decisions on fire, plantation, biodiversity, and carbon.

  4. Influence of Microclimate on Semi-Arid Montane Conifer Forest Sapflux Velocity in Complex Terrain

    Science.gov (United States)

    Thirouin, K. R.; Barnard, D. M.; Barnard, H. R.

    2016-12-01

    Microclimate variation in complex terrain is key to our understanding of large-scale climate change effects on montane ecosystems. Modern climate models forecast that semi-arid montane ecosystems in the western United States are to experience increases in temperature, number of extreme drought events, and decreases in annual snowpack, all of which will potentially influence ecosystem water, carbon, and energy balances. In this study, we developed response curves that describe the relationships between stem sapflux velocity, air temperature (Tair), incoming solar radiation (SWin), soil temperature (Tsoil), and soil moisture content (VWC) in sites of Pinus contorta and Pinus ponderosa distributed along an elevation and aspect gradient in the montane zone of the Central Rocky Mountains, Colorado, USA. Among sites we found sapflux velocity to be significantly correlated with all four environmental factors (p < 0.05), but most strongly with SWin and Tair. The response of sapflux velocity to SWin was logarithmic, whereas the response to Tair indicated a peak sapflux velocity at a site-specific temperature that declined with increasing Tair. Sapflux velocity also increased with increasing VWC, but decreased with increasing Tsoil. At south-facing sites, the initial increase in the logarithmic response curve for SWin leveled off at 150-250 W m-2, whereas for north-facing sites it leveled off at 50-125 W m-2. While the differences in the SWin response between aspects could be due to species physiological differences, the highest elevation south-facing P. contorta site behaved similarly to the south-facing P. ponderosa, suggesting that environmental drivers may dominate the response. In response to Tair, peak sapflux velocity occurred at 12-13 degrees C at all sites except the mid-slope north-facing P. contorta site, which also had the lowest Tsoil. The responses of stem sapflux velocity to climate drivers indicate that forest transpiration is regulated by microclimate

  5. ASSESSING PASSIVE RESTORATION OF AN ATLANTIC FOREST SITE FOLLOWING A Cupressus lusitanica MILL. PLANTATION CLEARCUTTING

    Directory of Open Access Journals (Sweden)

    Roque Cielo-Filho

    2016-01-01

    Full Text Available Cupressus lusitanica has a relatively low potential for fostering colonization of native species beneath the forest canopy. However, following the clearcut of a Cupressus lusitanica plantation in the State Forest of Avaré (SFA, southeastern Brazil, a vigorous regeneration of Atlantic forest tree and shrub species was observed. We evaluated the passive restoration of this site by comparing its regenerating vegetation to the vegetation established in man-made gaps in Atlantic forest in the State Park of Cantareira (SPC, southeastern Brazil. The frequency distribution of dispersal syndromes for species and the rate of reduction in abundance of pioneer species in a rank/abundance plot did not differ between the two areas. The rarefaction curves for species richness and diversity of the SPC fall below the corresponding curves of the SFA. The proportions of non-pioneer species and of individuals of non-pioneer species were greater in the SFA. The frequency distribution of dispersal syndromes for individuals differed between the two areas due mainly to a more conspicuous predominance of zoochory in the SFA. The rate of reduction in abundance of non-pioneer species in a rank/abundance plot was smaller in the SFA. We concluded that passive restoration may successfully recover native vegetation attributes following the clearcut of forest plantations without conspicuous regeneration of native species beneath the forest canopy. However, this phenomenon may be influenced by particular properties of the forest species, logging practices and faunal seed dispersal integrity.

  6. Soil microbial diversity, site conditions, shelter forest land, saline water drip-irrigation, drift desert.

    Science.gov (United States)

    Jin, Zhengzhong; Lei, Jiaqiang; Li, Shengyu; Xu, Xinwen

    2013-10-01

    Soil microbes in forest land are crucial to soil development in extreme areas. In this study, methods of conventional culture, PLFA and PCR-DGGE were utilized to analyze soil microbial quantity, fatty acids and microbial DNA segments of soils subjected to different site conditions in the Tarim Desert Highway forest land. The main results were as follows: the soil microbial amount, diversity indexes of fatty acid and DNA segment differed significantly among sites with different conditions (F soil microbial community (>84%), followed by actinomycetes and then fungi (soil microbial diversity were insignificant at 0-35 cm. Correlation analysis indicated that the forest trees grew better as the soil microbial diversity index increased. Therefore, construction of the Tarim Desert Highway shelter-forest promoted soil biological development; however, for enhancing sand control efficiency and promoting sand development, we should consider the effects of site condition in the construction and regeneration of shelter-forest ecological projects. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Micro-scale modelling of energy fluxes over a small Fluxnet forest site in Denmark

    DEFF Research Database (Denmark)

    Sogachev, Andrey; Dellwik, Ebba; Boegh, Eva

    2012-01-01

    qualitative agreement with high-resolution (60 m and 120 m) remote-sensing data of the effective surface temperature of the area near the site in focus: the forested areas are colder in daytime and warmer in night time than surrounding open areas. In contrast to the remote sensing approach, SCADIS provides......Most forests, especially in Europe, are too small to fulfil strict fetch requirements associated with idealized flux observations in undisturbed, homogeneous flow. As a consequence of limited fetch, the flux measured above the canopy will often deviate from the source strength underlying...... model; Sogachev et al., 2002, Tellus 54B, 784-819) has been successfully applied especially in the region adjacent to a forest edge in order to improve flux data interpretation. Most of the analyses were done for the neutral case and in two-dimensional mode. When analyzing the effect of a forest edge...

  8. Environmental review for Site A/Plot M, Palos Forest Preserve, Cook County, Illinois

    Energy Technology Data Exchange (ETDEWEB)

    Biang, R.P.; Yuen, C.R.; Avci, H.I.; Haffenden, R.

    1993-06-01

    This report is an environmental review of two sites known as Site A and Plot M, which are located in the Palos Forest Preserve of the Forest Preserve District of Cook County, approximately 20 mi southwest of downtown Chicago and about 3 mi east of the current site of Argonne National Laboratory (ANL). An enlarged map of the area around the sites is shown in a figure. Site A covers about 19 acres, and Plot M covers about 1 acre. This document consists of the following sections: a review of the site history and environment, a description of the conceptual pathway models for both Site A and Plot M and a brief discussion of previous sampling events, a discussion of possible transport pathways, an evaluation of the Phase 2 Work Plan for Site A, a review of the applicable or relevant and appropriate regulations (ARARs), and recommendations for future study. The recommendations are based on an evaluation of previously collected data. Where data were sufficient, a geologic conceptual model was developed. If data were not sufficient to develop a model, recommendations for data collection are made. A new base map was developed for the site by using the base survey conducted in the 1940s, aerial photographs dating back to 1948, and site visits.

  9. Site quality influence over understory plant diversity in old-growth and harvested Nothofagus pumilio forests

    Energy Technology Data Exchange (ETDEWEB)

    Gallo, E. A.; Lencinas, M. V.; Martinez-Pastur, G. J.

    2013-05-01

    Aim of study: The effects and interactions of shelter wood forest harvesting and site qualities over understory plant species diversity and composition were compared among primary and harvested Nothofagus pumilio forests. Area of study: Tierra del Fuego (Argentina), on three pure conditions (one and six year-old harvested, and primary without previous harvesting forests) and three site qualities (high, medium and low). Material and Methods: Understory richness and cover (%) were registered in five replicates of 1 hectare each per treatment. Taxonomic species were classified in categories (groups, origin and life forms). Two-way ANOVAs and multivariate analyses were conducted. Main results: Shelterwood harvesting and site quality significantly influenced understory cover and richness, which allow the introduction of native and exotic species and increasing of dicot and monocot covers. In dicots, monocots, exotics and total groups, higher richness and covers were related to time. Meanwhile, cover reached similar high values in all site qualities on dicot, native and total groups. On the other hand, monocot and exotic richness and cover remain similar in primary and recently harvested forests, and greatly increased in old harvested forests. Mosses and ferns were among the most sensitive groups. Research highlights: Impacts of shelterwood cut depend on site quality of the stands and time since harvesting occurs. For this, different site quality stands should received differential attention in the development of conservation strategies, as well as variations in the shelterwood implementation (as irregularity and patchiness) should be considered to better promote understory plant species conservation inside managed areas. (Author) 45 refs.

  10. IUFRO Symposium on forest site and continuous productivity: Seattle, Washington, August 22-28, 1982.

    Science.gov (United States)

    Russell Ballard; Stanley P. Gessel

    1983-01-01

    This Symposium was planned by members of the IUFRO Site Group (S1.02) as part of their on-going activities to facilitate the worldwide exchange of ideas among individual research workers and to promote the dissemination of research results in the area of forest site productivity. The Symposium consisted of three days of indoor sessions followed by a 2-1/2-day field...

  11. Biogeochemical cycling of carbon, nitrogen, and sulfur at the Howland Integrated Forest Study site, Howland, Maine

    Science.gov (United States)

    James W. McLaughlin; Ivan J. Fernandez; Stewart M. Goltz; Lindsey E. Rustad; Larry Zibilske

    1996-01-01

    The biogeochemistry of C, N, and S was studied for six years at the Howland Integrated Forest Study (HIFS) site by measuring those constituents in major above- and below-ground pools and fluxes. Leaching losses of C from the solum were much less than CO2 efflux, with a mean annual leaching rate of 31.2 kg ha-1 yr

  12. Longleaf pine site response to repeated fertilization and forest floor removal by raking and prescribed burning

    Science.gov (United States)

    Kim Ludovici; Robert Eaton; Stanley Zarnoch

    2018-01-01

    Removal of forest floor litter by pine needle raking and prescribed burning is a common practice in longleaf pine (Pinus palustris Mill.) stands on Coastal Plain sites in the Southeastern United States. Repeated removal of litter by raking and the loss of surface organic matter from controlled burns can affect the...

  13. VOLATILE ORGANIC COMPOUNDS AND ISOPRENE OXIDATION PRODUCTS AT A TEMPERATE DECIDUOUS FOREST SITE

    Science.gov (United States)

    Biogenic volatile compounds (BVOCs) and their role in atmospheric oxidant formation were investigated at a forest site near Oak Ridge, Tennessee, as part of the Nashville Southern Oxidants Study (SOS) in July 1995. Of 98 VOCs detected, a major fraction were anthropogenic VOCs suc...

  14. Foliar and soil chemistry at red spruce sites in the Monongahela National Forest

    Science.gov (United States)

    Stephanie J. Connolly

    2010-01-01

    In 2005, soil and foliar chemistry were sampled from 10 sites in the Monongahela National Forest which support red spruce. Soils were sampled from hand-dug pits, by horizon, from the O-horizon to bedrock or 152 cm, and each pit was described fully. Replicate, archived samples also were collected.

  15. The interactive impact of forest site and stand attributes and logging technology on stand management

    Science.gov (United States)

    C.B. LeDoux; J.E. Baumgras

    1991-01-01

    The impact of selected site and stand attributes on stand management is demonstrated using actual forest model plot data and a complete systems simulation model called MANAGE. The influence of terrain on the type of logging technology required to log a stand and the resulting impact on stand management is also illustrated. The results can be used by managers and...

  16. Temporal Trends of Ecosystem Development on Different Site Types in Reclaimed Boreal Forests

    Directory of Open Access Journals (Sweden)

    Bradley D. Pinno

    2015-06-01

    Full Text Available Forest development after land reclamation in the oil sands mining region of northern Alberta, Canada was assessed using long-term monitoring plots from both reclaimed and natural forests. The metrics of ecosystem development analyzed included measures of plant community structure and composition and soil nutrient availability. Early seral reclamation plots were grouped by site type (dry and moist-rich and age categories, and these were compared with mature natural forests. There were few significant differences in ecosystem metrics between reclamation site types, but natural stands showed numerous significant differences between site types. Over time, there were significant changes in most plant community metrics such as species richness and cover of plant community groups (e.g., forbs, shrubs, and non-native species, but these were still substantially different from mature forests 20 years after reclamation. Available soil nitrogen did not change over time or by reclamation site type but available soil phosphorus did, suggesting that phosphorus may be a more suitable indicator of ecosystem development. The significant temporal changes in these reclaimed ecosystems indicate that studies of ecosystem establishment and development on reclaimed areas should be conducted over the long-term, emphasizing the utility of monitoring using long-term plot networks.

  17. Snags and Down Wood on Upland Oak Sites in the Missouri Ozark Forest Ecosystem Project

    Science.gov (United States)

    Stephen R. Shifley; Brian L. Brookshire; David R. Larsen; Laura A. Herbeck; Randy G. Jensen

    1997-01-01

    We analyzed volume, surface area, and percent cover of down wood to determine if there were pre-treatment differences among the sites in the Missouri Ozark Forest Ecosystem Project. We also compared pre-treatment values for the number and basal area of snags. We observed no statistically significant differences (P > 0.05) among treatment classes for these...

  18. Forest Soil Productivity on the Southern Long-Term Soil Productivity Sites at Age 5

    Science.gov (United States)

    D. Andrew Scott; Allan E. Tiarks; Felipe G. Sanchez; Michael Elliott-Smith; Rick Stagg

    2004-01-01

    Forest management operations have the potential to reduce soil productivity through organic matter and nutrient removal and soil compaction. We measured pine volume, bulk density, and soil and foliar nitrogen and phosphorus at age 5 on the 13 southern Long-Term Soil Productivity study sites. The treatments were organic matter removal [bole only (BO), whole tree (WT),...

  19. Use Trends Indicated by Statistically Calibrated Recreational Sites in the National Forest System

    Science.gov (United States)

    Gary L. Tyre

    1971-01-01

    Trends in statistically sampled use of developed sites in the National Forest system indicate an average annual increase of 6.0 percent in the period 1966-69. The high variability of the measure precludes its use for projecting expected future use, but it can be important in gauging the credibility of annual use changes at both sampled and unsampled locations.

  20. Modeling wildfire regimes in forest landscapes: abstracting a complex reality

    Science.gov (United States)

    Donald McKenzie; Ajith H. Perera

    2015-01-01

    Fire is a natural disturbance that is nearly ubiquitous in terrestrial ecosystems. The capacity to burn exists virtually wherever vegetation grows. In some forested landscapes, fi re is a principal driver of rapid ecosystem change, resetting succession ( McKenzie et al. 1996a ) and changing wildlife habitat (Cushman et al. 2011 ), hydrology ( Feikema et al. 2013 ),...

  1. Foliar nutrients in Italian forests: results from the 1995-2009 monitoring network sites CONECOFOR

    Directory of Open Access Journals (Sweden)

    De Cinti B

    2013-11-01

    Full Text Available Foliar nutrients in Italian forests: results from the 1995-2009 monitoring network sites CONECOFOR. In 1995, the Italian Forest Service (CFS established the National Network for Forest Ecosystem Monitoring (CONECOFOR with the aim to study the ecological interactions among structural and functional components of forest stands. In the 31 permanent plots of the CONECOFOR Network, surveys are carried out including vegetation, trees crown condition, chemistry of leaves and soils, tree growth, atmospheric deposition, climate, microclimate, ozone and biodiversity. These surveys are carried out by CFS in collaboration with several scientific institutions. In such context, IBAF/CNR is specifically involved in the investigation of foliage chemical content. The foliar nutritional status was analyzed in 25 sites, taking as a reference the values published by the ICP-Forests and those published in the literature. The study involved 7 forest species (Quercus cerris, Q. petraea, Q. robur, Q. ilex, Fagus sylvatica, Carpinus betulus and Picea abies investigating the concentrations of the major macronutrients as nitrogen (N, phosphorus (P, potassium (K, magnesium (Mg, sulfur (S and calcium (Ca and the N/P ratio. In beech, N, S and K were found in quite high concentrations, though without showing imbalances due to concentration excesses. Ca and Mg are present in very high concentrations, highlighting the possibility of imbalances, especially in relation to the other nutrients. For these two nutrients, spruce shows substantially balanced conditions as also for N/P ratio. For deciduous Oaks nutrients arewithin the parameters of normality, with the exception of Ca. This has been observed in 4 out of the 6 studied sites, with potential indication of nutritional imbalances related to Calcium. Nutrient concentrations in Holm oak are within the average of published data, except for Ca and Mg of site TOS-1, the former being slightly low, the latter being unusually high

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-06-29

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

  3. The complexities of managing forest resources in post-decentralization Indonesia: a case study from Sintang District, West Kalimantan

    NARCIS (Netherlands)

    Yasmi, Y.; Anshari, Gusti Z.; Alqadrie, S.; Budiarto, T.; Ngusmanto,; Abidin, E.; Komarudin, H.; McGrath, S.; Zulkifli,; Afifudin,

    2005-01-01

    The study attempted to understand the dynamics and complexities of forest resources management following decentralization, the interactions among stakeholders in forest resources management, and the impacts of the new legislation on local community livelihoods in Sintang District, West Kalimantan.

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

    Directory of Open Access Journals (Sweden)

    Vilanee Suchewaboripont

    2017-01-01

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

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

    Science.gov (United States)

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

    2016-04-01

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

  6. On the complexity of measuring forests microclimate and interpreting its relevance in habitat ecology: the example of Ixodes ricinus ticks.

    Science.gov (United States)

    Boehnke, Denise; Gebhardt, Reiner; Petney, Trevor; Norra, Stefan

    2017-11-06

    Ecological field research on the influence of meteorological parameters on a forest inhabiting species is confronted with the complex relations between measured data and the real conditions the species is exposed to. This study highlights this complexity for the example of Ixodes ricinus. This species lives mainly in forest habitats near the ground, but field research on impacts of meteorological conditions on population dynamics is often based on data from nearby official weather stations or occasional in situ measurements. In addition, studies use very different data approaches to analyze comparable research questions. This study is an extensive examination of the methodology used to analyze the impact of meteorological parameters on Ixodes ricinus and proposes a methodological approach that tackles the underlying complexity. Our specifically developed measurement concept was implemented at 25 forest study sites across Baden-Württemberg, Germany. Meteorological weather stations recorded data in situ and continuously between summer 2012 and autumn 2015, including relative humidity measures in the litter layer and different heights above it (50 cm, 2 m). Hourly averages of relative humidity were calculated and compared with data from the nearest official weather station. Data measured directly in the forest can differ dramatically from conditions recorded at official weather stations. In general, data indicate a remarkable relative humidity decrease from inside to outside the forest and from ground to atmosphere. Relative humidity measured in the litter layer were, on average, 24% higher than the official data and were much more balanced, especially in summer. The results illustrate the need for, and benefit of, continuous in situ measurements to grasp the complex relative humidity conditions in forests. Data from official weather stations do not accurately represent actual humidity conditions in forest stands and the explanatory power of short period and

  7. On the complexity of measuring forests microclimate and interpreting its relevance in habitat ecology: the example of Ixodes ricinus ticks

    Directory of Open Access Journals (Sweden)

    Denise Boehnke

    2017-11-01

    Full Text Available Abstract Background Ecological field research on the influence of meteorological parameters on a forest inhabiting species is confronted with the complex relations between measured data and the real conditions the species is exposed to. This study highlights this complexity for the example of Ixodes ricinus. This species lives mainly in forest habitats near the ground, but field research on impacts of meteorological conditions on population dynamics is often based on data from nearby official weather stations or occasional in situ measurements. In addition, studies use very different data approaches to analyze comparable research questions. This study is an extensive examination of the methodology used to analyze the impact of meteorological parameters on Ixodes ricinus and proposes a methodological approach that tackles the underlying complexity. Methods Our specifically developed measurement concept was implemented at 25 forest study sites across Baden-Württemberg, Germany. Meteorological weather stations recorded data in situ and continuously between summer 2012 and autumn 2015, including relative humidity measures in the litter layer and different heights above it (50 cm, 2 m. Hourly averages of relative humidity were calculated and compared with data from the nearest official weather station. Results Data measured directly in the forest can differ dramatically from conditions recorded at official weather stations. In general, data indicate a remarkable relative humidity decrease from inside to outside the forest and from ground to atmosphere. Relative humidity measured in the litter layer were, on average, 24% higher than the official data and were much more balanced, especially in summer. Conclusions The results illustrate the need for, and benefit of, continuous in situ measurements to grasp the complex relative humidity conditions in forests. Data from official weather stations do not accurately represent actual humidity conditions in

  8. Classification and evaluation for forest sites on the Natchez Trace State Forest, State Resort Park, and Wildlife Management Area in West Tennessee

    Science.gov (United States)

    Glendon W. Smalley

    1991-01-01

    Presents comprehensive forest site classification system for the 45,084-acre Natchez Trace State Forest, State Resort park, and WIldlife Management Area in the highly dissected and predominantly hilly Upper Coastal Plain of west Tennessee. Twenty-five landtypes are identified. Each landtype is defined in terms of nine elements and evaluated on the baiss of...

  9. Complex response of the forest nitrogen cycle to climate change

    OpenAIRE

    Bernal, Susana; Hedin, L. O.; Likens, G. E.; Gerber, S; Buso, D.

    2012-01-01

    Climate exerts a powerful influence on biological processes, but the effects of climate change on ecosystem nutrient flux and cycling are poorly resolved. Although rare, long-term records offer a unique opportunity to disentangle effects of climate from other anthropogenic influences. Here, we examine the longest and most complete record of watershed nutrient and climate dynamics available worldwide, which was collected at the Hubbard Brook Experimental Forest in the northeastern United State...

  10. Seed Bank Variation under Contrasting Site Quality Conditions in Mixed Oak Forests of Southeastern Ohio, USA

    Directory of Open Access Journals (Sweden)

    Christine J. Small

    2010-01-01

    Full Text Available Seed bank composition was sampled in 192–2.5 m2 quadrats, established in six regenerating clearcut (∼7 years and six second-growth (∼125 years mixed-oak forest stands in southeastern Ohio. Seed bank and aboveground composition diverged markedly (Sørensen's coefficient <10%, emphasizing the importance of fast-growing, early-successional germinants to early ecosystem recovery. Seed richness was significantly (P<.01 higher in clearcut stands, suggesting declining richness with stand age. Richness estimations 28%–60% higher than observed values demonstrated high seed bank heterogeneity, emphasizing the need for intensive sampling to assess temperate forest seed bank variation. Site quality (topographic aspect strongly influenced seed bank composition, with greater importance of early-successional trees, thicket-forming shrubs, and nonnative species on mesic sites. Thus, forest seed banks are likely to play an important, site-dependent role in shaping competitive environments for commercially important timber species after harvesting and soil disturbance and have the potential for marked influence on postharvest forest development.

  11. Seeing the Forest through the Trees: Considering Roost-Site Selection at Multiple Spatial Scales.

    Science.gov (United States)

    Jachowski, David S; Rota, Christopher T; Dobony, Christopher A; Ford, W Mark; Edwards, John W

    2016-01-01

    Conservation of bat species is one of the most daunting wildlife conservation challenges in North America, requiring detailed knowledge about their ecology to guide conservation efforts. Outside of the hibernating season, bats in temperate forest environments spend their diurnal time in day-roosts. In addition to simple shelter, summer roost availability is as critical as maternity sites and maintaining social group contact. To date, a major focus of bat conservation has concentrated on conserving individual roost sites, with comparatively less focus on the role that broader habitat conditions contribute towards roost-site selection. We evaluated roost-site selection by a northern population of federally-endangered Indiana bats (Myotis sodalis) at Fort Drum Military Installation in New York, USA at three different spatial scales: landscape, forest stand, and individual tree level. During 2007-2011, we radiotracked 33 Indiana bats (10 males, 23 females) and located 348 roosting events in 116 unique roost trees. At the landscape scale, bat roost-site selection was positively associated with northern mixed forest, increased slope, and greater distance from human development. At the stand scale, we observed subtle differences in roost site selection based on sex and season, but roost selection was generally positively associated with larger stands with a higher basal area, larger tree diameter, and a greater sugar maple (Acer saccharum) component. We observed no distinct trends of roosts being near high-quality foraging areas of water and forest edges. At the tree scale, roosts were typically in American elm (Ulmus americana) or sugar maple of large diameter (>30 cm) of moderate decay with loose bark. Collectively, our results highlight the importance of considering day roost needs simultaneously across multiple spatial scales. Size and decay class of individual roosts are key ecological attributes for the Indiana bat, however, larger-scale stand structural components

  12. Seeing the forest through the trees: Considering roost-site selection at multiple spatial scales

    Science.gov (United States)

    Jachowski, David S.; Rota, Christopher T.; Dobony, Christopher A.; Ford, W. Mark; Edwards, John W.

    2016-01-01

    Conservation of bat species is one of the most daunting wildlife conservation challenges in North America, requiring detailed knowledge about their ecology to guide conservation efforts. Outside of the hibernating season, bats in temperate forest environments spend their diurnal time in day-roosts. In addition to simple shelter, summer roost availability is as critical as maternity sites and maintaining social group contact. To date, a major focus of bat conservation has concentrated on conserving individual roost sites, with comparatively less focus on the role that broader habitat conditions contribute towards roost-site selection. We evaluated roost-site selection by a northern population of federally-endangered Indiana bats (Myotis sodalis) at Fort Drum Military Installation in New York, USA at three different spatial scales: landscape, forest stand, and individual tree level. During 2007–2011, we radiotracked 33 Indiana bats (10 males, 23 females) and located 348 roosting events in 116 unique roost trees. At the landscape scale, bat roost-site selection was positively associated with northern mixed forest, increased slope, and greater distance from human development. At the stand scale, we observed subtle differences in roost site selection based on sex and season, but roost selection was generally positively associated with larger stands with a higher basal area, larger tree diameter, and a greater sugar maple (Acer saccharum) component. We observed no distinct trends of roosts being near high-quality foraging areas of water and forest edges. At the tree scale, roosts were typically in American elm (Ulmus americana) or sugar maple of large diameter (>30 cm) of moderate decay with loose bark. Collectively, our results highlight the importance of considering day roost needs simultaneously across multiple spatial scales. Size and decay class of individual roosts are key ecological attributes for the Indiana bat, however, larger-scale stand structural

  13. Predicting sulfotyrosine sites using the random forest algorithm with significantly improved prediction accuracy

    Directory of Open Access Journals (Sweden)

    Yang Zheng

    2009-10-01

    Full Text Available Abstract Background Tyrosine sulfation is one of the most important posttranslational modifications. Due to its relevance to various disease developments, tyrosine sulfation has become the target for drug design. In order to facilitate efficient drug design, accurate prediction of sulfotyrosine sites is desirable. A predictor published seven years ago has been very successful with claimed prediction accuracy of 98%. However, it has a particularly low sensitivity when predicting sulfotyrosine sites in some newly sequenced proteins. Results A new approach has been developed for predicting sulfotyrosine sites using the random forest algorithm after a careful evaluation of seven machine learning algorithms. Peptides are formed by consecutive residues symmetrically flanking tyrosine sites. They are then encoded using an amino acid hydrophobicity scale. This new approach has increased the sensitivity by 22%, the specificity by 3%, and the total prediction accuracy by 10% compared with the previous predictor using the same blind data. Meanwhile, both negative and positive predictive powers have been increased by 9%. In addition, the random forest model has an excellent feature for ranking the residues flanking tyrosine sites, hence providing more information for further investigating the tyrosine sulfation mechanism. A web tool has been implemented at http://ecsb.ex.ac.uk/sulfotyrosine for public use. Conclusion The random forest algorithm is able to deliver a better model compared with the Hidden Markov Model, the support vector machine, artificial neural networks, and others for predicting sulfotyrosine sites. The success shows that the random forest algorithm together with an amino acid hydrophobicity scale encoding can be a good candidate for peptide classification.

  14. 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.

  15. Empirical test of the influence of global warming and forest disturbance on ant fauna at the Gwangneung Forest Long Term Ecological Research site, South Korea

    Directory of Open Access Journals (Sweden)

    Tae-Sung Kwon

    2014-09-01

    Full Text Available This study examined the effects of forest disturbance and climate change on the ant fauna at the Long Term Ecological Research site in Gwangneung Forest, Korea in 2003 and 2012. After forest disturbance, the occurrence and abundance of ants belonging to the functional groups of forest ground forager and soil and litter dweller are predicted to decrease, while the occurrence and abundance of ants belonging to the open land forager and forest vegetation forager functional groups are predicted to increase. In terms of the effects of climate change, if the optimum temperature of the ants is lower than the annual average temperature in the survey area, the occurrence and abundance of the ants are predicted to decrease and vice versa. Ant surveys were carried out using pitfall traps. Changes in the dominant species, occurrence, and abundance mostly corresponded to the predictions for forest disturbance, but did not match the prediction for an increase in temperature.

  16. Validation of 3D-CMCC Forest Ecosystem Model (v.5.1) against eddy covariance data for 10 European forest sites

    DEFF Research Database (Denmark)

    Collalti, A.; Marconi, S.; Ibrom, Andreas

    2016-01-01

    This study evaluates the performances of the new version (v.5.1) of 3D-CMCC Forest Ecosystem Model (FEM) in simulating gross primary productivity (GPP), against eddy covariance GPP data for 10 FLUXNET forest sites across Europe. A new carbon allocation module, coupled with new both phenological...... over Europe without a site-related calibration, the model has been deliberately parametrized with a single set of species-specific parametrizations for each forest ecosystem. The model consistently reproduces both in timing and in magnitude daily and monthly GPP variability across all sites......, with the exception of the two Mediterranean sites. We find that 3D-CMCC FEM tends to better simulate the timing of inter-annual anomalies than their magnitude within measurements' uncertainty. In six of eight sites where data are available, the model well reproduces the 2003 summer drought event. Finally, for three...

  17. Complex Network Simulation of Forest Network Spatial Pattern in Pearl River Delta

    Science.gov (United States)

    Zeng, Y.

    2017-09-01

    Forest network-construction uses for the method and model with the scale-free features of complex network theory based on random graph theory and dynamic network nodes which show a power-law distribution phenomenon. The model is suitable for ecological disturbance by larger ecological landscape Pearl River Delta consistent recovery. Remote sensing and GIS spatial data are available through the latest forest patches. A standard scale-free network node distribution model calculates the area of forest network's power-law distribution parameter value size; The recent existing forest polygons which are defined as nodes can compute the network nodes decaying index value of the network's degree distribution. The parameters of forest network are picked up then make a spatial transition to GIS real world models. Hence the connection is automatically generated by minimizing the ecological corridor by the least cost rule between the near nodes. Based on scale-free network node distribution requirements, select the number compared with less, a huge point of aggregation as a future forest planning network's main node, and put them with the existing node sequence comparison. By this theory, the forest ecological projects in the past avoid being fragmented, scattered disorderly phenomena. The previous regular forest networks can be reduced the required forest planting costs by this method. For ecological restoration of tropical and subtropical in south China areas, it will provide an effective method for the forest entering city project guidance and demonstration with other ecological networks (water, climate network, etc.) for networking a standard and base datum.

  18. COMPLEX NETWORK SIMULATION OF FOREST NETWORK SPATIAL PATTERN IN PEARL RIVER DELTA

    Directory of Open Access Journals (Sweden)

    Y. Zeng

    2017-09-01

    Full Text Available Forest network-construction uses for the method and model with the scale-free features of complex network theory based on random graph theory and dynamic network nodes which show a power-law distribution phenomenon. The model is suitable for ecological disturbance by larger ecological landscape Pearl River Delta consistent recovery. Remote sensing and GIS spatial data are available through the latest forest patches. A standard scale-free network node distribution model calculates the area of forest network’s power-law distribution parameter value size; The recent existing forest polygons which are defined as nodes can compute the network nodes decaying index value of the network’s degree distribution. The parameters of forest network are picked up then make a spatial transition to GIS real world models. Hence the connection is automatically generated by minimizing the ecological corridor by the least cost rule between the near nodes. Based on scale-free network node distribution requirements, select the number compared with less, a huge point of aggregation as a future forest planning network’s main node, and put them with the existing node sequence comparison. By this theory, the forest ecological projects in the past avoid being fragmented, scattered disorderly phenomena. The previous regular forest networks can be reduced the required forest planting costs by this method. For ecological restoration of tropical and subtropical in south China areas, it will provide an effective method for the forest entering city project guidance and demonstration with other ecological networks (water, climate network, etc. for networking a standard and base datum.

  19. Evaluation of Multiple Spring Phenological Indicators of Yearly GPP and NEP at Three Canadian Forest Sites

    Directory of Open Access Journals (Sweden)

    Qian Wang

    2014-03-01

    Full Text Available Phenological shifts in events such as flowering and bud break are important indicators of ecosystem processes, and are therefore of particular significance for carbon (C cycle research. Using long-term flux data from three contrasting plant functional type (evergreen and deciduous boreal forest sites, we evaluated and compared the responses of annual C fluxes to multiple spring phenological indicators, including the C-uptake period onset (CUP onset, spring temperature (average value from March to May, and satellite-derived enhanced vegetation index (EVI (average value from March to May. We found that the CUP onset was negatively correlated with annual gross primary production (GPP for all three sites, but that its predictive strength for annual net ecosystem production (NEP differed substantially among plant functional types. Spring temperature demonstrated particularly good potential for predicting both annual GPP and NEP for the evergreen sites, but not for the deciduous site. Spring EVI was demonstrated to have potential for predicting annual NEP for all sites. However, both plant functional types confounded the correlation of annual NEP with annual GPP. Although none of these phenological indicators provided consistent insight into annual C fluxes, using various currently available datasets our results remain potentially useful for the assessment of forest C cycling with future climate change. Previous analyses using only a single phenological metric should be considered with caution.

  20. 78 FR 47779 - Rough & Ready Lumber, LLC; Including On-Site Leased Workers From Perpetua Forests Company Cave...

    Science.gov (United States)

    2013-08-06

    ... Perpetua Forests Company Cave Junction, Oregon; Amended Certification Regarding Eligibility To Apply for..., Cave Junction, Oregon (subject firm). The Department's Notice of determination was published in the... workers from Perpetua Forests Company were employed on-site at the Cave Junction, Oregon location of Rough...

  1. In situ soil temperature and heat flux measurements during controlled surface burns at a southern Colorado forest site

    Science.gov (United States)

    W. J. Massman; J. M. Frank; W. D. Shepperd; M. J. Platten

    2003-01-01

    This study presents in situ soil temperature measurements at 5-6 depths and heat flux measurements at 2-5 depths obtained during the fall/winter of 2001/ 2002 at seven controlled (surface) fires within a ponderosa pine forest site at the Manitou Experimental Forest in central Colorado. Six of these burns included three different (low, medium, and high) fuel loadings...

  2. Coordinated fee structure for developed recreation sites on the Ashley, Uinta, and Wasatch-Cache National Forests

    Science.gov (United States)

    Brent H. McBeth

    1995-01-01

    A joint effort between three National Forests in northern Utah was begun to provide a uniform process for establishing fees at developed recreation sites, based upon the "cost approach" method. This method can be adapted for other National Forest and District use and can be modified to reflect "comparable fees" and updated periodically to meet local...

  3. Site index comparisons for forest species in the Upper Great Lakes area of the United States and Canada

    Science.gov (United States)

    Willard H. Carmean; Jerold T. Hahn; Ronald E. McRoberts; D. Kaisershot

    2013-01-01

    This report summarizes six studies that compare site index relations between 24 hardwood and conifer species in the Upper Great Lakes area of the United States and Canada. These six studies have many regression models and graphs for comparing site index between forest species thus providing tools for estimating site index for alternative tree species based on direct...

  4. Complex Resistivity 3D Imaging for Ground Reinforcement Site

    Science.gov (United States)

    Son, J.; Kim, J.; Park, S.

    2012-12-01

    Induced polarization (IP) method is used for mineral exploration and generally classified into two categories, time and frequency domain method. IP method in frequency domain measures amplitude and absolute phase to the transmitted currents, and is often called spectral induced polarization (SIP) when measurement is made for the wide-band frequencies. Our research group has been studying the modeling and inversion algorithms of complex resistivity method since several years ago and recently started to apply this method for various field applications. We already completed the development of 2/3D modeling and inversion program and developing another algorithm to use wide-band data altogether. Until now complex resistivity (CR) method was mainly used for the surface or tomographic survey of mineral exploration. Through the experience, we can find that the resistivity section from CR method is very similar with that of conventional resistivity method. Interpretation of the phase section is generally well matched with the geological information of survey area. But because most of survey area has very touch and complex terrain, 2D survey and interpretation are used generally. In this study, the case study of 3D CR survey conducted for the site where ground reinforcement was done to prevent the subsidence will be introduced. Data was acquired with the Zeta system, the complex resistivity measurement system produced by Zonge Co. using 8 frequencies from 0.125 to 16 Hz. 2D survey was conducted for total 6 lines with 5 m dipole spacing and 20 electrodes. Line length is 95 meter for every line. Among these 8 frequency data, data below 1 Hz was used considering its quality. With the 6 line data, 3D inversion was conducted. Firstly 2D interpretation was made with acquired data and its results were compared with those of resistivity survey. Resulting resistivity image sections of CR and resistivity method were very similar. Anomalies in phase image section showed good agreement

  5. A practical approach for comparing management strategies in complex forest ecosystems using meta-modelling toolkits

    Science.gov (United States)

    Andrew Fall; B. Sturtevant; M.-J. Fortin; M. Papaik; F. Doyon; D. Morgan; K. Berninger; C. Messier

    2010-01-01

    The complexity and multi-scaled nature of forests poses significant challenges to understanding and management. Models can provide useful insights into process and their interactions, and implications of alternative management options. Most models, particularly scientific models, focus on a relatively small set of processes and are designed to operate within a...

  6. ASSESSMENT OF FOREST POND FUNCTION IN DIFFERENT METEOROLOGICAL CONDITIONS AT PROMOTIONAL FOREST COMPLEX AREA OF LASY RYCHTALSKIE

    Directory of Open Access Journals (Sweden)

    Mariusz Tomasz Korytowski

    2016-09-01

    Full Text Available The paper presents the results of the researches carried out in the catchments of pond No 1 and No 6. The ponds are located in Siemianice Experimental Farm, belonging to “Lasy Rychtalskie” Promotional Forest Complex, in Wielisławice (pond No 1 and Laski forestry (pond No 6. The researches were carried out in two hydrological years 2010/2011 and 2012/2013. The years had different precipitation. The area of catchment of pond No 1 is about 7.5 ha and its forestation totals 100%. Whereas catchment area of pond No 6 is about 37 ha. The forestation of this pond is about 40% and the rest are arable areas. The analyzed pond No 1 and 6, have mild scarps, and they are natural pond melting out. The area of pond No 1 is 0.13 ha, whereas pond No 6 is 0.35 ha, and averages depths of both ponds are 1.0 m and 1.4 m. The results confirmed a connection between water in ponds and groundwater in neighboring areas. In some periods water of ponds supply surrounding areas and in some periods on the contrary – groundwater supply water in ponds. Correlation coefficient (from 0.43 to 0.96 calculated for relation between water levels in ponds and groundwater were statistically significant for the level α=0.01 in analyzed hydrological years.

  7. History of the production complex: The methods of site selection

    Energy Technology Data Exchange (ETDEWEB)

    1987-09-01

    Experience taught the Atomic Energy Commission how to select the best possible sites for its production facilities. AEC officials learned from the precedents set by the wartime Manhattan Project and from their own mistakes in the immediate postwar years. This volume discusses several site selections. The sites covered are: (1) the Hanford Reservation, (2) the Idaho reactor site, (3) the Savannah River Plant, (4) the Paducah Gaseous Diffusion Plant, (5) the Portsmouth Gaseous Diffusion Plant, (6) the Fernald Production Center, (7) the PANTEX and Spoon River Plants, (8) the Rocky Flats Fabrication Facility, and (9) the Miamisburg and Pinellas plants. (JDH)

  8. A multi-sites analysis on the ozone effects on Gross Primary Production of European forests

    Energy Technology Data Exchange (ETDEWEB)

    Proietti, C. [Department of Environmental Biology, Sapienza University of Rome, Piazzale Aldo Moro, 5, 00185 Rome (Italy); Anav, A. [Italian National Agency for New Technologies, Energy and the Environment (ENEA), C.R. Casaccia, Via Anguillarese 301, 00123 S. Maria di Galeria, Rome (Italy); University of Exeter, College of Engineering, Mathematics and Physical Sciences, Exeter (United Kingdom); De Marco, A. [Italian National Agency for New Technologies, Energy and the Environment (ENEA), C.R. Casaccia, Via Anguillarese 301, 00123 S. Maria di Galeria, Rome (Italy); Sicard, P. [ACRI-HE, 260 route du Pin Montard BP234, 06904 Sophia Antipolis-cedex (France); Vitale, M., E-mail: marcello.vitale@uniroma1.it [Department of Environmental Biology, Sapienza University of Rome, Piazzale Aldo Moro, 5, 00185 Rome (Italy)

    2016-06-15

    Ozone (O{sub 3}) 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 O{sub 3} can impair CO{sub 2} assimilation that, in turn affects forest productivity. This study aims to evaluate the effects of tropospheric O{sub 3} 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 O{sub 3} monitoring stations (and vice-versa) this study makes a first attempt to combine high resolution MODIS Gross Primary Production (GPP) estimates and O{sub 3} measurement data. Partial Correlations, Anomalies Analysis and the Random Forests Analysis (RFA) were used to quantify the effects of tropospheric O{sub 3} 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 O{sub 3} 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 O{sub 3} ability to reduce primary productivity of the forests, this study can help in assessing the O{sub 3} impacts on ecosystem services, including wood production and carbon sequestration. - Highlights: • Assessment of the surface O{sub 3

  9. Carbon storage as affected by different site preparation techniques two years after mixed forest stand installation

    Directory of Open Access Journals (Sweden)

    Felicia Fonseca

    2014-04-01

    Full Text Available Aim of study: This study aims at evaluating the impact of site preparation techniques prior to plantation on carbon storage and distribution in a young mixed stand of Pseudotsuga menziesii (PM and Castanea sativa (CS. Area of study: The experimental field was established near Macedo de Cavaleiros, Northern Portugal, at 700 m elevation, mean annual temperature 12ºC and mean annual rainfall 678 mm. Material and Methods: The experimental layout includes three replicates, where the different treatments corresponding to different tillage intensities were randomly distributed (high, moderate and slight intensity, in plots with an area of 375 m2 each. Twenty six months after forest stand installation, samples of herbaceous vegetation (0.49 m2 quadrat, forest species (8 PM and 8 CS and mineral soil (at 0-5, 5-15, 15-30 and 30-60 cm depth were collected in 15 randomly selected points in each treatment, processed in laboratory and analyzed for carbon by elemental carbon analyzer. Main results: The results obtained showed that: (i more than 90% of the total carbon stored in the system is located in the soil, increasing in depth with tillage intensity; (ii the contribution of herbaceous vegetation and related roots to the carbon storage is very low; (iii the amount of carbon per tree is higher in CS than in PM; (iv the global carbon storage was affected by soil tillage generally decreasing with the increase of tillage intensity. Accordingly, carbon storage capacity as affected by the application of different site preparation techniques should be a decision support tool in afforestation schemes.Keywords: Site preparation; forest species; herbaceous vegetation; carbon storage; mineral soil; Portugal.

  10. Effects of slope aspect and site elevation on seasonal soil carbon dynamics in a forest catchment in the Austrian Limestone Alps

    Science.gov (United States)

    Kobler, Johannes; Zehetgruber, Bernhard; Jandl, Robert; Dirnböck, Thomas; Schindlbacher, Andreas

    2017-04-01

    Own to the complexity of landscape morphology, mountainous landscapes are characterized by substantial changes of site parameters (i.e. elevation, slope, aspect) within short distances. As these site parameters affect the spatial-temporal dynamics of landscape climate and therefore the spatial patterns of forest carbon (C) distribution, they pose a substantial impact on landscape-related soil C dynamics. Aspect and elevation form natural temperature gradients and thereby can be used as a surrogate to infer to potential climate change effects on forest C. We aimed at studying how slope aspect affected soil respiration, soil C stocks, tree increment and litter production along two elevation gradients in the Zöbelboden catchment, northern limestone Alps, Austria during 2015 and 2016. A preliminary assessment showed that soil respiration was significantly higher at the west facing slope across all elevations. Soil temperature was only slightly higher at the west facing slope, and warmer soil only partly explained the large difference in soil respiration between east and west facing slopes. Aspect had no clear effect on soil moisture, which seemed to be strongly affected by stocking density at the different forest sites. The dense grassy ground vegetation at some of the sites further seems to play a key role in determining soil respiration rates and litter input. A detailed analysis and C-budgets along the elevation gradients will be presented at the conference.

  11. Environmental Controls on Cumulative and Yearly Litter Decay Rates Over Four Years in Forested and Harvested Sites Across Canada

    Science.gov (United States)

    Trofymow, J. A.; Thompson, E.; Cameron, A.; Pare, D.; Amiro, B. D.; Lavigne, M.; Smyth, C.; Black, T. A.; Barr, A. G.; Margolis, H. A.

    2010-12-01

    Decomposition of plant detritus and heterotrophic respiration have been demonstrated to be affected by climate, litter type and soil biota. Clearcut harvest affects site temperature and water balance and theoretically in situ measurements of soil microenvironment and models which include them should better account for variation in soil C fluxes among sites and with disturbance than just aboveground climate. Detrital C fluxes were studied at 16 sites at 7 stations of the Fluxnet Canada Research Network, including paired closed canopy and clearcut forest sites at 5 upland stations (BC, SK, ON, QC, NB). All sites were instrumented for climate and in situ measurements of soil moisture and temperature. Cumulative litter decay was measured using surface placed litterbags with one of four standard material types (aspen leaves AL, black spruce needles BS, Douglas fir needles DF, and birch wood sticks BW). Six replicate plots were located at each site, each plot contained sufficient numbers of surface litterbags of each material to allow for four annual collections. As well unconfined birch chopsticks were placed at three depths down the soil profile (surface, 5cm, 15cm) and replaced annually to examine interannual variability in early phase annual decay. After four years of cumulative decay, litter rank by %mass remaining had AL< BSforests than clearcuts. Within a site annual decay of surface birch sticks was similar with interannual variability less than variability down the soil profile. The effects of clearcut varied with forest site type, on wetter sites surface BW decayed faster in clearcuts than closed forest, however this was reversed in drier forest site types. At lower soil depths on drier sites, decay was more rapid in clearcuts than in the closed forest. Interannual variation in soil moisture accounted for more variability in the annual mass loss than did soil temperature, however the relationship was

  12. Classification and identification of small objects in complex urban-forested LIDAR data using machine learning

    Science.gov (United States)

    Basener, William F.; Basener, Abigail

    2017-05-01

    Classification in LIDAR data is the process of determining points on terrain types and objects, often with the goal of determining land use and/or building footprints. In this paper we endeavor to classify terrain types and objects at a high level of detail in a complex scene that includes buildings, forested areas, and steep hillsides. Our object classes include buildings, building rooftop structures, forest trees, landscape trees, landscape bushes, cars, light posts of varying sizes, fences, paved surfaces, and grass. Our classification method of choice is a Random Forest, but we also investigate other machine learning methods including K-Nearest Neightbors and Linear Discriminant Analysis. We evaluate the effectiveness of the algorithms for accuracy, required training sample size, and runtime.

  13. Comparative phylogeographic analyses illustrate the complex evolutionary history of threatened cloud forests of northern Mesoamerica.

    Science.gov (United States)

    Ornelas, Juan Francisco; Sosa, Victoria; Soltis, Douglas E; Daza, Juan M; González, Clementina; Soltis, Pamela S; Gutiérrez-Rodríguez, Carla; de los Monteros, Alejandro Espinosa; Castoe, Todd A; Bell, Charles; Ruiz-Sanchez, Eduardo

    2013-01-01

    Comparative phylogeography can elucidate the influence of historical events on current patterns of biodiversity and can identify patterns of co-vicariance among unrelated taxa that span the same geographic areas. Here we analyze temporal and spatial divergence patterns of cloud forest plant and animal species and relate them to the evolutionary history of naturally fragmented cloud forests--among the most threatened vegetation types in northern Mesoamerica. We used comparative phylogeographic analyses to identify patterns of co-vicariance in taxa that share geographic ranges across cloud forest habitats and to elucidate the influence of historical events on current patterns of biodiversity. We document temporal and spatial genetic divergence of 15 species (including seed plants, birds and rodents), and relate them to the evolutionary history of the naturally fragmented cloud forests. We used fossil-calibrated genealogies, coalescent-based divergence time inference, and estimates of gene flow to assess the permeability of putative barriers to gene flow. We also used the hierarchical Approximate Bayesian Computation (HABC) method implemented in the program msBayes to test simultaneous versus non-simultaneous divergence of the cloud forest lineages. Our results show shared phylogeographic breaks that correspond to the Isthmus of Tehuantepec, Los Tuxtlas, and the Chiapas Central Depression, with the Isthmus representing the most frequently shared break among taxa. However, dating analyses suggest that the phylogeographic breaks corresponding to the Isthmus occurred at different times in different taxa. Current divergence patterns are therefore consistent with the hypothesis of broad vicariance across the Isthmus of Tehuantepec derived from different mechanisms operating at different times. This study, coupled with existing data on divergence cloud forest species, indicates that the evolutionary history of contemporary cloud forest lineages is complex and often lineage

  14. Comparative phylogeographic analyses illustrate the complex evolutionary history of threatened cloud forests of northern Mesoamerica.

    Directory of Open Access Journals (Sweden)

    Juan Francisco Ornelas

    Full Text Available Comparative phylogeography can elucidate the influence of historical events on current patterns of biodiversity and can identify patterns of co-vicariance among unrelated taxa that span the same geographic areas. Here we analyze temporal and spatial divergence patterns of cloud forest plant and animal species and relate them to the evolutionary history of naturally fragmented cloud forests--among the most threatened vegetation types in northern Mesoamerica. We used comparative phylogeographic analyses to identify patterns of co-vicariance in taxa that share geographic ranges across cloud forest habitats and to elucidate the influence of historical events on current patterns of biodiversity. We document temporal and spatial genetic divergence of 15 species (including seed plants, birds and rodents, and relate them to the evolutionary history of the naturally fragmented cloud forests. We used fossil-calibrated genealogies, coalescent-based divergence time inference, and estimates of gene flow to assess the permeability of putative barriers to gene flow. We also used the hierarchical Approximate Bayesian Computation (HABC method implemented in the program msBayes to test simultaneous versus non-simultaneous divergence of the cloud forest lineages. Our results show shared phylogeographic breaks that correspond to the Isthmus of Tehuantepec, Los Tuxtlas, and the Chiapas Central Depression, with the Isthmus representing the most frequently shared break among taxa. However, dating analyses suggest that the phylogeographic breaks corresponding to the Isthmus occurred at different times in different taxa. Current divergence patterns are therefore consistent with the hypothesis of broad vicariance across the Isthmus of Tehuantepec derived from different mechanisms operating at different times. This study, coupled with existing data on divergence cloud forest species, indicates that the evolutionary history of contemporary cloud forest lineages is complex

  15. Sequence and structural features of binding site residues in protein-protein complexes: comparison with protein-nucleic acid complexes

    Directory of Open Access Journals (Sweden)

    Selvaraj S

    2011-10-01

    Full Text Available Abstract Background Protein-protein interactions are important for several cellular processes. Understanding the mechanism of protein-protein recognition and predicting the binding sites in protein-protein complexes are long standing goals in molecular and computational biology. Methods We have developed an energy based approach for identifying the binding site residues in protein–protein complexes. The binding site residues have been analyzed with sequence and structure based parameters such as binding propensity, neighboring residues in the vicinity of binding sites, conservation score and conformational switching. Results We observed that the binding propensities of amino acid residues are specific for protein-protein complexes. Further, typical dipeptides and tripeptides showed high preference for binding, which is unique to protein-protein complexes. Most of the binding site residues are highly conserved among homologous sequences. Our analysis showed that 7% of residues changed their conformations upon protein-protein complex formation and it is 9.2% and 6.6% in the binding and non-binding sites, respectively. Specifically, the residues Glu, Lys, Leu and Ser changed their conformation from coil to helix/strand and from helix to coil/strand. Leu, Ser, Thr and Val prefer to change their conformation from strand to coil/helix. Conclusions The results obtained in this study will be helpful for understanding and predicting the binding sites in protein-protein complexes.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-03-12

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

  17. Survival and growth of restored Piedmont riparian forests as affected by site preparation, planting stock, and planting aids

    Science.gov (United States)

    Chelsea M. Curtis; W. Michael Aust; John R. Seiler; Brian D. Strahm

    2015-01-01

    Forest mitigation sites may have poor survival and growth of planted trees due to poor drainage, compacted soils, and lack of microtopography. The effects of five replications of five forestry mechanical site preparation techniques (Flat, Rip, Bed, Pit, and Mound), four regeneration sources (Direct seed, Bare root, Tubelings, and Gallon), and three planting aids (None...

  18. A breeding site record of Long-billed Vulture Gyps indicus (Aves: Accipitriformes: Accipitridae from Bejjur Reserve Forest, Telangana, India

    Directory of Open Access Journals (Sweden)

    Swetha Stotrabhashyam

    2015-01-01

    Full Text Available The Long-billed Vulture Gyps indicus is, Critically Endangered with few known breeding sites in peninsular India.  We present a previously undocumented Long-billed Vulture breeding site in Bejjur Reserve Forest, Adilabad District, northern Telangana.

  19. An unsupervised two-stage clustering approach for forest structure classification based on X-band InSAR data - A case study in complex temperate forest stands

    Science.gov (United States)

    Abdullahi, Sahra; Schardt, Mathias; Pretzsch, Hans

    2017-05-01

    Forest structure at stand level plays a key role for sustainable forest management, since the biodiversity, productivity, growth and stability of the forest can be positively influenced by managing its structural diversity. In contrast to field-based measurements, remote sensing techniques offer a cost-efficient opportunity to collect area-wide information about forest stand structure with high spatial and temporal resolution. Especially Interferometric Synthetic Aperture Radar (InSAR), which facilitates worldwide acquisition of 3d information independent from weather conditions and illumination, is convenient to capture forest stand structure. This study purposes an unsupervised two-stage clustering approach for forest structure classification based on height information derived from interferometric X-band SAR data which was performed in complex temperate forest stands of Traunstein forest (South Germany). In particular, a four dimensional input data set composed of first-order height statistics was non-linearly projected on a two-dimensional Self-Organizing Map, spatially ordered according to similarity (based on the Euclidean distance) in the first stage and classified using the k-means algorithm in the second stage. The study demonstrated that X-band InSAR data exhibits considerable capabilities for forest structure classification. Moreover, the unsupervised classification approach achieved meaningful and reasonable results by means of comparison to aerial imagery and LiDAR data.

  20. Atmospheric particulate mercury at the urban and forest sites in central Poland.

    Science.gov (United States)

    Siudek, Patrycja; Frankowski, Marcin; Siepak, Jerzy

    2016-02-01

    Particulate mercury concentrations were investigated during intensive field campaigns at the urban and forest sites in central Poland, between April 2013 and October 2014. For the first time, quantitative determination of total particulate mercury in coarse (PHg2.2) and fine (PHg0.7) aerosol samples was conducted in Poznań and Jeziory. The concentrations in urban fine and coarse aerosol fractions amounted to urban site during summer was mainly attributed to anthropogenic sources, with significant contribution from resuspension processes and long-range transport. The highest values of PHg0.7 and PHg2.2 were found during westerly and southerly wind events, reflecting local emission from highly polluted areas. The period from late fall to spring showed that advection from the southern part of Poland was the main factor responsible for elevated Hg concentrations in fine and coarse particles in the investigated region. Moreover, September 2013 could be given as an example of the influence of additional urban activities which occurred approx. 10 m from the sampling site-construction works connected with replacement of the road surface, asphalting, etc. The concentrations of particulate Hg (>600.0 pg m(-3)) were much higher than during the following months when any similar situation did not occur. Our investigations confirmed that Hg in urban aerosol samples was predominantly related to local industrial and commercial emissions, whereas the main source of Hg in particulate matter collected at the forest site was connected with regional anthropogenic processes. This paper provides the results of the first long-term measurements of size-fractionated particulate mercury conducted in central Poland, which could be an important insight into atmospheric Hg processes within such a scarcely investigated part of Europe.

  1. Sources of long-lived atmospheric VOCs at the rural boreal forest site, SMEAR II

    Science.gov (United States)

    Patokoski, J.; Ruuskanen, T. M.; Kajos, M. K.; Taipale, R.; Rantala, P.; Aalto, J.; Ryyppö, T.; Nieminen, T.; Hakola, H.; Rinne, J.

    2015-12-01

    In this study a long-term volatile organic compound (VOCs) concentration data set, measured at the SMEAR II (Station for Measuring Ecosystem-Atmosphere Relations) boreal forest site in Hyytiälä, Finland during the years 2006-2011, was analyzed in order to identify source areas and profiles of the observed VOCs. VOC mixing ratios were measured using proton transfer reaction mass spectrometry. Four-day HYSPLIT 4 (Hybrid Single Particle Lagrangian Integrated Trajectory) backward trajectories and the Unmix 6.0 receptor model were used for source area and source composition analysis. Two major forest fire events in Russia took place during the measurement period. The effect of these fires was clearly visible in the trajectory analysis, lending confidence to the method employed with this data set. Elevated volume mixing ratios (VMRs) of non-biogenic VOCs related to forest fires, e.g. acetonitrile and aromatic VOCs, were observed. Ten major source areas for long-lived VOCs (methanol, acetonitrile, acetaldehyde, acetone, benzene, and toluene) observed at the SMEAR II site were identified. The main source areas for all the targeted VOCs were western Russia, northern Poland, Kaliningrad, and the Baltic countries. Industrial areas in northern continental Europe were also found to be source areas for certain VOCs. Both trajectory and receptor analysis showed that air masses from northern Fennoscandia were less polluted with respect to both the VOCs studied and other trace gases (CO, SO2 and NOx), compared to areas of eastern and western continental Europe, western Russia, and southern Fennoscandia.

  2. Proposal - FY15 - Baseline Measurements on Continuous Forest Inventory (CFI) Plots on Atchafalaya NWR (ANWR), Southeast Louisiana Refuges Complex

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The proposal involves the establishment of permanent continuous forest inventory plots at Atchafalaya National Wildlife Refuge. At each site, 5 nested, 1/5 acre...

  3. Aboveground-Biomass Estimation of a Complex Tropical Forest in India Using Lidar

    Directory of Open Access Journals (Sweden)

    Cédric Véga

    2015-08-01

    Full Text Available Light Detection and Ranging (Lidar is a state of the art technology to assess forest aboveground biomass (AGB. To date, methods developed to relate Lidar metrics with forest parameters were built upon the vertical component of the data. In multi-layered tropical forests, signal penetration might be restricted, limiting the efficiency of these methods. A potential way for improving AGB models in such forests would be to combine traditional approaches by descriptors of the horizontal canopy structure. We assessed the capability and complementarity of three recently proposed methods for assessing AGB at the plot level using point distributional approach (DM, canopy volume profile approach (CVP, 2D canopy grain approach (FOTO, and further evaluated the potential of a topographical complexity index (TCI to explain part of the variability of AGB with slope. This research has been conducted in a mountainous wet evergreen tropical forest of Western Ghats in India. AGB biomass models were developed using a best subset regression approach, and model performance was assessed through cross-validation. Results demonstrated that the variability in AGB could be efficiently captured when variables describing both the vertical (DM or CVP and horizontal (FOTO structure were combined. Integrating FOTO metrics with those of either DM or CVP decreased the root mean squared error of the models by 4.42% and 6.01%, respectively. These results are of high interest for AGB mapping in the tropics and could significantly contribute to the REDD+ program. Model quality could be further enhanced by improving the robustness of field-based biomass models and influence of topography on area-based Lidar descriptors of the forest structure.

  4. Sustainable forest management of Natura 2000 sites: a case study from a private forest in the Romanian Southern Carpathians

    Directory of Open Access Journals (Sweden)

    Helge Walentowski

    2013-07-01

    Full Text Available Biodiversity and forest management are analyzed for a 500 ha privately owned forest within the Natura 2000 area “ROSCI0122 Muntii Fagaras”. Habitat types and indicator species are identified to measure environmental quality. Working towards an integrated approach to conservation, a range of options that will result in sustainable forest management are then considered. For beech forests light heterogeneity emerges as a crucial management target to ensure tree species richness and structural diversity as a basis for saving indicator species such as Morimus funereus, Cucujus cinnaberinus, Bolitophagus reticulatus and Xestobium austriacum. For spruce forests thinning over a broad range of diameters and maintenance of veteran trees would provide habitats for indicator species such asOlisthaerus substriatus. The populations of a number of bird species would be increased by strip-harvesting slopes: species such as Tetrao urogallus, Bonasia bonasia and Ficedula parva prefer forest margins. Steep slopes, and the areas around springs and watercourses, as well as rock faces, should remain unmanaged. Future management should start with a grid-based inventory to create an objective database of forest structure and life. An example is presented for high-elevation spruce forest. The inventory should quantify the variations in diameter, height and volume of trees per unit area. Such data would allow the advanced planning of forest operations. We discuss a wide range of administrative and organizational changes; changes that are needed for the sustainable forest management of the vast close-to-natural forests of the Muntii Fagaras, the maintenance of the Nardusgrasslands and the protection of wetland vegetation around springs and streams in this Natura 2000-area. 

  5. Thinning, Age, and Site Quality Influence Live Tree Carbon Stocks in Upland Hardwood Forests of the Southern Appalachians

    Science.gov (United States)

    Tara L. Keyser; Stanley J. Zarnoch

    2012-01-01

    This study examines the effects of thinning, age, and site quality on aboveground live tree carbon (ATC) (Mg/ha) stocks in upland hardwood forests of mixed-species composition in the southern Appalachian Mountains. In 1974, 80 plots ranging in size from 0.06 to 0.1 ha were established in even-aged, mixed-hardwood forests throughout the southern Appalachians. All trees...

  6. Ten-year variability in fluxes, meteorology, and environmental conditions at a Colorado subalpine forest site

    Science.gov (United States)

    Burns, S. P.; Turnipseed, A.; Bowling, D. R.; Hu, J.; Monson, R. K.

    2009-12-01

    Changing meteorological and environmental conditions affect fluxes; model analysis has shown that environmental variability directly accounts for about half the interannual variability in net ecosystem exchange (NEE) of CO2 whereas the other 50% is due to biotic responses to these changing variables (Richardson et al. 2007). In our study, ten years (1998-2008) of turbulent flux measurements of heat, water vapor, and CO2 at the Niwot Ridge AmeriFlux site (Monson et al. 2002) are examined with respect to meteorological conditions (atmospheric temperature, stability, precipitation, and cloudiness) as well as changes in environmental conditions, such as snow depth and soil moisture. The typical yearly cycle and an estimate of the magnitude of year-to-year variability in the diurnal fluxes and other variables for a high-elevation subalpine forest ecosystem are presented. Wintertime ecosystem respiration has an average 30-min NEE of 0.62 μmol m-2 s-1 with an interannual range between 0.5-1 μmol m-2 s-1. Uptake of CO2 in late summer has an average NEE of -0.71 μmol m-2 s-1 with an interannual range between -0.1 to -1.5 μmol m-2 s-1. Previous studies at the Niwot Ridge AmeriFlux site have described the importance of photosynthetic photon flux density (PPFD) (Monson et al. 2002) and also growing season length (Hu et al. 2009) on NEE. Water isotope ratios analyzed by Hu et al. (2009) have shown that trees at the site primarily rely on water from snowmelt to sustain them throughout the summer; combining this result with the SIPNET model, Hu et al. conclude that there is a limited connection between summer precipitation and the cumulative annual gross primary production (GPP). We have tested this conclusion more explicitly by examining the response of NEE to specific precipitation events and the effect of extended dry periods on the diel cycle of the fluxes, CO2 mole fraction, sap flow, and other meteorological and soil variables. Additionally, we examine the connection

  7. Determination of the Sites with Conservation Priority in Research Forests of Yasouj University Based on Physiographic Factors

    Directory of Open Access Journals (Sweden)

    R. Zolfaghari

    2013-03-01

    Full Text Available Regarding high economic and conservative values of Zagros forests, and livelihood dependency of local people these recourses, determination of sites with higher conservation index can help us to maintain biodiversity of these forests more efficiently. Therefore, 49 plots with 450 m2 in area accompanied by 1, 10 and 45 m2 subplots were taken as systematic random design in research forests of Yasouj University. The number of species in each plot and subplot was recorded. The conservation values for different physiographic regions of forest were calculated using integrative parameters such as the number of species per plot, number of rare species per plot, number of tree species per plot, Jaccards similarity coefficient and slope of species-log(area. Comparing the conservation index in different physiographic sites revealed that the areas located in the north, hills and lower altitudes can be considered for in situ conservation due to higher number of trees, rare species and total plant species, species-log (area slope and lower amount of Jaccard similarity coefficient. But, vegetative sites located in lower slopes and south, because of lower conservation index, can be used for other multipurpose forestry activities. Using this index for different forest areas can be potentially conducted for better conservation and management of Zagros forests.

  8. Sustainable forest management of Natura 2000 sites: a case study from a private forest in the Romanian Southern Carpathians

    Directory of Open Access Journals (Sweden)

    H. Walentowski

    2013-05-01

    Full Text Available Biodiversity and forest management are analyzed for a 500 haprivately owned forest within the Natura 2000 area “ROSCI0122 MunţiiFăgăraş”. Habitat types and indicator species are identified to measure environmental quality. Working towards an integrated approach to conservation, a range of options that will result in sustainable forest management are then considered. For beech forests light heterogeneity emerges as a crucial management target to ensure tree species richness and structural diversity as a basis for saving indicator species such as Morimus funereus, Cucujus cinnaberinus,Bolitophagus reticulatus and Xestobium austriacum. For spruceforests thinning over a broad range of diameters and maintenance of veteran trees would provide habitats for indicator species such as Olisthaerus substriatus. The populations of a number of bird species would be increased by strip-harvesting slopes: species such as Tetrao urogallus, Bonasia bonasia and Ficedula parva prefer forest margins. Steep slopes, and the areas around springs and watercourses, as well as rock faces, should remain unmanaged. Future management should start with a grid-based inventory to create an objective database of forest structure and life. An example is presented for high-elevation spruce forest. The inventory should quantify the variations in diameter, height and volume of trees per unit area. Such data would allowthe advanced planning of forest operations. We discuss a wide range ofadministrative and organizational changes; changes that are needed for the sustainable forest management of the vast close-to-natural forests of the Munţii Făgăraş, the maintenance of the Nardus grasslands and the protection of wetland vegetation around springs and streams in this Natura 2000-area.

  9. Mapping forest stand complexity for woodland caribou habitat assessment using multispectral airborne imagery

    Science.gov (United States)

    Zhang, W.; Hu, B.; Woods, M.

    2014-11-01

    The decline of the woodland caribou population is a result of their habitat loss. To conserve the habitat of the woodland caribou and protect it from extinction, it is critical to accurately characterize and monitor its habitat. Conventionally, products derived from low to medium spatial resolution remote sensing data, such as land cover classification and vegetation indices are used for wildlife habitat assessment. These products fail to provide information on the structure complexities of forest canopies which reflect important characteristics of caribou's habitats. Recent studies have employed the LiDAR system (Light Detection And Ranging) to directly retrieve the three dimensional forest attributes. Although promising results have been achieved, the acquisition cost of LiDAR data is very high. In this study, utilizing the very high spatial resolution imagery in characterizing the structural development the of forest canopies was exploited. A stand based image texture analysis was performed to predict forest succession stages. The results were demonstrated to be consistent with those derived from LiDAR data.

  10. A forest-based feature screening approach for large-scale genome data with complex structures.

    Science.gov (United States)

    Wang, Gang; Fu, Guifang; Corcoran, Christopher

    2015-12-23

    Genome-wide association studies (GWAS) interrogate large-scale whole genome to characterize the complex genetic architecture for biomedical traits. When the number of SNPs dramatically increases to half million but the sample size is still limited to thousands, the traditional p-value based statistical approaches suffer from unprecedented limitations. Feature screening has proved to be an effective and powerful approach to handle ultrahigh dimensional data statistically, yet it has not received much attention in GWAS. Feature screening reduces the feature space from millions to hundreds by removing non-informative noise. However, the univariate measures used to rank features are mainly based on individual effect without considering the mutual interactions with other features. In this article, we explore the performance of a random forest (RF) based feature screening procedure to emphasize the SNPs that have complex effects for a continuous phenotype. Both simulation and real data analysis are conducted to examine the power of the forest-based feature screening. We compare it with five other popular feature screening approaches via simulation and conclude that RF can serve as a decent feature screening tool to accommodate complex genetic effects such as nonlinear, interactive, correlative, and joint effects. Unlike the traditional p-value based Manhattan plot, we use the Permutation Variable Importance Measure (PVIM) to display the relative significance and believe that it will provide as much useful information as the traditional plot. Most complex traits are found to be regulated by epistatic and polygenic variants. The forest-based feature screening is proven to be an efficient, easily implemented, and accurate approach to cope whole genome data with complex structures. Our explorations should add to a growing body of enlargement of feature screening better serving the demands of contemporary genome data.

  11. Ozone concentrations at a selected high-elevation forest site downwind Mexico City

    Science.gov (United States)

    Torres-JArdon, R.

    2013-05-01

    Torres-Jardón, R.*, Rosas-Pérez, I., Granada-Macías, L. M., Ruiz-Suárez, L. G. Centro de Ciencias de la Atmósfera, UNAM, México D. F. México * rtorres@unam.mx For many years, the vegetation of forest species such as Abies religiosa in natural parks located in the southwest mountains of Mexico City has attracted much attention since these parks have been experiencing a severe decline of unclear etiology. The high ozone levels in the area and the observed naked eye macroscopic, histological and cytological injuries on these species, strongly suggest an important contribution of tropospheric ozone to this deterioration process. Apart of historical short monitoring campaigns for measuring ozone levels in these mountains, it is known just a little is known about the present exposure levels at which the local vegetation is exposed. A continuous ozone analyzer has been in operation since 2011 at a high-elevation forest site (Parque Nacional Miguel Hidalgo, PNMH; 3110 m above mean sea level) located downwind of Mexico City Metropolitan Area (MCMA), in order to characterize the local ozone diel amplitude and its seasonal trend, as well as the influence of MCMA on the local O3 concentrations. Hourly average ozone data in PNMH shows that in general, the diel of ozone concentrations in the forest site has a statistical significant correlation with the pattern of ozone levels observed in several monitoring sites (smog receptor sites) within the MCMA, although the high elevation O3 levels are relatively lower than those in the urban area (around 2200 m above mean sea level). It is possible that a part of the oxidants in the air masses are removed by sink deposition processes during the air mass transport across the hills. The diel amplitude of ozone concentrations is small in the cold season, increasing as the seasons advance to June. As in the city, the highest ozone concentrations occur in April or May and the lowest levels during the rainy season, which extends from

  12. Drivers of community assembly in tropical forest restoration sites: role of local environment, landscape, and space.

    Science.gov (United States)

    Audino, Lívia D; Murphy, Stephen J; Zambaldi, Ludimila; Louzada, Julio; Comita, Liza S

    2017-09-01

    There is increasing recognition that community assembly theory can offer valuable insights for ecological restoration. We studied community assembly processes following tropical forest restoration efforts, using dung beetles (Scarabaeinae) as a focal taxon to investigate taxonomic and functional patterns of biodiversity recovery. We evaluated the relative importance of the local environment (i.e., canopy cover, understory cover, tree basal area, and soil texture), landscape context (i.e., habitat patch proximity and availability and percentage of surrounding area classified as natural forest or Eucalyptus spp. plantation), and space (i.e., spatial proximity of the study areas to estimate dispersal limitation or unmeasured spatially structured processes) on dung beetle species and functional trait composition across a gradient of 15 restoration sites in Brazilian Atlantic Forest. We also assessed which factors were the primary determinants in the establishment of individual dung beetle functional groups, classified according to size, food relocation habit, diet, and period of flight activity. Both species and functional trait composition were most strongly influenced by the local environment, indicating that assembly was predominantly driven by niche-based processes. Most of the variation explained by space was co-explained by local environment and landscape context, ruling out a strong influence of dispersal limitation and random colonization on assembly following restoration. In addition, nearly all of the variance explained by landscape context was co-explained by local environment, suggesting that arrival and establishment at a site depends on both local and landscape-scale environmental factors. Despite strong evidence for niche-based assembly, a large amount of variation remained unexplained in all models, suggesting that stochastic processes and/or unmeasured environmental variables also play an important role. The relative importance of local environment

  13. Birds and bats reduce insect biomass and leaf damage in tropical forest restoration sites.

    Science.gov (United States)

    Morrison, Emily B; Lindell, Catherine A

    2012-07-01

    Both birds and bats are important insect predators in tropical systems. However, the relative influence of birds and bats on insect populations and their indirect effects on leaf damage have not previously been investigated in tropical forest restoration sites. Leaf damage by herbivorous insects can negatively affect the growth and survival of tropical plants and thus can influence the success of tropical forest restoration efforts. We used an exclosure experiment to examine the top-down effects of birds and bats on insects and leaf damage in a large-scale forest restoration experiment. Given the potential influence of tree planting design on bird and bat abundances, we also investigated planting design effects on bird and bat insectivory and leaf damage. The experiment included two planting treatment plots: islands, where trees were planted in patches, and plantations, where trees were planted in rows to create continuous cover. In both types of plots, insect biomass was highest on tree branches where both birds and bats were excluded from foraging and lowest on branches without exclosures where both birds and bats were present. In the island plots, birds and bats had approximately equal impacts on insect populations, while in plantations bats appeared to have a slightly stronger effect on insects than did birds. In plantations, the levels of leaf damage were higher on branches where birds and bats were excluded than on branches where both had access. In island plots, no significant differences in leaf damage were found between exclosure treatments although potential patterns were in the same direction as in the plantations. Our results suggest that both birds and bats play important roles as top predators in restoration systems by reducing herbivorous insects and their damage to planted trees. Tropical restoration projects should include efforts to attract and provide suitable habitat for birds and bats, given their demonstrated ecological importance.

  14. Composition, complexity, and tree mortality in riparian forests in the central Western Cascades of Oregon

    Science.gov (United States)

    Acker, Steve A.; Gregory, S.V.; Lienkaemper, G.; McKee, W.A.; Swanson, F.J.; Miller, S.D.

    2003-01-01

    Riparian forests contribute to the diversity and function of both terrestrial and aquatic ecosystems. To assess some of these contributions, we compared tree composition, stand complexity, and temporal patterns of tree mortality on permanent plots in seven mature and old-growth stands representing upland forests and forests along low- and mid-order streams in the Western Cascade Range of Oregon. We also assessed recruitment of large wood into stream channels due to tree mortality, both by direct measurement and by estimation from tree mortality and location data. Stands differed in composition due to both stream order and successional stage. Stands on mid-order streams had high abundance of hardwood trees and/or Thuja plicata. Stand complexity (variability in tree diameters, tree life-form diversity, and tree species diversity), was high in stands on mid-order streams and in the upland, old-growth stand. Tree mortality was exceptionally high in six of the seven stands in 1996, the year in which the largest flood during the study occurred. However, only in the one stand on an unconstrained reach of a mid-order stream was mortality primarily due to flooding. Estimated recruitment of wood was much higher from the stand on the unconstrained reach than from the other stands on mid-order streams, suggesting that unconstrained reaches may be important for efforts to maintain or restore large wood in streams.

  15. Sleeping site ecology in a rain-forest dwelling nocturnal lemur (Lepilemur mustelinus): implications for sociality and conservation.

    Science.gov (United States)

    Rasoloharijaona, Solofonirina; Randrianambinina, Blanchard; Zimmermann, Elke

    2008-03-01

    Suitable sleeping sites as potentially restricted resources are suggested to shape sociality in primates. We investigated sleeping site ecology of a rain-forest dwelling sportive lemur in eastern Madagascar for the first time. Using radiotelemetry, we characterized the type, quality and usage of sleeping sites as well as social sleeping habits of 11 focal individuals of the weasel sportive lemur (Lepilemur mustelinus) during the dry and the onset of the rainy season. Morphometric measurements provided additional information. The sexes showed an unusual sexual dimorphism for primates. Males and females did not differ in body length, but females surpassed males in body mass suggesting female dominance. Both sexes used dense vegetation and holes in hollow trees high above the ground as shelters for sleeping during the day. No sex difference in the quality of tree holes was found, but focal individuals used tree holes more often than open sleeping sites in dense vegetation. Both sexes showed high sleeping site fidelity limited to two to six different sites that they used primarily solitarily. The results imply that suitable sleeping sites are limited and survival of this species will strongly depend on the availability of mature rain forests with suitable hollow trees. Furthermore, these findings provide evidence of a solitary sleeping and ranging system in this rain-forest dwelling sportive lemur with suitable sleeping sites as defendable resources.

  16. Parameter optimization, sensitivity, and uncertainty analysis of an ecosystem model at a forest flux tower site in the United States

    Science.gov (United States)

    Wu, Yiping; Liu, Shuguang; Huang, Zhihong; Yan, Wende

    2014-01-01

    Ecosystem models are useful tools for understanding ecological processes and for sustainable management of resources. In biogeochemical field, numerical models have been widely used for investigating carbon dynamics under global changes from site to regional and global scales. However, it is still challenging to optimize parameters and estimate parameterization uncertainty for complex process-based models such as the Erosion Deposition Carbon Model (EDCM), a modified version of CENTURY, that consider carbon, water, and nutrient cycles of ecosystems. This study was designed to conduct the parameter identifiability, optimization, sensitivity, and uncertainty analysis of EDCM using our developed EDCM-Auto, which incorporated a comprehensive R package—Flexible Modeling Framework (FME) and the Shuffled Complex Evolution (SCE) algorithm. Using a forest flux tower site as a case study, we implemented a comprehensive modeling analysis involving nine parameters and four target variables (carbon and water fluxes) with their corresponding measurements based on the eddy covariance technique. The local sensitivity analysis shows that the plant production-related parameters (e.g., PPDF1 and PRDX) are most sensitive to the model cost function. Both SCE and FME are comparable and performed well in deriving the optimal parameter set with satisfactory simulations of target variables. Global sensitivity and uncertainty analysis indicate that the parameter uncertainty and the resulting output uncertainty can be quantified, and that the magnitude of parameter-uncertainty effects depends on variables and seasons. This study also demonstrates that using the cutting-edge R functions such as FME can be feasible and attractive for conducting comprehensive parameter analysis for ecosystem modeling.

  17. Parameter optimization, sensitivity, and uncertainty analysis of an ecosystem model at a forest flux tower site in the United States

    Science.gov (United States)

    Wu, Yiping; Liu, Shuguang; Huang, Zhihong; Yan, Wende

    2014-06-01

    Ecosystem models are useful tools for understanding ecological processes and for sustainable management of resources. In biogeochemical field, numerical models have been widely used for investigating carbon dynamics under global changes from site to regional and global scales. However, it is still challenging to optimize parameters and estimate parameterization uncertainty for complex process-based models such as the Erosion Deposition Carbon Model (EDCM), a modified version of CENTURY, that consider carbon, water, and nutrient cycles of ecosystems. This study was designed to conduct the parameter identifiability, optimization, sensitivity, and uncertainty analysis of EDCM using our developed EDCM-Auto, which incorporated a comprehensive R package—Flexible Modeling Framework (FME) and the Shuffled Complex Evolution (SCE) algorithm. Using a forest flux tower site as a case study, we implemented a comprehensive modeling analysis involving nine parameters and four target variables (carbon and water fluxes) with their corresponding measurements based on the eddy covariance technique. The local sensitivity analysis shows that the plant production-related parameters (e.g., PPDF1 and PRDX) are most sensitive to the model cost function. Both SCE and FME are comparable and performed well in deriving the optimal parameter set with satisfactory simulations of target variables. Global sensitivity and uncertainty analysis indicate that the parameter uncertainty and the resulting output uncertainty can be quantified, and that the magnitude of parameter-uncertainty effects depends on variables and seasons. This study also demonstrates that using the cutting-edge R functions such as FME can be feasible and attractive for conducting comprehensive parameter analysis for ecosystem modeling.

  18. A Comparison of Simulated and Field-Derived Leaf Area Index (LAI and Canopy Height Values from Four Forest Complexes in the Southeastern USA

    Directory of Open Access Journals (Sweden)

    John S. Iiames

    2018-01-01

    Full Text Available Vegetative leaf area is a critical input to models that simulate human and ecosystem exposure to atmospheric pollutants. Leaf area index (LAI can be measured in the field or numerically simulated, but all contain some inherent uncertainty that is passed to the exposure assessments that use them. LAI estimates for minimally managed or natural forest stands can be particularly difficult to develop as a result of interspecies competition, age and spatial distribution. Satellite-based LAI estimates hold promise for retrospective analyses, but we must continue to rely on numerical models for alternative management analysis. Our objective for this study is to calculate and validate LAI estimates generated from the USDA Environmental Policy Impact Climate (EPIC model (a widely used, field-scale, biogeochemical model on four forest complexes spanning three physiographic provinces in Virginia and North Carolina. Measurements of forest composition (species and number, LAI, tree diameter, basal area, and canopy height were recorded at each site during the 2002 field season. Calibrated EPIC results show stand-level temporally resolved LAI estimates with R2 values ranging from 0.69 to 0.96, and stand maximum height estimates within 20% of observation. This relatively high level of performance is attributable to EPIC’s approach to the characterization of forest stand biogeochemical budgets, stand history, interspecies competition and species-specific response to local weather conditions. We close by illustrating the extension of this site-level approach to scales that could support regional air quality model simulations.

  19. Classifying Complex Mountainous Forests with L-Band SAR and Landsat Data Integration: A Comparison among Different Machine Learning Methods in the Hyrcanian Forest

    Directory of Open Access Journals (Sweden)

    Sara Attarchi

    2014-04-01

    Full Text Available Forest environment classification in mountain regions based on single-sensor remote sensing approaches is hindered by forest complexity and topographic effects. Temperate broadleaf forests in western Asia such as the Hyrcanian forest in northern Iran have already suffered from intense anthropogenic activities. In those regions, forests mainly extend in rough terrain and comprise different stand structures, which are difficult to discriminate. This paper explores the joint analysis of Landsat7/ETM+, L-band SAR and their derived parameters and the effect of terrain corrections to overcome the challenges of discriminating forest stand age classes in mountain regions. We also verified the performances of three machine learning methods which have recently shown promising results using multisource data; support vector machines (SVM, neural networks (NN, random forest (RF and one traditional classifier (i.e., maximum likelihood classification (MLC as a benchmark. The non-topographically corrected ETM+ data failed to differentiate among different forest stand age classes (average classification accuracy (OA = 65%. This confirms the need to reduce relief effects prior data classification in mountain regions. SAR backscattering alone cannot properly differentiate among different forest stand age classes (OA = 62%. However, textures and PolSAR features are very efficient for the separation of forest classes (OA = 82%. The highest classification accuracy was achieved by the joint usage of SAR and ETM+ (OA = 86%. However, this shows a slight improvement compared to the ETM+ classification (OA = 84%. The machine learning classifiers proved t o be more robust and accurate compared to MLC. SVM and RF statistically produced better classification results than NN in the exploitation of the considered multi-source data.

  20. LBA-ECO TG-07 Forest Soil P, C, and N Pools, km 83 Site, Tapajos National Forest

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set reports phosphorus (P), carbon (C), and nitrogen (N) nutrient pool concentrations for forest soils and roots and P pool concentrations for...

  1. Carbon storage as affected by different site preparation techniques two years after mixed forest stand installation

    Energy Technology Data Exchange (ETDEWEB)

    Fonseca, F.; Figueiredo, T. de; Martins, A.

    2014-06-01

    Aim of study: This study aims at evaluating the impact of site preparation techniques prior to plantation on carbon storage and distribution in a young mixed stand of Pseudotsuga menziesii (PM) and Castanea sativa (CS). Area of study: The experimental field was established near Macedo de Cavaleiros, Northern Portugal, at 700 m elevation, mean annual temperature 12 degree centigrade and mean annual rainfall 678 mm. Material and methods: The experimental layout includes three replicates, where the different treatments corresponding to different tillage intensities were randomly distributed (high, moderate and slight intensity), in plots with an area of 375 m{sup 2} each. Twenty six months after forest stand installation, samples of herbaceous vegetation (0.49 m{sup 2} quadrat), forest species (8 PM and 8 CS) and mineral soil (at 0-5, 5-15, 15-30 and 30-60 cm depth) were collected in 15 randomly selected points in each treatment, processed in laboratory and analyzed for carbon by elemental carbon analyzer. Main results: The results obtained showed that: (i) more than 90% of the total carbon stored in the system is located in the soil, increasing in depth with tillage intensity; (ii) the contribution of herbaceous vegetation and related roots to the carbon storage is very low; (iii) the amount of carbon per tree is higher in CS than in PM; (iv) the global carbon storage was affected by soil tillage generally decreasing with the increase of tillage intensity. Accordingly, carbon storage capacity as affected by the application of different site preparation techniques should be a decision support tool in afforestation schemes. (Author)

  2. Multiple satellite-based analysis reveals complex climate effects of temperate forests and related energy budget

    Science.gov (United States)

    Ma, Wei; Jia, Gensuo; Zhang, Anzhi

    2017-04-01

    Forest conversion-driven biophysical processes have been examined in various case studies that largely depend on sensitivity analysis of climate modeling. However, much remains unknown in the real world due to the complicated process and uncertainty in magnitude, especially in the temperate bioclimate regions. This study applied satellite-based observation to investigate the biophysical climate response to potential forest conversion in China, especially on the spatial and temporal patterns and underlying mechanisms. We evaluated the differences of land surface temperature (ΔLST) between adjacent forest and cropland, in terms of the latitudinal and seasonal patterns. Compared to cropland, the temperate forest to the south of 40°N showed the cooling effect of -0.61 ± 0.02°C (95% confidence interval, and hereafter), and it presented the warming effect of 0.48 ± 0.06°C to the north of 48°N (the transition zone was between 40°N and 48°N). Seasonal analysis further demonstrated that the cooling effects of temperate forest in China in spring (March, April, May), summer (June, July, August), and autumn (September, October, November) were -0.53 ± 0.02°C, -0.55 ± 0.02°C, and -0.30 ± 0.02°C, respectively, while the forest caused the warming effect of 0.10 ± 0.04°C in winter (December, January, February). However, the biophysical climate response to forest conversion in temperate regions was complex and showed highly spatial and temporal heterogeneity. We further assessed the role of two major biophysical processes, i.e., albedo and evapotranspiration (ET), in shaping land surface temperature from surface energy budget perspective. Results showed that the latitudinal, seasonal, and spatiotemporal patterns of ΔLST was determined by the net effect of ET-induced latent heat changes and albedo-induced solar radiation absorption changes.

  3. Technical note: Application of geophysical tools for tree root studies in forest ecosystems in complex soils

    Science.gov (United States)

    Rodríguez-Robles, Ulises; Arredondo, Tulio; Huber-Sannwald, Elisabeth; Alfredo Ramos-Leal, José; Yépez, Enrico A.

    2017-11-01

    While semiarid forests frequently colonize rocky substrates, knowledge is scarce on how roots garner resources in these extreme habitats. The Sierra San Miguelito Volcanic Complex in central Mexico exhibits shallow soils and impermeable rhyolitic-rock outcrops, which impede water movement and root placement beyond the soil matrix. However, rock fractures, exfoliated rocks and soil pockets potentially permit downward water percolation and root growth. With ground-penetrating radar (GPR) and electrical resistivity tomography (ERT), two geophysical methods advocated by Jayawickreme et al. (2014) to advance root ecology, we advanced in the method development studying root and water distribution in shallow rocky soils and rock fractures in a semiarid forest. We calibrated geophysical images with in situ root measurements, and then extrapolated root distribution over larger areas. Using GPR shielded antennas, we identified both fine and coarse pine and oak roots from 0.6 to 7.5 cm diameter at different depths into either soil or rock fractures. We also detected, trees anchoring their trunks using coarse roots underneath rock outcroppings. With ERT, we tracked monthly changes in humidity at the soil-bedrock interface, which clearly explained spatial root distribution of both tree species. Geophysical methods have enormous potential in elucidating root ecology. More interdisciplinary research could advance our understanding in belowground ecological niche functions and their role in forest ecohydrology and productivity.

  4. Recombination and selection in the major histocompatibility complex of the endangered forest musk deer (Moschus berezovskii).

    Science.gov (United States)

    Cai, Ruibo; Shafer, Aaron B A; Laguardia, Alice; Lin, Zhenzhen; Liu, Shuqiang; Hu, Defu

    2015-11-25

    The forest musk deer (Moschus berezovskii) is a high elevation species distributed across western China and northern Vietnam. Once abundant, habitat loss and poaching has led to a dramatic decrease in population numbers prompting the IUCN to list the species as endangered. Here, we characterized the genetic diversity of a Major Histocompatibility Complex (MHC) locus and teased apart driving factors shaping its variation. Seven DRB exon 2 alleles were identified among a group of randomly sampled forest musk deer from a captive population in the Sichuan province of China. Compared to other endangered or captive ungulates, forest musk deer have relatively low levels of MHC genetic diversity. Non-synonymous substitutions primarily occurred in the putative peptide-binding region (PBR), with analyses suggesting that recombination and selection has shaped the genetic diversity across the locus. Specifically, inter-allelic recombination generated novel allelic combinations, with evidence for both positive selection acting on the PBR and negative selection on the non-PBR. An improved understanding of functional genetic variability of the MHC will facilitate better design and management of captive breeding programs for this endangered species.

  5. Technical note: Application of geophysical tools for tree root studies in forest ecosystems in complex soils

    Directory of Open Access Journals (Sweden)

    U. Rodríguez-Robles

    2017-11-01

    Full Text Available While semiarid forests frequently colonize rocky substrates, knowledge is scarce on how roots garner resources in these extreme habitats. The Sierra San Miguelito Volcanic Complex in central Mexico exhibits shallow soils and impermeable rhyolitic-rock outcrops, which impede water movement and root placement beyond the soil matrix. However, rock fractures, exfoliated rocks and soil pockets potentially permit downward water percolation and root growth. With ground-penetrating radar (GPR and electrical resistivity tomography (ERT, two geophysical methods advocated by Jayawickreme et al. (2014 to advance root ecology, we advanced in the method development studying root and water distribution in shallow rocky soils and rock fractures in a semiarid forest. We calibrated geophysical images with in situ root measurements, and then extrapolated root distribution over larger areas. Using GPR shielded antennas, we identified both fine and coarse pine and oak roots from 0.6 to 7.5 cm diameter at different depths into either soil or rock fractures. We also detected, trees anchoring their trunks using coarse roots underneath rock outcroppings. With ERT, we tracked monthly changes in humidity at the soil–bedrock interface, which clearly explained spatial root distribution of both tree species. Geophysical methods have enormous potential in elucidating root ecology. More interdisciplinary research could advance our understanding in belowground ecological niche functions and their role in forest ecohydrology and productivity.

  6. Historic Shortleaf Pine (Pinus echinata Mill.) Abundance and Fire Frequency in a Mixed Oak - Pine Forest (MOFEP, Site 8)

    Science.gov (United States)

    Richard P. Guyette; Daniel C. Dey

    1997-01-01

    Historic and present day shortleaf pine (Pinus echinata Mill.) abundance was measured and compared using 84 plots along 16 transects in site 8 of the Missouri Ozark Forest Ecosystem Project. Remnant pine stumps were used to estimate historic pine density and to construct a dendrochronological record of fire frequency. There has been a 66-percent...

  7. Fate of Hexazinone and Picloram After Herbicide Site Preparation in a Cutover Northern Hardwood Forest

    Science.gov (United States)

    D.G. Neary; J.L. Michael; M.J.M. Wells

    1985-01-01

    Herbicides show promise to improve the efficiency and economics of forest stand conversion and regeneration. However, the impacts of herbicides on forest ecosystems and the ultimate fate of these chemicals are not completely understood. A major problem in pine regeneration in northern mixed hardwood forests is competition from fast-growing and easily sprouting species...

  8. Flexibility in nest-site choice and nesting success of Turdus rufiventris (Turdidae) in a montane forest in northwestern argentina

    Science.gov (United States)

    Lomascolo, S.B.; Monmany, A.C.; Malizia, A.; Martin, T.E.

    2010-01-01

    We studied the consequences of nest-site choice on nesting success under differing disturbance levels for the Rufous-bellied Thrush (Turdus rufiventris). We compared nest-site choice and nest success between a disturbed site and an undisturbed site in a montane subtropical forest in northwestern Argentina. We found no overall difference in daily predation rate (DPR) between the disturbed and undisturbed sites. However, DPR of nests on bromeliads was significantly lower at the microhabitat level than on other types of subtrates at the disturbed site. T. rufiventris used bromeliads for nesting more often than expected by chance at the disturbed site. DPR did not differ between substrates at the undisturbed site and T. rufiventris used all substrates according to their availability. Nests had higher predation at the disturbed site when DPR on non-bromeliad substrates was compared between disturbed and undisturbed sites. Nest fate was independent of nest height. Our results suggest T. rufiventris' flexibility in nest-site choice, as reflected by increased use of the safest sites, i.e., bromeliads, in the disturbed site compared to the undisturbed site, may allow this species to survive in an otherwise much riskier habitat. Our results illustrate how microhabitat-scale effects can mediate landscape scale effects. ?? 2010 by the Wilson Ornithological Society.

  9. Simulating the Effects of Fire on Forests in the Russian Far East: Integrating a Fire Danger Model and the FAREAST Forest Growth Model Across a Complex Landscape

    Science.gov (United States)

    Sherman, N. J.; Loboda, T.; Sun, G.; Shugart, H. H.; Csiszar, I.

    2008-12-01

    probability. The output of the model includes biomass estimates for 44 tree species that occur in the RFE, grouped by genus. We compared the model outputs with land cover classifications derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) data and LIDAR-based estimates of biomass across the entire region, and Russian forest inventory records at selected sites. Overall, we find that the FAREAST estimates of forest biomass and general composition are consistent with the observed distribution of forest types.

  10. Final Technical Report: The effects of climate, forest age, and disturbance history on carbon and water processes at AmeriFlux sites across gradients in Pacific Northwest forests

    Energy Technology Data Exchange (ETDEWEB)

    Law, Beverly E. [Oregon State Univ., Corvallis, OR (United States)

    2016-12-03

    Investigate the effects of disturbance and climate variables on processes controlling carbon and water processes at AmeriFlux cluster sites in semi-arid and mesic forests in Oregon. The observations were made at three existing and productive AmeriFlux research sites that represent climate and disturbance gradients as a natural experiment of the influence of climatic and hydrologic variability on carbon sequestration and resulting atmospheric CO2 feedback that includes anomalies during the warm/ dry phase of the Pacific Decadal Oscillation.

  11. Gaseous nitrogen losses from a forest site in the North Tyrolean Limestone Alps.

    Science.gov (United States)

    Härtel, Elisabeth; Zechmeister-Boltenstern, Sophie; Gerzabck, Martin

    2002-01-01

    Microorganisms are responsible for the mineralisation of organic nitrogen in soils. NH4+ can be further oxidised to NO3- during nitrification and NO3- can be reduced to gaseous nitrogen compounds during denitrification. During both processes, nitrous oxide (N2O), which is known as greenhouse gas, can be lost from the ecosystem. The aim of this study was to quantify N2O emissions and the internal microbial N cycle including net N mineralisation and net nitrification in a montane forest ecosystem in the North Tyrolean Limestone Alps during an 18-month measurement period and to estimate the importance of these fluxes in comparison with other components of the N cycle. Gas samples were taken every 2 weeks using the closed chamber method. Additionally, CO2 emission rates were measured to estimate soil respiration activity. Net mineralisation and net nitrification rates were determined by the buried bag method every month. Ion exchange resin bags were used to determine the N availability in the root zone. Mean N2O emission rate was 0.9 kg N ha(-1) a(-1), which corresponds to 5% of the N deposited in the forest ecosystem. The main influencing factors were air and soil temperature and NO3- accumulated on the ion exchange resin bags. In the course of net ammonification, 14 kg NH4+-N ha(-1) were produced per year. About the same amount of NO3--N was formed during nitrification, indicating a rather complete nitrification going on at the site. NO3- concentrations found on the ion exchange resin bags were about 3 times as high as NO3- produced during net nitrification, indicating substantial NO3- immobilisation. The results of this study indicate significant nitrification activities taking place at the Mühleggerköpfl.

  12. Long term measurements of aerosol optical properties at a primary forest site in Amazonia

    Directory of Open Access Journals (Sweden)

    L. V. Rizzo

    2013-03-01

    Full Text Available A long term experiment was conducted in a primary forest area in Amazonia, with continuous in-situ measurements of aerosol optical properties between February 2008 and April 2011, comprising, to our knowledge, the longest database ever in the Amazon Basin. Two major classes of aerosol particles, with significantly different optical properties were identified: coarse mode predominant biogenic aerosols in the wet season (January–June, naturally released by the forest metabolism, and fine mode dominated biomass burning aerosols in the dry season (July–December, transported from regional fires. Dry particle median scattering coefficients at the wavelength of 550 nm increased from 6.3 Mm−1 to 22 Mm−1, whereas absorption at 637 nm increased from 0.5 Mm−1 to 2.8 Mm−1 from wet to dry season. Most of the scattering in the dry season was attributed to the predominance of fine mode (PM2 particles (40–80% of PM10 mass, while the enhanced absorption coefficients are attributed to the presence of light absorbing aerosols from biomass burning. As both scattering and absorption increased in the dry season, the single scattering albedo (SSA did not show a significant seasonal variability, in average 0.86 ± 0.08 at 637 nm for dry aerosols. Measured particle optical properties were used to estimate the aerosol forcing efficiency at the top of the atmosphere. Results indicate that in this primary forest site the radiative balance was dominated by the cloud cover, particularly in the wet season. Due to the high cloud fractions, the aerosol forcing efficiency absolute values were below −3.5 W m−2 in 70% of the wet season days and in 46% of the dry season days. Besides the seasonal variation, the influence of out-of-Basin aerosol sources was observed occasionally. Periods of influence of the Manaus urban plume were detected, characterized by a consistent increase on particle scattering (factor 2.5 and absorption coefficients (factor 5. Episodes of

  13. Forest Site Classification in the Southern Andean Region of Ecuador: A Case Study of Pine Plantations to Collect a Base of Soil Attributes

    Directory of Open Access Journals (Sweden)

    Pablo Quichimbo

    2017-12-01

    Full Text Available Forest site classification adapted to the respective site conditions is one prerequisite for sustainable silviculture. This work aims to initiate the forest site classification for pine plantations in the southern Andean region of Ecuador. Forest productivity, estimated by the dominant height of 20-year-old trees (DH20, was related to data from climate, topography, and soil using 23 plots installed in pine plantations in the province of Loja. Forest site productivity was classified as: low (class C: 13.4 m, middle (class B: 16.6 m, and high (Class A: 22.3 m. Strong determinants to differentiate the forest site classes were: the short to medium term available Ca and K stocks (organic layer + mineral soil standardized to a depth of 60 cm, soil acidity, the C:N ratio, clay and sand content, forest floor thickness, altitude, and slope. The lowest forest productivity (Class C is mainly associated with the lowest short to medium term available K and Ca stocks. Whereas, in site classes with the highest forest productivity, pines could benefit from a more active microbial community releasing N and P, since the soil pH was about 1 unit less acidic. This is supported by the lowest forest floor thickness and the narrowest C:N ratio.

  14. Evapotranspiration (ET) data at Dead River forested wetland site, Hillsborough County, Florida, December 2009 - February 2016

    Science.gov (United States)

    Swancar, Amy

    2016-01-01

    The data set consists of evapotranspiration measurements made at the USGS Dead River forested wetland climate station beginning November 21, 2009 and ending February 29, 2016. Annual ET rates corrected to a near-surface energy-budget varied from 1448 mm (2012) to 1614 mm (2010). The eddy-covariance method was used, with high-frequency sensors installed above the forest canopy to measure sensible and latent heat fluxes. Ancillary meteorological data are also included in the data set: net radiation, soil temperature and moisture, air temperature, relative humidity, wind speed and direction, rainfall, and ground-water levels. Data were collected at 30-minute resolution, with evapotranspiration corrected to the near-surface energy-budget at a daily timescale. The study was conducted at an undeveloped mixed hardwood swamp within Dead River Wilderness Park, located at the end of Dead River Rd., west of U.S. Highway 301, 27 km northeast of Tampa in Hillsborough County, Florida (latitude 28 07’ 43” N  longitude 82 15’ 44” W, Section 13, Township 27S, Range 20E). Study instruments were installed in November 2009. The 46-m instrument tower was located about 90 m northeast of the final pullout before the parking area, which is 2.6 km from the park entrance gate on Dead River Rd.  The station is within the Hillsborough River floodplain, and is inundated at high river stages (Lewelling, 2004).  The site is classified as a freshwater palustrine forested broad-leaf deciduous wetland that is seasonally flooded (U.S. Fish and Wildlife Service, 2010).  Dominant tree species are cabbage palm (Sabal palmetto), red maple (Acer rubrum), sweet-gum (Liquidambar styraciflua), live oak (Quercus virginiana), elm (Ulmus americana), with occasional slash pine, magnolia, and hickory.  Canopy height is 20-24 m.  The site is located near the middle of the floodplain at least 1 km away from different land cover types in all directions.  The floodplain extends farther to the

  15. Nano Random Forests to mine protein complexes and their relationships in quantitative proteomics data.

    Science.gov (United States)

    Montaño-Gutierrez, Luis F; Ohta, Shinya; Kustatscher, Georg; Earnshaw, William C; Rappsilber, Juri

    2017-03-01

    Ever-increasing numbers of quantitative proteomics data sets constitute an underexploited resource for investigating protein function. Multiprotein complexes often follow consistent trends in these experiments, which could provide insights about their biology. Yet, as more experiments are considered, a complex's signature may become conditional and less identifiable. Previously we successfully distinguished the general proteomic signature of genuine chromosomal proteins from hitchhikers using the Random Forests (RF) machine learning algorithm. Here we test whether small protein complexes can define distinguishable signatures of their own, despite the assumption that machine learning needs large training sets. We show, with simulated and real proteomics data, that RF can detect small protein complexes and relationships between them. We identify several complexes in quantitative proteomics results of wild-type and knockout mitotic chromosomes. Other proteins covary strongly with these complexes, suggesting novel functional links for later study. Integrating the RF analysis for several complexes reveals known interdependences among kinetochore subunits and a novel dependence between the inner kinetochore and condensin. Ribosomal proteins, although identified, remained independent of kinetochore subcomplexes. Together these results show that this complex-oriented RF (NanoRF) approach can integrate proteomics data to uncover subtle protein relationships. Our NanoRF pipeline is available online. © 2017 Montaño-Gutierrez et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  16. iRPIS-PseNNC: identifying RNA-protein interaction sites by incorporating the position-specific dinucleotide propensity into ensemble random forest approach

    Science.gov (United States)

    Li, Long; Chen, Guojin; Jin, Tingdu

    2017-06-01

    As the pile of RNA-Protein complexes sequences mounted, in order to overcome time-consuming problem of the traditional identify RNA-Protein interaction sites (RPIS) method, it is urgent need develop intelligent recognition approach for quickly and reliable recognition of the RNA-Protein interaction sites (RPIS). To settle the question, we developed a new method named iRPIS-PseNNC, in which each sample is a nineteen nucleotides segment that for positive the centre of the segments is RPIS and for negative the segments centre is non-RPIS, and the sample was obtained by sliding window. The RNA sample was formulated by combining the dipeptide position-specific propensity into random forest approach, and by using the random sampling to balance the training dataset. According the voting system, we combine eleven random forest together to construct an ensemble classifier. It is shown that via the rigorous cross validations that the new predictor “iRPIS-PseNNC” achieved very high percentage of accuracy than any other existing algorithms in this field, indicating that the iRPIS-PseNNC predictor will be an effective tool for prediction RNA-Protein interaction sites.

  17. Constraining ecosystem model with adaptive Metropolis algorithm using boreal forest site eddy covariance measurements

    Science.gov (United States)

    Mäkelä, Jarmo; Susiluoto, Jouni; Markkanen, Tiina; Aurela, Mika; Järvinen, Heikki; Mammarella, Ivan; Hagemann, Stefan; Aalto, Tuula

    2016-12-01

    We examined parameter optimisation in the JSBACH (Kaminski et al., 2013; Knorr and Kattge, 2005; Reick et al., 2013) ecosystem model, applied to two boreal forest sites (Hyytiälä and Sodankylä) in Finland. We identified and tested key parameters in soil hydrology and forest water and carbon-exchange-related formulations, and optimised them using the adaptive Metropolis (AM) algorithm for Hyytiälä with a 5-year calibration period (2000-2004) followed by a 4-year validation period (2005-2008). Sodankylä acted as an independent validation site, where optimisations were not made. The tuning provided estimates for full distribution of possible parameters, along with information about correlation, sensitivity and identifiability. Some parameters were correlated with each other due to a phenomenological connection between carbon uptake and water stress or other connections due to the set-up of the model formulations. The latter holds especially for vegetation phenology parameters. The least identifiable parameters include phenology parameters, parameters connecting relative humidity and soil dryness, and the field capacity of the skin reservoir. These soil parameters were masked by the large contribution from vegetation transpiration. In addition to leaf area index and the maximum carboxylation rate, the most effective parameters adjusting the gross primary production (GPP) and evapotranspiration (ET) fluxes in seasonal tuning were related to soil wilting point, drainage and moisture stress imposed on vegetation. For daily and half-hourly tunings the most important parameters were the ratio of leaf internal CO2 concentration to external CO2 and the parameter connecting relative humidity and soil dryness. Effectively the seasonal tuning transferred water from soil moisture into ET, and daily and half-hourly tunings reversed this process. The seasonal tuning improved the month-to-month development of GPP and ET, and produced the most stable estimates of water use

  18. Comparison of Aerial and Terrestrial Remote Sensing Techniques for Quantifying Forest Canopy Structural Complexity and Estimating Net Primary Productivity

    Science.gov (United States)

    Fahey, R. T.; Tallant, J.; Gough, C. M.; Hardiman, B. S.; Atkins, J.; Scheuermann, C. M.

    2016-12-01

    Canopy structure can be an important driver of forest ecosystem functioning - affecting factors such as radiative transfer and light use efficiency, and consequently net primary production (NPP). Both above- (aerial) and below-canopy (terrestrial) remote sensing techniques are used to assess canopy structure and each has advantages and disadvantages. Aerial techniques can cover large geographical areas and provide detailed information on canopy surface and canopy height, but are generally unable to quantitatively assess interior canopy structure. Terrestrial methods provide high resolution information on interior canopy structure and can be cost-effectively repeated, but are limited to very small footprints. Although these methods are often utilized to derive similar metrics (e.g., rugosity, LAI) and to address equivalent ecological questions and relationships (e.g., link between LAI and productivity), rarely are inter-comparisons made between techniques. Our objective is to compare methods for deriving canopy structural complexity (CSC) metrics and to assess the capacity of commonly available aerial remote sensing products (and combinations) to match terrestrially-sensed data. We also assess the potential to combine CSC metrics with image-based analysis to predict plot-based NPP measurements in forests of different ages and different levels of complexity. We use combinations of data from drone-based imagery (RGB, NIR, Red Edge), aerial LiDAR (commonly available medium-density leaf-off), terrestrial scanning LiDAR, portable canopy LiDAR, and a permanent plot network - all collected at the University of Michigan Biological Station. Our results will highlight the potential for deriving functionally meaningful CSC metrics from aerial imagery, LiDAR, and combinations of data sources. We will also present results of modeling focused on predicting plot-level NPP from combinations of image-based vegetation indices (e.g., NDVI, EVI) with LiDAR- or image-derived metrics of

  19. Energy Efficiency, Water Efficiency, and Renewable Energy Site Assessment: San Juan National Forest - Dolores Ranger District, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Kandt, Alicen J. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Kiatreungwattana, Kosol [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2018-01-26

    This report summarizes the results from an energy efficiency, water efficiency, and renewable energy site assessment of the Dolores Ranger District in the San Juan National Forest in Colorado. A team led by the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) conducted the assessment with United States Forest Service (USFS) personnel on August 16-17, 2016, as part of ongoing efforts by USFS to reduce energy and water use and implement renewable energy technologies. The assessment is approximately an American Society of Heating, Refrigerating, and Air-Conditioning Engineers Level 2 audit and meets Energy Independence and Security Act requirements.

  20. Influence of Anthropogenic Disturbances on Stand Structural Complexity in Andean Temperate Forests: Implications for Managing Key Habitat for Biodiversity

    Science.gov (United States)

    2017-01-01

    Forest attributes and their abundances define the stand structural complexity available as habitat for faunal biodiversity; however, intensive anthropogenic disturbances have the potential to degrade and simplify forest stands. In this paper we develop an index of stand structural complexity and show how anthropogenic disturbances, namely fire, logging, livestock, and their combined presence, affect stand structural complexity in a southern Global Biodiversity Hotspot. From 2011 to 2013, we measured forest structural attributes as well as the presence of anthropogenic disturbances in 505 plots in the Andean zone of the La Araucanía Region, Chile. In each plot, understory density, coarse woody debris, number of snags, tree diameter at breast height, and litter depth were measured, along with signs of the presence of anthropogenic disturbances. Ninety-five percent of the plots showed signs of anthropogenic disturbance (N = 475), with the combined presence of fire, logging, and livestock being the most common disturbance (N = 222; 44% of plots). The lowest values for the index were measured in plots combining fire, logging, and livestock. Undisturbed plots and plots with the presence of relatively old fires (> 70 years) showed the highest values for the index of stand structural complexity. Our results suggest that secondary forests forests should be managed to retain structural attributes, including understory density (7.2 ± 2.5 # contacts), volume of CWD (22.4 ± 25.8 m3/ha), snag density (94.4 ± 71.0 stems/ha), stand basal area (61.2 ± 31.4 m2/ha), and litter depth (7.5 ± 2.7 cm). Achieving these values will increase forest structural complexity, likely benefiting a range of faunal species in South American temperate forests. PMID:28068349

  1. Tethered balloon measurements of biogenic volatile organic compounds at a Boreal forest site

    Directory of Open Access Journals (Sweden)

    C. Spirig

    2004-01-01

    Full Text Available Measurements of biogenic volatile organic compounds (VOCs were performed at Hyytiälä, a Boreal forest site in Southern Finland as part of the OSOA (origin and formation of secondary organic aerosol project in August 2001. At this site, frequent formation of new particles has been observed and the role of biogenic VOCs in this process is still unclear. Tethered balloons served as platforms to collect VOC samples within the planetary boundary layer at heights up to 1.2 km above ground during daytime. Mean mixed layer concentrations of total monoterpenes varied between 10 and 170 pptv, with a-pinene, limonene and D3-carene as major compounds, isoprene was detected at levels of 2-35 pptv. A mixed layer gradient technique and a budget approach are applied to derive surface fluxes representative for areas of tens to hundreds of square kilometres. Effects of spatial heterogeneity in surface emissions are examined with a footprint analysis. Depending on the source area considered, mean afternoon emissions of the sum of terpenes range between 180 and 300 mg m-2 h-1 for the period of 2-12 August 2001. Surface fluxes close to Hyytiälä were higher than the regional average, and agree well with mean emissions predicted by a biogenic VOC emission model. Total rates of monoterpene oxidation were calculated with a photochemical model. The rates did not correlate with the occurrence of new particle formation, but the ozone pathway was of more importance on days with particle formation. Condensable vapour production from the oxidation of monoterpenes throughout the mixed layer can only account for a fraction of the increase in aerosol mass observed at the surface.

  2. Influence of air mass origin on aerosol properties at a remote Michigan forest site

    Science.gov (United States)

    VanReken, T. M.; Mwaniki, G. R.; Wallace, H. W.; Pressley, S. N.; Erickson, M. H.; Jobson, B. T.; Lamb, B. K.

    2015-04-01

    The northern Great Lakes region of North America is a large, relatively pristine area. To date, there has only been limited study of the atmospheric aerosol in this region. During summer 2009, a detailed characterization of the atmospheric aerosol was conducted at the University of Michigan Biological Station (UMBS) as part of the Community Atmosphere-Biosphere Interactions Experiment (CABINEX). Measurements included particle size distribution, water-soluble composition, and CCN activity. Aerosol properties were strongly dependent on the origin of the air masses reaching the site. For ∼60% of the study period, air was transported from sparsely populated regions to the northwest. During these times aerosol loadings were low, with mean number and volume concentrations of 1630 cm-3 and 1.91 μm3 cm-3, respectively. The aerosol during clean periods was dominated by organics, and exhibited low hygroscopicities (mean κ = 0.18 at s = 0.3%). When air was from more populated regions to the east and south (∼29% of the time), aerosol properties reflected a stronger anthropogenic influence, with 85% greater particle number concentrations, 2.5 times greater aerosol volume, six times more sulfate mass, and increased hygroscopicity (mean k = 0.24 at s = 0.3%). These trends are have the potential to influence forest-atmosphere interactions and should be targeted for future study.

  3. Long-term deer exclusion has complex effects on a suburban forest understory

    Science.gov (United States)

    Faison, Edward K.; Foster, David R.; DeStefano, Stephen

    2016-01-01

    Herbivory by deer is one of the leading biotic disturbances on forest understories (i.e., herbs, small shrubs, and small tree seedlings). A large body of research has reported declines in height, abundance, and reproductive capacity of forbs and woody plants coupled with increases in abundance of graminoids, ferns, and exotic species due to deer herbivory. Less clear is the extent to which (and the direction in which) deer alter herbaceous layer diversity, where much of the plant diversity in a forest occurs. We examined the effect of 15 y of deer exclusion on the understory of a suburban hardwood forest in Connecticut exposed to decades of intensive herbivory by white-tailed deer (Odocoileus virginianus). We compared species richness (at subplot and plot scale), individual species and life form group abundance (% cover), and community composition between grazed and exclosure plots, as well as between mesic and wet soil blocks. Forb cover was more than twice as abundant in exclosure as in grazed plots, whereas sedge (Carex spp.) cover was 28 times more abundant, and exotic species cover generally higher in grazed than in exclosure plots. Native and exotic species richness were both higher in grazed than exclosure plots at the subplot scale, and native herbaceous richness was higher in grazed plots at both spatial scales. In contrast, native shrub richness increased with deer exclusion at the plot scale. Our results suggest that deer exclusion had contrasting effects on species richness, depending on plant life form, but that overall richness of both exotic and native plants declined with deer exclusion. In addition, site heterogeneity remained an important driver of vegetation dynamics even in the midst of high deer densities.

  4. Organic complexation of copper in throughfall and open field bulk deposition: Influence of the tree canopy of Mediterranean forest ecosystems.

    Science.gov (United States)

    Karavoltsos, Sotirios; Fotiadis, Fotios; Michopoulos, Panagiotis; Sakellari, Aikaterini; Plavšić, Marta; Bourletsikas, Athanassios; Kaoukis, Kostas; Thomaidis, Nikolaos S; Dassenakis, Manos; Scoullos, Michael

    2017-01-01

    The complexing capacity for Cu ions (LT) and the apparent stability constant values (logKapp) were measured in throughfall (TF) and open field bulk deposition (BD), at two Mediterranean forest ecosystems of western Greece. LT was measured for the first time in the TF of natural forests. Concentrations of LT were three-to-four-fold higher in TF (mean ± st.dev: 2014 ± 769 nM for Varetada and 1565 ± 595 nM for Karpenissi) compared to those in BD (531 ± 517 nM and 468 ± 321 nM, respectively). In all TF and BD samples, LT concentrations were significantly higher than the corresponding total Cu concentrations, indicating that Cu was fully complexed. The LT/TOC ratios in TF were found comparable between the two study sites (235 ± 149 nM mg-1 C for Varetada and 256 ± 233 nM mg-1 C for Karpenissi) and with those of BD (226 ± 257 and 163 ± 163 nM mg-1 C, respectively). The determined mean logKapp values were almost identical in TF (6.8 ± 0.7 at Varetada; 6.8 ± 0.6 at Karpenissi) and BD (6.5 ± 0.6 at Varetada; 6.8 ± 0.3 at Karpenissi), pointing to the fact that regardless of the enrichment of TF in ligands (LT(TF) > LT(BD)) the type of binding sites remain the same. The logKapp values which were obtained herewith are similar to those obtained for humic-like substances (HULIS), indicating them as the most widespread type of ligands in BD and TF. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. LBA-ECO TG-02 Biogenic VOC Emissions from Brazilian Amazon Forest and Pasture Sites

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set reports concentrations of biogenic volatile organic compounds (BVOCs) collected from tethered balloon-sampling platforms above selected forest and...

  6. Effect of Disturbance Regimes on Spatial Patterns of Tree Species in Three Sites in a Tropical Evergreen Forest in Vietnam

    Directory of Open Access Journals (Sweden)

    Do Thi Ngoc Le

    2016-01-01

    Full Text Available The effects of disturbance regimes on the spatial patterns of the five most abundant species were investigated in three sites in a tropical forest at Xuan Nha Nature Reserve, Vietnam. Three permanent one-ha plots were established in undisturbed forest (UDF, lightly disturbed forest (LDF, and highly disturbed forest (HDF. All trees ≥5 cm DBH were measured in twenty-five 20 m × 20 m subplots. A total of 57 tree species belonging to 26 families were identified in the three forest types. The UDF had the highest basal area (30 m2 ha−1, followed by the LDF (17 m2 ha−1 and the HDF (13.0 m2 ha−1. The UDF also had the highest tree density (751 individuals ha−1 while the HDF held the lowest (478 individuals ha−1. Across all species, there were 417 “juveniles,” 267 “subadults,” and 67 “adults” in the UDF, while 274 “juveniles,” 230 “subadults,” and 36 “adults” were recorded in the LDF. 238 “juveniles,” 227 “subadults,” and 13 “adults” were obtained in the HDF. The univariate and bivariate data with pair- and mark-correlation functions of intra- and interspecific interactions of the five most abundant species changed in the three forest types. Most species indicated clumping or regular distributions at small scale, but a high ratio of negative interspecific small-scale associations was recorded in both the LDF and HDF sites. These were, however, rare in the UDF.

  7. Validation of MODIS and GEOV1 fPAR Products in a Boreal Forest Site in Finland

    Directory of Open Access Journals (Sweden)

    Titta Majasalmi

    2015-01-01

    Full Text Available Remote sensing of the fraction of absorbed Photosynthetically Active Radiation (fPAR has become a timely option to monitor forest productivity. However, only a few studies have had ground reference fPAR datasets containing both forest canopy and understory fPAR from boreal forests for the validation of satellite products. The aim of this paper was to assess the performance of two currently available satellite-based fPAR products: MODIS fPAR (MOD15A2, C5 and GEOV1 fPAR (g2_BIOPAR_FAPAR, as well as an NDVI-fPAR relationship applied to the MODIS surface reflectance product and a Landsat 8 image, in a boreal forest site in Finland. Our study area covered 16 km2 and field data were collected from 307 forest plots. For all plots, we obtained both forest canopy fPAR and understory fPAR. The ground reference total fPAR agreed better with GEOV1 fPAR than with MODIS fPAR, which showed much more temporal variation during the peak-season than GEOV1 fPAR. At the chosen intercomparison date in peak growing season, MODIS NDVI based fPAR estimates were similar to GEOV1 fPAR, and produced on average 0.01 fPAR units smaller fPAR estimates than ground reference total fPAR. MODIS fPAR and Landsat 8 NDVI based fPAR estimates were similar to forest canopy fPAR.

  8. Implementation and complexity of the watershed-from-markers algorithm computed as a minimal cost forest

    CERN Document Server

    Felkel, P; Wegenkittl, R; Felkel, Petr; Bruckwschwaiger, Mario; Wegenkittl, Rainer

    2001-01-01

    The watershed algorithm belongs to classical algorithms in mathematical morphology. Lotufo et al. published a principle of the watershed computation by means of an iterative forest transform (IFT), which computes a shortest path forest from given markers. The algorithm itself was described for a 2D case (image) without a detailed discussion of its computation and memory demands for real datasets. As IFT cleverly solves the problem of plateaus and as it gives precise results when thin objects have to be segmented, it is obvious to use this algorithm for 3D datasets taking in mind the minimizing of a higher memory consumption for the 3D case without loosing low asymptotical time complexity of O(m+C) (and also the real computation speed). The main goal of this paper is an implementation of the IFT algorithm with a priority queue with buckets and careful tuning of this implementation to reach as minimal memory consumption as possible. The paper presents five possible modifications and methods of implementation of...

  9. Using Florida Keys Reference Sites As a Standard for Restoration of Forest Structure in Everglades Tree Islands

    Directory of Open Access Journals (Sweden)

    Michael S. Ross

    2010-01-01

    Full Text Available In south Florida, tropical hardwood forests (hammocks occur in Everglades tree islands and as more extensive forests in coastal settings in the nearby Florida Keys. Keys hammocks have been less disturbed by humans, and many qualify as “old-growth,” while Everglades hammocks have received much heavier use. With improvement of tree island condition an important element in Everglades restoration efforts, we examined stand structure in 23 Keys hammocks and 69 Everglades tree islands. Based on Stand Density Index and tree diameter distributions, many Everglades hammocks were characterized by low stocking and under-representation in the smaller size classes. In contrast, most Keys forests had the dense canopies and open understories usually associated with old-growth hardwood hammocks. Subject to the same caveats that apply to off-site references elsewhere, structural information from mature Keys hammocks can be helpful in planning and implementing forest restoration in Everglades tree islands. In many of these islands, such restoration might involve supplementing tree stocking by planting native trees to produce more complete site utilization and a more open understory.

  10. Fire detection system using random forest classification for image sequences of complex background

    Science.gov (United States)

    Kim, Onecue; Kang, Dong-Joong

    2013-06-01

    We present a fire alarm system based on image processing that detects fire accidents in various environments. To reduce false alarms that frequently appeared in earlier systems, we combined image features including color, motion, and blinking information. We specifically define the color conditions of fires in hue, saturation and value, and RGB color space. Fire features are represented as intensity variation, color mean and variance, motion, and image differences. Moreover, blinking fire features are modeled by using crossing patches. We propose an algorithm that classifies patches into fire or nonfire areas by using random forest supervised learning. We design an embedded surveillance device made with acrylonitrile butadiene styrene housing for stable fire detection in outdoor environments. The experimental results show that our algorithm works robustly in complex environments and is able to detect fires in real time.

  11. Predicting forest road surface erosion and storm runoff from high-elevation sites

    Science.gov (United States)

    J. M. Grace III

    2017-01-01

    Forest roads are a concern in management because they represent areas of elevated risks associated with soil erosion and storm runoff connectivity to stream systems. Storm runoff emanating from forest roads and their connectivity to downslope resources can be influenced by a myriad of factors, including storm characteristics, management practices, and the interaction...

  12. Opportunities and uses of biochar on forest sites in North America [Chapter 15

    Science.gov (United States)

    Deborah S. Page-Dumroese; Mark D. Coleman; Sean C. Thomas

    2017-01-01

    Biochar may be useful for restoring or revitalizing degraded forest soils and help with carbon sequestration, nutrient leaching losses, and reducing greenhouse gas emissions. However, biochar is not currently widely used on forested lands across North America. This chapter provides an overview of several biochar experiments conducted in North America and discusses the...

  13. Site factor variations and responses in temporary forest types in northern Idaho

    Science.gov (United States)

    J. A. Larsen

    1940-01-01

    The object of the study was to analyze and evaluate the environmental factors which govern the progressional stages of the secondary forest succession in northern Idaho. \\When this study began much uncertainty existed regarding the distribution of trees and forest types in relation to temperature, precipitation, and evaporation and regarding their soil moisture and...

  14. Using forest knowledge: how silviculture can benefit from ecological knowledge systems about beargrass harvesting sites

    Science.gov (United States)

    S. Hummel; Frank Lake; A. Watts

    2015-01-01

    Sustaining the health, diversity, and productivity of national forests and grasslands is the mission of the U.S. Department of Agriculture (USDA) Forest Service. Yet managing these lands is challenging because people hold different expectations for them. Public uses can include: • Recreation (scenery, trails, bicycle and snowmobile routes)...

  15. Ionic balances of forest soils reciprocally transplanted among sites with varying pollution inputs.

    NARCIS (Netherlands)

    Raubuch, M.; Beese, F.; Bolger, T.; Anderson, J.M.E.; Berg, M.P.; Couteaux, M.-M.; Henderson, R.; Ineson, P.; McCarthy, F.; Palka, L.; Splatt, P.; Verhoef, H.A.; Willison, T.

    1998-01-01

    Forest ecosystems are currently being exposed to changes in chemical inputs and it is suggested that physical climate is also changing. A novel approach has been used to study the effects of ionic inputs and climatic conditions on forest soils by reciprocally exchanging lysimeters containing

  16. Public preferences for future conditions in disturbed and undisturbed northern forest sites

    Science.gov (United States)

    Terry C. Daniel

    2006-01-01

    This study presented computer visualizations (pictures) of projected changes over an 80-year period to conditions in a northern forest that had been hit by a major blowdown. Study participants included local residents and forest visitors who were asked to choose between visualizations of projected outcome scenarios for 10 pairs of treatment versus no-treatment options...

  17. Public Preferences Across Europe for Different Forest Stand Types as Sites for Recreation

    Directory of Open Access Journals (Sweden)

    David M. Edwards

    2012-03-01

    Full Text Available A Delphi survey involving experts in forest preference research was carried out to derive scores for the recreational value of 240 forest stand types across Europe. The survey was organized around four regional panels: Great Britain, Nordic Region, Central Europe, and Iberia. In each region, 60 forest stand types were defined according to five forest management alternatives (FMAs on a continuum of management intensity, four phases of development (establishment, young, medium, and adult, and three tree species types (conifer, broadleaved, and mixed stands of conifer and broadleaved. The resulting scores were examined using conjoint analysis to determine the relative importance of the three structural attributes (FMA, phase of development, and tree species type, and each level or component of the attributes. The findings quantify the extent to which forest visitors prefer a degree of management to unmanaged forest nature reserves across the four regions. Phase of development was shown to make the highest contribution to the recreational value of forests while the contribution of tree species type was shown to be relatively unimportant. While the results are indicative, they provide evidence to support long-term retention and low-impact silviculture in forests where recreation is a primary objective of management.

  18. Site-specific critical acid load estimates for forest soils in the Osborn Creek watershed, Michigan

    Science.gov (United States)

    Trevor Hobbs; Jason Lynch; Randy. Kolka

    2017-01-01

    Anthropogenic acid deposition has the potential to accelerate leaching of soil cations, and in turn, deplete nutrients essential to forest vegetation. The critical load concept, employing a simple mass balance (SMB) approach, is often used to model this process. In an evaluation under the U.S. Forest Service Watershed Condition Framework program, soils in all 6th level...

  19. Wind Resource Assessment Campaign with Lidars and Met Mast in Large and Complex Sites

    Science.gov (United States)

    Boquet, M.; Thobois, L.

    2012-04-01

    Wind farm development in complex sites raise a long list of challenges to keep the cost of produced power as low as possible. Among these challenges is the ability to accurately assess the wind resource. Because wind flow is more difficult to predict at hub height and over the entire site, and because met mast can be difficult to erect on such complex sites, technologies like lidar remote sensors can be an advantageous wind measurement alternative. In this presentation, we propose to show the carry out of a wind resource assessment on a complex area. Lidar uncertainty on this specific site is analyzed as well as its impact on the global assessment of the energy resource for the wind farm project. We show how lidar measurements are combined with mast measurement to reduce the uncertainty of wind resource assessment. Based on the results of this concrete business case, we conclude on the relevance of including lidar remote sensors in a traditional wind resource assessment campaign in a complex site.

  20. MODIS snow cover mapping accuracy in a small mountain catchment – comparison between open and forest sites

    Directory of Open Access Journals (Sweden)

    G. Blöschl

    2012-07-01

    Full Text Available Numerous global and regional validation studies have examined MODIS snow mapping accuracy by using measurements at climate stations, which are mainly at open sites. MODIS accuracy in alpine and forested regions is, however, still not well understood. The main objective of this study is to evaluate MODIS (MOD10A1 and MYD10A1 snow cover products in a small experimental catchment by using extensive snow course measurements at open and forest sites. The MODIS accuracy is tested in the Jalovecky creek catchment (northern Slovakia in the period 2000–2011. The results show that the combined Terra and Aqua images enable snow mapping at an overall accuracy of 91.5%. The accuracies at forested, open and mixed land uses at the Červenec sites are 92.7%, 98.3% and 81.8%, respectively. The use of a 2-day temporal filter enables a significant reduction in the number of days with cloud coverage and an increase in overall snow mapping accuracy. In total, the 2-day temporal filter decreases the number of cloudy days from 61% to 26% and increases the snow mapping accuracy to 94%. The results indicate three possible factors leading to misclassification of snow as land: patchy snow cover, limited MODIS geolocation accuracy and mapping algorithm errors. Out of a total of 27 misclassification cases, patchy snow cover, geolocation issues and mapping errors occur in 12, 12 and 3 cases, respectively.

  1. Observation and Analysis of Particle Nucleation at a Forest Site in Southeastern US

    Directory of Open Access Journals (Sweden)

    Viney Aneja

    2013-04-01

    Full Text Available This study examines the characteristics of new particle formation at a forest site in southeastern US. Particle size distributions above a Loblolly pine plantation were measured between November 2005 and September 2007 and analyzed by event type and frequency, as well as in relation to meteorological and atmospheric chemical conditions. Nucleation events occurred on 69% of classifiable observation days. Nucleation frequency was highest in spring. The highest daily nucleation (class A and B events frequency (81% was observed in April. The average total particle number concentration on nucleation days was 8,684 cm−3 (10 < Dp < 250 nm and 3,991 cm−3 (10 < Dp < 25 nm with a mode diameter of 28 nm with corresponding values on non-nucleation days of 2,143 cm−3, 655 cm−3, and 44.5 nm, respectively. The annual average growth rate during nucleation events was 2.7 ± 0.3 nm·h−1. Higher growth rates were observed during summer months with highest rates observed in May (5.0 ± 3.6 nm·h−1. Winter months were associated with lower growth rates, the lowest occurring in February (1.2 ± 2.2 nm·h−1. Consistent with other studies, nucleation events were more likely to occur on days with higher radiative flux and lower relative humidity compared to non-nucleation days. The daily minimum in the condensation sink, which typically occurred 2 to 3 h after sunrise, was a good indicator of the timing of nucleation onset. The intensity of the event, indicated by the total particle number concentration, was well correlated with photo-synthetically active radiation, used here as a surrogate for total global radiation, and relative humidity. Even though the role of biogenic VOC in the initial nuclei formation is not understood from this study, the relationships with chemical precursors and secondary aerosol products associated with nucleation, coupled with diurnal boundary layer dynamics and seasonal meteorological patterns, suggest that H2SO4 and biogenic

  2. Modeling dynamics of (137)Cs in forest surface environments: Application to a contaminated forest site near Fukushima and assessment of potential impacts of soil organic matter interactions.

    Science.gov (United States)

    Ota, Masakazu; Nagai, Haruyasu; Koarashi, Jun

    2016-05-01

    A process-based model for (137)Cs transfer in forest surface environments was developed to assess the dynamic behavior of Fukushima-derived (137)Cs in a Japanese forest. The model simulation successfully reproduced the observed data from 3year migration of (137)Cs in the organic and mineral soil layers at a contaminated forest near Fukushima. The migration of (137)Cs from the organic layer to the mineral soil was explained by the direct deposition pattern on the forest floor and the turnover of litter materials in the organic layer under certain ecological conditions. Long-term predictions indicated that more than 90% of the deposited (137)Cs would remain within the top 5cm of the soil for up to 30years after the accident, suggesting that the forest acts as an effective long-term reservoir of (137)Cs with limited transfer via the groundwater pathway. The model was also used to explore the potential impacts of soil organic matter (SOM) interactions on the mobility and bioavailability of (137)Cs in the soil-plant system. The simulation results for hypothetical organic soils with modified parameters of (137)Cs turnover revealed that the SOM-induced reduction of (137)Cs adsorption elevates the fraction of dissolved (137)Cs in the soil solution, thereby increasing the soil-to-plant transfer of (137)Cs without substantially altering the fractional distribution of (137)Cs in the soil. Slower fixation of (137)Cs on the flayed edge site of clay minerals and enhanced mobilization of the clay-fixed (137)Cs in organic-rich soils also appeared to elevate the soil-to-plant transfer of (137)Cs by increasing the fraction of the soil-adsorbed (exchangeable) (137)Cs. A substantial proportion (approximate 30%-60%) of (137)Cs in these organic-rich soils was transferred to layers deeper than 5cm decades later. These results suggested that SOM influences the behavior of (137)Cs in forests over a prolonged period through alterations of adsorption and fixation in the soil. Copyright

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

    Energy Technology Data Exchange (ETDEWEB)

    Anderson-Teixeira, Kristina J. [Smithsonian Tropical Research Inst. (STRI), Panama (Panama). Center for Tropical Forest Science. Forest Global Earth Observatory; Smithsonian Conservation Biology Inst. (SCBI), Front Royal, VA (United States). National Zoological Park. Conservation Ecology Center; Davies, Stuart J. [Smithsonian Tropical Research Inst. (STRI), Panama (Panama). Center for Tropical Forest Science. Forest Global Earth Observatory; National Museum of Natural History, Washington, DC (United States). Dept. of Botany; Bennett, Amy C. [Smithsonian Conservation Biology Inst. (SCBI), Front Royal, VA (United States). National Zoological Park. Conservation Ecology Center; Gonzalez-Akre, Erika B. [Smithsonian Conservation Biology Inst. (SCBI), Front Royal, VA (United States). National Zoological Park. Conservation Ecology Center; Muller-Landau, Helene C. [Smithsonian Tropical Research Inst. (STRI), Panama (Panama). Center for Tropical Forest Science. Forest Global Earth Observatory; Joseph Wright, S. [Smithsonian Tropical Research Inst. (STRI), Panama (Panama). Center for Tropical Forest Science. Forest Global Earth Observatory; Abu Salim, Kamariah [Univ. of Brunei Darussalam, Bandar Seri Begawan (Brunei). Faculty of Science. Environmental and Life Sciences; Almeyda Zambrano, Angélica M. [Smithsonian Conservation Biology Inst. (SCBI), Front Royal, VA (United States). National Zoological Park. Conservation Ecology Center; Stanford Univ., CA (United States). Stanford Woods Inst. for the Environment; Univ. of Alabama, Tuscaloosa, AL (United States). Dept. of Geography; Alonso, Alfonso [Smithsonian Conservation Biology Inst., Washington, DC (United States). National Zoological Park. Center for Conservation Education and Sustainability; Baltzer, Jennifer L. [Wilfrid Laurier Univ., Waterloo, ON (Canada). Dept. of Biology; Basset, Yves [Smithsonian Tropical Research Inst. (STRI), Panama (Panama). Center for Tropical Forest Science. Forest Global Earth Observatory; Bourg, Norman A. [Smithsonian Conservation Biology Inst. (SCBI), Front Royal, VA (United States). National Zoological Park. Conservation Ecology Center; Broadbent, Eben N. [Smithsonian Conservation Biology Inst. (SCBI), Front Royal, VA (United States). National Zoological Park. Conservation Ecology Center; Stanford Univ., CA (United States). Stanford Woods Inst. for the Environment; Univ. of Alabama, Tuscaloosa, AL (United States). Dept. of Geography; Brockelman, Warren Y. [Mahidol Univ., Bangkok (Thailand). Dept. of Biology; Bunyavejchewin, Sarayudh [Dept. of National Parks, Wildlife and Plant Conservation, Bangkok (Thailand). Research Office; Burslem, David F. R. P. [Univ. of Aberdeen (United Kingdom). School of Biological Sciences; Butt, Nathalie [Univ. of Queensland, St. Lucia (Australia). School of Biological Sciences; Univ. of Oxford (United Kingdom). School of Geography and the Environment. Environmental Change Inst.; Cao, Min [Chinese Academy of Sciences (CAS), Kunming (China). Xishuangbanna Tropical Botanical Garden. Key Lab. of Tropical Forest Ecology; Cardenas, Dairon [Sinchi Amazonic Inst. of Scientific Research, Bogota (Colombia); Chuyong, George B. [Univ. of Buea (Cameroon). Dept. of Botany and Plant Physiology; Clay, Keith [Indiana Univ., Bloomington, IN (United States). Dept. of Biology; Cordell, Susan [USDA Forest Service, Hilo, HI (United States). Inst. of Pacific Islands Forestry; Dattaraja, Handanakere S. [Indian Inst. of Science, Bangalore (India). Centre for Ecological Sciences; Deng, Xiaobao [Chinese Academy of Sciences (CAS), Kunming (China). Xishuangbanna Tropical Botanical Garden. Key Lab. of Tropical Forest Ecology; Detto, Matteo [Smithsonian Tropical Research Inst. (STRI), Panama (Panama). Center for Tropical Forest Science. Forest Global Earth Observatory; Du, Xiaojun [Chinese Academy of Sciences (CAS), Beijing (China). Inst. of Botany; Duque, Alvaro [Univ. Nacional de Colombia, Medellin (Colombia). Dept. de Ciencias Forestales; Erikson, David L. [National Museum of Natural History, Washington, DC (United States). Dept. of Botany; Ewango, Corneille E. N. [Okapi Wildlife Reserve, Epulu (Democratic Republic of the Congo). Centre de Formation et de Recherche en Conservation Forestiere (CEFRECOF); Fischer, Gunter A. [Kadoorie Farm and Botanic Garden, Tai Po, Hong Kong (China); Fletcher, Christine [Forest Research Inst. Malaysia (FRIM), Selangor (Malaysia); Foster, Robin B. [The Field Museum, Chicago, IL (United States). Botany Dept.; Giardina, Christian P. [USDA Forest Service, Hilo, HI (United States). Inst. of Pacific Islands Forestry; Gilbert, Gregory S. [Smithsonian Tropical Research Inst. (STRI), Panama (Panama). Center for Tropical Forest Science. Forest Global Earth Observatory; Univ. of California, Santa Cruz, CA (United States). Environmental Studies Dept.; Gunatilleke, Nimal [Univ. of Peradeniya (Sri Lanka). Faculty of Science. Dept. of Botany; Gunatilleke, Savitri [Univ. of Peradeniya (Sri Lanka). Faculty of Science. Dept. of Botany; Hao, Zhanqing [Chinese Academy of Sciences (CAS), Shenyang (China). State Key Lab. of Forest and Soil Ecology. Inst. of Applied Ecology; Hargrove, William W. [USDA-Forest Service Station Headquarters, Asheville, NC (United States). Eastern Forest Environmental Threat Assessment Center; Hart, Terese B. [Lukuru Wildlife Research Foundation, Kinshasa (Democratic Republic of the Congo). Tshuapa-Lomami-Lualaba Project; Hau, Billy C. H. [Univ. of Hong Kong (China). School of Biological Sciences. Kadoorie Inst.; He, Fangliang [Univ. of Alberta, Edmonton, AB (Canada). Dept. of Renewable Resources; Hoffman, Forrest M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Computational Earth Sciences Group; Howe, Robert W. [Univ. of Wisconsin, Green Bay, WI (United States). Dept. of Natural and Applied Sciences; Hubbell, Stephen P. [Smithsonian Tropical Research Inst. (STRI), Panama (Panama). Center for Tropical Forest Science. Forest Global Earth Observatory; Univ. of California, Los Angeles, CA (United States). Dept. of Ecology and Evolutionary Biology; Inman-Narahari, Faith M. [Univ. of Hawaii, Honolulu, HI (United States). College of Tropical Agriculture and Human Resources; Jansen, Patrick A. [Smithsonian Tropical Research Inst. (STRI), Panama (Panama). Center for Tropical Forest Science. Forest Global Earth Observatory; Wageningen Univ. (Netherlands). Resource Ecology Group; Jiang, Mingxi [Chinese Academy of Sciences (CAS), Wuhan (China). Wuhan Botanical Garden; Johnson, Daniel J. [Indiana Univ., Bloomington, IN (United States). Dept. of Biology; Kanzaki, Mamoru [Kyoto Univ. (Japan). Graduate School of Agriculture; Kassim, Abdul Rahman [Forest Research Inst. Malaysia (FRIM), Selangor (Malaysia); Kenfack, David [Smithsonian Tropical Research Inst. (STRI), Panama (Panama). Center for Tropical Forest Science. Forest Global Earth Observatory; National Museum of Natural History, Washington, DC (United States). Dept. of Botany; Kibet, Staline [National Museums of Kenya, Nairobi (Kenya); Univ. of Nairobi (Kenya). Land Resource Management and Agricultural Technology Dept.; Kinnaird, Margaret F. [Mpala Research Centre, Nanyuki (Kenya); Wildlife Conservation Society, New York, NY (United States). Global Conservation Programs; Korte, Lisa [Smithsonian Conservation Biology Inst., Washington, DC (United States). National Zoological Park. Center for Conservation Education and Sustainability; Kral, Kamil [Silva Tarouca Research Inst., Brno (Czech Republic). Dept. of Forest Ecology; Kumar, Jitendra [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Computational Earth Sciences Group; Larson, Andrew J. [Univ. of Montana, Missoula, MT (United States). College of Forestry and Conservation. Dept. of Forest Management; Li, Yide [Chinese Academy of Forestry, Guangzhou (China). Research Inst. of Tropical Forestry; Li, Xiankun [Chinese Academy of Sciences (CAS), Guilin (China). Guangxi Inst. of Botany; Liu, Shirong [Chinese Academy of Forestry, Beijing (China). Research Inst. of Forest Ecology, Environment and Protection; Lum, Shawn K. Y. [Nanyang Technological Univ. (Singapore). National Inst. of Education. Natural Sciences and Science Education Academic Group; Lutz, James A. [Utah State Univ., Logan, UT (United States). Wildland Resources Dept.; Ma, Keping [Chinese Academy of Sciences (CAS), Beijing (China). Inst. of Botany; Maddalena, Damian M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Computational Earth Sciences Group; Makana, Jean-Remy [Wildlife Conservation Society, Brazzaville (Democratic Republic of the Congo); Malhi, Yadvinder [Univ. of Oxford (United Kingdom). School of Geography and the Environment. Environmental Change Inst.; Marthews, Toby [Univ. of Oxford (United Kingdom). School of Geography and the Environment. Environmental Change Inst.; Mat Serudin, Rafizah [Univ. of Brunei Darussalam, Bandar Seri Begawan (Brunei). Faculty of Science. Environmental and Life Sciences; McMahon, Sean M. [Smithsonian Tropical Research Inst. (STRI), Panama (Panama). Center for Tropical Forest Science. Forest Global Earth Observatory; Smithsonian Environmental Research Center, Edgewater, MD (United States). Forest Ecology Group; McShea, William J. [Smithsonian Conservation Biology Inst., Front Royal, VA (United States). National Zoological Park. Conservation Ecology Center; Memiaghe, Hervé R. [Inst. de Recherche en Ecologie Tropicale, Libreville (Gabon). Centre National de la Recherche Scientifique et Technologique; Mi, Xiangcheng [Chinese Academy of Sciences (CAS), Beijing (China). Inst. of Botany; Mizuno, Takashi [Kyoto Univ. (Japan). Graduate School of Agriculture; Morecroft, Michael [Natural England, Sheffield (United Kingdom); Myers, Jonathan A. [Washington Univ., St. Louis, MO (United States). Dept. of Biology; Novotny, Vojtech [New Guinea Binatang Research Centre, Madang (Papua New Guinea); Univ. of South Bohemia, Ceske Budejovice (Czech Republic). Academy of Sciences of the Czech Republic. Faculty of Science. Biology Centre; de Oliveira, Alexandre A. [Univ. of Sao Paulo (Brazil). Inst. of Biosciences. Ecology Dept.; Ong, Perry S. [Univ. of the Philippines Diliman, Quezon City (Philippines). Inst. of Biology; Orwig, David A. [Harvard Univ., Petersham, MA (United States). Harvard Forest; Ostertag, Rebecca [Univ. of Hawaii, Hilo, HI (United States). Dept. of Biology; den Ouden, Jan [Wageningen Univ. (Netherlands). Forest Ecology and Forest Management Group; Parker, Geoffrey G. [Smithsonian Environmental Research Center, Edgewater, MD (United States). Forest Ecology Group; Phillips, Richard P. [Indiana Univ., Bloomington, IN (United States). Dept. of Biology; Sack, Lawren [Univ. of California, Los Angeles, CA (United States). Dept. of Ecology and Evolutionary Biology; Sainge, Moses N. [Tropical Plant Exploration Group (TroPEG), Mundemba (Cameroon); Sang, Weiguo [Chinese Academy of Sciences (CAS), Beijing (China). Inst. of Botany; Sri-ngernyuang, Kriangsak [Maejo Univ., Chiang Mai (Thailand). Faculty of Architecture and Environmental Design; Sukumar, Raman [Indian Inst. of Science, Bangalore (India). Centre for Ecological Sciences; Sun, I-Fang [National Dong Hwa Univ., Hualian (Taiwan). Dept. of Natural Resources and Environmental Studies; Sungpalee, Witchaphart [Maejo Univ., Chiang Mai (Thailand). Faculty of Architecture and Environmental Design; Suresh, Hebbalalu Sathyanarayana [Indian Inst. of Science, Bangalore (India). Centre for Ecological Sciences; Tan, Sylvester [Sarawak Forest Dept., Kuching (Malaysia); Thomas, Sean C. [Univ. of Toronto, ON (Canada). Faculty of Forestry; Thomas, Duncan W. [Washington State Univ., Vancouver, WA (United States). School of Biological Sciences; Thompson, Jill [Centre for Ecology and Hydrology, Penicuik, Scotland (United Kingdom); Univ. of Puerto Rico Rio Pedras, San Juan (Puerto Rico). Dept. of Environmental Science. Inst. for Tropical Ecosystem Studies; Turner, Benjamin L. [Smithsonian Tropical Research Inst. (STRI), Panama (Panama). Center for Tropical Forest Science. Forest Global Earth Observatory; Uriarte, Maria [Columbia Univ., New York, NY (United States). Dept. of Ecology, Evolution and Environmental Biology; Valencia, Renato [Pontifical Catholic Univ. of Ecuador, Quito (Ecuador). Dept. of Biological Sciences; Vallejo, Marta I. [Inst. Alexander von Humboldt, Bogota (Colombia); Vicentini, Alberto [National Inst. of Amazonian Research (INPA), Manaus (Brazil); Vrška, Tomáš [Silva Tarouca Research Inst., Brno (Czech Republic). Dept. of Forest Ecology; Wang, Xihua [East China Normal Univ. (ECNU), Shanghai (China). School of Ecological and Environmental Sciences; Wang, Xugao [Lukuru Wildlife Research Foundation, Kinshasa (Democratic Republic of the Congo). Tshuapa-Lomami-Lualaba Project; Weiblen, George [Univ. of Minnesota, St. Paul, MN (United States). Dept. of Plant Biology; Wolf, Amy [Univ. of Wisconsin, Green Bay, WI (United States). Dept. of Biology. Dept. of Natural and Applied Sciences; Xu, Han [Chinese Academy of Forestry, Guangzhou (China). Research Inst. of Tropical Forestry; Yap, Sandra [Univ. of the Philippines Diliman, Quezon City (Philippines). Inst. of Biology; Zimmerman, Jess [Univ. of Puerto Rico Rio Piedras, San Juan (Puerto Rico). Dept. of Environmental Science. Inst. for Tropical Ecosystem Studies

    2014-09-25

    Global change is impacting forests worldwide, threatening biodiversity and ecosystem services, including climate regulation. Understanding how forests respond is critical to forest conservation and climate protection. This review describes an international network of 59 long-term forest dynamic research sites useful for characterizing forest responses to global change. The broad suite of measurements made at the CTFS-ForestGEO sites make it possible to investigate the complex ways in which global change is impacting forest dynamics. ongoing research across the network is yielding insights into how and why the forests are changing, and continued monitoring will provide vital contributions to understanding worldwide forest diversity and dynamics in a era of global change

  4. Evidence for Two Sites of Superoxide Production by Mitochondrial NADH-Ubiquinone Oxidoreductase (Complex I)*

    Science.gov (United States)

    Treberg, Jason R.; Quinlan, Casey L.; Brand, Martin D.

    2011-01-01

    Complex I (NADH-ubiquinone oxidoreductase) can form superoxide during forward electron flow (NADH-oxidizing) or, at sufficiently high protonmotive force, during reverse electron transport from the ubiquinone (Q) pool (NAD+-reducing). We designed an assay system to allow titration of the redox state of the superoxide-generating site during reverse electron transport in rat skeletal muscle mitochondria: a protonmotive force generated by ATP hydrolysis, succinate:malonate to alter electron supply and modulate the redox state of the Q pool, and inhibition of complex III to prevent QH2 oxidation via the Q cycle. Stepwise oxidation of the QH2/Q pool by increasing malonate concentration slowed the rates of both reverse electron transport and rotenone-sensitive superoxide production by complex I. However, the superoxide production rate was not uniquely related to the resultant potential of the NADH/NAD+ redox couple. Thus, there is a superoxide producer during reverse electron transport at complex I that responds to Q pool redox state and is not in equilibrium with the NAD reduction state. In contrast, superoxide production during forward electron transport in the presence of rotenone was uniquely related to NAD redox state. These results support a two-site model of complex I superoxide production; one site in equilibrium with the NAD pool, presumably the flavin of the FMN moiety (site IF) and the other dependent not only on NAD redox state, but also on protonmotive force and the reduction state of the Q pool, presumably a semiquinone in the Q-binding site (site IQ). PMID:21659507

  5. Inventory of forest and rangeland and detection of forest stress. [Manitou, Colorado, Atlanta, Georgia, and Black Hills test sites

    Science.gov (United States)

    Heller, R. C.; Aldrich, R. C.; Weber, F. P.; Driscoll, R. S. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. Eucalyptus tree stands killed by low temperatures in December 1972 were outlined by image enhancement of two separate dates of ERTS-1 images (January 22, 1973-I.D. 1183-18175 and April 22, 1973-I.D. 1273-18183). Three stands larger than 500 meters in size were detected very accurately. In Colorado, range and grassland communities were analyzed by visual interpretation of color composite scene I.D. 1028-17135. It was found that mixtures of plant litter, amount and kind of bare soil, and plant foliage cover made classification of grasslands very difficult. Changes in forest land use were detected on areas as small as 5 acres when ERTS-1 color composite scene 1264-15445 (April 13, 1973) was compared with 1966 ASCS index mosaics (scale 1:60,000). Verification of the changes were made from RB-57 underflight CIR transparencies (scale 1:120,000).

  6. Influence of competition and age on tree growth in structurally complex old-growth forests in northern Minnesota, USA

    Science.gov (United States)

    Tuomas Aakala; Shawn Fraver; Anthony W. D' Amato; Brian J. Palik

    2013-01-01

    Factors influencing tree growth in structurally complex forests remain poorly understood. Here we assessed the influence of competition on Pinus resinosa (n = 224) and Pinus strobus (n = 90) growth in four old-growth stands in Minnesota, using mixed effects models. A subset of trees, with...

  7. Modeling complex effects of multiple environmental stresses on carbon dynamics of Mid-Atlantic temperate forests

    Science.gov (United States)

    Yude Pan; Richard Birdsey; John Hom; Kevin McCullough

    2007-01-01

    We used our GIS variant of the PnET-CN model to investigate changes of forest carbon stocks and fluxes in Mid-Atlantic temperate forests over the last century (1900-2000). Forests in this region are affected by multiple environmental changes including climate, atmospheric CO2 concentration, N deposition and tropospheric ozone, and extensive land disturbances. Our...

  8. Saving the Lower Tana River Forest Complex: Can P-GIS help?

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

    within and around the forests, local administrators as well public and private conservation agencies indicate that a number of factors are responsible for the current destruction of the forests and hence the threat to biodiversity and other economic and ecological benefits. These are: 1. The search for food security. The forest ...

  9. Using model analyses and surface-atmosphere exchange measurements from the Howland AmeriFlux Site in Maine, USA, to improve understanding of forest ecosystem C cycling

    Energy Technology Data Exchange (ETDEWEB)

    Hollinger, David Y.; Davidson, Eric A.; Richardson, Andrew D.; Dail, D. B.; Scott, N.

    2013-03-25

    Summary of research carried out under Interagency Agreement DE-AI02-07ER64355 with the USDA Forest Service at the Howland Forest AmeriFlux site in central Maine. Includes a list of publications resulting in part or whole from this support.

  10. Jointly optimizing selection of fuel treatments and siting of forest biomass-based energy production facilities for landscape-scale fire hazard reduction.

    Science.gov (United States)

    Peter J. Daugherty; Jeremy S. Fried

    2007-01-01

    Landscape-scale fuel treatments for forest fire hazard reduction potentially produce large quantities of material suitable for biomass energy production. The analytic framework FIA BioSum addresses this situation by developing detailed data on forest conditions and production under alternative fuel treatment prescriptions, and computes haul costs to alternative sites...

  11. Site index equations and mean annual increment equations for Pacific Northwest Research Station forest inventory and analysis inventories, 1985-2001.

    Science.gov (United States)

    Erica J. Hanson; David L. Azuma; Bruce A. Hiserote

    2003-01-01

    Site index equations and mean annual increment equations used by the Forest Inventory and Analysis Program at the Portland Forestry Sciences Laboratory, Pacific Northwest Research Station, Forest Service, U.S. Department of Agriculture. The equations are for 24 tree species in California, Oregon, and Washington.

  12. Woody vegetation following even-aged, uneven-aged, and no-harvest treatments on the Missouri Ozark Forest Ecosystem Project Sites

    Science.gov (United States)

    John M. Kabrick; Randy G. Jensen; Stephen R. Shifley; David R. Larsen

    2002-01-01

    The Missouri Ozark Forest Ecosystem Project (MOFEP) experimentally tests forest ecosystem response to (a) even-aged management with clearcutting, (b) uneven-aged management with single-tree and group selection, and (c) no-harvesting. The nine MOFEP experimental sites in the southeast Missouri Ozarks are small landscapes ranging from 772 ac (312 ha) to 1,271 ac (514 ha...

  13. Mutations at the Qo-Site of the Cytochrome bc1 Complex Strongly Affect Oxygen Binding

    DEFF Research Database (Denmark)

    Husen, Peter; Solov'yov, Ilia A

    2017-01-01

    The homodimeric bc1 protein complex is embedded in membranes of mitochondria and photosynthetic bacteria, where it transports protons across the membrane to maintain an electrostatic potential used to drive ATP synthesis as part of the respiratory or photosynthetic pathways. The reaction cycle...... investigation employs molecular dynamics simulations to study the effect of mutations in the Qo binding sites of the bc1 complex on the ability of oxygen molecules to migrate to and bind at various locations within the complex. It is found that the mutations strongly affect the ability of oxygen to bind...

  14. Faunal diversity in a semi-evergreen forest of Bornadi-Khalingduar Complex of Assam, India

    Directory of Open Access Journals (Sweden)

    Pallabi Chakraborty

    2015-09-01

    Full Text Available The Bornadi-Khalingduar Complex under the Manas Tiger Reserve, Assam is known to be an important area for wildlife movement to and from India and Bhutan. The contiguous landscape encompassing the two neighbouring countries provides a good habitat for diversity of wildlife and also as an important corridor area.  We carried out an opportunistic camera-trapping exercise to document the faunal diversity in the area. A month-long exercise photo-captured a total of 19 species belonging to 12 families, including the Leopard, Wild Dog, Leopard Cat, Binturong, Elephant, Sambar, Barking Deer and various birds. These findings of the study reveal the importance, threats and potential of the area and recommendations have been made to secure this corridor for continuous animal movement. Anthropogenic disturbance is a major deterrent to undisturbed animal movement in this area with resultant forest fragmentation and degradation. This indicates the need for effective conservation strategies in order to maintain the remnants of this corridor complex.  

  15. 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...

  16. 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;...

  17. Emotional, restorative and vitalizing effects of forest and urban environments at four sites in Japan.

    Science.gov (United States)

    Takayama, Norimasa; Korpela, Kalevi; Lee, Juyoung; Morikawa, Takeshi; Tsunetsugu, Yuko; Park, Bum-Jin; Li, Qing; Tyrväinen, Liisa; Miyazaki, Yoshifumi; Kagawa, Takahide

    2014-07-15

    The present study investigated the well-being effects of short-term forest walking and viewing ("forest bathing"). The hypothesis in our study was that both environment (forest vs. urban) and activity (walking and viewing) would influence psychological outcomes. An additional aim was to enhance basic research using several psychological methods. We conducted the experiments using 45 respondents in four areas of Japan from August to September, 2011. The hypothesis in our study was supported, because significant interaction terms between the environment and activity were confirmed regarding the Profile of Mood States (POMS) indexes, Restorative Outcome Scale (ROS) and Subjective Vitality Scale (SVS). No statistical differences between the two experimental groups in any of the ten scales were found before the experiment. However, feelings of vigor and positive effects, as well as feelings of subjective recovery and vitality were stronger in the forest environment than in the urban environment.

  18. Emotional, Restorative and Vitalizing Effects of Forest and Urban Environments at Four Sites in Japan

    Directory of Open Access Journals (Sweden)

    Norimasa Takayama

    2014-07-01

    Full Text Available The present study investigated the well-being effects of short-term forest walking and viewing (“forest bathing”. The hypothesis in our study was that both environment (forest vs. urban and activity (walking and viewing would influence psychological outcomes. An additional aim was to enhance basic research using several psychological methods. We conducted the experiments using 45 respondents in four areas of Japan from August to September, 2011. The hypothesis in our study was supported, because significant interaction terms between the environment and activity were confirmed regarding the Profile of Mood States (POMS indexes, Restorative Outcome Scale (ROS and Subjective Vitality Scale (SVS. No statistical differences between the two experimental groups in any of the ten scales were found before the experiment. However, feelings of vigor and positive effects, as well as feelings of subjective recovery and vitality were stronger in the forest environment than in the urban environment.

  19. NPP Tropical Forest: Consistent Worldwide Site Estimates, 1967-1999, R1

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains documented field measurements of NPP components for 39 old-growth tropical forests distributed worldwide between latitudes 23.58 N and 23.58...

  20. Leaf Area Influence on Surface Layer in a Deciduous Forest. Part I; Site Description

    Science.gov (United States)

    Sakai, Ricardo K.; Fitzjarrald, David R.; Moore, Kathleen E.; Sicker, John W.; Munger, William; Goulden, Michael L.; Wofsy, Steven C.

    1996-01-01

    A study over a deciduous forest located in middle Massachusetts (USA) has been performed to examine the role of leaves in the forest-atmosphere interaction. Due to the seasonal presence of leaves, a deciduous forest is a 'good laboratory' to study this interaction. In this first part, a description of a 30 m micrometeorological tower as well a qualitative description of some meteorological parameters are presented. The presence of leaves affects the forest in several ways. There is a decrease of upward PAR (Photosynthetically Active Radiation) due to absorption of visible light in the canopy. Water vapor concentration increases, and the CO2 concentration decreases in the surface layer as the canopy starts to be foliated. The physical presence of the leaves is felt in other quantities such as the global albedo and the subcanopy environment.

  1. Four-site cooperative spin crossover in a mononuclear FeII complex

    DEFF Research Database (Denmark)

    Lennartson, Anders; Bond, Andrew D; Piligkos, Stergios

    2012-01-01

    Round and round: A mononuclear Fe(II) complex (see picture) with an N(4)S(2) coordination set has been characterized in four polymorphic forms. Two of the polymorphs display four-site cooperative spin crossover (SCO), shown conclusively by the crystal structure of a fully ordered 1:3 high-spin/lo...

  2. Update of a footprint-based approach for the characterisation of complex measurement sites

    DEFF Research Database (Denmark)

    Goeckede, M.; Markkanen, T.; Hasager, C.B.

    2006-01-01

    Horizontal heterogeneity can significantly affect the flux data quality at monitoring sites in complex terrain. In heterogeneous conditions, the adoption of the eddy-covariance technique is contraindicated by the lack of horizontal homogeneity and presence of advective conditions. In addition, un...

  3. Remedial investigation and feasibility study for the Lawrence Livermore National Laboratory Site 300 Pit 7 Complex

    Energy Technology Data Exchange (ETDEWEB)

    Taffet, M.J. (Lawrence Livermore National Lab., CA (USA)); Oberdorfer, J.A. (San Jose State Univ., CA (USA)); McIlvride, W.A. (Weiss Associates, Oakland, CA (USA))

    1989-10-01

    This report summarizes the results and conclusions of the investigation of tritium and other compounds in ground water in the vicinity of landfills at the Lawrence Livermore National Laboratory (LLNL) Site 300 Pit 7 Complex. 91 refs., 110 figs., 43 tabs.

  4. VARIABLE BOUND-SITE CHARGING CONTRIBUTIONS TO SURFACE COMPLEXATION MASS ACTION EXPRESSIONS

    Science.gov (United States)

    One and two pK models of surface complexation reactions between reactive surface sites (>SOH) and the proton (H+) use mass action expressions of the form: Ka={[>SOHn-1z-1]g>SOH(0-1)aH+EXP(-xeY/kT)}/{[>SOHnz]g>SOH(n)} where Ka=the acidity constant, [ ]=reactive species concentrati...

  5. Effects Of Very Intensive Forest Biomass Harvesting On Short And Long Term Site Productivity

    DEFF Research Database (Denmark)

    Clarke, Nicholas; Callesen, Ingeborg; Helmisaari, Heljä-Sisko

    2008-01-01

    Intensified forest biomass utilisation causes export of substantial amounts of nutrients from the forest ecosystem. Compared to conventional stems-only harvesting, the most intensive biomass sce nario causes increases in nutrient exports of up to 6-7 times whereas the biomass export increases onl...... balances are used for compensation recommendations. We do not discuss effects like decrease in soil organic matter, or other indirect effects like soil compaction, weed problems, and microclimatic effects....

  6. The Ecosystem-Economy Relationship: Insights from Six Forested LTER Sites

    Science.gov (United States)

    Paul N. Courant; Ernie Niemi; Ed. Whitelaw

    1997-01-01

    The debate over forest-management policy in the U.S. often is cast as a choice between jobs and [pick the environmental attribute of your choice]. The purpose of this paper is neither to rehash nor to characterize these conflicts, but to discuss insights into them that have emerged from an examination of the forest-economy relationship in different regions of the U.S....

  7. Ash cap influences on site productivity and fertilizer response in forests of the Inland Northwest

    Science.gov (United States)

    Mariann T. Garrison-Johnston; Peter G. Mika; Dan L. Miller; Phil Cannon; Leonard R. Johnson

    2007-01-01

    Data from 139 research sites throughout the Inland Northwest were analyzed for effects of ash cap on site productivity, nutrient availability and fertilization response. Stand productivity and nitrogen (N) fertilizer response were greater on sites with ash cap than on sites without. Where ash was present, depth of ash had no effect on site productivity or N fertilizer...

  8. Forest soils of Ethiopian highlands: Their characteristics in relation to site history. Studies based on stable isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Eshetu, Zewdu [Swedish Univ. of Agricultural Sciences, Umeaa (Sweden). Dept. of Forest Ecology

    2000-07-01

    Isotopic composition and nutrient contents of soils in forests, pastures and cultivated lands were studied in Menagesha and Wendo-Genet, Ethiopia, in order to determine the effects of land use changes on soil organic matter, the N cycle and the supply of other nutrients. In the Menagesha forest, which according to historical accounts was planted in the year 1434-1468, {delta}{sup 13}C values at > 20 cm soil depth of from -23 to -17 per mille and in the surface layers of from -27 to -24 per mille suggest that C{sub 4} grasses or crops were important components of the past vegetation. At Wendo-Genet, the {delta}{sup 13}C values in the topsoils of from -23 to -16 per mille and in the > 20 cm of from -16 to -14 per mille indicated more recent land use changes from grassland to forest. At Menagesha, {delta}{sup 15}N values shifted from -8.8 per mille in the litter to +6.8 per mille in the > 20 cm. The low {delta}{sup 15}N in the litter (-3 per mille) and topsoils (0 per mille) suggest a closed N cycle at Menagesha. At Wendo-Genet, the high {delta}{sup 15}N (3.4-9.8 per mille) and low total N concentrations suggests a more open N cycle with greater N losses. At Menagesha, the variation in soil nutrient contents followed the patterns of %C and %N. At the mid-altitudes, where there had been undisturbed forest cover for >500 years, %N and %C were higher and the surface layers showed high accumulation of Ca and S. The strong relation between %C and CEC{sub t} suggests that organic matter increases the nutrient retention capacity of these soils. Exchangeable and total Ca were strongly related (r{sup 2} = 0.95, P<0.001). It is suggested that the presence of forests in this otherwise bare landscape leads to interception of base cations in dust, which can help to sustain a productive forest. The studies show that the approach to combine stable isotopes with nutrient elements is especially useful when studying the chemical properties of forest soils in relation to site history

  9. PreBötzinger complex and pacemaker neurons: hypothesized site and kernel for respiratory rhythm generation

    DEFF Research Database (Denmark)

    Rekling, J C; Feldman, J L

    1998-01-01

    Identification of the sites and mechanisms underlying the generation of respiratory rhythm is of longstanding interest to physiologists and neurobiologists. Recently, with the development of novel experimental preparations, especially in vitro en bloc and slice preparations of rodent brainstem......, progress has been made In particular, a site in the ventrolateral medulla, the preBötzinger Complex, is hypothesized to contain neuronal circuits generating respiratory rhythm. Lesions or disruption of synaptic transmission within the preBötzinger Complex, either in vivo or in vitro, can abolish...... respiratory activity. Furthermore, the persistence of respiratory rhythm following interference with postsynaptic inhibition and the subsequent discovery of neurons with endogenous bursting properties within the preBötzinger Complex have led to the hypothesis that rhythmogenesis results from synchronized...

  10. Species boundaries and cryptic lineage diversity in a Philippine forest skink complex (Reptilia; Squamata; Scincidae: Lygosominae).

    Science.gov (United States)

    Linkem, Charles W; Hesed, Kyle Miller; Diesmos, Arvin C; Brown, Rafe M

    2010-08-01

    In the megadiverse conservation hotspot of the Philippines, biodiversity is not uniformly distributed throughout the archipelago, but hierarchically partitioned into islands and island groups that were conjoined during the mid- to late-Pleistocene. Few species groups are widely distributed throughout the archipelago, but some exceptions exist, such as the common scincid lizards of the Sphenomorphus jagori complex (including S. jagori, S. coxi, and S. abdictus). Using mtDNA haplotype data we test biogeographic and taxonomic predictions in these abundant, large-bodied, forest floor lizards and arrive at conclusions that differ significantly from both past, and current, appraisals of species diversity. In contrast to expectations based on existing taxonomy (three species, each with two subspecies), we find evidence of at least eleven highly divergent species lineages diagnosed by haplotypic variation. Each lineage corresponds to a biogeographically circumscribed distribution (i.e., isolated islands or geological components of islands), suggesting lineage cohesion and allopatric differentiation. Parametric bootstrapping tests reject taxonomic and biogeographic hypotheses and suggest a complex pattern of unpredicted relationships. Only one of the former species (S. jagori) appears as a monophyletic entity (including four allopatric, highly divergent lineages that we suspect may represent evolutionary species), and the remaining species are paraphyletic, necessitating a comprehensive future taxonomic revision. The pattern of biogeographic provincialism and hidden cryptic species diversity detected here leads us to suspect that even the most common, presumably well-studied, and widespread species complexes in the Philippines are in need of thorough analysis with modern genetic and phylogenetic techniques. Such studies of speciation genetics in these common, widely distributed groups may lead to a better understanding of the genetic underpinnings of biodiversity, allow for

  11. Analysis of Flood Hazards for the Materials and Fuels Complex at the Idaho National Laboratory Site

    Energy Technology Data Exchange (ETDEWEB)

    Skaggs, Richard; Breithaupt, Stephen A.; Waichler, Scott R.; Kim, Taeyun; Ward, Duane L.

    2010-11-01

    Researchers at Pacific Northwest National Laboratory conducted a flood hazard analysis for the Materials and Fuels Complex (MFC) site located at the Idaho National Laboratory (INL) site in southeastern Idaho. The general approach for the analysis was to determine the maximum water elevation levels associated with the design-basis flood (DBFL) and compare them to the floor elevations at critical building locations. Two DBFLs for the MFC site were developed using different precipitation inputs: probable maximum precipitation (PMP) and 10,000 year recurrence interval precipitation. Both precipitation inputs were used to drive a watershed runoff model for the surrounding upland basins and the MFC site. Outflows modeled with the Hydrologic Engineering Centers Hydrologic Modeling System were input to the Hydrologic Engineering Centers River Analysis System hydrodynamic flood routing model.

  12. [Dimensional characteristics and spatial distribution patterns of pit and mound complexes in Pinus koraiensis-dominated broadleaved mixed forest].

    Science.gov (United States)

    Duan, Wen-Biao; Wei, Quan-Shuai; Qiao, Lu; Chen, Li-Xin; Wang, Ting; Zhang, Xin; Gu, Wei; Sun, Hu

    2014-11-01

    Characteristics of pit and mound complexes in different sizes of forest gaps and closed stands and their distribution patterns were compared and analyzed. The results showed that mean mound width, mound height, mound thickness of all pit and mound complexes were larger than corresponding mean pit length, pit width, pit depth in large, medium and small gaps as well as in closed stands. Mound width, mound height, mound thickness, pit length, pit width, pit depth were the largest in large gap, being 2.85, 0.37, 2.00, 2.99, 2.10, 0.39 m, respectively, and the smallest in closed stands, being 2.35, 0.19, 1.60, 2.66, 1.65, 0.21, respectively. Mean mound volume (1.66 m3) was larger than mean pit volume (1.44 m3). The difference in characteristic values between the most of pit and mound complexes was significant for the same size of forest gap, not significant for closed stands, significant for different sizes of forest gaps and closed stands. Most of characteristic values for pit and mound complexes within the plot in 2012 were significantly less than those in 2011. 89.5% and 60.5% of type and shape of pit and mound complexes were hinge and semiellipse, respectively. Their distribution was relatively centralized.

  13. Species richness and structure of an anuran community in an Atlantic Forest site in southern Brazil

    Directory of Open Access Journals (Sweden)

    Adriele Karlokoski Cunha

    2010-06-01

    Full Text Available The species richness and spatial distribution of an anuran community were studied over 12 months in an Atlantic Forest area in São José dos Pinhais Municipality, Paraná State, southern Brazil. During field surveys, we registered 32 species from ten families: Brachycephalidae (2, Bufonidae (2, Centrolenidae (1, Cycloramphidae (1, Hemiphractidae (1, Hylidae (18, Hylodidae (1, Leiuperidae (2, Leptodactylidae (3, and Microhylidae (1. Sixteen species were registered in open areas, while seventeen species were found on forest borders and twenty species in forest areas. In relation to the microhabitat utilization, species were registered according to stratum of vocalization: 1 on the ground (eight; 2 in the water (two; 3 in the lower stratum (eleven; 4 in the intermediate stratum (five; 5 in the upper stratum (four. Five species were abundant (15.6%, while twelve were common (37.5%, and fifteen were considered rare (46.9%. The biological aspects of the majority of the species described in this work as related to forest areas are not well known. This fact reinforces the importance of Atlantic Forest conservation.

  14. Calakmul model forest: Productive ecology proposal

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    The Calakmul Model Forest is located in the Yucatan Peninsula, adjacent to a biosphere reserve. The region is tropical, covered with medium and low forest having great biodiversity and a variety of soil types. Poor natural resource management methods used by settlers and alteration of part of the original forested area by traditional agricultural systems have given rise to a complex variety of ecosystems and a number of problems related to forestry, ecology, and society. The Model Forest Project described in this report is intended to lead to land use diversification, forest conservation, ecological management of the forest, increased awareness of the importance of the forest among local residents, and preservation of archaeological sites. The report also describes the forest`s biogeographical characteristics, the local economy, the current resource management situation, and activities to be undertaken by the project.

  15. Surface complexation modeling of uranyl adsorption on corrensite from the Waste Isolation Pilot Plant Site

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sang-Won; Leckie, J.O. [Stanford Univ., CA (United States); Siegel, M.D. [Sandia National Labs., Albuquerque, NM (United States)

    1995-09-01

    Corrensite is the dominant clay mineral in the Culebra Dolomite at the Waste Isolation Pilot Plant. The surface characteristics of corrensite, a mixed chlorite/smectite clay mineral, have been studied. Zeta potential measurements and titration experiments suggest that the corrensite surface contains a mixture of permanent charge sites on the basal plane and SiOH and AlOH sites with a net pH-dependent charge at the edge of the clay platelets. Triple-layer model parameters were determined by the double extrapolation technique for use in chemical speciation calculations of adsorption reactions using the computer program HYDRAQL. Batch adsorption studies showed that corrensite is an effective adsorbent for uranyl. The pH-dependent adsorption behavior indicates that adsorption occurs at the edge sites. Adsorption studies were also conducted in the presence of competing cations and complexing ligands. The cations did not affect uranyl adsorption in the range studied. This observation lends support to the hypothesis that uranyl adsorption occurs at the edge sites. Uranyl adsorption was significantly hindered by carbonate. It is proposed that the formation of carbonate uranyl complexes inhibits uranyl adsorption and that only the carbonate-free species adsorb to the corrensite surface. The presence of the organic complexing agents EDTA and oxine also inhibits uranyl sorption.

  16. Integrative measurements focusing on carbon, energy and water fluxes at the forest site 'Hohes Holz' and the grassland 'Grosses Bruch'

    Science.gov (United States)

    Rebmann, Corinna; Claudia, Schütze; Sara, Marañón-Jiménez; Sebastian, Gimper; Matthias, Zink; Luis, Samaniego; Matthias, Cuntz

    2017-04-01

    The reduction of greenhouse gas (GHG) emissions and the optimization of Carbon sequestration by ecosystems have become priority objectives for current climate change policies. In this context, the long term research project TERENO and the research infrastructure ICOS have been established. The eddy covariance technique allows obtaining an integrative estimate of the ecosystem carbon, water and energy balances at the ecosystem level. The relative contributions of evaporation and transpiration as well as carbon sources and sinks need, however, to be determined separately for thorough process understanding. Two different ecosystem observatories have recently been established in the Magdeburger Börde: a deciduous forest (Hohes Holz) and a meadow (Grosses Bruch). A comprehensive system of instrumentation provides continuous data for the evaluation of energy, water and carbon fluxes at the 1500 ha large forest site, including a 50 m high eddy covariance (EC) tower for micrometeorological investigations in different heights above and below canopy, throughfall and stem flow sensors, a soil moisture and temperature sensor network, soil respiration chambers, sap flow sensors, and ancillary analysis of trees such a dendrometer and leaf area index measurements. Eddy covariance measurements allow the assessment of the carbon (Net Ecosystem Exchange, NEE) and water balance at the ecosystem scale. To better understand the contributing processes we partition water und carbon fluxes of the forest ecosystem by different methods. Tower-based data of NEE are therefore complemented and validated by continuous automatic and manual campaign measurements of soil effluxes and their drivers. Water fluxes into the ecosystem are partitioned by stem flow and throughfall measurements and a distributed soil moisture network. Gap fraction in the forest has a strong influence on the distribution on the water fluxes and is therefore determined on a regular basis. Since the establishment of the

  17. Variation in soil carbon dioxide efflux at two spatial scales in a topographically complex boreal forest

    Science.gov (United States)

    Kelsey, Katharine C.; Wickland, Kimberly P.; Striegl, Rob; Neff, Jason C.

    2012-01-01

    Carbon dynamics of high-latitude regions are an important and highly uncertain component of global carbon budgets, and efforts to constrain estimates of soil-atmosphere carbon exchange in these regions are contingent on accurate representations of spatial and temporal variability in carbon fluxes. This study explores spatial and temporal variability in soilatmosphere carbon dynamics at both fine and coarse spatial scales in a high-elevation, permafrost-dominated boreal black spruce forest. We evaluate the importance of landscape-level investigations of soil-atmosphere carbon dynamics by characterizing seasonal trends in soil-atmosphere carbon exchange, describing soil temperature-moisture-respiration relations, and quantifying temporal and spatial variability at two spatial scales: the plot scale (0–5 m) and the landscape scale (500–1000 m). Plot-scale spatial variability (average variation on a given measurement day) in soil CO2 efflux ranged from a coefficient of variation (CV) of 0.25 to 0.69, and plot-scale temporal variability (average variation of plots across measurement days) in efflux ranged from a CV of 0.19 to 0.36. Landscape-scale spatial and temporal variability in efflux was represented by a CV of 0.40 and 0.31, respectively, indicating that plot-scale spatial variability in soil respiration is as great as landscape-scale spatial variability at this site. While soil respiration was related to soil temperature at both the plot- and landscape scale, landscape-level descriptions of soil moisture were necessary to define soil respiration-moisture relations. Soil moisture variability was also integral to explaining temporal variability in soil respiration. Our results have important implications for research efforts in high-latitude regions where remote study sites make landscape-scale field campaigns challenging.

  18. Effects of silvicultural management intensity on fluxes of dissolved and particulate organic matter in 27 forest sites of the Biodiversity Exploratories

    Science.gov (United States)

    Michalzik, Beate; Bischoff, Sebastian; Levia, Delphis; Schwarz, Martin; Escher, Peter; Wilcke, Wolfgang; Thieme, Lisa; Kerber, Katja; Kaupenjohann, Martin; Siemens, Jan

    2017-04-01

    In forested ecosystems, throughfall and stemflow function as key components in the cycling of water and associated biogeochemistry. Analysing annual flux data collected from 27 intensively monitored forest sites of the Biodiversity Exploratories, we found throughfall fluxes of DOC (dissolved organic carbon) linearly related (R2 = 0.40, p losses of DOC and POC from the litter layer of forests increased significantly with increasing forest management intensity. The observed relationships revealed by intensive flux monitoring are important because they allow us to link organic matter fluxes to forest metrics of larger forested areas (e.g. derived from LiDAR imagery), and hence to model and up-scale water-bound OC dynamics to the landscape level.

  19. Integration of Remote Sensing Products with Ground-Based Measurements to Understand the Dynamics of Nepal's Forests and Plantation Sites

    Science.gov (United States)

    Gilani, H.; Jain, A. K.

    2016-12-01

    This study assembles information from three sources - remote sensing, terrestrial photography and ground-based inventory data, to understand the dynamics of Nepal's tropical and sub-tropical forests and plantation sites for the period 1990-2015. Our study focuses on following three specific district areas, which have conserved forests through social and agroforestry management practices: 1. Dolakha district: This site has been selected to study the impact of community-based forest management on land cover change using repeat photography and satellite imagery, in combination with interviews with community members. The study time period is during the period 1990-2010. We determined that satellite data with ground photographs can provide transparency for long term monitoring. The initial results also suggests that community-based forest management program in the mid-hills of Nepal was successful. 2. Chitwan district: Here we use high resolution remote sensing data and optimized community field inventories to evaluate potential application and operational feasibility of community level REDD+ measuring, reporting and verification (MRV) systems. The study uses temporal dynamics of land cover transitions, tree canopy size classes and biomass over a Kayar khola watershed REDD+ study area with community forest to evaluate satellite Image segmentation for land cover, linear regression model for above ground biomass (AGB), and estimation and monitoring field data for tree crowns and AGB. We study three specific years 2002, 2009, 2012. Using integration of WorldView-2 and airborne LiDAR data for tree species level. 3. Nuwakot district: This district was selected to study the impact of establishment of tree plantation on total barren/fallow. Over the last 40 year, this area has went through a drastic changes, from barren land to forest area with tree species consisting of Dalbergia sissoo, Leucaena leucocephala, Michelia champaca, etc. In 1994, this district area was registered

  20. Identification of Ubiquinol Binding Motifs at the Qo-Site of the Cytochrome bc1 Complex

    DEFF Research Database (Denmark)

    Barragan, Angela M.; Crofts, Antony R.; Schulten, Klaus

    2015-01-01

    all atom molecular dynamics and quantum chemical calculations to reveal the binding modes of quinol at the Qo-site of the bc1 complex from Rhodobacter capsulatus. The calculations suggest a novel configuration of amino acid residues responsible for quinol binding and support a mechanism for proton......Enzymes of the bc1 complex family power the biosphere through their central role in respiration and photosynthesis. These enzymes couple the oxidation of quinol molecules by cytochrome c to the transfer of protons across the membrane, to generate a proton-motive force that drives ATP synthesis. Key...... for the function of the bc1 complex is the initial redox process that involves a bifurcated electron transfer in which the two electrons from a quinol substrate are passed to different electron acceptors in the bc1 complex. The electron transfer is coupled to proton transfer. The overall mechanism of quinol...

  1. Individual tree crown approach for predicting site index in boreal forests using airborne laser scanning and hyperspectral data

    Science.gov (United States)

    Kandare, Kaja; Ørka, Hans Ole; Dalponte, Michele; Næsset, Erik; Gobakken, Terje

    2017-08-01

    Site productivity is essential information for sustainable forest management and site index (SI) is the most common quantitative measure of it. The SI is usually determined for individual tree species based on tree height and the age of the 100 largest trees per hectare according to stem diameter. The present study aimed to demonstrate and validate a methodology for the determination of SI using remotely sensed data, in particular fused airborne laser scanning (ALS) and airborne hyperspectral data in a forest site in Norway. The applied approach was based on individual tree crown (ITC) delineation: tree species, tree height, diameter at breast height (DBH), and age were modelled and predicted at ITC level using 10-fold cross validation. Four dominant ITCs per 400 m2 plot were selected as input to predict SI at plot level for Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.). We applied an experimental setup with different subsets of dominant ITCs with different combinations of attributes (predicted or field-derived) for SI predictions. The results revealed that the selection of the dominant ITCs based on the largest DBH independent of tree species, predicted the SI with similar accuracy as ITCs matched with field-derived dominant trees (RMSE: 27.6% vs 23.3%). The SI accuracies were at the same level when dominant species were determined from the remotely sensed or field data (RMSE: 27.6% vs 27.8%). However, when the predicted tree age was used the SI accuracy decreased compared to field-derived age (RMSE: 27.6% vs 7.6%). In general, SI was overpredicted for both tree species in the mature forest, while there was an underprediction in the young forest. In conclusion, the proposed approach for SI determination based on ITC delineation and a combination of ALS and hyperspectral data is an efficient and stable procedure, which has the potential to predict SI in forest areas at various spatial scales and additionally to improve existing SI

  2. Mercury concentrations and pools in four Sierra Nevada forest sites, and relationships to organic carbon and nitrogen

    Directory of Open Access Journals (Sweden)

    D. Obrist

    2009-05-01

    Full Text Available This study presents data on mercury (Hg concentrations, stochiometric relations to carbon (C and nitrogen (N, and Hg pool sizes in four Sierra Nevada forest sites of similar exposure and precipitation regimes, and hence similar atmospheric deposition, to evaluate how ecosystem parameters control Hg retention in ecosystems. In all four sites, the largest amounts of Hg reside in soils which account for 94–98% of ecosystem pools. Hg concentrations and Hg/C ratios increase in the following order: Green Needles/Leavesr2=0.58 and N and C (r2=0.64 in decomposing litter, but a positive correlation between litter Hg and N (r2=0.70. These inverse relations may reflect preferential retention of N and Hg over C during decomposition, or may be due to older age of decomposed litter layers which are exposed to longer-term atmospheric Hg deposition in the field. The results indicate that litter Hg levels depend on decomposition stage and may not follow generally observed positive relationships between Hg and organic C.

    Mineral soil layers show strong positive correlations of Hg to C across all sites and soil horizons (r2=0.83, but Hg concentrations are even more closely related to N with a similar slope to that observed in litter (r2=0.92. Soil N levels alone explain over 90% of Hg pool sizes across the four Sierra Nevada forest sites. This suggests that soil organic N and C groups provide sorption sites for Hg to retain atmospheric deposition. However, the patterns could be due to indirect relationships where high soil N and C levels reflect high ecosystem productivity which leads to corresponding high atmospheric Hg deposition inputs via leaf litterfall and plant senescence. Our results also show that two of the sites previously affected by

  3. New species of Hermanella complex (Ephemeroptera: Leptophlebiidae) from Brazilian Atlantic Forest.

    Science.gov (United States)

    Do Nascimento, Jeane M C; Salles, Frederico F

    2013-01-01

    In the present work, based on material from Brazilian Atlantic Forest, four new species of the Hermanella complex are described. The main characteristics that distinguish the new species from its congeners are, in Hermanella amere sp. nov.: (1) subgenital plate yellow, with wide projection near base of forceps; (2) penis lobe with ventral, robust, posterioly directed spine; in Hermanella nigra sp. nov.: (1) subgenital plate brown washed with gray, with wide projection near inner base of forceps; (2) penis lobe with a distomedial membranous projection and ventral, robust, posteriorly directed spine; in Hylister obliquus sp. nov.: (1) subgenital plate yellowish brown, with pointed projection near inner base of forceps; (2) penis lobe with ventral, short, narrow, posteromedially directed spine; in Traverella insolita sp. nov.: (1) subgenital plate strongly projected posteriorly, forming three broad and short projections; (2) penis lobe laterally sinuous and apically rounded, with a ventral, long, narrow spine curved toward the midline of the body. Modified keys of male imagos are provided for the three genera, whereas comments regarding their taxonomy are presented. Additionally, Hermanella mazama (Nascimento, Mariano & Salles 2012 in Lima et al. 2012), comb. nov., is proposed.

  4. Temperate mountain forest biodiversity under climate change: compensating negative effects by increasing structural complexity

    National Research Council Canada - National Science Library

    Braunisch, Veronika; Coppes, Joy; Arlettaz, Raphaël; Suchant, Rudi; Zellweger, Florian; Bollmann, Kurt

    2014-01-01

    .... In mountain forests, where vertebrate species largely depend on vegetation composition and structure, deteriorating habitat suitability may thus be mitigated or even compensated by habitat management...

  5. Volatility Properties of Internally- and Externally-Mixed Ambient Aerosols at an Anthropogenically-influenced Forest Site in Southeastern USA

    Science.gov (United States)

    Khlystov, A.; Subramanian, R.

    2015-12-01

    Secondary organic aerosol (SOA) from biogenic sources has a significant contribution to ambient aerosol loadings in Southeastern USA and thus contributes to adverse health effects of air pollution and influences regional and global climate. Volatility properties of biogenic SOA determine its concentration, reactivity, and lifetime, but are still largely unknown. As part of a larger study to assess the effect of biogenic SOA on aerosol optical properties, a set of instruments, including scanning mobility sizers (SMPS), single particle soot photometer (SP2), and a thermodenuder, was deployed during June 2015 at a Duke Forest site near Chapel Hill, NC. The site is characterized by a significant contribution of both biogenic and urban (mostly traffic) sources. Measurements of changes in aerosol volume and optical size upon heating in the thermodenuder at different temperatures are used to derive volatility properties of the ambient aerosol. A limited set of experiments was carried out using the tandem differential mobility analysis (TDMA) approach to investigate whether the ambient aerosol at the Duke Forest site is internally mixed with respect to its volatility properties. In this presentation we will discuss equilibrium and kinetic aspects of aerosol volatility observed during this study and implications of external vs. internal mixing for derivation of bulk volatility properties of ambient aerosol.

  6. Post-fire transformation of the microbial complexes in soils of larch forests in the lower Angara River region

    Science.gov (United States)

    Bogorodskaya, A. V.; Ivanova, G. A.; Tarasov, P. A.

    2011-01-01

    The postfire transformation of the functional activity of the microbial cenoses and the main soil properties under mixed larch forests were studied in the lower reaches of the Angara River. It was shown that the intensity of the postfire changes in the population density, biomass, and activity of the microorganisms in the dark podzolized brown forest soil depended on the degree of burning of the ground cover and the surface litter during the fire. The maximum effects of the fire on the microbial cenoses were observed in the litter and the upper 5-cm-thick layer of the dark-humus horizon in the areas of intense burning. The postfire restoration of the structural-functional activity of the microbial cenoses was determined by the degree of transformation of soil properties and by the postpyrogenic succession in the ground cover. The microbial complexes of the dark podzolized brown forest soils under mixed larch forests in the studied region restored their functional activity after the fires of different intensities quicker than the microbial cenoses of the sandy podzols in the pyrogenic lichen-green-moss pine forests of the same zone.

  7. Towards understanding household-level forest reliance in Cambodia - study sites, methods, and preliminary findings

    DEFF Research Database (Denmark)

    Ra, Koy; Pichdara, Lonn; Dararath, Yem

    There is growing international interest in the role of forests in poverty prevention and reduction. In consequence, this broad area of investigation has been subject to increased research; one major international research project is that facilitated by the Poverty Environment Network (PEN...

  8. Characteristics of a long-term forest soil productivity research site in Missouri

    Science.gov (United States)

    Felix, Jr. Ponder; Nancy M. Mikkelson

    1995-01-01

    Problems with soil quality and maintenance of soil productivity occur when management activities are improperly planned and carried out. To ensure that Forest Service management practices do not reduce long-term soil productivity (LTSP), a network of coordinated long-term experiments is being established across the United States. The first LTSP study in the Central...

  9. Planted Black Walnut Does Well on Cleared Forest Sites -- if Competition is Controlled

    Science.gov (United States)

    John E. Krajicek

    1975-01-01

    After seven growing seasons, survival of black walnut seedlings planted in cleared forest openings did not differ by competition control treatments. The trees grew somewhat larger where all competing vegetation was controlled but almost as large where only herbaceous competition was controlled. Controlling only woody vegetation was no better than no control of any...

  10. The influence of site factors on nitrogen mineralization in forest soils ...

    African Journals Online (AJOL)

    These models are suitable for incorporation into existing plantation decision support systems. The significance of the response in tree growth, following fertilization with N in existing mid-rotation forest nutrition trials, was evaluated against the predictions of N mineralization using the proposed models. An inverse linear ...

  11. How does litter quality and site heterogeneity interact on decomposer food webs of a semi-natural forest?

    DEFF Research Database (Denmark)

    Strandmark, Lisa Bjørnlund; Christensen, Søren

    2005-01-01

    in gaps. Taxonomic diversity of nematodes increased during decomposition and functional diversity of nematodes followed a pattern often encountered, i.e. opportunistic bacterial-feeders were gradually replaced by fungal-feeders and slower growing bacterial-feeders while predators and omnivors peaked......The relative importance of litter quality and site heterogeneity on population dynamics of decomposer food webs was investigated in a semi-natural mixed deciduous forest in Denmark. Litterbags containing beech or ash leaves were placed in four plots. Plots were located within gaps and under closed...

  12. Long-term monitoring of soil microbiological activities in two forest sites in South tyrol in the italian alps.

    Science.gov (United States)

    Margesin, Rosa; Minerbi, Stefano; Schinner, Franz

    2014-09-17

    We monitored microbiological properties in two forest sites over a period of 17 years (1993-2010) within the International Cooperative Programme on Integrated Monitoring of Air Pollution Effects on Ecosystems (ICP IM). The two study sites were located in South Tyrol in the Italian Alps at altitudes of 1,737 m a.s.l. (subalpine site IT01) and 570 m a.s.l. (submontane site IT02). Soil samples were collected in the late spring and autumn of 1993, 2000, and 2010, and were characterized by measuring respiration, key enzyme activities involved in the C, N, P, and S cycles and litter degradation, and the abundance of viable bacterial and fungal populations. Over the study period, an increase in mean annual air temperatures at both sites (+0.6°C and +0.8°C at IT01 and IT02, respectively) was calculated from trendlines. Significantly lower mean annual air temperatures, higher temperature fluctuations, and higher annual precipitation rates were observed at site IT01 than at site IT02. Subalpine site IT01 was characterized by significantly lower microbial activity (respiration, enzymes) and abundance than those at submontane site IT02. The year of sampling had a significant effect on all the parameters investigated, except for nitrification. Fungal abundance decreased consistently over the study period, while no consistent trend was noted among the other parameters investigated. Season only affected a few of the measured microbiological parameters: respiration and bacterial numbers were significantly higher in the spring than in the autumn, while the opposite was noted for xylanase and phosphatase activities. Soil fungi contributed essentially to xylanase and protease activities, while soil bacteria were mainly involved in degradation processes that required the activity of sulfatase.

  13. Atmospheric deposition of trace elements at urban and forest sites in central Poland - Insight into seasonal variability and sources

    Science.gov (United States)

    Siudek, Patrycja; Frankowski, Marcin

    2017-12-01

    This paper includes the results of chemical composition of bulk deposition samples collected simultaneously at urban (Poznań city) and forest (Jeziory) sites in central Poland, between April 2013 and October 2014. Rainwater samples were analyzed for trace elements (As, Zn, Ni, Pb, Cu, Cr, Cd) and physicochemical parameters. Overall, three metals, i.e. Zn, Pb and Cu were the most abundant anthropogenic constituents of rainwater samples from both locations. In Poznań city, the rainwater concentrations of trace elements did not differ significantly between spring and summer. However, they were elevated and more variable during the cold season (fall and winter), suggesting strong contribution from local high-temperature processes related to coal combustion (commercial and residential sector). In contrast to the urban site, relatively low variability in concentrations was found for Cu, Ni, Zn at the forest site, where direct impact of emission from vehicle traffic and coal-fired combustion (power plants) was much lower. The bulk deposition fluxes of Ni, As, Pb and Zn at this site exhibited a clear trend, with higher values during the cold season (fall and winter) than in spring and summer. At the urban site, the sums of total bulk deposition fluxes of Zn, Cu, Pb, Ni, As, Cr, Cd were as follows: 8460.4, 4209.2, 2247.4, 1882.1, 606.6, 281.6 and 31.4 μg m- 2. In addition, during the winter season, a significantly higher deposition fluxes of Cu and Zn were observed for rain (on average 103.8 and 129.4 μg m- 2, respectively) as compared to snow (19.7 μg Cu m- 2 and 54.1 μg Zn m- 2). This suggests that different deposition pattern of trace elements for rain, mixed and snow was probably the effect of several factors: precipitation type, changes in emission and favorable meteorological situation during rain events.

  14. Complex terrain alters temperature and moisture limitations of forest soil respiration across a semiarid to subalpine gradient

    Science.gov (United States)

    Berryman, Erin Michele; Barnard, H.R.; Adams, H.R.; Burns, M.A.; Gallo, E.; Brooks, P.D.

    2015-01-01

    Forest soil respiration is a major carbon (C) flux that is characterized by significant variability in space and time. We quantified growing season soil respiration during both a drought year and a nondrought year across a complex landscape to identify how landscape and climate interact to control soil respiration. We asked the following questions: (1) How does soil respiration vary across the catchments due to terrain-induced variability in moisture availability and temperature? (2) Does the relative importance of moisture versus temperature limitation of respiration vary across space and time? And (3) what terrain elements are important for dictating the pattern of soil respiration and its controls? Moisture superseded temperature in explaining watershed respiration patterns, with wetter yet cooler areas higher up and on north facing slopes yielding greater soil respiration than lower and south facing areas. Wetter subalpine forests had reduced moisture limitation in favor of greater seasonal temperature limitation, and the reverse was true for low-elevation semiarid forests. Coincident climate poorly predicted soil respiration in the montane transition zone; however, antecedent precipitation from the prior 10 days provided additional explanatory power. A seasonal trend in respiration remained after accounting for microclimate effects, suggesting that local climate alone may not adequately predict seasonal variability in soil respiration in montane forests. Soil respiration climate controls were more strongly related to topography during the drought year highlighting the importance of landscape complexity in ecosystem response to drought.

  15. Quantifying the Role of Cloud Water in the Hydrology of Two Montane Forest Sites on East Maui, Hawaii

    Science.gov (United States)

    Scholl, M. A.; Gingerich, S. B.; Giambelluca, T. W.; Nullet, M. A.; Loope, L. L.

    2003-12-01

    East Maui (Haleakala volcano) rises 3054 m above the ocean, and clouds intercepting the mountain slopes are an integral part of the climate. To what extent do the trees and shrubs on the mountainsides extract cloud water that contributes to soil moisture, groundwater recharge, and stream flow in the watersheds? Two sites, on the windward and leeward sides of the mountain, were instrumented to study this process. Weather stations at each site measured climate parameters, and stable isotopes of fog, rain, soil water, stream flow and tree sap were measured monthly to track the proportion of cloud water in the forest hydrologic system. When clouds envelop a forest, the precipitation ranges from light mist to rain, leading to difficulties in measuring cloud water as opposed to rainfall. Deposition of cloud water depends on wind speed, droplet size, surface area of the vegetation, and many other factors. Cloud water deposition was measured on a continual basis using a vertical screen collector, which did not exclude rainfall. The fog isotope collectors did exclude vertically falling rain, and cumulative monthly fog volumes were compared with volumes from isotope rain collectors. Throughfall collectors provided information on the efficiency of the vegetation in collecting cloud water (fog drip). At the windward site, fog screen/ rain gage volume ratios normalized to collection area ranged from 0.74-4.9, with a median value of 1.5. The median fog/ rain ratio from the isotope collectors (normalized to surface area) was 0.35. The screen collector cannot be directly extrapolated to forest canopy, but the data suggest substantial impaction of cloud water on vegetation surfaces exposed to the wind. Isotopic composition of stream water reflected recent precipitation, including cloud water, while the soil water had a larger proportion of precipitation from large rainstorms. Metrosideros polymorpha tree sap isotopic composition was sometimes identical to fog drip, almost never

  16. Examining conifer canopy structural complexity across forest ages and elevations with LiDAR data

    Science.gov (United States)

    Van R. Kane; Jonathan D. Bakker; Robert J. McGaughey; James A. Lutz; Rolf F. Gersonde; Jerry F. Franklin

    2010-01-01

    LiDAR measurements of canopy structure can be used to classify forest stands into structural stages to study spatial patterns of canopy structure, identify habitat, or plan management actions. A key assumption in this process is that differences in canopy structure based on forest age and elevation are consistent with predictions from models of stand development. Three...

  17. Nitrogen and Carbon Biogeochemistry in Forest Sites along an Indirect Urban–Rural Gradient in Southeastern Michigan

    Directory of Open Access Journals (Sweden)

    Ari Y. Kahan

    2014-04-01

    Full Text Available To evaluate the impacts of urbanization on soil and vegetation in protected forest areas, 12 forest sites in Southeastern Michigan USA were studied in an indirect urban–rural gradient. Field study plots were established in forest edge zones of each protected area. Significant findings were that in these edge zones of protected areas: (a soil nitrogen tended to be greater where surrounding housing density was greater; (b overstory woody biomass and basal area were greater where surrounding housing density was greater; and (c the study region overall exhibited low soil carbon content (mean 2.71% and relatively high soil nitrogen content (mean 0.20%, yielding a surprisingly low surface soil C/N ratio (mean 13.4. Overall, 24 woody plant genera were encountered, with the three genera Acer, Carya and Quercus accounting for 83.7% of total biomass and 74.1% of total basal area. No significant relationships were observed between housing density and soil C/N ratio or between housing density and foliar N. Results indicate that a halo of urban-ecological impacts exists in the landscape of Southeastern Michigan, similar to previously studied linear urban–rural gradients in other regions.

  18. Annual variation in canopy openness, air temperature and humidity inthe understory of three forested sites in southern Bahia State, Brazil

    Directory of Open Access Journals (Sweden)

    Marayana Prado Pinheiro

    2013-01-01

    Full Text Available Aiming at contributing to the knowledge of physical factors affecting community structure in Atlantic Forest remnants of southern Bahia state, Brazil, we analyzed the annual variation in the understory microclimate of a hillside forest fragment in the ‘Reserva Particular do Patrimônio Natural Serra do Teimoso’ (RST and a rustic cacao agroforestry system (Cabruca, located nearby the RST. Canopy openness (CO, air temperature (Ta, air relative humidity (RH and vapor pressure deficit (VPD data were collected between April, 2005 and April, 2006 at the base (RSTB, 340 m and the top (RSTT, 640 m of the RST and at the Cabruca (CB, 250 m. Data of rainfall, Ta, RH and VPD were also collected in an open area (OA, 270 m. The highest rainfalls (> 100 mm occurred in November, 2005 and April, 2006, whereas October, 2005 was the driest month (< 20 mm. CO ranged between 2.5 % in the CB (April, 2006 and 7.7 % in the RST (October, 2005. Low rainfall in October, 2005 affected VPDmax in all sites. Those effects were more pronounced in OA, followed by CB, RSTB and RSTT. During the period of measurements, the values of Ta, RH and VPD in CB were closer to the values measured in OA than to the values measured inside the forest.

  19. Forest-atmosphere BVOC exchange in diverse and structurally complex canopies: 1-D modeling of a mid-successional forest in northern Michigan

    Energy Technology Data Exchange (ETDEWEB)

    Bryan, Alexander M.; Cheng, Susan J.; Ashworth, Kirsti; Guenther, Alex B.; Hardiman, Brady; Bohrer, Gil; Steiner, A. L.

    2015-11-01

    Foliar emissions of biogenic volatile organic compounds (BVOC)dimportant precursors of tropospheric ozone and secondary organic aerosolsdvary widely by vegetation type. Modeling studies to date typi-cally represent the canopy as a single dominant tree type or a blend of tree types, yet many forests are diverse with trees of varying height. To assess the sensitivity of biogenic emissions to tree height vari-ation, we compare two 1-D canopy model simulations in which BVOC emission potentials are homo-geneous or heterogeneous with canopy depth. The heterogeneous canopy emulates the mid-successional forest at the University of Michigan Biological Station (UMBS). In this case, high-isoprene-emitting fo-liage (e.g., aspen and oak) is constrained to the upper canopy, where higher sunlight availability increases the light-dependent isoprene emission, leading to 34% more isoprene and its oxidation products as compared to the homogeneous simulation. Isoprene declines from aspen mortality are 10% larger when heterogeneity is considered. Overall, our results highlight the importance of adequately representing complexities of forest canopy structure when simulating light-dependent BVOC emissions and chemistry.

  20. Forest-atmosphere BVOC exchange in diverse and structurally complex canopies: 1-D modeling of a mid-successional forest in northern Michigan

    Science.gov (United States)

    Bryan, Alexander M.; Cheng, Susan J.; Ashworth, Kirsti; Guenther, Alex B.; Hardiman, Brady S.; Bohrer, Gil; Steiner, Allison L.

    2015-11-01

    Foliar emissions of biogenic volatile organic compounds (BVOC)-important precursors of tropospheric ozone and secondary organic aerosols-vary widely by vegetation type. Modeling studies to date typically represent the canopy as a single dominant tree type or a blend of tree types, yet many forests are diverse with trees of varying height. To assess the sensitivity of biogenic emissions to tree height variation, we compare two 1-D canopy model simulations in which BVOC emission potentials are homogeneous or heterogeneous with canopy depth. The heterogeneous canopy emulates the mid-successional forest at the University of Michigan Biological Station (UMBS). In this case, high-isoprene-emitting foliage (e.g., aspen and oak) is constrained to the upper canopy, where higher sunlight availability increases the light-dependent isoprene emission, leading to 34% more isoprene and its oxidation products as compared to the homogeneous simulation. Isoprene declines from aspen mortality are 10% larger when heterogeneity is considered. Overall, our results highlight the importance of adequately representing complexities of forest canopy structure when simulating light-dependent BVOC emissions and chemistry.

  1. Deep phylogeographic divergence of a migratory passerine in Sino-Himalayan and Siberian forests: the Red-flanked Bluetail (Tarsiger cyanurus) complex

    Science.gov (United States)

    Luo, Site; Wu, Yuchun; Chang, Qing; Liu, Yang; Yang, Xiaojun; Zhang, Zhengwang; Zhang, Min; Zhang, Qiang; Zou, Fasheng

    2014-01-01

    Enormous mountainous forests in Sino-Himalayans and Siberia harbor important avian biodiversity in the Northern Hemisphere. Numerous studies in last two decades have been contributed to systematics and taxonomy of passerines birds in these regions and have revealed various and complex phylogeographic patterns. A passerine species Red-flanked Bluetail Tarsiger cyanurus provided a good system to manifest such evolutionary complexity. The subspecies T. c. cyanurus and T. c. rufilatus (or/and T. c. pallidior), divergent in morphology, acoustics, and migratory strategies are allopatric in Siberia and Sino-Himalayan forests, respectively. The two taxa most likely deserve full species status but rigorous genetic analysis is missing. In this study, multilocus phylogeography based on mitochondrial DNA and Z-linked DNA reveals that T. c. cyanurus and T. c. rufilatus are reciprocally monophyletic with significant statistical support and differ with a large number of diagnostic nucleotide sites resulting substantial genetic divergence. Our finding supports the proposed split of Tarsiger cyanurus s.l. that T. cyanurus and T. rufilatus should be treated as two full species. Whether “pallidior” is a subspecies or geographical form of T. rufilatus is still uncertain. Additionally, these two forest passerine species may have diverged 1.88 (3.25–1.30) Mya, which might be shaped by geographical vicariance due to grassland and desert steppe on the central Loess Plateau during the Pliocene. Taken together, this study and further suggests another independent example of North Palearctic–Sino-Himalayan phylogeographic pattern in Palearctic birds. PMID:24772276

  2. A Historical Evaluation of the U15 Complex, Nevada National Security Site, Nye County, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Drollinger, Harold [Desert Research Inst., Nevada University, Reno, NV (United States); Holz, Barbara A. [Desert Research Inst., Nevada University, Reno, NV (United States); Bullard, Thomas F. [Desert Research Inst., Nevada University, Reno, NV (United States); Goldenberg, Nancy G. [Desert Research Inst., Nevada University, Reno, NV (United States); Ashbaugh, Laurence J. [Desert Research Inst., Nevada University, Reno, NV (United States); Griffin, Wayne R. [Desert Research Inst., Nevada University, Reno, NV (United States)

    2014-01-01

    This report presents a historical evaluation of the U15 Complex on the Nevada National Security Site (NNSS) in southern Nevada. The work was conducted by the Desert Research Institute at the request of the U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office and the U.S. Department of Defense, Defense Threat Reduction Agency. Three underground nuclear tests and two underground nuclear fuel storage experiments were conducted at the complex. The nuclear tests were Hard Hat in 1962, Tiny Tot in 1965, and Pile Driver in 1966. The Hard Hat and Pile Driver nuclear tests involved different types of experiment sections in test drifts at various distances from the explosion in order to determine which sections could best survive in order to design underground command centers. The Tiny Tot nuclear test involved an underground cavity in which the nuclear test was executed. It also provided data in designing underground structures and facilities to withstand a nuclear attack. The underground nuclear fuel storage experiments were Heater Test 1 from 1977 to 1978 and Spent Fuel Test - Climax from 1978 to 1985. Heater Test 1 was used to design the later Spent Fuel Test - Climax experiment. The latter experiment was a model of a larger underground storage facility and primarily involved recording the conditions of the spent fuel and the surrounding granite medium. Fieldwork was performed intermittently in the summers of 2011 and 2013, totaling 17 days. Access to the underground tunnel complex is sealed and unavailable. Restricted to the surface, four buildings, four structures, and 92 features associated with nuclear testing and fuel storage experiment activities at the U15 Complex have been recorded. Most of these are along the west side of the complex and next to the primary access road and are characteristic of an industrial mining site, albeit one with scientific interests. The geomorphological fieldwork was conducted over three days in the

  3. A Historical Evaluation of the U15 Complex, Nevada National Security Site, Nye County, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Drollinger, Harold [Desert Research Inst., Nevada University, Reno, NV (United States); Holz, Barbara A. [Desert Research Inst., Nevada University, Reno, NV (United States); Bullard, Thomas F. [Desert Research Inst., Nevada University, Reno, NV (United States); Goldenberg, Nancy G. [Desert Research Inst., Nevada University, Reno, NV (United States); Ashbaugh, Laurence J. [Desert Research Inst., Nevada University, Reno, NV (United States); Griffin, Wayne R. [Desert Research Inst., Nevada University, Reno, NV (United States)

    2014-01-09

    This report presents a historical evaluation of the U15 Complex on the Nevada National Security Site (NNSS) in southern Nevada. The work was conducted by the Desert Research Institute at the request of the U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office and the U.S. Department of Defense, Defense Threat Reduction Agency. Three underground nuclear tests and two underground nuclear fuel storage experiments were conducted at the complex. The nuclear tests were Hard Hat in 1962, Tiny Tot in 1965, and Pile Driver in 1966. The Hard Hat and Pile Driver nuclear tests involved different types of experiment sections in test drifts at various distances from the explosion in order to determine which sections could best survive in order to design underground command centers. The Tiny Tot nuclear test involved an underground cavity in which the nuclear test was executed. It also provided data in designing underground structures and facilities to withstand a nuclear attack. The underground nuclear fuel storage experiments were Heater Test 1 from 1977 to 1978 and Spent Fuel Test - Climax from 1978 to 1985. Heater Test 1 was used to design the later Spent Fuel Test - Climax experiment. The latter experiment was a model of a larger underground storage facility and primarily involved recording the conditions of the spent fuel and the surrounding granite medium. Fieldwork was performed intermittently in the summers of 2011 and 2013, totaling 17 days. Access to the underground tunnel complex is sealed and unavailable. Restricted to the surface, four buildings, four structures, and 92 features associated with nuclear testing and fuel storage experiment activities at the U15 Complex have been recorded. Most of these are along the west side of the complex and next to the primary access road and are characteristic of an industrial mining site, albeit one with scientific interests. The geomorphological fieldwork was conducted over three days in the

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

    Science.gov (United States)

    Fotis, Alexander T; Curtis, Peter S

    2017-10-01

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

  5. Influence of stocking, site quality, stand age, low-severity canopy disturbance, and forest composition on sub-boreal aspen mixedwood carbon stocks

    Science.gov (United States)

    Reinikainen, Michael; D’Amato, Anthony W.; Bradford, John B.; Fraver, Shawn

    2014-01-01

    Low-severity canopy disturbance presumably influences forest carbon dynamics during the course of stand development, yet the topic has received relatively little attention. This is surprising because of the frequent occurrence of such events and the potential for both the severity and frequency of disturbances to increase as a result of climate change. We investigated the impacts of low-severity canopy disturbance and average insect defoliation on forest carbon stocks and rates of carbon sequestration in mature aspen mixedwood forests of varying stand age (ranging from 61 to 85 years), overstory composition, stocking level, and site quality. Stocking level and site quality positively affected the average annual aboveground tree carbon increment (CAAI), while stocking level, site quality, and stand age positively affected tree carbon stocks (CTREE) and total ecosystem carbon stocks (CTOTAL). Cumulative canopy disturbance (DIST) was reconstructed using dendroecological methods over a 29-year period. DIST was negatively and significantly related to soil carbon (CSOIL), and it was negatively, albeit marginally, related to CTOTAL. Minima in the annual aboveground carbon increment of trees (CAI) occurred at sites during defoliation of aspen (Populus tremuloides Michx.) by forest tent caterpillar (Malacosoma disstria Hubner), and minima were more extreme at sites dominated by trembling aspen than sites mixed with conifers. At sites defoliated by forest tent caterpillar in the early 2000s, increased sequestration by the softwood component (Abies balsamea (L.) Mill. and Picea glauca (Moench) Voss) compensated for overall decreases in CAI by 17% on average. These results underscore the importance of accounting for low-severity canopy disturbance events when developing regional forest carbon models and argue for the restoration and maintenance of historically important conifer species within aspen mixedwoods to enhance stand-level resilience to disturbance agents and maintain

  6. A comparison of winter mercury accumulation at forested and no-canopy sites measured with different snow sampling techniques

    Science.gov (United States)

    Nelson, S.J.; Johnson, K.B.; Weathers, K.C.; Loftin, C.S.; Fernandez, I.J.; Kahl, J.S.; Krabbenhoft, D.P.

    2008-01-01

    Atmospheric mercury (Hg) is delivered to ecosystems via rain, snow, cloud/fog, and dry deposition. The importance of snow, especially snow that has passed through the forest canopy (throughfall), in delivering Hg to terrestrial ecosystems has received little attention in the literature. The snowpack is a dynamic system that links atmospheric deposition and ecosystem cycling through deposition and emission of deposited Hg. To examine the magnitude of Hg delivery via snowfall, and to illuminate processes affecting Hg flux to catchments during winter (cold season), Hg in snow in no-canopy areas and under forest canopies measured with four collection methods were compared: (1) Hg in wet precipitation as measured by the Mercury Deposition Network (MDN) for the site in Acadia National Park, Maine, USA, (2) event throughfall (collected after snowfall cessation for accumulations of >8 cm), (3) season-long throughfall collected using the same apparatus for event sampling but deployed for the entire cold season, and (4) snowpack sampling. Estimates (mean ?? SE) of Hg deposition using these methods during the 91-day cold season in 2004-2005 at conifer sites showed that season-long throughfall Hg flux (1.80 ??g/m2) < snowpack Hg (2.38 ?? 0.68 ??g/m2) < event throughfall flux (5.63 ?? 0.38 ??g/m2). Mercury deposition at the MDN site (0.91 ??g/m2) was similar to that measured at other no-canopy sites in the area using the other methods, but was 3.4 times less than was measured under conifer canopies using the event sampling regime. This indicates that snow accumulated under the forest canopy received Hg from the overstory or exhibited less re-emission of Hg deposited in snow relative to open areas. The soil surface of field-scale plots were sprayed with a natural rain water sample that contained an Hg tracer (202Hg) just prior to the first snowfall to explore whether some snowpack Hg might be explained from soil emissions. The appearance of the 202Hg tracer in the snowpack (0

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

    Science.gov (United States)

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

    2015-02-01

    Global change is impacting forests worldwide, threatening biodiversity and ecosystem services including climate regulation. Understanding how forests respond is critical to forest conservation and climate protection. This review describes an international network of 59 long-term forest dynamics research sites (CTFS-ForestGEO) useful for characterizing forest responses to global change. Within very large plots (median size 25 ha), all stems ≥ 1 cm diameter are identified to species, mapped, and regularly recensused according to standardized protocols. CTFS-ForestGEO spans 25 °S-61 °N latitude, is generally representative of the range of bioclimatic, edaphic, and topographic conditions experienced by forests worldwide, and is the only forest monitoring network that applies a standardized protocol to each of the world's major forest biomes. Supplementary standardized measurements at subsets of the sites provide additional information on plants, animals, and ecosystem and environmental variables. CTFS-ForestGEO sites are experiencing multifaceted anthropogenic global change pressures including warming (average 0.61 °C), changes in precipitation (up to ± 30% change), atmospheric deposition of nitrogen and sulfur compounds (up to 3.8 g N m(-2) yr(-1) and 3.1 g S m(-2) yr(-1)), and forest fragmentation in the surrounding landscape (up to 88% reduced tree cover within 5 km). The broad suite of measurements made at CTFS-ForestGEO sites makes it possible to investigate the complex ways in which global change is impacting forest dynamics. Ongoing research across the CTFS-ForestGEO network is yielding insights into how and why the forests are changing, and continued monitoring will provide vital contributions to understanding worldwide forest diversity and dynamics in an era of global change. © 2014 John Wiley & Sons Ltd.

  8. The Speulderbos fiducial reference site for continuous monitoring of forest biophysical variables

    NARCIS (Netherlands)

    Brede, Benjamin; Bartholomeus, Harm; Suomalainen, Juha; Clevers, Jan; Verbesselt, Jan; Herold, Martin; Culvenor, Darius; Gascon, Ferran

    2016-01-01

    This contribution describes the Speulderbos fiducial reference site for biophysical variables with a focus on foliage variables and Leaf Area Index (LAI). The site implements Unmanned Aerial Vehicle (UAV)- and ground-based sensing systems that aim at high temporal resolution observations to

  9. Understanding global warming impacts to forest and rangeland landscapes with benchmark ecological sites

    Science.gov (United States)

    A benchmark ecological site is one that has the greatest potential to yield data and information about ecological functions, processes, and the effects of management or climate change that can apply to a broad area or critical ecological zone. A benchmark ecological site represents other similar sit...

  10. Stand dynamics, spatial pattern and site quality in Austrocedrus chilensis forests in Patagonia, Argentina

    Directory of Open Access Journals (Sweden)

    S.L. Burns

    2013-07-01

    Full Text Available Aim of study: The objective of this study was to analyze the stand structure and spatial pattern of two A. chilensis stands with contrasting soil conditions and different site qualities in order to explore if these differences lead to patterns similar to the ones observed under different precipitation conditions.Area of study: The study was carried out in two stands located near the city of El Bolsón (41° 56’S - 71° 33’ W, Rio Negro, Argentina.Material and Methods: We evaluated age difference between canopy strata (upper and lower in two stands with different site qualities by means of a Mann-Whitney test. Dead individuals by diameter class were compared by means of a chi square test. Spatial distribution pattern was analyzed using the pair-correlation function and the mark-correlation function.Main results: Both sites exhibited a random spatial distribution of A. chilensis but different processes seem to underlie the patterns. In the low-quality site facilitation and continuous establishment led to a transient clumped spatial pattern. Mortality mediated by competition occurred mainly on small trees resulting in the current random pattern. On the other hand, spatial pattern in the high-quality site does not reflect a facilitation mediated recruitment. The upper strata established synchronously and subsequent regeneration was episodic.Research highlights: The results show that the differences in site quality may lead to different establishment spatial patterns, showing the importance of facilitation processes in sites with drier soil conditions and lower quality, although results may be site specific, due to the lack of replications.Keywords: Spatial analysis; regeneration; mortality; competition; facilitation.Abbreviations used:  LQ: low-quality site; HQ: high-quality site.

  11. Validation of chemical analyses of atmospheric deposition in forested European sites

    Directory of Open Access Journals (Sweden)

    Erwin ULRICH

    2005-08-01

    Full Text Available Within the activities of the Integrated Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests and of the EU Regulation 2152/2003, a Working Group on Quality Assurance/Quality Control of analyses has been created to assist the participating laboratories in the analysis of atmospheric deposition, soil and soil solution, and leaves/needles. As part of the activity of the WG, this study is a statistical analysis in the field of water analysis of chemical concentrations and relationships between ions, and between conductivity and ions for different types of samples (bulk or wet-only samples, throughfall, stemflow considered in forest studies. About 5000 analyses from seven laboratories were used to establish relationships representative of different European geographic and climatic situations, from northern Finland to southern Italy. Statistically significant differences between the relationships obtained from different types of solutions, interacting with different types of vegetation (throughfall and stemflow samples, broad-leaved trees and conifers and with varying influence of marine salt were tested. The ultimate aim is to establish general relationships between ions, and between conductivity and ions, with relative confidence limits, which can be used as a comparison with those established in single laboratories. The use of such techniques is strongly encouraged in the ICPF laboratories to validate single chemical analyses, to be performed when it is still possible to replicate the analysis, and as a general overview of the whole set of analyses, to obtain an indication of the laboratory performance on a long-term basis.

  12. Formation of chloroform in soil. A year-round study at a Danish spruce forest site

    DEFF Research Database (Denmark)

    Haselmann, K.F.; Laturnus, F.; Grøn, C.

    2002-01-01

    Soil air from top soil of a Danish spruce forest was investigated monthly from December 1997 to December 1998 for the occurrence of chloroform, 1,1,1-trichloroethane, tetrachloromethane, trichloroethene and tetrachloroethene. Within the monitoring period, three different patterns of soil air...... concentrations were identified. For chloroform, concentrations peaked in spring and autumn while 1,1,1-trichloroethane and tetrachloromethane peaked during mid winter. Trichloroethene and tetrachloroethene, concentrations remained constant throughout the year. The relative ratios of soil air concentrations...... concentrations were found in the soil in warm and humid periods of the year (spring and autumn) with high microbial activity....

  13. Sleeping site preferences in Sapajus cay Illiger 1815 (Primates: Cebidae) in a disturbed fragment of the Upper Paraná Atlantic Forest, Rancho Laguna Blanca, Eastern Paraguay.

    Science.gov (United States)

    Smith, Rebecca L; Hayes, Sarah E; Smith, Paul; Dickens, Jeremy K

    2017-08-20

    Wild primates can spend up to half of their lives sleeping, during which time they are subjected to many of the same selective pressures that they face when awake. Choosing an appropriate sleeping site can thus have important fitness consequences. We examined the sleeping site preferences of wild hooded capuchins (Sapajus cay) in a small degraded fragment of the Upper Paraná Atlantic Forest at Rancho Laguna Blanca (RLB) in eastern Paraguay. Sleeping trees and sites were identified during 5 months of field observations and their physical characteristics were compared to those of non-sleeping trees and sites. Capuchins preferred larger emergent trees with more main and forked branches, no lianas and denser undergrowth directly below. These were found in sites of more mature forest with fewer small trees, less liana coverage and denser undergrowth but more fruiting trees. The species composition of the sleeping sites differed from that of the non-sleeping sites and was dominated by Albizia niopoides (Mimosaceae) as well as Peltophorum dubium (Fabaceae) and Anadenanthera colubrina (Fabaceae). The capuchins were found to sleep most often in these three tree species: 69.23% in Albizia niopoides (Mimosaceae), 11.54% in Peltophorum dubium (Fabaceae) and 11.54% in Anadenanthera colubrina (Fabaceae). We found evidence for the predator avoidance, thermoregulatory, social contact and feeding site proximity hypotheses. We found no support for parasite avoidance, given the reuse of sites, although the small size of the forest fragment may have restricted this. Their preference for older-growth forest suggests that selective logging impacts hooded capuchins. However, their persistence in a disturbed fragment shows they are highly adaptable, providing support for the value of conservation and reforestation of even small fragments of the Paraguayan Upper Paraná Atlantic Forest.

  14. The chromosomal high-affinity binding sites for the Drosophila dosage compensation complex.

    Directory of Open Access Journals (Sweden)

    Tobias Straub

    2008-12-01

    Full Text Available Dosage compensation in male Drosophila relies on the X chromosome-specific recruitment of a chromatin-modifying machinery, the dosage compensation complex (DCC. The principles that assure selective targeting of the DCC are unknown. According to a prevalent model, X chromosome targeting is initiated by recruitment of the DCC core components, MSL1 and MSL2, to a limited number of so-called "high-affinity sites" (HAS. Only very few such sites are known at the DNA sequence level, which has precluded the definition of DCC targeting principles. Combining RNA interference against DCC subunits, limited crosslinking, and chromatin immunoprecipitation coupled to probing high-resolution DNA microarrays, we identified a set of 131 HAS for MSL1 and MSL2 and confirmed their properties by various means. The HAS sites are distributed all over the X chromosome and are functionally important, since the extent of dosage compensation of a given gene and its proximity to a HAS are positively correlated. The sites are mainly located on non-coding parts of genes and predominantly map to regions that are devoid of nucleosomes. In contrast, the bulk of DCC binding is in coding regions and is marked by histone H3K36 methylation. Within the HAS, repetitive DNA sequences mainly based on GA and CA dinucleotides are enriched. Interestingly, DCC subcomplexes bind a small number of autosomal locations with similar features.

  15. Early impact of alternative thinning approaches on structure diversity and complexity at stand level in two beech forests in Italy

    Directory of Open Access Journals (Sweden)

    Claudia Becagli

    2013-12-01

    Full Text Available Stand structure, tree density as well as tree spatial pattern define natural dynamics and competition process. They are therefore parameters used to define any silvicultural management type. This work aims to report first data resulting from a silvicultural experiment in beech forests. The objective of the trial is testing the structure manipulation in terms of diversity and the reduction of inter-tree competition of different thinning approaches. Alternative thinning methods have been applied in two independent experimental sites located in the pre-Alps and Southern Apennines, in Italy. Specific goals were to: (i verify the impact early after thinning implementation on forest structure through a set of diversity and competition metrics resulting from a literature review; (ii the sensitivity of tested indexes to effectively detect thinning manipulation. Main result show the low sensitivity of stand structure indexes and the ability of competition metrics to detect thinning outcome.

  16. Synthesis, characterization, and reactivity studies of heterodinuclear complexes modeling active sites in purple acid phospatases.

    OpenAIRE

    Jarenmark, Martin; Haukka, Matti; Demeshko, Serhiy; Tuczek, Felix; Zuppiroli, Luca; Meyer, Franc; Nordlander, Ebbe

    2011-01-01

    To model the heterodinuclear active sites in plant purple acid phosphatases, a mononuclear synthon, [Fe(III)(H(2)IPCPMP)(Cl(2))][PF(6)] (1), has been generated in situ from the ligand 2-(N-isopropyl-N-((2-pyridyl)methyl)aminomethyl)-6-(N-(carboxylmethyl)-N-((2-pyridyl)methyl)amino methyl)-4-methylphenol (IPCPMP) and used to synthesize heterodinuclear complexes of the formulas [Fe(III)M(II)(IPCPMP)(OAc)(2)(CH(3)OH)][PF(6)] (M = Zn (2), Co (3), Ni (4), Mn (5)), [Fe(III)Zn(II)(IPCPMP)(mpdp)][PF(...

  17. Strong topographic sheltering effects lead to spatially complex treeline advance and increased forest density in a subtropical mountain region.

    Science.gov (United States)

    Greenwood, Sarah; Chen, Jan-Chang; Chen, Chaur-Tzuhn; Jump, Alistair S

    2014-12-01

    Altitudinal treelines are typically temperature limited such that increasing temperatures linked to global climate change are causing upslope shifts of treelines worldwide. While such elevational increases are readily predicted based on shifting isotherms, at the regional level the realized response is often much more complex, with topography and local environmental conditions playing an important modifying role. Here, we used repeated aerial photographs in combination with forest inventory data to investigate changes in treeline position in the Central Mountain Range of Taiwan over the last 60 years. A highly spatially variable upslope advance of treeline was identified in which topography is a major driver of both treeline form and advance. The changes in treeline position that we observed occurred alongside substantial increases in forest density, and lead to a large increase in overall forest area. These changes will have a significant impact on carbon stocking in the high altitude zone, while the concomitant decrease in alpine grassland area is likely to have negative implications for alpine species. The complex and spatially variable changes that we report highlight the necessity for considering local factors such as topography when attempting to predict species distributional responses to warming climate. © 2014 John Wiley & Sons Ltd.

  18. The state of microbial complexes in soils of forest ecosystems after fires and defoliation of stands by gypsy moths

    Science.gov (United States)

    Bogorodskaya, A. V.; Baranchikov, Yu. N.; Ivanova, G. A.

    2009-03-01

    The state of microbial cenoses in the soils of forest ecosystems damaged by fires of different strengths and gypsy moth outbreaks (Central Siberia) was assessed by the intensity of the basal respiration, the content of carbon of the microbial biomass, and the microbial metabolic quotient. The degree of the disturbance of the microbial cenoses in the soils under pine forests after fires was higher than that in the soils under the forests defoliated by gypsy moths. The greatest changes of the microbial complexes were recorded after the fires of high and medium intensity. In the litters, the content of the microbial biomass, the intensity of basal respiration, and the microbial metabolic quotient value were restored on the fifth year after the fires, whereas in the upper (0-10 cm) soil layer, these parameters still differed from those in the control variant, especially after the highly intense fires. After the weak fires, the ecophysiological state of the microbial complexes was restored within two-three years.

  19. Catalyst recognition of cis-1,2-diols enables site-selective functionalization of complex molecules

    Science.gov (United States)

    Sun, Xixi; Lee, Hyelee; Lee, Sunggi; Tan, Kian L.

    2013-09-01

    Carbohydrates and natural products serve essential roles in nature, and also provide core scaffolds for pharmaceutical agents and vaccines. However, the inherent complexity of these molecules imposes significant synthetic hurdles for their selective functionalization and derivatization. Nature has, in part, addressed these issues by employing enzymes that are able to orient and activate substrates within a chiral pocket, which increases dramatically both the rate and selectivity of organic transformations. In this article we show that similar proximity effects can be utilized in the context of synthetic catalysts to achieve general and predictable site-selective functionalization of complex molecules. Unlike enzymes, our catalysts apply a single reversible covalent bond to recognize and bind to specific functional group displays within substrates. By combining this unique binding selectivity and asymmetric catalysis, we are able to modify the less reactive axial positions within monosaccharides and natural products.

  20. A summary of ecological investigations at the burial ground complex, Savannah River Site - 1994

    Energy Technology Data Exchange (ETDEWEB)

    Friday, G.P.; Hartman, G.D.; Mackey, H.E. Jr.; Riley, R.S.; Roach, J.L.; Specht, W.L.; Westbury, H.M.; Wike, L.D.

    1994-11-01

    This report summarizes the results of three ecological investigations that were conducted in 1994 at the Burial Ground Complex (BGC) at the Savannah River Site (SRS). The three topics of study included remote sensing, aquatic toxicity testing, and qualitative surveys of herpetofauna and small mammals. Interim reports from each investigation are included in the appendices (A, B, and C). The objectives of the remote sensing effort were to compile historical aerial photography of the BGC and to develop a land use/cover map of the complex using recent aerial imagery. The goal of the aquatic toxicity testing was to determine if surface waters were toxic to aquatic biota whereas the objectives of the vertebrate surveys were to identify the species diversity and relative abundances of amphibians, reptiles, and small mammals inhabiting the study area.

  1. Solution structure of the Atg1 complex: implications for the architecture of the phagophore assembly site.

    Science.gov (United States)

    Köfinger, Jürgen; Ragusa, Michael J; Lee, Il-Hyung; Hummer, Gerhard; Hurley, James H

    2015-05-05

    The biogenesis of autophagosomes commences at the phagophore assembly site (PAS), a protein-vesicle ultrastructure that is organized by the Atg1 complex. The Atg1 complex consists of the Atg1 protein kinase, the intrinsically disordered region-rich Atg13, and the dimeric double crescent-shaped Atg17-Atg31-Atg29 subcomplex. We show that the PAS contains a relatively uniform ∼28 copies of Atg17, and upon autophagy induction, similar numbers of Atg1 and Atg13 molecules. We then apply ensemble refinement of small-angle X-ray scattering to determine the solution structures of the Atg1-Atg13 and Atg17-Atg31-Atg29 subcomplexes and the Atg1 complex, using a trimmed minipentamer tractable to biophysical studies. We observe tetramers of Atg1 pentamers that assemble via Atg17-Atg31-Atg29. This leads to a model for the higher organization of the Atg1 complex in PAS scaffolding. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. NPP Temperate Forest: OTTER Project Sites, Oregon, USA, 1989-1991, R1

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set provides net primary productivity (NPP) estimates and associated field measurements for six sites located along the 250-km, west-east transect of the...

  3. Simple proxies for estimating the concentrations of monoterpenes and their oxidation products at a boreal forest site

    Directory of Open Access Journals (Sweden)

    J. Kontkanen

    2016-10-01

    Full Text Available The oxidation products of monoterpenes likely have a crucial role in the formation and growth of aerosol particles in boreal forests. However, the continuous measurements of monoterpene concentrations are usually not available on decadal timescales, and the direct measurements of the concentrations of monoterpene oxidation product have so far been scarce. In this study we developed proxies for the concentrations of monoterpenes and their oxidation products at a boreal forest site in Hyytiälä, southern Finland. For deriving the proxies we used the monoterpene concentration measured with a proton transfer reaction mass spectrometer (PTR-MS during 2006–2013. Our proxies for the monoterpene concentration take into account the temperature-controlled emissions from the forest ecosystem, the dilution caused by the mixing within the boundary layer and different oxidation processes. All the versions of our proxies captured the seasonal variation of the monoterpene concentration, the typical proxy-to-measurements ratios being between 0.8 and 1.3 in summer and between 0.6 and 2.6 in winter. In addition, the proxies were able to describe the diurnal variation of the monoterpene concentration rather well, especially in summer months. By utilizing one of the proxies, we calculated the concentration of oxidation products of monoterpenes by considering their production in the oxidation and their loss due to condensation on aerosol particles. The concentration of oxidation products was found to have a clear seasonal cycle, with a maximum in summer and a minimum in winter. The concentration of oxidation products was lowest in the morning or around noon and highest in the evening. In the future, our proxies for the monoterpene concentration and their oxidation products can be used, for example, in the analysis of new particle formation and growth in boreal environments.

  4. Airborne lidar-based estimates of tropical forest structure in complex terrain: opportunities and trade-offs for REDD+

    Science.gov (United States)

    Leitold, Veronika; Keller, Michael; Morton, Douglas C; Cook, Bruce D; Shimabukuro, Yosio E

    2015-12-01

    Carbon stocks and fluxes in tropical forests remain large sources of uncertainty in the global carbon budget. Airborne lidar remote sensing is a powerful tool for estimating aboveground biomass, provided that lidar measurements penetrate dense forest vegetation to generate accurate estimates of surface topography and canopy heights. Tropical forest areas with complex topography present a challenge for lidar remote sensing. We compared digital terrain models (DTM) derived from airborne lidar data from a mountainous region of the Atlantic Forest in Brazil to 35 ground control points measured with survey grade GNSS receivers. The terrain model generated from full-density (~20 returns m-2) data was highly accurate (mean signed error of 0.19 ± 0.97 m), while those derived from reduced-density datasets (8 m-2, 4 m-2, 2 m-2 and 1 m-2) were increasingly less accurate. Canopy heights calculated from reduced-density lidar data declined as data density decreased due to the inability to accurately model the terrain surface. For lidar return densities below 4 m-2, the bias in height estimates translated into errors of 80-125 Mg ha-1 in predicted aboveground biomass. Given the growing emphasis on the use of airborne lidar for forest management, carbon monitoring, and conservation efforts, the results of this study highlight the importance of careful survey planning and consistent sampling for accurate quantification of aboveground biomass stocks and dynamics. Approaches that rely primarily on canopy height to estimate aboveground biomass are sensitive to DTM errors from variability in lidar sampling density.

  5. Airborne Lidar-Based Estimates of Tropical Forest Structure in Complex Terrain: Opportunities and Trade-Offs for REDD+

    Science.gov (United States)

    Leitold, Veronika; Keller, Michael; Morton, Douglas C.; Cook, Bruce D.; Shimabukuro, Yosio E.

    2015-01-01

    Background: Carbon stocks and fluxes in tropical forests remain large sources of uncertainty in the global carbon budget. Airborne lidar remote sensing is a powerful tool for estimating aboveground biomass, provided that lidar measurements penetrate dense forest vegetation to generate accurate estimates of surface topography and canopy heights. Tropical forest areas with complex topography present a challenge for lidar remote sensing. Results: We compared digital terrain models (DTM) derived from airborne lidar data from a mountainous region of the Atlantic Forest in Brazil to 35 ground control points measured with survey grade GNSS receivers. The terrain model generated from full-density (approx. 20 returns/sq m) data was highly accurate (mean signed error of 0.19 +/-0.97 m), while those derived from reduced-density datasets (8/sq m, 4/sq m, 2/sq m and 1/sq m) were increasingly less accurate. Canopy heights calculated from reduced-density lidar data declined as data density decreased due to the inability to accurately model the terrain surface. For lidar return densities below 4/sq m, the bias in height estimates translated into errors of 80-125 Mg/ha in predicted aboveground biomass. Conclusions: Given the growing emphasis on the use of airborne lidar for forest management, carbon monitoring, and conservation efforts, the results of this study highlight the importance of careful survey planning and consistent sampling for accurate quantification of aboveground biomass stocks and dynamics. Approaches that rely primarily on canopy height to estimate aboveground biomass are sensitive to DTM errors from variability in lidar sampling density.

  6. Recycled Uranium Mass Balance Project Y-12 National Security Complex Site Report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-12-01

    This report has been prepared to summarize the findings of the Y-12 National Security Complex (Y-12 Complex) Mass Balance Project and to support preparation of associated U. S. Department of Energy (DOE) site reports. The project was conducted in support of DOE efforts to assess the potential for health and environmental issues resulting from the presence of transuranic (TRU) elements and fission products in recycled uranium (RU) processed by DOE and its predecessor agencies. The United States government used uranium in fission reactors to produce plutonium and tritium for nuclear weapons production. Because uranium was considered scarce relative to demand when these operations began almost 50 years ago, the spent fuel from U.S. fission reactors was processed to recover uranium for recycling. The estimated mass balance for highly enriched RU, which is of most concern for worker exposure and is the primary focus of this project, is summarized in a table. A discrepancy in the mass balance between receipts and shipments (plus inventory and waste) reflects an inability to precisely distinguish between RU and non-RU shipments and receipts involving the Y-12 Complex and Savannah River. Shipments of fresh fuel (non-RU) and sweetener (also non-RU) were made from the Y-12 Complex to Savannah River along with RU shipments. The only way to distinguish between these RU and non-RU streams using available records is by enrichment level. Shipments of {le}90% enrichment were assumed to be RU. Shipments of >90% enrichment were assumed to be non-RU fresh fuel or sweetener. This methodology using enrichment level to distinguish between RU and non-RU results in good estimates of RU flows that are reasonably consistent with Savannah River estimates. Although this is the best available means of distinguishing RU streams, this method does leave a difference of approximately 17.3 MTU between receipts and shipments. Slightly depleted RU streams received by the Y-12 Complex from ORGDP and

  7. Non-timber Forest Products, Their Vulnerability and Conservation in a Designated UNESCO Heritage Site of Arunanchal Pradesh, India

    Directory of Open Access Journals (Sweden)

    Kaushalendra Kumar JHA

    2015-12-01

    Full Text Available The Apatani, non-nomadic tribe, have evolved an ecologically sustainable system of rural forestry in Ziro Valley, a proposed heritage site of UNESCO. They have been using non-timber forest products (NTFPs grown in homestead and nearby forests for a very long period. The present study was aimed at identification of priority NTFPs and uses, their availability status and availability trend, conservation need, and sustainability interventions. Qualitative methods of research like, exploratory survey, questionnaire survey, focus group discussion, semi-structured interview of key informants, etc. were employed for data collection. The Apatani used 112 priority NTFPs for food supplement, herbal medicine, house building material and other purposes. However, on the basis of ecological importance such NTFPs were categorized as very low, low, moderate, high, and very high vulnerable species. Twenty vulnerable species like Antiitari ayi (Actinidia callosa, Biiling (Choerospondias axillaris, Henchi (Rubus niveus, Jojuru ayi (Coccinia grandis, Ngiilyang Khiiko (Centella asiatica etc. should be conserved and seventeen not vulnerable species at this stage like, Padii hamang (Cardamine hirsute, Sankhe (Quercus griffithii, Bije (Phyllostachys manii, Hiigu hamang (Oenanthe javanica, Kiira (Quercus dealbata , etc. could be commercialized. However, a balance needed to be struck between commercialization and conservation by adopting a comprehensive policy based on scientific and traditional Apatani knowledge for harvesting and regeneration of NTFPs. Homegardening or community farming is recommended for sustainable supply of commercially important species to be domasticated.

  8. Predicting biomass of hyperdiverse and structurally complex central Amazonian forests - a virtual approach using extensive field data

    Science.gov (United States)

    Magnabosco Marra, Daniel; Higuchi, Niro; Trumbore, Susan E.; Ribeiro, Gabriel H. P. M.; dos Santos, Joaquim; Carneiro, Vilany M. C.; Lima, Adriano J. N.; Chambers, Jeffrey Q.; Negrón-Juárez, Robinson I.; Holzwarth, Frederic; Reu, Björn; Wirth, Christian

    2016-03-01

    Old-growth forests are subject to substantial changes in structure and species composition due to the intensification of human activities, gradual climate change and extreme weather events. Trees store ca. 90 % of the total aboveground biomass (AGB) in tropical forests and precise tree biomass estimation models are crucial for management and conservation. In the central Amazon, predicting AGB at large spatial scales is a challenging task due to the heterogeneity of successional stages, high tree species diversity and inherent variations in tree allometry and architecture. We parameterized generic AGB estimation models applicable across species and a wide range of structural and compositional variation related to species sorting into height layers as well as frequent natural disturbances. We used 727 trees (diameter at breast height ≥ 5 cm) from 101 genera and at least 135 species harvested in a contiguous forest near Manaus, Brazil. Sampling from this data set we assembled six scenarios designed to span existing gradients in floristic composition and size distribution in order to select models that best predict AGB at the landscape level across successional gradients. We found that good individual tree model fits do not necessarily translate into reliable predictions of AGB at the landscape level. When predicting AGB (dry mass) over scenarios using our different models and an available pantropical model, we observed systematic biases ranging from -31 % (pantropical) to +39 %, with root-mean-square error (RMSE) values of up to 130 Mg ha-1 (pantropical). Our first and second best models had both low mean biases (0.8 and 3.9 %, respectively) and RMSE (9.4 and 18.6 Mg ha-1) when applied over scenarios. Predicting biomass correctly at the landscape level in hyperdiverse and structurally complex tropical forests, especially allowing good performance at the margins of data availability for model construction/calibration, requires the inclusion of predictors that express

  9. Predicting biomass of hyperdiverse and structurally complex Central Amazon forests - a virtual approach using extensive field data

    Science.gov (United States)

    Magnabosco Marra, D.; Higuchi, N.; Trumbore, S. E.; Ribeiro, G. H. P. M.; dos Santos, J.; Carneiro, V. M. C.; Lima, A. J. N.; Chambers, J. Q.; Negrón-Juárez, R. I.; Holzwarth, F.; Reu, B.; Wirth, C.

    2015-09-01

    Old-growth forests are subject to substantial changes in structure and species composition due to the intensification of human activities, gradual climate change and extreme weather events. Trees store ca. 90 % of the total AGB above-ground biomass in tropical forests and AGB estimation models are crucial for forest management and conservation. In the Central Amazon, predicting AGB at large spatial-scales is a challenging task due to the heterogeneity of successional stages, high tree species diversity and inherent variations in allometry and architecture. We parameterized generic AGB estimation models applicable across species and a wide range of structural and compositional variation related to species sorting into height layers as well as frequent natural disturbances. We used 727 trees from 101 genera and at least 135 species harvested in a contiguous forest near Manaus, Brazil. Sampling from this dataset we assembled six scenarios designed to span existing gradients in floristic composition and size distribution in order to select models that best predict AGB at the landscape-level across successional gradients. We found that good individual tree model fits do not necessarily translate into good predictions of AGB at the landscape level. When predicting AGB (dry mass) over scenarios using our different models and an available pantropical model, we observed systematic biases ranging from -31 % (pantropical) to +39 %, with RMSE root-mean-square error values of up to 130 Mg ha-1 (pantropical). Our first and second best models had both low mean biases (0.8 and 3.9 %, respectively) and RMSE (9.4 and 18.6 Mg ha-1) when applied over scenarios. Predicting biomass correctly at the landscape-level in complex tropical forests, especially allowing good performance at the margins of data availability for model parametrization, requires the inclusion of predictors related to species architecture. The model of interest should comprise the floristic composition and size

  10. Prediction of TF target sites based on atomistic models of protein-DNA complexes

    Directory of Open Access Journals (Sweden)

    Collado-Vides Julio

    2008-10-01

    Full Text Available Abstract Background The specific recognition of genomic cis-regulatory elements by transcription factors (TFs plays an essential role in the regulation of coordinated gene expression. Studying the mechanisms determining binding specificity in protein-DNA interactions is thus an important goal. Most current approaches for modeling TF specific recognition rely on the knowledge of large sets of cognate target sites and consider only the information contained in their primary sequence. Results Here we describe a structure-based methodology for predicting sequence motifs starting from the coordinates of a TF-DNA complex. Our algorithm combines information regarding the direct and indirect readout of DNA into an atomistic statistical model, which is used to estimate the interaction potential. We first measure the ability of our method to correctly estimate the binding specificities of eight prokaryotic and eukaryotic TFs that belong to different structural superfamilies. Secondly, the method is applied to two homology models, finding that sampling of interface side-chain rotamers remarkably improves the results. Thirdly, the algorithm is compared with a reference structural method based on contact counts, obtaining comparable predictions for the experimental complexes and more accurate sequence motifs for the homology models. Conclusion Our results demonstrate that atomic-detail structural information can be feasibly used to predict TF binding sites. The computational method presented here is universal and might be applied to other systems involving protein-DNA recognition.

  11. A cross-site comparison of factors influencing soil nitrification rates in northeastern USA forested watersheds

    Science.gov (United States)

    Ross, D.S.; Wemple, B.C.; Jamison, A.E.; Fredriksen, G.; Shanley, J.B.; Lawrence, G.B.; Bailey, S.W.; Campbell, J.L.

    2009-01-01

    Elevated N deposition is continuing on many forested landscapes around the world and our understanding of ecosystem response is incomplete. Soil processes, especially nitrification, are critical. Many studies of soil N transformations have focused on identifying relationships within a single watershed but these results are often not transferable. We studied 10 small forested research watersheds in the northeastern USA to determine if there were common factors related to soil ammonification and nitrification. Vegetation varied between mixed northern hardwoods and mixed conifers. Watershed surface soils (Oa or A horizons) were sampled at grid or transect points and analyzed for a suite of chemical characteristics. At each sampling point, vegetation and topographic metrics (field and GIS-based) were also obtained. Results were examined by watershed averages (n = 10), seasonal/watershed averages (n = 28), and individual sampling points (n = 608). Using both linear and tree regression techniques, the proportion of conifer species was the single best predictor of nitrification rates, with lower rates at higher conifer dominance. Similar to other studies, the soil C/N ratio was also a good predictor and was well correlated with conifer dominance. Unlike other studies, the presence of Acer saccharum was not by itself a strong predictor, but was when combined with the presence of Betula alleghaniensis. Topographic metrics (slope, aspect, relative elevation, and the topographic index) were not related to N transformation rates across the watersheds. Although found to be significant in other studies, neither soil pH, Ca nor Al was related to nitrification. Results showed a strong relationship between dominant vegetation, soil C, and soil C/N. ?? 2008 Springer Science+Business Media, LLC.

  12. Seasonal variations of dissolved organic carbon in precipitation over urban and forest sites in central Poland.

    Science.gov (United States)

    Siudek, Patrycja; Frankowski, Marcin; Siepak, Jerzy

    2015-07-01

    Spatial and temporal variability of carbon species in rainwater (bulk deposition) was studied for the first time at two sites located in urban area of Poznań City and protected woodland area (Jeziory), in central Poland, between April and December 2013. The mean concentration of total carbon (TC) for the first site was 5.86 mg L(-1), whereas for the second, 5.21 mg L(-1). Dissolved organic carbon (DOC) concentration accounted for, on average, 87 and 91 % of total carbon in precipitation at urban and non-urban sites, respectively. Significant changes in TC concentrations in rainwater were observed at both sites, indicating that atmospheric transformation, transport, and removal mechanisms of carbonaceous particles were affected by seasonal fluctuations in biogenic/anthropogenic emission and meteorological conditions (i.e., precipitation height and type, atmospheric transport). During the warm season, the DOC concentration in rainwater was mostly influenced by mixed natural and anthropogenic sources. In contrast, during the cold season, the DOC concentration significantly increased mainly as a result of anthropogenic activities, i.e., intensive coal combustion, domestic wood burning, high-temperature processes, etc. In addition, during the winter measurements, significant differences in mean DOC concentration (Kruskal-Wallis test, p urban and non-urban sites. These data imply that carbonaceous compounds are of crucial importance in atmospheric chemistry and should be considered as an important parameter while considering wet deposition, reactions with different substances, especially over polluted environments.

  13. Amazon rainforest exchange of carbon and subcanopy air flow: Manaus LBA site--a complex terrain condition.

    Science.gov (United States)

    Tóta, Julio; Fitzjarrald, David Roy; da Silva Dias, Maria A F

    2012-01-01

    On the moderately complex terrain covered by dense tropical Amazon Rainforest (Reserva Biologica do Cuieiras--ZF2--02°36'17.1'' S, 60°12'24.4'' W), subcanopy horizontal and vertical gradients of the air temperature, CO(2) concentration and wind field were measured for the dry and wet periods in 2006. We tested the hypothesis that horizontal drainage flow over this study area is significant and can affect the interpretation of the high carbon uptake rates reported by previous works at this site. A similar experimental design as the one by Tóta et al. (2008) was used with a network of wind, air temperature, and CO(2) sensors above and below the forest canopy. A persistent and systematic subcanopy nighttime upslope (positive buoyancy) and daytime downslope (negative buoyancy) flow pattern on a moderately inclined slope (12%) was observed. The microcirculations observed above the canopy (38 m) over the sloping area during nighttime presents a downward motion indicating vertical convergence and correspondent horizontal divergence toward the valley area. During the daytime an inverse pattern was observed. The micro-circulations above the canopy were driven mainly by buoyancy balancing the pressure gradient forces. In the subcanopy space the microcirculations were also driven by the same physical mechanisms but probably with the stress forcing contribution. The results also indicated that the horizontal and vertical scalar gradients (e.g., CO(2)) were modulated by these micro-circulations above and below the canopy, suggesting that estimates of advection using previous experimental approaches are not appropriate due to the tridimensional nature of the vertical and horizontal transport locally. This work also indicates that carbon budget from tower-based measurement is not enough to close the system, and one needs to include horizontal and vertical advection transport of CO(2) into those estimates.

  14. Charge Transfer at the Qo-Site of the Cytochrome bc1 Complex Leads to Superoxide Production

    DEFF Research Database (Denmark)

    Bøgh Salo, Adrian; Husen, Peter; Solov'yov, Ilia A

    2017-01-01

    interactions involving an occasionally trapped oxygen molecule (O2) at the so-called Qo site of the bc1 complex, which is one of the central active sites of the protein complex, where redox reactions are expected to occur. The investigation focuses on revealing the possibility of the oxygen molecule......The cytochrome bc1 complex is the third protein complex in the electron transport chain of mitochondria or photosynthetic bacteria, and it serves to create an electrochemical gradient across a cellular membrane, which is used to drive ATP synthesis. The purpose of this study is to investigate...

  15. Response of Competing Vegetation to Site Preparation on West Gulf Coastal Plain Commercial Forest Land

    Science.gov (United States)

    Gale L. Wolters; Henry A. Pearson; Ronald E. Thill; V. Clark Baldwin; Alton Martin

    1995-01-01

    The response of woody and herbaceous vegetation to site preparation, subsoil texture, and fertilization was measured on the West Gulf Coastal Plain. The influences of these treatments on competing vegetation were short-term. Drastic soil disturbance and fertilization briefly increased herbage production. Shear-windrow and shear-disk were generally the most effective...

  16. Long-Term Monitoring Network Optimization Evaluation for Operable Unit 2, Bunker Hill Mining and Metallurgical Complex Superfund Site, Idaho

    Science.gov (United States)

    This report presents a description and evaluation of the ground water and surface water monitoring program associated with the Bunker Hill Mining and Metallurgical Complex Superfund Site (Bunker Hill) Operable Unit (OU) 2.

  17. Mapping vegetation and fuels for fire management on the Gila National Forest Complex, New Mexico

    Science.gov (United States)

    Robert E. Keane; Scott A. Mincemoyer; Kirsten M. Schmidt; Donald G. Long; Janice L. Garner

    2000-01-01

    (Please note: This PDF is part of a CD-ROM package only and was not printed on paper.) Fuels and vegetation spatial data layers required by the spatially explicit fire growth model FARSITE were developed for all lands in and around the Gila National Forest in New Mexico. Satellite imagery, terrain modeling, and biophysical simulation were used to create the three...

  18. Distribution and Characterization of Armillaria Complex in Atlantic Forest Ecosystems of Spain

    Directory of Open Access Journals (Sweden)

    Nebai Mesanza

    2017-06-01

    Full Text Available Armillaria root disease is a significant forest health concern in the Atlantic forest ecosystems in Spain. The damage occurs in conifers and hardwoods, causing especially high mortality in young trees in both native forests and plantations. In the present study, the distribution of Armillaria root disease in the forests and plantations of the Basque Country is reported. Armillaria spp. were more frequently isolated from stands with slopes of 20–30% and west orientation, acid soils with high permeability, deciduous hosts, and a rainfall average above 1800 mm. In a large-scale survey, 35% of the stands presented Armillaria structures and showed disease symptoms. Of the isolated Armillaria samples, 60% were identified using molecular methods as A. ostoyae, 24% as A. mellea, 14% as A. gallica, 1% as A. tabescens, and 1% as A. cepistipes. In a small scale sampling, population diversity was defined by somatic compatibility tests and Universally Primed-PCR technique. Finally, the pathogenicity of A. mellea, the species with the broadest host range, was determined on different tree species present in the Atlantic area of Spain in order to determine their resistance levels to Armillaria disease. A significant difference in disease severity was observed among tree species (p < 0.001, with Pinus radiata being the most susceptible tree species and Cryptomeria japonica the most resistant to A. mellea.

  19. Learning to manage a complex ecosystem: adaptive management and the Northwest Forest Plan.

    Science.gov (United States)

    George H. Stankey; Roger N. Clark; Bernard T. Bormann

    2006-01-01

    The Northwest Forest Plan (the Plan) identifies adaptive management as a central strategy for effective implementation. Despite this, there has been a lack of any systematic evaluation of its performance. This study is based on an extensive literature review, 50 interviews with resource managers and scientists involved with the Plan’s implementation, and a survey of...

  20. Deciduous forest responses to temperature, precipitation, and drought imply complex climate change impacts.

    Science.gov (United States)

    Xie, Yingying; Wang, Xiaojing; Silander, John A

    2015-11-03

    Changes in spring and autumn phenology of temperate plants in recent decades have become iconic bio-indicators of rapid climate change. These changes have substantial ecological and economic impacts. However, autumn phenology remains surprisingly little studied. Although the effects of unfavorable environmental conditions (e.g., frost, heat, wetness, and drought) on autumn phenology have been observed for over 60 y, how these factors interact to influence autumn phenological events remain poorly understood. Using remotely sensed phenology data from 2001 to 2012, this study identified and quantified significant effects of a suite of environmental factors on the timing of fall dormancy of deciduous forest communities in New England, United States. Cold, frost, and wet conditions, and high heat-stress tended to induce earlier dormancy of deciduous forests, whereas moderate heat- and drought-stress delayed dormancy. Deciduous forests in two eco-regions showed contrasting, nonlinear responses to variation in these explanatory factors. Based on future climate projection over two periods (2041-2050 and 2090-2099), later dormancy dates were predicted in northern areas. However, in coastal areas earlier dormancy dates were predicted. Our models suggest that besides warming in climate change, changes in frost and moisture conditions as well as extreme weather events (e.g., drought- and heat-stress, and flooding), should also be considered in future predictions of autumn phenology in temperate deciduous forests. This study improves our understanding of how multiple environmental variables interact to affect autumn phenology in temperate deciduous forest ecosystems, and points the way to building more mechanistic and predictive models.

  1. Charge Transfer at the Qo-Site of the Cytochrome bc1 Complex Leads to Superoxide Production.

    Science.gov (United States)

    Salo, Adrian Bøgh; Husen, Peter; Solov'yov, Ilia A

    2017-03-02

    The cytochrome bc1 complex is the third protein complex in the electron transport chain of mitochondria or photosynthetic bacteria, and it serves to create an electrochemical gradient across a cellular membrane, which is used to drive ATP synthesis. The purpose of this study is to investigate interactions involving an occasionally trapped oxygen molecule (O2) at the so-called Qo site of the bc1 complex, which is one of the central active sites of the protein complex, where redox reactions are expected to occur. The investigation focuses on revealing the possibility of the oxygen molecule to influence the normal operation of the bc1 complex and acquire an extra electron, thus becoming superoxide, a biologically toxic free radical. The process is modeled by applying quantum chemical calculations to previously performed classical molecular dynamics simulations. Investigations reveal several spontaneous charge transfer modes from amino acid residues and cofactors at the Qo-site to the trapped O2 molecule.

  2. Top-down, Bottom-up and Sideways: The Multilayered Complexities of Multi-level Actors Shaping Forest Governance and REDD+ Arrangements in Madre de Dios, Peru.

    Science.gov (United States)

    Rodriguez-Ward, Dawn; Larson, Anne M; Ruesta, Harold Gordillo

    2018-01-03

    This study examines the role multilevel governance plays in the adoption of sustainable landscape management initiatives in emerging arrangements aimed at reducing emissions from deforestation and forest degradation (REDD+). It sheds light on the challenges these multiple layers of actors and interests encounter around such alternatives in a subnational jurisdiction. Through transcript analysis of 93 interviews with institutional actors in the region of Madre de Dios, Peru, particularly with regard to five sites of land-use change, we identified the multiple actors who are included and excluded in the decision-making process and uncovered their complex interactions in forest and landscape governance and REDD+ arrangements. Madre de Dios is a useful case for studying complex land-use dynamics, as it is home to multiple natural resources, a large mix of actors and interests, and a regional government that has recently experienced the reverberations of decentralization. Findings indicate that multiple actors shaped REDD+ to some extent, but REDD+ and its advocates were unable to shape land-use dynamics or landscape governance, at least in the short term. In the absence of strong and effective regional regulation for sustainable land use alternatives and the high value of gold on the international market, illegal gold mining proved to be a more profitable land-use choice. Although REDD+ created a new space for multilevel actor interaction and communication and new alliances to emerge, the study questions the prevailing REDD+ discourse suggesting that better coordination and cooperation will lead to integrated landscape solutions. For REDD+ to be able to play a role in integrated landscape governance, greater attention needs to be paid to grassroots actors, power and authority over territory and underlying interests and incentives for land-use change.

  3. Observed and Modeled Isoprene Fluxes at a Remote Michigan Forest Site

    Science.gov (United States)

    Wen, M.; Pressley, S. N.; Gu, D.; Yu, H.; Guenther, A. B.; VanReken, T. M.

    2015-12-01

    Biogenic volatile organic compounds (BVOCs) constitute a major part of global VOC emissions and can affect regional or global climate by influencing tropospheric chemistry and forming secondary organic aerosols. Isoprene is the most abundant species in global BVOC budget. The Model of Emissions of Gases and Aerosols from Nature (MEGAN) 2.1 (Guenther et al., 2006, 2012) is a state-of-art emission model that simulates BVOC emissions by considering major environmental activity factors (e.g. temperature, solar radiation). Here we compare measurements of isoprene emissions in a mixed hardwood forest at the University of Michigan Biological Station (UMBS) during 1999-2005 growing seasons (Pressley et al., 2004, 2005) with MEGAN model simulations. We investigated the seasonal variations of isoprene emissions by considering the impacts from meteorological conditions, as well as correlations between sensible heat flux, latent heat flux and isoprene flux for a model uncertainty analysis. Model simulations are in good agreement with observations during leaf full expansion periods, but the values are 3-4 times higher than observations before full leaf development and after leaf senescence periods. There are significant correlations between the variations of isoprene emissions and precipitation.

  4. "I know, therefore I adapt?" Complexities of individual adaptation to climate-induced forest dieback in Alaska

    Directory of Open Access Journals (Sweden)

    Lauren E. Oakes

    2016-06-01

    Full Text Available Individual actions to avoid, benefit from, or cope with climate change impacts partly shape adaptation; much research on adaptation has focused at the systems level, overlooking drivers of individual responses. Theoretical frameworks and empirical studies of environmental behavior identify a complex web of cognitive, affective, and evaluative factors that motivate stewardship. We explore the relationship between knowledge of, and adaptation to, widespread, climate-induced tree mortality to understand the cognitive (i.e., knowledge and learning, affective (i.e., attitudes and place attachment, and evaluative (i.e., use values factors that influence how individuals respond to climate-change impacts. From 43 semistructured interviews with forest managers and users in a temperate forest, we identified distinct responses to local, climate-induced environmental changes that we then categorized as either behavioral or psychological adaptations. Interviewees developed a depth of knowledge about the dieback through a combination of direct, place-based experiences and indirect, mediated learning through social interactions. Knowing that the dieback was associated with climate change led to different adaptive responses among the interviewees, although knowledge alone did not explain this variation. Forest users reported psychological adaptations to process negative attitudes; these adaptations were spurred by knowledge of the causes, losses of intangible values, and impacts to a species to which they held attachment. Behavioral adaptations exclusive to a high level of knowledge included actions such as using the forests to educate others or changing transportation behaviors to reduce personal energy consumption. Managers integrated awareness of the dieback and its dynamics across spatial scales into current management objectives. Our findings suggest that adaptive management may occur from the bottom up, as individual managers implement new practices in

  5. United States Department of Agriculture Forest Service 1996 annual report wetlands research related to the Pen Branch restoration effort on the Savannah River site

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, E.A. [Westinghouse Savannah River Company, Aiken, SC (United States); Kolka, R.K. [USDA Forest Service, Charleston, SC (United States); Trettin, C.C. [USDA Forest Service, Charleston, SC (United States)

    1997-01-01

    This report documents the role of the USDA Forest Service and their collaborators (SRTC, SREL, and several universities) in wetlands monitoring and research on the Savannah River Site. This report describes the rationales, methods, and results (when available) of these studies and summarizes and integrates the available information through 1996.

  6. Variation in transfer factor of radiocaesium in bank voles (Clethrionomys glareolus) in clear cut and mature forest sites after the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Palo, Thomas R. [Mid-Sweden University, Department of Natural Sciences, Holmgatan 10, 85170 Sundsvall (Sweden)]. E-mail: thomas.palo@miun.se

    2007-07-01

    Bank voles that were collected between 1986 and 2004 at sites in Chernobyl fallout areas of northern Sweden showed higher {sup 137}Cs activity concentrations at the mature forest sites compared to clear cuts. This difference was not attributed to differences in ground deposition between sites but to differences in aggregated transfer rates to voles. Differences in transfer between forest types were evident for all years 1986-2004 but the change occurred at different rates in the two habitats. The apparent transfer factor between bilberry (Vaccinium myrtillus) and voles was positively related and indicated that a biomagnification was about 1.5 from vegetation to these small mammalian herbivores. The aggregated transfer factor to bank voles measured in the forest habitat, although starting at higher levels declined faster with time than clear cut sites and the differences between the forest habitat and the clear cut areas diminished with time. After the Chernobyl accident in 1986 the mean level in bank vole was 514 Bq/kg fresh mass (SD = 505) that increased to 1485 Bq/kg (SD = 881) in 1988. The activity concentration declined thereafter. The bank voles collected in similar habitats in 2004 contained on average 1022 Bq/kg (SD = 723). Still 18 years after the radionuclide fallout over Sweden high activity concentrations in voles could be found.

  7. Missouri Ozark Forest Ecosystem Project: site history, soils, landforms, woody and herbaceous vegetation, down wood, and inventory methods for the landscape experiment.

    Science.gov (United States)

    Stephen R. Shifley; Brian L., eds. Brookshire

    2000-01-01

    Describes vegetation and physical site conditions at the initiation (1991-1995) of the Missouri Ozark Forest Ecosystem Project (MOFEP) in the southeastern Missouri Ozarks. Provides detailed information on sampling protocols and summarizes initial conditions of the landscape experiment prior to harvest treatments. Summaries are by plot, by ~800-acre...

  8. LBA-ECO CD-10 Coarse Woody Debris Data at km 67 Tower Site, Tapajos National Forest

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data sets reports properties of fallen course woody debris in an old-growth upland forest at the Para Western (Santarem) - km 67, Primary Forest Tower...

  9. LBA-ECO CD-10 Tree DBH Measurements at the km 67 Tower Site, Tapajos National Forest

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data sets reports diameter at breast height (DBH) measurements in the old-growth upland forest at the Para Western (Santarem) - km 67, Primary Forest...

  10. LBA-ECO CD-10 Ground-based Biometry Data at km 67 Tower Site, Tapajos National Forest

    Data.gov (United States)

    National Aeronautics and Space Administration — This data sets contains a single text file which reports biometry measurements of the old-growth upland forest at the Para, Western (Santarem)km 67, Primary Forest...

  11. LBA-ECO CD-10 Tree DBH Measurements at the km 67 Tower Site, Tapajos National Forest

    Data.gov (United States)

    National Aeronautics and Space Administration — This data sets reports diameter at breast height (DBH) measurements in the old-growth upland forest at the Para Western (Santarem) - km 67, Primary Forest Tower...

  12. Bimetallic Complexes Supported by a Redox-Active Ligand with Fused Pincer-Type Coordination Sites.

    Science.gov (United States)

    Wang, Denan; Lindeman, Sergey V; Fiedler, Adam T

    2015-09-08

    The remarkable chemistry of mononuclear complexes featuring tridentate, meridionally chelating "pincer" ligands has stimulated the development of ligand frameworks containing multiple pincer sites. Here, the coordination chemistry of a novel pentadentate ligand (L(N3O2)) that provides two closely spaced NNO pincer-type compartments fused together at a central diarylamido unit is described. The trianionic L(N3O2) chelate supports homobimetallic structures in which each M(II) ion (M = Co, Cu, Zn) is bound in a meridional fashion by the bridging diarylamido N atom and O,N-donors of the salicyaldimine arms. The metal centers are also coordinated by a mono- or bidentate auxiliary ligand (L(aux)), resulting in complexes with the general form [M2(L(N3O2))(L(aux))2](+) (where L(aux) = 1-methyl-benzimidazole (1MeBI), 2,2'-bipyridine (bpy), 4,4'-dibromo-2,2'-bipyridine (bpy(Br2)), or (S)-2-(4-isopropyl-4,5-dihydrooxazolyl)pyridine (S-(iPr)OxPy)). The fused nature of the NNO pincer sites results in short metal-metal distances ranging from 2.70 Å for [Co2(L(N3O2)) (bpy)2](+) to 3.28 Å for [Zn2(L(N3O2)) (bpy)2](+), as revealed by X-ray crystallography. The complexes possess C2 symmetry due to the twisting of the aryl rings of the μ-NAr2 core; spectroscopic studies indicate that chiral L(aux) ligands, such as S-(iPr)OxPy, are capable of controlling the helical sense of the L(N3O2) scaffold. Since the four- or five-coordinate M(II) centers are linked solely by the amido moiety, each features an open coordination site in the intermetallic region, allowing for the possibility of metal-metal cooperativity in small-molecule activation. Indeed, the dicobalt(II) complex [Co2(L(N3O2)) (bpy(Br2))2](+) reacts with O2 to yield a dicobalt(III) species with a μ-1,2-peroxo ligand. The bpy-containing complexes exhibit rich electrochemical properties due to multiple metal- and ligand-based redox events across a wide (3.0 V) potential window. Using electron paramagnetic resonance (EPR

  13. Salivary film expresses a complex, macromolecular binding site for Streptococcus sanguis.

    Science.gov (United States)

    Gong, K; Mailloux, L; Herzberg, M C

    2000-03-24

    Teeth in the oral cavity are coated with a salivary film or pellicle, which lacks apparent intermolecular organization. This heterogeneous film facilitates binding of early commensal colonizing bacteria, including Streptococcus sanguis. To test the hypothesis that sufficient intermolecular organization exists in salivary films to form binding sites for S. sanguis, an in vitro model of saliva-coated teeth was probed with murine anti-idiotypical monoclonal antibodies (mAb2, anti-ids). The anti-ids were harvested from hybridomas that were developed in response to first generation murine hybridomas that produced anti-S. sanguis adhesin monoclonal antibodies (mAb1). The anti-ids (i) reacted with experimental salivary films and inhibited S. sanguis adhesion in a dose-dependent fashion. In Western blots, the anti-ids (ii) recognized a high molecular weight salivary antigen and (iii) secretory IgA (sIgA) light chain and alpha-amylase. After isolation by gel filtration from whole saliva or mixed secretory IgA and alpha-amylase, the high molecular weight component, containing amylase activity and sIgA, bound to hydroxyapatite to promote adhesion of S. sanguis. Therefore, a complex enriched in secretory immunoglobulin A and alpha-amylase forms a S. sanguis-binding site.

  14. Spontaneous Binding of Molecular Oxygen at the Qo-Site of the bc1 Complex Could Stimulate Superoxide Formation

    DEFF Research Database (Denmark)

    Husen, Peter; Solov'yov, Ilia A

    2016-01-01

    to drive ATP synthesis. This molecular machinery, however, is suspected to be a source of superoxide, which is toxic to the cell, even in minuscular quantities, and believed to be a factor in aging. Through molecular dynamics simulations, we investigate here the migration of molecular oxygen in the bc1...... complex in order to identify possible reaction sites that could lead to superoxide formation. It is found, in particular, that oxygen penetrates spontaneously the Qo binding site of the bc1 complex in the presence of an intermediate semiquinone radical, thus making the Qo-site a strong candidate for being...... a center of superoxide production....

  15. The link between atmospheric radicals and newly formed particles at a spruce forest site in Germany

    DEFF Research Database (Denmark)

    Bonn, B.; Bourtsoukidis, E.; Sun, T. S.

    2013-01-01

    measurements during the rest of the diurnal cycle. Including large organic radicals, i.e. organic peroxy radicals (RO2) deriving from monoterpenes and their oxidation products in the nucleation mechanism improved the correlation between observed and simulated J3. This supports a recently proposed empirical...... relationship for new particle formation that has been used in global models. However, the best match between theory and measurements for the site of interest was found for an activation process based on large organic peroxy radicals and stabilized Criegee intermediates (sCI). This novel laboratory derived...

  16. The link between atmospheric radicals and newly formed particles at a spruce forest site in Germany

    DEFF Research Database (Denmark)

    Bonn, B.; Bourtsoukidis, E.; Sun, T. S.

    2014-01-01

    during the rest of the diurnal cycle. Including large organic radicals, i.e. organic peroxy radicals (RO2) deriving from monoterpenes and their oxidation products, in the nucleation mechanism improved the correlation between observed and simulated J3. This supports a recently proposed empirical...... relationship for new particle formation that has been used in global models. However, the best match between theory and measurements for the site of interest was found for an activation process based on large organic peroxy radicals and stabilised Criegee intermediates (sCI). This novel laboratory...

  17. The interactions between soil-biosphere-atmosphere (ISBA) land surface model multi-energy balance (MEB) option in SURFEXv8 - Part 2: Introduction of a litter formulation and model evaluation for local-scale forest sites

    Science.gov (United States)

    Napoly, Adrien; Boone, Aaron; Samuelsson, Patrick; Gollvik, Stefan; Martin, Eric; Seferian, Roland; Carrer, Dominique; Decharme, Bertrand; Jarlan, Lionel

    2017-04-01

    Land surface models (LSMs) need to balance a complicated trade-off between computational cost and complexity in order to adequately represent the exchanges of energy, water and matter with the atmosphere and the ocean. Some current generation LSMs use a simplified or composite canopy approach that generates recurrent errors in simulated soil temperature and turbulent fluxes. In response to these issues, a new version of the interactions between soil-biosphere-atmosphere (ISBA) land surface model has recently been developed that explicitly solves the transfer of energy and water from the upper canopy and the forest floor, which is characterized as a litter layer. The multi-energy balance (MEB) version of ISBA is first evaluated for three well-instrumented contrasting local-scale sites, and sensitivity tests are performed to explore the behavior of new model parameters. Second, ISBA-MEB is benchmarked against observations from 42 forested sites from the global micro-meteorological network (FLUXNET) for multiple annual cycles.It is shown that ISBA-MEB outperforms the composite version of ISBA in improving the representation of soil temperature, ground, sensible and, to a lesser extent, latent heat fluxes. Both versions of ISBA give comparable results in terms of simulated latent heat flux because of the similar formulations of the water uptake and the stomatal resistance. However, MEB produces a better agreement with the observations of sensible heat flux than the previous version of ISBA for 87.5 % of the simulated years across the 42 forested FLUXNET sites. Most of this improvement arises owing to the improved simulation of the ground conduction flux, which is greatly improved using MEB, especially owing to the forest litter parameterization. It is also shown that certain processes are also modeled more realistically (such as the partitioning of evapotranspiration into transpiration and ground evaporation), even if certain statistical performances are neutral. The

  18. Temporal change in soil carbon stability at a paired old-growth douglas-fir forest/clear-cut site

    Science.gov (United States)

    Forest ecosystems are estimated to contain one-half of the total terrestrial carbon (C) pool (1146 Pg), with two-thirds of this C (787 Pg) residing in forest soils. Given the magnitude of this C pool, it is critical to understand the effects of forest management practices on soil...

  19. Connecting non-timber forest products stakeholders to information and knowledge: A case study of an Internet web site

    Science.gov (United States)

    James Chamberlain; Matt Winn; A.L. Hammett

    2009-01-01

    Many products are harvested from forests that are not timber-based but are based on plant materials. These non-timber forest products (NTFPs) have not been fully incorporated into economic development programs, yet they provide significant monetary benefits for rural entrepreneurs. Interest in NTFPs as alternative forest enterprises and sources of additional income has...

  20. LBA-ECO TG-07 Ground-based Biometry Data at km 83 Site, TapajosNational Forest: 1997

    Science.gov (United States)

    M.M. Keller; M.W. Palace

    2009-01-01

    A field inventory of trees was conducted in March of 1997 in a logging concession at the Tapajos National Forest, south of Santarem, Para, Brazil. The inventory was conducted by the foresters and technicians of the Tropical Forest Foundation (FFT) and included all trees with diameter at breast height greater than or equal to 35 cm. Four blocks of approximately 100 ha...

  1. The value of roaded, multiple-use areas as recreation sites in three national forests of the Pacific Northwest.

    Science.gov (United States)

    Roger N. Clark; Russell W. Koch; Mack L. Hogans; Harriet H. Christensen; John C. Hendee

    1984-01-01

    Dispersed recreation along forest roads in generally undeveloped areas is increasing rapidly in the West. To effectively manage this use and integrate it with other forest activities requires information about the preferences, expectations, and opinions of forest visitors and their patterns of recreation use. Results of a 3-year study of campers and day users in three...

  2. Establishment and Data Collection of Vegetation-related Studies on the Missouri Ozark Forest Ecosystem Project Study Sites

    Science.gov (United States)

    Brian L. Brookshire; Daniel C. Dey

    2000-01-01

    The Missouri Ozark Forest Ecosystem Project (MOFEP) is an experiment designed to determine the effects of forest management practices on important ecosystem attributes. MOFEP treatments evaluated include even-aged, uneven-aged, and no management treatments. Forest vegetation provides a common ecological link among many organisms and ecological processes, and therefore...

  3. Proteomics Analysis with a Nano Random Forest Approach Reveals Novel Functional Interactions Regulated by SMC Complexes on Mitotic Chromosomes.

    Science.gov (United States)

    Ohta, Shinya; Montaño-Gutierrez, Luis F; de Lima Alves, Flavia; Ogawa, Hiromi; Toramoto, Iyo; Sato, Nobuko; Morrison, Ciaran G; Takeda, Shunichi; Hudson, Damien F; Rappsilber, Juri; Earnshaw, William C

    2016-08-01

    Packaging of DNA into condensed chromosomes during mitosis is essential for the faithful segregation of the genome into daughter nuclei. Although the structure and composition of mitotic chromosomes have been studied for over 30 years, these aspects are yet to be fully elucidated. Here, we used stable isotope labeling with amino acids in cell culture to compare the proteomes of mitotic chromosomes isolated from cell lines harboring conditional knockouts of members of the condensin (SMC2, CAP-H, CAP-D3), cohesin (Scc1/Rad21), and SMC5/6 (SMC5) complexes. Our analysis revealed that these complexes associate with chromosomes independently of each other, with the SMC5/6 complex showing no significant dependence on any other chromosomal proteins during mitosis. To identify subtle relationships between chromosomal proteins, we employed a nano Random Forest (nanoRF) approach to detect protein complexes and the relationships between them. Our nanoRF results suggested that as few as 113 of 5058 detected chromosomal proteins are functionally linked to chromosome structure and segregation. Furthermore, nanoRF data revealed 23 proteins that were not previously suspected to have functional interactions with complexes playing important roles in mitosis. Subsequent small-interfering-RNA-based validation and localization tracking by green fluorescent protein-tagging highlighted novel candidates that might play significant roles in mitotic progression. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  4. fhlA repression by OxyS RNA: kissing complex formation at two sites results in a stable antisense-target RNA complex.

    Science.gov (United States)

    Argaman, L; Altuvia, S

    2000-07-28

    OxyS is a small untranslated RNA that is induced in response to oxidative stress in Escherichia coli. This small RNA acts as a global regulator affecting the expression of multiple genes. OxyS represses the translation of fhlA, a transcriptional activator for formate metabolism. Previously, we have shown that fhlA repression by OxyS is mediated through base-pairing with a short sequence overlapping the ribosome binding site. Here we show that the OxyS-fhlA interaction involves a second site residing further downstream, within the coding region of fhlA. Mutations that disrupt pairing at this site affect the ability of OxyS to prevent 30 S ribosomes from binding to fhlA mRNA. Structure probing of fhlA mRNA demonstrates that both sites reside in the loops of two stem-loop structures. OxyS-fhlA pairing analysis shows that OxyS binds wild-type fhlA with an apparent dissociation constant of 25 nM, indicating that kissing complex formation between OxyS and fhlA results in a stable antisense-target complex. Mutations at either site, which disrupt pairing of OxyS to fhlA, decrease the stability of this complex. Our results indicate that kissing complex formation is sufficient to repress fhlA translation by OxyS. Copyright 2000 Academic Press.

  5. Re-Inversion of Surface Electrical Resistivity Tomography Data from the Hanford Site B-Complex

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Timothy C.; Wellman, Dawn M.

    2013-05-01

    This report documents the three-dimensional (3D) inversion results of surface electrical resistivity tomography (ERT) data collected over the Hanford Site B-Complex. The data were collected in order to image the subsurface distribution of electrically conductive vadose zone contamination resulting from both planned releases of contamination into subsurface infiltration galleries (cribs, trenches, and tile fields), as well as unplanned releases from the B, BX, and BY tank farms and/or associated facilities. Electrically conductive contaminants are those which increase the ionic strength of pore fluids compared to native conditions, which comprise most types of solutes released into the subsurface B-Complex. The ERT data were collected and originally inverted as described in detail in report RPP-34690 Rev 0., 2007, which readers should refer to for a detailed description of data collection and waste disposal history. Although the ERT imaging results presented in that report successfully delineated the footprint of vadose zone contamination in areas outside of the tank farms, imaging resolution was not optimized due to the inability of available inversion codes to optimally process the massive ERT data set collected at the site. Recognizing these limitations and the potential for enhanced ERT characterization and time-lapse imaging at contaminated sites, a joint effort was initiated in 2007 by the U.S. Department of Energy – Office of Science (DOE-SC), with later support by the Office of Environmental Management (DOE-EM), and the U.S. Department of Defense (DOD), to develop a high-performance distributed memory parallel 3D ERT inversion code capable of optimally processing large ERT data sets. The culmination of this effort was the development of E4D (Johnson et al., 2010,2012) In 2012, under the Deep Vadose Zone Applied Field Research Initiative (DVZ-AFRI), the U.S. Department of Energy – Richland Operations Office (DOE-RL) and CH2M Hill Plateau Remediation

  6. Application of ecosystem model and Markov Chain Monte Carlo method for parameter optimization and ecosystem productivity prediction at seven forest flux sites across North America

    Science.gov (United States)

    Peng, C.; Zhou, X.

    2015-12-01

    To reduce simulation uncertainties due to inaccurate model parameters, the Markov Chain Monte Carlo (MCMC) method was applied in this study to improve the estimations of four key parameters used in the process-based ecosystem model of TRIPLEX-FLUX. These four key parameters include a maximum photosynthetic carboxylation rate of 25°C (Vcmax), an electron transport (Jmax) light-saturated rate within the photosynthetic carbon reduction cycle of leaves, a coefficient of stomatal conductance (m), and a reference respiration rate of 10ºC (R10). Seven forest flux tower sites located across North America were used to investigate and facilitate understanding of the daily variation in model parameters for three deciduous forests, three evergreen temperate forests, and one evergreen boreal forest. Eddy covariance CO2 exchange measurements were assimilated to optimize the parameters in the year 2006. After parameter optimization and adjustment took place, net ecosystem production prediction significantly improved (by approximately 25%) compared to the CO2 flux measurements taken at the seven forest ecosystem sites.

  7. Challenges in model-data fusion: Detecting and quantifying parameter equifinality and uncertainty in a recently clear-cut site in Harvard forest

    Science.gov (United States)

    Ghimire, B.; Williams, C. A.; Panday, P. K.

    2012-12-01

    Model-data fusion techniques have been increasingly used to forge new understanding on the carbon, water, and energy fluxes between the atmosphere and land. Such techniques integrate multiple data streams into a modeling framework and derive parameter estimates by maximizing the fit between model predictions and observations. These techniques are advantageous because they overcome some of the challenges in parameter estimation caused by mismatches of scale of data collected and analyzed, inability to transfer parameter values in space and time, and lack of direct field based observations. Most of the attention in past model-data fusion studies has been with deriving model parameters, and subsequently applying those parameters to model underlying fluxes. However the caveats of these techniques need to be addressed for deriving meaningful parameter estimates to understand the processes controlling these fluxes. One of the major problems in the modeling process relates to parameter equifinality (i.e., correlations) where non-unique parameter solutions exist that can explain the variability in observed data. Parameter equifinality is associated with different model parameter estimates producing sufficiently high fit between model predictions and observations. This study presents a new set of statistical measures to detect and quantify parameter equifinality in a model-data fusion scheme, and applies these measures to a SVAT (soil-vegetation-atmosphere transfer) model constrained by multiple data streams (e.g., eddy covariance and micrometerological observations) in a recently clear-cut forest site in Harvard forest, Massachusetts. The results of this study demonstrate that equifinality is a complex phenomenon, and varies with the size of the parameter space. The parameters influenced by equifinality can be segregated into discrete groups. For example, maximum Rubisco capacity, Ball-Berry slope, and leaf area index parameters belong to a highly correlated parameter

  8. Model-experiment synthesis at two FACE sites in the southeastern US. Forest ecosystem responses to elevated CO[2]. (Invited)

    Science.gov (United States)

    Walker, A. P.; Zaehle, S.; De Kauwe, M. G.; Medlyn, B. E.; Dietze, M.; Hickler, T.; Iversen, C. M.; Jain, A. K.; Luo, Y.; McCarthy, H. R.; Parton, W. J.; Prentice, C.; Thornton, P. E.; Wang, S.; Wang, Y.; Warlind, D.; Warren, J.; Weng, E.; Hanson, P. J.; Oren, R.; Norby, R. J.

    2013-12-01

    Ecosystem observations from two long-term Free-Air CO[2] Enrichment (FACE) experiments (Duke forest and Oak Ridge forest) were used to evaluate the assumptions of 11 terrestrial ecosystem models and the consequences of those assumptions for the responses of ecosystem water, carbon (C) and nitrogen (N) fluxes to elevated CO[2] (eCO[2]). Nitrogen dynamics were the main constraint on simulated productivity responses to eCO[2]. At Oak Ridge some models reproduced the declining response of C and N fluxes, while at Duke none of the models were able to maintain the observed sustained responses. C and N cycles are coupled through a number of complex interactions, which causes uncertainty in model simulations in multiple ways. Nonetheless, the major difference between models and experiments was a larger than observed increase in N-use efficiency and lower than observed response of N uptake. The results indicate that at Duke there were mechanisms by which trees accessed additional N in response to eCO[2] that were not represented in the ecosystem models, and which did not operate with the same efficiency at Oak Ridge. Sequestration of the additional productivity under eCO[2] into forest biomass depended largely on C allocation. Allocation assumptions were classified into three main categories--fixed partitioning coefficients, functional relationships and a partial (leaf allocation only) optimisation. The assumption which best constrained model results was a functional relationship between leaf area and sapwood area (pipe-model) and increased root allocation when nitrogen or water were limiting. Both, productivity and allocation responses to eCO[2] determined the ecosystem-level response of LAI, which together with the response of stomatal conductance (and hence water-use efficiency; WUE) determined the ecosystem response of transpiration. Differences in the WUE response across models were related to the representation of the relationship of stomatal conductance to CO[2] and

  9. Water and nitrate fluxes at a forest site in the North Tyrolean Limestone Alps.

    Science.gov (United States)

    Feichtinger, Franz; Smidt, Stefan; Klaghofer, Eduard

    2002-01-01

    The water balance for the site Mühleggerköpfl in the North Tyrolean Limestone Alps has been established to a soil depth of 50 cm. The evaporation amounts to 42% and deep percolation is 58% of the precipitation. The surface runoff was negligible and therefore the according nitrate fluxes as welL Soil water analysis revealed mean nitrate concentrations of 3 to 15 mg NO3 L(-1), depending on soil depth. The nitrate concentrations at 50 cm soil depth and the associated percolation rates led to NO3-N outputs of 15.9 kg NO3-N ha(-1) in the year 1999 and 7.9 kg NO3-N ha(-1) in the year 2000.

  10. Exemplifying whole-plant ozone uptake in adult forest trees of contrasting species and site conditions

    Energy Technology Data Exchange (ETDEWEB)

    Nunn, Angela J. [Ecophysiology of Plants, Department of Ecology, Technical University of Muenchen, Am Hochanger 13, D-85354 Freising, Bavaria (Germany)]. E-mail: nunn@wzw.tum.de; Wieser, Gerhard [Federal Research and Training Centre for Forests, Natural Hazards and Landscape, Unit Alpine Timberline Ecophysiology, Rennweg 1, 6020 Innsbruck (Austria); Metzger, Ursula [Ecophysiology of Plants, Department of Ecology, Technical University of Muenchen, Am Hochanger 13, D-85354 Freising, Bavaria (Germany); Loew, Markus [Ecophysiology of Plants, Department of Ecology, Technical University of Muenchen, Am Hochanger 13, D-85354 Freising, Bavaria (Germany); Wipfler, Philip [Forest Yield Science, Technical University of Muenchen, Am Hochanger 13, D-85354 Freising (Germany); Haeberle, Karl-Heinz [Ecophysiology of Plants, Department of Ecology, Technical University of Muenchen, Am Hochanger 13, D-85354 Freising, Bavaria (Germany); Matyssek, Rainer [Ecophysiology of Plants, Department of Ecology, Technical University of Muenchen, Am Hochanger 13, D-85354 Freising, Bavaria (Germany)

    2007-04-15

    Whole-tree O{sub 3} uptake was exemplified for Picea abies, Fagus sylvatica and Larix decidua in stands at high and low altitude and contrasting water availability through sap flow measurement in tree trunks, intrinsically accounting for drought and boundary layer effects on O{sub 3} flux. O{sub 3} uptake of evergreen spruce per unit foliage area was enhanced by 100% at high relative to low elevation, whereas deciduous beech and larch showed similar uptake regardless of altitude. The responsiveness of the canopy conductance to water vapor and, as a consequence, O{sub 3} uptake to soil moisture and air humidity did not differ between species. Unifying findings at the whole-tree level will promote cause-effect based O{sub 3} risk assessment and modeling. - Sap flow-based assessment of whole-tree O{sub 3} uptake reflects similar responsiveness of canopy conductance and O{sub 3} uptake across contrasting tree species and site conditions.

  11. Complex mountain terrain and disturbance history drive variation in forest aboveground live carbon density in the western Oregon Cascades, USA

    Science.gov (United States)

    Harold S.J. Zald; Thomas A. Spies; Rupert Seidl; Robert J. Pabst; Keith A. Olsen; Ashley Steel

    2016-01-01

    Forest carbon (C) density varies tremendously across space due to the inherent heterogeneity of forest ecosystems. Variation of forest C density is especially pronounced in mountainous terrain, where environmental gradients are compressed and vary at multiple spatial scales. Additionally, the influence of environmental gradients may vary with forest age and...

  12. Sensitivity of boreal forest regional water flux and net primary production simulations to sub-grid-scale land cover complexity

    Science.gov (United States)

    Kimball, J. S.; Running, S. W.; Saatchi, S. S.

    1999-11-01

    We use a general ecosystem process model (BIOME-BGC) coupled with remote sensing information to evaluate the sensitivity of boreal forest regional evapotranspiration (ET) and net primary production (NPP) to land cover spatial scale. Simulations were conducted over a 3 year period (1994-1996) at spatial scales ranging from 30 to 50 km within the BOREAS southern modeling subarea. Simulated fluxes were spatially complex, ranging from 0.1 to 3.9 Mg C ha-1 yr-1 and from 18 to 29 cm yr-1. Biomass and leaf area index heterogeneity predominantly controlled this complexity, while biophysical differences between deciduous and coniferous vegetation were of secondary importance. Spatial aggregation of land cover characteristics resulted in mean monthly NPP estimation bias from 25 to 48% (0.11-0.20 g C m-2 d-1) and annual estimation errors from 2 to 14% (0.04-0.31 Mg C ha-1 yr-1). Error was reduced at longer time intervals because coarse scale overestimation errors during spring were partially offset by underestimation of fine scale results during summer and winter. ET was relatively insensitive to land cover spatial scale with an average bias of less than 5% (0.04 kg m-2 d-1). Factors responsible for differences in scaling behavior between ET and NPP included compensating errors for ET calculations and boreal forest spatial and temporal NPP complexity. Careful consideration of landscape spatial and temporal heterogeneity is necessary to identify and mitigate potential error sources when using plot scale information to understand regional scale patterns. Remote sensing data integrated within an ecological process model framework provides an efficient mechanism to evaluate scaling behavior, interpret patterns in coarse resolution data, and identify appropriate scales of operation for various processes.

  13. Snowpack-atmosphere gas exchanges of carbon dioxide, ozone, and nitrogen oxides at a hardwood forest site in northern Michigan

    Directory of Open Access Journals (Sweden)

    Brian Seok

    2015-03-01

    Full Text Available Abstract Snowpack-atmosphere gas exchanges of CO2, O3, and NOx (NO + NO2 were investigated at the University of Michigan Biological Station (UMBS, a mid-latitude, low elevation hardwood forest site, during the 2007–2008 winter season. An automated trace gas sampling system was used to determine trace gas concentrations in the snowpack at multiple depths continuously throughout the snow-covered period from two adjacent plots. One natural plot and one with the soil covered by a Tedlar sheet were setup for investigating whether the primary source of measured trace gases was biogenic (i.e., from the soil or non-biogenic (i.e., from the snowpack. The results were compared with the “White on Green” study conducted at the Niwot Ridge (NWT Long Term Ecological Research site in Colorado. The average winter CO2 flux ± s.e. from the soil at UMBS was 0.54 ± 0.037 µmol m-2 s-1 using the gradient diffusion method and 0.71 ± 0.012 µmol m-2 s-1 using the eddy covariance method, and in a similar range as found for NWT. Observed snowpack-O3 exchange was also similar to NWT. However, nitrogen oxides (NOx fluxes from snow at UMBS were 10 times smaller than those at NWT, and fluxes were bi-directional with the direction of the flux dependent on NOx concentrations in ambient air. The compensation point for the change in the direction of NOx flux was estimated to be 0.92 nmol mol-1. NOx in snow also showed diurnal dependency on incident radiation. These NOx dynamics in the snow at UMBS were notably different compared to NWT, and primarily determined by snow-atmosphere interactions rather than by soil NOx emissions.

  14. H.T. Odum and the Luquillo Experimental Forest

    Science.gov (United States)

    Ariel E. Lugo

    2004-01-01

    How does the forest operate, develop its patterns, retain information in its memory sites, and transmit the great message to the future? (Odum, 1970a, p. x) The rain forest achieves complexity, high metabolism, and stability over geological time periods without surges and waste. Can we find in this example the clues for designing our own equally effective systems of...

  15. Evaluation of forest snow processes models (SnowMKIP2)

    Science.gov (United States)

    Nick Rutter; Richard Essery; John Pomeroy; Nuria Altimir; Kostas Andreadis; Ian Baker; Alan Barr; Paul Bartlett; Aaron Boone; Huiping Deng; Herve Douville; Emanuel Dutra; Kelly Elder; others

    2009-01-01

    Thirty-three snowpack models of varying complexity and purpose were evaluated across a wide range of hydrometeorological and forest canopy conditions at five Northern Hemisphere locations, for up to two winter snow seasons. Modeled estimates of snow water equivalent (SWE) or depth were compared to observations at forest and open sites at each location. Precipitation...

  16. Can Retention Harvest Maintain Natural Structural Complexity? A Comparison of Post-Harvest and Post-Fire Residual Patches in Boreal Forest

    Directory of Open Access Journals (Sweden)

    Louiza Moussaoui

    2016-10-01

    Full Text Available Variable retention harvest promotes biodiversity conservation in managed boreal forests by ensuring forest continuity and structural complexity. However, do post-harvest and post-fire patches maintain the same structural complexity? This study compares post-harvest and post-fire residual patches and proposes retention modalities that can maintain the same structural complexity as in natural forests, here considering both continuous forest stands and post-fire residual patches. In boreal black spruce forests, 41 post-fire residual patches, and 45 post-harvest retention patches of varying size and ages (exposure time to disturbed matrix and 37 continuous forest stands were classified into six diameter structure types. Types 1 (inverted-J and 2 (trunked-unimodal characterized stands dominated by small trees. The abundance of small trees decreased and the abundance of large trees increased from Type 1 to Type 6. Type 6 had the most irregular structure with a wide range of diameters. This study indicates that: (1 old post-harvest residual retentions maintained the range of structural complexity found in natural stands; (2 Types 1 and 2 were generally associated with young post-fire patches and post-harvest retention clumps; (3 the structure of residual patches containing only small trees was usually younger (in terms of the age of the original forest from which residual patches were formed than those with larger trees. To avoid the risk of simplifying the structure, retention patches should be intentionally oriented towards Types 3–6, dominated by intermediate and large trees.

  17. Wind Regimes above and below a Temperate Deciduous Forest Canopy in Complex Terrain: Interactions between Slope and Valley Winds

    Directory of Open Access Journals (Sweden)

    Xingchang Wang

    2014-12-01

    Full Text Available The thermally driven wind over mountainous terrains challenges the estimation of CO2 exchange between forests and the atmosphere when using the eddy covariance technique. In this study, the wind regimes were investigated in a temperate deciduous forested valley at the Maoershan site, Northeast China. The wind direction above the canopy was preferentially up-valley in the daytime and down-valley in the nighttime, corresponding to the diurnal patterns of above-canopy temperature gradient and stability parameter. In both leaf-on and -off nighttime, a down-valley flow with a maximum velocity of 1~3 m∙s−1 was often developed at 42 m above the ground (2.3-fold of the canopy height. However, the below-canopy prevailing wind was down-slope in the night, contrast to the below-canopy temperature lapse and unstable conditions. This substantial directional shear illustrated shallow slope winds were superimposed on larger-scale valley winds. As a consequence, the valley-wind component becomes stronger with increasing height, indicating a clear confluence of drainage flow to the valley center. In the daytime, the below-canopy wind was predominated down-slope due to the temperature inversion and stable conditions in the leaf-on season, and was mainly up-valley or down-slope in the leaf-off season. The isolation of momentum flux and radiation by the dense canopy played a key role in the formation of the below-canopy unaligned wind and inverse stability. Significant lateral kinematic momentum fluxes were detected due to the directional shear. These findings suggested a significant interaction between slope and valley winds at this site. The frequent vertical convergence / divergence above the canopy and horizontal divergence/convergence below the canopy in the nighttime / daytime is likely to induce significant advections of trace gases and energy flux.

  18. Modelling the carbon budget of intensive forest monitoring sites in Germany using the simulation model BIOME-BGC

    OpenAIRE

    Jochheim, H.; Puhlmann, M.; Beese, F.; Berthold, D.; Einert, P.; Kallweit, R.; Konopatzky, A.; Meesenburg, H.; Meiwes, K.-J.; Raspe, S.; Schulte-Bisping, H.; Schulz, C.

    2008-01-01

    It is shown that by calibrating the simulation model BIOME-BGC with mandatory and optional Level II data, within the ICP Forest programme, a well-founded calculation of the carbon budget of forest stands is achievable and, based on succeeded calibration, the modified BIOME-BGC model is a useful tool to assess the effect of climate change on forest ecosystems. peerReviewed

  19. Soil microbial biomass under pine forests in the north-western Spain: influence of stand age, site index and parent material

    Energy Technology Data Exchange (ETDEWEB)

    Mahia, J.; Perez-Ventura, L.; Cabaneiro, A.; Diaz-Ravina, M.

    2006-07-01

    The effects of stand age, site index and parent material on soil biochemical properties related to biomass (extractable C, microbial C and metabolic quotient) were examined in the 0-15 cm mineral soil layers of Pinus pinaster and Pinus sylvestris stand from NW Spain. Two productivity levels (low and high site index), two ages (young and old) and two parent soil materials (granite and acid schists) were considered. The data indicated that there were differences in microbial parameters in soils under different species. In general in P. pinaster forest higher values of biochemical parameters expressed on organic C basis, were observed in the stands of high site index as compared with the low ones; in contrast, in P. sylvestris no differences among stand site index were detected. In both species different results were also observed depending on parent material and a significant effect of stand age was detected for extractable C and microbial C in P. pinaster forest developed over granite. The data seem to indicate that measured parameters may have the potential to be used as indicators of the effect of forest management on soil organic matter quality. (Author) 25 refs.

  20. Withstanding a record drought: Dry season sap flow and safety margins of canopy epiphytes in three sites along an elevation gradient in a tropical montane cloud forest

    Science.gov (United States)

    Gotsch, S. G.; Darby, A.; Glunk, A.; Murray, J.; Draguljic, D.

    2016-12-01

    Tropical montane cloud forests (TMCFs) are projected to experience shifts in microclimate due to changes in precipitation patterns and cloud base heights. Understanding how the TMCF will be affected by such changes is critical since these forests harbor a great number of endemic species and the intact forest plays an important role in local and regional hydrology. The epiphyte community is one of the characteristic components of this unique ecosystem. Epiphytes contribute greatly to the biomass and diversity of the forest, and play an important role in the TMCF water cycle. The ecosystem role played by the epiphyte community may be lost if these species, which lack roots to the ground, cannot withstand projected changes in climate. We measured dry season sap flow in canopy epiphytes in three sites along an elevation gradient, in Monteverde Costa Rica during an extreme drought event. In addition, we measured predawn and midday leaf water potentials, and dry season pressure-volume curves on focal species. We found that during a month-long dry period, species in all sites reduced transpiration considerably, and for a two-week period, sap flow rates were close to zero. During this time, predawn and midday leaf water potentials remained high (> -1.0 MPa) due to the utilization of stored leaf water and strong stomatal regulation. At the end of the dry season, midday leaf water potentials were approximately 2x lower in the driest versus the wettest site (AVG: -0.94 vs. -0.47 MPa) although hydraulic safety margins were greater at the driest sites. Our results indicate that epiphyte communities vary in their water use strategies and that the epiphyte community in wetter sites is more likely to experience hydraulic failure if there are increases in the number of days without precipitation and/or increases in temperature.

  1. Growth dynamics of fine roots in a coniferous fern forest site close to Forsmark in the central part of Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Persson, Hans; Stadenberg, Ingela (SLU, Dept. of Ecology and Environmental Research, Uppsala (Sweden))

    2007-12-15

    The seasonal growth dynamics of live and dead roots for trees and the field layer species (g/m2, varying diameter fractions) and live/dead ratios were analysed at a fresh/moist coniferous fern forest site close to the nuclear power plant at Forsmark in the central eastern parts of Sweden. The changes in depth distribution of fine roots were observed at depth intervals of the top humus horizon down to 40 cm in the mineral soil profile. The bulk of living fine roots of trees (< 1 mm in diameter) were found in the mineral soil horizon the total profile down to 40 cm of the mineral soil, where 89, 82, 83 and 89% of the total amount in the whole profile were found. The upper 2.5 cm part of the humus layer contained 83, 81, 100 and 100% of all roots of the humus layer on the four different sampling occasions. High amounts of living fine roots were found in the upper 10 cm of the mineral soil horizon viz. 84, 76, 91 and 69% of the total mineral soil layer. Consequently, both the top soil horizons of the humus and the mineral soil layers were heavily penetrated by living fine roots. The highest proportion of living fine roots was found in the top 2.5 cm of the humus layer. Accordingly, the live/dead ratio of fine roots (< 1 mm in diameter) decreased from the top of the humus layer to the lower part of mineral soil horizon from 8.0-0.3, 0.8-0.2, 4.4-0.4 and 3.3-0.7 (g g-1) for the four sampling occasions, respectively. We concluded that the decrease in the live/ dead ratio was related to decreased vitality with depth of the fine roots in the soil profile. The highest live/dead ratio was found in the upper 2.5 cm of the humus layer for both the tree and field-layer species. This distribution pattern was most evident for tree fine roots < 1 mm in diameter. The mean fine-root biomass (live tissue < 1 mm in diameter) of tree species for the total profile varied on the four sampling occasions between 317, 113, 139 and 248 g m-2. The related fine root necromass (dead tissue

  2. Root water uptake model based on water potential gradient with water redistribution via roots: application to coniferous forest site

    Science.gov (United States)

    Votrubova, Jana; Vogel, Tomas; Dohnal, Michal; Dusek, Jaromir; Tesar, Miroslav

    2013-04-01

    A simple macroscopic vertically distributed plant root water uptake (RWU) model based on traditional water-potential-gradient formulation (Vogel et al., 2013), in which the uptake rates are directly proportional to the potential gradient and indirectly proportional to the local soil and root resistances to water flow, was tested. This RWU modeling approach was implemented in a one-dimensional dual-continuum model of soil water flow based on Richards' equation and used to simulate soil water distribution changes during a vegetation season at a forest site located in a temperate humid climate of central Europe. The main objectives were to test the ability of the presented RWU model to simulate the observed soil-plant-atmosphere interactions, and to examine the differences between empirical and more physically-based RWU modeling approaches (accommodated in the same soil water flow model). The tested RWU model was capable of simulating both the compensatory root water uptake, in situations when reduced uptake from dry layers was compensated for by increased uptake from wetter layers, and the root-mediated hydraulic redistribution of soil water, contributing to more natural soil moisture distribution throughout the root zone. Comparison of the model results with the sap flow observed reveals some limitations related to the quasi-steady-state assumption for the plant xylem and zero transpiration rates prescribed during nights and precipitation. This stated, the model seems to simulate adequately both the regular nightly hydraulic redistribution, due to reduced night transpiration, and the episodic daytime hydraulic redistribution during wet canopy events. The model results were compared to simulations produced using the semi-empirical RWU model of Feddes. Based on both an improved agreement between the observed and simulated soil water pressure responses to daily variations of transpiration, and a more realistic seasonal distribution of the transpiration rate reduction

  3. Underestimation of soil carbon stocks by Yasso07, Q, and CENTURY models in boreal forest linked to overlooking site fertility

    Science.gov (United States)

    Ťupek, Boris; Ortiz, Carina; Hashimoto, Shoji; Stendahl, Johan; Dahlgren, Jonas; Karltun, Erik; Lehtonen, Aleksi

    2016-04-01

    The soil organic carbon stock (SOC) changes estimated by the most process based soil carbon models (e.g. Yasso07, Q and CENTURY), needed for reporting of changes in soil carbon amounts for the United Nations Framework Convention on Climate Change (UNFCCC) and for mitigation of anthropogenic CO2 emissions by soil carbon management, can be biased if in a large mosaic of environments the models are missing a key factor driving SOC sequestration. To our knowledge soil nutrient status as a missing driver of these models was not tested in previous studies. Although, it's known that models fail to reconstruct the spatial variation and that soil nutrient status drives the ecosystem carbon use efficiency and soil carbon sequestration. We evaluated SOC stock estimates of Yasso07, Q and CENTURY process based models against the field data from Swedish Forest Soil National Inventories (3230 samples) organized by recursive partitioning method (RPART) into distinct soil groups with underlying SOC stock development linked to physicochemical conditions. These models worked for most soils with approximately average SOC stocks, but could not reproduce higher measured SOC stocks in our application. The Yasso07 and Q models that used only climate and litterfall input data and ignored soil properties generally agreed with two third of measurements. However, in comparison with measurements grouped according to the gradient of soil nutrient status we found that the models underestimated for the Swedish boreal forest soils with higher site fertility. Accounting for soil texture (clay, silt, and sand content) and structure (bulk density) in CENTURY model showed no improvement on carbon stock estimates, as CENTURY deviated in similar manner. We highlighted the mechanisms why models deviate from the measurements and the ways of considering soil nutrient status in further model development. Our analysis suggested that the models indeed lack other predominat drivers of SOC stabilization

  4. Palm bract breeding sites and their exploitation by Toxorhynchites (Lynchiella) haemorrhoidalis haemorrhoidalis (Diptera: Culicidae) in an upland forest of the central Amazon.

    Science.gov (United States)

    Hutchings, R S

    1994-03-01

    Considering the potential importance of Toxorhynchites (Lynchiella) haemorrhoidalis haemorrhoidalis (F.) as a biological control agent of other mosquitoes, this species was studied in an upland forest of the Central Amazon. Palm bracts, the natural breeding sites, were sampled monthly in two different study areas for a period of 1 yr to detect the presence of immature stages and to determine their capacity to recolonize new or empty bracts. The ability of these breeding sites (bracts) to retain water was greater on a plateau where there is less humidity than in a valley. The availability of breeding sites may be related to the number of existing palms and the low precipitation. Tx. h. haemorrhoidalis is multivoltine, and the greatest abundance of larvae occurred in natural breeding sites in the valley. The population fluctuations of the larvae of this species may be influenced by the availability of natural breeding sites and by low precipitation which occurs during the dry season.

  5. Interpreting participatory Fuzzy Cognitive Maps as complex networks in the social-ecological systems of the Amazonian forests

    Science.gov (United States)

    Varela, Consuelo; Tarquis, Ana M.; Blanco-Gutiérrez, Irene; Estebe, Paloma; Toledo, Marisol; Martorano, Lucieta

    2015-04-01

    Social-ecological systems are linked complex systems that represent interconnected human and biophysical processes evolving and adapting across temporal and spatial scales. In the real world, social-ecological systems pose substantial challenges for modeling. In this regard, Fuzzy Cognitive Maps (FCMs) have proven to be a useful method for capturing the functioning of this type of systems. FCMs are a semi-quantitative type of cognitive map that represent a system composed of relevant factors and weighted links showing the strength and direction of cause-effects relationships among factors. Therefore, FCMs can be interpreted as complex system structures or complex networks. In this sense, recent research has applied complex network concepts for the analysis of FCMs that represent social-ecological systems. Key to FCM the tool is its potential to allow feedback loops and to include stakeholder knowledge in the construction of the tool. Also, previous research has demonstrated their potential to represent system dynamics and simulate the effects of changes in the system, such as policy interventions. For illustrating this analysis, we have developed a series of participatory FCM for the study of the ecological and human systems related to biodiversity conservation in two case studies of the Amazonian region, the Bolivia lowlands of Guarayos and the Brazil Tapajos National forest. The research is carried out in the context of the EU project ROBIN1 and it is based on the development of a series of stakeholder workshops to analyze the current state of the socio-ecological environment in the Amazonian forest, reflecting conflicts and challenges for biodiversity conservation and human development. Stakeholders included all relevant actors in the local case studies, namely farmers, environmental groups, producer organizations, local and provincial authorities and scientists. In both case studies we illustrate the use of complex networks concepts, such as the adjacency

  6. Impact of Complex Orography on Wake Development: Simulation Results for the Planned WindForS Test Site

    Science.gov (United States)

    Lutz, Thorsten; Schulz, Christoph; Letzgus, Patrick; Rettenmeier, Andreas

    2017-05-01

    In Southern Germany a test site will be erected in complex terrain. The purpose is to enable detailed scientific studies of terrain impact on the characteristics of two research wind turbines and to demonstrate new technologies. Within preparatory studies an appropriate site was identified and examined by field tests and numerical studies in more detail. The present paper summarizes CFD analyses on the impact of the local test site orography on the wake development of a virtual wind turbine. The effects of the orography are identified by comparative simulations for the same turbine using comparative wind situation in flat terrain.

  7. Introduction to the Special Section--Bat Habitat Use in Eastern North American Temperate Forests: Site, Stand, an Landscape Effects

    Science.gov (United States)

    Robert T. Brooks; W. Mark Ford

    2006-01-01

    Forest bats of eastern North America select habitats for roosting, foraging, and winter hibernation/migration over a myriad of scales. An understanding of forest-bat habitat use over scales of time and space is important for their conservation and management. The papers in this Special Section report studies of bat habitat use across multiple scales from locations...

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

    Science.gov (United States)

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

    2014-01-01

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

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

    Science.gov (United States)

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

    2011-01-01

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

  10. Description of Some Ecological Factors in Three Forest Sites in Lorestan Province and Their Impact on Myrtle (Myrtus communis L. Essential Oil Yield and Chemical Components

    Directory of Open Access Journals (Sweden)

    Z. Mir-Azadi

    2013-03-01

    Full Text Available Due to the side effects of chemical drugs, special attention is given recently to pharmaceutical plants. Myrtle (Myrtus communis L. is one of the valuable pharmaceutical plants, which is distributed over the vast areas of Iran. Yield and components of essential oil of this plant is dependent on ecological and genetic factors. In order to describe some ecological factors that affect myrtle in Lorestan province, three forest sites (Sepiddasht, Chame-moord, and Hamzeh Camp were selected. Some effective ecological factors on type of essential oil were measured and compared among the sites. To compare the yield and components of essential oil, myrtle leaves were collected during flowering stage in each site. Leaves were dried in open air conditions and the oil was extracted by distillation. Yield of essential oil was calculated and its components were identified by GC and GC/MS. Results showed that maximum yield belongs to Sepiddasht site. The altitude and soil Na, P, and organic carbon content of this site is quite different from other two sites. The main components of essential oils of these three sites had considerable differences. The amount of 9,10 anthracenedione was 29.1% in Sepiddasht site, while it was not found in the oil of Chame-moord site. It seems that differences in ecological and soil properties of the tree sites could have major effect on essential oil yield and its composition.

  11. Remote Sensing Assessment of Forest Disturbance across Complex Mountainous Terrain: The Pattern and Severity of Impacts of Tropical Cyclone Yasi on Australian Rainforests

    Directory of Open Access Journals (Sweden)

    Robinson I. Negrón-Juárez

    2014-06-01

    Full Text Available Topography affects the patterns of forest disturbance produced by tropical cyclones. It determines the degree of exposure of a surface and can alter wind characteristics. Whether multispectral remote sensing data can sense the effect of topography on disturbance is a question that deserves attention given the multi-scale spatial coverage of these data and the projected increase in intensity of the strongest cyclones. Here, multispectral satellite data, topographic maps and cyclone surface wind data were used to study the patterns of disturbance in an Australian rainforest with complex mountainous terrain produced by tropical cyclone Yasi (2011. The cyclone surface wind data (H*wind was produced by the Hurricane Research Division of the National Oceanic and Atmospheric Administration (HRD/NOAA, and this was the first time that this data was produced for a cyclone outside of United States territory. A disturbance map was obtained by applying spectral mixture analyses on satellite data and presented a significant correlation with field-measured tree mortality. Our results showed that, consistent with cyclones in the southern hemisphere, multispectral data revealed that forest disturbance was higher on the left side of the cyclone track. The highest level of forest disturbance occurred in forests along the path of the cyclone track (±30°. Levels of forest disturbance decreased with decreasing slope and with an aspect facing off the track of the cyclone or away from the dominant surface winds. An increase in disturbance with surface elevation was also observed. However, areas affected by the same wind intensity presented increased levels of disturbance with increasing elevation suggesting that complex terrain interactions act to speed up wind at higher elevations. Yasi produced an important offset to Australia’s forest carbon sink in 2010. We concluded that multispectral data was sensitive to the main effects of complex topography on disturbance

  12. High Fat Diet Enhances β-Site Cleavage of Amyloid Precursor Protein (APP via Promoting β-Site APP Cleaving Enzyme 1/Adaptor Protein 2/Clathrin Complex Formation.

    Directory of Open Access Journals (Sweden)

    Masato Maesako

    Full Text Available Obesity and type 2 diabetes are risk factors of Alzheimer's disease (AD. We reported that a high fat diet (HFD promotes amyloid precursor protein (APP cleavage by β-site APP cleaving enzyme 1 (BACE1 without increasing BACE1 levels in APP transgenic mice. However, the detailed mechanism had remained unclear. Here we demonstrate that HFD promotes BACE1/Adaptor protein-2 (AP-2/clathrin complex formation by increasing AP-2 levels in APP transgenic mice. In Swedish APP overexpressing Chinese hamster ovary (CHO cells as well as in SH-SY5Y cells, overexpression of AP-2 promoted the formation of BACE1/AP-2/clathrin complex, increasing the level of the soluble form of APP β (sAPPβ. On the other hand, mutant D495R BACE1, which inhibits formation of this trimeric complex, was shown to decrease the level of sAPPβ. Overexpression of AP-2 promoted the internalization of BACE1 from the cell surface, thus reducing the cell surface BACE1 level. As such, we concluded that HFD may induce the formation of the BACE1/AP-2/clathrin complex, which is followed by its transport of BACE1 from the cell surface to the intracellular compartments. These events might be associated with the enhancement of β-site cleavage of APP in APP transgenic mice. Here we present evidence that HFD, by regulation of subcellular trafficking of BACE1, promotes APP cleavage.

  13. High Fat Diet Enhances β-Site Cleavage of Amyloid Precursor Protein (APP) via Promoting β-Site APP Cleaving Enzyme 1/Adaptor Protein 2/Clathrin Complex Formation.

    Science.gov (United States)

    Maesako, Masato; Uemura, Maiko; Tashiro, Yoshitaka; Sasaki, Kazuki; Watanabe, Kiwamu; Noda, Yasuha; Ueda, Karin; Asada-Utsugi, Megumi; Kubota, Masakazu; Okawa, Katsuya; Ihara, Masafumi; Shimohama, Shun; Uemura, Kengo; Kinoshita, Ayae

    2015-01-01

    Obesity and type 2 diabetes are risk factors of Alzheimer's disease (AD). We reported that a high fat diet (HFD) promotes amyloid precursor protein (APP) cleavage by β-site APP cleaving enzyme 1 (BACE1) without increasing BACE1 levels in APP transgenic mice. However, the detailed mechanism had remained unclear. Here we demonstrate that HFD promotes BACE1/Adaptor protein-2 (AP-2)/clathrin complex formation by increasing AP-2 levels in APP transgenic mice. In Swedish APP overexpressing Chinese hamster ovary (CHO) cells as well as in SH-SY5Y cells, overexpression of AP-2 promoted the formation of BACE1/AP-2/clathrin complex, increasing the level of the soluble form of APP β (sAPPβ). On the other hand, mutant D495R BACE1, which inhibits formation of this trimeric complex, was shown to decrease the level of sAPPβ. Overexpression of AP-2 promoted the internalization of BACE1 from the cell surface, thus reducing the cell surface BACE1 level. As such, we concluded that HFD may induce the formation of the BACE1/AP-2/clathrin complex, which is followed by its transport of BACE1 from the cell surface to the intracellular compartments. These events might be associated with the enhancement of β-site cleavage of APP in APP transgenic mice. Here we present evidence that HFD, by regulation of subcellular trafficking of BACE1, promotes APP cleavage.

  14. Multiple active site conformers in the carbon monoxide complexes of trematode hemoglobins.

    Science.gov (United States)

    Das, Tapan K; Dewilde, Sylvia; Friedman, Joel M; Moens, Luc; Rousseau, Denis L

    2006-04-28

    Sequence alignment of hemoglobins of the trematodes Paramphistomum epiclitum and Gastrothylax crumenifer with myoglobin suggests the presence of an unusual active site structure in which two tyrosine residues occupy the E7 and B10 helical positions. In the crystal structure of P. epiclitum hemoglobin, such an E7-B10 tyrosine pair at the putative helical positions has been observed, although the E7 Tyr is displaced toward CD region of the polypeptide. Resonance Raman data on both P. epiclitum and G. crumenifer hemoglobins show that interactions of heme-bound ligands with neighboring amino acid residues are unusual. Multiple conformers in the CO complex, termed the C, O, and N conformers, are observed. The conformers are separated by a large difference (approximately 60 cm(-1)) in the frequencies of their Fe-CO stretching modes. In the C conformer the Fe-CO stretching frequency is very high, 539 and 535 cm(-1), for the P. epiclitum and G. crumenifer hemoglobins, respectively. The Fe-CO stretching of the N conformer appears at an unusually low frequency, 479 and 476 cm(-1), respectively, for the two globins. A population of an O conformer is seen in both hemoglobins, at 496 and 492 cm(-1), respectively. The C conformer is stabilized by a strong polar interaction of the CO with the distal B10 tyrosine residue. The O conformer is similar to the ones typically seen in mutant myoglobins in which there are no strong interactions between the CO and residues in the distal pocket. The N conformer possesses an unusual configuration in which a negatively charged group, assigned as the oxygen atom of the B10 Tyr side chain, interacts with the CO. In this conformer, the B10 Tyr assumes an alternative conformation consistent with one of the conformers seen the crystal structure. Implications of the multiple configurations on the ligand kinetics are discussed.

  15. Nitrogen mineralization and nitrification in a mixed-conifer forest in southern California: controlling factors, fluxes, and nitrogen fertilization response at a high and low nitrogen deposition site

    Science.gov (United States)

    Mark E. Fenn; Mark A. Poth; Joseph D. Terry; Timothy J. Blubaugh

    2005-01-01

    Net fluxes of nitrogen (N) mineralization and nitrification were measured in situ on a monthly basis for 3 years at a high (HN) and low (LN) N deposition site in the San Bernardino Mountains, California. Mean N mineralization fluxes in the forest floor and top 10 cm of mineral soil were 19.0 and 59.8 kg N·ha–1·year–1 at LN...

  16. From genotype to phenotype: unraveling the complexities of cold adaptation in forest trees

    Science.gov (United States)

    Glenn T. Howe; Sally N. Aitken; David B. Neale; Kathleen D. Jermstad; Nicholas C. Wheeler; Tony H.H Chen

    2003-01-01

    Adaptation to winter cold in temperate and boreal trees involves complex genetic, physiological, and developmental processes. Genecological studies demonstrate the existence of steep genetic clines for cold adaptation traits in relation to environmental (mostly temperature related) gradients. Population differentiation is generally stronger for cold adaptation traits...

  17. The Trees and the Forest : Characterization of complex brain networks with minimum spanning trees

    NARCIS (Netherlands)

    Stam, C.J.; Tewarie, P.; Van Dellen, E.; Van Straaten, E.C.W.; Hillebrand, A.; Van Mieghem, P.

    2014-01-01

    In recent years there has been a shift in focus from the study of local, mostly task-related activation to the exploration of the organization and functioning of large-scale structural and functional complex brain networks. Progress in the interdisciplinary field of modern network science has

  18. The trees and the forest: Characterization of complex brain networks with minimum spanning trees

    NARCIS (Netherlands)

    Stam, C.J.; Tewarie, P.; van Dellen, E.; van Straaten, E.C.W.; Hillebrand, A.; Van Mieghem, P.

    2014-01-01

    In recent years there has been a shift in focus from the study of local, mostly task-related activation to the exploration of the organization and functioning of large-scale structural and functional complex brain networks. Progress in the interdisciplinary field of modern network science has

  19. When is a biogeochemical model too complex? Objective model reduction and selection for North Atlantic time-series sites

    Science.gov (United States)

    Ward, Ben A.; Schartau, Markus; Oschlies, Andreas; Martin, Adrian P.; Follows, Michael J.; Anderson, Thomas R.

    2013-09-01

    The degree of structural complexity that should be incorporated in marine biogeochemical models is unclear. We know that the marine ecosystem is complex, and that its observed behaviour is attributable to the interaction of a large number of separate processes, but observations are scarce and often insufficient to constrain more than a small number of model parameters. This issue is addressed using a novel algorithm that systematically removes model processes that are not constrained by observations. The algorithm is applied to a one-dimensional, eight component ecosystem-biogeochemistry model at two North Atlantic time-series sites. Between 11 and 14 of the 30 model parameters can be removed at each site with no significant reduction in the model’s ability to fit upper ocean (0-200 m) biogeochemical tracer and productivity data. The statistically optimal model structures and parameters provide estimates of the most likely state variables and fluxes at each site. Differences in these estimates between the two sites indicate that the optimal models are specialised to both the physical environment and the assimilated observations. At each site the heavily reduced models may thus be suitable for diagnostic purposes but may not be sufficiently complex for more general applications, such as in global ocean general circulation models, or for predicting the response of marine systems to environmental change.

  20. Soil data for a thermokarst bog and the surrounding permafrost plateau forest, located at Bonanza Creek Long Term Ecological Research Site, Interior Alaska

    Science.gov (United States)

    Manies, Kristen L.; Fuller, Christopher C.; Jones, Miriam C.; Waldrop, Mark P.; McGeehin, John P.

    2017-01-19

    Peatlands play an important role in boreal ecosystems, storing a large amount of soil organic carbon. In northern ecosystems, collapse-scar bogs (also known as thermokarst bogs) often form as the result of ground subsidence following permafrost thaw. To examine how ecosystem carbon balance changes with the loss of permafrost, we measured carbon and nitrogen storage within a thermokarst bog and the surrounding forest, which continues to have permafrost. These sites are a part of the Bonanza Creek Long Term Ecological Research (LTER) site and are located within Interior Alaska. Here, we report on methods used for core collection analysis as well as the cores’ physical, chemical, and descriptive properties.

  1. Composition and seasonal phenology of a nonindigenous root-feeding weevil (Coleoptera: Curculionidae) complex in northern hardwood forests in the Great Lakes Region

    Science.gov (United States)

    R. A. Pinski; W. J. Mattson; K. F. Raffa

    2005-01-01

    Phyllobius oblongus (L.), Polydrusus sericeus (Schaller), and Sciaphilus asperatus (Bonsdorff) comprise a complex of nonindigenous root-feeding weevils in northern hardwood forests of the Great Lakes region. Little is known about their detailed biology, seasonality, relative abundance, and distribution patterns....

  2. Genetic variation in a tropical tree species influences the associated epiphytic plant and invertebrate communities in a complex forest ecosystem.

    Science.gov (United States)

    Zytynska, Sharon E; Fay, Michael F; Penney, David; Preziosi, Richard F

    2011-05-12

    Genetic differences among tree species, their hybrids and within tree species are known to influence associated ecological communities and ecosystem processes in areas of limited species diversity. The extent to which this same phenomenon occurs based on genetic variation within a single tree species, in a diverse complex ecosystem such as a tropical forest, is unknown. The level of biodiversity and complexity of the ecosystem may reduce the impact of a single tree species on associated communities. We assessed the influence of within-species genetic variation in the tree Brosimum alicastrum (Moraceae) on associated epiphytic and invertebrate communities in a neotropical rainforest. We found a significant positive association between genetic distance of trees and community difference of the epiphytic plants growing on the tree, the invertebrates living among the leaf litter around the base of the tree, and the invertebrates found on the tree trunk. This means that the more genetically similar trees are host to more similar epiphyte and invertebrate communities. Our work has implications for whole ecosystem conservation management, since maintaining sufficient genetic diversity at the primary producer level will enhance species diversity of other plants and animals.

  3. Temperate mountain forest biodiversity under climate change: compensating negative effects by increasing structural complexity.

    Science.gov (United States)

    Braunisch, Veronika; Coppes, Joy; Arlettaz, Raphaël; Suchant, Rudi; Zellweger, Florian; Bollmann, Kurt

    2014-01-01

    Species adapted to cold-climatic mountain environments are expected to face a high risk of range contractions, if not local extinctions under climate change. Yet, the populations of many endothermic species may not be primarily affected by physiological constraints, but indirectly by climate-induced changes of habitat characteristics. In mountain forests, where vertebrate species largely depend on vegetation composition and structure, deteriorating habitat suitability may thus be mitigated or even compensated by habitat management aiming at compositional and structural enhancement. We tested this possibility using four cold-adapted bird species with complementary habitat requirements as model organisms. Based on species data and environmental information collected in 300 1-km2 grid cells distributed across four mountain ranges in central Europe, we investigated (1) how species' occurrence is explained by climate, landscape, and vegetation, (2) to what extent climate change and climate-induced vegetation changes will affect habitat suitability, and (3) whether these changes could be compensated by adaptive habitat management. Species presence was modelled as a function of climate, landscape and vegetation variables under current climate; moreover, vegetation-climate relationships were assessed. The models were extrapolated to the climatic conditions of 2050, assuming the moderate IPCC-scenario A1B, and changes in species' occurrence probability were quantified. Finally, we assessed the maximum increase in occurrence probability that could be achieved by modifying one or multiple vegetation variables under altered climate conditions. Climate variables contributed significantly to explaining species occurrence, and expected climatic changes, as well as climate-induced vegetation trends, decreased the occurrence probability of all four species, particularly at the low-altitudinal margins of their distribution. These effects could be partly compensated by modifying

  4. Temperate mountain forest biodiversity under climate change: compensating negative effects by increasing structural complexity.

    Directory of Open Access Journals (Sweden)

    Veronika Braunisch

    Full Text Available Species adapted to cold-climatic mountain environments are expected to face a high risk of range contractions, if not local extinctions under climate change. Yet, the populations of many endothermic species may not be primarily affected by physiological constraints, but indirectly by climate-induced changes of habitat characteristics. In mountain forests, where vertebrate species largely depend on vegetation composition and structure, deteriorating habitat suitability may thus be mitigated or even compensated by habitat management aiming at compositional and structural enhancement. We tested this possibility using four cold-adapted bird species with complementary habitat requirements as model organisms. Based on species data and environmental information collected in 300 1-km2 grid cells distributed across four mountain ranges in central Europe, we investigated (1 how species' occurrence is explained by climate, landscape, and vegetation, (2 to what extent climate change and climate-induced vegetation changes will affect habitat suitability, and (3 whether these changes could be compensated by adaptive habitat management. Species presence was modelled as a function of climate, landscape and vegetation variables under current climate; moreover, vegetation-climate relationships were assessed. The models were extrapolated to the climatic conditions of 2050, assuming the moderate IPCC-scenario A1B, and changes in species' occurrence probability were quantified. Finally, we assessed the maximum increase in occurrence probability that could be achieved by modifying one or multiple vegetation variables under altered climate conditions. Climate variables contributed significantly to explaining species occurrence, and expected climatic changes, as well as climate-induced vegetation trends, decreased the occurrence probability of all four species, particularly at the low-altitudinal margins of their distribution. These effects could be partly compensated

  5. Modeling complex equilibria in isothermal titration calorimetry experiments: thermodynamic parameters estimation for a three-binding-site model.

    Science.gov (United States)

    Le, Vu H; Buscaglia, Robert; Chaires, Jonathan B; Lewis, Edwin A

    2013-03-15

    Isothermal titration calorimetry (ITC) is a powerful technique that can be used to estimate a complete set of thermodynamic parameters (e.g., K(eq) (or ΔG), ΔH, ΔS, and n) for a ligand-binding interaction described by a thermodynamic model. Thermodynamic models are constructed by combining equilibrium constant, mass balance, and charge balance equations for the system under study. Commercial ITC instruments are supplied with software that includes a number of simple interaction models, for example, one binding site, two binding sites, sequential sites, and n-independent binding sites. More complex models, for example, three or more binding sites, one site with multiple binding mechanisms, linked equilibria, or equilibria involving macromolecular conformational selection through ligand binding, need to be developed on a case-by-case basis by the ITC user. In this paper we provide an algorithm (and a link to our MATLAB program) for the nonlinear regression analysis of a multiple-binding-site model with up to four overlapping binding equilibria. Error analysis demonstrates that fitting ITC data for multiple parameters (e.g., up to nine parameters in the three-binding-site model) yields thermodynamic parameters with acceptable accuracy. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. Quality control of CarboEurope flux data - Part 1: Coupling footprint analyses with flux data quality assessment to evaluate sites in forest ecosystems

    DEFF Research Database (Denmark)

    Göckede, M.; Foken, T.; Aubinet, M.

    2008-01-01

    We applied a site evaluation approach combining Lagrangian Stochastic footprint modeling with a quality assessment approach for eddy-covariance data to 25 forested sites of the CarboEurope-IP network. The analysis addresses the spatial representativeness of the flux measurements, instrumental...... effects on data quality, spatial patterns in the data quality, and the performance of the coordinate rotation method. Our findings demonstrate that application of a footprint filter could strengthen the CarboEurope-IP flux database, since only one third of the sites is situated in truly homogeneous...... terrain. Almost half of the sites experience a significant reduction in eddy-covariance data quality under certain conditions, though these effects are mostly constricted to a small portion of the dataset. Reductions in data quality of the sensible heat flux are mostly induced by characteristics...

  7. Reduced-complexity multi-site rainfall generation: one million years over night using the model TripleM

    Science.gov (United States)

    Breinl, Korbinian; Di Baldassarre, Giuliano; Girons Lopez, Marc

    2017-04-01

    We assess uncertainties of multi-site rainfall generation across spatial scales and different climatic conditions. Many research subjects in earth sciences such as floods, droughts or water balance simulations require the generation of long rainfall time series. In large study areas the simulation at multiple sites becomes indispensable to account for the spatial rainfall variability, but becomes more complex compared to a single site due to the intermittent nature of rainfall. Weather generators can be used for extrapolating rainfall time series, and various models have been presented in the literature. Even though the large majority of multi-site rainfall generators is based on similar methods, such as resampling techniques or Markovian processes, they often become too complex. We think that this complexity has been a limit for the application of such tools. Furthermore, the majority of multi-site rainfall generators found in the literature are either not publicly available or intended for being applied at small geographical scales, often only in temperate climates. Here we present a revised, and now publicly available, version of a multi-site rainfall generation code first applied in 2014 in Austria and France, which we call TripleM (Multisite Markov Model). We test this fast and robust code with daily rainfall observations from the United States, in a subtropical, tropical and temperate climate, using rain gauge networks with a maximum site distance above 1,000km, thereby generating one million years of synthetic time series. The modelling of these one million years takes one night on a recent desktop computer. In this research, we first start the simulations with a small station network of three sites and progressively increase the number of sites and the spatial extent, and analyze the changing uncertainties for multiple statistical metrics such as dry and wet spells, rainfall autocorrelation, lagged cross correlations and the inter-annual rainfall

  8. Mineralogical siting of platinum-group elements in pentlandite from the Bushveld Complex, South Africa

    Science.gov (United States)

    Junge, Malte; Wirth, Richard; Oberthür, Thomas; Melcher, Frank; Schreiber, Anja

    2015-01-01

    The Bushveld Complex in South Africa hosts the world's largest resources of platinum-group elements (PGEs), which are mainly mined from three ore bodies, namely the Merensky Reef, the UG-2 chromitite, and the Platreef. In these ores, the PGEs are bimodally distributed, occurring both as discrete platinum-group minerals (PGMs) and hosted by sulfides. The presence of PGEs in sulfides has been demonstrated by electron probe microanalysis, laser ablation induced coupled plasma mass spectrometry, secondary ion mass spectrometry, and particle-induced X-ray emission. However, evidence is lacking on the mineralogical siting of the PGEs, e.g., whether they occur in solid solution, as nano-inclusions, and/or micro-inclusions. Therefore, in the present study, a combination of focused ion beam and transmission electron microscopy was used which allows to obtain crystal structural relationships between the host mineral and incorporated trace elements and revealing the physicochemical state of the PGE in sulfides. The present study confirms the existence of micrometer-sized discrete PGMs in the ores. Further, the PGEs occur in a number of forms, namely (1) as discrete nano-inclusions of PGMs, (2) as patchily distributed solid solution, (3) ordered within the pentlandite crystal structure, substituting for Ni and/or Fe (superlattice), and (4) as homogenous solid solution. Nanometer-sized PGMs (nPGMs) show no orientation relationship with the host sulfide mineral. Consequently, they are discrete phases, which were trapped within pentlandite during sulfide growth. Heterogeneous and patchy distributions of Rh and Ir within the pentlandite lattice suggest that Rh and Ir were already present within the sulfide liquid. The absence of possible reaction partners (e.g., Bi, As, and Sn) necessary for the formation of discrete PGMs forced Rh and Ir to remain in the crystal lattice of pentlandite and down-temperature exsolution caused patchy distribution patterns of Rh and Ir. High

  9. LBA-ECO CD-10 H2O Profiles at km 67 Tower Site, Tapajos National Forest

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains a single text file which reports vertical profiles of H2O vapor concentrations measured at the Para Western (Santarem) - km 67, Primary Forest...

  10. LBA-ECO TG-07 Ground-based Biometry Data at km 83 Site, Tapajos National Forest: 1997

    Data.gov (United States)

    National Aeronautics and Space Administration — A field inventory of trees was conducted in March of 1997 in a logging concession at the Tapajos National Forest, south of Santarem, Para, Brazil. The inventory was...

  11. Crystal structure of the bacterial ribosomal decoding site complexed with amikacin containing the gamma-amino-alpha-hydroxybutyryl (haba) group.

    Science.gov (United States)

    Kondo, Jiro; François, Boris; Russell, Rupert J M; Murray, James B; Westhof, Eric

    2006-08-01

    Amikacin is the 4,6-linked aminoglycoside modified at position N1 of the 2-deoxystreptamine ring (ring II) by the L-haba group. In the present study, the crystal structure of a complex between oligonucleotide containing the bacterial ribosomal A site and amikacin has been solved at 2.7 A resolution. Amikacin specifically binds to the A site in practically the same way as its parent compound kanamycin. In addition, the L-haba group interacts with the upper side of the A site through two direct contacts, O2*...H-N4(C1496) and N4*-H...O6(G1497). The present crystal structure shows how the introduction of the L-haba group on ring II of aminoglycoside is an effective mutation for obtaining a higher affinity to the bacterial A site.

  12. Crystal Structure of a Bacterial Topoisomerase IB in Complex with DNA Reveals a Secondary DNA Binding Site

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Asmita; Yakovleva, Lyudmila; Shuman, Stewart; Mondragón, Alfonso (NWU); (SKI)

    2010-10-22

    Type IB DNA topoisomerases (TopIB) are monomeric enzymes that relax supercoils by cleaving and resealing one strand of duplex DNA within a protein clamp that embraces a {approx}21 DNA segment. A longstanding conundrum concerns the capacity of TopIB enzymes to stabilize intramolecular duplex DNA crossovers and form protein-DNA synaptic filaments. Here we report a structure of Deinococcus radiodurans TopIB in complex with a 12 bp duplex DNA that demonstrates a secondary DNA binding site located on the surface of the C-terminal domain. It comprises a distinctive interface with one strand of the DNA duplex and is conserved in all TopIB enzymes. Modeling of a TopIB with both DNA sites suggests that the secondary site could account for DNA crossover binding, nucleation of DNA synapsis, and generation of a filamentous plectoneme. Mutations of the secondary site eliminate synaptic plectoneme formation without affecting DNA cleavage or supercoil relaxation.

  13. Condition of forest ecosystems in the zone of aerial emissions’ impact of the Norilsk mining and metallurgical industrial complex. First communication

    Directory of Open Access Journals (Sweden)

    R. A. Ziganshin

    2017-06-01

    Full Text Available In the study, based on the analysis of literary sources and the own research materials, the characteristic of the environmental situation in Taimyr is done, in connection with aerial technogenic impact of the Norilsk mining and metallurgical industrial complex. The dynamics of forest condition over the past decade in the area close to 200 km or more from the plant were evaluated. The analysis was performed taking into account the landscape structure of the territory. The progressive drying of the large areas of the northern forests since the early 80 is registered. In the article, according to the literature reviewed, the structure, dynamics and distribution of air industrial emissions of the Norilsk mining and metallurgical industrial complex «Norilsk Nickel» is analyzed and presented. Further, the authors considered the impact of air industrial emissions of Norilsk industrial region on the forest ecosystems of Taimyr. The focus is on the main forest-forming tree – Siberian larch Larix sibirica Ledeb. It is noted the complete absence of the larch undergrowth in the area of industrial pollution. Investigation of the technogenically damaged forests was carried out on the basis of dendrochronological research at six different points on different distances from the city of Norilsk, mainly to the south and east of the metallurgical plant. One study point (sparse larch community is located 5 km north-west of Norilsk. We investigated stands of varying degrees of damage, including completely dead. It is shown, that outside the area of Norilsk mining and metallurgical industrial complex impact there were no signs of damage to the foliage of the trees and on the contrary, in the area of air pollution (Khantaiskoe Lake, forest stands are largely affected. The main damaging agent is sulfur dioxide.

  14. Characterisation of Beaver Habitat Parameters That Promote the Use of Culverts as Dam Construction Sites: Can We Limit the Damage to Forest Roads?

    Directory of Open Access Journals (Sweden)

    Geneviève Tremblay

    2017-12-01

    Full Text Available The use of forest roads as foundations for dam construction by beavers is a recurrent problem in the management of forest road networks. In order to limit the damage to forest roads, our goal was to calculate the probability of beaver dam installation on culverts, according to surrounding habitat parameters, which could allow for improvement in the spatial design of new roads that minimise conflicts with beavers. Comparisons of culverts with (n = 77 and without (n = 51 dams in northwestern Quebec showed that catchment surface, cumulate length of all local streams within a 2-km radius, and road embankment height had a negative effect on the probability of dam construction on culverts, while flow level and culvert diameter ratio had a positive effect. Nevertheless, predicted probabilities of dam construction on culverts generally exceeded 50%, even on sites that were less favourable to beavers. We suggest that it would be more reasonable to take their probable subsequent presence into account at the earliest steps of road conception. Installing mitigation measures such as pre-dams during road construction would probably reduce the occurrence of conflicts with beavers and thus reduce the maintenance costs of forest roads.

  15. Inhibitors of ROS production by the ubiquinone-binding site of mitochondrial complex I identified by chemical screening

    Science.gov (United States)

    Orr, Adam L.; Ashok, Deepthi; Sarantos, Melissa R.; Shi, Tong; Hughes, Robert E.; Brand, Martin D.

    2013-01-01

    Mitochondrial production of reactive oxygen species is often considered an unavoidable consequence of aerobic metabolism and currently cannot be manipulated without perturbing oxidative phosphorylation. Antioxidants are widely used to suppress effects of reactive oxygen species after formation, but they can never fully prevent immediate effects at the sites of production. To identify site-selective inhibitors of mitochondrial superoxide/H2O2 production that do not interfere with mitochondrial energy metabolism, we developed a robust small-molecule screen and secondary profiling strategy. We describe the discovery and characterization of a compound (N-cyclohexyl-4-(4-nitrophenoxy)benzenesulfonamide; CN-POBS) that selectively inhibits superoxide/H2O2 production from the ubiquinone-binding site of complex I (site IQ) with no effects on superoxide/H2O2 production from other sites or on oxidative phosphorylation. Structure/activity studies identified a core structure that is important for potency and selectivity for site IQ. By employing CN-POBS in mitochondria respiring on NADH-generating substrates, we show that site IQ does not produce significant amounts of superoxide/H2O2 during forward electron transport on glutamate plus malate. Our screening platform promises to facilitate further discovery of direct modulators of mitochondrially-derived oxidative damage and advance our ability to understand and manipulate mitochondrial reactive oxygen species production in both normal and pathological conditions. PMID:23994103

  16. Complex Analysis of the Stone Inventory from the Chashkinskoe Ozero XI Mesolithic Site

    Directory of Open Access Journals (Sweden)

    Mitroshin Evgeny N.

    2017-09-01

    Full Text Available Chashkinskoe Ozero XI site is a new Mesolithic monument on the eastern shore of the lake. A homogeneous inventory discovered at its excavations allowed to identify the site as a temporary hunter settlement. The authors of research conducted typological, technological and traceological analyses of the site inventory. It was determined by technological analysis that the stone industry of the site was characterized by controlled knapping with the predominant use of chopping tools and reduction of the platform edge as the primary technique of platform formation. No initial knapping was conducted at the site, and the nuclei were supplied to the site in ready form. Other features of the stone industry are as follows: high level of the blade production , small dimensions of blanks, availability of implements with various shapes, leading role of meat/fish knives and significant role of solid material cutters. The characteristic features of the collection include the absence of cores and a small amount of production waste. Almost half of discovered items have been used as implements. The results of this study can be used in further research of the Mesolithic of the Kama region as a pattern for this type of sites.

  17. Complex Terrain and Wind Lidars

    DEFF Research Database (Denmark)

    Bingöl, Ferhat

    This thesis includes the results of a PhD study about complex terrain and wind lidars. The study mostly focuses on hilly and forested areas. Lidars have been used in combination with cups, sonics and vanes, to reach the desired vertical measurement heights. Several experiments are performed...... in complex terrain sites and the measurements are compared with two different flow models; a linearised flow model LINCOM and specialised forest model SCADIS. In respect to the lidar performance in complex terrain, the results showed that horizontal wind speed errors measured by a conically scanning lidar...... models and the comparison of the measurement data with the flow model outputs showed that the mean wind speed calculated by LINCOM model was only reliable between 1 and 2 tree height (h) above canopy. The SCADIS model reported better correlation with the measurements in forest up to ∼6h. At the forest...

  18. Nest site characteristics of the Great-spotted Woodpecker in a bottomland riparian forest in the presence of invasive tree species

    Directory of Open Access Journals (Sweden)

    Ónodi Gábor

    2016-06-01

    Full Text Available This study was carried out in Hungary, in an old unmanaged riparian poplar-willow forest during the breeding seasons of 2014 and 2015. The occurrence of two invasive tree species, the green ash and boxelder, is significant in the study area, which influences negatively the populations of native riparian tree species in Central Europe. We studied Great-spotted Woodpecker nest sites in the presence of these invasive species. Throughout the study period, eight and twelve nesting cavity trees were mapped. Trees were recorded in 20-20 circular plots of 0.05 ha both for each mapped nest trees and random plots as well. Species, diameter at breast height and condition were recorded for each tree. Composition and diversity of nest site and random plots were compared. Distributions and preferences were calculated for nest tree use. Most of the recorded trees were invasive. Nest site plots had more native trees compared to random plots. Nest site showed higher diversity in terms of all three variables. Decayed and dead willow and white poplar hybrid trees were preferred for nesting. Diameter at breast height of nest trees was between 30-90 cm. Studies about cavity excavators in transformed habitats have high importance for nature conservation of riparian forests.

  19. Process-Based Modeling to Assess the Effects of Recent Climatic Variation on Site Productivity and Forest Function across Western North America

    Directory of Open Access Journals (Sweden)

    Richard H. Waring

    2014-03-01

    Full Text Available A process-based forest growth model, 3-PG (Physiological Principles Predicting Growth, parameterized with values of soil properties constrained by satellite-derived estimates of maximum leaf area index (LAImax, was run for Douglas-fir (Pseudotsuga menziesii to contrast the extent to which site growth potential might vary across western North America between a cool, wet period (1950–1975 and a more recent, generally warmer and drier one (2000–2009. LAImax represents a surrogate for overall site growth potential, as demonstrated from a strong correlation between the two variables, with the latter based on the culmination of mean annual increment estimates made at 3356 ground-based U.S. Forest Service survey plots across the states of Oregon and Washington. Results indicate that since 2000, predicted LAImax has decreased more than 20% in portions of the Southwest USA and for much of the forested area in western Alberta. Similar percentage increases in LAImax were predicted for parts of British Columbia, Idaho and Montana. The modeling analysis included an assessment of changes in seasonal constraints on gross primary production (GPP. A general reduction in limitations caused by spring frost occurred across the entire study area. This has led to a longer growing season, along with notable increases in summer evaporative demand and soil drought for much of the study area away from the maritime influence of the Pacific Ocean.

  20. Transition metal diphenolate and dithiophenolate complexes as synthetic analogues of the active sites of nickel superoxide dismutase and galactose oxidase

    OpenAIRE

    Marshall, George

    2016-01-01

    This thesis describes the synthesis of diphenolate and dithiophenolate complexes of ZnII, NiII and CuII that derive inspiration from the natures of the active sites of the nickel-containing superoxide dismutase (NiSOD) and the copper-containing galactose oxidase (GO).\\ud Chapter One introduces the roles of transition metals in biology. The structures of the active sites of NiSOD and GO are described, together with a discussion of the proposed mechanisms of their action. A brief review of the ...

  1. Metal Ion Binding at the Catalytic Site Induces Widely Distributed Changes in a Sequence Specific Protein-DNA Complex.

    Science.gov (United States)

    Sinha, Kaustubh; Sangani, Sahil S; Kehr, Andrew D; Rule, Gordon S; Jen-Jacobson, Linda

    2016-11-08

    Metal ion cofactors can alter the energetics and specificity of sequence specific protein-DNA interactions, but it is unknown if the underlying effects on structure and dynamics are local or dispersed throughout the protein-DNA complex. This work uses EcoRV endonuclease as a model, and catalytically inactive lanthanide ions, which replace the Mg 2+ cofactor. Nuclear magnetic resonance (NMR) titrations indicate that four Lu 3+ or two La 3+ cations bind, and two new crystal structures confirm that Lu 3+ binding is confined to the active sites. NMR spectra show that the metal-free EcoRV complex with cognate (GATATC) DNA is structurally distinct from the nonspecific complex, and that metal ion binding sites are not assembled in the nonspecific complex. NMR chemical shift perturbations were determined for 1 H- 15 N amide resonances, for 1 H- 13 C Ile-δ-CH 3 resonances, and for stereospecifically assigned Leu-δ-CH 3 and Val-γ-CH 3 resonances. Many chemical shifts throughout the cognate complex are unperturbed, so metal binding does not induce major conformational changes. However, some large perturbations of amide and side chain methyl resonances occur as far as 34 Å from the metal ions. Concerted changes in specific residues imply that local effects of metal binding are propagated via a β-sheet and an α-helix. Both amide and methyl resonance perturbations indicate changes in the interface between subunits of the EcoRV homodimer. Bound metal ions also affect amide hydrogen exchange rates for distant residues, including a distant subdomain that contacts DNA phosphates and promotes DNA bending, showing that metal ions in the active sites, which relieve electrostatic repulsion between protein and DNA, cause changes in slow dynamics throughout the complex.

  2. Metal Ion Binding at the Catalytic Site Induces Widely Distributed Changes in a Sequence Specific Protein–DNA Complex

    Science.gov (United States)

    2016-01-01

    Metal ion cofactors can alter the energetics and specificity of sequence specific protein–DNA interactions, but it is unknown if the underlying effects on structure and dynamics are local or dispersed throughout the protein–DNA complex. This work uses EcoRV endonuclease as a model, and catalytically inactive lanthanide ions, which replace the Mg2+ cofactor. Nuclear magnetic resonance (NMR) titrations indicate that four Lu3+ or two La3+ cations bind, and two new crystal structures confirm that Lu3+ binding is confined to the active sites. NMR spectra show that the metal-free EcoRV complex with cognate (GATATC) DNA is structurally distinct from the nonspecific complex, and that metal ion binding sites are not assembled in the nonspecific complex. NMR chemical shift perturbations were determined for 1H–15N amide resonances, for 1H–13C Ile-δ-CH3 resonances, and for stereospecifically assigned Leu-δ-CH3 and Val-γ-CH3 resonances. Many chemical shifts throughout the cognate complex are unperturbed, so metal binding does not induce major conformational changes. However, some large perturbations of amide and side chain methyl resonances occur as far as 34 Å from the metal ions. Concerted changes in specific residues imply that local effects of metal binding are propagated via a β-sheet and an α-helix. Both amide and methyl resonance perturbations indicate changes in the interface between subunits of the EcoRV homodimer. Bound metal ions also affect amide hydrogen exchange rates for distant residues, including a distant subdomain that contacts DNA phosphates and promotes DNA bending, showing that metal ions in the active sites, which relieve electrostatic repulsion between protein and DNA, cause changes in slow dynamics throughout the complex. PMID:27786446

  3. Crystal structure of vinculin in complex with vinculin binding site 50 (VBS50), the integrin binding site 2 (IBS2) of talin

    Energy Technology Data Exchange (ETDEWEB)

    Yogesha, S.D.; Rangarajan, Erumbi S.; Vonrhein, Clemens; Bricogne, Gerard; Izard, Tina (Globel Phasing); (Scripps)

    2012-05-10

    The cytoskeletal protein talin activates integrin receptors by binding of its FERM domain to the cytoplasmic tail of {beta}-integrin. Talin also couples integrins to the actin cytoskeleton, largely by binding to and activating the cytoskeletal protein vinculin, which binds to F-actin through the agency of its five-helix bundle tail (Vt) domain. Talin activates vinculin by means of buried amphipathic {alpha}-helices coined vinculin binding sites (VBSs) that reside within numerous four- and five-helix bundle domains that comprise the central talin rod, which are released from their buried locales by means of mechanical tension on the integrin:talin complex. In turn, these VBSs bind to the N-terminal seven-helix bundle (Vh1) domain of vinculin, creating an entirely new helix bundle that severs its head-tail interactions. Interestingly, talin harbors a second integrin binding site coined IBS2 that consists of two five-helix bundle domains that also contain a VBS (VBS50). Here we report the crystal structure of VBS50 in complex with vinculin at 2.3 {angstrom} resolution and show that intramolecular interactions of VBS50 within IBS2 are much more extensive versus its interactions with vinculin. Indeed, the IBS2-vinculin interaction only occurs at physiological temperature and the affinity of VBS50 for vinculin is about 30 times less than other VBSs. The data support a model where integrin binding destabilizes IBS2 to allow it to bind to vinculin.

  4. Site-selective detection of vibrational modes of an iron atom in a trinuclear complex

    Energy Technology Data Exchange (ETDEWEB)

    Faus, Isabelle, E-mail: faus@rhrk.uni-kl.de; Rackwitz, Sergej; Wolny, Juliusz A. [University of Kaiserslautern, Department of Physics (Germany); Banerjee, Atanu; Kelm, Harald; Krüger, Hans-Jörg [University of Kaiserslautern, Department of Chemistry (Germany); Schlage, Kai; Wille, Hans-Christian [DESY, PETRA III, P01 (Germany); Schünemann, Volker [University of Kaiserslautern, Department of Physics (Germany)

    2016-12-15

    Nuclear inelastic scattering (NIS) experiments on the trinuclear complex [{sup 57}Fe{L-N_4(CH_2Fc)_2} (CH{sub 3}CN){sub 2}](ClO{sub 4}){sub 2} have been performed. The octahedral iron ion in the complex was labelled with {sup 57}Fe and thereby exclusively the vibrational modes of this iron ion have been detected with NIS. The analysis of nuclear forward scattering (NFS) data yields a ferrous low-spin state for the {sup 57}Fe labelled iron ion. The simulation of the partial density of states (pDOS) for the octahedral low-spin iron(II) ion of the complex by density functional theory (DFT) calculations is in excellent agreement with the experimental pDOS of the complex determined from the NIS data obtained at 80 K. Thereby it was possible to assign almost each of the experimentally observed NIS bands to the corresponding molecular vibrational modes.

  5. Improving Independent Student Navigation of Complex Educational Web Sites: An Analysis of Two Navigation Design Changes in LibGuides

    OpenAIRE

    Pittsley, Kate A; Sara Memmott

    2012-01-01

    Can the navigation of complex research web sites be improved so that users more often find their way without intermediation or instruction?  Librarians at Eastern Michigan University discovered that students were not recognizing navigational elements on web based research guides and tested possible solutions. In this study, two types of navigation improvements were applied to separate sets of online guides. Both sets of experimental guides showed an increase in use of navigation to secondary ...

  6. How to Commission, Operate and Maintain a Large Future Accelerator Complex From Far Remote Sites

    CERN Document Server

    Czarapata, P C; Myers, S; Peggs, S; Phinney, N; Serio, M; Toge, N; Willeke, F; Zhang, C

    2001-01-01

    A study on future large accelerators [1] has considered a facility, which is designed, built and operated by a worldwide collaboration of equal partner institutions, and which is remote from most of these institutions. The full range of operation was considered including commissioning, machine development, maintenance, troubleshooting and repair. Experience from existing accelerators confirms that most of these activities are already performed 'remotely'. The large high-energy physics experiments and astronomy projects, already involve international collaborations of distant institutions. Based on this experience, the prospects for a machine operated remotely from far sites are encouraging. Experts from each laboratory would remain at their home institution but continue to participate in the operation of the machine after construction. Experts are required to be on site only during initial commissioning and for particularly difficult problems. Repairs require an on-site non-expert maintenance crew. Most of th...

  7. Populations of Clethrionomys glareolus in three isolated forest complexes in rural southern Moravia (Czech Republic

    Directory of Open Access Journals (Sweden)

    Josef Suchomel

    2006-09-01

    Full Text Available Abstract In rural landscapes, the dynamics of bank vole (Clethrionomys glareolus populations were studied from 2002 to 2005 in three large isolated forest complexes which differed in tree composition and food supply. Populations fluctuated markedly during the four years of research. Extra seed crop in 2003 and probable niche vacation - the density of the dominant Apodemus flavicollis lowered in 2004 -, determined two years (2004-05 of higher bank vole population densities. The relative abundance of C. glareolus was higher in the most variable biotope (RB, consisting of an intensive pheasantry. Also the body mass of adult individuals, particularly females, was higher in RB. The influence of seed crop on the weight of individuals was statistically significant. During winter 2004/2005 a strong impact on the forest regeneration in tree plantings was reported. We argue that vole abundance prediction by periodical monitoring is needed to prevent damage. Riassunto Popolazioni di Clethrionomys glareolus in tre complessi forestali di un’area agricola della Moravia meridionale (Repubblica Ceca La dinamica di popolazione di C. glareolus è stata indagata in tre complessi forestali relitti in ambiente rurale, differenti sia per aspetti vegetazionali sia riguardo la disponibilità di risorse alimentari. L’abbondanza relativa (rA dell’arvicola rossastra ha mostrato ampie oscillazioni nei tre siti, in parte da ricollegare a una produzione eccezionale di ghiande nell’autunno 2003 e a un decremento di A. flavicollis (specie dominante nel 2004, che hanno determinato due anni consecutivi (2004-05 di rA elevate per C. glareolus. Nel complesso, i valori di rA sono risultati maggiori nel biotopo più diversificato, così come anche la massa corporea degli adulti, in particolare delle femmine. La produzione di semi del 2003 ha anche influito

  8. Multiple complex odontomas and subsequent occurrence of an ossifying fibroma at the same site as the removed odontoma

    Directory of Open Access Journals (Sweden)

    Kou Matsuo

    2013-06-01

    Full Text Available We report a rare case of multiple complex odontomas and the subsequent occurrence of an ossifying fibroma at the same site as one of the removed odontomas. A 3-year-old Japanese boy presented three complex odontomas at the unerupted deciduous first and second molars and permanent first molar on the left side of the mandible. The two odontomas at the deciduous teeth were immediately extirpated, and, after 2 years of follow-up, the odontoma at the unerupted permanent first molar was removed. At the age of 7 years, a small odontoma surrounding the deciduous second molar emerged as a recurrence. When the patient was 9 years old, an ossifying fibroma occurred near the apex of the first premolar, i.e., the site where one of the original odontomas existed. Furthermore, a small radiopaque mass over the crown of the unerupted permanent second molar was observed at the age of 10 years; this mass was probably an additional fourth complex odontoma. This is not only a rare case report of ossifying fibroma associated with multiple complex odontomas but also a valuable time course observation of the development of such odontogenic tumors.

  9. Economic and environmental optimization of a multi-site utility network for an industrial complex.

    Science.gov (United States)

    Kim, Sang Hun; Yoon, Sung-Geun; Chae, Song Hwa; Park, Sunwon

    2010-01-01

    Most chemical companies consume a lot of steam, water and electrical resources in the production process. Given recent record fuel costs, utility networks must be optimized to reduce the overall cost of production. Environmental concerns must also be considered when preparing modifications to satisfy the requirements for industrial utilities, since wastes discharged from the utility networks are restricted by environmental regulations. Construction of Eco-Industrial Parks (EIPs) has drawn attention as a promising approach for retrofitting existing industrial parks to improve energy efficiency. The optimization of the utility network within an industrial complex is one of the most important undertakings to minimize energy consumption and waste loads in the EIP. In this work, a systematic approach to optimize the utility network of an industrial complex is presented. An important issue in the optimization of a utility network is the desire of the companies to achieve high profits while complying with the environmental regulations. Therefore, the proposed optimization was performed with consideration of both economic and environmental factors. The proposed approach consists of unit modeling using thermodynamic principles, mass and energy balances, development of a multi-period Mixed Integer Linear Programming (MILP) model for the integration of utility systems in an industrial complex, and an economic/environmental analysis of the results. This approach is applied to the Yeosu Industrial Complex, considering seasonal utility demands. The results show that both the total utility cost and waste load are reduced by optimizing the utility network of an industrial complex. 2009 Elsevier Ltd. All rights reserved.

  10. An infrastructure for flexible use - complex architecture and technical installations at the ETH Hoenggerberg site; Flexibel nutzbare Infrastruktur

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, C. M.

    2002-07-01

    This article describes the new extension to the Swiss Federal Institute of Technology's (ETH) facilities at its Hoenggerberg site near Zurich. The glass and metal facade structure with integrated lamellas that provide shading and control of the heat throughput through the facade is described and the complex supply of technical services for a building complex that houses laboratories, auditoriums, libraries, teaching rooms and canteen facilities is discussed. Further systems, such as a solar power installation on the roof and the central control and monitoring system for building technical services are described. A table presents figures on the building complex, which will ultimately provide around 2,300 places for work and education.

  11. Land-use history affects understorey plant species distributions in a large temperate-forest complex, Denmark

    DEFF Research Database (Denmark)

    Svenning, J.-C.; Baktoft, Karen H.; Balslev, Henrik

    2009-01-01

    historical factors were also important. The pure historical variation fraction constituted 13% of the variation explained. The RDA results showed that ancient-forest status and, secondarily, reclaimed bog status were the only significant historical variables. Many typical forest interior species, with poor...

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

    Science.gov (United States)

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

    2014-01-01

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

  13. Surface complexation modeling of U(VI) adsorption by aquifer sediments from a former mill tailings site at Rifle, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Hyun, S. P.; Fox, Patricia M.; Davis, James A.; Campbell, Kate M.; Hayes, Kim F.; Long, Philip E.

    2009-12-15

    U(VI) adsorption by two aquifer sediment samples was studied under oxic conditions as a function of pH, U(VI), Ca, and dissolved carbonate concentration. Background-A (BKG-A) sediment was collected upstream of a former uranium mill-tailings site at Rifle, Colorado, and Little Rusty Composite (LRC) was collected on site but with low U contamination. Batch adsorption experiments were performed using artificial groundwater solutions prepared to simulate the field groundwater composition in equilibrium with specific partial pressures of carbon dioxide. To encompass the geochemical conditions of the alluvial aquifer at the site, the experimental conditions ranged from 6.8×10-8 to 10-5 M in [U(VI)]tot, 7.2 to 8.0 in pH, 3.0×10-3 to 6.0×10-3 M in [Ca2+], and 0.05 to 2.6% in partial pressure of carbon dioxide. The sediment was extracted with a dilute bicarbonate/carbonate solution to determine the background labile U(VI) already present in the sediment. A semi-empirical surface complexation model was developed to describe U(VI) adsorption using FITEQL4. The non-electrostatic, generalized composite surface complexation model successfully simulated U(VI) adsorption over the range of groundwater conditions at the Old Rifle site, using a two-site, two-reaction fitting scheme. The sensitivity of model parameters to background U(VI) concentration on the two samples was evaluated. U(VI) adsorption experiments were also performed using a sand fraction of BKG-A separated through repeated sonication and wet-sieving. Surface area normalized Kd for the bulk and sand fraction indicated similar reactivity for both. The surface complexation model developed in this work is expected to contribute to the prediction of fate and transport of U(VI) in the alluvial aquifer at the Old Rifle site, and to assist in the simulation of biostimulation field experiments performed at the site.

  14. Nitrogen mineralization and nitrification in a mixed-conifer forest in southern California : controlling factors, fluxes, and nitrogen fertilization response at a high and low nitrogen deposition site

    Energy Technology Data Exchange (ETDEWEB)

    Fenn, M.E.; Poth, M.A.; Terry, J.D.; Blubaugh, T.J. [United States Dept. of Agriculture, Riverside, CA (United States). Forest Service, Pacific Southwest Research Station

    2005-06-01

    Human activities and anthropogenic emissions have disturbed the global nitrogen (N) cycle to the point that atmospheric deposition of inorganic nitrogen has increased nearly threefold above preindustrial levels. These increased levels have the potential to cause excessive nitrogen enrichment of aquatic and terrestrial ecosystems. Increased nitrogen levels stimulate nitrogen mineralization and nitrification, thereby contributing to mobilization of nitrogen and nitrogen saturation conditions. In this study, net fluxes of nitrogen mineralization and nitrification were measured in situ on a monthly basis for 3 years in the San Bernardino Mountains in California. The objective was to quantify the rates of net nitrogen mineralization and nitrification in the humus layer and mineral soil under field conditions in fertilized and unfertilized plots at a nitrogen deposition forest site that is highly N saturated as well as a low nitrogen deposition site to determine whether relative nitrification patterns in field assays are similar to laboratory study results. The main factors affecting nitrogen cycling rates in the mineral soil and the forest floor were determined. The study also tested the hypothesis that slow release nitrogen fertilization over 3 years at a low nitrogen site results in net nitrification rates that approach those of high nitrogen sites. The study revealed the relative nitrification rates under different tree canopies. The key factor for predicting the rate of net nitrification is the rate of net nitrogen mineralization. A high nitrogen fertilization had no substantial impact on net nitrification. It was concluded that at low-deposition sites, increased nitrification occurs in the short term due to added nitrogen. However, the accumulation of nitrogen enriched litter and soil organic matter along with chronic throughfall nitrogen deposition causes sustained elevated net nitrification. 67 refs., 7 tabs., 7 figs.

  15. Occupancy and Functional Architecture of the Pigment Binding Sites of Photosystem II Antenna Complex Lhcb5

    NARCIS (Netherlands)

    Ballottari, Matteo; Mozzo, Milena; Croce, Roberta; Morosinotto, Tomas; Bassi, Roberto

    2009-01-01

    Lhcb5 is an antenna protein that is highly conserved in plants and green algae. It is part of the inner layer of photosystem II antenna system retained in high light acclimated plants. To study the structure-function relation and the role of individual pigments in this complex, we (i) "knocked out"

  16. Pigment binding sites occupancy and functional architecture of the Photosystem II antenna complex Lhcb5

    NARCIS (Netherlands)

    Ballottari, M.; Mozzo, M.; Croce, R.; Morosinotto, T.; Bassi, R.

    2009-01-01

    Lhcb5 is an antenna protein that is highly conserved in plants and green algae. It is part of the inner layer of photosystem II antenna system retained in high light acclimated plants. To study the structure-function relation and the role of individual pigments in this complex, we (i) "knocked out"

  17. Insulator protein Su(Hw) recruits SAGA and Brahma complexes and constitutes part of Origin Recognition Complex-binding sites in the Drosophila genome

    Science.gov (United States)

    Vorobyeva, Nadezhda E.; Mazina, Marina U.; Golovnin, Anton K.; Kopytova, Daria V.; Gurskiy, Dmitriy Y.; Nabirochkina, Elena N.; Georgieva, Sofia G.; Georgiev, Pavel G.; Krasnov, Aleksey N.

    2013-01-01

    Despite increasing data on the properties of replication origins, molecular mechanisms underlying origin recognition complex (ORC) positioning in the genome are still poorly understood. The Su(Hw) protein accounts for the activity of best-studied Drosophila insulators. Here, we show that Su(Hw) recruits the histone acetyltransferase complex SAGA and chromatin remodeler Brahma to Su(Hw)-dependent insulators, which gives rise to regions with low nucleosome density and creates conditions for ORC binding. Depletion in Su(Hw) leads to a dramatic drop in the levels of SAGA, Brahma and ORC subunits and a significant increase in nucleosome density on Su(Hw)-dependent insulators, whereas artificial Su(Hw) recruitment itself is sufficient for subsequent SAGA, Brahma and ORC binding. In contrast to the majority of replication origins that associate with promoters of active genes, Su(Hw)-binding sites constitute a small proportion (6%) of ORC-binding sites that are localized preferentially in transcriptionally inactive chromatin regions termed BLACK and BLUE chromatin. We suggest that the key determinants of ORC positioning in the genome are DNA-binding proteins that constitute different DNA regulatory elements, including insulators, promoters and enhancers. Su(Hw) is the first example of such a protein. PMID:23609538

  18. High resolution digital elevation modelling from TLS and UAV campaign reveals structural complexity at the 2014 Holuhraun eruption site

    Science.gov (United States)

    Müller, Daniel; Walter, Thomas R.; Titt, Tanja; Schöpa, Anne; Tumi Gudmundsson, Magnus; Dürig, Tobi

    2017-04-01

    Fissure eruptions are commonly linked to magma dikes at depth, associated with deformation that is described by subsidence and lateral widening at the surface. The structure formation associated with such fissure eruptions, however, is barely preserved in nature because of the rapid erosion and/or difficult access to these areas, which is why, so far, normal fault displacements are commonly assumed for this type of fractures. At the 2014 Holuhraun eruption sites, the largest fissure eruption in Iceland since almost two centuries, evidence is increasing that the developing structures are related to pre-existing topography, reactivation of earlier fractures and possible complexity in the opening mode of the dike. In an attempt to investigate the Holuhraun structures in greater detail, a fieldwork mapping project combining terrestrial laser scanning (TLS) and unmanned aerial vehicle (UAV) based aerophoto analysis was realized. From this data, we generated a locally high resolution digital elevation model and a structural map that allow for identification of kinematic indicators and assessing senses of fault opening, strike-slip movements, and complexities in fracture pathways. We identified fracture curvatures, step-overs and en-echelon type structures, and measured strike directions for single fault segments including the amount of opening and opening angles. We conjecture that local complexities in the fracture paths and fracture geometries are closely related to pre-existing geometric and mechanical heterogeneities. Moreover, we identified local changes in fracture trends and offsets close to eruption sites, which are possibly associated with geometrical changes in the feeding dike itself. Results have important implications for the development of surface structures at fissure eruption sites and underline that the structural memory is a very important factor in understanding the complexities of local fault structures above dike intrusions.

  19. Indices of onchocerciasis transmission by different members of the Simulium damnosum complex conflict with the paradigm of forest and savanna parasite strains.

    Science.gov (United States)

    Cheke, Robert A; Garms, Rolf

    2013-01-01

    Onchocerciasis in savanna zones is generally more severe than in the forest and pathologies also differ geographically, differences often ascribed to the existence of two or more strains and incompatibilities between vectors and strains. However, flies in the forest transmit more infective larvae than their savanna counterparts, even in sympatry, contradicting expectations based on the forest and savanna strains paradigm. We analysed data on the numbers of Onchocerca volvulus larvae of different stages found in 10 different taxonomic categories of the Simulium damnosum complex derived from more than 48,800 dissections of flies from Sierra Leone in the west of Africa to Uganda in the east. The samples were collected before widespread ivermectin distribution and thus provide a baseline for evaluating control measures. Savanna species contained fewer larvae per infected or per infective fly than the forest species, even when biting and parous rates were accounted for. The highest transmission indices were found in the forest-dwelling Pra form of Simulium sanctipauli (616 L3/1000 parous flies) and the lowest in the savanna-inhabiting species S. damnosum/S. sirbanum (135) and S. kilibanum (65). Frequency distributions of numbers of L1-2 and L3 larvae found in parous S. damnosum/S. sirbanum, S. kilibanum, S. squamosum, S. yahense, S. sanctipauli, S. leonense and S. soubrense all conformed to the negative binomial distribution, with the mainly savanna-dwelling species (S. damnosum/S. sirbanum) having less overdispersed distributions than the mainly forest-dwelling species. These infection patterns were maintained even when forest and savanna forms were sympatric and biting the same human population. Furthermore, for the first time, levels of blindness were positively correlated with infection intensities of the forest vector S. yahense, consistent with relations previously reported for savanna zones. Another novel result was that conversion rates of L1-2 larvae to L3s

  20. Simultaneous dual vascular access site for the treatment of coronary artery bifurcation lesions by complex 2-stent technique.

    Science.gov (United States)

    Isaaz, Karl; Mayaud, Norbert; Lamaud, Michel; Raynaud, Amélie; Cerisier, Alexis; Sabry, Mohammed Hassan; Richard, Laure; Khamis, Hazem; Abd-Alaziz, Ahmad; DA Costa, Antoine

    2012-10-01

    To propose an original approach based on simultaneous dual vascular access site (DAS) using 2 small-size guiding catheters to easily perform complex 2-stent techniques for bifurcation coronary lesions (BL). Simultaneous kissing stenting and classic crush technique require large 7 or 8Fr guiding catheters leading to large amounts of contrast medium, vascular access site complications, and sometimes frictions or criss-cross of the 2-stent delivery systems. DAS was used in 30 patients with BL (11 radio-radial, 16 radio-femoral, and 3 femoro-femoral). Among 60 guiding catheters, the size was 5Fr in 28, 6Fr in 30, and 7Fr in 2 cases of double adjacent BL. When 2 different size catheters were used, contrast medium injections were done using the smallest size catheter. DAS patients were compared with a group of 30 BL patients treated using a single femoral vascular access site (SAS) with 7 or 8Fr catheters. Success rate was 100% in all patients. Contrast volume used was smaller in DAS than in SAS patients (277 ± 156 cc vs. 380 ± 165 cc,P = 0.01). No vascular access site complication occurred in the sub-group of the 11 DAS radio-radial patients. Postintervention hospitalization duration was shorter in DAS than in SAS (1.9 ± 2 vs. 2.8 ± 2 days,P = 0.048). DAS allows to successfully perform complex stenting technique of BL using small-size guiding catheters leading to decreased contrast medium volume, decreased vascular access site complications rates, and shortened hospitalization duration. ©2012, Wiley Periodicals, Inc.

  1. History and stabilization of the Plutonium Finishing Plant (PFP) complex, Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Gerber, M.S., Fluor Daniel Hanford

    1997-02-18

    The 231-Z Isolation Building or Plutonium Metallurgy Building is located in the Hanford Site`s 200 West Area, approximately 300 yards north of the Plutonium Finishing Plant (PFP) (234-5 Building). When the Hanford Engineer Works (HEW) built it in 1944 to contain the final step for processing plutonium, it was called the Isolation Building. At that time, HEW used a bismuth phosphate radiochemical separations process to make `AT solution,` which was then dried and shipped to Los Alamos, New Mexico. (AT solution is a code name used during World War II for the final HEW product.) The process was carried out first in T Plant and the 224-T Bulk Reduction Building and B Plant and the 224-B Bulk Reduction Building. The 224-T and -B processes produced a concentrated plutonium nitrate stream, which then was sent in 8-gallon batches to the 231-Z Building for final purification. In the 231-Z Building, the plutonium nitrate solution underwent peroxide `strikes` (additions of hydrogen peroxide to further separate the plutonium from its carrier solutions), to form the AT solution. The AT solution was dried and shipped to the Los Alamos Site, where it was made into metallic plutonium and then into weapons hemispheres.` The 231-Z Building began `hot` operations (operations using radioactive materials) with regular runs of plutonium nitrate on January 16, 1945.

  2. Uncommon Implantation Sites of Ectopic Pregnancy: Thinking beyond the Complex Adnexal Mass.

    Science.gov (United States)

    Chukus, Anjeza; Tirada, Nikki; Restrepo, Ricardo; Reddy, Neelima I

    2015-01-01

    Ectopic pregnancy occurs when implantation of the blastocyst takes place in a site other than the endometrium of the uterine cavity. Uncommon implantation sites of ectopic pregnancy include the cervix, interstitial segment of the fallopian tube, scar from a prior cesarean delivery, uterine myometrium, ovary, and peritoneal cavity. Heterotopic and twin ectopic pregnancies are other rare manifestations. Ultrasonography (US) plays a central role in diagnosis of uncommon ectopic pregnancies. US features of an interstitial ectopic pregnancy include an echogenic interstitial line and abnormal bulging of the myometrial contour. A gestational sac that is located below the internal os of the cervix and that contains an embryo with a fetal heartbeat is indicative of a cervical ectopic pregnancy. In a cesarean scar ectopic pregnancy, the gestational sac is implanted in the anterior lower uterine segment at the site of the cesarean scar, with thinning of the myometrium seen anterior to the gestational sac. An intramural gestational sac implants in the uterine myometrium, separate from the uterine cavity and fallopian tubes. In an ovarian ectopic pregnancy, a gestational sac with a thick hyperechoic circumferential rim is located in or on the ovarian parenchyma. An intraperitoneal gestational sac is present in an abdominal ectopic pregnancy. Intra- and extrauterine gestational sacs are seen in a heterotopic pregnancy. Two adnexal heartbeats suggest a live twin ectopic pregnancy. Recognition of the specific US features will help radiologists diagnose these uncommon types of ectopic pregnancy. (©)RSNA, 2015.

  3. Competition between injunctive social norms and conservation priorities gives rise to complex dynamics in a model of forest growth and opinion dynamics.

    Science.gov (United States)

    Sigdel, Ram P; Anand, Madhur; Bauch, Chris T

    2017-11-07

    Human and environmental systems are often treated as existing in isolation from one another, whereas in fact they are often two parts of a single, coupled human-environment system. Developing theoretical models of coupled human-environment systems is a continuing area of research, although relatively few of these models are based on differential equations. Here we develop a simple differential equation coupled human-environment system model of forest growth dynamics and conservationist opinion dynamics in a human population. The model assumes logistic growth and harvesting in the forest. Opinion spread in the human population is based on the interplay between conservation values stimulated by forest rarity, and injunctive social norms that tend to support population conformity. We find that injunctive social norms drive the system to the boundaries of phase space, whereas rarity-based conservation priorities drive the system to the interior. The result is complex dynamics including limit cycles and alternative stable states that do not occur if injunctive social norms are absent. We found that the model with injunctive social norms had five possible observable outcomes, whereas the model without social norms had only two stable states. Thus social norms and have dramatic influence in conservation dynamics. We also find that increasing the conservation value of forests is the best way to boost and stabilize forest cover while also boosting conservationist opinion in the population, although for some parameter regimes it can also give rise to long-term oscillations in opinions and forest cover. We conclude that simple models can provide insights and reveal patterns that might be difficult to see with high-dimensional computational models, and therefore should be used more often in research on coupled human-environment systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Multi-Drug Resistant Surgical Site Infection Due to Mycobacterium abscessus Complex.

    Science.gov (United States)

    Misra, Richa; Jain, Vidhi; Tejan, Nidhi; Negi, Aarti; Umrao, Jyoti; Dhole, Tapan Nirodhechand

    2017-08-01

    M. abscessus complex is notoriously resistant to most antimicrobial agents. The complex is differentiated into 3 subspecies: M. abscessus subsp. abscessus, M. abscessus subsp. massiliense, and M. abscessus subsp. bolletii. Skin and soft tissue infections due to this organism can be acquired by direct contact with contaminated material through traumatic injury, surgical wound and environmental exposure or by secondary involvement of skin/soft tissue during disseminated disease. We report a case of Mycobacterium abscessus infection recovered from a post-operative mid-line abdominal wound to illustrate the diagnostic and management difficulties encountered in such patients. © American Society for Clinical Pathology, 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  5. A real-time view of the TAR:Tat:P-TEFb complex at HIV-1 transcription sites

    Directory of Open Access Journals (Sweden)

    Knezevich Anna

    2007-05-01

    Full Text Available Abstract HIV-1 transcription is tightly regulated: silent in long-term latency and highly active in acutely-infected cells. Transcription is activated by the viral protein Tat, which recruits the elongation factor P-TEFb by binding the TAR sequence present in nascent HIV-1 RNAs. In this study, we analyzed the dynamic of the TAR:Tat:P-TEFb complex in living cells, by performing FRAP experiments at HIV-1 transcription sites. Our results indicate that a large fraction of Tat present at these sites is recruited by Cyclin T1. We found that in the presence of Tat, Cdk9 remained bound to nascent HIV-1 RNAs for 71s. In contrast, when transcription was activated by PMA/ionomycin, in the absence of Tat, Cdk9 turned-over rapidly and resided on the HIV-1 promoter for only 11s. Thus, the mechanism of trans-activation determines the residency time of P-TEFb at the HIV-1 gene, possibly explaining why Tat is such a potent transcriptional activator. In addition, we observed that Tat occupied HIV-1 transcription sites for 55s, suggesting that the TAR:Tat:P-TEFb complex dissociates from the polymerase following transcription initiation, and undergoes subsequent cycles of association/dissociation.

  6. Atomistic determinants of co-enzyme Q reduction at the Qi-site of the cytochrome bc1 complex

    Science.gov (United States)

    Postila, Pekka A.; Kaszuba, Karol; Kuleta, Patryk; Vattulainen, Ilpo; Sarewicz, Marcin; Osyczka, Artur; Róg, Tomasz

    2016-09-01

    The cytochrome (cyt) bc1 complex is an integral component of the respiratory electron transfer chain sustaining the energy needs of organisms ranging from humans to bacteria. Due to its ubiquitous role in the energy metabolism, both the oxidation and reduction of the enzyme’s substrate co-enzyme Q has been studied vigorously. Here, this vast amount of data is reassessed after probing the substrate reduction steps at the Qi-site of the cyt bc1 complex of Rhodobacter capsulatus using atomistic molecular dynamics simulations. The simulations suggest that the Lys251 side chain could rotate into the Qi-site to facilitate binding of half-protonated semiquinone - a reaction intermediate that is potentially formed during substrate reduction. At this bent pose, the Lys251 forms a salt bridge with the Asp252, thus making direct proton transfer possible. In the neutral state, the lysine side chain stays close to the conserved binding location of cardiolipin (CL). This back-and-forth motion between the CL and Asp252 indicates that Lys251 functions as a proton shuttle controlled by pH-dependent negative feedback. The CL/K/D switching, which represents a refinement to the previously described CL/K pathway, fine-tunes the proton transfer process. Lastly, the simulation data was used to formulate a mechanism for reducing the substrate at the Qi-site.

  7. Subsoil heterogeneities controlling porewater contaminant mass and microbial diversity at a site with a complex pollution history.

    Science.gov (United States)

    Puigserver, Diana; Carmona, José M; Cortés, Amparo; Viladevall, Manuel; Nieto, José M; Grifoll, Magdalena; Vila, Joaquim; Parker, Beth L

    2013-01-01

    This study seeks to improve our understanding of the conceptual model of pollutant transport and fate in cases of DNAPL contamination at sites with a complex contamination history. The study was carried out in an unconfined aquifer of alluvial fans in the Tarragona Petrochemical Complex (Spain). Two boreholes were drilled and continuous cores were recovered in order to carry out a detailed core description at centimeter scale and a comprehensive sampling of borehole cores. The biogeochemical heterogeneity at these sites is controlled by the conjunction of lithological, hydrochemical and microbiological heterogeneities. Biodegradation processes of contaminant compounds take place not only at the level of the dissolved fraction in the aquifer but also at the level of the fraction retained in the fine, less conductive materials as shown by the biodegradation haloes of parent and metabolite compounds. Sampling the low-conductivity levels also allowed us to identify compounds, e.g. BTEX, that are the remaining traces of the passage of old contaminant plumes whose sources no longer exist. This enabled us to describe past biogeochemical processes and to partially account for the processes occurring today. Transition zones, characterized by numerous textural changes, constitute ecotones whose biostimulation could be effective in promoting the acceleration of the remediation of the multiple pollution at these sites. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Comparison of the environmental effects on variation in yearly litter decay and soil respiration rates over four years in forested and harvested sites across Canada.

    Science.gov (United States)

    Trofymow, J. A.; Thompson, E.; Cameron, A.; Pare', D.; Lavigne, M.; Amiro, B.; Smyth, C.; Black, A.; Barr, A.; Margolis, H.

    2008-12-01

    Soil respiration includes CO2 respired by plant roots and by soil biota decomposing plant detritus. Detrital C stocks and fluxes are being studied at 16 sites at 7 stations of the Fluxnet Canada Research Network, including paired mature and clearcut forest sites at 5 upland stations (BC, SK, ON, QC, NB). All sites were instrumented for in situ measurements of soil moisture and temperature and many sites also included coincident measurements of soil respiration by chambers. Cumulative litter decay was measured using surface placed litterbags with one of four standard material types (aspen leaves -AL, black spruce needles BS, Douglas fir needles DF and birch wood sticks BW). Six replicate plots were located at each site, each plot contained sufficient numbers of surface litterbags of each material type to allow for four annual collections (2004 - 2007). As well unconfined birch chopsticks were placed at three depths down the soil profile (surface, 5cm, 15cm) and replaced annually to examine interannual variability of decay. After four years cumulative decay, litter rank by %mass remaining had AL

  9. Visualization of PML nuclear import complexes reveals FG-repeat nucleoporins at cargo retrieval sites.

    Science.gov (United States)

    Lång, Anna; Eriksson, Jens; Schink, Kay Oliver; Lång, Emma; Blicher, Pernille; Połeć, Anna; Brech, Andreas; Dalhus, Bjørn; Bøe, Stig Ove

    2017-07-04

    Selective nuclear import in eukaryotic cells involves sequential interactions between nuclear import receptors and phenylalanine-glycine (FG)-repeat nucleoporins. Traditionally, binding of cargoes to import receptors is perceived as a nuclear pore complex independent event, while interactions between import complexes and nucleoporins are thought to take place at the nuclear pores. However, studies have shown that nucleoporins are mobile and not static within the nuclear pores, suggesting that they may become engaged in nuclear import before nuclear pore entry. Here we have studied post-mitotic nuclear import of the tumor suppressor protein PML. Since this protein forms nuclear compartments called PML bodies that persist during mitosis, the assembly of putative PML import complexes can be visualized on the surface of these protein aggregates as the cell progress from an import inactive state in mitosis to an import active state in G1. We show that these post-mitotic cytoplasmic PML bodies incorporate a multitude of peripheral nucleoporins, but not scaffold or nuclear basket nucleoporins, in a manner that depends on FG-repeats, the KPNB1 import receptor, and the PML nuclear localization signal. The study suggests that nucleoporins have the ability to target certain nuclear cargo proteins in a nuclear pore-uncoupled state, before nuclear pore entry.

  10. Modelagem numérica em mapa temático: sítios florestais Numerical modelling in thematical map: forestal sites

    Directory of Open Access Journals (Sweden)

    Cláudia Weber Corseuil

    1998-12-01

    Full Text Available O presente trabalho tem por objetivo a utilização de programas de geoprocessamento e de tratamento de imagens, considerados de domínio público e de fácil operacionalidade, para modelagem numérica de um mapa temático. Esta modelagem é feita a partir da alimentação de um banco de dados digitais, para fins de planejamento e cadastro florestal. Mais especificamente, criou-se uma metodologia que utiliza a modelagem numérica para a visualização tridimensional de um plano de informação de sítios florestais georeferenciados, que permite o cruzamento (sobreposição com outros planos de informações, também georeferenciados, de interesse na área florestal. Foram utilizados os seguintes materiais: mapa de sítios naturais da Floresta Nacional de Passo Fundo, microcomputador, impressora, scanner de mesa, os softwares Idrisi 4.1 e Aldus PhotoStyler 2.0. A metodologia empregada baseou-se na digitalização, por varredura ótica, do mapa de sítios naturais existentes, sua edição de cores e georeferenciamento, para posterior modelagem numérica e visualização tridimensional dos diferentes sítios representados no mapa planimétrico da Floresta Nacional de Passo Fundo. Como resultado, obteve-se arquivos, que possibilitaram a identificação, através das diferentes alturas, dos sítios onde podem ser implantadas espécies mais adequadas às suas características naturais, demonstrando a viabilidade da aplicação da presente metodologia no planejamento florestal.The objective of this work was to utilize programs of geoprocessing and treatment of images, considerated to be well-knowm and easily operated, for numerical modelling of a thematical map. This modelling is carried out from feeding a digital base bank, for forest planning and cadaster. More specifically, a methodology that uses the numerical modelling for tridimensional visualization of a layer of geoindicated forest sites has been designed to permit the crossing (superposition

  11. Conifer seedling recruitment across a gradient from forest to alpine tundra: effects of species, provenance, and site

    Science.gov (United States)

    Castanha, C.; Torn, M.S.; Germino, M.J.; Weibel, Bettina; Kueppers, L.M.

    2013-01-01

    Background: Seedling germination and survival is a critical control on forest ecosystem boundaries, such as at the alpine–treeline ecotone. In addition, while it is known that species respond individualistically to the same suite of environmental drivers, the potential additional effect of local adaptation on seedling success has not been evaluated. Aims: To determine whether local adaptation may influence the position and movement of forest ecosystem boundaries, we quantified conifer seedling recruitment in common gardens across a subalpine forest to alpine tundra gradient at Niwot Ridge, Colorado, USA. Methods: We studied Pinus flexilis and Picea engelmannii grown from seed collected locally at High (3400 m a.s.l.) and Low (3060 m a.s.l.) elevations. We monitored emergence and survival of seeds sown directly into plots and survival of seedlings germinated indoors and transplanted after snowmelt. Results: Emergence and survival through the first growing season was greater for P. flexilis than P. engelmannii and for Low compared with High provenances. Yet survival through the second growing season was similar for both species and provenances. Seedling emergence and survival tended to be greatest in the subalpine forest and lowest in the alpine tundra. Survival was greater for transplants than for field-germinated seedlings. Conclusions: These results suggest that survival through the first few weeks is critical to the establishment of natural germinants. In addition, even small distances between seed sources can have a significant effect on early demographic performance – a factor that has rarely been considered in previous studies of tree recruitment and species range shifts.

  12. Elevated CO2 increases tree-level intrinsic water use efficiency: insights from carbon and oxygen isotope analyses in tree rings across three forest FACE sites

    Energy Technology Data Exchange (ETDEWEB)

    Battipaglia, Giovanna [Second University of Naples; Saurer, Matthias [Paul Scherrer Institut, Villigen, Switzerland; Cherubini, Paulo [WSL Swiss Federal Institute for Forest, Snow and Landscape Research; Califapietra, Carlo [University of Tuscia; McCarthy, Heather R [Duke University; Norby, Richard J [ORNL; Cotrufo, M. Francesca [Colorado State University, Fort Collins

    2013-01-01

    Elevated CO2 increases intrinsic water use efficiency (WUEi) of forests, but the magnitude of this effect and its interaction with climate is still poorly understood. We combined tree ring analysis with isotope measurements at three Free Air CO2 Enrichment (FACE, POP-EUROFACE, in Italy; Duke FACE in North Carolina and ORNL in Tennessee, USA) sites, to cover the entire life of the trees. We used 13C to assess carbon isotope discrimination ( 13C ci/ca) and changes in WUEi, while direct CO2 effects on stomatal conductance were explored using 18O as a proxy. Across all the sites, elevated CO2 increased 13C-derived WUEi on average by 73% for Liquidambar styraciflua, 77% for Pinus taeda and 75% for Populus sp., but through different ecophysiological mechanisms. Our findings provide a robust means of predicting WUEi responses from a variety of tree species exposed to variable environmental conditions over time, and species-specific relationships that can help modeling elevated CO2 and climate impacts on forest productivity, carbon and water balances.

  13. Complex atmospheric-lithospheric observations of acoustic emission at «Karymshina» site in Kamchatka

    Directory of Open Access Journals (Sweden)

    Larionov Igor

    2017-01-01

    Full Text Available The results of complex observations of acoustic emission in the near surface rocks and in the atmosphere by the ground surface are described. The instrumentations for the observations are a laser strainmeter-interferometer and a microbarometer installed close to each other. It was shown that during the increase of deformation rate in the near surface rocks, increase of acoustic emission intensity in the atmosphere by the ground surface is registered. The effect of meteorological factors on the observation results is evaluated.

  14. Improving Independent Student Navigation of Complex Educational Web Sites: An Analysis of Two Navigation Design Changes in LibGuides

    Directory of Open Access Journals (Sweden)

    Kate A Pittsley

    2012-09-01

    Full Text Available Can the navigation of complex research web sites be improved so that users more often find their way without intermediation or instruction?  Librarians at Eastern Michigan University discovered that students were not recognizing navigational elements on web based research guides and tested possible solutions. In this study, two types of navigation improvements were applied to separate sets of online guides. Both sets of experimental guides showed an increase in use of navigation to secondary pages of the guides.

  15. Complex Comparison of Bavarian and Bohemian Forest National Parks from Geographical Perspective: Is there More Similarity or Difference?

    Directory of Open Access Journals (Sweden)

    Janík Tomáš

    2017-01-01

    Full Text Available This article focuses on comparison of the landscape of two National Parks (Bavarian and Bohemian Forest, which together create the largest area of wilderness in Central Europe. The article shows how different they are in social-economic and physical-geographical perspective. Social and economic conditions were introduced from perspective of path dependency and recent situation and its perception. Furthermore, we integrated social-economic and environmental perspective in the ecosystem services concept. Despite the lesser number tourists arriving to the Bavarian part of the area, perception is better than among mayors of municipalities on the Czech side. Different history, management and top-down and bottom-up approaches usage can explain these differences. The typologies of environmental conditions help us to distinguish differences between both National Parks. In the Bavarian Forest we can find more equal share of forests (coniferous, broad-leaved, mixed and surprisingly, thanks to large unmanaged part bigger relative share of regenerating forest landscapes than in the Bohemian Forest. Physical-geographical typology distinguishes five classes. Relative distribution of the classes is similar, but we can determine area of high plateau mainly on Czech side and on the other hand class of steeper terrain is located mainly in Bavarian Forest. Ecosystem services was presented by integrating landscape capacity analysis showing small differences between both National Parks in this case and no relation between land cover and attractiveness for tourism.

  16. Mapping of the binding site on pseudoazurin in the transient 152 kDa complex with nitrite reductase.

    Science.gov (United States)

    Impagliazzo, Antonietta; Ubbink, Marcellus

    2004-05-12

    Nitrite reductase (NiR) catalyzes the reduction of nitrite to nitrite oxide as a part of the denitrification process. In Alcaligenes faecalis S-6, the copper protein pseudoazurin acts as electron donor to NiR. The binding surface of pseudoazurin involved in the formation of the 152 kDa complex with NiR has been determined by NMR using cross saturation from NiR to perdeuterated pseudoazurin. Due to the transient nature of the complex, saturation effects can be observed on the resonances of the unbound protein. The binding site comprises the hydrophobic area surrounding the exposed copper ligand His81, suggesting that this residue is important for efficient electron transfer.

  17. 3D surveying and modelling of complex architectural sites and heritage objects

    Directory of Open Access Journals (Sweden)

    Fabio Remondino

    2011-12-01

    Full Text Available The actual techniques and methodologies for 3D surveying and modeling allow to achieve very satisfactory and impressive results in the field of documentation, conservation and representation of architectural sites and heritage objects. A great variety of active or passive sensors are available for data acquisition. These data are then processed in order to derive metric 3D information and share them using online databases or GIS tools. But despite the large amount of data, the processing methodologies are still relying very often on manual restitution as automatic method are still not enough reliable for the detailed and precise 3D reconstruction of architectural scenarios and drawings. The articles reports the actual 3D surveying methodologies and data processing techniques with a critical description of open problems and research issues.

  18. Tightly bound DNA-protein complexes representing stable attachment sites of large DNA loops to components of the matrix.

    Science.gov (United States)

    Patriotis, C; Djondjurov, L

    1989-09-01

    This study describes tightly bound DNA-protein complexes in DNA of matrices isolated from Friend erythroleukemia cells. When after radio-iodination of the associated proteins, such DNA is electrophoresed on agarose and the gel is subsequently subjected to autoradiography, the protein components of three or four complexes are visualized. Their two-dimensional electrophoretic analysis revealed that each possesses a simple but specific polypeptide composition, including a set of five non-histone proteins, characteristic for the matrix, and the core histones H3 and H4. Since the polypeptides dissociate from DNA by treatment with SDS, it is suggested that the linkage is not covalent. Reassociation and hybridization analysis of the DNA of the complexes indicated that it is enriched in highly repetitive, satellite sequences. The latter were found to be, to a great extent, similar to sequences localized at the base of large, dehistonized DNA loops obtained by high-salt extraction of isolated nuclei. Further experiments emphasized the complete conservation of this type of attachment throughout erythroid differentiation of Friend cells. It is proposed that the complexes represent attachment sites of basic, 30-100-kbp loop units of DNA.

  19. Utilizing the Niwot Rige longterm ecological research site surface data to verify remotely sensed snow parameters over complex terrain

    Science.gov (United States)

    McIntyre, H. M.

    2009-12-01

    The variability and extent of seasonal snow cover are important parameters in climate and hydrologic systems due to their effects on energy and moisture budgets. During its maximum extent, seasonal snow can cover more than 50% (50 million km2) of the Northern Hemisphere's land surface. Snow covered area (SCA) represents the largest single component of the cryosphere that fluctuates seasonally. Satellite remote sensing allows us the ability to monitor snow parameters such as snow covered area (SCA) but lacks the resolution required for adequate coverage in mountainous terrain in three main areas: subalpine forests, patchy snow coverage, and steep terrain (slope>30o). This proposed research would address these issues by comparing surface data collected in the Niwot Ridge LTER (Long-term Ecological Research Site) during the snow season of 2009-2010 to that of satellite remote sensing data on the subpixel scale. Statistical sampling techniques based on the Cold-land Processes Field Experiment (CLPX, 2001-2004) will be utilized to determine the percentage of snow covered area on the ground and then compare these values with those of the MODSCAG (MODIS Snow Covered Area and Grain Size) model. This comparison will provide valuable testing of the MODSCAG model and future algorithm development. The results of this study will also provide more accurate remotely sensed snow covered area for input into land-surface, regional scale, and global climate models.

  20. Site-selective oxidation, amination and epimerization reactions of complex polyols enabled by transfer hydrogenation

    Science.gov (United States)

    Hill, Christopher K.; Hartwig, John F.

    2017-12-01

    Polyoxygenated hydrocarbons that bear one or more hydroxyl groups comprise a large set of natural and synthetic compounds, often with potent biological activity. In synthetic chemistry, alcohols are important precursors to carbonyl groups, which then can be converted into a wide range of oxygen- or nitrogen-based functionality. Therefore, the selective conversion of a single hydroxyl group in natural products into a ketone would enable the selective introduction of unnatural functionality. However, the methods known to convert a simple alcohol, or even an alcohol in a molecule that contains multiple protected functional groups, are not suitable for selective reactions of complex polyol structures. We present a new ruthenium catalyst with a unique efficacy for the selective oxidation of a single hydroxyl group among many in unprotected polyol natural products. This oxidation enables the introduction of nitrogen-based functional groups into such structures that lack nitrogen atoms and enables a selective alcohol epimerization by stepwise or reversible oxidation and reduction.

  1. An Evaluation of Site-specific and Generalized Spatial Models of Aboveground Forest Biomass Based on Landsat Time-series and LiDAR Strip Samples in the Eastern U.S.A.

    Science.gov (United States)

    Deo, R. K.; Domke, G. M.; Russell, M.; Andersen, H. E.; Cohen, W. B.

    2016-12-01

    Aboveground forest biomass (AGB) contributes a large part of the terrestrial carbon and varies with forest types. While forest disturbance and land use changes significantly influence greenhouse gas (GHG) emissions, international conventions on climate change mitigation have identified forest conservation and management as an efficient mechanism for enhancing carbon storage in live plant biomass to offset the emissions. Regional or national scale assessment of AGB on forest lands facilitates strategic plans such as the national GHG inventory per the requirement of the United Nations Framework Convention on Climate Change (UNFCCC). Large area inventory of AGB can be efficiently carried out by using remotely sensed data and a generalized statistical model in contrast to using only field measurements and site-specific models. In this study, we have integrated specialized forest inventory plot data with spatial predictors derived from time-series Landsat imagery and LiDAR strip samples in four sites across the eastern U.S.A.- Minnesota (MN), Maine (ME), Pennsylvania-New Jersey (PANJ) and South Carolina (SC) - to formulate statistical models. Pixel-level polynomial curve fit was applied to the time-series Landsat variables to obtain projected metrics in the target year 2014. Two forms of models based on ordinary least-squares regression (OLR) and the random forest (RF) algorithm were developed for each site and with the pooled (generalized) dataset. The site-specific models were tested with the national forest inventory (NFI) data as well as specialized plot data of the other sites while the generalized models were tested with the NFI data only. We observed similar level of accuracies with the OLR and RF models at the same site. Although the RF models yielded larger values for the amount of explained variance (i.e., pseudo R2) in the site-specific models, the generalized model was also promising. The amount of variance explained with the site-site specific models were

  2. Earth modeling and estimation of the local seismic ground motion due to site geology in complex volcanoclastic areas

    Directory of Open Access Journals (Sweden)

    V. Di Fiore

    2002-06-01

    Full Text Available Volcanic areas often show complex behaviour as far as seismic waves propagation and seismic motion at surface are concerned. In fact, the finite lateral extent of surface layers such as lava flows, blocks, differential welding and/or zeolitization within pyroclastic deposits, introduces in the propagation of seismic waves effects such as the generation of surface waves at the edge, resonance in lateral direction, diffractions and scattering of energy, which tend to modify the amplitude as well as the duration of the ground motion. The irregular topographic surface, typical of volcanic areas, also strongly influences the seismic site response. Despite this heterogeneity, it is unfortunately a common geophysical and engineering practice to evaluate even in volcanic environments the subsurface velocity field with monodimensional investigation method (i.e. geognostic soundings, refraction survey, down-hole, etc. prior to the seismic site response computation which in a such cases is obviously also made with 1D algorithms. This approach often leads to highly inaccurate results. In this paper we use a different approach, i.e. a fully 2D P-wave Çturning rayÈ tomographic survey followed by 2D seismic site response modeling. We report here the results of this approach in three sites located at short distance from Mt. Vesuvius and Campi Flegrei and characterized by overburdens constituted by volcanoclastic deposits with large lateral and vertical variations of their elastic properties. Comparison between 1D and 2D Dynamic Amplification Factor shows in all reported cases entirely different results, both in terms of peak period and spectral contents, as expected from the clear bidimensionality of the geological section. Therefore, these studies suggest evaluating carefully the subsoil geological structures in areas characterized by possible large lateral and vertical variations of the elastic properties in order to reach correct seismic site response

  3. Surface complexation modeling of U(VI) adsorption by aquifer sediments from a former mill tailings site at Rifle, Colorado

    Science.gov (United States)

    Hyun, S.P.; Fox, P.M.; Davis, J.A.; Campbell, K.M.; Hayes, K.F.; Long, P.E.

    2009-01-01

    A study of U(VI) adsorption by aquifer sediment samples from a former uranium mill tailings site at Rifle, Colorado, was conducted under oxic conditions as a function of pH, U(VI), Ca, and dissolved carbonate concentration. Batch adsorption experiments were performed using <2mm size sediment fractions, a sand-sized fraction, and artificial groundwater solutions prepared to simulate the field groundwater composition. To encompass the geochemical conditions of the alluvial aquifer at the site, the experimental conditions ranged from 6.8 ?? 10-8 to 10-5 M in [U(VI)]tot, 7.2 to 8.0 in pH, 3.0 ?? 10-3 to 6.0 ?? 10 -3 M in [Ca2+], and 0.05 to 2.6% in partial pressure of carbon dioxide. Surface area normalized U(VI) adsorption Kd values for the sand and <2 mm sediment fraction were similar, suggesting a similar reactive surface coating on both fractions. A two-site two-reaction, nonelectrostatic generalized composite surface complexation model was developed and successfully simulated the U(VI) adsorption data. The model successfully predicted U(VI) adsorption observed from a multilevel sampling well installed at the site. A comparison of the model with the one developed previously for a uranium mill tailings site at Naturita, Colorado, indicated that possible calcite nonequilibrium of dissolved calcium concentration should be evaluated. The modeling results also illustrate the importance of the range of data used in deriving the best fit model parameters. ?? 2009 American Chemical Society.

  4. Evaluating the Community Land Model (CLM4.5) at a coniferous forest site in northwestern United States using flux and carbon-isotope measurements

    Science.gov (United States)

    Duarte, Henrique F.; Raczka, Brett M.; Ricciuto, Daniel M.; Lin, John C.; Koven, Charles D.; Thornton, Peter E.; Bowling, David R.; Lai, Chun-Ta; Bible, Kenneth J.; Ehleringer, James R.

    2017-09-01

    Droughts in the western United States are expected to intensify with climate change. Thus, an adequate representation of ecosystem response to water stress in land models is critical for predicting carbon dynamics. The goal of this study was to evaluate the performance of the Community Land Model (CLM) version 4.5 against observations at an old-growth coniferous forest site in the Pacific Northwest region of the United States (Wind River AmeriFlux site), characterized by a Mediterranean climate that subjects trees to water stress each summer. CLM was driven by site-observed meteorology and calibrated primarily using parameter values observed at the site or at similar stands in the region. Key model adjustments included parameters controlling specific leaf area and stomatal conductance. Default values of these parameters led to significant underestimation of gross primary production, overestimation of evapotranspiration, and consequently overestimation of photosynthetic 13C discrimination, reflected in reduced 13C : 12C ratios of carbon fluxes and pools. Adjustments in soil hydraulic parameters within CLM were also critical, preventing significant underestimation of soil water content and unrealistic soil moisture stress during summer. After calibration, CLM was able to simulate energy and carbon fluxes, leaf area index, biomass stocks, and carbon isotope ratios of carbon fluxes and pools in reasonable agreement with site observations. Overall, the calibrated CLM was able to simulate the observed response of canopy conductance to atmospheric vapor pressure deficit (VPD) and soil water content, reasonably capturing the impact of water stress on ecosystem functioning. Both simulations and observations indicate that stomatal response from water stress at Wind River was primarily driven by VPD and not soil moisture. The calibration of the Ball-Berry stomatal conductance slope (mbb) at Wind River aligned with findings from recent CLM experiments at sites characterized by

  5. Isotopic and nutritional evidence for species- and site-specific responses to N deposition and elevated CO2 in temperate forests

    Science.gov (United States)

    Silva, Lucas C. R.; Gómez-Guerrero, Armando; Doane, Timothy A.; Horwath, William R.

    2015-06-01

    In this study we show that the effect of rising atmospheric CO2 levels on forest productivity is influenced by changes in nutrient availability caused by nitrogen (N) deposition. We used a dual-isotope approach (δ15N and δ13C), combined with dendrochronological and nutritional analyses, to evaluate the response of two dominant tree species in natural forest ecosystems near Mexico City (Pinus hartwegii—pine; Abies religiosa—fir). Our analysis focuses on changes that occurred over the past 50 years at two sites, one under high and one under low N deposition rates. Analyses of carbon isotope composition indicate increasing water-use efficiency in response to rising CO2 levels for both species and sites but this effect did not lead to improved tree growth. The magnitude and direction of shifts in 13C discrimination indicate a process of acclimation that varied with the rate of N deposition and species traits. Since the 1960s, strong negative responses to N deposition have been observed in fir trees, which showed altered foliar nutrition and growth decline, while the negative impacts of N deposition on pine trees remained undetectable until the 1990s. In recent years, both species have shown significant growth decline under high N deposition despite increasing atmospheric CO2. Multivariate analysis of leaf nutrients indicates that growth decline was prompted by depleted soil macronutrient (P, K, and Ca) and micronutrient (Cu, Fe, Zn, and Mn) availability. At both sites, fir trees were a better indicator of N deposition due to differences in canopy rainfall interception.

  6. Environmental analysis of a formerly utilized MED/AEC site: Site A and plot M, Palos Forest Preserve, Palos Park, Illinois

    Energy Technology Data Exchange (ETDEWEB)

    1979-09-01

    This environmental analysis report describes the existing site environment and evaluates the environmental impacts of 8 options for remedial action, including allowing buried waste to remain undisturbed. Conformity or conflict with governmental statutes, regulations and standards was determined, especially with regard to compliance with contamination criteria and guidelines. The program of measurements, documentation, and control to demonstrate compliance with these criteria and guidelines was identified.

  7. A proton-coupled dynamic conformational switch in the HIV-1 dimerization initiation site kissing complex.

    Science.gov (United States)

    Mihailescu, Mihaela-Rita; Marino, John P

    2004-02-03

    In HIV type 1 (HIV-1), the dimerization initiation site (DIS) is the sequence primarily responsible for initiating the noncovalent linkage of two homologous strands of genomic RNA during viral assembly. The DIS loop contains an autocomplementary hexanucleotide sequence and forms a symmetric homodimer through a loop-loop kissing interaction. In a structural rearrangement catalyzed by the HIV-1 nucleocapsid protein (NCp7) and suggested to be associated with maturation of the budded viral particle, the DIS converts from a metastable kissing dimer to an extended duplex. Here, we demonstrate that the DIS kissing dimer displays localized conformational dynamics that result from the specific protonation of the N1 base nitrogen of the DIS loop residue A272 at near-physiological pH. The rate of NCp7-catalyzed maturation of the DIS kissing dimer is also shown to directly correlate with the observed proton-coupled conformational dynamics, where NCp7 is found to convert the dynamic A272 protonated state with a faster rate. Taken together, these results reveal a previously undescribed role for base protonation in modulating local RNA structure and demonstrate a mechanism for promoting the chaperone-mediated structural rearrangement of a kinetically trapped RNA conformational state.

  8. Mistaken Point Ecological Reserve: Protecting the World's Oldest Complex Macrofossils at a Newly Inscribed UNESCO World Heritage Site

    Science.gov (United States)

    Matthews, Jack

    2017-04-01

    The late Ediacaran rocks of the Mistaken Point Ecological Reserve, Newfoundland, record the oldest known assemblage of large, complex fossils anywhere. These fossils represent the transition in the history of life on earth to large, architecturally complex organisms, following nearly three billion years of a microbially-dominated world. In July 2016, the Reserve was inscribed on World Heritage List. Inscription has led to increased geotourism demands on the locality, a consequence welcomed by the local community who wish to develop the economy. This is potentially at odds with the interests of Government and Researchers whose inclination is often to prohibit all activity that may adversely impact a site. This presentation will outline several approaches being used to quantitatively measure potential historic and current damage to the Mistaken Point Ecological Reserve from geotourism activity, as well as natural events. Technologies such as LiDAR scanning, photogrammetry, and time lapse cameras are compared and contrasted for their suitability to monitor the integrity of fossil sites. Footwear erosion of fossil surfaces remains a concern of policy makers at the Reserve; experimental work to test the benefits of various footwear erosion reduction protocols is discussed. The legislative and management framework for the Reserve is reviewed, and the importance of building academic-community-government relationships examined. The benefits of geoconservation are shared by all in society - as such the importance of presenting geoconservation research outcomes in ways specifically tailored to local communities and policy makes is highlighted.

  9. A stable isotope approach for source apportionment of chlorinated ethene plumes at a complex multi-contamination events urban site.

    Science.gov (United States)

    Nijenhuis, Ivonne; Schmidt, Marie; Pellegatti, Eleonora; Paramatti, Enrico; Richnow, Hans Hermann; Gargini, Alessandro

    2013-10-01

    The stable carbon isotope composition of chlorinated aliphatic compounds such as chlorinated methanes, ethanes and ethenes was examined as an intrinsic fingerprint for apportionment of sources. A complex field site located in Ferrara (Italy), with more than 50years history of use of chlorinated aliphatic compounds, was investigated in order to assess contamination sources. Several contamination plumes were found in a complex alluvial sandy multi-aquifer system close to the river Po; sources are represented by uncontained former industrial and municipal dump sites as well as by spills at industrial areas. The carbon stable isotope signature allowed distinguishing 2 major sources of contaminants. One source of chlorinated aliphatic contaminants was strongly depleted in ¹³C (-40‰ which is commonly observed in recent production of chlorinated solvents. The degradation processes in the plumes could be traced interpreting the isotope enrichment and depletion of parent and daughter compounds, respectively. We demonstrate that, under specific production conditions, namely when highly chlorinated ethenes are produced as by-product during chloromethanes production, ¹³C depleted fingerprinting of contaminants can be obtained and this can be used to track sources and address the responsible party of the pollution in urban areas. © 2013 Elsevier B.V. All rights reserved.

  10. The low molecular weight protein PsaI stabilizes the light-harvesting complex II docking site of photosystem I

    DEFF Research Database (Denmark)

    Plöchinger, Magdalena; Torabi, Salar; Rantala, Marjaana

    2016-01-01

    PsaI represents one of three low molecular weight peptides of PSI. Targeted inactivation of the plastid PsaI gene in Nicotiana tabacum has no measurable effect on photosynthetic electron transport around PSI or on accumulation of proteins involved in photosynthesis. Instead, the lack of PsaI dest...... of mutant plants into state 2 in darkness represents a compensatory and/or protective metabolic mechanism. This involves an increased reduction and/or reduced oxidation of the PQ pool, presumably to sustain a balanced excitation of both photosystems upon the onset of light.......PsaI represents one of three low molecular weight peptides of PSI. Targeted inactivation of the plastid PsaI gene in Nicotiana tabacum has no measurable effect on photosynthetic electron transport around PSI or on accumulation of proteins involved in photosynthesis. Instead, the lack of Psa......I destabilizes the association of PsaL and PsaH to PSI, both forming the light-harvesting complex (LHC)II docking site of PSI. These alterations at the LHCII binding site surprisingly did not prevent state transition but led to an increased incidence of PSI-LHCII complexes, coinciding with an elevated...

  11. Systematic revision of the Parvoscincus decipiens (Boulenger, 1894) complex of Philippine forest skinks (Squamata: Scincidae: Lygosominae) with descriptions of seven new species.

    Science.gov (United States)

    Linkem, Charles W; Brown, Rafe M

    2013-01-01

    Analysis of external morphological characters, color pattern, and DNA sequence data, plus consideration of biogeographical patterns, leads us to the hypothesis that the Parvoscincus decipiens complex of Philippine forest skinks consists of a minimum of eight highly divergent, phenotypically distinct, cohesive evolutionary lineages. We rectify this taxonomic underestimation of species diversity with formal descriptions of seven new species (P. abstrusus sp. nov., P. agtorum sp. nov., P. arvindiesmosi sp. nov., P aurorus sp. nov., P banahaoensis sp. nov., P. jimmymcguirei sp. nov., and P. palaliensis sp. nov.) and highlight geographical sampling deficiencies, which, if addressed with additional fieldwork, should lead to additional new species discoveries. Due to the difficulty of identifying non-overlapping differences in scalation on similarly sized, small-bodied skinks, species level diversity in diminutive Philippine forest skinks is undoubtedly substantially underestimated.

  12. A new species of karst forest-adapted Bent-toed Gecko (genus Cyrtodactylus Gray, 1827) belonging to the C. sworderi complex from a threatened karst forest in Perak, Peninsular Malaysia.

    Science.gov (United States)

    Grismer, L Lee; Belabut, Daicus M; Quah, Evan S H; Onn, Chan Kin; Wood, Perry L

    2014-01-24

    A new species of Bent-toed Gecko Cyrtodactylus guakanthanensis sp. nov. of the C. sworderi complex is described from a limestone forest in Perak, Peninsular Malaysia whose karst formations at the type locality are within an active quarry. Cyrtodactylus guakanthanensis sp. nov. can be distinguished from all other Sundaland species by having the following suite of character states: adult SVL 77.7-82.2 mm; moderately sized, conical, weakly keeled, body tubercles; tubercles present on occiput, nape, and limbs, and extend posteriorly beyond base of tail; 37-44 ventral scales; no transversely enlarged, median, subcaudal scales; proximal subdigital lamellae transversely expanded; 19-21 subdigital lamellae on fourth toe; abrupt transition between posterior and ventral femoral scales; enlarged femoral scales; no femoral or precloacal pores; precloacal groove absent; wide, dark postorbital stripes from each eye extending posteriorly to the anterior margin of the shoulder region thence forming a transverse band across the anterior margin of the shoulder region; and body bearing five (rarely four) wide, bold, dark bands. Destruction of the karst microhabitat and surrounding limestone forest will extirpate this new species from the type locality and perhaps drive it to complete extinction given that it appears to be restricted to the particular microhabitat structure of the type locality and is not widely distributed throughout the karst formations. As with plants and invertebrates, limestone forests are proving to be significant areas of high herpetological endemism and should be afforded special conservation status rather than turned into cement.

  13. Introducing a dark reaction to photochemistry: photocatalytic hydrogen from [FeFe] hydrogenase active site model complexes.

    Science.gov (United States)

    Lomoth, Reiner; Ott, Sascha

    2009-12-07

    The light-driven splitting of water into its constituting elements gives access to a valuable fuel from an abundant substrate, using sunlight as the only energy source. Synthetic diiron complexes as functional models of the [FeFe] hydrogenase H2ase enzyme active site have moved into the centre of focus as potentially viable catalysts for the reductive side of this process, i.e. the reduction of protons to molecular hydrogen. The active site of the enzyme, as well as its mimics in an artificial system, are required to accumulate two electrons from single electron transfer events and to combine them with two protons to form hydrogen. Whereas in biology this reaction is not coupled to photosynthesis and thus proceeds in the dark, additional aspects need to be considered when designing a functional artificial system for the light-driven reduction of protons. Suitable photosensitizers have to be chosen that not only provide sufficient driving force for the reduction of the synthetic diiron catalyst, but also allow for selective excitation to minimize photodegradation. Electron transfer efficiencies have to be optimized for all steps and the sequential nature of the catalyst reduction requires a sufficient stability of potentially labile intermediates of the catalytic cycle. In this perspective, systems for the light-driven conversion of protons to molecular hydrogen are discussed where the catalyst is based on model complexes of the [FeFe] H2ase active site. Covalently linked dyads, supramolecular assemblies and multi-component systems will be examined with an emphasis on mechanistic electron transfer schemes, the properties of the individual components, their scope and their potential limitations.

  14. Directional R-Loop Formation by the CRISPR-Cas Surveillance Complex Cascade Provides Efficient Off-Target Site Rejection

    Directory of Open Access Journals (Sweden)

    Marius Rutkauskas

    2015-03-01

    Full Text Available CRISPR-Cas systems provide bacteria and archaea with adaptive immunity against foreign nucleic acids. In type I CRISPR-Cas systems, invading DNA is detected by a large ribonucleoprotein surveillance complex called Cascade. The crRNA component of Cascade is used to recognize target sites in foreign DNA (protospacers by formation of an R-loop driven by base-pairing complementarity. Using single-molecule supercoiling experiments with near base-pair resolution, we probe here the mechanism of R-loop formation and detect short-lived R-loop intermediates on off-target sites bearing single mismatches. We show that R-loops propagate directionally starting from the protospacer-adjacent motif (PAM. Upon reaching a mismatch, R-loop propagation stalls and collapses in a length-dependent manner. This unambiguously demonstrates that directional zipping of the R-loop accomplishes efficient target recognition by rapidly rejecting binding to off-target sites with PAM-proximal mutations. R-loops that reach the protospacer end become locked to license DNA degradation by the auxiliary Cas3 nuclease/helicase without further target verification.

  15. Structure of a Clostridium botulinum C143S thiaminase I/thiamin complex reveals active site architecture .

    Science.gov (United States)

    Sikowitz, Megan D; Shome, Brateen; Zhang, Yang; Begley, Tadhg P; Ealick, Steven E

    2013-11-05

    Thiaminases are responsible for the degradation of thiamin and its metabolites. Two classes of thiaminases have been identified based on their three-dimensional structures and their requirements for a nucleophilic second substrate. Although the reactions of several thiaminases have been characterized, the physiological role of thiamin degradation is not fully understood. We have determined the three-dimensional X-ray structure of an inactive C143S mutant of Clostridium botulinum (Cb) thiaminase I with bound thiamin at 2.2 Å resolution. The C143S/thiamin complex provides atomic level details of the orientation of thiamin upon binding to Cb-thiaminase I and the identity of active site residues involved in substrate binding and catalysis. The specific roles of active site residues were probed by using site directed mutagenesis and kinetic analyses, leading to a detailed mechanism for Cb-thiaminase I. The structure of Cb-thiaminase I is also compared to the functionally similar but structurally distinct thiaminase II.

  16. 3D simulation of boreal forests: structure and dynamics in complex terrain and in a changing climate

    Science.gov (United States)

    Brazhnik, Ksenia; Shugart, Herman H.

    2015-10-01

    To understand how the Siberian boreal forests may respond to near-future climate change, we employed a modeling approach and examined thresholds for significant and irreversible changes in forest structure and composition that are likely to be reached by mid-21st century. We applied the new spatially-explicit gap-dynamics model SIBBORK toward the understanding of how transition zones, namely treelines, which are notoriously undersampled and difficult to model, may change in the near future. We found that a 2 °C change in annual average air temperature significantly altered the structure, composition, and productivity of boreal forests stands both in the northern and the southern treeline ecotones. Treeline migration occurs at smaller temperature changes. Based on the current (1990-2014) observed warming trends, a 2 °C increase in annual average temperature compared to historical climate (1961-1990) is likely to be experienced at the northern treeline by 2040 and at the southern treeline by 2050. With regards to the forest biome, the most significant warming to date has been predicted and observed in Siberia. A 2 °C increase in annual average temperature compared to the second half of the 19th century is smaller than the predictions of even the most conservative RCP2.6 climate change scenario (IPCC 2013), and has previously been assumed to not likely result in dramatic changes to ecosystems or biome shifts. We show that at a +2 °C change, biome shifts from forest to steppe are likely to occur across a large area in southern Siberia. These changes in land cover will inevitably result in changes in the biodiversity, carbon storage, and the ecosystem services provided by the boreal forests of southern Siberia.

  17. Scanning mutagenesis of the amino acid sequences flanking phosphorylation site 1 of the mitochondrial pyruvate dehydrogenase complex

    Directory of Open Access Journals (Sweden)

    Nagib eAhsan

    2012-07-01

    Full Text Available The mitochondrial pyruvate dehydrogenase complex is regulated by reversible seryl-phosphorylation of the E1α subunit by a dedicated, intrinsic kinase. The phospho-complex is reactivated when dephosphorylated by an intrinsic PP2C-type protein phosphatase. Both the position of the phosphorylated Ser-residue and the sequences of the flanking amino acids are highly conserved. We have used the synthetic peptide-based kinase client assay plus recombinant pyruvate dehydrogenase E1α and E1α-kinase to perform scanning mutagenesis of the residues flanking the site of phosphorylation. Consistent with the results from phylogenetic analysis of the flanking sequences, the direct peptide-based kinase assays tolerated very few changes. Even conservative changes such as Leu, Ile, or Val for Met, or Glu for Asp, gave very marked reductions in phosphorylation. Overall the results indicate that regulation of the mitochondrial pyruvate dehydrogenase complex by reversible phosphorylation is an extreme example of multiple, interdependent instances of co-evolution.

  18. Computational study of hydration at the TD damaged site of DNA in complex with repair enzyme T4 endonuclease V

    Energy Technology Data Exchange (ETDEWEB)

    Pinak, Miroslav [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2000-02-01

    An analysis of the distribution of water around DNA surface focusing on the role of the distribution of water molecules in the proper recognition of damaged site by repair enzyme T4 Endonuclease V was performed. The native DNA dodecamer, dodecamer with the thymine dimer (TD) and complex of DNA and part of repair enzyme T4 Endonuclease V were examined throughout the 500 ps of molecular dynamics simulation. During simulation the number of water molecules close to the DNA atoms and the residence time were calculated. There is an increase in number of water molecules lying in the close vicinity to TD if compared with those lying close to two native thymines (TT). Densely populated area with water molecules around TD is one of the factors detected by enzyme during scanning process. The residence time was found higher for molecule of the complex and the six water molecules were found occupying the stabile positions between the TD and catalytic center close to atoms P, C3' and N3. These molecules originate water mediated hydrogen bond network that contribute to the stability of complex required for the onset of repair process. (author)

  19. An unexpected phosphate binding site in Glyceraldehyde 3-Phosphate Dehydrogenase: Crystal structures of apo, holo and ternary complex of Cryptosporidium parvum enzyme

    Directory of Open Access Journals (Sweden)

    Chattopadhyay Debasish

    2009-02-01

    Full Text Available Abstract Background The structure, function and reaction mechanism of glyceraldehyde 3-phosphate dehydrogenase (GAPDH have been extensively studied. Based on these studies, three anion binding sites have been identified, one 'Ps' site (for binding the C-3 phosphate of the substrate and two sites, 'Pi' and 'new Pi', for inorganic phosphate. According to the original flip-flop model, the substrate phosphate group switches from the 'Pi' to the 'Ps' site during the multistep reaction. In light of the discovery of the 'new Pi' site, a modified flip-flop mechanism, in which the C-3 phosphate of the substrate binds to the 'new Pi' site and flips to the 'Ps' site before the hydride transfer, was proposed. An alternative model based on a number of structures of B. stearothermophilus GAPDH ternary complexes (non-covalent and thioacyl intermediate proposes that in the ternary Michaelis complex the C-3 phosphate binds to the 'Ps' site and flips from the 'Ps' to the 'new Pi' site during or after the redox step. Results We determined the crystal structure of Cryptosporidium parvum GAPDH in the apo and holo (enzyme + NAD state and the structure of the ternary enzyme-cofactor-substrate complex using an active site mutant enzyme. The C. parvum GAPDH complex was prepared by pre-incubating the enzyme with substrate and cofactor, thereby allowing free movement of the protein structure and substrate molecules during their initial encounter. Sulfate and phosphate ions were excluded from purification and crystallization steps. The quality of the electron density map at 2Å resolution allowed unambiguous positioning of the substrate. In three subunits of the homotetramer the C-3 phosphate group of the non-covalently bound substrate is in the 'new Pi' site. A concomitant movement of the phosphate binding loop is observed in these three subunits. In the fourth subunit the C-3 phosphate occupies an unexpected site not seen before and the phosphate binding loop remains in

  20. Long-term stewardship of the environmental legacy at restored sites within the Department of Energy nuclear weapons complex.

    Science.gov (United States)

    Wells, James R; Spitz, Henry B

    2003-11-01

    It is readily apparent, as the Department of Energy Office of Environmental Management proceeds in remediating its vast network of contaminated nuclear weapons facilities, that final cleanup at many facilities will not be performed to a level allowing unrestricted use of the facility. Instead, these facilities must rely on engineering, administrative, and institutional controls to ensure the level of cleanup performed at the site remains adequately protective of public health and the environment. In order for these controls to remain effective, however, a plan for long-term stewardship of these sites must be developed that is approved by the U.S. Congress. Although this sounds simple enough for the present, serious questions remain regarding how best to implement a program of stewardship to ensure its effectiveness over time, particularly for sites with residual contamination of radionuclides with half-lives on the order of thousands of years. Individual facilities have attempted to answer these questions at the site-specific level. However, the complexities of the issues require federal support and oversight to ensure the programs implemented at each of the facilities are consistent and effective. The Department of Energy recently submitted a report to Congress outlining the extent of long-term stewardship needs at each of its facilities. As a result, the time is ripe for forward thinking Congressional action to address the relevant issues and ensure the remedy of long-term stewardship successfully carries out its intended purpose and remains protective of public health and the environment. The regulatory elements necessary for the stewardship program to succeed can only be implemented through the plenary powers of the U.S. Congress.

  1. The complexities of measuring access to parks and physical activity sites in New York City: a quantitative and qualitative approach

    Directory of Open Access Journals (Sweden)

    Sohler Nancy L

    2009-06-01

    Full Text Available Abstract Background Proximity to parks and physical activity sites has been linked to an increase in active behaviors, and positive impacts on health outcomes such as lower rates of cardiovascular disease, diabetes, and obesity. Since populations with a low socio-economic status as well as racial and ethnic minorities tend to experience worse health outcomes in the USA, access to parks and physical activity sites may be an environmental justice issue. Geographic Information systems were used to conduct quantitative and qualitative analyses of park accessibility in New York City, which included kernel density estimation, ordinary least squares (global regression, geographically weighted (local regression, and longitudinal case studies, consisting of field work and archival research. Accessibility was measured by both density of park acreage and density of physical activity sites. Independent variables included percent non-Hispanic black, percent Hispanic, percent below poverty, percent of adults without high school diploma, percent with limited English-speaking ability, and population density. Results The ordinary least squares linear regression found weak relationships in both the park acreage density and the physical activity site density models (Ra2 = .11 and .23, respectively; AIC = 7162 and 3529, respectively. Geographically weighted regression, however, suggested spatial non-stationarity in both models, indicating disparities in accessibility that vary over space with respect to magnitude and directionality of the relationships (AIC = 2014 and -1241, respectively. The qualitative analysis supported the findings of the local regression, confirming that although there is a geographically inequitable distribution of park space and physical activity sites, it is not globally predicted by race, ethnicity, or socio-economic status. Conclusion The combination of quantitative and qualitative analyses demonstrated the complexity of the issues around

  2. Complexity

    Indian Academy of Sciences (India)

    Rahul Pandit

    2008-10-31

    Oct 31, 2008 ... ”The more complex a thing is, the more you can talk about it.” - attributed to Giorgio Parisi. ▻ ”C'est magnifique, mais ce n'est pas de la science.” (It is magnificent, but not all of it is science.) - attributed ... Earliest examples: theoretical computer science, algorithmic complexity, etc. ▻ Rapid progress after the ...

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

    Science.gov (United States)

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

    2014-01-01

    Global change is impacting forests worldwide, threatening biodiversity and ecosystem services including climate regulation. Understanding how forests respond is critical to forest conservation and climate protection. This review describes an international network of 59 long-term forest dynamics research sites (CTFS-ForestGEO) useful for characterizing forest responses...

  4. Long-term integrated studies show complex and surprising effects of climate change in northern hardwood forests

    Science.gov (United States)

    Peter M. Groffman; Lindsey Rustad; Pamela H. Templer; John Campbell; Lynn M. Christenson; Nina K. Lany; Anne M. Socci; Matthew A. Vadeboncoeur; Paul Schaberg; Geoffrey F. Wilson; Charles T. Driscoll; Timothy J. Fahey; Melany C. Fisk; Christine L. Goodale; Mark B. Green; Steven P. Hamburg; Chris E. Johnson; Myron J. Mitchell; Jennifer L. Morse; Linda H. Pardo; Nicholas L. Rodenhouse

    2012-01-01

    Evaluations of the local effects of global change are often confounded by the interactions of natural and anthropogenic factors that overshadow the effects of climate changes on ecosystems. Long-term watershed and natural elevation gradient studies at the Hubbard Brook Experimental Forest and in the surrounding region show surprising results demonstrating the effects...

  5. Complex terrain and wind lidars

    Energy Technology Data Exchange (ETDEWEB)

    Bingoel, F.

    2009-08-15

    This thesis includes the results of a PhD study about complex terrain and wind lidars. The study mostly focuses on hilly and forested areas. Lidars have been used in combination with cups, sonics and vanes, to reach the desired vertical measurement heights. Several experiments are performed in complex terrain sites and the measurements are compared with two different flow models; a linearised flow model LINCOM and specialised forest model SCADIS. In respect to the lidar performance in complex terrain, the results showed that horizontal wind speed errors measured by a conically scanning lidar can be of the order of 3-4% in moderately-complex terrain and up to 10% in complex terrain. The findings were based on experiments involving collocated lidars and meteorological masts, together with flow calculations over the same terrains. The lidar performance was also simulated with the commercial software WAsP Engineering 2.0 and was well predicted except for some sectors where the terrain is particularly steep. Subsequently, two experiments were performed in forested areas; where the measurements are recorded at a location deep-in forest and at the forest edge. Both sites were modelled with flow models and the comparison of the measurement data with the flow model outputs showed that the mean wind speed calculated by LINCOM model was only reliable between 1 and 2 tree height (h) above canopy. The SCADIS model reported better correlation with the measurements in forest up to approx6h. At the forest edge, LINCOM model was used by allocating a slope half-in half out of the forest based on the suggestions of previous studies. The optimum slope angle was reported as 17 deg.. Thus, a suggestion was made to use WAsP Engineering 2.0 for forest edge modelling with known limitations and the applied method. The SCADIS model worked better than the LINCOM model at the forest edge but the model reported closer results to the measurements at upwind than the downwind and this should be

  6. Modeling the Complex Impacts of Timber Harvests to Find Optimal Management Regimes for Amazon Tidal Floodplain Forests.

    Science.gov (United States)

    Fortini, Lucas B; Cropper, Wendell P; Zarin, Daniel J

    2015-01-01

    At the Amazon estuary, the oldest logging frontier in the Amazon, no studies have comprehensively explored the potential long-term population and yield consequences of multiple timber harvests over time. Matrix population modeling is one way to simulate long-term impacts of tree harvests, but this approach has often ignored common impacts of tree harvests including incidental damage, changes in post-harvest demography, shifts in the distribution of merchantable trees, and shifts in stand composition. We designed a matrix-based forest management model that incorporates these harvest-related impacts so resulting simulations reflect forest stand dynamics under repeated timber harvests as well as the realities of local smallholder timber management systems. Using a wide range of values for management criteria (e.g., length of cutting cycle, minimum cut diameter), we projected the long-term population dynamics and yields of hundreds of timber management regimes in the Amazon estuary, where small-scale, unmechanized logging is an important economic activity. These results were then compared to find optimal stand-level and species-specific sustainable timber management (STM) regimes using a set of timber yield and population growth indicators. Prospects for STM in Amazonian tidal floodplain forests are better than for many other tropical forests. However, generally high stock recovery rates between harvests are due to the comparatively high projected mean annualized yields from fast-growing species that effectively counterbalance the projected yield declines from other species. For Amazonian tidal floodplain forests, national management guidelines provide neither the highest yields nor the highest sustained population growth for species under management. Our research shows that management guidelines specific to a region's ecological settings can be further refined to consider differences in species demographic responses to repeated harvests. In principle, such fine

  7. Modeling the complex impacts of timber harvests to find optimal management regimes for Amazon tidal floodplain forests

    Science.gov (United States)

    Fortini, Lucas B.; Cropper, Wendell P.; Zarin, Daniel J.

    2015-01-01

    At the Amazon estuary, the oldest logging frontier in the Amazon, no studies have comprehensively explored the potential long-term population and yield consequences of multiple timber harvests over time. Matrix population modeling is one way to simulate long-term impacts of tree harvests, but this approach has often ignored common impacts of tree harvests including incidental damage, changes in post-harvest demography, shifts in the distribution of merchantable trees, and shifts in stand composition. We designed a matrix-based forest management model that incorporates these harvest-related impacts so resulting simulations reflect forest stand dynamics under repeated timber harvests as well as the realities of local smallholder timber management systems. Using a wide range of values for management criteria (e.g., length of cutting cycle, minimum cut diameter), we projected the long-term population dynamics and yields of hundreds of timber management regimes in the Amazon estuary, where small-scale, unmechanized logging is an important economic activity. These results were then compared to find optimal stand-level and species-specific sustainable timber management (STM) regimes using a set of timber yield and population growth indicators. Prospects for STM in Amazonian tidal floodplain forests are better than for many other tropical forests. However, generally high stock recovery rates between harvests are due to the comparatively high projected mean annualized yields from fast-growing species that effectively counterbalance the projected yield declines from other species. For Amazonian tidal floodplain forests, national management guidelines provide neither the highest yields nor the highest sustained population growth for species under management. Our research shows that management guidelines specific to a region’s ecological settings can be further refined to consider differences in species demographic responses to repeated harvests. In principle, such fine

  8. Modeling the Complex Impacts of Timber Harvests to Find Optimal Management Regimes for Amazon Tidal Floodplain Forests

    Science.gov (United States)

    Fortini, Lucas B.; Cropper, Wendell P.; Zarin, Daniel J.

    2015-01-01

    At the Amazon estuary, the oldest logging frontier in the Amazon, no studies have comprehensively explored the potential long-term population and yield consequences of multiple timber harvests over time. Matrix population modeling is one way to simulate long-term impacts of tree harvests, but this approach has often ignored common impacts of tree harvests including incidental damage, changes in post-harvest demography, shifts in the distribution of merchantable trees, and shifts in stand composition. We designed a matrix-based forest management model that incorporates these harvest-related impacts so resulting simulations reflect forest stand dynamics under repeated timber harvests as well as the realities of local smallholder timber management systems. Using a wide range of values for management criteria (e.g., length of cutting cycle, minimum cut diameter), we projected the long-term population dynamics and yields of hundreds of timber management regimes in the Amazon estuary, where small-scale, unmechanized logging is an important economic activity. These results were then compared to find optimal stand-level and species-specific sustainable timber management (STM) regimes using a set of timber yield and population growth indicators. Prospects for STM in Amazonian tidal floodplain forests are better than for many other tropical forests. However, generally high stock recovery rates between harvests are due to the comparatively high projected mean annualized yields from fast-growing species that effectively counterbalance the projected yield declines from other species. For Amazonian tidal floodplain forests, national management guidelines provide neither the highest yields nor the highest sustained population growth for species under management. Our research shows that management guidelines specific to a region’s ecological settings can be further refined to consider differences in species demographic responses to repeated harvests. In principle, such fine

  9. Europium(III) complexes of polyfunctional carboxylic acids: Luminescence probes of possible binding sites in fulvic acid

    Energy Technology Data Exchange (ETDEWEB)

    Lee, B.H.; Chung, K.H.; Shin, H.S.; Moon, H. [Korea Advanced Inst. of Science and Technology, Taejon (Korea, Republic of). Dept. of Chemistry; Park, Y.J. [Korea Atomic Energy Research Inst., Taejon (Korea, Republic of)

    1997-04-15

    The {sup 7}F{sub 0} {r_arrow} {sup 5}D{sub 0} excitation spectra of Eu(III) complexed with polyfunctional dicarboxylic acid containing neutral O, N, and S donors were investigated using Eu(III) luminescence spectroscopy. Three distinct peaks are seen in the excitation spectra in the Eu(III)-diglycolic acid (ODA) and Eu(III)-iminodiacetic acid (IMDA) systems showing the formation of three species, where each tridentate ODA {sup 2{minus}} and IMDA{sup 2{minus}} displace approximately three coordinated water molecules; however, the central S donor of Eu(III)-thiodiglycolate and 2,5-thiophenedicarboxylate are shown to be poor chelators for free Eu{sup 3+} ions. The neutral O and N donors in combination with neighboring carboxylates may form strong metal chelation sites on fulvic acid.

  10. Contrasting winter and summer VOC mixing ratios at a forest site in the Western Mediterranean Basin: the effect of local biogenic emissions

    Directory of Open Access Journals (Sweden)

    R. Seco

    2011-12-01

    Full Text Available Atmospheric volatile organic compounds (VOCs are involved in ozone and aerosol generation, thus having implications for air quality and climate. VOCs and their emissions by vegetation also have important ecological roles as they can protect plants from stresses and act as communication cues between plants and between plants and animals. In spite of these key environmental and biological roles, the reports on seasonal and daily VOC mixing ratios in the literature for Mediterranean natural environments are scarce.

    We conducted seasonal (winter and summer measurements of VOC mixing ratios in an elevated (720 m a.s.l. holm oak Mediterranean forest site near the metropolitan area of Barcelona (NE Iberian Peninsula. Methanol was the most abundant compound among all the VOCs measured in both seasons. While aromatic VOCs showed almost no seasonal variability, short-chain oxygenated VOCs presented higher mixing ratios in summer, presumably due to greater emission by vegetation and increased photochemistry, both enhanced by the high temperatures and solar radiation in summer. Isoprenoid VOCs showed the biggest seasonal change in mixing ratios: they increased by one order of magnitude in summer, as a result of the vegetation's greater physiological activity and emission rates. The maximum diurnal concentrations of ozone increased in summer too, most likely due to more intense photochemical activity and the higher levels of VOCs in the air.

    The daily variation of VOC mixing ratios was mainly governed by the wind regime of the mountain, as the majority of the VOC species analyzed followed a very similar diel cycle. Mountain and sea breezes that develop after sunrise advect polluted air masses to the mountain. These polluted air masses had previously passed over the urban and industrial areas surrounding the Barcelona metropolitan area, where they were enriched in NOx and in VOCs of biotic and abiotic origin. Moreover, these

  11. Contrasting winter and summer VOC mixing ratios at a forest site in the Western Mediterranean Basin: the effect of local biogenic emissions

    Science.gov (United States)

    Seco, R.; Peñuelas, J.; Filella, I.; Llusià, J.; Molowny-Horas, R.; Schallhart, S.; Metzger, A.; Müller, M.; Hansel, A.

    2011-12-01

    Atmospheric volatile organic compounds (VOCs) are involved in ozone and aerosol generation, thus having implications for air quality and climate. VOCs and their emissions by vegetation also have important ecological roles as they can protect plants from stresses and act as communication cues between plants and between plants and animals. In spite of these key environmental and biological roles, the reports on seasonal and daily VOC mixing ratios in the literature for Mediterranean natural environments are scarce. We conducted seasonal (winter and summer) measurements of VOC mixing ratios in an elevated (720 m a.s.l.) holm oak Mediterranean forest site near the metropolitan area of Barcelona (NE Iberian Peninsula). Methanol was the most abundant compound among all the VOCs measured in both seasons. While aromatic VOCs showed almost no seasonal variability, short-chain oxygenated VOCs presented higher mixing ratios in summer, presumably due to greater emission by vegetation and increased photochemistry, both enhanced by the high temperatures and solar radiation in summer. Isoprenoid VOCs showed the biggest seasonal change in mixing ratios: they increased by one order of magnitude in summer, as a result of the vegetation's greater physiological activity and emission rates. The maximum diurnal concentrations of ozone increased in summer too, most likely due to more intense photochemical activity and the higher levels of VOCs in the air. The daily variation of VOC mixing ratios was mainly governed by the wind regime of the mountain, as the majority of the VOC species analyzed followed a very similar diel cycle. Mountain and sea breezes that develop after sunrise advect polluted air masses to the mountain. These polluted air masses had previously passed over the urban and industrial areas surrounding the Barcelona metropolitan area, where they were enriched in NOx and in VOCs of biotic and abiotic origin. Moreover, these polluted air masses receive additional biogenic

  12. Forest-Site Planning and Prescription for Control of Annosus Root Disease in Ponderosa Pine and Mixed Conifer Stands

    Science.gov (United States)

    John Nesbitt

    1989-01-01

    In order to successfully combat pathogens such as annosus root rot, the land manager and pathologist must have periodic dialogue about the pest, its identification, effects, impacts, and cures. The author presents four important topics to structure this dialogue. These are (1) training from the pathologist to the silviculturist or other land manager, (2) site specific...

  13. The Social and Environmental Impacts of Biofuel Feedstock Cultivation: Evidence from Multi-Site Research in the Forest Frontier

    Directory of Open Access Journals (Sweden)

    Laura German

    2011-09-01

    Full Text Available Preoccupation with global energy supplies and climate change in the global North, and a desire to improve the balance of trade and capture value in the emerging carbon market by developing countries, together place biofuels firmly on the map of global land use change. Much of this recent land use change is occurring in developing countries where large agro-ecologically suitable tracts of land may be accessed at lower economic and opportunity cost. This is leading to the gradual penetration of commercial crops that provide suitable biofuel feedstocks (e.g., sugarcane, soybean, oil palm, jatropha into rural communities and forested landscapes throughout many areas of the global South. Expansion of biofuel feedstock cultivation in developing countries is widely embraced by producer country governments as a means to achieve energy security and stimulate rural economic development through employment and smallholder market integration. It is also expected that foreign and domestic investments in biofuel feedstock cultivation will lead to positive economic spillovers from knowledge transfer and investor contributions to social and physical infrastructure. While biofuel feedstocks are expanding through large industrial-scale plantations and smallholder production alike, the expansion of industrial-scale production systems has been countered by a critical response by civil society actors concerned about the implications for rural livelihoods, customary land rights, and the environmental effects of biofuel feedstock cultivation. To date, however, limited data exist to demonstrate the conditions under which widely anticipated economic and climate change mitigation benefits accrue in practice, and the implications of these developments for forests, local livelihoods, and the climate change mitigation potential of biofuels. In such a situation, debates are easily polarized into those for and against biofuels. This special issue seeks to nuance this debate by

  14. Genome-wide identification and characterization of Notch transcription complex-binding sequence-paired sites in leukemia cells.

    Science.gov (United States)

    Severson, Eric; Arnett, Kelly L; Wang, Hongfang; Zang, Chongzhi; Taing, Len; Liu, Hudan; Pear, Warren S; Shirley Liu, X; Blacklow, Stephen C; Aster, Jon C

    2017-05-02

    Notch transcription complexes (NTCs) drive target gene expression by binding to two distinct types of genomic response elements, NTC monomer-binding sites and sequence-paired sites (SPSs) that bind NTC dimers. SPSs are conserved and have been linked to the Notch responsiveness of a few genes. To assess the overall contribution of SPSs to Notch-dependent gene regulation, we determined the DNA sequence requirements for NTC dimerization using a fluorescence resonance energy transfer (FRET) assay and applied insights from these in vitro studies to Notch-"addicted" T cell acute lymphoblastic leukemia (T-ALL) cells. We found that SPSs contributed to the regulation of about a third of direct Notch target genes. Although originally described in promoters, SPSs are present mainly in long-range enhancers, including an enhancer containing a newly described SPS that regulates HES5 expression. Our work provides a general method for identifying SPSs in genome-wide data sets and highlights the widespread role of NTC dimerization in Notch-transformed leukemia cells. Copyright © 2017, American Association for the Advancement of Science.

  15. Structure of a Major Antigenic Site on the Respiratory Syncytial Virus Fusion Glycoprotein in Complex with Neutralizing Antibody 101F

    Energy Technology Data Exchange (ETDEWEB)

    McLellan, Jason S.; Chen, Man; Chang, Jung-San; Yang, Yongping; Kim, Albert; Graham, Barney S.; Kwong, Peter D. (NIH)

    2010-11-19

    Respiratory syncytial virus (RSV) is a major cause of pneumonia and bronchiolitis in infants and elderly people. Currently there is no effective vaccine against RSV, but passive prophylaxis with neutralizing antibodies reduces hospitalizations. To investigate the mechanism of antibody-mediated RSV neutralization, we undertook structure-function studies of monoclonal antibody 101F, which binds a linear epitope in the RSV fusion glycoprotein. Crystal structures of the 101F antigen-binding fragment in complex with peptides from the fusion glycoprotein defined both the extent of the linear epitope and the interactions of residues that are mutated in antibody escape variants. The structure allowed for modeling of 101F in complex with trimers of the fusion glycoprotein, and the resulting models suggested that 101F may contact additional surfaces located outside the linear epitope. This hypothesis was supported by surface plasmon resonance experiments that demonstrated 101F bound the peptide epitope {approx}16,000-fold more weakly than the fusion glycoprotein. The modeling also showed no substantial clashes between 101F and the fusion glycoprotein in either the pre- or postfusion state, and cell-based assays indicated that 101F neutralization was not associated with blocking virus attachment. Collectively, these results provide a structural basis for RSV neutralization by antibodies that target a major antigenic site on the fusion glycoprotein.

  16. Effects of temperature, soil substrate, and microbial community on carbon mineralization across three climatically contrasting forest sites.

    Science.gov (United States)

    Tang, Zuoxin; Sun, Xiaolu; Luo, Zhongkui; He, Nianpeng; Sun, Osbert Jianxin

    2018-01-01

    How biotic and abiotic factors influence soil carbon (C) mineralization rate (RS) has recently emerged as one of the focal interests in ecological studies. To determine the relative effects of temperature, soil substrate and microbial community on Rs, we conducted a laboratory experiment involving reciprocal microbial inoculations of three zonal forest soils, and measured RS over a 61-day period at three temperatures (5, 15, and 25°C). Results show that both Rs and the cumulative emission of C (Rcum), normalized to per unit soil organic C (SOC), were significantly affected by incubation temperature, soil substrate, microbial inoculum treatment, and their interactions (p soil substrate, microbial inoculum treatment, and their interaction all significantly affected both Rs (p soil substrate was much stronger than others. There was no consistent pattern of thermal adaptation in microbial decomposition of SOC in the reciprocal inoculations. Moreover, when different sources of microbial inocula were introduced to the same soil substrate, the microbial community structure converged with incubation without altering the overall soil enzyme activities; when different types of soil substrate were inoculated with the same sources of microbial inocula, both the microbial community structure and soil enzyme activities diverged. Overall, temperature plays a predominant role in affecting Rs and Rcum, while soil substrate determines the mineralizable SOC under given conditions. The role of microbial community in driving SOC mineralization is weaker than that of climate and soil substrate, because soil microbial community is both affected, and adapts to, climatic factors and soil matrix.

  17. Integrated approach to ecohydrology of semi-arid sites in areas of complex topography and biome transitions

    Science.gov (United States)

    Gutierrez, H. A.; Ivanov, V. Y.; Vivoni, E. R.; Bras, R. L.

    2005-05-01

    Vegetation constitutes an essential link in the hydrologic cycle at the land surface - atmosphere interface. Vegetation exerts a predominant control over the partition of rainfall into soil infiltration and evapotranspiration and determines to a great extent the water budget of entire regions. Conversely, water availability has a strong influence on the vegetation dynamics, including growth rates and overall health. In semiarid areas, changes in vegetation composition can follow slight variations in climate-derived moisture availability that, in turn, have a feedback effect on the surface water and energy balance. In this study, we present an integrated approach for studying the ecohydrology of semiarid regions characterized by complex topography and transitions between different vegetation life forms (grasses, shrubs, trees). We first present a set of hypotheses on the interaction between vegetation, landscape conditions, and climate variability in biome transitions zones. These hypotheses will be tested via the combination of numerical modeling and field data collection in the Sevilleta National Wildlife Refuge, central New Mexico. The field site is a first-order drainage basin consisting of two opposing hillslopes that differentially support a shrub-grass ecosystem and a conifer-grass community. Our modeling approaches consist of an ecohydrological module coupled to a 1-D vadose zone model as well as a more complex 3-D ecohydrological framework capable of simulating full vegetation dynamics at the watershed scale. The field instrumentation and model development efforts will be used synergistically to improve our understanding of the ecohydrology of semiarid complex watersheds. We then present an analysis of the ecohydrological model simulations driven by short- term meteorological data (~10 years) as well as by longer term, synthetically-generated climate scenarios. In particular, we will focus on the response of different vegetation communities to the

  18. Phenolic compounds as a tool of bioindication for novel forest decline at numerous spruce tree sites in Germany

    Energy Technology Data Exchange (ETDEWEB)

    Richter, C.M. [Mainz Univ. (Germany). Inst. fuer Allgemeine Botanik; Eis, U. [Mainz Univ. (Germany). Inst. fuer Allgemeine Botanik; Wild, A. [Mainz Univ. (Germany). Inst. fuer Allgemeine Botanik

    1996-01-01

    Within a project that applied biochemical criteria to the diagnosis of damage to Norway spruce, 43 sites in western and eastern Germany showing only moderate tree damage were screened for the amounts of methanol soluble phenolic compounds in spruce needles. The concentrations of most of the main compounds - especially catechin - positively correlated with needle loss and the altitude of the site. It was also found that it is necessary to differentiate between trees younger and older than 60 years of age. The correlations between the increase of the phenolic compounds studied and the needle loss or the damage class are stronger in the younger trees, possibly implicating differences in metabolic state or disturbances in protectective mechanisms in the older trees. (orig.)

  19. Tripodal bis(imidazole) thioether copper(I) complexes: mimics of the Cu(M) site of copper hydroxylase enzymes.

    Science.gov (United States)

    Zhou, Lei; Powell, Douglas; Nicholas, Kenneth M

    2007-09-17

    Tripodal bis(imidazole) thioether ligands, (N-methyl-4,5-diphenyl-2-imidazolyl)2C(OR)C(CH3)2SR' (BIT(OR,SR'); R = H, CH3; R' = CH3, C(CH3)3, C(C6H5)3), have been prepared, offering the same N2S donor atom set as the CuM binding site of the hydroxylase enzymes, dopamine beta hydroxylase and peptidylglycine hydroxylating monooxygenase. Isolable copper(I) complexes of the type [(BIT(OR,SMe))Cu(CO)]PF6 (3a and 3b) are produced in reactions of the respective tripodal ligands 1a (R = H) and 1b (R = Me) with [Cu(CH3CN)4]PF6 in CH2Cl2 under CO (1 atm); the pyramidal structure of 3a has been determined crystallographically. The infrared (IR) nu(CO)'s of 3a and 3b (L = CO) are comparable to those of the Cu(M)-carbonylated enzymes, indicating similar electronic character at the copper centers. The reaction of [(BIT(OH,SMe))Cu(CH3CN)]PF6 (2a) with dioxygen produces [(BIT(O,SOMe))2Cu2(DMF)2](PF6)2 (4), whose X-ray structure revealed the presence of bridging BIT-alkoxo ligands and terminal -SOMe groups. In contrast, oxygenation of 2b (R = Me) affords crystallographically defined [(BIT(OMe,SMe))2Cu2(mu-OH)2](OTf)2 (5), in which the copper centers are oxygenated without accompanying sulfur oxidation. Complex 5 in DMF is transformed into five-coordinate, mononuclear [CuII(BIT(OMe,SMe))(DMF)2](PF6)2 (6). The sterically hindered BIT(OR,SR') ligands 9 and 10 (R' = t-Bu; R = H, Me) and 11 and 12 (R' = CPh3; R = H, Me) were also prepared and examined for copper coordination/oxygenation. Oxygenation of copper(I) complex 13b derived from the BIT(OMe,SBu-t) ligand is slow, relative to 2b, producing a mixture of (BIT(OMe,SBu-t))2Cu2(mu-OH)2-type complexes 14b and 15b in which the -SBu-t group is uncoordinated; one of these complexes (15b) has been ortho-oxygenated on a neighboring aryl group according to the X-ray analysis and characterization of the free ligand. Oxygenation of the copper(I) complex derived from BIT(OMe,SCPh3) ligand 12 produces a novel dinuclear disulfide complex, [(BIT

  20. Environmental Impacts of Forest Road Construction on Mountainous Terrain

    Directory of Open Access Journals (Sweden)

    Erhan Caliskan

    2013-03-01

    Full Text Available Forest roads are the base infrastructure foundation of forestry operations. These roads entail a complex engineering effort because they can cause substantial environmental damage to forests and include a high-cost construction. This study was carried out in four sample sites of Giresun, Trabzon(2 and Artvin Forest Directorate, which is in the Black Sea region of Turkey. The areas have both steep terrain (30-50% gradient and very steep terrain (51-80% gradient. Bulldozers and hydraulic excavators were determined to be the main machines for forest road construction, causing environmental damage and cross sections in mountainous areas.As a result of this study, the percent damage to forests was determined as follows: on steep terrain, 21% of trees were damaged by excavators and 33% of trees were damaged by bulldozers during forest road construction, and on very steep terrain, 27% of trees were damaged by excavators and 44% of trees were damaged by bulldozers during forest road construction. It was also determined that on steep terrain, when excavators were used, 12.23% less forest area was destroyed compared with when bulldozers were used and 16.13% less area was destroyed by excavators on very steep terrain. In order to reduce the environmental damage on the forest ecosystem, especially in steep terrains, hydraulic excavators should replace bulldozers in forest road construction activities.

  1. Denuder/filter sampling of organic acids and organosulfates at urban and boreal forest sites: Gas/particle distribution and possible sampling artifacts

    Science.gov (United States)

    Kristensen, Kasper; Bilde, Merete; Aalto, Pasi P.; Petäjä, Tuukka; Glasius, Marianne

    2016-04-01

    Carboxylic acids and organosulfates comprise an important fraction of atmospheric secondary organic aerosols formed from both anthropogenic and biogenic precursors. The partitioning of these compounds between the gas and particle phase is still unclear and further research is warranted to better understand the abundance and effect of organic acids and organosulfates on the formation and properties of atmospheric aerosols. This work compares atmospheric aerosols collected at an urban and a boreal forest site using two side-by-side sampling systems; a high volume sampler (HVS) and a low volume (LVS) denuder/filter sampling system allowing for separate collection of gas- and particle-phase organics. All particle filters and denuder samples were collected at H.C. Andersen Boulevard (HCAB), Copenhagen, Denmark in the summer of 2010, and at the remote boreal forest site at Hyytiälä forestry field station in Finland in the summer of 2012. The chemical composition of gas- and particle-phase secondary organic aerosol was investigated by ultra-high performance liquid chromatography/electrospray ionization quadrupole time-of-flight mass spectrometry (UPLC/ESI-Q-TOFMS), with a focus on carboxylic acids and organosulfates. Results show gas-phase concentrations higher than those observed in the particle phase by a factor of 5-6 in HCAB 2010 and 50-80 in Hyytiälä 2012. Although abundant in the particle phase, no organosulfates were detected in the gas phase at either site. Through a comparison of samples collected by the HVS and the LVS denuder/filter sampling system we evaluate the potential artifacts associated with sampling of atmospheric aerosols. Such comparison shows that particle phase concentrations of semi-volatile organic acids obtained from the filters collected by HVS are more than two times higher than concentrations obtained from filters collected using LVS denuder/filter system. In most cases, higher concentrations of organosulfates are observed in particles

  2. Site exploration for rock-mechanics field tests in the Grouse Canyon Member, Belted Range Tuff, U12g Tunnel Complex, Nevada Test Site

    Energy Technology Data Exchange (ETDEWEB)

    Langkopf, B.S.; Eshom, E.

    1982-02-01

    This report describes site exploration work completed in support of planned rock-mechanics field tests in the Grouse Canyon Member of the Belted Range Ruff at Nevada Test Site`s, G-Tunnel. As part of this work, the Rock Mechanics Drift (RMD) and the Rock Mass Property Alcove (RMPA) were mined and three coreholes drilled. The results of mapping and corehole logging are displayed, described, and analyzed.

  3. 78 FR 34035 - Forest Resource Coordinating Committee

    Science.gov (United States)

    2013-06-06

    ... Forest Service Forest Resource Coordinating Committee AGENCY: Forest Service, USDA. ACTION: Notice of meeting. SUMMARY: The Forest Resource Coordinating Committee will meet via teleconference every month on... conference call will be posted to the Forest Resource Coordinating Committee Web site, http://www.fs.fed.us...

  4. Applications of site-specific labeling to study HAMLET, a tumoricidal complex of α-lactalbumin and oleic acid.

    Directory of Open Access Journals (Sweden)

    Natalia Mercer

    Full Text Available Alpha-lactalbumin (α-LA is a calcium-bound mammary gland-specific protein that is found in milk. This protein is a modulator of β1,4-galactosyltransferase enzyme, changing its acceptor specificity from N-acetyl-glucosamine to glucose, to produce lactose, milk's main carbohydrate. When calcium is removed from α-LA, it adopts a molten globule form, and this form, interestingly, when complexed with oleic acid (OA acquires tumoricidal activity. Such a complex made from human α-LA (hLA is known as HAMLET (Human A-lactalbumin Made Lethal to Tumor cells, and its tumoricidal activity has been well established.In the present work, we have used site-specific labeling, a technique previously developed in our laboratory, to label HAMLET with biotin, or a fluoroprobe for confocal microscopy studies. In addition to full length hLA, the α-domain of hLA (αD-hLA alone is also included in the present study. We have engineered these proteins with a 17-amino acid C-terminal extension (hLA-ext and αD-hLA-ext. A single Thr residue in this extension is glycosylated with 2-acetonyl-galactose (C2-keto-galactose using polypeptide-α-N-acetylgalactosaminyltransferase II (ppGalNAc-T2 and further conjugated with aminooxy-derivatives of fluoroprobe or biotin molecules.We found that the molten globule form of hLA and αD-hLA proteins, with or without C-terminal extension, and with and without the conjugated fluoroprobe or biotin molecule, readily form a complex with OA and exhibits tumoricidal activity similar to HAMLET made with full-length hLA protein. The confocal microscopy studies with fluoroprobe-labeled samples show that these proteins are internalized into the cells and found even in the nucleus only when they are complexed with OA. The HAMLET conjugated with a single biotin molecule will be a useful tool to identify the cellular components that are involved with it in the tumoricidal activity.

  5. Applications of site-specific labeling to study HAMLET, a tumoricidal complex of α-lactalbumin and oleic acid.

    Science.gov (United States)

    Mercer, Natalia; Ramakrishnan, Boopathy; Boeggeman, Elizabeth; Qasba, Pradman K

    2011-01-01

    Alpha-lactalbumin (α-LA) is a calcium-bound mammary gland-specific protein that is found in milk. This protein is a modulator of β1,4-galactosyltransferase enzyme, changing its acceptor specificity from N-acetyl-glucosamine to glucose, to produce lactose, milk's main carbohydrate. When calcium is removed from α-LA, it adopts a molten globule form, and this form, interestingly, when complexed with oleic acid (OA) acquires tumoricidal activity. Such a complex made from human α-LA (hLA) is known as HAMLET (Human A-lactalbumin Made Lethal to Tumor cells), and its tumoricidal activity has been well established. In the present work, we have used site-specific labeling, a technique previously developed in our laboratory, to label HAMLET with biotin, or a fluoroprobe for confocal microscopy studies. In addition to full length hLA, the α-domain of hLA (αD-hLA) alone is also included in the present study. We have engineered these proteins with a 17-amino acid C-terminal extension (hLA-ext and αD-hLA-ext). A single Thr residue in this extension is glycosylated with 2-acetonyl-galactose (C2-keto-galactose) using polypeptide-α-N-acetylgalactosaminyltransferase II (ppGalNAc-T2) and further conjugated with aminooxy-derivatives of fluoroprobe or biotin molecules. We found that the molten globule form of hLA and αD-hLA proteins, with or without C-terminal extension, and with and without the conjugated fluoroprobe or biotin molecule, readily form a complex with OA and exhibits tumoricidal activity similar to HAMLET made with full-length hLA protein. The confocal microscopy studies with fluoroprobe-labeled samples show that these proteins are internalized into the cells and found even in the nucleus only when they are complexed with OA. The HAMLET conjugated with a single biotin molecule will be a useful tool to identify the cellular components that are involved with it in the tumoricidal activity.

  6. 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.

  7. Disparate effects of global-change drivers on mountain conifer forests: warming-induced growth enhancement in young trees vs. CO2 fertilization in old trees from wet sites.

    Science.gov (United States)

    Camarero, J Julio; Gazol, Antonio; Galván, Juan Diego; Sangüesa-Barreda, Gabriel; Gutiérrez, Emilia

    2015-02-01

    Theory predicts that the postindustrial rise in the concentration of CO2 in the atmosphere (c(a)) should enhance tree growth either through a direct fertilization effect or indirectly by improving water use efficiency in dry areas. However, this hypothesis has received little support in cold-limited and subalpine forests where positive growth responses to either rising ca or warmer temperatures are still under debate. In this study, we address this issue by analyzing an extensive dendrochronological network of high-elevation Pinus uncinata forests in Spain (28 sites, 544 trees) encompassing the whole biogeographical extent of the species. We determine if the basal area increment (BAI) trends are linked to climate warming and increased c(a) by focusing on region- and age-dependent responses. The largest improvement in BAI over the past six centuries occurred during the last 150 years affecting young trees and being driven by recent warming. Indeed, most studied regions and age classes presented BAI patterns mainly controlled by temperature trends, while growing-season precipitation was only relevant in the driest sites. Growth enhancement was linked to rising ca in mature (151-300 year-old trees) and old-mature trees (301-450 year-old trees) from the wettest sites only. This finding implies that any potential fertilization effect of elevated c(a) on forest growth is contingent on tree features that vary with ontogeny and it depends on site conditions (for instance water availability). Furthermore, we found widespread growth decline in drought-prone sites probably indicating that the rise in ca did not compensate for the reduction in water availability. Thus, warming-triggered drought stress may become a more important direct driver of growth than rising ca in similar subalpine forests. We argue that broad approaches in biogeographical and temporal terms are required to adequately evaluate any effect of rising c(a) on forest growth. © 2014 John Wiley & Sons Ltd.

  8. Mapping of the binding sites involved in PSP94-CRISP-3 interaction by molecular dissection of the complex.

    Science.gov (United States)

    Breed, Ananya A; Gomes, Amanda; Roy, Binita Sur; Mahale, Smita D; Pathak, Bhakti R

    2013-04-01

    Human Prostate Secretory Protein of 94 amino acids (PSP94) has been shown to bind human CRISP-3 (cysteine-rich secretory protein 3) with very high affinity. CRISP-3 belongs to the CRISP family of proteins having a PR-1 (pathogenesis related protein 1) domain at its N-terminal and ion channel regulatory (ICR) domain at its C-terminal connected by a hinge region. Functional significance of this complex is not yet known. In order to identify the residues and/or regions involved in PSP94-CRISP-3 interaction, site-directed mutagenesis was employed. Effect of the mutations on the interaction was studied by co-immunoprecipitation (Co-IP). For PSP94, amino acids Y(3), F(4), P(56) and the C-terminal β-strand were found to be crucial for interacting with CRISP-3. A disulfide bond between the two domains of PSP94 (C(37)A-C(73)A) was also important for this interaction. In case of CRISP-3, the N-terminal domain alone could not maintain a strong interaction with PSP94 but it required presence of the hinge region and not the C-terminal domain. Apart from CRISP-3, CRISP-2 was also found to interact with human PSP94. Based on our findings the most likely model of PSP94-CRISP-3 complex has been proposed. The terminal β-strands of PSP94 contact the first α-helix and the hinge region of CRISP-3. Involvement of the hinge region of CRISPs in interaction with PSP94 may affect the domain movement of CRISPs essential for the ion-channel regulatory activity resulting in inhibition of this activity. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. A multivariate decision tree analysis of biophysical factors in tropical forest fire occurrence

    Science.gov (United States)

    Rey S. Ofren; Edward Harvey

    2000-01-01

    A multivariate decision tree model was used to quantify the relative importance of complex hierarchical relationships between biophysical variables and the occurrence of tropical forest fires. The study site is the Huai Kha Kbaeng wildlife sanctuary, a World Heritage Site in northwestern Thailand where annual fires are common and particularly destructive. Thematic...

  10. Validating MODIS and Sentinel-2 NDVI Products at a Temperate Deciduous Forest Site Using Two Independent Ground-Based Sensors.

    Science.gov (United States)

    Lange, Maximilian; Dechant, Benjamin; Rebmann, Corinna; Vohland, Michael; Cuntz, Matthias; Doktor, Daniel

    2017-08-11

    Quantifying the accuracy of remote sensing products is a timely endeavor given the rapid increase in Earth observation missions. A validation site for Sentinel-2 products was hence established in central Germany. Automatic multispectral and hyperspectral sensor systems were installed in parallel with an existing eddy covariance flux tower, providing spectral information of the vegetation present at high temporal resolution. Normalized Difference Vegetation Index (NDVI) values from ground-based hyperspectral and multispectral sensors were compared with NDVI products derived from Sentinel-2A and Moderate-resolution Imaging Spectroradiometer (MODIS). The influence of different spatial and temporal resolutions was assessed. High correlations and similar phenological patterns between in situ and satellite-based NDVI time series demonstrated the reliability of satellite-based phenological metrics. Sentinel-2-derived metrics showed better agreement with in situ measurements than MODIS-derived metrics. Dynamic filtering with the best index slope extraction algorithm was nevertheless beneficial for Sentinel-2 NDVI time series despite the availability of quality information from the atmospheric correction procedure.

  11. Biogenic emissions and ambient concentrations of hydrocarbons, carbonyl compounds and organic acids from ponderosa pine and cottonwood trees at rural and forested sites in Central New Mexico

    Science.gov (United States)

    Villanueva-Fierro, Ignacio; Popp, Carl J.; Martin, Randal S.

    Direct emission rates of carbonyl compounds, carboxylic acids and hydrocarbons from Populus fremontil (cottonwood) and Pinus ponderosa (ponderosa pine) trees were studied during the summer of 1997. Ambient air concentrations of these compounds in the vicinity of the sampled trees were also identified and quantified. Study sites were Socorro, NM and Langmuir Laboratory, NM a rural and forested, high mountain site, respectively, located in Central New Mexico. A dynamic branch enclosure method was used to perform the sampling of tree emissions, that are given at standard atmospheric temperature of 303 K, and 1000 μmol m -2 s -1 PAR. Average emission rates of acetic and formic acid, respectively, from cottonwood were 470±540 and 310±300 ng g -1 h -1 and from ponderosa pine were 170±180 and 210±210 ng g -1 h -1. Formaldehyde and acetaldehyde average emission rates, respectively, from ponderosa pine were 500±400 and 250±190 ng g -1 h -1, and from cottonwood were 4070±3570 and 1190±1360 ng g -1 h -1. Cottonwood had an average isoprene emission rate of 9050±10700 ng g -1 h -1, while ponderosa pine had emission rates of α-pinene and β-pinene of 450±1100 and 520±1050 ng g -1 h -1, respectively. Total mass emissions of carbon compounds measured from cottonwood were four times larger than from ponderosa pine. Seasonal, diurnal, and temperature dependence of concentrations in ambient air and emission rates from trees are also discussed. Average ambient air concentrations of acetic and formic acid, respectively, were 2.7±3.8 and 0.7±0.9 ppbv for the rural site, and 1.7±2.0 and 0.6±0.5 ppbv for the mountain site. The average range of carbonyl compound concentrations in ambient air was from 0.3 to 3.4 ppbv for various carbonyl compounds with about 60% of the ambient carbonyls consisting of formaldehyde, acetaldehyde and acetone. Isoprene and monoterpene concentrations in ambient air were usually below the detection limit.

  12. Vegetation map for the Hakalau Forest Unit of the Big Island National Wildlife Refuge Complex on the island of Hawai‘i

    Science.gov (United States)

    Jacobi, James D.

    2017-01-01

    This vegetation map was produced to serve as an updated habitat base for management of natural resources of the Hakalau Forest Unit (HFU) of the Big Island National Wildlife Refuge Complex (Refuge) on the island of Hawai‘i. The map is based on a vegetation map originally produced as part of the U.S. Fish and Wildlife Service’s Hawai‘i Forest Bird Survey to depict the distribution, structure, and composition of plant communities on the island of Hawai‘i as they existed in 1977. The current map has been updated to represent current conditions of plant communities in the HFU, based on WorldView 2 imagery taken in 2012 and very-high-resolution imagery collected by Pictometry International from 2010 to 2014. Thirty-one detailed plant communities are identified on this map, and fourteen of these units are found within the boundaries of HFU. Additionally, the mapped units can be displayed as five tree canopy cover units, three moisture zones units, eight dominant tree species units, and four habitat status units by choosing the various fields to group the units from the map attribute table. This updated map will provide a foundation for the refinement and tracking of management actions on the Refuge for the near future, particularly as the habitats in this area are subject to projected climate change.

  13. Remote Sensing and Ethnobotanical Assessment of the Mangrove Forest Changes in the Navachiste-San Ignacio-Macapule Lagoon Complex, Sinaloa, Mexico

    Directory of Open Access Journals (Sweden)

    Rubi Hernández Cornejo

    2005-06-01

    Full Text Available The present study focuses on the Navachiste-San Ignacio-Macapule lagoon complex in northwest Mexico and evaluates the spatiotemporal change in the mangrove area over the last three decades using Landsat MSS and TM imagery. Local ethnobotanical uses of the mangrove forest and local perceptions about the status and recent development of the mangrove forest cover are also analyzed. The results of interviews with 54 inhabitants of four fishing villages in the study area indicated that, overall, Laguncularia racemosa is the most frequently used species in this region of the Mexican Pacific coast, where it serves as firewood and a construction material, particularly for walls and fences. The next-ranked species were Avicennia germinans, which is used for tea, and Rhizophora mangle, which is used for tanning; both these species also serve medicinal purposes. There was a discrepancy between the assessment of actual changes in the mangrove cover and what people perceived them to be. These findings are discussed from a socioeconomic (utilization and an ecological (functionality point of view and in relation to the use of remote sensing as a tool. The utilization pattern is also discussed against the background of mangrove cover variation.

  14. A Complex Network Theory Approach for the Spatial Distribution of Fire Breaks in Heterogeneous Forest Landscapes for the Control of Wildland Fires.

    Science.gov (United States)

    Russo, Lucia; Russo, Paola; Siettos, Constantinos I

    2016-01-01

    Based on complex network theory, we propose a computational methodology which addresses the spatial distribution of fuel breaks for the inhibition of the spread of wildland fires on heterogeneous landscapes. This is a two-level approach where the dynamics of fire spread are modeled as a random Markov field process on a directed network whose edge weights are determined by a Cellular Automata model that integrates detailed GIS, landscape and meteorological data. Within this framework, the spatial distribution of fuel breaks is reduced to the problem of finding network nodes (small land patches) which favour fire propagation. Here, this is accomplished by exploiting network centrality statistics. We illustrate the proposed approach through (a) an artificial forest of randomly distributed density of vegetation, and (b) a real-world case concerning the island of Rhodes in Greece whose major part of its forest was burned in 2008. Simulation results show that the proposed methodology outperforms the benchmark/conventional policy of fuel reduction as this can be realized by selective harvesting and/or prescribed burning based on the density and flammability of vegetation. Interestingly, our approach reveals that patches with spar