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Sample records for oligotrophic pine fen

  1. Reconstruction of annual carbon dynamics and balance for an oligotrophic pine fen

    Energy Technology Data Exchange (ETDEWEB)

    Alm, J; Silvola, J; Aaltonen, H [Joensuu Univ. (Finland). Dept. of Biology; Talanov, A; Ikkonen, E [Karelian Research Centre of Russian Academy of Sciences (Russian Federation). Inst. of Biology; Nykaenen, H; Martikainen, P J [National Public Health Inst. Kuopio (Finland). Dept. of Environmental Microbiology

    1997-12-31

    Atmospheric carbon dioxide (CO{sub 2}) is bound by mire vegetation in photosynthesis during the growing season, and is re-released by respiration of plants, soil animals and microorganisms consuming dead organic matter. A small proportion of annual primary production may fall below the water table to anoxic conditions and thus escapes the oxidative decomposition. Also from anoxic peat, carbon is released with clear seasonal and spatial variation as methane (CH{sub 4}.). The rate of carbon accumulation in peat depends on the annual inbalance of plant production and litter decomposition. Exchange of CO{sub 2} and CH{sub 4} between peat, vegetation and the atmosphere thus reflects the dynamics of carbon flows in the ecosystem. Net ecosystem CO{sub 2} exchange (PN), total CO{sub 2} release (RTOT) and CH{sub 4} release (D) from different treeless surfaces of low-sedge Sphagnum papillosum pine fen was studied in eastern Finland. (8 refs.)

  2. Reconstruction of annual carbon dynamics and balance for an oligotrophic pine fen

    Energy Technology Data Exchange (ETDEWEB)

    Alm, J.; Silvola, J.; Aaltonen, H. [Joensuu Univ. (Finland). Dept. of Biology; Talanov, A.; Ikkonen, E. [Karelian Research Centre of Russian Academy of Sciences (Russian Federation). Inst. of Biology; Nykaenen, H.; Martikainen, P.J. [National Public Health Inst. Kuopio (Finland). Dept. of Environmental Microbiology

    1996-12-31

    Atmospheric carbon dioxide (CO{sub 2}) is bound by mire vegetation in photosynthesis during the growing season, and is re-released by respiration of plants, soil animals and microorganisms consuming dead organic matter. A small proportion of annual primary production may fall below the water table to anoxic conditions and thus escapes the oxidative decomposition. Also from anoxic peat, carbon is released with clear seasonal and spatial variation as methane (CH{sub 4}.). The rate of carbon accumulation in peat depends on the annual inbalance of plant production and litter decomposition. Exchange of CO{sub 2} and CH{sub 4} between peat, vegetation and the atmosphere thus reflects the dynamics of carbon flows in the ecosystem. Net ecosystem CO{sub 2} exchange (PN), total CO{sub 2} release (RTOT) and CH{sub 4} release (D) from different treeless surfaces of low-sedge Sphagnum papillosum pine fen was studied in eastern Finland. (8 refs.)

  3. Carbon budget of oligotrophic mires in the Southern Taiga of Western Siberia under anthropogenic impact

    Science.gov (United States)

    Golovatskaya, Eugenia; Dyukarev, Egor

    2010-05-01

    Role of peatlands in the global greenhouse gases budget is highly relevant. According to present estimates peatlands in undisturbed conditions act as a sink for the atmospheric carbon. Anthropogenic impact on peatlands (melioration, changes in land use, influence of underground water catchments) results in water table lowering, changing in vegetation cover, and degradation of peat deposit. Peatlands could provide a significant positive feedback for climate changes if warming and peatlands drying stimulates bulk soil organic matter decomposition which enhances CO2 release to the atmosphere. Western Siberian peatlands usually represented big bog massifs. Big peatlands have higher stability to external influence. Small peatlands have all signs of big bogs but react on changes in environmental variables more quickly. The present study is devoted to investigation of primary carbon fluxes (CO2 emission and net primary productivity) and carbon balance at oligotrophic bogs in native condition (key area "Bakchar") and under anthropogenic impact (key area "Ob'-Tom'"). The key area "Bakchar" is located between the Iksa and Bakchar rivers (56o58`N 82o36`E) at the Bakcharskoe bog (area 1400 km2). The key area "Ob'-Tom'"is located in the northern part of Ob' and Tom' interfluve (56o21`N 82o31`E). The "Bakchar" key area includes the following ecosystems: pine- shrub-sphagnum community, a similar community with stunted (low) pine trees, and sedge-sphagnum fen. Two small peatlands were studied at Ob' and Tom' interfluve. Kirsanovskoe bog includes pine- shrub-sphagnum community and sedge fen. Timiryazevskoe bog was represented by pine- shrub-sphagnum (TPSS) community and sedge fen. An infrared gas analyzer OPTOGAS 500.4 (OPTEC Corp., St.-Petersburg, Russia) attached to a static opaque plastic been used for carbon dioxide emission measurements. The net primary productivity was measured by clipping method (Golovatskaya and Dyukarev, Plant Soil 2009). Peatlands at "Ob'-Tom'" key area

  4. Minor effects of long-term ozone exposure on boreal peatland species Eriophorum vaginatum and Sphagnum papillosum

    DEFF Research Database (Denmark)

    Mörsky, SK; Haapala, JK; Rinnan, Riikka

    2011-01-01

    The effects of long-term ozone fumigation on two common peatland plant species, a sedge Eriophorum vaginatum L. and a moss Sphagnum papillosum Lindb., were studied applying peatland microcosms. The peat cores with intact vegetation were cored from an oligotrophic pine fen and partially embedded...

  5. Oligotrophic bacteria isolated from clinical materials.

    OpenAIRE

    Tada, Y; Ihmori, M; Yamaguchi, J

    1995-01-01

    Oligotrophic bacteria (oligotrophs) are microorganisms that grow in extremely nutritionally deficient conditions in which the concentrations of organic substances are low. Many oligotrophic bacteria were isolated from clinical materials including urine, sputum, swabbings of the throat, vaginal discharges, and others. Seventy-seven strains of oligotrophic bacteria from 871 samples of clinical material were isolated. A relatively higher frequency of isolation of oligotrophic bacteria was shown ...

  6. Phylogenetic comparison of the methanogenic communities from an acidic, oligotrophic fen and an anaerobic digester treating municipal wastewater sludge.

    Science.gov (United States)

    Steinberg, Lisa M; Regan, John M

    2008-11-01

    Methanogens play a critical role in the decomposition of organics under anaerobic conditions. The methanogenic consortia in saturated wetland soils are often subjected to large temperature fluctuations and acidic conditions, imposing a selective pressure for psychro- and acidotolerant community members; however, methanogenic communities in engineered digesters are frequently maintained within a narrow range of mesophilic and circumneutral conditions to retain system stability. To investigate the hypothesis that these two disparate environments have distinct methanogenic communities, the methanogens in an oligotrophic acidic fen and a mesophilic anaerobic digester treating municipal wastewater sludge were characterized by creating clone libraries for the 16S rRNA and methyl coenzyme M reductase alpha subunit (mcrA) genes. A quantitative framework was developed to assess the differences between these two communities by calculating the average sequence similarity for 16S rRNA genes and mcrA within a genus and family using sequences of isolated and characterized methanogens within the approved methanogen taxonomy. The average sequence similarities for 16S rRNA genes within a genus and family were 96.0 and 93.5%, respectively, and the average sequence similarities for mcrA within a genus and family were 88.9 and 79%, respectively. The clone libraries of the bog and digester environments showed no overlap at the species level and almost no overlap at the family level. Both libraries were dominated by clones related to uncultured methanogen groups within the Methanomicrobiales, although members of the Methanosarcinales and Methanobacteriales were also found in both libraries. Diversity indices for the 16S rRNA gene library of the bog and both mcrA libraries were similar, but these indices indicated much lower diversity in the 16S digester library than in the other three libraries.

  7. BOREAS TF-10 NSA-Fen Tower Flux and Meteorological Data

    Science.gov (United States)

    McCaughey, J. Harry; Hall, Forrest G. (Editor); Huemmrich, Karl (Editor); Jelinski, Dennis E.

    2000-01-01

    The BOREAS TF-10 team collected tower flux and meteorological data at two sites, a fen and a young jack pine forest, near Thompson, Manitoba, Canada, as part of BOREAS. A preliminary data set was assembled in August 1993 while field testing the instrument packages, and at both sites data were collected from 15-Aug to 31-Aug. The main experimental period was in 1994, when continuous data were collected from 08-Apr to 23-Sep at the fen site. A very limited experiment was run in the spring/ summer of 1995, when the fen site tower was operated from 08-Apr to 14-Jun in support of a hydrology experiment in an adjoining feeder basin. Upon examination of the 1994 data set, it became clear that the behavior of the heat, water, and carbon dioxide fluxes throughout the whole growing season was an important scientific question, and that the 1994 data record was not sufficiently long to capture the character of the seasonal behavior of the fluxes. Thus, the fen site was operated in 1996 in order to collect data from spring melt to autumn freeze-up. Data were collected from 29-Apr to 05-Nov at the fen site. All variables are presented as 30-minute averages. The data are stored in tabular ASCII files.

  8. Prospects for fen meadow restoration on severely degraded fens

    NARCIS (Netherlands)

    Klimkowska, Agata; Diggelen, Rudy Van; Grootjans, Ab P.; Kotowski, Wiktor

    2010-01-01

    The majority of fens in Europe have been transformed for agricultural purposes and have disappeared or become degraded. Fen meadows that developed under low-intensity management of fens also have become degraded. In this paper, we consider the available restoration methods, biotic constraints for

  9. BOREAS TGB-6 Soil Methane Oxidation and Production from NSA BP and Fen Sites

    Science.gov (United States)

    Deck, Bruce; Wahlen, Martin; Hall, Forrest G. (Editor); Conrad, Sara K. (Editor)

    2000-01-01

    The BOReal Ecosystem-Atmosphere Study Trace Gas Biogeochemistry (BOREAS TGB-6) team collected soil methane measurements at several sites in the Southern Study Area (SSA) and Northern Study Area (NSA). This data set contains soil methane consumption (bacterial CH4 oxidation) and associated C-13 fractionation effects in samples that were collected at various sites in 1994 and 1996 from enclosures (chambers). Methane C-13 data in soil gas samples from the NSA Young Jack Pine (YJP) and Old Jack Pine (OJP) sites for 1994 and 1996 are also given. Additional data on the isotopic composition of methane (carbon and hydrogen isotopes) produced in the NSA beaver ponds and fen bog in 1993 and 1994 are given as well. The data are stored in tabular ASCII files.

  10. N and P addition inhibits growth of rich fen bryophytes

    DEFF Research Database (Denmark)

    Andersen, Dagmar Kappel; Ejrnæs, Rasmus; Riis, Tenna

    2016-01-01

    vernicosus and paludella squarrosa) rich fen bryophytes were grown in mixed culture and subjected to rainwater or groundwater and three levels of N (0, 1 and 3 mg N L-1) and P (0, 0.05 and 0.1 mg P NL-1). All species responded negatively to higher N-levels and three of four species responded negatively...... to rainwater and higher P-levels. C. cuspidata had highest relative growth rate in all treatments, and the infrequently occurringrare species had lower relative growth rate and were more negatively affected by high levels of N than the frequently occurringcommon species. A negative effect of rainwater seemed...... to be caused by higher background levels of N in rainwater compared to groundwater rather than a pH-effect per se. We found a negative effect of high initial bryophyte density in three of four species indicating density dependent inhibition between species.We suggest that maintenance of oligotrophic conditions...

  11. Seed dispersal in fens

    NARCIS (Netherlands)

    Middleton, Beth; van Diggelen, Rudy; Jensen, Kai

    Question: How does seed dispersal reduce fen isolation and contribute to biodiversity? Location: European and North American fens. Methods: This paper reviews the literature on seed dispersal to fens. Results: Landscape fragmentation may reduce dispersal opportunities thereby isolating fens and

  12. Seed dispersal in fens

    Science.gov (United States)

    Middleton, B.; Van Diggelen, R.; Jensen, K.

    2006-01-01

    Question: How does seed dispersal reduce fen isolation and contribute to biodiversity? Location: European and North American fens. Methods: This paper reviews the literature on seed dispersal to fens. Results: Landscape fragmentation may reduce dispersal opportunities thereby isolating fens and reducing genetic exchange. Species in fragmented wetlands may have lower reproductive success, which can lead to biodiversity loss. While fens may have always been relatively isolated from each other, they have become increasingly fragmented in modern times within agricultural and urban landscapes in both Europe and North America. Dispersal by water, animals and wind has been hampered by changes related to development in landscapes surrounding fens. Because the seeds of certain species are long-lived in the seed bank, frequent episodes of dispersal are not always necessary to maintain the biodiversity of fens. However, of particular concern to restoration is that some dominant species, such as the tussock sedge Carex stricta, may not disperse readily between fens. Conclusions: Knowledge of seed dispersal can be used to maintain and restore the biodiversity of fens in fragmented landscapes. Given that development has fragmented landscapes and that this situation is not likely to change, the dispersal of seeds might be enhanced by moving hay or cattle from fens to damaged sites, or by reestablishing lost hydrological connections. ?? IAVS; Opulus Press.

  13. Oligotrophication and Metabolic Slowing-Down of a NW Mediterranean Coastal Ecosystem

    Directory of Open Access Journals (Sweden)

    Susana Agusti

    2017-12-01

    Full Text Available Increased oligotrophication is expected for oligotrophic areas as a consequence of ocean warming, which reduces diffusive vertical nutrient supply due to strengthened stratification. Evidence of ocean oligotrophication has been, thus far, reported for the open ocean. Here we reported oligotrophication and associated changes in plankton community metabolism with warming in a pristine, oligotrophic Mediterranean coastal area (Cap Salines, Mallorca Island, Spain during a 10 years time series. As a temperate area, there were seasonal patterns associated to changes in the broad temperature range (12.0–28.4°C, with a primary phytoplankton bloom in late winter and a secondary one in the fall. Community respiration (R rates peaked during summers and showed higher rates relative to gross primary production (GPP with a prevalence of heterotrophic metabolism (2/3's of net community production (NCP estimates. Chlorophyll a concentration significantly decreased with increasing water temperature in the coastal site at a rate of 0.014 ± 0.003 μg Chla L−1 °C−1 (P < 0.0001. The study revealed a significant decrease with time in Chlorophyll a concentration and nutrients concentration, indicating oligotrophication during the last decade. Community productivity consistently decreased with time as both GPP and R showed a significant decline. Warming of the Mediterranean Sea is expected to increase plankton metabolic rates, but the results indicated that the associated oligotrophication must lead to a slowing down of the community metabolism.

  14. Oligotrophication and Metabolic Slowing-Down of a NW Mediterranean Coastal Ecosystem

    KAUST Repository

    Agusti, Susana

    2017-12-22

    Increased oligotrophication is expected for oligotrophic areas as a consequence of ocean warming, which reduces diffusive vertical nutrient supply due to strengthened stratification. Evidence of ocean oligotrophication has been, thus far, reported for the open ocean. Here we reported oligotrophication and associated changes in plankton community metabolism with warming in a pristine, oligotrophic Mediterranean coastal area (Cap Salines, Mallorca Island, Spain) during a 10 years time series. As a temperate area, there were seasonal patterns associated to changes in the broad temperature range (12.0–28.4°C), with a primary phytoplankton bloom in late winter and a secondary one in the fall. Community respiration (R) rates peaked during summers and showed higher rates relative to gross primary production (GPP) with a prevalence of heterotrophic metabolism (2/3\\'s of net community production (NCP) estimates). Chlorophyll a concentration significantly decreased with increasing water temperature in the coastal site at a rate of 0.014 ± 0.003 μg Chla L−1 °C−1 (P < 0.0001). The study revealed a significant decrease with time in Chlorophyll a concentration and nutrients concentration, indicating oligotrophication during the last decade. Community productivity consistently decreased with time as both GPP and R showed a significant decline. Warming of the Mediterranean Sea is expected to increase plankton metabolic rates, but the results indicated that the associated oligotrophication must lead to a slowing down of the community metabolism.

  15. Hydrological landscape settings of base-rich fen mires and fen meadows : an overview

    NARCIS (Netherlands)

    Grootjans, A.P.; Adema, E.B.; Bleuten, W.; Joosten, H.; Madaras, M.; Janáková, M.; Middleton, B.

    2006-01-01

    Question: Why do similar fen meadow communities occur in different landscapes? How does the hydrological system sustain base-rich fen mires and fen meadows? Location: Interdunal wetlands and heathland pools in The Netherlands, percolation mires in Germany, Poland, and Siberia, and calcareous spring

  16. Geochemistry and hydrology of a calcareous fen within the Savage Fen wetlands complex, Minnesota, USA

    Science.gov (United States)

    Komor, S.C.

    1994-01-01

    Savage Fen is a wetlands complex at the base of north-facing bluffs in the Minnesota River Valley. The complex includes 27.8 hectares of calcareous fen that host rare calciphile plants whose populations are declining in Minnesota. Water and sediment compositions in the calcareous fen were studied to gain a better understanding of the hydrologie System that sustains the rare vegetation. Groundwater in the fen is a calcium-magnesium-bicarbonate type with circumneutral pH values. The groundwater composition is the resuit of interactions among water, dissolved and gaseous carbon species, carbonates, and ion exchangers. Shallow groundwater is distinguished from deep groundwater by smaller concentrations of chloride, sulfate, magnesium, and sodium, and larger concentrations of calcium, bicarbonate, hydrogen sulfide, and ammonium. Magnesian calcite is the prevalent carbonate in unconsolidated sedimentary fill beneath the fen and is an important source and sink for dissolved calcium, magnesium, and inorganic carbon. Calcite concentrations just below the water table are small because aerobic and anaerobic oxidation of organic matter increase the partial pressure of carbon dioxide (PCO2), decrease pH, and cause calcite to dissolve. Thick calcite accumulations just above the water table, in the root zone of calciphile plants, result from water table fluctuations and attendant changes in PCO2. Groundwater beneath Savage Fen recharges in lakes and ponds south of the fen and upwells to the surface within the fen. Water at the water table is a mixture of upwelling groundwater and water near the surface that flows downslope from higher elevations in the fen. Changes in oxygen and hydrogen isotope compositions of shallow groundwater indicate that the proportion of upwelling groundwater in shallow groundwater decreases downgradient in the calcareous fen. Encroachment of reed grasses into the calcareous fen may reflect human-caused disturbances in the recharge area.

  17. Picocyanobacteria success in oligotrophic lakes: fact or fiction?

    Directory of Open Access Journals (Sweden)

    Cristiana CALLIERI

    2000-02-01

    Full Text Available Two approaches may be utilized to explain the predominance of picocyanobacteria (Pcy in oligotrophic lakes: the analysis of their interannual evolution in one single lake and their relative importance in different lakes along a trophic gradient. Here we discuss results from field data on picocyanobacteria over several seasons from a deep oligotrophic subalpine lake - Lago Maggiore, and variables influencing their abundance. Comparing data from lakes along a trophic gradient, no simple relationship emerges between lake’s trophic state and picocyanobacteria abundance and contribution to total phytoplanktonic biomass. That is, trophic state alone cannot explain the success/absence of picocyanobacteria that appear to be favored under P limitation, but seem more sensitive to grazing pressure and light. In some oligotrophic lakes, if light climate, grazing, and competition are favorable, picocyanobacteria can grow rapidly, out-compete competitors and become very abundant, but there are a host of factors that can influence the outcome of this competition, and ultimately influence Pcy success in lakes of all trophic types.

  18. The paradox of algal blooms in oligotrophic waters

    Science.gov (United States)

    Sundareshwar, P. V.; Upadhyay, S.; Abessa, M. B.; Honomichl, S.; Berdanier, B.; Spaulding, S.; Sandvik, C.; Trennepohl, A.

    2010-12-01

    Nutrient inputs to streams and lakes, primarily from anthropogenic sources, lead to eutrophic conditions that favor algal blooms with undesirable consequences. In contrast, low nutrient or oligotrophic waters rarely support algal blooms; such ecosystems are typically lower in productivity. Since the mid-1980’s however, the diatom Didymosphenia geminata has dramatically expanded its range colonizing oligotrophic rivers worldwide with blooms appearing as thick benthic mats. This recent global occurrence of Didymosphenia geminata blooms in temperate rivers has been perplexing in its pace of spread and the paradoxical nature of the nuisance growths. The blooms occur primarily in oligotrophic flowing waters, where phosphorus (P) availability often limits primary production. We present a biogeochemical process by which D. geminata mats adsorb both P and iron (Fe) from flowing waters and make P available for cellular uptake. The adsorbed P becomes bioavailable through biogeochemical processes that occur within the mat. The biogeochemical processes observed here while well accepted in benthic systems are novel for algal blooms in lotic habits. Enzymatic and bacterial processes such as Fe and sulfate reduction can release the adsorbed P and increase its bioavailability, creating a positive feedback between total stalk biomass and nutrient availability. Stalk affinity for Fe, Fe-P biogeochemistry, and interaction between watershed processes and climatic setting explain the paradoxical blooms, and the recent global spread of this invasive aquatic species. At a broader scale the study also implies that such algal blooms in oligotrophic environments can fundamentally alter the retention and longitudinal transfer of important nutrients such as P in streams and rivers.

  19. Evaluating stocking efficacy in an ecosystem undergoing oligotrophication

    Science.gov (United States)

    Kao, Yu-Chun; Rogers, Mark W.; Bunnell, David B.

    2017-01-01

    Oligotrophication has negatively affected fisheries production in many freshwater ecosystems and could conceivably reduce the efficacy of stockings used to enhance fisheries. In Lake Michigan, offshore oligotrophication has occurred since the 1970s, owing to reductions in total phosphorus (TP) inputs and nearshore sequestration of TP by nonindigenous dreissenid mussels. We evaluated simultaneous effects of stock enhancement and oligotrophication on salmonine species (Chinook salmon Oncorhynchus tshawytscha, lake trout Salvelinus namaycush, and steelhead O. mykiss) that support valuable recreational fisheries. We employed a novel application of an Ecopath with Ecosim model by conducting a full factorial simulation experiment. Our design included multiple levels of salmonine stocking, consumption by invasive quagga mussels (Dreissena bugensis), and TP that were informed by manager interests. Under all levels of TP and quagga mussel consumption, our results showed that stock enhancement could still increase salmonine biomass, but positive responses were stronger for lake trout and steelhead than Chinook salmon. Simulations showed that quagga mussel consumption has deleterious effects on pelagic-oriented prey fishes and Chinook salmon, which feed almost exclusively on the pelagic-oriented alewife (Alosa pseudoharengus). In summary, results from our simulation experiment suggested that lake trout and steelhead are better suited to the current ecosystem than Chinook salmon, and therefore, stock enhancement provides the highest gains for these two species. Furthermore, simulated biomass of all recreational salmonine species increased with increasing TP, indicating the need for managers to consider how potential future oligotrophication will limit the carrying capacity of salmonine biomass in Lake Michigan

  20. Warm summer nights and the growth decline of shore pine in Southeast Alaska

    Science.gov (United States)

    Sullivan, Patrick F.; Mulvey, Robin L.; Brownlee, Annalis H.; Barrett, Tara M.; Pattison, Robert R.

    2015-12-01

    Shore pine, which is a subspecies of lodgepole pine, was a widespread and dominant tree species in Southeast Alaska during the early Holocene. At present, the distribution of shore pine in Alaska is restricted to coastal bogs and fens, likely by competition with Sitka spruce and Western hemlock. Monitoring of permanent plots as part of the United States Forest Service Forest Inventory and Analysis program identified a recent loss of shore pine biomass in Southeast Alaska. The apparent loss of shore pine is concerning, because its presence adds a vertical dimension to coastal wetlands, which are the richest plant communities of the coastal temperate rainforest in Alaska. In this study, we examined the shore pine tree-ring record from a newly established plot network throughout Southeast Alaska and explored climate-growth relationships. We found a steep decline in shore pine growth from the early 1960s to the present. Random Forest regression revealed a strong correlation between the decline in shore pine growth and the rise in growing season diurnal minimum air temperature. Warm summer nights, cool daytime temperatures and a reduced diurnal temperature range are associated with greater cloud cover in Southeast Alaska. This suite of conditions could lead to unfavorable tree carbon budgets (reduced daytime photosynthesis and greater nighttime respiration) and/or favor infection by foliar pathogens, such as Dothistroma needle blight, which has recently caused widespread tree mortality on lodgepole pine plantations in British Columbia. Further field study that includes experimental manipulation (e.g., fungicide application) will be necessary to identify the proximal cause(s) of the growth decline. In the meantime, we anticipate continuation of the shore pine growth decline in Southeast Alaska.

  1. Plant biomass carbon store after water-level drawdown of pine mires

    Energy Technology Data Exchange (ETDEWEB)

    Laiho, R; Laine, J [Helsinki Univ. (Finland). Dept. of Ecology

    1997-12-31

    Tall-sedge pine fen is the site type most commonly drained in Finland. In their natural undrained condition sites of this type are rather wet with sparse, Scots pine dominated forest growing on hummocks and with large lawns dominated by sedges, usually Carex rostrata and/or C. lasiocarpa. Most of the primary production takes place in the field and ground layers. The major pathway for carbon accumulation in the system is via Sphagna and sedge roots, carbon accumulation by the tree stand being very slow. After drainage the situation changes radically as the sedges die out and the tree stand growth increases considerably. The aim of this study is to produce means of estimating the post-drainage dynamics of the plant biomass carbon store. The study is based on the assumption that sites similar before drainage will change in a similar manner following drainage. (5 refs.)

  2. Plant biomass carbon store after water-level drawdown of pine mires

    Energy Technology Data Exchange (ETDEWEB)

    Laiho, R.; Laine, J. [Helsinki Univ. (Finland). Dept. of Ecology

    1996-12-31

    Tall-sedge pine fen is the site type most commonly drained in Finland. In their natural undrained condition sites of this type are rather wet with sparse, Scots pine dominated forest growing on hummocks and with large lawns dominated by sedges, usually Carex rostrata and/or C. lasiocarpa. Most of the primary production takes place in the field and ground layers. The major pathway for carbon accumulation in the system is via Sphagna and sedge roots, carbon accumulation by the tree stand being very slow. After drainage the situation changes radically as the sedges die out and the tree stand growth increases considerably. The aim of this study is to produce means of estimating the post-drainage dynamics of the plant biomass carbon store. The study is based on the assumption that sites similar before drainage will change in a similar manner following drainage. (5 refs.)

  3. On the non-closure of particle backscattering coefficient in oligotrophic oceans.

    Science.gov (United States)

    Lee, ZhongPing; Huot, Yannick

    2014-11-17

    Many studies have consistently found that the particle backscattering coefficient (bbp) in oligotrophic oceans estimated from remote-sensing reflectance (Rrs) using semi-analytical algorithms is higher than that from in situ measurements. This overestimation can be as high as ~300% for some oligotrophic ocean regions. Various sources potentially responsible for this discrepancy are examined. Further, after applying an empirical algorithm to correct the impact from Raman scattering, it is found that bbp from analytical inversion of Rrs is in good agreement with that from in situ measurements, and that a closure is achieved.

  4. Unravelling hydrological mechanisms behind fen deterioration

    NARCIS (Netherlands)

    van Loon, A.H.

    2010-01-01

    Low-productive fens are wetland ecosystems that have strongly declined in number and size in temperate regions of Western Europe since World War II. This fen type has significant conservation value in many countries because of its high species diversity and the presence of endangered plant species.

  5. Incidental oligotrophication of North American Great Lakes.

    Science.gov (United States)

    Evans, Mary Anne; Fahnenstiel, Gary; Scavia, Donald

    2011-04-15

    Phytoplankton production is an important factor in determining both ecosystem stability and the provision of ecosystem goods and services. The expansive and economically important North American Great Lakes are subjected to multiple stressors and understanding their responses to those stresses is important for understanding system-wide ecological controls. Here we show gradual increases in spring silica concentration (an indicator of decreasing growth of the dominant diatoms) in all basins of Lakes Michigan and Huron (USA and Canadian waters) between 1983 and 2008. These changes indicate the lakes have undergone gradual oligotrophication coincident with and anticipated by nutrient management implementation. Slow declines in seasonal drawdown of silica (proxy for seasonal phytoplankton production) also occurred, until recent years, when lake-wide responses were punctuated by abrupt decreases, putting them in the range of oligotrophic Lake Superior. The timing of these dramatic production drops is coincident with expansion of populations of invasive dreissenid mussels, particularly quagga mussels, in each basin. The combined effect of nutrient mitigation and invasive species expansion demonstrates the challenges facing large-scale ecosystems and suggest the need for new management regimes for large ecosystems.

  6. Experimental restoration of a fen plant community after peat mining

    Energy Technology Data Exchange (ETDEWEB)

    Cobbaert, D.; Rochefort, L.; Price, J.S. [Univ. Laval, Sainte-Foy (Canada). Dept. de Phytologie

    2004-11-01

    Methods: The effectiveness of introducing fen plants with the application of donor diaspore material was tested. The donor diaspore material, containing seeds, rhizomes, moss fragments, and other plant propagules, was collected from two different types of natural fens. We tested whether the application of straw mulch would increase fen species cover and biodiversity compared to control plots without straw mulch. Terrace levels of different peat depths (15 cm, 40 cm, and 56 cm) were created to test the effects of different environmental site conditions on the success of re-vegetation. Results: Applying donor seed bank from natural fens was found to significantly increase fen plant cover and richness after the two growing seasons. Straw mulch proved to significantly increase fen plant richness. The intermediate terrace level (40 cm) had the highest fen plant establishment. Compared to reference sites, the low terrace level (15 cm) was richer in base cations, whereas the high terrace level (56 cm) was much drier. Conclusions: The application of donor diaspore material was demonstrated as an effective technique for establishing vascular fen plants. Further rewetting measures are considered necessary at the restoration site to create a fen ecosystem rather than simply restoring some fen species (Location: Riviere-du-Loup peatland, southern Quebec, Canada at 100 m a.s.l.)

  7. High resistance of some oligotrophic bacteria to ionizing radiation

    International Nuclear Information System (INIS)

    Nikitin, D.I.; Tashtemirova, M.A.; Pitryuk, I.A.; Sorokin, V.V.; Oranskaya, M.S.; Nikitin, L.E.

    1994-01-01

    The resistance of seven cultures of eutrophic and oligotrophic bacteria to gamma radiation (at doses up to 360 Gy) was investigated. The bacteria under study were divided into three groups according to their survival ability after irradiation. Methylobacterium organophilum and open-quotes Pedodermatophilus halotoleransclose quotes (LD 50 = 270 Gy) were highly tolerant. By their tolerance, these organisms approached Deinococcus radiodurans. Aquatic ring-shaped (toroidal) bacteria Flectobacillus major and open-quotes Arcocella aquaticaclose quotes (LD 5 = 173 and 210 Gy, respectively) were moderately tolerant. Eutrophic Pseudomonas fluorescens and Escherichia coli (LD 50 = 43 and 38 Gy, respectively) were the most sensitive. X-ray microanalysis showed that in tolerant bacteria the intracellular content of potassium increased and the content of calcium decreased after irradiation. No changes in the element composition of the eutrophic bacterium E. coli were detected. Possible mechanisms of the resistance of oligotrophic bacteria to gamma radiation are discussed

  8. Fens As Ecohydrologic Gauges of Climate Change in California

    Science.gov (United States)

    Drexler, J. Z.; Flint, L. E.; Flint, A. L.; Knifong, D. L.

    2014-12-01

    The purpose of this study was to demonstrate the use of montane groundwater-fed peatlands called fens as gauges for changes in groundwater recharge through time. Due to their consistent groundwater flows, fens remain saturated during the growing season, thus serving as ecological refugia for a range of sensitive biota including the federally threatened Yosemite toad (Anaxyrus canorus). In this project, five fens in the Sierra Nevada and two in the southern Cascade Mountains were studied over a 50-80 year period using historic aerial photography and GIS analysis. Fen areas were delineated using vegetation distributions and site wetness as visual keys to fen areal extent. In addition, a climate analysis of precipitation, snowpack, evapotranspiration, and mean minimum monthly temperature (Tmin) was carried out for the years 1950 - 2010 using a distributed parameter water-balance model called the Basin Characterization Model. Over the study period, all five Sierra fens decreased by 10-15% in delineated area, but little change occurred in the Cascade fens. The climate analysis revealed major changes through time in Tmin and the frequency of June months with zero snowpack (snowpack longevity) at the five Sierra sites. At the Cascade sites, increases in Tmin occurred more recently and decreases in snowpack longevity were more subtle. The different behavior of fens in the Cascades versus the Sierra Nevada suggests that underlying geology, particularly hydraulic conductivity, rock porosity, and size of groundwater reservoirs, may be an important buffer to change. These results show that fens in the Sierra Nevada are highly responsive ecohydrologic gauges that can be used to track reductions in groundwater recharge due to climate change. Further studies using isotopic and/or geochemical approaches are needed to quantify the changes in groundwater recharge that were identified with fens. Because fens provide critical habitat for sensitive species, major changes in hydrology

  9. Interaction between APC and Fen1 during breast carcinogenesis.

    Science.gov (United States)

    Narayan, Satya; Jaiswal, Aruna S; Law, Brian K; Kamal, Mohammad A; Sharma, Arun K; Hromas, Robert A

    2016-05-01

    Aberrant DNA base excision repair (BER) contributes to malignant transformation. However, inter-individual variations in DNA repair capacity plays a key role in modifying breast cancer risk. We review here emerging evidence that two proteins involved in BER - adenomatous polyposis coli (APC) and flap endonuclease 1 (Fen1) - promote the development of breast cancer through novel mechanisms. APC and Fen1 expression and interaction is increased in breast tumors versus normal cells, APC interacts with and blocks Fen1 activity in Pol-β-directed LP-BER, and abrogation of LP-BER is linked with cigarette smoke condensate-induced transformation of normal breast epithelial cells. Carcinogens increase expression of APC and Fen1 in spontaneously immortalized human breast epithelial cells, human colon cancer cells, and mouse embryonic fibroblasts. Since APC and Fen1 are tumor suppressors, an increase in their levels could protect against carcinogenesis; however, this does not seem to be the case. Elevated Fen1 levels in breast and lung cancer cells may reflect the enhanced proliferation of cancer cells or increased DNA damage in cancer cells compared to normal cells. Inactivation of the tumor suppressor functions of APC and Fen1 is due to their interaction, which may act as a susceptibility factor for breast cancer. The increased interaction of APC and Fen1 may occur due to polypmorphic and/or mutational variation in these genes. Screening of APC and Fen1 polymorphic and/or mutational variations and APC/Fen1 interaction may permit assessment of individual DNA repair capability and the risk for breast cancer development. Such individuals might lower their breast cancer risk by reducing exposure to carcinogens. Stratifying individuals according to susceptibility would greatly assist epidemiologic studies of the impact of suspected environmental carcinogens. Additionally, a mechanistic understanding of the interaction of APC and Fen1 may provide the basis for developing new and

  10. Causes of change in nitrophytic and oligotrophic lichen species in a Mediterranean climate: Impact of land cover and atmospheric pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Pinho, P.; Augusto, S.; Martins-Loucao, M.A. [Faculdade de Ciencias, Centro de Ecologia e Biologia Vegetal, Universidade de Lisboa, edificio C4, 1749-016 Lisbon (Portugal); Pereira, M.J.; Soares, A. [Instituto Superior Tecnico, Universidade Tecnica de Lisboa, Cerena, Av. Rovisco Pais, 1049-001 Lisbon (Portugal); Maguas, C. [Faculdade de Ciencias, Centro de Ecologia e Biologia Vegetal, Universidade de Lisboa, edificio C4, 1749-016 Lisbon (Portugal); Branquinho, C. [Faculdade de Ciencias, Centro de Ecologia e Biologia Vegetal, Universidade de Lisboa, edificio C4, 1749-016 Lisbon (Portugal); Antiga Fabrica da Polvora de Barcarena, Universidade Atlantica, 2745-615 Barcarena (Portugal)], E-mail: cmbranquinho@fc.ul.pt

    2008-08-15

    With the aim of determining the main drivers of changes in nitrophytic and oligotrophic macro-lichen communities in an industrial region with a Mediterranean climate, we considered both land-cover types and atmospheric pollutants. We determined the relation between the abundance of nitrophytic and oligotrophic species with environmental factors considering the distance of influence of land-cover types. The results showed that oligotrophic species decreased in the proximity of artificial areas, barren land and agricultural areas, associated with higher concentrations of NO{sub 2} and Zn, and Ti, probably dust of industrial and agricultural origin. Nitrophytic species were positively related to all the mentioned land-cover types, and with higher concentrations of Fe and N. Magnesium, probably from ocean aerosols, was negatively related to oligotrophic species and positively to nitrophytic. - Causes of change in nitrophytic and oligotrophic lichen species.

  11. Causes of change in nitrophytic and oligotrophic lichen species in a Mediterranean climate: Impact of land cover and atmospheric pollutants

    International Nuclear Information System (INIS)

    Pinho, P.; Augusto, S.; Martins-Loucao, M.A.; Pereira, M.J.; Soares, A.; Maguas, C.; Branquinho, C.

    2008-01-01

    With the aim of determining the main drivers of changes in nitrophytic and oligotrophic macro-lichen communities in an industrial region with a Mediterranean climate, we considered both land-cover types and atmospheric pollutants. We determined the relation between the abundance of nitrophytic and oligotrophic species with environmental factors considering the distance of influence of land-cover types. The results showed that oligotrophic species decreased in the proximity of artificial areas, barren land and agricultural areas, associated with higher concentrations of NO 2 and Zn, and Ti, probably dust of industrial and agricultural origin. Nitrophytic species were positively related to all the mentioned land-cover types, and with higher concentrations of Fe and N. Magnesium, probably from ocean aerosols, was negatively related to oligotrophic species and positively to nitrophytic. - Causes of change in nitrophytic and oligotrophic lichen species

  12. Effect of Groundwater Abstraction on Fen Ecosystems

    DEFF Research Database (Denmark)

    Johansen, Ole; Pedersen, Morten Lauge; Jensen, Jacob Birk

    2011-01-01

    within a distance of 1.5 km to a planned well field. In the river valley the interaction between groundwater and surface water is strongly affected by low permeable sediments. These sediments reduce the direct discharge to the river and have a large impact on the functioning and presence of the rich fen......Quantifying the effects of groundwater abstraction on fen ecosystems located in discharge areas can be complicated. The water level in fens is close to the terrain surface most of the year and it is controlled by a relatively constant groundwater exfiltration. It is difficult to measure...... the exfiltration fluxes and thus water level data is typically used to evaluate if the ecosystem is affected. The paper presents collected data and analysis from a case study, where the hydrological effect of groundwater abstraction on rich fens and springs in a Danish river valley has been studied. The natural...

  13. Plankton networks driving carbon export in the oligotrophic ocean

    Science.gov (United States)

    Larhlimi, Abdelhalim; Roux, Simon; Darzi, Youssef; Audic, Stephane; Berline, Léo; Brum, Jennifer; Coelho, Luis Pedro; Espinoza, Julio Cesar Ignacio; Malviya, Shruti; Sunagawa, Shinichi; Dimier, Céline; Kandels-Lewis, Stefanie; Picheral, Marc; Poulain, Julie; Searson, Sarah; Stemmann, Lars; Not, Fabrice; Hingamp, Pascal; Speich, Sabrina; Follows, Mick; Karp-Boss, Lee; Boss, Emmanuel; Ogata, Hiroyuki; Pesant, Stephane; Weissenbach, Jean; Wincker, Patrick; Acinas, Silvia G.; Bork, Peer; de Vargas, Colomban; Iudicone, Daniele; Sullivan, Matthew B.; Raes, Jeroen; Karsenti, Eric; Bowler, Chris; Gorsky, Gabriel

    2015-01-01

    The biological carbon pump is the process by which CO2 is transformed to organic carbon via photosynthesis, exported through sinking particles, and finally sequestered in the deep ocean. While the intensity of the pump correlates with plankton community composition, the underlying ecosystem structure driving the process remains largely uncharacterised. Here we use environmental and metagenomic data gathered during the Tara Oceans expedition to improve our understanding of carbon export in the oligotrophic ocean. We show that specific plankton communities, from the surface and deep chlorophyll maximum, correlate with carbon export at 150 m and highlight unexpected taxa such as Radiolaria, alveolate parasites, as well as Synechococcus and their phages, as lineages most strongly associated with carbon export in the subtropical, nutrient-depleted, oligotrophic ocean. Additionally, we show that the relative abundance of just a few bacterial and viral genes can predict most of the variability in carbon export in these regions. PMID:26863193

  14. Plankton networks driving carbon export in the oligotrophic ocean

    Science.gov (United States)

    2016-04-01

    The biological carbon pump is the process by which CO2 is transformed to organic carbon via photosynthesis, exported through sinking particles, and finally sequestered in the deep ocean. While the intensity of the pump correlates with plankton community composition, the underlying ecosystem structure driving the process remains largely uncharacterized. Here we use environmental and metagenomic data gathered during the Tara Oceans expedition to improve our understanding of carbon export in the oligotrophic ocean. We show that specific plankton communities, from the surface and deep chlorophyll maximum, correlate with carbon export at 150 m and highlight unexpected taxa such as Radiolaria and alveolate parasites, as well as Synechococcus and their phages, as lineages most strongly associated with carbon export in the subtropical, nutrient-depleted, oligotrophic ocean. Additionally, we show that the relative abundance of a few bacterial and viral genes can predict a significant fraction of the variability in carbon export in these regions.

  15. Whitebark pine mortality related to white pine blister rust, mountain pine beetle outbreak, and water availability

    Science.gov (United States)

    Shanahan, Erin; Irvine, Kathryn M.; Thoma, David P.; Wilmoth, Siri K.; Ray, Andrew; Legg, Kristin; Shovic, Henry

    2016-01-01

    Whitebark pine (Pinus albicaulis) forests in the western United States have been adversely affected by an exotic pathogen (Cronartium ribicola, causal agent of white pine blister rust), insect outbreaks (Dendroctonus ponderosae, mountain pine beetle), and drought. We monitored individual trees from 2004 to 2013 and characterized stand-level biophysical conditions through a mountain pine beetle epidemic in the Greater Yellowstone Ecosystem. Specifically, we investigated associations between tree-level variables (duration and location of white pine blister rust infection, presence of mountain pine beetle, tree size, and potential interactions) with observations of individual whitebark pine tree mortality. Climate summaries indicated that cumulative growing degree days in years 2006–2008 likely contributed to a regionwide outbreak of mountain pine beetle prior to the observed peak in whitebark mortality in 2009. We show that larger whitebark pine trees were preferentially attacked and killed by mountain pine beetle and resulted in a regionwide shift to smaller size class trees. In addition, we found evidence that smaller size class trees with white pine blister rust infection experienced higher mortality than larger trees. This latter finding suggests that in the coming decades white pine blister rust may become the most probable cause of whitebark pine mortality. Our findings offered no evidence of an interactive effect of mountain pine beetle and white pine blister rust infection on whitebark pine mortality in the Greater Yellowstone Ecosystem. Interestingly, the probability of mortality was lower for larger trees attacked by mountain pine beetle in stands with higher evapotranspiration. Because evapotranspiration varies with climate and topoedaphic conditions across the region, we discuss the potential to use this improved understanding of biophysical influences on mortality to identify microrefugia that might contribute to successful whitebark pine conservation

  16. Mountain Pine Beetle Fecundity and Offspring Size Differ Among Lodgepole Pine and Whitebark Pine Hosts

    OpenAIRE

    Gross, Donovan

    2008-01-01

    Whitebark pine (Pinus albicaulis Engelmann) is a treeline species in the central Rocky Mountains. Its occupation of high elevations previously protected whitebark pine from long-term mountain pine beetle outbreaks. The mountain pine beetle, however, is currently reaching outbreaks of record magnitude in high-elevation whitebark pine. We used a factorial laboratory experiment to compare mountain pine beetle (Dendroctonus ponderosae Hopkins) life history characteristics between a typical host, ...

  17. Substrate use of Pseudovibrio sp. growing in ultra-oligotrophic seawater.

    Directory of Open Access Journals (Sweden)

    Anne Schwedt

    Full Text Available Marine planktonic bacteria often live in habitats with extremely low concentrations of dissolved organic matter (DOM. To study the use of trace amounts of DOM by the facultatively oligotrophic Pseudovibrio sp. FO-BEG1, we investigated the composition of artificial and natural seawater before and after growth. We determined the concentrations of dissolved organic carbon (DOC, total dissolved nitrogen (TDN, free and hydrolysable amino acids, and the molecular composition of DOM by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR-MS. The DOC concentration of the artificial seawater we used for cultivation was 4.4 μmol C L(-1, which was eight times lower compared to the natural oligotrophic seawater we used for parallel experiments (36 μmol C L(-1. During the three-week duration of the experiment, cell numbers increased from 40 cells mL(-1 to 2x10(4 cells mL(-1 in artificial and to 3x10(5 cells mL(-1 in natural seawater. No nitrogen fixation and minor CO2 fixation (< 1% of cellular carbon was observed. Our data show that in both media, amino acids were not the main substrate for growth. Instead, FT-ICR-MS analysis revealed usage of a variety of different dissolved organic molecules, belonging to a wide range of chemical compound groups, also containing nitrogen. The present study shows that marine heterotrophic bacteria are able to proliferate with even lower DOC concentrations than available in natural ultra-oligotrophic seawater, using unexpected organic compounds to fuel their energy, carbon and nitrogen requirements.

  18. Pine weevil (Hylobius abietis) antifeedants from lodgepole pine (Pinus contorta).

    Science.gov (United States)

    Bratt, K; Sunnerheim, K; Nordenhem, H; Nordlander, G; Langström, B

    2001-11-01

    Pine weevils (Hylobius abietis) fed less on bark of lodgepole pine (Pinus contorta) than on bark of Scots pine (P. sylvestris). Two pine weevil antifeedants, ethyl trans-cinnamate and ethyl 2,3-dibromo-3-phenyl-propanoate, were isolated from bark of lodgepole pine. These two compounds significantly reduced pine weevil feeding in a laboratory bioassay. In field assays, the second compound significantly decreased pine weevil damage on planted seedlings. Ethyl 2,3-dibromo-3-phenylpropanoate has not previously been reported as a natural product.

  19. A caveat regarding diatom-inferred nitrogen concentrations in oligotrophic lakes

    Science.gov (United States)

    Arnett, Heather A.; Saros, Jasmine E.; Mast, M. Alisa

    2012-01-01

    Atmospheric deposition of reactive nitrogen (Nr) has enriched oligotrophic lakes with nitrogen (N) in many regions of the world and elicited dramatic changes in diatom community structure. The lakewater concentrations of nitrate that cause these community changes remain unclear, raising interest in the development of diatom-based transfer functions to infer nitrate. We developed a diatom calibration set using surface sediment samples from 46 high-elevation lakes across the Rocky Mountains of the western US, a region spanning an N deposition gradient from very low to moderate levels (phosphorus, and hypolimnetic water temperature were related to diatom distributions. A transfer function was developed for nitrate and applied to a sedimentary diatom profile from Heart Lake in the central Rockies. The model coefficient of determination (bootstrapping validation) of 0.61 suggested potential for diatom-inferred reconstructions of lakewater nitrate concentrations over time, but a comparison of observed versus diatom-inferred nitrate values revealed the poor performance of this model at low nitrate concentrations. Resource physiology experiments revealed that nitrogen requirements of two key taxa were opposite to nitrate optima defined in the transfer function. Our data set reveals two underlying ecological constraints that impede the development of nitrate transfer functions in oligotrophic lakes: (1) even in lakes with nitrate concentrations below quantification (<1 μg L−1), diatom assemblages were already dominated by species indicative of moderate N enrichment; (2) N-limited oligotrophic lakes switch to P limitation after receiving only modest inputs of reactive N, shifting the controls on diatom species changes along the length of the nitrate gradient. These constraints suggest that quantitative inferences of nitrate from diatom assemblages will likely require experimental approaches.

  20. Responses of fen plant species to groundwater level and light intensity

    NARCIS (Netherlands)

    Kotowski, W; van Andel, J; van Diggelen, R; Hogendorf, J.

    Characteristic species of sedge-moss fen communities occur in constantly wet, nutrient-poor sites with a high penetration of light through the vegetation canopy. We studied the effects of water table depth and differences in light intensity on the performance of fen species. Three fen species (Carex

  1. Understanding the Groundwater Hydrology of a Geographically-Isolated Prairie Fen: Implications for Conservation.

    Science.gov (United States)

    Sampath, Prasanna Venkatesh; Liao, Hua-Sheng; Curtis, Zachary Kristopher; Doran, Patrick J; Herbert, Matthew E; May, Christopher A; Li, Shu-Guang

    2015-01-01

    The sources of water and corresponding delivery mechanisms to groundwater-fed fens are not well understood due to the multi-scale geo-morphologic variability of the glacial landscape in which they occur. This lack of understanding limits the ability to effectively conserve these systems and the ecosystem services they provide, including biodiversity and water provisioning. While fens tend to occur in clusters around regional groundwater mounds, Ives Road Fen in southern Michigan is an example of a geographically-isolated fen. In this paper, we apply a multi-scale groundwater modeling approach to understand the groundwater sources for Ives Road fen. We apply Transition Probability geo-statistics on more than 3000 well logs from a state-wide water well database to characterize the complex geology using conditional simulations. We subsequently implement a 3-dimensional reverse particle tracking to delineate groundwater contribution areas to the fen. The fen receives water from multiple sources: local recharge, regional recharge from an extensive till plain, a regional groundwater mound, and a nearby pond. The regional sources deliver water through a tortuous, 3-dimensional "pipeline" consisting of a confined aquifer lying beneath an extensive clay layer. Water in this pipeline reaches the fen by upwelling through openings in the clay layer. The pipeline connects the geographically-isolated fen to the same regional mound that provides water to other fen clusters in southern Michigan. The major implication of these findings is that fen conservation efforts must be expanded from focusing on individual fens and their immediate surroundings, to studying the much larger and inter-connected hydrologic network that sustains multiple fens.

  2. Calcareous Fens - Source Feature Points

    Data.gov (United States)

    Minnesota Department of Natural Resources — Pursuant to the provisions of Minnesota Statutes, section 103G.223, this database contains points that represent calcareous fens as defined in Minnesota Rules, part...

  3. Specific-activity and concentration model applied to cesium movement in an oligotrophic lake

    International Nuclear Information System (INIS)

    Vanderploeg, H.A.; Booth, R.S.; Clark, F.H.

    1975-01-01

    A linear systems-analysis model was derived to simulate the time-dependent dynamics of specific activity and concentration of radionuclides in aquatic systems. Transfer coefficients were determined for movement of 137 Cs in the components of an oligotrophic lake. These coefficients were defined in terms of basic environmental and ecological data so that the model can be applied to a wide variety of sites. Simulations with a model that ignored sediment--water interactions predicted much higher 137 Cs specific activities in the lake water and biota than did those with the complete model. Comparing 137 Cs concentrations predicted by the model with concentrations reported for the biota of an experimentally contaminated oligotrophic lake indicated that the transfer coefficients derived for the biota are adequate

  4. Hurricane Katrina winds damaged longleaf pine less than loblolly pine

    Science.gov (United States)

    Kurt H. Johnsen; John R. Butnor; John S. Kush; Ronald C. Schmidtling; C. Dana. Nelson

    2009-01-01

    Some evidence suggests that longleaf pine might be more tolerant of high winds than either slash pine (Pinus elliotii Englem.) or loblolly pine (Pinus taeda L.). We studied wind damage to these three pine species in a common garden experiment in southeast Mississippi following Hurricane Katrina,...

  5. Dendrochronologically dated pine stumps document phase-wise bog expansion at a northwest German site between ca. 6700 and ca. 3400 BC

    Science.gov (United States)

    Maike Achterberg, Inke Elisabeth; Eckstein, Jan; Birkholz, Bernhard; Bauerochse, Andreas; Leuschner, Hanns Hubert

    2018-01-01

    The investigated northwest German mire site at Totes Moor is densely covered with subfossil pine stumps (Pinus sylvestris L.) from the fen-bog transition. This facilitates the spatio-temporal reconstruction of mire development, which is based on 212 in situ tree stumps in the case study presented here. Six dendrochronologically dated site chronologies together cover 2345 years between 6703 and 3403 BC. The gaps in between are 6 to 550 years long. Additionally, a floating chronology of 309 years, containing 30 trees, was radiocarbon-dated to the beginning of the 7th millennium cal BC. Peat-stratigraphical survey was carried out additionally, and elevations a.s.l. were determined at several locations. Tree dying-off phases, which indicate water level rise at the site, mostly in context of the local fen-bog transition, are evident for ca. 6600-6450, ca. 6350-5750, ca. 5300-4900, ca. 4700-4550, ca. 3900-3850, ca. 3700-3600, ca. 3500-3450 and ca. 3400 BC. The spatial distribution of the dated in situ trees illustrates the phase-wise expansion of raised bog over fen peat at the site. The documented bog expansion pulses likely correspond to climatic wet sifts.

  6. Actividad antioxidante de los compuestos fenólicos

    Directory of Open Access Journals (Sweden)

    Maestro Durán, R.

    1993-04-01

    Full Text Available This review deals with the oxidation processes induced by light and atmospheric oxygen, as well as the protective action on antioxidant compounds. The available data on the synthetic antioxidants and the problems associated to their use, together with the presence of natural phenolic antioxidants in plants, have been revised. These phenolic antioxidants have been classified in families: phenolic alcohols and acids, cinnamic acids, coumarins, favonoids (flavones and isoflavones, flavonols, flavanones and other phenolic compounds.

    Este trabajo recoge los estudios sobre los mecanismos de oxidación producida por la luz y el oxígeno del aire y sobre la protección de los compuestos antioxidantes contra esta oxidación. Se han revisado los datos existentes sobre los inconvenientes de los antioxidantes sintéticos, que aconsejan sustituirlos por otros naturales y sobre la presencia de antioxidantes naturales de carácter fenólico en las plantas. Los antioxidantes fenólicos se han agrupado por familias: alcoholes y ácidos fenólicos, ácidos cinámicos, cumarinas, flavonoides (flavonas e isoflavonas, flavonoles, flavanonas y otros compuestos fenólicos.

  7. Fens and their rare plants in the Beartooth Mountains, Shoshone National Forest, Wyoming

    Science.gov (United States)

    Bonnie Heidel; Walter Fertig; Sabine Mellmann-Brown; Kent E. Houston; Kathleen A. Dwire

    2017-01-01

    Fens are common wetlands in the Beartooth Mountains on the Shoshone National Forest, Clarks Fork Ranger District, in Park County, Wyoming. Fens harbor plant species found in no other habitats, and some rare plants occurring in Beartooth fens are found nowhere else in Wyoming. This report summarizes the studies on Beartooth fens from 1962 to 2009, which have contributed...

  8. Lake level fluctuations boost toxic cyanobacterial "oligotrophic blooms".

    Directory of Open Access Journals (Sweden)

    Cristiana Callieri

    Full Text Available Global warming has been shown to strongly influence inland water systems, producing noticeable increases in water temperatures. Rising temperatures, especially when combined with widespread nutrient pollution, directly favour the growth of toxic cyanobacteria. Climate changes have also altered natural water level fluctuations increasing the probability of extreme events as dry periods followed by heavy rains. The massive appearance of Dolichospermum lemmermannii ( = planktonic Anabaena, a toxic species absent from the pelagic zone of the subalpine oligotrophic Lake Maggiore before 2005, could be a consequence of the unusual fluctuations of lake level in recent years. We hypothesized that these fluctuations may favour the cyanobacterium as result of nutrient pulses from the biofilms formed in the littoral zone when the lake level is high. To help verify this, we exposed artificial substrates in the lake, and evaluated their nutrient enrichment and release after desiccation, together with measurements of fluctuations in lake level, precipitation and D. lemmermannii population. The highest percentage of P release and the lowest C:P molar ratio of released nutrients coincided with the summer appearance of the D. lemmermannii bloom. The P pulse indicates that fluctuations in level counteract nutrient limitation in this lake and it is suggested that this may apply more widely to other oligotrophic lakes. In view of the predicted increase in water level fluctuations due to climate change, it is important to try to minimize such fluctuations in order to mitigate the occurrence of cyanobacterial blooms.

  9. Substrate Use of Pseudovibrio sp. Growing in Ultra-Oligotrophic Seawater

    Science.gov (United States)

    Schwedt, Anne; Seidel, Michael; Dittmar, Thorsten; Simon, Meinhard; Bondarev, Vladimir; Romano, Stefano; Lavik, Gaute; Schulz-Vogt, Heide N.

    2015-01-01

    Marine planktonic bacteria often live in habitats with extremely low concentrations of dissolved organic matter (DOM). To study the use of trace amounts of DOM by the facultatively oligotrophic Pseudovibrio sp. FO-BEG1, we investigated the composition of artificial and natural seawater before and after growth. We determined the concentrations of dissolved organic carbon (DOC), total dissolved nitrogen (TDN), free and hydrolysable amino acids, and the molecular composition of DOM by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR-MS). The DOC concentration of the artificial seawater we used for cultivation was 4.4 μmol C L-1, which was eight times lower compared to the natural oligotrophic seawater we used for parallel experiments (36 μmol C L -1). During the three-week duration of the experiment, cell numbers increased from 40 cells mL-1 to 2x104 cells mL -1 in artificial and to 3x105 cells mL -1 in natural seawater. No nitrogen fixation and minor CO2 fixation (seawater, using unexpected organic compounds to fuel their energy, carbon and nitrogen requirements. PMID:25826215

  10. Formalized classification of European fen vegetation at the alliance level

    DEFF Research Database (Denmark)

    Peterka, Tomáš; Hájek, Michal; Jiroušek, Martin

    2017-01-01

    Aims Phytosociological classification of fen vegetation (Scheuchzerio palustris-Caricetea fuscae class) differs among European countries. Here we propose a unified vegetation classification of European fens at the alliance level, provide unequivocal assignment rules for individual vegetation plot...

  11. Scientific designs of pine seeds and pine cones for species conservation

    Science.gov (United States)

    Song, Kahye; Yeom, Eunseop; Kim, Hyejeong; Lee, Sang Joon

    2015-11-01

    Reproduction and propagation of species are the most important missions of every living organism. For effective species propagation, pine cones fold their scales under wet condition to prevent seeds from short-distance dispersal. They open and release their embedded seeds on dry and windy days. In this study, the micro-/macro-scale structural characteristics of pine cones and pine seeds are studied using various imaging modalities. Since the scales of pine cones consist of dead cells, the folding motion is deeply related to structural changes. The scales of pine cones consist of three layers. Among them, bract scales are only involved in collecting water. This makes pine cones reduce the amount of water and minimize the time spent on structural changes. These systems also involve in drying and recovery of pine cones. In addition, pine cones and pine seeds have advantageous structures for long-distance dispersal and response to natural disaster. Owing to these structural features, pine seeds can be released safely and efficiently, and these types of structural advantages could be mimicked for practical applications. This research was financially supported by the Creative Research Initiative of the Ministry of Science, ICT and Future Planning (MSIP) and the National Research Foundation (NRF) of Korea (Contract grant number: 2008-0061991).

  12. Bivalve nutrient cycling : nutrient turnover by suspended mussel communities in oligotrophic fjords

    NARCIS (Netherlands)

    Jansen, H.M.

    2012-01-01

    This study examined a range of eco-physiological processes (i.e filtration, growth, excretion,

    faeces production) and feedback mechanisms with the aim to investigate the contribution of

    suspended mussel Mytilus edulis communities to nutrient cycling in oligotrophic

  13. The hydrological functioning of a constructed fen wetland watershed.

    Science.gov (United States)

    Ketcheson, Scott J; Price, Jonathan S; Sutton, Owen; Sutherland, George; Kessel, Eric; Petrone, Richard M

    2017-12-15

    Mine reclamation requires the reconstruction of entire landforms and drainage systems. The hydrological regime of reclaimed landscapes will be a manifestation of the processes operating within the individual landforms that comprise it. Hydrology is the most important process regulating wetland function and development, via strong controls on chemical and biotic processes. Accordingly, this research addresses the growing and immediate need to understand the hydrological processes that operate within reconstructed landscapes following resource extraction. In this study, the function of a constructed fen watershed (the Nikanotee Fen watershed) is evaluated for the first two years following construction (2013-2014) and is assessed and discussed within the context of the construction-level design. The system design was capable of sustaining wet conditions within the Nikanotee Fen during the snow-free period in 2013 and 2014, with persistent ponded water in some areas. Evapotranspiration dominated the water fluxes from the system. These losses were partially offset by groundwater discharge from the upland aquifer, which demonstrated strong hydrologic connectivity with the fen in spite of most construction materials having lower than targeted saturated hydraulic conductivities. However, the variable surface infiltration rates and thick placement of a soil-capping layer constrained recharge to the upland aquifer, which remained below designed water contents in much of the upland. These findings indicate that it is possible to engineer the landscape to accommodate the hydrological functions of a fen peatland following surface oil sands extraction. Future research priorities should include understanding the storage and release of water within coarse-grained reclaimed landforms as well as evaluating the relative importance of external water sources and internal water conservation mechanisms for the viability of fen ecosystems over the longer-term. Copyright © 2017 Elsevier B

  14. Characterization of Fen-Daqu Through Multivariate Statistical Analysis of H-1 NMR Spectroscopic Data

    NARCIS (Netherlands)

    Van-Diep, L.; Zheng, X.; Ma, K.; Chen, J.Y.; Han, B.Z.; Nout, M.J.R.

    2011-01-01

    J. Inst. Brew. 117(4), 516-522, 2011 Fen liquor is typical of Chinese light-flavour liquor (alcoholic spirit), which is fermented from sorghum with Fen-Daqu powder. Fen-Daqu is a saccharifying agent and fermentation starter in this fermentation process and in Fen traditional vinegar. To investigate

  15. Mountain pine beetle infestation of lodgepole pine in areas of water diversion.

    Science.gov (United States)

    Smolinski, Sharon L; Anthamatten, Peter J; Bruederle, Leo P; Barbour, Jon M; Chambers, Frederick B

    2014-06-15

    The Rocky Mountains have experienced extensive infestations from the mountain pine beetle (Dendroctonus ponderosae Hopkins), affecting numerous pine tree species including lodgepole pine (Pinus contorta Dougl. var. latifolia). Water diversions throughout the Rocky Mountains transport large volumes of water out of the basins of origin, resulting in hydrologic modifications to downstream areas. This study examines the hypothesis that lodgepole pine located below water diversions exhibit an increased incidence of mountain pine beetle infestation and mortality. A ground survey verified diversion structures in a portion of Grand County, Colorado, and sampling plots were established around two types of diversion structures, canals and dams. Field studies assessed mountain pine beetle infestation. Lodgepole pines below diversions show 45.1% higher attack and 38.5% higher mortality than lodgepole pines above diversions. These findings suggest that water diversions are associated with increased infestation and mortality of lodgepole pines in the basins of extraction, with implications for forest and water allocation management. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Should ponderosa pine be planted on lodgepole pine sites?

    Science.gov (United States)

    P.H. Cochran

    1984-01-01

    Repeated radiation frosts caused no apparent harm to the majority of lodgepole pine (Pinus contorta Dougl.) seedlings planted on a pumice flat in south-central Oregon. For most but not all of the ponderosa pine (Pinus ponderosa Dougl.) seedlings planted with the lodgepole pine, however, damage from radiation frost resulted in...

  17. Nantucket Pine Tip Moth Control and Loblolly Pine Growth in Intensive Pine Culture: Two-Year Results

    Science.gov (United States)

    David L. Kulhavy; Jimmie L. Yeiser; L. Allen Smith

    2004-01-01

    Twenty-two treatments replicated four times were applied to planted loblolly pine, Pinus taeda L. on bedded industrial forest land in east Texas for measurement of growth impact of Nantucket pine tip moth (NPTM), Rhyacionia frustrana (Comstock), and effects on pine growth over 2 years. Treatments were combinations of Velpar, Oust, and Arsenal...

  18. Ecology of aerobic anoxygenic phototrophic bacteria along an oligotrophic gradient in the Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    D. Lamy

    2011-04-01

    Full Text Available Aerobic anoxygenic phototrophic (AAP bacteria are photoheterotrophic prokaryotes able to use both light and organic substrates for energy production. They are widely distributed in coastal and oceanic environments and may contribute significantly to the carbon cycle in the upper ocean. To better understand questions regarding links between the ecology of these photoheterotrophic bacteria and the trophic status of water masses, we examined their horizontal and vertical distribution and the effects of nutrient additions on their growth along an oligotrophic gradient in the Mediterranean Sea. Concentrations of bacteriochlorophyll-a (BChl-a and AAP bacterial abundance decreased from the western to the eastern basin of the Mediterranean Sea and were linked with concentrations of chlorophyll-a, nutrient and dissolved organic carbon. Inorganic nutrient and glucose additions to surface seawater samples along the oligotrophic gradient revealed that AAP bacteria were nitrogen- and carbon-limited in the ultraoligotrophic eastern basin. The intensity of the AAP bacterial growth response generally differed from that of the total bacterial growth response. BChl-a quota of AAP bacterial communities was significantly higher in the eastern basin than in the western basin, suggesting that reliance on phototrophy varied along the oligotrophic gradient and that nutrient and/or carbon limitation favors BChl-a synthesis.

  19. El fenómeno de envejecimiento de los asfaltos

    Directory of Open Access Journals (Sweden)

    Xiomara Vargas

    2010-09-01

    Full Text Available En este trabajo se presenta una revisión actualizada a los resultados del estudio de los procesos de envejecimiento de los asfaltos, encontrados por diversos investigadores, con el fin de profundizar en la comprensión de este fenómeno complejo. Los antecedentes demuestran la evolución del estudio del fenómeno de envejecimiento de los asfaltos, considerado inicialmente como un proceso de endurecimiento físico y progresivamente reconocido como un fenómeno complejo con repercusiones en la durabilidad y las propiedades fisicoquímicas del asfalto. Este documento pretende ser una guía para el emprendimiento de futuras investigaciones relacionadas con el desarrollo de nuevos asfaltos y mezclas asfálticas con propiedades mejoradas.

  20. The growth of Scots pine and the availability of nutrients in old Finnish liming experiments on drained peatlands

    International Nuclear Information System (INIS)

    Nieminen, M.; Paetilae, A.

    1994-01-01

    Liming (with applications of 1000 to 8000 kg/ha) had no long- term (1929-1985) effect on the growth of Scots pine on drained oligotrophic peatlands. Liming plus NPK fertilization had a variable effect on the growth of stands. The same treatment could result in a very different response in different experimental areas. Both liming alone and liming plus NPK fertilization increased the calcium, magnesium and nitrogen contents of peat and decreased the C/Nratio and acidity. Liming plus fertilization decreased needle boron and manganese and increased calcium and nitrogen concentrations. The results of peat and needle analysis indicated that the changes in nitrogen availability to trees caused by liming have not been sufficient enough to affect tree growth. It was also concluded that boron deficiency was the main reason for the lowered yield. (26 refs., 6 tabs., 8 figs.) (author)

  1. Stand structure and vegetation dynamics of a subalpine treed fen in Rocky Mountain National Park, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, J.B. [Colorado State Univ., Fort Collins, CO (United States). Dept. of Biology

    1997-06-01

    The tree population size structure and relationship between tree diameter and age were examined in a subalpine fen and surrounding Picea-Abies forest in northern Colorado. The fen grades from a sedge fen, through an ecotone, to a treed fen (i.e. fen colonized by trees). Tree growth rate varies across the vegetational gradient, with the sedge fen having the slowest growth, and the upland forest having the fastest growth. Differences in growth rate are related to the average size of peat hummocks, with areas containing tall hummocks exhibiting the highest tree growth rates. Size structures display the characteristic reverse-J distribution generally indicative of stable populations, but forest vegetation is expanding into the open regions of the fen, and within the treed fen an increase in Abies lasiocarpa is occurring. These changes are primarily attributed to a positive feedback situation wherein the fen`s surface is built up by peat accumulation. Distinct hummocks form first on the open fen but then coalesce to form raised peat islands in the treed fen. This new substrate provides habitat with a comparatively low water table and allows the growth of mesophytic forest vegetation. A pathway for this vegetational development is proposed. 40 refs., 2 figs.

  2. Characterization of volatile compounds in Fen-Daqu - a traditional Chinese liquor fermentation starter

    NARCIS (Netherlands)

    Van-Diep, L.; Zheng, X.; Chen, J.Y.; Han, B.Z.

    2012-01-01

    Fen-Daqu is a saccharifying agent and fermentation starter for the production of Chinese liquor Fen (alcoholic spirit) and Fen traditional vinegar. The volatile compounds produced at seven incubation steps were analysed by HS-SPME-GC-MS. A total of 83 major volatile compounds were identified,

  3. Novel fen ecosystems in western North Carolina

    Science.gov (United States)

    Wilcox, J. D.

    2012-12-01

    Western North Carolina is mountainous, and groundwater flows from hillslope recharge zones to valley stream and spring discharge zones. Depending on surface topography and geologic conditions, the water table may approach or intersect the ground surface to form seepage wetlands, or fens. Fen ecosystems can be very sensitive to changes in land use, groundwater pumping, and upslope development. This presentation will focus on two sites where historical land use and human activity played important roles in creating or preserving fen ecosystems. Both sites now support—and are being managed to protect—federally endangered flora and fauna. The first site is home to Sarracenia oreophilia, an endangered pitcher plant that thrives on saturated soils with low nutrient content. The site's early history includes tree clearing, drain tile installation, and cattle grazing, while more recent management activities have included drain tile excavation, manual invasive removal, and prescribed burns. A 15-year water-level record indicates seasonal artesian conditions wet a 3m clay unit (K=2E-5 cm/sec) beneath the site, which is able to retain moisture during drier periods. Shorter "clay wetting periods" during drought years (1999-2000; 2007-2008) correspond to reduced clump counts in pitcher-plant surveys. The second site is a former aggregate quarry that now supports over 60 bog turtles (Clemmys muhlenbergii). The biggest threat to this site is encroachment of non-native and invasive multiflora rose (Rosa multiflora) and other large woody species. Management activities include manual removal and prescribed goat herbivory. Current efforts to characterize the springs, water-table, and surface-water flows will be used to detect changes in the future to the hydrologic regime in the fen.

  4. Brevibacterium siliguriense sp nov., a facultatively oligotrophic bacterium isolated from river water

    NARCIS (Netherlands)

    Kumar, A.; Ince, I.A.; Kati, A.; Chakraborty, R.

    2013-01-01

    A Gram-positive-staining, rod-shaped, facultatively oligotrophic bacterial strain, designated MB18(T), was isolated from a water sample collected from the River Mahananda at Siliguri (26 degrees 44' 23.20' N, 88 degrees 25' 22.89' a West-Bengal, India. On the basis of 16S rRNA gene sequence

  5. Fenómeno de Raynaud. Revisión

    OpenAIRE

    Jairo Alonso Rodríguez-Criollo; Daniel Jaramillo-Arroyave

    2014-01-01

    El fenómeno de Raynaud es una respuesta vascular exagerada al frio o al estrés que se manifiesta por cambios de coloración de la piel en diversas localizaciones, característicamente mostrando tres fases distintas que comprenden palidez, cianosis y rubor. La fisiopatología tiene varios componentes y puede tener varias etiologías, que comprenden vasoconstricción, agregación plaquetaria, trombosis y proliferación vascular. Dependiendo de la ausencia o la presencia de enfermedad de base, el fenóm...

  6. Understanding toxicity at the watershed scale : design of the Syncrude Sandhill Fen watershed research project

    International Nuclear Information System (INIS)

    Wytrykush, C.

    2010-01-01

    Fens are peat-accumulating wetlands with a water table consisting of mineral-rich ground or surface water. This study discussed the construction of a fen-type reclaimed wetland constructed in a post-mining oil sands landscape. Syncrude Canada's Sandhill fen watershed project represents the first attempt at constructing a fen wetland in the oil sands region. The wetland and its watershed will be constructed on a soft tailings deposit. The design basis for the fen and watershed was developed by a team of researchers and scientists. The aim of the fen design was to control the salinity caused by tailings consolidation and seepage over time. Methods of mitigating potentially toxic effects from salinity were discussed.

  7. Naturally Occurring Compound Can Protect Pines from the Southern Pine Beetle

    Science.gov (United States)

    B.L. Strom; R.A. Goyer; J.L. Hayes

    1995-01-01

    The southern pine beetle (SPB), Dendroctonus frontalis, is the most destructive insect pest of southern pine forests. This tiny insect, smaller than a grain of rice, is responsible for killing pine timber worth millions of dollars on a periodic basis in Louisiana.

  8. Post-fire regeneration of vegetation on sandy oligotrophic soil, in Itabaiana, Sergipe, Brazil

    Directory of Open Access Journals (Sweden)

    Túlio Vinicius Paes Dantas

    2015-07-01

    Full Text Available Two models of post-disturbance regeneration of vegetation in areas of oligotrophic soils have been proposed for temperate regions. The first model is characterized by rapid recovery of the floristic composition, due to the fire resistance of plants; while in the second model, the fire causes extensive mortality and the recovery occurs by recruitment from the seed bank. Since these models have been rarely tested in tropical oligotrophic environments, we applied them in the analysis of floristic compositions in three areas with different post-fire regeneration times in Sergipe State, Brazil. The regeneration followed the seed bank recruitment model in places of bare ground, with a progressive increase in plant density and changes in the relative abundance and dominance of the populations along the successional process. The parameters that best allowed the succession evaluation were the floral similarity, plant height and density, which increased as regeneration progressed. The stem diameter and tillering were inconclusive as parameters for assessing the regeneration progress.

  9. Water level influences on body condition of Geophagus brasiliensis (Perciformes: Cichlidae in a Brazilian oligotrophic reservoir

    Directory of Open Access Journals (Sweden)

    Alejandra Filippo Gonzalez Neves dos Santos

    Full Text Available Effects of water level fluctuations on body condition of Geophagus brasiliensis were studied in a 30 km² Brazilian oligotrophic reservoir. Physiological condition (K and gonadosomatic index (GSI were compared according to water level (low and high. Females' best conditions were associated to higher resources availability during high water, since gonad development did not change between low and high water. Males' condition did not change between water levels, while the highest gonad development occurred in low water. Females presented higher reproductive investment than males, which allocated most of energy for somatic development. This strategy could be a mechanism to undergo the stress caused by oligotrophic characteristics of the reservoir enhanced during low water level.

  10. El fenómeno de bullying en Colombia

    Directory of Open Access Journals (Sweden)

    Ángela Paola Contreras Álvarez

    2013-01-01

    Full Text Available El presente artículo describe el nefasto fenómeno de violencia y hostigamiento en ambientes escolares denominado bullying o matoneo escolar, el cual, aunque ha sido analizado desde finales de los años setenta en los países escandinavos, tuvo auge en Colombia en el año 2000, adquiriendo fuerza y permanencia con el uso de redes sociales, evidenciando la falta de políticas nacionales educativas para la atención e intervención del problema, al igual que el olvido de educación en derechos humanos y resolución pacífica de conflictos en los colegios. Esta problemática se desarrolla a través del significado del bullying, la descripción de sus antecedentes, descripción general del fenómeno, relación de los deberes del Estado frente al tema, la concepción del fenómeno desde la perspectiva de la Corte Constitucional, concluyendo en algunas sugerencias para abordar la problemática escolar.

  11. Saharan dust inputs and high UVR levels jointly alter the metabolic balance of marine oligotrophic ecosystems

    Science.gov (United States)

    Cabrerizo, Marco J.; Medina-Sánchez, Juan Manuel; González-Olalla, Juan Manuel; Villar-Argaiz, Manuel; Carrillo, Presentación

    2016-10-01

    The metabolic balance of the most extensive bioma on the Earth is a controversial topic of the global-change research. High ultraviolet radiation (UVR) levels by the shoaling of upper mixed layers and increasing atmospheric dust deposition from arid regions may unpredictably alter the metabolic state of marine oligotrophic ecosystems. We performed an observational study across the south-western (SW) Mediterranean Sea to assess the planktonic metabolic balance and a microcosm experiment in two contrasting areas, heterotrophic nearshore and autotrophic open sea, to test whether a combined UVR × dust impact could alter their metabolic balance at mid-term scales. We show that the metabolic state of oligotrophic areas geographically varies and that the joint impact of UVR and dust inputs prompted a strong change towards autotrophic metabolism. We propose that this metabolic response could be accentuated with the global change as remote-sensing evidence shows increasing intensities, frequencies and number of dust events together with variations in the surface UVR fluxes on SW Mediterranean Sea. Overall, these findings suggest that the enhancement of the net carbon budget under a combined UVR and dust inputs impact could contribute to boost the biological pump, reinforcing the role of the oligotrophic marine ecosystems as CO2 sinks.

  12. HYDRO-ECOLOGICAL ANALYSIS OF THE FEN SYSTEM LIEPER POSSE, EASTERN GERMANY

    NARCIS (Netherlands)

    VANDIGGELEN, R; GROOTJANS, AP; KEMMERS, RH; KOOIJMAN, AM; SUCCOW, M; DEVRIES, NPJ; VANWIRDUM, G; Vries, N.P.J. de; Wirdum, G. van

    The Lieper Posse is a calcareous, ground water-fed fen system, situated in the end-moraine area of northeastern Germany. Nowadays the fen is partly drained and the vegetation adversely affected; hence regeneration measures are considered. Here we report a pilot survey of the actual vegetation cover

  13. Transcriptome resources and functional characterization of monoterpene synthases for two host species of the mountain pine beetle, lodgepole pine (Pinus contorta) and jack pine (Pinus banksiana)

    Science.gov (United States)

    2013-01-01

    Background The mountain pine beetle (MPB, Dendroctonus ponderosae) epidemic has affected lodgepole pine (Pinus contorta) across an area of more than 18 million hectares of pine forests in western Canada, and is a threat to the boreal jack pine (Pinus banksiana) forest. Defence of pines against MPB and associated fungal pathogens, as well as other pests, involves oleoresin monoterpenes, which are biosynthesized by families of terpene synthases (TPSs). Volatile monoterpenes also serve as host recognition cues for MPB and as precursors for MPB pheromones. The genes responsible for terpene biosynthesis in jack pine and lodgepole pine were previously unknown. Results We report the generation and quality assessment of assembled transcriptome resources for lodgepole pine and jack pine using Sanger, Roche 454, and Illumina sequencing technologies. Assemblies revealed transcripts for approximately 20,000 - 30,000 genes from each species and assembly analyses led to the identification of candidate full-length prenyl transferase, TPS, and P450 genes of oleoresin biosynthesis. We cloned and functionally characterized, via expression of recombinant proteins in E. coli, nine different jack pine and eight different lodgepole pine mono-TPSs. The newly identified lodgepole pine and jack pine mono-TPSs include (+)-α-pinene synthases, (-)-α-pinene synthases, (-)-β-pinene synthases, (+)-3-carene synthases, and (-)-β-phellandrene synthases from each of the two species. Conclusion In the absence of genome sequences, transcriptome assemblies are important for defence gene discovery in lodgepole pine and jack pine, as demonstrated here for the terpenoid pathway genes. The product profiles of the functionally annotated mono-TPSs described here can account for the major monoterpene metabolites identified in lodgepole pine and jack pine. PMID:23679205

  14. Transcriptome resources and functional characterization of monoterpene synthases for two host species of the mountain pine beetle, lodgepole pine (Pinus contorta) and jack pine (Pinus banksiana).

    Science.gov (United States)

    Hall, Dawn E; Yuen, Macaire M S; Jancsik, Sharon; Quesada, Alfonso Lara; Dullat, Harpreet K; Li, Maria; Henderson, Hannah; Arango-Velez, Adriana; Liao, Nancy Y; Docking, Roderick T; Chan, Simon K; Cooke, Janice Ek; Breuil, Colette; Jones, Steven Jm; Keeling, Christopher I; Bohlmann, Jörg

    2013-05-16

    The mountain pine beetle (MPB, Dendroctonus ponderosae) epidemic has affected lodgepole pine (Pinus contorta) across an area of more than 18 million hectares of pine forests in western Canada, and is a threat to the boreal jack pine (Pinus banksiana) forest. Defence of pines against MPB and associated fungal pathogens, as well as other pests, involves oleoresin monoterpenes, which are biosynthesized by families of terpene synthases (TPSs). Volatile monoterpenes also serve as host recognition cues for MPB and as precursors for MPB pheromones. The genes responsible for terpene biosynthesis in jack pine and lodgepole pine were previously unknown. We report the generation and quality assessment of assembled transcriptome resources for lodgepole pine and jack pine using Sanger, Roche 454, and Illumina sequencing technologies. Assemblies revealed transcripts for approximately 20,000 - 30,000 genes from each species and assembly analyses led to the identification of candidate full-length prenyl transferase, TPS, and P450 genes of oleoresin biosynthesis. We cloned and functionally characterized, via expression of recombinant proteins in E. coli, nine different jack pine and eight different lodgepole pine mono-TPSs. The newly identified lodgepole pine and jack pine mono-TPSs include (+)-α-pinene synthases, (-)-α-pinene synthases, (-)-β-pinene synthases, (+)-3-carene synthases, and (-)-β-phellandrene synthases from each of the two species. In the absence of genome sequences, transcriptome assemblies are important for defence gene discovery in lodgepole pine and jack pine, as demonstrated here for the terpenoid pathway genes. The product profiles of the functionally annotated mono-TPSs described here can account for the major monoterpene metabolites identified in lodgepole pine and jack pine.

  15. Field Tests of Pine Oil as a Repellent for Southern Pine Bark Beetles

    Science.gov (United States)

    J.C. Nod; F.L. Hastings; A.S. Jones

    1990-01-01

    An experimental mixture of terpene hydrocarbons derived from wood pulping, BBR-2, sprayed on the lower 6 m of widely separated southern pine trees did not protect nearby trees from southern pine beetle attacks. Whether treated trees were protected from southern pine beetle was inconclusive. The pine oil mixture did not repellpsfrom treated trees or nearby untreated...

  16. Climate influences on whitebark pine mortality from mountain pine beetle in the Greater Yellowstone Ecosystem

    Science.gov (United States)

    Polly C. Buotte; Jeffrey A. Hicke; Haiganoush K. Preisler; John T. Abatzoglou; Kenneth F. Raffa; Jesse A. Logan

    2016-01-01

    Extensive mortality of whitebark pine, beginning in the early to mid-2000s, occurred in the Greater Yellowstone Ecosystem (GYE) of the western USA, primarily from mountain pine beetle but also from other threats such as white pine blister rust. The climatic drivers of this recent mortality and the potential for future whitebark pine mortality from mountain pine beetle...

  17. Ponderosa pine ecosystems

    Science.gov (United States)

    Russell T. Graham; Theresa B. Jain

    2005-01-01

    Ponderosa pine is a wide-ranging conifer occurring throughout the United States, southern Canada, and northern Mexico. Since the 1800s, ponderosa pine forests have fueled the economies of the West. In western North America, ponderosa pine grows predominantly in the moist and dry forests. In the Black Hills of South Dakota and the southern portion of its range, the...

  18. Conservation and Biodiversity of Rich Fens

    DEFF Research Database (Denmark)

    Andersen, Dagmar Kappel

    2014-01-01

    Rich fen is a habitat type dependent on a constant supply of nutrient poor, calcium rich groundwater. A high, stable groundwater table, relatively high pH combined with nutrient poor conditions support a special and very species rich vegetation including many rare and threatened plant species. In...

  19. Phytoplankton biovolume is independent from the slope of the size spectrum in the oligotrophic atlantic ocean

    KAUST Repository

    Moreno-Ostos, Enrique; Blanco, José Marí a; Agusti, Susana; Lubiá n, Luis M.; Rodrí guez, Valeriano; Palomino, Roberto L.; Llabré s, Moira; Rodrí guez, Jaime

    2015-01-01

    high phytoplankton biovolume in productive regions with flatter spectrum slope and the opposite in oligotrophic ecosystems. Rather than this, the relationship between high biovolume phytoplankton assemblages and flatter size-abundance spectra does

  20. A ponderosa pine-lodgepole pine spacing study in central Oregon: results after 20 years.

    Science.gov (United States)

    K.W. Seidel

    1989-01-01

    The growth response after 20 years from an initial spacing study established in a ponderosa pine (Pinus ponderosa Dougl. ex Laws.) and lodgepole pine (Pinus contorta Dougl. ex Loud.) plantation was measured in central Oregon. The study was designed to compare the growth rates of pure ponderosa pine, pure lodgepole pine, and a...

  1. Fungal Diversity in a Dark Oligotrophic Volcanic Ecosystem (DOVE on Mount Erebus, Antarctica

    Directory of Open Access Journals (Sweden)

    Hubert Staudigel

    2013-05-01

    Full Text Available Fumarolic Ice caves on Antarctica’s Mt. Erebus contain a dark oligotrophic volcanic ecosystem (DOVE and represent a deep biosphere habitat that can provide insight into microbial communities that utilize energy sources other than photosynthesis. The community assembly and role of fungi in these environments remains largely unknown. However, these habitats could be relatively easily contaminated during human visits. Sixty-one species of fungi were identified from soil clone libraries originating from Warren Cave, a DOVE on Mt. Erebus. The species diversity was greater than has been found in the nearby McMurdo Dry Valleys oligotrophic soil. A relatively large proportion of the clones represented Malassezia species (37% of Basidomycota identified. These fungi are associated with skin surfaces of animals and require high lipid content for growth, indicating that contamination may have occurred through the few and episodic human visits in this particular cave. These findings highlight the importance of fungi to DOVE environments as well as their potential use for identifying contamination by humans. The latter offers compelling evidence suggesting more strict management of these valuable research areas.

  2. Establishing Longleaf Pine Seedlings Under a Loblolly Pine Canopy (User’s Guide)

    Science.gov (United States)

    2017-02-01

    longleaf pine forests (Figure 1) for the diverse values they provide. These forests afford abundant recreational opportunities like hiking , bird...combined herbicide-fertilizer treatments that might benefit planted longleaf pine seedlings after planting. In addition to measuring longleaf pine

  3. Examining the peat-accumulating potential of fen vegetation in the context of fed restoration of harvested peatlands

    Energy Technology Data Exchange (ETDEWEB)

    Graf, M.; Rochefort, L. [Laval Univ., Quebec City, PQ (Canada). Dept. de Phytologie, Peatland Ecology and Research Group

    2009-07-01

    The return of peat-accumulating function is an important long-term goal in peatland restoration. However, researchers do not yet know which vegetation groups increase the ability of ecosystems to accumulate peat in fens. This study assessed the decomposition rates of 3 vegetation species typical to undisturbed fen regions, and 3 species that spontaneously colonize harvested fens. All species were incubated in a harvest fen restoration site as well as at an undisturbed fen in order to compare decomposition rates according to different environmental conditions. The study showed that the average exponential decay coefficient for all species was higher at the harvested fen site. The decay coefficient varied only slightly between undisturbed and harvested fens, despite wide variations in hydrological conditions. Litter type had the most significant impact on decomposition rates. Annual primary production of the species was also measured in order to estimate the peat accumulating capacity of each species. Results showed that Scirpus cyperinus primary annual production rates were 3 times higher than the other studied species. It was concluded that the harvested fen sites have a higher peat-accumulating potential than undisturbed fens. 60 refs., 2 tabs., 2 figs.

  4. Carbon and phosphorus regulating bacterial metabolism in oligotrophic boreal lakes

    DEFF Research Database (Denmark)

    Vidal, L. O.; Graneli, W.; Daniel, C. B.

    2011-01-01

    This study focused on how phosphorus and carbon control pelagic bacteria in lakes over a gradient of dissolved organic carbon (DOC from 6.7 to 29.5 mg C L(-1)) and phosphorus (P-tot from 5 to 19 mu g L(-1)). Five oligotrophic lakes in southern Sweden were sampled in late autumn. Phosphate...... carbon mineralization in this kind of system during autumn is conditioned by the combined availability of labile carbon and phosphorus, with the assimilated carbon mainly transformed to inorganic carbon in respiration, contributing to CO(2) supersaturation in these systems....

  5. Decomposition of Carex and Sphagnum litter in two mesotrophic fens differing in dominant plant species

    NARCIS (Netherlands)

    Scheffer, R.A.; Van Logtestijn, R. S P; Verhoeven, J. T A

    2001-01-01

    Peatlands can be classified into fens and bogs based on their hydrology. Development of fens to bogs is accompanied by the invasion of Sphagnum species. The purpose of this study was to determine how the decomposition process in fens is influenced by the transition from a vascular plant-dominated

  6. Sugar pine and its hybrids

    Science.gov (United States)

    W. B. Critchfield; B. B. Kinloch

    1986-01-01

    Unlike most white pines, sugar pine (Pinus lambertiana) is severely restricted in its ability to hybridize with other species. It has not been successfully crossed with any other North American white pine, nor with those Eurasian white pines it most closely resembles. Crosses with the dissimilar P. koraiensis and P....

  7. Compostos fenólicos totais e taninos condensados em frutas nativas do cerrado

    Directory of Open Access Journals (Sweden)

    Wesley Silveira Rocha

    2011-12-01

    Full Text Available As frutas nativas do cerrado têm despertado ultimamente interesse crescente, devido às suas propriedades nutricionais e funcionais aliadas ao potencial para agregar valor e conservar a biodiversidade deste bioma. Muitos compostos fenólicos apresentam capacidade antioxidante de neutralizar a atividade de radicais livres gerados no organismo, que estão associados a diversas doenças crônico-degenerativas. O objetivo deste trabalho foi avaliar a eficiência de três soluções extratoras (acetona a 70 %, etanol a 95 % e metanol a 99,8 % e determinar os teores de compostos fenólicos em 10 espécies de frutas nativas do cerrado, utilizando o método de Folin-Ciocalteou para compostos fenólicos totais e o método da vanilina para taninos condensados. A acetona a 70 % mostrou-se como o melhor solvente extrator de compostos fenólicos totais e taninos condensados em frutos de Pouteria gardneriana, Eugenia dysenterica, E. klostzchiana, E. punicifolia, Plinia edulis, Campomanesia sp., fenólicos totais de Brosimium gaudichaudii e taninos condensados de Jaracatia spinosa. O etanol a 95 % foi mais eficiente na extração de fenólicos totais de Jaracatia spinosa e taninos condensados de Brosimium gaudichaudii; o metanol a 99,8 % foi mais eficiente na extração de taninos condensados de Eugenia dysenterica. Os teores de compostos fenólicos totais variaram entre 90 e 327 mg de ácido gálico equivalente por 100g de polpa para as espécies E. dysenterica e E. punicifolia, respectivamente. Os teores de taninos condensados variaram entre 4 e 291 mg de catequina equivalente por 100 g de polpa para as espécies E. dysenterica e E. calcyna, respectivamente. As espécies de frutas do cerrado, avaliadas neste estudo, podem ser consideradas boas fontes de compostos fenólicos totais, sendo que a natureza específica dos diferentes tipos deve ser avaliada em estudos futuros.

  8. Silvicultural treatments for converting loblolly pine to longleaf pine dominance: Effects on planted longleaf pine seedlings

    Science.gov (United States)

    Huifeng Hu; G.Geoff Wang; Joan L. Walker; Benjamin O. Knapp

    2012-01-01

    A field study was installed to test silvicultural treatments for establishing longleaf pine (Pinus palustris Mill) in loblolly pine (P. taeda L.) stands. Harvesting was used to create seven canopy treatments, four with uniformly distributed canopies at different residual basal areas [Control (16.2 m2/ha),...

  9. Characteristics and ontogeny of oligotrophic hardwater lakes in the Forsmark area, central Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Brunberg, A.K.; Blomqvist, P. [Uppsala Univ. (Sweden). Dept. of Limnology

    1999-12-01

    This is the first part of a report characterising the lakes of Uppsala county, with special emphasis on the coastal lakes in the Forsmark area.The aim of the study is to characterise different main types of lakes within the Forsmark area and to create a basis for prediction of their ontogeny, that can be used also for new lakes which due to shoreline displacement will be formed during the next 10 000 years. Areas where future research is needed to fully understand the functioning of the lake ecosystems and their ontogeny should also be identified. This first part of the study identifies and describes one of the most common lake types in the area, the oligotrophic hardwater lake. The geology in the catchments of the Forsmark area includes a bedrock dominated by granites and gneisses, covered by calcareous glacial till and postglacial clay. The catchments are dominated by forest, and the oligotrophic hardwater lakes are to a large extent surrounded by mires. Inflow as well as outflow of water is often diffuse, via the surrounding mire. The lakes are small and shallow, with nutrient poor and highly alkaline water. Three key habitats have been identified within the lakes; the pelagic zone, characterised by low production of biota;, the presumably moderately productive emergent macrophyte zone, dominated by Sphagnum and Phragmites;, and the light exposed soft-bottom zone with Chara meadows and an unusually rich and presumably highly productive microbial sediment community. The oligotrophic hardwater lakes have their origin as depressions in the bottom of the Baltic Sea, which are successively transported upwards due to the land-rise process in the area. As the basins are isolated from the sea , a gradual change from a brackish to freshwater conditions occur. When the lakes have become completely isolated, the oligotrophic hardwater stage follows, due to inflow of carbonate-rich and well buffered groundwater. In the next successional stage, Sphagnum mosses start to

  10. Characteristics and ontogeny of oligotrophic hardwater lakes in the Forsmark area, central Sweden

    International Nuclear Information System (INIS)

    Brunberg, A.K.; Blomqvist, P.

    1999-12-01

    This is the first part of a report characterising the lakes of Uppsala county, with special emphasis on the coastal lakes in the Forsmark area.The aim of the study is to characterise different main types of lakes within the Forsmark area and to create a basis for prediction of their ontogeny, that can be used also for new lakes which due to shoreline displacement will be formed during the next 10 000 years. Areas where future research is needed to fully understand the functioning of the lake ecosystems and their ontogeny should also be identified. This first part of the study identifies and describes one of the most common lake types in the area, the oligotrophic hardwater lake. The geology in the catchments of the Forsmark area includes a bedrock dominated by granites and gneisses, covered by calcareous glacial till and postglacial clay. The catchments are dominated by forest, and the oligotrophic hardwater lakes are to a large extent surrounded by mires. Inflow as well as outflow of water is often diffuse, via the surrounding mire. The lakes are small and shallow, with nutrient poor and highly alkaline water. Three key habitats have been identified within the lakes; the pelagic zone, characterised by low production of biota;, the presumably moderately productive emergent macrophyte zone, dominated by Sphagnum and Phragmites;, and the light exposed soft-bottom zone with Chara meadows and an unusually rich and presumably highly productive microbial sediment community. The oligotrophic hardwater lakes have their origin as depressions in the bottom of the Baltic Sea, which are successively transported upwards due to the land-rise process in the area. As the basins are isolated from the sea , a gradual change from a brackish to freshwater conditions occur. When the lakes have become completely isolated, the oligotrophic hardwater stage follows, due to inflow of carbonate-rich and well buffered groundwater. In the next successional stage, Sphagnum mosses start to

  11. Strategies for managing whitebark pine in the presence of white pine blister rust [Chapter 17

    Science.gov (United States)

    Raymond J. Hoff; Dennis E. Ferguson; Geral I. McDonald; Robert E. Keane

    2001-01-01

    Whitebark pine (Pinus albicaulis) is one of many North American white pine species (Pinus subgenus Strobus) susceptible to the fungal disease white pine blister rust (Cronartium ribicola). Blister rust has caused severe mortality (often reaching nearly 100 percent) in many stands of white bark pine north of 45° latitude in western North America. The rust is slowly...

  12. Low offspring survival in mountain pine beetle infesting the resistant Great Basin bristlecone pine supports the preference-performance hypothesis.

    Directory of Open Access Journals (Sweden)

    Erika L Eidson

    Full Text Available The preference-performance hypothesis states that ovipositing phytophagous insects will select host plants that are well-suited for their offspring and avoid host plants that do not support offspring performance (survival, development and fitness. The mountain pine beetle (Dendroctonus ponderosae, a native insect herbivore in western North America, can successfully attack and reproduce in most species of Pinus throughout its native range. However, mountain pine beetles avoid attacking Great Basin bristlecone pine (Pinus longaeva, despite recent climate-driven increases in mountain pine beetle populations at the high elevations where Great Basin bristlecone pine grows. Low preference for a potential host plant species may not persist if the plant supports favorable insect offspring performance, and Great Basin bristlecone pine suitability for mountain pine beetle offspring performance is unclear. We infested cut bolts of Great Basin bristlecone pine and two susceptible host tree species, limber (P. flexilis and lodgepole (P. contorta pines with adult mountain pine beetles and compared offspring performance. To investigate the potential for variation in offspring performance among mountain pine beetles from different areas, we tested beetles from geographically-separated populations within and outside the current range of Great Basin bristlecone pine. Although mountain pine beetles constructed galleries and laid viable eggs in all three tree species, extremely few offspring emerged from Great Basin bristlecone pine, regardless of the beetle population. Our observed low offspring performance in Great Basin bristlecone pine corresponds with previously documented low mountain pine beetle attack preference. A low preference-low performance relationship suggests that Great Basin bristlecone pine resistance to mountain pine beetle is likely to be retained through climate-driven high-elevation mountain pine beetle outbreaks.

  13. Complex microbiota of a Chinese "Fen" liquor fermentation starter (Fen-Daqu), revealed by culture-dependent and culture-independent methods

    NARCIS (Netherlands)

    Zheng, X.; Zheng, Y.; Han, B.; Zwietering, M.H.; Samson, R.A.; Boekhout, T.; Nout, M.J.R.

    2012-01-01

    Daqu is a traditional fermentation starter that is used for Chinese liquor production. Although partly mechanized, its manufacturing process has remained traditional. We investigated the microbial diversity of Fen-Daqu, a starter for light-flavour liquor, using combined culture-dependent and

  14. El concepto de fenómeno en el joven Heidegger

    Directory of Open Access Journals (Sweden)

    Francisco De Lara

    2008-01-01

    Full Text Available El presente trabajo es una discusión del concepto de fenómeno tal y como éste se encuentra determinado en la filosofía del joven Heidegger. Con ella se pretende ir a la base que permite dilucidar en qué sentido hace éste fenomenología o, en otras palabras, qué idea de filosofía se encuentra expresada bajo el título de hermenéutica fenomenológica. Al hilo de la lectura del concepto de fenómeno como concepto filosófico, esto es, como indicación formal, nos preguntaremos: 1 cómo se toma en consideración lo investigado fenomenológicamente; 2 cómo debe comparecer lo así investigado y 3 si, en efecto, el concepto de fenómeno funciona siempre en Heidegger como una indicación formal o si no puede constatarse en él una cierta ambigüedad.

  15. Lodgepole Pine Dwarf Mistletoe

    Science.gov (United States)

    Frank G. Hawksworth; Oscar J. Dooling

    1984-01-01

    Lodgepole pine dwarf mistletoe (Arceuthobium americanum Nutt. ex Engelm.) is a native, parasitic, seed plant that occurs essentially throughout the range of lodgepole pine in North America. It is the most damaging disease agent in lodgepole pine, causing severe growth loss and increased tree mortality. Surveys in the Rocky Mountains show that the parasite is found in...

  16. Limber pine forests on the leading edge of white pine blister rust distribution in Northern Colorado

    Science.gov (United States)

    Jennifer G. Klutsch; Betsy A. Goodrich; Anna W. Schoettle

    2011-01-01

    The combined threats of the current mountain pine beetle (Dendroctonus ponderosae, MPB) epidemic with the imminent invasion of white pine blister rust (caused by the non-native fungus Cronartium ribicola, WPBR) in limber pine (Pinus flexilis) forests in northern Colorado threatens the limber pine's regeneration cycle and ecosystem function. Over one million...

  17. Mountain pine beetle infestations in relation to lodgepole pine diameters

    Science.gov (United States)

    Walter E. Cole; Gene D. Amman

    1969-01-01

    Tree losses resulting from infestation by the mountain pine beetle (Dendroctonus ponderosae Hopkins) were measured in two stands of lodgepole pine (Pinus contorta Dougl.) where the beetle population had previously been epidemic. Measurement data showed that larger diameter trees were infested and killed first. Tree losses...

  18. Remotely sensed hydrological isolation : a key factor predicting plant species distribution in fens

    NARCIS (Netherlands)

    Sanders, M.E.

    1999-01-01

    In fens the species composition, vegetation structure and succession rate are determined by vegetation management and water chemistry, particularly by the base status and nutrient status. Base-rich and nutrient-rich surface water causes fens to become eutrophied, which leads to an increased

  19. Assessing longleaf pine (Pinus palustris) restoration after southern pine beetle kill using a compact experimental design

    Science.gov (United States)

    J.-P. Berrill; C.M. Dagley

    2010-01-01

    A compact experimental design and analysis is presented of longleaf pine (Pinus palustris) survival and growth in a restoration project in the Piedmont region of Georgia, USA. Longleaf pine seedlings were planted after salvage logging and broadcast burning in areas of catastrophic southern pine beetle (Dendroctonus frontalis) attacks on even-aged mixed pine-hardwood...

  20. Modelado lingüístico de fenómenos complejos

    OpenAIRE

    Álvarez Álvarez, Alberto

    2012-01-01

    Actualmente, es posible adquirir y almacenar grandes volúmenes de datos sobre diferentes fenómenos complejos en muchas áreas importantes. Con el fin de ser útil, esta información debe ser explicada de la manera más comprensible posible, incluyendo los conocimientos previos disponibles sobre el fenómeno que se estudia. Estos objetivos sólo pueden lograrse mediante el uso de lenguaje natural, especialmente si la información final va a ser utilizada por personas no expertas. Por lo tanto, e...

  1. Separating Trends in Whitebark Pine Radial Growth Related to Climate and Mountain Pine Beetle Outbreaks in the Northern Rocky Mountains, USA

    Directory of Open Access Journals (Sweden)

    Saskia L. van de Gevel

    2017-06-01

    Full Text Available Drought and mountain pine beetle (Dendroctonus ponderosae Hopkins outbreaks have affected millions of hectares of high-elevation conifer forests in the Northern Rocky Mountains during the past century. Little research has examined the distinction between mountain pine beetle outbreaks and climatic influence on radial growth in endangered whitebark pine (Pinus albicaulis Engelm. ecosystems. We used a new method to explore divergent periods in whitebark pine radial growth after mountain pine beetle outbreaks across six sites in western Montana. We examined a 100-year history of mountain pine beetle outbreaks and climate relationships in whitebark pine radial growth to distinguish whether monthly climate variables or mountain pine outbreaks were the dominant influence on whitebark pine growth during the 20th century. High mortality of whitebark pines was caused by the overlapping effects of previous and current mountain pine beetle outbreaks and white pine blister rust infection. Wet conditions from precipitation and snowpack melt in the previous summer, current spring, and current summer benefit whitebark pine radial growth during the following growing season. Whitebark pine radial growth and climate relationships were strongest in sites less affected by the mountain pine beetle outbreaks or anthropogenic disturbances. Whitebark pine population resiliency should continue to be monitored as more common periods of drought will make whitebark pines more susceptible to mountain pine beetle attack and to white pine blister rust infection.

  2. Non-Ribes alternate hosts of white pine blister rust: What this discovery means to whitebark pine

    Science.gov (United States)

    Paul J. Zambino; Bryce A. Richardson; Geral I. McDonald; Ned B. Klopfenstein; Mee-Sook. Kim

    2006-01-01

    From early to present-day outbreaks, white pine blister rust caused by the fungus Cronartium ribicola, in combination with mountain pine beetle outbreaks and fire exclusion has caused ecosystem-wide effects for all five-needled pines (McDonald and Hoff 2001). To be successful, efforts to restore whitebark pine will require sound management decisions that incorporate an...

  3. A preliminary carbon budget for two oligotrophic hardwater lakes in the Forsmark area, Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Nilsson, Eva [Uppsala Univ. (Sweden). Dept. of Limnology

    2001-06-01

    The Swedish Nuclear Fuel and Waste Management Co (SKB) is responsible for management and disposal of Swedish radioactive waste. The company is planning to construct repositories that will keep radioactive waste away from humans for hundreds of thousands of years. In a safety assessment of the repositories hypothetical releases are used to evaluate the robustness of the repositories. It is important to know how the radioactive nuclides would react if they were released and by which way they could enter the living biota. SFR are responsible for the disposal of low radioactive waste and close to the nuclear plant in Forsmark there is a storage for low radioactive waste. At the moment this storage is located in the bedrock far below the sea level but due to land-rise in the area it will in the future be located above sea level. Hence, it is of importance to know how the surface ecosystems in the area are functioning. A carbon budget for the aquatic ecosystem above SFR in Oeresundsgrepen exist, but it is also important to have a carbon budget for the surface systems in the Forsmark area since SFR in the future will be situated above sea level. Carbon budgets can be used to get a picture of how an ecosystem functions. The carbon flow shows how carbon is transported through a food web from lower trophic levels, e.g. plants and bacteria to higher trophic levels such as fish. Oligotrophic hardwater lakes are the most important lakes in the Forsmark area. This report aims to give a picture of a potential flow of carbon through the ecosystem in two oligotrophic hard-water lakes, Lake Haellefjaerd and Lake Eckarfjaerden. Macrophyte, mainly Chara, were calculated to make up the largest part of the biomass and production in both lakes. Benthic bacteria and microphytobenthos (benthic photosynthesising microorganisms) were other large contributors to the production. Benthic bacteria were found responsible for a major part of respiration and, hence, consumption of carbon in the

  4. A preliminary carbon budget for two oligotrophic hardwater lakes in the Forsmark area, Sweden

    International Nuclear Information System (INIS)

    Nilsson, Eva

    2001-06-01

    The Swedish Nuclear Fuel and Waste Management Co (SKB) is responsible for management and disposal of Swedish radioactive waste. The company is planning to construct repositories that will keep radioactive waste away from humans for hundreds of thousands of years. In a safety assessment of the repositories hypothetical releases are used to evaluate the robustness of the repositories. It is important to know how the radioactive nuclides would react if they were released and by which way they could enter the living biota. SFR are responsible for the disposal of low radioactive waste and close to the nuclear plant in Forsmark there is a storage for low radioactive waste. At the moment this storage is located in the bedrock far below the sea level but due to land-rise in the area it will in the future be located above sea level. Hence, it is of importance to know how the surface ecosystems in the area are functioning. A carbon budget for the aquatic ecosystem above SFR in Oeresundsgrepen exist, but it is also important to have a carbon budget for the surface systems in the Forsmark area since SFR in the future will be situated above sea level. Carbon budgets can be used to get a picture of how an ecosystem functions. The carbon flow shows how carbon is transported through a food web from lower trophic levels, e.g. plants and bacteria to higher trophic levels such as fish. Oligotrophic hardwater lakes are the most important lakes in the Forsmark area. This report aims to give a picture of a potential flow of carbon through the ecosystem in two oligotrophic hard-water lakes, Lake Haellefjaerd and Lake Eckarfjaerden. Macrophyte, mainly Chara, were calculated to make up the largest part of the biomass and production in both lakes. Benthic bacteria and microphytobenthos (benthic photosynthesising microorganisms) were other large contributors to the production. Benthic bacteria were found responsible for a major part of respiration and, hence, consumption of carbon in the

  5. Unprecedented slow growth and mortality of the rare colonial cyanobacterium, Nostoc zetterstedtii, in oligotrophic lakes

    DEFF Research Database (Denmark)

    Jensen, Kaj Sand; Møller, Claus Lindskov

    2011-01-01

    Centimeter-large colonies of Nostoc zetterstedtii from a Swedish oligotrophic lake had the lowest growth and mortality rates of any studied temperate macrophyte. Annual growth rates at two shallow sites averaged 0.57– 0.73 3 1023 d21, corresponding to doubling times of colony dry weight in 2...

  6. Diferentes Abordagens dos Fenômenos Subjetivos na Obra de B. F. Skinner

    Directory of Open Access Journals (Sweden)

    Henrique Mesquita Pompermaier

    2014-08-01

    Full Text Available Como a análise do comportamento aborda os fenômenos subjetivos? Seria a teoria de eventos privados a única maneira? Guiado por essas questões, o presente trabalho busca apresentar a abordagem dos fenômenos subjetivos na obra de B. F. Skinner, indicando não apenas a teoria de eventos privados, mas também a possibilidade de abordagens alternativas a essa temática, sem referência à privacidade, por exemplo, por meio da magnitude das ações envolvidas nos fenômenos, níveis (aberto e encoberto do comportamento e conceitos disposicionais. Indica-se ainda uma significativa diferença de ênfase na teoria de eventos privados ao longo da obra skinneriana. Por fim, conduz-se uma discussão sobre o papel da teoria de eventos privados na análise do comportamento para a abordagem dos fenômenos subjetivos.

  7. Prokaryotes in subsoil – evidence for spatial separation of oligotrophs and copiotrophs by co-occurrence networks

    Directory of Open Access Journals (Sweden)

    Michael eSchloter

    2015-11-01

    Full Text Available Soil microbial communities provide a wide range of soil functions including nutrient cycling, soil formation, and plant growth promotion. On the small scale, nutrient rich soil hotspots developed from soil animal or plant activity are important drivers for microbial communities and their activity pattern. Nevertheless, in subsoil, the spatial heterogeneity of microbes with diverging lifestyles has been barely considered so far. In this study, the phylogenetic composition of the bacterial and archaeal microbiome based on 16S rRNA gene pyrosequencing was investigated in the soil compartments bulk soil, drilosphere, and rhizosphere in topsoil and in the subsoil of an agricultural field. With co-occurrence network analysis, the spatial separation of typically oligotrophs and heterotrophs in subsoil and hotspots was assessed. Four co-occurring bacterial communities were identified and attributed to bulk topsoil, bulk subsoil, drilosphere, and rhizosphere. The bacterial phyla Proteobacteria and Bacteroidetes, which represent many copiotrophic bacteria, are affiliated to the hotspot communities – the rhizosphere and drilosphere – both in topsoil and subsoil. Acidobacteria, Actinobacteria, Gemmatimonadetes, Planctomycetes, and Verrucomicrobia with many oligotrophic bacteria, are the abundant groups of the bulk subsoil community. The bacterial core microbiome in this soil was estimated and only covers 7.6% of the bacterial sequencing reads but includes both oligotrophic and copiotrophic bacteria. Instead, the archaeal core microbiome includes 56% of the overall archaeal diversity and comprises only the ammonium oxidizing Nitrososphaera. Thus, the spatial variability of nutrient quality and quantity strongly shapes the bacterial community composition and their interaction in subsoil, whereas archaea are a stable backbone of the soil prokaryotes.

  8. Tip moth control and loblolly pine growth in intensive pine culture: four year results

    Science.gov (United States)

    David L. Kulhavy; Jimmie L. Yeiser; L. Allen Smith

    2006-01-01

    Twenty-two treatments replicated four times were applied to planted loblolly pine, Pinus taeda L., on bedded industrial forest land in east Texas for measurement of growth impact of Nantucket pine tip moth (NPTM), Rhyacionia frustrana Comstock, and effects on pine growth over 2 years. Treatments were combinations of Velpar®,...

  9. El Fenómeno de Consumo y el Consumo en Marketing

    Directory of Open Access Journals (Sweden)

    Dagoberto Páramo Morales

    2004-01-01

    Full Text Available En este artículo se presentan las principales características que tipifican el fenómeno de consumo en las sociedades contemporáneas. Para lograrlo, primero se revisan algunas aproximaciones conceptuales del consumo, visto como fenómeno social, asociándolo con el simbolismo de consumo, los rituales, las posesiones y el materialismo como motores propulsores de la concepción y práctica del marketing de hoy.

  10. The Austrian x red pine hybrid

    Science.gov (United States)

    W. B. Critchfield

    1963-01-01

    The genetic improvement of red pine (Pinus resinosa Ait.) presents tree breeders with one of their most difficult problems. Not only is this valuable species remarkably uniform, but until 1955 it resisted all attempts to cross it with other pines. In that year red pine and Austrian pine (P. nigra var. austriaca [...

  11. The annual carbon budget for fen and forest in a wetland at Arctic treeline

    Energy Technology Data Exchange (ETDEWEB)

    Rouse, W. R. [McMaster Univ., School of Geography and Geology, Hamilton, ON (Canada); Bello, R. L.; D' Souza, A. [York Univ., Dept. of Geography, Toronto, ON (Canada); Griffis, T. J. [Minnesota Univ., Dept. of Soil, Water and Climate, St. Paul, MN (United States); LaFleur, P. M. [Trent Univ., Dept. of Geography, Peterborough, ON (Canada)

    2002-09-01

    This study of a wetland system at the Arctic treeline compares two carbon budget estimates, one derived from long-term growth rates of organic soil and the other based on shorter-term flux measurements. Result showed that while there was a small loss of carbon from the ecosystem in the case of tundra fen over a period of fifty-three years, the adjacent open subarctic forest showed large gains in atmospheric carbon dioxide during the same period. These longer-term data were supported by shorter-term flux measurements, which also showed carbon loss by the fen and carbon uptake by the forest. The shorter term data indicate that the carbon loss from the fen during this period was attributable to one particularly dry year. The different rates of carbon exchange appear to be controlled by two primary factors. The first is the enhanced development in the fen of a photosynthesis-inhibiting hummock-hollow landscape, while the second is related to warmer and drier average growing season conditions, which inhibit carbon dioxide uptake in the fen and enhances it in the forest. 24 refs., 4 tabs., 3 figs.

  12. Mountain Pine Beetle Dynamics and Reproductive Success in Post-Fire Lodgepole and Ponderosa Pine Forests in Northeastern Utah.

    Directory of Open Access Journals (Sweden)

    Andrew P Lerch

    Full Text Available Fire injury can increase tree susceptibility to some bark beetles (Curculionidae, Scolytinae, but whether wildfires can trigger outbreaks of species such as mountain pine beetle (Dendroctonus ponderosae Hopkins is not well understood. We monitored 1173 lodgepole (Pinus contorta var. latifolia Doug. and 599 ponderosa (Pinus ponderosa Doug. ex Law pines for three years post-wildfire in the Uinta Mountains of northeastern Utah in an area with locally endemic mountain pine beetle. We examined how the degree and type of fire injury influenced beetle attacks, brood production, and subsequent tree mortality, and related these to beetle population changes over time. Mountain pine beetle population levels were high the first two post-fire years in lodgepole pine, and then declined. In ponderosa pine, populations declined each year after initial post-fire sampling. Compared to trees with strip or failed attacks, mass attacks occurred on trees with greater fire injury, in both species. Overall, a higher degree of damage to crowns and boles was associated with higher attack rates in ponderosa pines, but additional injury was more likely to decrease attack rates in lodgepole pines. In lodgepole pine, attacks were initially concentrated on fire-injured trees, but during subsequent years beetles attacked substantial numbers of uninjured trees. In ponderosa pine, attacks were primarily on injured trees each year, although these stands were more heavily burned and had few uninjured trees. In total, 46% of all lodgepole and 56% of ponderosa pines underwent some degree of attack. Adult brood emergence within caged bole sections decreased with increasing bole char in lodgepole pine but increased in ponderosa pine, however these relationships did not scale to whole trees. Mountain pine beetle populations in both tree species four years post-fire were substantially lower than the year after fire, and wildfire did not result in population outbreaks.

  13. Mountain Pine Beetle Dynamics and Reproductive Success in Post-Fire Lodgepole and Ponderosa Pine Forests in Northeastern Utah.

    Science.gov (United States)

    Lerch, Andrew P; Pfammatter, Jesse A; Bentz, Barbara J; Raffa, Kenneth F

    2016-01-01

    Fire injury can increase tree susceptibility to some bark beetles (Curculionidae, Scolytinae), but whether wildfires can trigger outbreaks of species such as mountain pine beetle (Dendroctonus ponderosae Hopkins) is not well understood. We monitored 1173 lodgepole (Pinus contorta var. latifolia Doug.) and 599 ponderosa (Pinus ponderosa Doug. ex Law) pines for three years post-wildfire in the Uinta Mountains of northeastern Utah in an area with locally endemic mountain pine beetle. We examined how the degree and type of fire injury influenced beetle attacks, brood production, and subsequent tree mortality, and related these to beetle population changes over time. Mountain pine beetle population levels were high the first two post-fire years in lodgepole pine, and then declined. In ponderosa pine, populations declined each year after initial post-fire sampling. Compared to trees with strip or failed attacks, mass attacks occurred on trees with greater fire injury, in both species. Overall, a higher degree of damage to crowns and boles was associated with higher attack rates in ponderosa pines, but additional injury was more likely to decrease attack rates in lodgepole pines. In lodgepole pine, attacks were initially concentrated on fire-injured trees, but during subsequent years beetles attacked substantial numbers of uninjured trees. In ponderosa pine, attacks were primarily on injured trees each year, although these stands were more heavily burned and had few uninjured trees. In total, 46% of all lodgepole and 56% of ponderosa pines underwent some degree of attack. Adult brood emergence within caged bole sections decreased with increasing bole char in lodgepole pine but increased in ponderosa pine, however these relationships did not scale to whole trees. Mountain pine beetle populations in both tree species four years post-fire were substantially lower than the year after fire, and wildfire did not result in population outbreaks.

  14. Missed cleavage opportunities by FEN1 lead to Okazaki fragment maturation via the long-flap pathway

    KAUST Repository

    Zaher, Manal S.; Rashid, Fahad; Song, Bo; Joudeh, Luay I; Sobhy, Mohamed Abdelmaboud; Tehseen, Muhammad; Hingorani, Manju M; Hamdan, Samir

    2018-01-01

    RNA-DNA hybrid primers synthesized by low fidelity DNA polymerase α to initiate eukaryotic lagging strand synthesis must be removed efficiently during Okazaki fragment (OF) maturation to complete DNA replication. In this process, each OF primer is displaced and the resulting 5'-single-stranded flap is cleaved by structure-specific 5'-nucleases, mainly Flap Endonuclease 1 (FEN1), to generate a ligatable nick. At least two models have been proposed to describe primer removal, namely short- and long-flap pathways that involve FEN1 or FEN1 along with Replication Protein A (RPA) and Dna2 helicase/nuclease, respectively. We addressed the question of pathway choice by studying the kinetic mechanism of FEN1 action on short- and long-flap DNA substrates. Using single molecule FRET and rapid quench-flow bulk cleavage assays, we showed that unlike short-flap substrates, which are bound, bent and cleaved within the first encounter between FEN1 and DNA, long-flap substrates can escape cleavage even after DNA binding and bending. Notably, FEN1 can access both substrates in the presence of RPA, but bending and cleavage of long-flap DNA is specifically inhibited. We propose that FEN1 attempts to process both short and long flaps, but occasional missed cleavage of the latter allows RPA binding and triggers the long-flap OF maturation pathway.

  15. Missed cleavage opportunities by FEN1 lead to Okazaki fragment maturation via the long-flap pathway

    KAUST Repository

    Zaher, Manal S.

    2018-01-27

    RNA-DNA hybrid primers synthesized by low fidelity DNA polymerase α to initiate eukaryotic lagging strand synthesis must be removed efficiently during Okazaki fragment (OF) maturation to complete DNA replication. In this process, each OF primer is displaced and the resulting 5\\'-single-stranded flap is cleaved by structure-specific 5\\'-nucleases, mainly Flap Endonuclease 1 (FEN1), to generate a ligatable nick. At least two models have been proposed to describe primer removal, namely short- and long-flap pathways that involve FEN1 or FEN1 along with Replication Protein A (RPA) and Dna2 helicase/nuclease, respectively. We addressed the question of pathway choice by studying the kinetic mechanism of FEN1 action on short- and long-flap DNA substrates. Using single molecule FRET and rapid quench-flow bulk cleavage assays, we showed that unlike short-flap substrates, which are bound, bent and cleaved within the first encounter between FEN1 and DNA, long-flap substrates can escape cleavage even after DNA binding and bending. Notably, FEN1 can access both substrates in the presence of RPA, but bending and cleavage of long-flap DNA is specifically inhibited. We propose that FEN1 attempts to process both short and long flaps, but occasional missed cleavage of the latter allows RPA binding and triggers the long-flap OF maturation pathway.

  16. Southern Pine Beetle Information System (SPBIS)

    Science.gov (United States)

    Valli Peacher

    2011-01-01

    The southern pine beetle (SPB) is the most destructive forest insect in the South. The SPB attacks all species of southern pine, but loblolly and shortleaf are most susceptible. The Southern Pine Beetle Information System (SPBIS) is the computerized database used by the national forests in the Southern Region for tracking individual southern pine beetle infestations....

  17. Seagrass as major source of transparent exopolymer particles in the oligotrophic Mediterranean coast

    KAUST Repository

    Iuculano, Francesca

    2017-01-09

    The role of seagrass, Posidonia oceanica, meadows as a source of transparent exopolymer particles (TEP) to Mediterranean coastal waters was tested by comparing the TEP dynamics in two adjacent coastal waters in the oligotrophic NW Mediterranean Sea, one characterized by oligotrophic open-sea waters and the other accumulating seagrass leaf litter, together with an experimental examination of TEP release by seagrass litter. TEP concentrations ranged from 4.6 µg XG Eq L−1 to 90.6 µg XG Eq L−1, with mean (±SE) values of 38.7 (±2.02) µg XG Eq L−1 in the site devoid of seagrass litter, whereas the coastal beach site accumulating leaf litter had > 10-fold mean TEP concentrations of 487.02 (±72.8) µg XG Eq L−1 . Experimental evaluation confirmed high rates of TEP production by P. oceanica litter, allowing calculations of the associated TEP yield. We demonstrated that P. oceanica is an important source of TEP to the Mediterranean Sea, contributing an estimated 0.10 Tg C as TEP annually. TEP release by P. oceanica seagrass explains the elevated TEP concentration relative to the low chlorophyll a concentration in the Mediterranean Sea.

  18. Sea surface temperature control of taxon specific phytoplankton production along an oligotrophic gradient in the Mediterranean Sea

    NARCIS (Netherlands)

    van de Poll, W.H.V.; Boute, P.G.; Rozema, P.D.; Buma, A.; Kulk, G.; Rijkenberg, M.J.

    2015-01-01

    The current study aimed to assess changes in phytoplankton composition and productivity along an oligotrophic gradient in relation to changes in sea surface temperature (SST). Phytoplankton pigments, nutrients, and physical water column properties were studied along a longitudinal transect in the

  19. Mountain pine beetle in lodgepole pine: mortality and fire implications (Project INT-F-07-03)

    Science.gov (United States)

    Jennifer G. Klutsch; Daniel R. West; Mike A Battaglia; Sheryl L. Costello; José F. Negrón; Charles C. Rhoades; John Popp; Rick Caissie

    2013-01-01

    Mountain pine beetle (Dendroctonus ponderosae Hopkins) has infested over 2 million acres of lodgepole pine (Pinus contorta Dougl. ex Loud.) forest since an outbreak began approximately in 2000 in north central Colorado. The tree mortality from mountain pine beetle outbreaks has the potential to alter stand composition and stand...

  20. Comparative studies of the nitrogen metabolism of phytoplankton and periphyton in oligotrophic lakes

    International Nuclear Information System (INIS)

    Axler, R.P.; Goldman, C.R.; Reuter, J.E.; Loeb, S.L.; Priscu, J.C.; Carlton, R.G.

    1983-01-01

    This report presents the preliminary data of limnological research at the meso-oligotrophic Castle Lake, CA and at the ultratrophic Lake Tahoe, CA-NEV, USA, during 1980 to 1981. The areas of study were effects of nutrients enrichment and deficiency on primary producers; nitrogen cycling and nitrogen metabolism of benthic and planktonic algae and whole-epilimnion enrichment with ammonium nitrate. Tracer techniques using 14 C- and 15 N-labelled compounds were employed in the study

  1. Determination of the 54Fe(n, 2n)53gFe and 54Fe(n, 2n)53mFe cross sections averaged over a 235U fission neutron spectrum

    International Nuclear Information System (INIS)

    Ribeiro Guevara, S.; Arribere, M.; Kestelman, A.J.

    2002-01-01

    The reaction cross sections averaged over a 235 U fission neutron spectrum have been measured for the 54 Fe(n, 2n) 53g Fe and 54 Fe(n, 2n) 53m Fe threshold reactions. The values found are, respectively: (1.14 ± 0.13) μb, and (0.52 ± 0.16) μb. The measured cross sections are referred to the (111± 3) mb standard cross section of the 58 Ni(n, p) 58m+g Co reaction. The (81.7 ± 2.2) mb standard cross section value for the 54 Fe(n, p) 54 Mn reaction, was also used as a monitor to check the results obtained with the Ni standard, leading to an excellent agreement. (author)

  2. Microbial activity and community structure in two drained fen soils in the Ljubljana Marsh

    NARCIS (Netherlands)

    Kraigher, Barbara; Stres, Blaz; Hacin, Janez; Ausec, Luka; Mahne, Ivan; van Elsas, Jan D.; Mandic-Mulec, Ines

    Fen peatlands are specific wetland ecosystems containing high soil organic carbon (SOC). There is a general lack of knowledge about the microbial communities that abound in these systems. We examined the microbial activity and community structure in two fen soils differing in SOC content sampled

  3. Resilience of ponderosa and lodgepole pine forests to mountain pine beetle disturbance and limited regeneration

    Science.gov (United States)

    Briggs, Jenny S.; Hawbaker, Todd J.; Vandendriesche, Don

    2015-01-01

    After causing widespread mortality in lodgepole pine forests in North America, the mountain pine beetle (MPB) has recently also affected ponderosa pine, an alternate host species that may have different levels of resilience to this disturbance. We collected field data in ponderosa pine- and lodgepole pine-dominated forests attacked by MPB in Colorado and then simulated stand growth over 200 years using the Forest Vegetation Simulator. We compared scenarios of no disturbance with scenarios of MPB-caused mortality, both with and without regeneration. Results indicated that basal area and tree density recovered to predisturbance levels relatively rapidly (within 1‐8 decades) in both forest types. However, convergence of the disturbed conditions with simulated undisturbed conditions took longer (12‐20+ decades) and was delayed by the absence of regeneration. In MPB-affected ponderosa pine forests without regeneration, basal area did not converge with undisturbed conditions within 200 years, implying lower resilience in this ecosystem. Surface fuels accumulated rapidly in both forest types after MPB-induced mortality, remaining high for 3‐6 decades in simulations. Our results suggest that future patterns of succession, regeneration, fuel loading, climate, and disturbance interactions over long time periods should be considered in management strategies addressing MPB effects in either forest type, but particularly in ponderosa pine.

  4. Phosphorus cycling and partitioning in an oligotrophic Everglades wetland ecosystem: A radioisotope tracing study

    Science.gov (United States)

    Noe, G.B.; Scinto, L.J.; Taylor, J.; Childers, D.L.; Jones, R.D.

    2003-01-01

    1. Our goal was to quantify short-term phosphorus (P) partitioning and identify the ecosystem components important to P cycling in wetland ecosystems. To do this, we added P radiotracer to oligotrophic, P-limited Everglades marshes. 32PO4 was added to the water column in six 1-m2 enclosed mesocosms located in long-hydroperiod marshes of Shark River Slough, Everglades National Park. Ecosystem components were then repeatedly sampled over 18 days. 2. Water column particulates (>0.45 ??m) incorporated radiotracer within the first minute after dosing and stored 95-99% of total water column 32P activity throughout the study. Soluble (<0.45 ??m) 32P in the water column, in contrast, was always <5% of the 32P in surface water. Periphyton, both floating and attached to emergent macrophytes, had the highest specific activity of 32P (Bq g-131P) among the different ecosystem components. Fish and aquatic macroinvertebrates also had high affinity for P, whereas emergent macrophytes, soil and flocculent detrital organic matter (floc) had the lowest specific activities of radiotracer. 3. Within the calcareous, floating periphyton mats, 81% of the initial 32P uptake was associated with Ca, but most of this 32P entered and remained within the organic pool (Ca-associated = 14% of total) after 1 day. In the floc layer, 32P rapidly entered the microbial pool and the labile fraction was negligible for most of the study. 4. Budgeting of the radiotracer indicated that 32P moved from particulates in the water column to periphyton and floc and then to the floc and soil over the course of the 18 days incubations. Floc (35% of total) and soil (27%) dominated 32P storage after 18 days, with floating periphyton (12%) and surface water (10%) holding smaller proportions of total ecosystem 32P. 5. To summarise, oligotrophic Everglades marshes exhibited rapid uptake and retention of labile 32P. Components dominated by microbes appear to control short-term P cycling in this oligotrophic ecosystem.

  5. Insect biodiversity reduction of pine woods in southern Greece caused by the pine scale (Marchalina hellenica)

    Energy Technology Data Exchange (ETDEWEB)

    Petrakis, P. V.; Spanos, K.; Feest, A.

    2011-07-01

    This paper deals with the impact of the pine scale (Marchalina hellenica Gennadius, Hemiptera, Sternorrhyncha, Margarodidae) on the insect biodiversity of pinewoods in Attica, Greece. The comparison of biodiversities was done by estimating the biodiversity by the Ewens-Caswells V statistic in a set of nine sites each containing two linetransects. Transects pairs went through free and infested pine woods from the pine scale and each one had several tenth hectare plots on both sides. The ecosystem temperature (= disorder) of the sites was computed and found high, together with the idiosyncratic temperatures (= susceptibility to extinction) of the 158 species in order to detect local extinctions. The indicator values of insect species were computed on the basis of the relative cover of each plant species. The main findings of this study are (1) the reduction of insect species biodiversity because of the introduction of the pine scale, (2) the moderate increase of disorder in pine scale infested sites,(3) many insect species can characterize site groups but none of them can distinguish infested from pine scale free sites. The introduction of pine scale in pine woods disturbs their insect fauna before its influence to the floristic composition and the associated vegetation structure appears. The causes behind this reduction of biodiversity and the anthropogenic influences are discussed. (Author) 64 refs.

  6. High bacterial diversity in epilithic biofilms of oligotrophic mountain lakes.

    Science.gov (United States)

    Bartrons, Mireia; Catalan, Jordi; Casamayor, Emilio O

    2012-11-01

    Benthic microbial biofilms attached to rocks (epilithic) are major sites of carbon cycling and can dominate ecosystem primary production in oligotrophic lakes. We studied the bacterial community composition of littoral epilithic biofilms in five connected oligotrophic high mountain lakes located at different altitudes by genetic fingerprinting and clone libraries of the 16S rRNA gene. Different intra-lake samples were analyzed, and consistent changes in community structure (chlorophyll a and organic matter contents, and bacterial community composition) were observed along the altitudinal gradient, particularly related with the location of the lake above or below the treeline. Epilithic biofilm genetic fingerprints were both more diverse among lakes than within lakes and significantly different between montane (below the tree line) and alpine lakes (above the tree line). The genetic richness in the epilithic biofilm was much higher than in the plankton of the same lacustrine area studied in previous works, with significantly idiosyncratic phylogenetic composition (specifically distinct from lake plankton or mountain soils). Data suggest the coexistence of aerobic, anaerobic, phototrophic, and chemotrophic microorganisms in the biofilm, Bacteroidetes and Cyanobacteria being the most important bacterial taxa, followed by Alpha-, Beta-, Gamma-, and Deltaproteobacteria, Chlorobi, Planctomycetes, and Verrucomicrobia. The degree of novelty was especially high for epilithic Bacteroidetes, and up to 50 % of the sequences formed monophyletic clusters distantly related to any previously reported sequence. More than 35 % of the total sequences matched at <95 % identity to any previously reported 16S rRNA gene, indicating that alpine epilithic biofilms are unexplored habitats that contain a substantial degree of novelty within a short geographical distance. Further research is needed to determine whether these communities are involved in more biogeochemical pathways than

  7. Influence of hardwood midstory and pine species on pine bole arthropods

    Science.gov (United States)

    Christopher S. Collins; Richard N. Conner; Daniel Saenz

    2002-01-01

    Arthropod density on the boles of loblolly pines (Pinus taeda) was compared between a stand with and stand without hardwood midstory and between a stand of loblolly and shortleaf pines (P. echinata) in the Stephen E Austin Experimental Forest, Nacogdoches Co., Texas, USA from September 1993 through July 1994. Arthropod density was...

  8. Deep silicon maxima in the stratified oligotrophic Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    Y. Crombet

    2011-02-01

    Full Text Available The silicon biogeochemical cycle has been studied in the Mediterranean Sea during late summer/early autumn 1999 and summer 2008. The distribution of nutrients, particulate carbon and silicon, fucoxanthin (Fuco, and total chlorophyll-a (TChl-a were investigated along an eastward gradient of oligotrophy during two cruises (PROSOPE and BOUM encompassing the entire Mediterranean Sea during the stratified period. At both seasons, surface waters were depleted in nutrients and the nutriclines gradually deepened towards the East, the phosphacline being the deepest in the easternmost Levantine basin. Following the nutriclines, parallel deep maxima of biogenic silica (DSM, fucoxanthin (DFM and TChl-a (DCM were evidenced during both seasons with maximal concentrations of 0.45 μmol L−1 for BSi, 0.26 μg L−1 for Fuco, and 1.70 μg L−1 for TChl-a, all measured during summer. Contrary to the DCM which was a persistent feature in the Mediterranean Sea, the DSM and DFMs were observed in discrete areas of the Alboran Sea, the Algero-Provencal basin, the Ionian sea and the Levantine basin, indicating that diatoms were able to grow at depth and dominate the DCM under specific conditions. Diatom assemblages were dominated by Chaetoceros spp., Leptocylindrus spp., Pseudonitzschia spp. and the association between large centric diatoms (Hemiaulus hauckii and Rhizosolenia styliformis and the cyanobacterium Richelia intracellularis was observed at nearly all sites. The diatom's ability to grow at depth is commonly observed in other oligotrophic regions and could play a major role in ecosystem productivity and carbon export to depth. Contrary to the common view that Si and siliceous phytoplankton are not major components of the Mediterranean biogeochemistry, we suggest here that diatoms, by persisting at depth during the stratified period, could contribute to a

  9. Suspended marine particulate proteins in coastal and oligotrophic waters

    Science.gov (United States)

    Bridoux, Maxime C.; Neibauer, Jaqui; Ingalls, Anitra E.; Nunn, Brook L.; Keil, Richard G.

    2015-03-01

    Metaproteomic analyses were performed on suspended sediments collected in one coastal environment (Washington margin, Pacific Ocean, n = 5) and two oligotrophic environments (Atlantic Ocean near BATS, n = 5, and Pacific Ocean near HOTS, n = 5). Using a database of 2.3 million marine proteins developed using the NCBI database, 443 unique peptides were detected from which 363 unique proteins were identified. Samples from the euphotic zone contained on average 2-3x more identifiable proteins than deeper waters (150-1500 m) and these proteins were predominately from photosynthetic organisms. Diatom peptides dominate the spectra of the Washington margin while peptides from cyanobacteria, such as Synechococcus sp. dominated the spectra of both oligotrophic sites. Despite differences in the exact proteins identified at each location, there is good agreement for protein function and cellular location. Proteins in surface waters code for a variety of cellular functions including photosynthesis (24% of detected proteins), energy production (10%), membrane production (9%) and genetic coding and reading (9%), and are split 60-40 between membrane proteins and intracellular cytoplasmic proteins. Sargasso Sea surface waters contain a suite of peptides consistent with proteins involved in circadian rhythms that promote both C and N fixation at night. At depth in the Sargasso Sea, both muscle-derived myosin protein and the muscle-hydrolyzing proteases deseasin MCP-01 and metalloprotease Mcp02 from γ-proteobacteria were observed. Deeper waters contain peptides predominately sourced from γ-proteobacteria (37% of detected proteins) and α-proteobacteria (26%), although peptides from membrane and photosynthetic proteins attributable to phytoplankton were still observed (13%). Relative to surface values, detection frequencies for bacterial membrane proteins and extracellular enzymes rose from 9 to 16 and 2 to 4% respectively below the thermocline and the overall balance between

  10. Population densities and tree diameter effects associated with verbenone treatments to reduce mountain pine beetle-caused mortality of lodgepole pine.

    Science.gov (United States)

    Progar, R A; Blackford, D C; Cluck, D R; Costello, S; Dunning, L B; Eager, T; Jorgensen, C L; Munson, A S; Steed, B; Rinella, M J

    2013-02-01

    Mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae: Scolytinae), is among the primary causes of mature lodgepole pine, Pinus contorta variety latifolia mortality. Verbenone is the only antiaggregant semiochemical commercially available for reducing mountain pine beetle infestation of lodgepole pine. The success of verbenone treatments has varied greatly in previous studies because of differences in study duration, beetle population size, tree size, or other factors. To determine the ability of verbenone to protect lodgepole pine over long-term mountain pine beetle outbreaks, we applied verbenone treatments annually for 3 to 7 yr at five western United States sites. At one site, an outbreak did not develop; at two sites, verbenone reduced lodgepole pine mortality in medium and large diameter at breast height trees, and at the remaining two sites verbenone was ineffective at reducing beetle infestation. Verbenone reduced mountain pine beetle infestation of lodgepole pine trees in treated areas when populations built gradually or when outbreaks in surrounding untreated forests were of moderate severity. Verbenone did not protect trees when mountain pine beetle populations rapidly increase.

  11. Southern Pine Based on Biorefinery Center

    Energy Technology Data Exchange (ETDEWEB)

    Ragauskas, Arthur J. [Georgia Inst. of Technology, Atlanta, GA (United States); Singh, Preet [Georgia Inst. of Technology, Atlanta, GA (United States)

    2013-12-20

    This program seeks to develop an integrated southern pine wood to biofuels/biomaterials processing facility on the Recipient’s campus, that will test advanced integrated wood processing technologies at the laboratory scale, including: The generation of the bioethanol from pines residues and hemicelluloses extracted from pine woodchips; The conversion of extracted woodchips to linerboard and bleach grade pulps; and the efficient conversion of pine residues, bark and kraft cooking liquor into a useful pyrolysis oil.

  12. Hybridization Leads to Loss of Genetic Integrity in Shortleaf Pine: Unexpected Consequences of Pine Management and Fire Suppression

    Science.gov (United States)

    Charles G. Tauer; John F. Stewart; Rodney E. Will; Curtis J. Lilly; James M. Guldin; C. Dana Nelson

    2012-01-01

    Hybridization between shortleaf pine and loblolly pine is causing loss of genetic integrity (the tendency of a population to maintain its genotypes over generations) in shortleaf pine, a species already exhibiting dramatic declines due to land-use changes. Recent findings indicate hybridization has increased in shortleaf pine stands from 3% during the 1950s to 45% for...

  13. 1H Nuclear Magnetic Resonance of Lodgepole Pine Wood Chips Affected by the Mountain Pine Beetle

    OpenAIRE

    Todoruk, Tara M.; Hartley, Ian D.; Teymoori, Roshanak; Liang, Jianzhen; Peemoeller, Hartwig

    2010-01-01

    In this study, wood-water interactions of mountain pine beetle affected lodgepole pine were found to vary with time since death. Based on an analysis of magnetization components and spin-spin relaxation times from 1H NMR, it was determined that the mountain pine beetle attack does not affect the crystalline structure of the wood. Both the amorphous structure and the water components vary with time since death, which could be due to the fungi present after a mountain pine beetle attack, as wel...

  14. Strong partial resistance to white pine blister rust in sugar pine

    Science.gov (United States)

    Bohun B. Kinloch, Jr.; Deems Burton; Dean A. Davis; Robert D. Westfall; Joan Dunlap; Detlev Vogler

    2012-01-01

    Quantitative resistance to white pine blister rust in 128 controlled- and open-pollinated sugar pine families was evaluated in a “disease garden”, where alternate host Ribes bushes were interplanted among test progenies. Overall infection was severe (88%), but with great variation among and within families: a 30-fold range in numbers of infections...

  15. From groundwater abstraction to vegetative response in fen ecosystems

    DEFF Research Database (Denmark)

    Johansen, Ole Munch; Jensen, Jacob Birk; Pedersen, Morten Lauge

    2014-01-01

    Hydrological effects of groundwater abstraction near a Danish river valley have been assessed by integrated hydrological modelling. The study site contains groundwater-dependent terrestrial ecosystems in terms of fen and spring habitats that are highly dependent on regional and local scale...... hydrology. Fens are rare and threatened worldwide due to pressures from agriculture, to lack of appropriate management and to altered catchment hydrology. A solid foundation for hydrological modelling was established based on intensive monitoring at the site, combined with full-scale pumping tests...... in the area. A regional groundwater model was used to describe the dynamics in groundwater recharge and the large-scale discharge to streams. A local grid refinement approach was then applied in a detailed assessment of damage in order to balance the computational effort and the need for a high spatial...

  16. Small molecule inhibitors uncover synthetic genetic interactions of human flap endonuclease 1 (FEN1 with DNA damage response genes.

    Directory of Open Access Journals (Sweden)

    Thomas A Ward

    Full Text Available Flap endonuclease 1 (FEN1 is a structure selective endonuclease required for proficient DNA replication and the repair of DNA damage. Cellularly active inhibitors of this enzyme have previously been shown to induce a DNA damage response and, ultimately, cell death. High-throughput screens of human cancer cell-lines identify colorectal and gastric cell-lines with microsatellite instability (MSI as enriched for cellular sensitivity to N-hydroxyurea series inhibitors of FEN1, but not the PARP inhibitor olaparib or other inhibitors of the DNA damage response. This sensitivity is due to a synthetic lethal interaction between FEN1 and MRE11A, which is often mutated in MSI cancers through instabilities at a poly(T microsatellite repeat. Disruption of ATM is similarly synthetic lethal with FEN1 inhibition, suggesting that disruption of FEN1 function leads to the accumulation of DNA double-strand breaks. These are likely a result of the accumulation of aberrant replication forks, that accumulate as a consequence of a failure in Okazaki fragment maturation, as inhibition of FEN1 is toxic in cells disrupted for the Fanconi anemia pathway and post-replication repair. Furthermore, RAD51 foci accumulate as a consequence of FEN1 inhibition and the toxicity of FEN1 inhibitors increases in cells disrupted for the homologous recombination pathway, suggesting a role for homologous recombination in the resolution of damage induced by FEN1 inhibition. Finally, FEN1 appears to be required for the repair of damage induced by olaparib and cisplatin within the Fanconi anemia pathway, and may play a role in the repair of damage associated with its own disruption.

  17. Ponderosa pine mortality resulting from a mountain pine beetle outbreak

    Science.gov (United States)

    William F. McCambridge; Frank G. Hawksworth; Carleton B. Edminster; John G. Laut

    1982-01-01

    From 1965 to 1978, mountain pine beetles killed 25% of the pines taller than 4.5 feet in a study area in north-central Colorado. Average basal area was reduced from 92 to 58 square feet per acre. Mortality increased with tree diameter up to about 9 inches d.b.h. Larger trees appeared to be killed at random. Mortality was directly related to number of trees per acre and...

  18. Selection for resistance to white pine blister rust affects the abiotic stress tolerances of limber pine

    Science.gov (United States)

    Patrick J. Vogan; Anna W. Schoettle

    2015-01-01

    Limber pine (Pinus flexilis) mortality is increasing across the West as a result of the combined stresses of white pine blister rust (Cronartium ribicola; WPBR), mountain pine beetle (Dendroctonus ponderosae), and dwarf mistletoe (Arceuthobium cyanocarpum) in a changing climate. With the continued spread of WPBR, extensive mortality will continue with strong selection...

  19. Mountain pine beetle attack associated with low levels of 4-allylanisole in ponderosa pine.

    Science.gov (United States)

    Emerick, Jay J; Snyder, Aaron I; Bower, Nathan W; Snyder, Marc A

    2008-08-01

    Mountain pine beetle (Dendroctonus ponderosae) is the most important insect pest in southern Rocky Mountain ponderosa pine (Pinus ponderosa) forests. Tree mortality is hastened by the various fungal pathogens that are symbiotic with the beetles. The phenylpropanoid 4-allylanisole is an antifungal and semiochemical for some pine beetle species. We analyzed 4-allylanisole and monoterpene profiles in the xylem oleoresin from a total of 107 trees at six sites from two chemotypes of ponderosa pine found in Colorado and New Mexico using gas chromatography-mass spectroscopy (GC-MS). Although monoterpene profiles were essentially the same in attacked and nonattacked trees, significantly lower levels of 4-allylanisole were found in attacked trees compared with trees that showed no evidence of attack for both chemotypes.

  20. Southern pine beetle in loblolly pine: simulating within stand interactions using the process model SPBLOBTHIN

    Science.gov (United States)

    Brian Strom; J. R. Meeker; J. Bishir; James Roberds; X. Wan

    2016-01-01

    Pine stand density is a key determinant of damage resulting from attacks by the southern pine beetle (SPB, Dendroctonus frontalis Zimm.). High-density stands of maturing loblolly pine (Pinus taeda L.) are at high risk for losses to SPB, and reducing stand density is the primary tool available to forest managers for preventing and mitigating damage. Field studies are...

  1. Phytoplankton biovolume is independent from the slope of the size spectrum in the oligotrophic atlantic ocean

    KAUST Repository

    Moreno-Ostos, Enrique

    2015-08-06

    Modelling the size-abundance spectrum of phytoplankton has proven to be a very useful tool for the analysis of physical-biological coupling and the vertical flux of carbon in oceanic ecosystems at different scales. A frequent observation relates high phytoplankton biovolume in productive regions with flatter spectrum slope and the opposite in oligotrophic ecosystems. Rather than this, the relationship between high biovolume phytoplankton assemblages and flatter size-abundance spectra does not correspond with measurements of the phytoplankton community in the Atlantic Ocean open waters. As part of the Malaspina Circunnavegation Expedition, sixty seven sampling stations within the Atlantic Ocean covering six oceanographic provinces, at different seasons, produced a complete set of phytoplankton size-spectra whose slope and biovolume did not show any obvious interrelation. In these oligotrophic sites, small (procaryotes) and medium-size (nanoplankton) cells are responsible for the most part of biovolume, and their response to environmental conditions does not apply to changes in the size-abundance spectrum slope as expected in richer, large-cell dominated ecosystems.

  2. Decomposition rate of peat-forming plants in the oligotrophic peatland at the first stages of destruction

    Science.gov (United States)

    Nikonova, L. G.; Golovatskaya, E. A.; Terechshenko, N. N.

    2018-03-01

    The research presents quantitative estimates of the decomposition rate of plant residues at the initial stages of the decay of two plant species (Eriophorum vaginatum and Sphagnum fuscum) in a peat deposit of the oligotrophic bog in the southern taiga subzone of Western Siberia. We also studied a change in the content of total carbon and nitrogen in plant residues and the activity of microflora in the initial stages of decomposition. At the initial stage of the transformation process of peat-forming plants the losses of mass of Sph. fuscum is 2.5 times lower then E. vaginatum. The most active mass losses, as well as a decrease in the total carbon content, is observed after four months of the experiment. The most active carbon removal is characteristic for E. vaginatum. During the decomposition of plant residues, the nitrogen content decreases, and the most intense nitrogen losses were characteristic for Sph. fuscum. The microorganisms assimilating organic and mineral nitrogen are more active in August, the oligotrophic and cellulolytic microorganisms – in July.

  3. Regeneration of Rocky Mountain bristlecone pine (Pinus aristata) and limber pine (Pinus flexilis) three decades after stand-replacing fires

    Science.gov (United States)

    Jonathan D. Coop; Anna W. Schoettle

    2009-01-01

    Rocky Mountain bristlecone pine (Pinus aristata) and limber pine (Pinus flexilis) are important highelevation pines of the southern Rockies that are forecast to decline due to the recent spread of white pine blister rust (Cronartium ribicola) into this region. Proactive management strategies to promote the evolution of rust resistance and maintain ecosystem function...

  4. Monitoring white pine blister rust infection and mortality in whitebark pine in the Greater Yellowstone ecosystem

    Science.gov (United States)

    Cathie Jean; Erin Shanahan; Rob Daley; Gregg DeNitto; Dan Reinhart; Chuck Schwartz

    2011-01-01

    There is a critical need for information on the status and trend of whitebark pine (Pinus albicaulis) in the Greater Yellowstone Ecosystem (GYE). Concerns over the combined effects of white pine blister rust (WPBR, Cronartium ribicola), mountain pine beetle (MPB, Dendroctonus ponderosae), and climate change prompted an interagency working group to design and implement...

  5. Carbon sequestration and natural longleaf pine ecosystems

    Science.gov (United States)

    Ralph S. Meldahl; John S. Kush

    2006-01-01

    A fire-maintained longleaf pine (Pinus palustris Mill.) ecosystem may offer the best option for carbon (C) sequestration among the southern pines. Longleaf is the longest living of the southern pines, and products from longleaf pine will sequester C longer than most since they are likely to be solid wood products such as structural lumber and poles....

  6. Literatura expandida: el fenómeno fanfiction en español

    OpenAIRE

    Sanz Martínez, Sandra

    2017-01-01

    En este trabajo se pretende abordar el estudio del llamado “fenómeno fanfiction”, un fenómeno que ha sacudido internet en las últimas décadas y que supone una nueva forma de creación de literatura. La creación de fanfiction supone la realización de una obra, normalmente narrativa, cuyo contenido contiene aspectos de una obra de ficción publicada, siempre sin ánimo de lucro. Departamento de Literatura Española y Teoría de la Literatura y Literatura Comparada Grado en Español: Lengua y...

  7. Status of white pine blister rust and seed collections in california's high-elevation white pine species

    Science.gov (United States)

    J. Dunlap

    2011-01-01

    White pine blister rust (caused by the non-native pathogen Cronartium ribicola) reached northern California about 80 years ago. Over the years its spread southward had been primarily recorded on sugar pine. However, observations on its occurrence had also been reported in several of the higher elevation five-needled white pine species in California. Since the late...

  8. Afforestation in Serbia in the period 1961-2007 with special reference to Austrian pine and Scots pine

    Directory of Open Access Journals (Sweden)

    Ranković Nenad

    2009-01-01

    Full Text Available The significance of afforestation in Serbia is high because only in this way the forest area can be increased and brought to the level which corresponds to the demands of the population. This is also indicated by the content of some documents, such as 'Professional base for the design of the National Forest Action Programme', which emphasises this problem from the very beginning. Special significance is assigned to afforestation with Austrian pine and Scots pine, which are most frequently applied in the afforestation of the most unfavourable terrains. This study analyses the scope of afforestation over the period 1961-2007, the percentage of Austrian pine and Scots pine and the relationship of the afforested areas, and generates the forecasts of the changes in the future period. In this way, the socialeconomic significance of afforestation can be assessed from the aspect of satisfying the objectives of forest policy, and particularly of afforestation with Austrian pine and Scots pine, as the specific tree species.

  9. Population structure of a lodgepole pine (Pinus contorta) and jack pine (P. banksiana) complex as revealed by random amplified polymorphic DNA.

    Science.gov (United States)

    Ye, Terrance Z; Yang, Rong-Cai; Yeh, Francis C

    2002-06-01

    We studied the population structure of a lodgepole (Pinus contorta Dougl.) and jack pine (Pinus banksiana Lamb.) complex in west central Alberta and neighboring areas by assessing random amplified polymorphic DNA (RAPD) variability in 23 lodgepole pine, 9 jack pine, and 8 putative hybrid populations. Of 200 random primers screened, 10 that amplified 39 sharp and reproducible RAPDs were chosen for the study. None of the 39 RAPDs were unique to the parental species. RAPD diversity ranged from 0.085 to 0.190 among populations and averaged 0.143 for lodgepole pine, 0.156 for jack pine, 0.152 for hybrids, and 0.148 for all 40 populations. The estimated population differentiation based on G(ST) was 0.168 for hybrids, 0.162 for lodgepole pine, 0.155 for jack pine, and 0.247 across all 40 populations. Cluster analysis of genetic distances generally separated jack pine from lodgepole pine and hybrids, but no division could be identified that further separated lodgepole pine from hybrids. The observed weak to mild trend of "introgression by distance" in the complex and neighbouring areas was consistent with the view that introgressive hybridization between lodgepole and jack pines within and outside the hybrid zone may have been through secondary contact and primary intergradation, respectively.

  10. Are we over-managing longleaf pine?

    Science.gov (United States)

    John S. Kush; Rebecca J. Barlow; John C. Gilbert

    2012-01-01

    Longleaf pine (Pinus palustris Mill.) is not loblolly (Pinus taeda L.) or slash pine (Pinus elliottii L.). There is the need for a paradigmatic shift in our thinking about longleaf pine. All too often we think of longleaf as an intolerant species, slow-grower, difficult to regenerate, and yet it dominated the pre...

  11. Guidelines for whitebark pine planting prescriptions

    Science.gov (United States)

    Glenda L. Scott; Ward W. McCaughey; Kay Izlar

    2011-01-01

    Whitebark pine (Pinus albicaulis) is a keystone species in high-elevation ecosystems of the western United States. Unfortunately many fragile subalpine ecosystems are losing whitebark pine as a functional community component due to the combined effects of an introduced disease, insects and succession. Planting whitebark pine is one part of a multifaceted restoration...

  12. Effect of experience with pine (Pituophis melanoleucus) and king (Lampropeltis getulus) snake odors on Y-maze behavior of pine snake hatchlings.

    Science.gov (United States)

    Burger, J; Boarman, W; Kurzava, L; Gochfeld, M

    1991-01-01

    The abilities of hatchling pine snakes (Pituophis melanoleucus) and king snakes (Lampropeltis getulus) to discriminate the chemical trails of pine and king snakes was investigated inY-maze experiments. Pine snakes were housed for 17 days either with shavings impregnated with pine snake odor, king snake odor, or no odor to test for the effect of experience on choice. Both pine and king snake hatchlings entered the arm with the pine snake odor and did not enter the arm with the king snake odor. The data support the hypothesis that hatchlings of both species can distinguish conspecific odors from other odors and that our manipulation of previous experience was without effect for pine snake hatchlings.

  13. Microbial ecology in a future climate: effects of temperature and moisture on microbial communities of two boreal fens.

    Science.gov (United States)

    Peltoniemi, Krista; Laiho, Raija; Juottonen, Heli; Kiikkilä, Oili; Mäkiranta, Päivi; Minkkinen, Kari; Pennanen, Taina; Penttilä, Timo; Sarjala, Tytti; Tuittila, Eeva-Stiina; Tuomivirta, Tero; Fritze, Hannu

    2015-07-01

    Impacts of warming with open-top chambers on microbial communities in wet conditions and in conditions resulting from moderate water-level drawdown (WLD) were studied across 0-50 cm depth in northern and southern boreal sedge fens. Warming alone decreased microbial biomass especially in the northern fen. Impact of warming on microbial PLFA and fungal ITS composition was more obvious in the northern fen and linked to moisture regime and sample depth. Fungal-specific PLFA increased in the surface peat in the drier regime and decreased in layers below 10 cm in the wet regime after warming. OTUs representing Tomentella and Lactarius were observed in drier regime and Mortierella in wet regime after warming in the northern fen. The ectomycorrhizal fungi responded only to WLD. Interestingly, warming together with WLD decreased archaeal 16S rRNA copy numbers in general, and fungal ITS copy numbers in the northern fen. Expectedly, many results indicated that microbial response on warming may be linked to the moisture regime. Results indicated that microbial community in the northern fen representing Arctic soils would be more sensitive to environmental changes. The response to future climate change clearly may vary even within a habitat type, exemplified here by boreal sedge fen. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Whitebark pine planting guidelines

    Science.gov (United States)

    Ward McCaughey; Glenda L. Scott; Kay L. Izlar

    2009-01-01

    This article incorporates new information into previous whitebark pine guidelines for planting prescriptions. Earlier 2006 guidelines were developed based on review of general literature, research studies, field observations, and standard US Forest Service survival surveys of high-elevation whitebark pine plantations. A recent study of biotic and abiotic factors...

  15. Comparison of lodgepole and jack pine resin chemistry: implications for range expansion by the mountain pine beetle, Dendroctonus ponderosae (Coleoptera: Curculionidae

    Directory of Open Access Journals (Sweden)

    Erin L. Clark

    2014-02-01

    Full Text Available The mountain pine beetle, Dendroctonus ponderosae, is a significant pest of lodgepole pine in British Columbia (BC, where it has recently reached an unprecedented outbreak level. Although it is native to western North America, the beetle can now be viewed as a native invasive because for the first time in recorded history it has begun to reproduce in native jack pine stands within the North American boreal forest. The ability of jack pine trees to defend themselves against mass attack and their suitability for brood success will play a major role in the success of this insect in a putatively new geographic range and host. Lodgepole and jack pine were sampled along a transect extending from the beetle’s historic range (central BC to the newly invaded area east of the Rocky Mountains in north-central Alberta (AB in Canada for constitutive phloem resin terpene levels. In addition, two populations of lodgepole pine (BC and one population of jack pine (AB were sampled for levels of induced phloem terpenes. Phloem resin terpenes were identified and quantified using gas chromatography. Significant differences were found in constitutive levels of terpenes between the two species of pine. Constitutive α-pinene levels – a precursor in the biosynthesis of components of the aggregation and antiaggregation pheromones of mountain pine beetle – were significantly higher in jack pine. However, lower constitutive levels of compounds known to be toxic to bark beetles, e.g., 3-carene, in jack pine suggests that this species could be poorly defended. Differences in wounding-induced responses for phloem accumulation of five major terpenes were found between the two populations of lodgepole pine and between lodgepole and jack pine. The mountain pine beetle will face a different constitutive and induced phloem resin terpene environment when locating and colonizing jack pine in its new geographic range, and this may play a significant role in the ability of the

  16. Comparison of lodgepole and jack pine resin chemistry: implications for range expansion by the mountain pine beetle, Dendroctonus ponderosae (Coleoptera: Curculionidae).

    Science.gov (United States)

    Clark, Erin L; Pitt, Caitlin; Carroll, Allan L; Lindgren, B Staffan; Huber, Dezene P W

    2014-01-01

    The mountain pine beetle, Dendroctonus ponderosae, is a significant pest of lodgepole pine in British Columbia (BC), where it has recently reached an unprecedented outbreak level. Although it is native to western North America, the beetle can now be viewed as a native invasive because for the first time in recorded history it has begun to reproduce in native jack pine stands within the North American boreal forest. The ability of jack pine trees to defend themselves against mass attack and their suitability for brood success will play a major role in the success of this insect in a putatively new geographic range and host. Lodgepole and jack pine were sampled along a transect extending from the beetle's historic range (central BC) to the newly invaded area east of the Rocky Mountains in north-central Alberta (AB) in Canada for constitutive phloem resin terpene levels. In addition, two populations of lodgepole pine (BC) and one population of jack pine (AB) were sampled for levels of induced phloem terpenes. Phloem resin terpenes were identified and quantified using gas chromatography. Significant differences were found in constitutive levels of terpenes between the two species of pine. Constitutive α-pinene levels - a precursor in the biosynthesis of components of the aggregation and antiaggregation pheromones of mountain pine beetle - were significantly higher in jack pine. However, lower constitutive levels of compounds known to be toxic to bark beetles, e.g., 3-carene, in jack pine suggests that this species could be poorly defended. Differences in wounding-induced responses for phloem accumulation of five major terpenes were found between the two populations of lodgepole pine and between lodgepole and jack pine. The mountain pine beetle will face a different constitutive and induced phloem resin terpene environment when locating and colonizing jack pine in its new geographic range, and this may play a significant role in the ability of the insect to persist in

  17. Formation dynamics of FeN thin films on Cu(100)

    KAUST Repository

    Heryadi, Dodi

    2012-01-01

    To investigate the structural and magnetic properties of thin films of FeN we have performed ab initio molecular dynamics simulations of their formation on Cu(100) substrates. The iron nitride layers exhibit a p4gm(2 × 2) reconstruction and order ferromagnetically in agreement with experiment. We establish the dynamics and time scale of the film formation as a function of the film thickness. The process is split in two phases: formation of almost flat FeN layers and optimization of the distance to the substrate. Our calculated magnetic moments are 1.67 μ B, 2.14 μ B, and 2.21 μ B for one, two, and three monolayers of iron nitride. © 2011 Elsevier B.V. All rights reserved.

  18. Fertilizer responses of longleaf pine trees within a loblolly pine plantation: separating direct effects from competition effects

    Science.gov (United States)

    Peter H Anderson; Kurt H. Johnsen

    2009-01-01

    Evidence is mixed on how well longleaf pine (Pinus palustris Mill.) responds to increased soil nitrogen via fertilization. We examined growth and physiological responses of volunteer longleaf pine trees within an intensive loblolly pine (Pinus taeda L.) fertilization experiment. Fertilizer was applied annually following thinning at age 8 years (late 1992) at rates...

  19. High diversity and suggested endemicity of culturable Actinobacteria in an extremely oligotrophic desert oasis

    Directory of Open Access Journals (Sweden)

    Hector Fernando Arocha-Garza

    2017-05-01

    Full Text Available The phylum Actinobacteria constitutes one of the largest and anciently divergent phyla within the Bacteria domain. Actinobacterial diversity has been thoroughly researched in various environments due to its unique biotechnological potential. Such studies have focused mostly on soil communities, but more recently marine and extreme environments have also been explored, finding rare taxa and demonstrating dispersal limitation and biogeographic patterns for Streptomyces. To test the distribution of Actinobacteria populations on a small scale, we chose the extremely oligotrophic and biodiverse Cuatro Cienegas Basin (CCB, an endangered oasis in the Chihuahuan desert to assess the diversity and uniqueness of Actinobacteria in the Churince System with a culture-dependent approach over a period of three years, using nine selective media. The 16S rDNA of putative Actinobacteria were sequenced using both bacteria universal and phylum-specific primer pairs. Phylogenetic reconstructions were performed to analyze OTUs clustering and taxonomic identification of the isolates in an evolutionary context, using validated type species of Streptomyces from previously phylogenies as a reference. Rarefaction analysis for total Actinobacteria and for Streptomyces isolates were performed to estimate species’ richness in the intermediate lagoon (IL in the oligotrophic Churince system. A total of 350 morphologically and nutritionally diverse isolates were successfully cultured and characterized as members of the Phylum Actinobacteria. A total of 105 from the total isolates were successfully subcultured, processed for DNA extraction and 16S-rDNA sequenced. All strains belong to the order Actinomycetales, encompassing 11 genera of Actinobacteria; the genus Streptomyces was found to be the most abundant taxa in all the media tested throughout the 3-year sampling period. Phylogenetic analysis of our isolates and another 667 reference strains of the family Streptomycetaceae

  20. High diversity and suggested endemicity of culturable Actinobacteria in an extremely oligotrophic desert oasis

    Science.gov (United States)

    Arocha-Garza, Hector Fernando; Canales-Del Castillo, Ricardo; Eguiarte, Luis E.; Souza, Valeria

    2017-01-01

    The phylum Actinobacteria constitutes one of the largest and anciently divergent phyla within the Bacteria domain. Actinobacterial diversity has been thoroughly researched in various environments due to its unique biotechnological potential. Such studies have focused mostly on soil communities, but more recently marine and extreme environments have also been explored, finding rare taxa and demonstrating dispersal limitation and biogeographic patterns for Streptomyces. To test the distribution of Actinobacteria populations on a small scale, we chose the extremely oligotrophic and biodiverse Cuatro Cienegas Basin (CCB), an endangered oasis in the Chihuahuan desert to assess the diversity and uniqueness of Actinobacteria in the Churince System with a culture-dependent approach over a period of three years, using nine selective media. The 16S rDNA of putative Actinobacteria were sequenced using both bacteria universal and phylum-specific primer pairs. Phylogenetic reconstructions were performed to analyze OTUs clustering and taxonomic identification of the isolates in an evolutionary context, using validated type species of Streptomyces from previously phylogenies as a reference. Rarefaction analysis for total Actinobacteria and for Streptomyces isolates were performed to estimate species’ richness in the intermediate lagoon (IL) in the oligotrophic Churince system. A total of 350 morphologically and nutritionally diverse isolates were successfully cultured and characterized as members of the Phylum Actinobacteria. A total of 105 from the total isolates were successfully subcultured, processed for DNA extraction and 16S-rDNA sequenced. All strains belong to the order Actinomycetales, encompassing 11 genera of Actinobacteria; the genus Streptomyces was found to be the most abundant taxa in all the media tested throughout the 3-year sampling period. Phylogenetic analysis of our isolates and another 667 reference strains of the family Streptomycetaceae shows that our

  1. Rate-determining Step of Flap Endonuclease 1 (FEN1) Reflects a Kinetic Bias against Long Flaps and Trinucleotide Repeat Sequences.

    Science.gov (United States)

    Tarantino, Mary E; Bilotti, Katharina; Huang, Ji; Delaney, Sarah

    2015-08-21

    Flap endonuclease 1 (FEN1) is a structure-specific nuclease responsible for removing 5'-flaps formed during Okazaki fragment maturation and long patch base excision repair. In this work, we use rapid quench flow techniques to examine the rates of 5'-flap removal on DNA substrates of varying length and sequence. Of particular interest are flaps containing trinucleotide repeats (TNR), which have been proposed to affect FEN1 activity and cause genetic instability. We report that FEN1 processes substrates containing flaps of 30 nucleotides or fewer at comparable single-turnover rates. However, for flaps longer than 30 nucleotides, FEN1 kinetically discriminates substrates based on flap length and flap sequence. In particular, FEN1 removes flaps containing TNR sequences at a rate slower than mixed sequence flaps of the same length. Furthermore, multiple-turnover kinetic analysis reveals that the rate-determining step of FEN1 switches as a function of flap length from product release to chemistry (or a step prior to chemistry). These results provide a kinetic perspective on the role of FEN1 in DNA replication and repair and contribute to our understanding of FEN1 in mediating genetic instability of TNR sequences. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  2. Damage by pathogens and insects to Scots pine and lodgepole pine 25 years after reciprocal plantings in Canada and Sweden

    OpenAIRE

    Fries, Anders

    2017-01-01

    A combined species - provenance - family experiment with Scots pine and lodgepole pine was planted in Canada and Sweden. One aim of the experiment was to evaluate the two species' sensitivities to pathogens and insects 25 years after establishment in their non-native continents. In Canada, Scots pine had better average survival than lodgepole pine, but survival rates among trees from the best seed-lots were equal. In Canada only western gall rust infected Scots pine to some extent, and mounta...

  3. 1H Nuclear Magnetic Resonance of Lodgepole Pine Wood Chips Affected by the Mountain Pine Beetle

    Directory of Open Access Journals (Sweden)

    Hartwig Peemoeller

    2010-12-01

    Full Text Available In this study, wood-water interactions of mountain pine beetle affected lodgepole pine were found to vary with time since death. Based on an analysis of magnetization components and spin-spin relaxation times from 1H NMR, it was determined that the mountain pine beetle attack does not affect the crystalline structure of the wood. Both the amorphous structure and the water components vary with time since death, which could be due to the fungi present after a mountain pine beetle attack, as well as the fact that wood from the grey-stage of attack cycles seasonally through adsorption and desorption in the stand.

  4. ¹H Nuclear Magnetic Resonance of Lodgepole Pine Wood Chips Affected by the Mountain Pine Beetle.

    Science.gov (United States)

    Todoruk, Tara M; Hartley, Ian D; Teymoori, Roshanak; Liang, Jianzhen; Peemoeller, Hartwig

    2010-12-31

    In this study, wood-water interactions of mountain pine beetle affected lodgepole pine were found to vary with time since death. Based on an analysis of magnetization components and spin-spin relaxation times from 1H NMR, it was determined that the mountain pine beetle attack does not affect the crystalline structure of the wood. Both the amorphous structure and the water components vary with time since death, which could be due to the fungi present after a mountain pine beetle attack, as well as the fact that wood from the grey-stage of attack cycles seasonally through adsorption and desorption in the stand.

  5. Hybridization in naturally regenerated shortleaf pine as affected by the distance to nearby artificially regenerated stands of loblolly pine

    Science.gov (United States)

    John F. Stewart; Charles G. Tauer; James M. Guldin; C. Dana Nelson

    2013-01-01

    The natural range of shortleaf pine encompasses 22 states from New York to Texas, second only to eastern white pine in the eastern United States. It is a species of minor and varying occurrence in most of these states usually found in association with other pines, but it is the only naturally occurring pine in the northwestern part of its range in Oklahoma, Arkansas,...

  6. Pine needle abortion biomarker detected in bovine fetal fluids

    Science.gov (United States)

    Pine needle abortion is a naturally occurring condition in free-range cattle caused by the consumption of pine needles from select species of cypress, juniper, pine, and spruce trees. Confirmatory diagnosis of pine needle abortion has previously relied on a combined case history of pine needle cons...

  7. Dose-dependent pheromone responses of mountain pine beetle in stands of lodgepole pine

    Science.gov (United States)

    Daniel R. Miller; B. Staffan Lindgren; John H. Borden

    2005-01-01

    We conducted seven behavioral choice tests with Lindgren multiple-funnel traps in stands of mature lodgepole pine in British Columbia, from 1988 to 1994, to determine the dosedependent responses of the mountain pine beetle, Dendroctonus ponderosae Hopkins, to its pheromones. Amultifunctional dose-dependent response was exhibited by D. ...

  8. Mountain pine beetle-killed lodgepole pine for the production of submicron lignocellulose fibrils

    Science.gov (United States)

    Ingrid Hoeger; Rolland Gleisner; Jose Negron; Orlando J. Rojas; J. Y. Zhu

    2014-01-01

    The elevated levels of tree mortality attributed to mountain pine beetle (MPB) (Dendroctonus ponderosae Hopkins) in western North American forests create forest management challenges. This investigation introduces the production of submicron or nanometer lignocellulose fibrils for value-added materials from the widely available resource represented by dead pines after...

  9. E-sports: um fenómeno da cultura digital contemporânea

    OpenAIRE

    Saraiva, Pedro André Cardoso

    2013-01-01

    Mestrado em Comunicação, Cultura e Tecnologias de Informação A competição entre dois jogadores está na génese dos jogos digitais e é esse o fator que está no centro deste trabalho, que explora o fenómeno do desporto eletrónico, os e-sports. Este conceito representa a prática competitiva e profissionalmente organizada nos videojogos. Situado conceptualmente entre o gaming e o desporto, os e-sports apresentam-se como um fenómeno da cultura digital contemporânea, partic...

  10. Primary marine aerosol emissions from the Mediterranean Sea during pre-bloom and oligotrophic conditions: correlations to seawater chlorophyll a from a mesocosm study

    Science.gov (United States)

    Schwier, A. N.; Rose, C.; Asmi, E.; Ebling, A. M.; Landing, W. M.; Marro, S.; Pedrotti, M.-L.; Sallon, A.; Iuculano, F.; Agusti, S.; Tsiola, A.; Pitta, P.; Louis, J.; Guieu, C.; Gazeau, F.; Sellegri, K.

    2015-07-01

    The effect of ocean acidification and changing water conditions on primary (and secondary) marine aerosol emissions is not well understood on a regional or a global scale. To investigate this effect as well as the indirect effect on aerosol that changing biogeochemical parameters can have, ~ 52 m3 pelagic mesocosms were deployed for several weeks in the Mediterranean Sea during both winter pre-bloom and summer oligotrophic conditions and were subjected to various levels of CO2 to simulate the conditions foreseen in this region for the coming decades. After seawater sampling, primary bubble-bursting aerosol experiments were performed using a plunging water jet system to test both chemical and physical aerosol parameters (10-400 nm). Comparing results obtained during pre-bloom and oligotrophic conditions, we find the same four log-normal modal diameters (18.5 ± 0.6, 37.5 ± 1.4, 91.5 ± 2.0, 260 ± 3.2 nm) describing the aerosol size distribution during both campaigns, yet pre-bloom conditions significantly increased the number fraction of the second (Aitken) mode, with an amplitude correlated to virus-like particles, heterotrophic prokaryotes, TEPs (transparent exopolymeric particles), chlorophyll a and other pigments. Organic fractions determined from kappa closure calculations for the diameter, Dp ~ 50 nm, were much larger during the pre-bloom period (64 %) than during the oligotrophic period (38 %), and the organic fraction decreased as the particle size increased. Combining data from both campaigns together, strong positive correlations were found between the organic fraction of the aerosol and chlorophyll a concentrations, heterotrophic and autotrophic bacteria abundance, and dissolved organic carbon (DOC) concentrations. As a consequence of the changes in the organic fraction and the size distributions between pre-bloom and oligotrophic periods, we find that the ratio of cloud condensation nuclei (CCN) to condensation nuclei (CN) slightly decreased during the

  11. Compostos fenólicos totais e antocianinas em suco de uva

    OpenAIRE

    Malacrida,Cassia R.; Motta,Silvana da

    2005-01-01

    As concentrações de compostos fenólicos totais e antocianinas em sucos de uva reconstituídos e simples, de diferentes marcas, disponíveis no comércio varejista da região metropolitana de Belo Horizonte (Minas Gerais) foram quantificadas. Também se determinou a contribuição das antocianinas poliméricas à cor e o índice de degradação das antocianinas. Os teores de compostos fenólicos totais variaram entre 0,27 e 2,41 g/L e as concentrações de antocianinas de 1,17 a 66,80 mg/L. Foram observadas ...

  12. Pine weevil feeding in Scots pine and Norway spruce regenerations

    OpenAIRE

    Wallertz, Kristina

    2009-01-01

    Damage caused by the pine weevil, Hylobius abietis (L) feeding on conifer seedlings is a major problem in reforested areas in many parts of Europe. The adult weevil feeds on the stem-bark of young seedlings, frequently killing a large proportion of newly planted seedlings. The aims of the studies underlying this thesis were to investigate whether additional food supplies could decrease the damage caused by pine weevil to seedlings, and to determine whether access to extra food might explain w...

  13. Fenómenos mixtos en la división neurosis y psicosis: un estudio de las elaboraciones freudianas

    OpenAIRE

    Aguirre, Javier

    2013-01-01

    El presente trabajo aborda algunos desarrollos freudianos referidos a la división neurosis y psicosis. El análisis se centra en la hipótesis referida a la existencia de fenómenos mixtos, neuróticos y psicóticos, o sea, fenómenos que se presentarían de una misma manera en su articulación en ambas categorías. Se concluye que la expresión “fenómenos mixtos” no es adecuada, en la medida que Freud aborda el fenómeno siempre de una manera articulada y no de una manera aislada, es decir, la caracter...

  14. Compostos fenólicos e capacidade antioxidante em frutos de tomateiros mutantes fotomorfogenéticos

    Directory of Open Access Journals (Sweden)

    Tiago Dias

    2015-05-01

    Full Text Available Compostos fenólicos e capacidade antioxidante são mecanismos de defesa das plantas aos danos do estresse oxidativo. Os compostos fenólicos são sintetizados pela via dos fenilpropanoides, cuja enzima chave, fenilalanina amônia liase, é influenciada pela luz e ação de fotorreceptores, como o fitocromo. O objetivo do presente trabalho é avaliar a concentração de compostos fenólicos e a capacidade antioxidante de frutos de microtomateiro selvagem, cultivar "Micro-Tom" (MT, e seus mutantes fotomorfogenéticos high pigment 1 (hp1, super-responsivo a eventos mediados por luz e aurea (au, deficiente quantitativo em fitocromos. Vinte frutos maduros de cada genótipo (MT, hp1 e au foram utilizados para as análises, realizadas em triplicata. Para quantificação dos compostos fenólicos totais, foi utilizado o método de Folin-Ciocalteu e a capacidade antioxidante foi realizada pelos métodos Ferric Reducing Antioxidant Power (FRAP e 2,2-diphenyl-1-picrylhydrazyl (DPPH. Os frutos do mutante hp1 apresentaram maiores conteúdos de compostos fenólicos totais e também maior capacidade antioxidante em relação à cultivar selvagem ("MT" e ao mutante au, o qual não diferiu significativamente da cultivar "MT".

  15. Regeneration of different plant functional types in a Masson pine forest following pine wilt disease.

    Science.gov (United States)

    Hu, Guang; Xu, Xuehong; Wang, Yuling; Lu, Gao; Feeley, Kenneth J; Yu, Mingjian

    2012-01-01

    Pine wilt disease is a severe threat to the native pine forests in East Asia. Understanding the natural regeneration of the forests disturbed by pine wilt disease is thus critical for the conservation of biodiversity in this realm. We studied the dynamics of composition and structure within different plant functional types (PFTs) in Masson pine forests affected by pine wilt disease (PWD). Based on plant traits, all species were assigned to four PFTs: evergreen woody species (PFT1), deciduous woody species (PFT2), herbs (PFT3), and ferns (PFT4). We analyzed the changes in these PFTs during the initial disturbance period and during post-disturbance regeneration. The species richness, abundance and basal area, as well as life-stage structure of the PFTs changed differently after pine wilt disease. The direction of plant community regeneration depended on the differential response of the PFTs. PFT1, which has a higher tolerance to disturbances, became dominant during the post-disturbance regeneration, and a young evergreen-broad-leaved forest developed quickly after PWD. Results also indicated that the impacts of PWD were dampened by the feedbacks between PFTs and the microclimate, in which PFT4 played an important ecological role. In conclusion, we propose management at the functional type level instead of at the population level as a promising approach in ecological restoration and biodiversity conservation.

  16. The push–pull tactic for mitigation of mountain pine beetle (Coleoptera: Curculionidae) damage in lodgepole and whitebark pines

    Science.gov (United States)

    Nancy E. Gillette; Constance J. Mehmel; Sylvia R. Mori; Jeffrey N. Webster; David L. Wood; Nadir Erbilgin; Donald R. Owen

    2012-01-01

    In an attempt to improve semiochemical-based treatments for protecting forest stands from bark beetle attack, we compared push-pull versus push-only tactics for protecting lodgepole pine (Pinus contorta Douglas ex Loudon) and whitebark pine (Pinus albicaulis Engelm.) stands from attack by mountain pine beetle (...

  17. Predictions of fire behavior and resistance to control: for use with photo series for the ponderosa pine type, ponderosa pine and associated species type, and lodgepole pine type.

    Science.gov (United States)

    Franklin R. Ward; David V. Sandberg

    1981-01-01

    This publication presents tables on the behavior of fire and the resistance of fuels to control. The information is to be used with the publication, "Photo Series for Quantifying Forest Residues in the Ponderosa Pine Type, Ponderosa Pine and Associated Species Type, Lodgepole Pine Type" (Maxwell, Wayne G.; Ward, Franklin R. 1976. Gen. Tech. Rep. PNW-GTR-052....

  18. Silvicultural treatments for converting loblolly pine to longleaf pine dominance: Effects on resource availability and their relationships with planted longleaf pine seedlings

    Science.gov (United States)

    Huifeng Hu; G.Geoff Wang; Joan L. Walker; Benjamin O. Knapp

    2012-01-01

    Throughout the southeastern United States, land managers are currently interested in converting loblolly pine (Pinus taeda L.) plantations to species rich longleaf pine (Pinus palustris Mill.) ecosystems. In a 3-year study on moderately well- to well-drained soils of the Lower Coastal Plain in North Carolina, we examined the...

  19. Una revisión del fenómeno de aislamiento magnético

    Directory of Open Access Journals (Sweden)

    Zósimo Arévalo Velosa

    2007-09-01

    Full Text Available Los dispositivos de alta energía son diseñados para que funcionen con campos eléctricos y magnéticos extrema-damente altos. Debido a esto, dichos dispositivos presentan fenómenos y comportamientos no lineales, como el aislamiento magnético que altera el transporte de los electrones. La no linealidad ha obligado a analizar y revisar desde el punto de vista matemático las condiciones de frontera y las soluciones del problema. El objetivo de este trabajo es exponer el tema a un nivel que facilite su difusión entre la comunidad académica no familiarizada con el mismo. Para ello, el trabajo presenta una descripción de los fenómenos que se generan cuando hay campos eléctricos y magnéticos muy altos, tomando el caso de un diodo plano al vacío, así como las ecuaciones que modelan el fenómeno de aislamiento magnético; también demuestra la existencia de las soluciones y encuentra las positivas en base a los métodos de solución superior e inferior para problemas de valor de frontera, y pro-porciona algunos ejemplos de aplicación del fenómeno de aislamiento magnético.

  20. The effect of water limitation on volatile emission, tree defense response, and brood success of Dendroctonus ponderosae in two pine hosts, lodgepole and jack pine

    Directory of Open Access Journals (Sweden)

    Inka eLusebrink

    2016-02-01

    Full Text Available The mountain pine beetle (MPB; Dendroctonus ponderosae has recently expanded its range from lodgepole pine forest into the lodgepole × jack pine hybrid zone in central Alberta, within which it has attacked pure jack pine. This study tested the effects of water limitation on tree defense response of mature lodgepole and jack pine (Pinus contorta and Pinus banksiana trees in the field. Tree defense response was initiated by inoculation of trees with the MPB-associated fungus Grosmannia clavigera and measured through monoterpene emission from tree boles and concentration of defensive compounds in phloem, needles, and necrotic tissues. Lodgepole pine generally emitted higher amounts of monoterpenes than jack pine; particularly from fungal-inoculated trees. Compared to non-inoculated trees, fungal inoculation increased monoterpene emission in both species, whereas water treatment had no effect on monoterpene emission. The phloem of both pine species contains (--α-pinene, the precursor of the beetle’s aggregation pheromone, however lodgepole pine contains two times as much as jack pine. The concentration of defensive compounds was 70-fold greater in the lesion tissue in jack pine, but only 10-fold in lodgepole pine compared to healthy phloem tissue in each species, respectively. Water-deficit treatment inhibited an increase of L-limonene as response to fungal inoculation in lodgepole pine phloem. The amount of myrcene in jack pine phloem was higher in water-deficit trees compared to ambient trees. Beetles reared in jack pine were not affected by either water or biological treatment, whereas beetles reared in lodgepole pine benefited from fungal inoculation by producing larger and heavier female offspring. Female beetles that emerged from jack pine bolts contained more fat than those that emerged from lodgepole pine, even though lodgepole pine phloem had a higher nitrogen content than jack pine phloem. These results suggest that jack pine chemistry

  1. Filtering fens: Mechanisms explaining phosphorus-limited hotspots of biodiversity in wetlands adjacent to heavily fertilized areas

    NARCIS (Netherlands)

    Cusell, C.; Kooijman, A.; Fernandez, F.; van Wirdum, G.; Geurts, J.J.M.; van Loon, E.E.; Kalbitz, K.; Lamers, L.P.M.

    2014-01-01

    The conservation of biodiverse wetland vegetation, including that of rich fens, has a high priority at a global scale. Although P-eutrophication may strongly decrease biodiversity in rich fens, some well-developed habitats do still survive in highly fertilized regions due to nutrient filtering

  2. Bio-composites made from pine straw

    Science.gov (United States)

    Cheng Piao; Todd F. Shupe; Chung Y. Hse; Jamie Tang

    2004-01-01

    Pine straw is renewable natural resource that is under-utilized. The objective of this study was to evaluate the physical and mechanical performances of pine straw composites. Three panel density levels (0.8, 0.9, 1.0 g/cm2) and two resin content levels (1% pMDI + 4% UF, 2% pMDI + 4% UF) were selected as treatments. For the pine-straw-bamboo-...

  3. Mountain pine beetle attack alters the chemistry and flammability of lodgepole pine foliage

    Science.gov (United States)

    Wesley G. Page; Michael J. Jenkins; Justin B. Runyon

    2012-01-01

    During periods with epidemic mountain pine beetle (Dendroctonus ponderosae Hopkins) populations in lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) forests, large amounts of tree foliage are thought to undergo changes in moisture content and chemistry brought about by tree decline and death. However, many of the presumed changes have yet to be...

  4. White pine blister rust resistance in limber pine: Evidence for a major gene

    Science.gov (United States)

    A. W. Schoettle; R. A. Sniezko; A. Kegley; K. S. Burns

    2014-01-01

    Limber pine (Pinus flexilis) is being threatened by the lethal disease white pine blister rust caused by the non-native pathogen Cronartium ribicola. The types and frequencies of genetic resistance to the rust will likely determine the potential success of restoration or proactive measures. These first extensive inoculation trials using individual tree seed collections...

  5. Development and assessment of 30-meter pine density maps for landscape-level modeling of mountain pine beetle dynamics

    Science.gov (United States)

    Benjamin A. Crabb; James A. Powell; Barbara J. Bentz

    2012-01-01

    Forecasting spatial patterns of mountain pine beetle (MPB) population success requires spatially explicit information on host pine distribution. We developed a means of producing spatially explicit datasets of pine density at 30-m resolution using existing geospatial datasets of vegetation composition and structure. Because our ultimate goal is to model MPB population...

  6. Seedling regeneration on decayed pine logs after the deforestation events caused by pine wilt disease

    Directory of Open Access Journals (Sweden)

    Y. Fukasawa

    2016-12-01

    Full Text Available Coarse woody debris (CWD forms an important habitat suitable for tree seedling establishment, and the CWD decay process influences tree seedling community. In Japan, a severe dieback of Pinus densiflora Sieb. & Zucc. caused by pine wilt disease (PWD damaged huge areas of pine stands but creates huge mass of pine CWD. It is important to know the factors influencing seedling colonization on pine CWD and their variations among geographical gradient in Japan to expect forest regeneration in post-PWD stands. I conducted field surveys on the effects of latitude, climates, light condition, decay type of pine logs, and log diameter on tree seedling colonization at ten geographically distinct sites in Japan. In total, 59 tree taxa were recorded as seedlings on pine logs. Among them, 13 species were recorded from more than five sites as adult trees or seedlings and were used for the analyses. A generalized linear model showed that seedling colonization of Pinus densiflora was negatively associated with brown rot in sapwood, while that of Rhus trichocarpa was positively associated with brown rot in heartwood. Regeneration of Ilex macropoda had no relationships with wood decay type but negatively associated with latitude and MAT, while positively with log diameter. These results suggested that wood decay type is a strong determinant of seedling establishment for certain tree species, even at a wide geographical scale; however, the effect is tree species specific.

  7. Preparation of Fe-cored carbon nanomaterials from mountain pine beetle-killed pine wood

    Science.gov (United States)

    Sung Phil Mun; Zhiyong Cai; Jilei Zhang

    2015-01-01

    The mountain pine beetle-killed lodgepole pine (Pinus contorta) wood treated with iron (III) nitrate solution was used for the preparation of Fe-cored carbon nanomaterials (Fe-CNs) under various carbonization temperatures. The carbonization yield of Fe-treated sample (5% as Fe) was always 1–3% higher (after ash compensation) than that of the non-...

  8. Threats, status & management options for bristlecone pines and limber pines in Southern Rockies

    Science.gov (United States)

    A. W. Schoettle; K. S. Burns; F. Freeman; R. A. Sniezko

    2006-01-01

    High-elevation white pines define the most remote alpine-forest ecotones in western North America yet they are not beyond the reach of a lethal non-native pathogen. The pathogen (Cronartium ribicola), a native to Asia, causes the disease white pine blister rust (WPBR) and was introduced into western Canada in 1910. Whitebark (Pinus albicaulis) and...

  9. Growth, aboveground biomass, and nutrient concentration of young Scots pine and lodgepole pine in oil shale post-mining landscapes in Estonia.

    Science.gov (United States)

    Kuznetsova, Tatjana; Tilk, Mari; Pärn, Henn; Lukjanova, Aljona; Mandre, Malle

    2011-12-01

    The investigation was carried out in 8-year-old Scots pine (Pinus sylvestris L.) and lodgepole pine (Pinus contorta var. latifolia Engelm.) plantations on post-mining area, Northeast Estonia. The aim of the study was to assess the suitability of lodgepole pine for restoration of degraded lands by comparing the growth, biomass, and nutrient concentration of studied species. The height growth of trees was greater in the Scots pine stand, but the tree aboveground biomass was slightly larger in the lodgepole pine stand. The aboveground biomass allocation to the compartments did not differ significantly between species. The vertical distribution of compartments showed that 43.2% of the Scots pine needles were located in the middle layer of the crown, while 58.5% of the lodgepole pine needles were in the lowest layer of the crown. The largest share of the shoots and stem of both species was allocated to the lowest layer of the crown. For both species, the highest NPK concentrations were found in the needles and the lowest in the stems. On the basis of the present study results, it can be concluded that the early growth of Scots pine and lodgepole pine on oil shale post-mining landscapes is similar.

  10. Impact of a Mountain Pine Beetle Outbreak on Young Lodgepole Pine Stands in Central British Columbia

    OpenAIRE

    Dhar, Amalesh; Balliet, Nicole; Runzer, Kyle; Hawkins, Christopher

    2015-01-01

    The current mountain pine beetle (MPB) (Dendroctonous ponderosae Hopkins) epidemic has severely affected pine forests of Western Canada and killed millions of hectares of lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) forest. Generally, MPB attack larger and older (diameter > 20 cm or >60 years of age) trees, but the current epidemic extends this limit with attacks on even younger and smaller trees. The study’s aim was to investigate the extent of MPB attack in y...

  11. A multiple antibiotic and serum resistant oligotrophic strain, Klebsiella pneumoniae MB45 having novel dfrA30, is sensitive to ZnO QDs

    Directory of Open Access Journals (Sweden)

    Chakrabarti Pinak

    2011-05-01

    Full Text Available Abstract Background The aim of this study was to describe a novel trimethoprim resistance gene cassette, designated dfrA30, within a class 1 integron in a facultatively oligotrophic, multiple antibiotic and human serum resistant test strain, MB45, in a population of oligotrophic bacteria isolated from the river Mahananda; and to test the efficiency of surface bound acetate on zinc oxide quantum dots (ZnO QDs as bactericidal agent on MB45. Methods Diluted Luria broth/Agar (10-3 media was used to cultivate the oligotrophic bacteria from water sample. Multiple antibiotic resistant bacteria were selected by employing replica plate method. A rapid assay was performed to determine the sensitivity/resistance of the test strain to human serum. Variable region of class 1 integron was cloned, sequenced and the expression of gene coding for antibiotic resistance was done in Escherichia coli JM 109. Identity of culture was determined by biochemical phenotyping and 16S rRNA gene sequence analyses. A phylogenetic tree was constructed based on representative trimethoprim resistance-mediating DfrA proteins retrieved from GenBank. Growth kinetic studies for the strain MB45 were performed in presence of varied concentrations of ZnO QDs. Results and conclusions The facultatively oligotrophic strain, MB45, resistant to human serum and ten antibiotics trimethoprim, cotrimoxazole, ampicillin, gentamycin, netilmicin, tobramycin, chloramphenicol, cefotaxime, kanamycin and streptomycin, has been identified as a new strain of Klebsiella pneumoniae. A novel dfr gene, designated as dfrA30, found integrated in class 1 integron was responsible for resistance to trimethoprim in Klebsiella pneumoniae strain MB45. The growth of wild strain MB45 was 100% arrested at 500 mg/L concentration of ZnO QDs. To our knowledge this is the first report on application of ZnO quantum dots to kill multiple antibiotics and serum resistant K. pneumoniae strain.

  12. Identification of human flap endonuclease 1 (FEN1) inhibitors using a machine learning based consensus virtual screening.

    Science.gov (United States)

    Deshmukh, Amit Laxmikant; Chandra, Sharat; Singh, Deependra Kumar; Siddiqi, Mohammad Imran; Banerjee, Dibyendu

    2017-07-25

    Human Flap endonuclease1 (FEN1) is an enzyme that is indispensable for DNA replication and repair processes and inhibition of its Flap cleavage activity results in increased cellular sensitivity to DNA damaging agents (cisplatin, temozolomide, MMS, etc.), with the potential to improve cancer prognosis. Reports of the high expression levels of FEN1 in several cancer cells support the idea that FEN1 inhibitors may target cancer cells with minimum side effects to normal cells. In this study, we used large publicly available, high-throughput screening data of small molecule compounds targeted against FEN1. Two machine learning algorithms, Support Vector Machine (SVM) and Random Forest (RF), were utilized to generate four classification models from huge PubChem bioassay data containing probable FEN1 inhibitors and non-inhibitors. We also investigated the influence of randomly selected Zinc-database compounds as negative data on the outcome of classification modelling. The results show that the SVM model with inactive compounds was superior to RF with Matthews's correlation coefficient (MCC) of 0.67 for the test set. A Maybridge database containing approximately 53 000 compounds was screened and top ranking 5 compounds were selected for enzyme and cell-based in vitro screening. The compound JFD00950 was identified as a novel FEN1 inhibitor with in vitro inhibition of flap cleavage activity as well as cytotoxic activity against a colon cancer cell line, DLD-1.

  13. Design, construction and performance of an experimental watershed to support a fen peatland for mine landscape reclamation

    Science.gov (United States)

    Price, J. S.; Petrone, R. M.; Strack, M.; Cooper, D. J.

    2017-12-01

    In the Alberta oil sands region, fen peatlands comprised 50% of the boreal landscape. Oil sands mining has stripped over 800 km2 of land surface to access bitumen, necessitating landscape reclamation to re-establish functional wetlands. Fens are peat-dominated wetlands that commonly rely on groundwater to supplement their water budget and deliver dissolved solutes that impart a distinct geochemistry, hence vegetation community. A numerical model was used to test the concept and guide selection of earth materials and system geometry. The goal was to maintain the placed peat in a sufficiently wet condition to support wetland plants and become a net carbon sink, in this sub-humid climate. The 32.1 ha Nikanotee Fen Watershed comprises a 7.7 ha upland, that was designed to recharge sufficient water, and deliver it to the 2.9 ha fen via groundwater flow. These features are surrounded by other reclaimed slopes designed to store water, rather than deliver it downslope. Four years of monitoring since construction show the fen maintains a high water table, and the peatland has become a strong carbon sink, even though the hydrological performance of construction materials varied substantially from what was anticipated (lower hydraulic conductivity). However, solutes associated with the tailings sand used in construction are moving towards the fen, and are expected to influence the future vegetation community and system biogeochemistry. One of the biggest uncertainties is the changing performance of soils and vegetation as they develop.

  14. Field effect of P fertilization on N$_{2}$ fixation rate of Ulex europaeus

    OpenAIRE

    Cavard , Xavier; Augusto , Laurent; Saur , Etienne; Trichet , Pierre

    2007-01-01

    European gorse (Ulex europaeus L.) N-2 fixation rate (% Ndfa) was studied in a maritime pine (Pinus pinaster Ait.) oligotrophic forest. Fertilization field trials were carried out on 5 sites with various inputs of phosphorus (0-240 kg P2O5. ha(-1)). Seven to ten years after pine planting, gorse were sampled to evaluate the effect of P fertilization on gorse % Ndfa, determined using the N-15 natural abundance method. One of the prerequisites of this method is the existence of a significant dif...

  15. Metódica: Articulación sistema teórico, fenómeno y procesos en el objeto de estudio. Una perspectiva desde el fenómeno pobreza

    OpenAIRE

    Yajaira Jiménez Zabala

    2011-01-01

    En este artículo discutimos la visión metódica que toma como apoyo el pivote entre lo cualitativo, lo cuantitativo y el orden de complejidad, en un enfoque plurimetódico, a través del cual se construyó la visión de la pobreza como objeto de estudio. Tal selección, está justificada en tanto se entiende la pobreza como un fenómeno social complejo, por las diversas aristas que le identifican. La combinación de los enfoques metodológicos permitió la aprehensión de los diferentes aspectos del fenó...

  16. Probability of infestation and extent of mortality models for mountain pine beetle in lodgepole pine forests in Colorado

    Science.gov (United States)

    Jose F. Negron; Jennifer G. Klutsch

    2017-01-01

    The mountain pine beetle, Dendroctonus ponderosae Hopkins, is a significant agent of tree mortality in lodgepole pine (Pinus contorta Dougl. ex Loud.) forests throughout western North America. A large outbreak of mountain pine beetle caused extensive tree mortality in north-central Colorado beginning in the late 1990s. We use data from a network of plots established in...

  17. Characterizing the physical and genetic structure of the lodgepole pine × jack pine hybrid zone: mosaic structure and differential introgression.

    Science.gov (United States)

    Cullingham, Catherine I; James, Patrick M A; Cooke, Janice E K; Coltman, David W

    2012-12-01

    Understanding the physical and genetic structure of hybrid zones can illuminate factors affecting their formation and stability. In north-central Alberta, lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia) and jack pine (Pinus banksiana Lamb) form a complex and poorly defined hybrid zone. Better knowledge of this zone is relevant, given the recent host expansion of mountain pine beetle into jack pine. We characterized the zone by genotyping 1998 lodgepole, jack pine, and hybrids from British Columbia, Alberta, Saskatchewan, Ontario, and Minnesota at 11 microsatellites. Using Bayesian algorithms, we calculated genetic ancestry and used this to model the relationship between species occurrence and environment. In addition, we analyzed the ancestry of hybrids to calculate the genetic contribution of lodgepole and jack pine. Finally, we measured the amount of gene flow between the pure species. We found the distribution of the pine classes is explained by environmental variables, and these distributions differ from classic distribution maps. Hybrid ancestry was biased toward lodgepole pine; however, gene flow between the two species was equal. The results of this study suggest that the hybrid zone is complex and influenced by environmental constraints. As a result of this analysis, range limits should be redefined.

  18. Experimental acidification of a poor fen in northwestern Ontario: Effects on emergence of Chironomidae (Diptera)

    Energy Technology Data Exchange (ETDEWEB)

    Rosenberg, D.M.; Wiens, A.P.; Bilyj, B. [Department of Fisheries and Oceans, Winnipeg, MB (Canada). Central and Arctic Region; Armstrong, L. [Department of Fisheries and Oceans, Winnipeg, MB (Canada). Central and Arctic Region

    1995-10-01

    The effects of experimental acidification and N fertilization on chironomid emergence from a poor fen in northwestern Ontario were studied from 1984 to 1989. Experimental treatments did not affect the numbers of chironomids emerging weekly, the timing of emergence, or the species composition of emergence during the study period. Weekly emergence counts were higher (P<0.05) from the periphery of the fen than the central part. Total seasonal emergence was higher from an area that was previously burned than from the rest of that swamp, though the difference was not statistically significant. Stability of species composition, despite experimental treatments and physiographic differences in the fen, may be a widespread characteristic of Canadian acidic peatlands. 7 tabs., 4 figs., 23 refs.

  19. Mountain pine beetle-killed trees as snags in Black Hills ponderosa pine stands

    Science.gov (United States)

    J. M. Schmid; S. A. Mata; W. C. Schaupp

    2009-01-01

    Mountain pine beetle-killed ponderosa pine trees in three stands of different stocking levels near Bear Mountain in the Black Hills National Forest were surveyed over a 5-year period to determine how long they persisted as unbroken snags. Rate of breakage varied during the first 5 years after MPB infestation: only one tree broke during the first 2 years in the three...

  20. Didymosphenia geminata: Algal blooms in oligotrophic streams and rivers

    Science.gov (United States)

    Sundareshwar, P. V.; Upadhayay, S.; Abessa, M.; Honomichl, S.; Berdanier, B.; Spaulding, S. A.; Sandvik, C.; Trennepohl, A.

    2011-05-01

    In recent decades, the diatom Didymosphenia geminata has emerged as nuisance species in river systems around the world. This periphytic alga forms large “blooms” in temperate streams, presenting a counterintuitive result: the blooms occur primarily in oligotrophic streams and rivers, where phosphorus (P) availability typically limits primary production. The goal of this study is to examine how high algal biomass is formed under low P conditions. We reveal a biogeochemical process by which D. geminata mats concentrate P from flowing waters. First, the mucopolysaccaride stalks of D. geminata adsorb both iron (Fe) and P. Second, enzymatic and bacterial processes interact with Fe to increase the biological availability of P. We propose that a positive feedback between total stalk biomass and high growth rate is created, which results in abundant P for cell division. The affinity of stalks for Fe in association with iron-phosphorus biogeochemistry suggest a resolution to the paradox of algal blooms in oliogotrophic streams and rivers.

  1. White pine blister rust resistance of 12 western white pine families at three field sites in the Pacific Northwest

    Science.gov (United States)

    Richard A. Sniezko; Robert Danchok; Jim Hamlin; Angelia Kegley; Sally Long; James Mayo

    2012-01-01

    Western white pine (Pinus monticola Douglas ex D. Don) is highly susceptible to the non-native, invasive pathogen Cronartium ribicola, the causative agent of white pine blister rust. The susceptibility of western white pine to blister rust has limited its use in restoration and reforestation throughout much of western North...

  2. Determination of natural organic matter and iron binding capacity in fen samples

    Science.gov (United States)

    Kügler, Stefan; Cooper, Rebecca E.; Frieder Mohr, Jan; Wichard, Thomas; Küsel, Kirsten

    2017-04-01

    Natural organic matter (NOM) plays an important role in ecosystem processes such as soil carbon stabilization, nutrient availability and metal complexation. Iron-NOM-complexes, for example, are known to increase the solubility and, as a result, the bioavailability of iron in natural environments leading to several effects on the microbial community. Due to the various functions of NOM in natural environments, there is a high level of interest in the characterization of the molecular composition. The complexity of NOM presents a significant challenge in the elucidation of its composition. However, the development and utilization of high resolution mass spectrometry (HR-MS) as a tool to detect single compounds in complex samples has spearheaded the effort to elucidate the composition of NOM. Over the past years, the accuracy of ion cyclotron- or Orbitrap mass spectrometers has increased dramatically resulting in the possibility to obtain a mass differentiation of the large number of compounds in NOM. Together these tools provide significant and powerful insight into the molecular composition of NOM. In the current study, we aim to understand abiotic and biotic interactions between NOM and metals, such as iron, found in the Schlöppnerbrunnen fen (Fichtelgebirge, Germany) and how these interactions impact the microbial consortia. We characterized the dissolved organic matter (DOM) as well as basic chemical parameters in the iron-rich (up to 20 mg (g wt peat)-1), slightly acidic (pH 4.8) fen to gain more information about DOM-metal interactions. This minerotrophic peatland connected to the groundwater has received Fe(II) released from the surrounding soils in the Lehstenbach catchment. Absorption spectroscopy (AAS), differential pulse polarography (DPP) and high resolution electrospray ionization mass spectrometry (HR-ESI-Orbitrap-MS) was applied to characterize the molecular composition of DOM in the peat water extract (PWE). We identified typical patterns for DOM

  3. Impact of pine needle leachates from a mountain pine beetle infested watershed on groundwater geochemistry

    Science.gov (United States)

    Pryhoda, M.; Sitchler, A.; Dickenson, E.

    2013-12-01

    The mountain pine beetle (MPB) epidemic in the northwestern United States is a recent indicator of climate change; having an impact on the lodgepole pine forest ecosystem productivity. Pine needle color can be used to predict the stage of a MPB infestation, as they change color from a healthy green, to red, to gray as the tree dies. Physical processes including precipitation and snowfall can cause leaching of pine needles in all infestation stages. Understanding the evolution of leachate chemistry through the stages of MPB infestation will allow for better prediction of the impact of MPBs on groundwater geochemistry, including a potential increase in soil metal mobilization and potential increases in disinfection byproduct precursor compounds. This study uses batch experiments to determine the leachate chemistry of pine needles from trees in four stages of MPB infestation from Summit County, CO, a watershed currently experiencing the MPB epidemic. Each stage of pine needles undergoes four subsequent leach periods in temperature-controlled DI water. The subsequent leaching method adds to the experiment by determining how leachate chemistry of each stage changes in relation to contact time with water. The leachate is analyzed for total organic carbon. Individual organic compounds present in the leachate are analyzed by UV absorption spectra, fluorescence spectrometry, high-pressure liquid chromatography for organic acid analysis, and size exclusion chromatography. Leachate chemistry results will be used to create a numerical model simulating reactions of the leachate with soil as it flows through to groundwater during precipitation and snowfall events.

  4. Diversity of picoeukaryotes at an oligotrophic site off the Northeastern Red Sea Coast.

    KAUST Repository

    Acosta, Francisco

    2013-08-20

    Picoeukaryotes are protists ≤ 3 μm composed of a wide diversity of taxonomic groups. They are an important constituent of the ocean\\'s microbiota and perform essential ecological roles in marine nutrient and carbon cycles. Despite their importance, the true extent of their diversity has only recently been uncovered by molecular surveys that resulted in the discovery of a substantial number of previously unknown groups. No study on picoeukaryote diversity has been conducted so far in the main Red Sea basin-a unique marine environment characterized by oligotrophic conditions, high levels of irradiance, high salinity and increased water temperature.

  5. Whitebark pine vulnerability to climate-driven mountain pine beetle disturbance in the Greater Yellowstone Ecosystem.

    Science.gov (United States)

    Logan, Jesse A; MacFarlane, William W; Willcox, Louisa

    2010-06-01

    Widespread outbreaks of mountain pine beetles (MPB) are occurring throughout the range of this native insect. Episodic outbreaks are a common occurrence in the beetles' primary host, lodgepole pine. Current outbreaks, however, are occurring in habitats where outbreaks either did not previously occur or were limited in scale. Herein, we address widespread, ongoing outbreaks in high-elevation, whitebark pine forests of the Greater Yellowstone Ecosystem, where, due to an inhospitable climate, past outbreaks were infrequent and short lived. We address the basic question: are these outbreaks truly unprecedented and a threat to ecosystem continuity? In order to evaluate this question we (1) present evidence that the current outbreak is outside the historic range of variability; (2) examine system resiliency to MPB disturbance based on adaptation to disturbance and host defenses to MPB attack; and (3) investigate the potential domain of attraction to large-scale MPB disturbance based on thermal developmental thresholds, spatial structure of forest types, and the confounding influence of an introduced pathogen. We conclude that the loss of dominant whitebark pine forests, and the ecological services they provide, is likely under continuing climate warming and that new research and strategies are needed to respond to the crisis facing whitebark pine.

  6. Evolutionary relationships of Slash Pine ( Pinus elliottii ) with its ...

    African Journals Online (AJOL)

    llozymes in bud tissue and monoterpene contents in xylem oleoresin of slash pine (Pinus elliottii) were analyzed from populations across the natural distribution, as well as those from other species in the AUSTRALES pines. Allozyme diversity measures of slash pine were similar to those found in other southern pines.

  7. Impacts of oil sands process water on fen plants: Implications for plant selection in required reclamation projects

    International Nuclear Information System (INIS)

    Pouliot, Rémy; Rochefort, Line; Graf, Martha D.

    2012-01-01

    Fen plant growth in peat contaminated with groundwater discharges of oil sands process water (OSPW) was assessed in a greenhouse over two growing seasons. Three treatments (non-diluted OSPW, diluted OSPW and rainwater) were tested on five vascular plants and four mosses. All vascular plants tested can grow in salinity and naphthenic acids levels currently produced by oil sands activity in northwestern Canada. No stress sign was observed after both seasons. Because of plant characteristics, Carex species (C. atherodes and C. utriculata) and Triglochin maritima would be more useful for rapidly restoring vegetation and creating a new peat-accumulating system. Groundwater discharge of OSPW proved detrimental to mosses under dry conditions and ensuring adequate water levels would be crucial in fen creation following oil sands exploitation. Campylium stellatum would be the best choice to grow in contaminated areas and Bryum pseudotriquetrum might be interesting as it has spontaneously regenerated in all treatments. - Highlights: ► Fen plant growth was assessed under groundwater discharges of oil sands process water. ► Sedge and grass species were not stressed after two growing seasons in greenhouse. ► Carex species and Triglochin maritima would be helpful in created contaminated fens. ► In dry conditions, contaminated groundwater discharge was detrimental for mosses. ► Campylium stellatum would be the best choice in created fens with contaminated water. - Sedges and grasses tolerated the contact with oil sands process water and could probably grow well in contaminated created fens, but mosses were particularly affected under dry conditions.

  8. High abundances of potentially active ammonia-oxidizing bacteria and archaea in oligotrophic, high-altitude lakes of the Sierra Nevada, California, USA.

    Directory of Open Access Journals (Sweden)

    Curtis J Hayden

    Full Text Available Nitrification plays a central role in the nitrogen cycle by determining the oxidation state of nitrogen and its subsequent bioavailability and cycling. However, relatively little is known about the underlying ecology of the microbial communities that carry out nitrification in freshwater ecosystems--and particularly within high-altitude oligotrophic lakes, where nitrogen is frequently a limiting nutrient. We quantified ammonia-oxidizing archaea (AOA and bacteria (AOB in 9 high-altitude lakes (2289-3160 m in the Sierra Nevada, California, USA, in relation to spatial and biogeochemical data. Based on their ammonia monooxygenase (amoA genes, AOB and AOA were frequently detected. AOB were present in 88% of samples and were more abundant than AOA in all samples. Both groups showed >100 fold variation in abundance between different lakes, and were also variable through time within individual lakes. Nutrient concentrations (ammonium, nitrite, nitrate, and phosphate were generally low but also varied across and within lakes, suggestive of active internal nutrient cycling; AOB abundance was significantly correlated with phosphate (r(2 = 0.32, p<0.1, whereas AOA abundance was inversely correlated with lake elevation (r(2 = 0.43, p<0.05. We also measured low rates of ammonia oxidation--indicating that AOB, AOA, or both, may be biogeochemically active in these oligotrophic ecosystems. Our data indicate that dynamic populations of AOB and AOA are found in oligotrophic, high-altitude, freshwater lakes.

  9. Evaluating potential fire behavior in lodgepole pine-dominated forests after a mountain pine beetle epidemic in north-central Colorado

    Science.gov (United States)

    Jennifer G. Klutsch; Mike A. Battaglia; Daniel R. West; Sheryl L. Costello; Jose F. Negron

    2011-01-01

    A mountain pine beetle outbreak in Colorado lodgepole pine forests has altered stand and fuel characteristics that affect potential fire behavior. Using the Fire and Fuels Extension to the Forest Vegetation Simulator, potential fire behavior was modeled for uninfested and mountain pine beetle-affected plots 7 years after outbreak initiation and 10 and 80% projected...

  10. Sapwood Stored Resources Decline in Whitebark and Lodgepole Pines Attacked by Mountain Pine Beetles (Coleoptera: Curculionidae).

    Science.gov (United States)

    Lahr, Eleanor C; Sala, Anna

    2016-12-01

    Recent outbreaks of forest insects have been directly linked to climate change-induced warming and drought, but effects of tree stored resources on insects have received less attention. We asked whether tree stored resources changed following mountain pine beetle (Dendroctonus ponderosae Hopkins) attack and whether they affected beetle development. We compared initial concentrations of stored resources in the sapwood of whitebark pine (Pinus albicaulis Engelmann) and lodgepole pine (Pinus contorta Douglas ex. Louden) with resource concentrations one year later, in trees that were naturally attacked by beetles and trees that remained unattacked. Beetles did not select host trees based on sapwood resources-there were no consistent a priori differences between attacked versus unattacked trees-but concentrations of nonstructural carbohydrate (NSC), lipids, and phosphorus declined in attacked trees, relative to initial concentrations and unattacked trees. Whitebark pine experienced greater resource declines than lodgepole pine; however, sapwood resources were not correlated with beetle success in either species. Experimental manipulation confirmed that the negative effect of beetles on sapwood and phloem NSC was not due to girdling. Instead, changes in sapwood resources were related to the percentage of sapwood with fungal blue-stain. Overall, mountain pine beetle attack affected sapwood resources, but sapwood resources did not contribute directly to beetle success; instead, sapwood resources may support colonization by beetle-vectored fungi that potentially accelerate tree mortality. Closer attention to stored resource dynamics will improve our understanding of the interaction between mountain pine beetles, fungi, and host trees, an issue that is relevant to our understanding of insect range expansion under climate change. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions

  11. Histology of white pine blister rust in needles of resistant and susceptible eastern white pine

    Science.gov (United States)

    Joel A. Jurgens; Robert A. Blanchette; Paul J. Zambino; Andrew David

    2003-01-01

    White pine blister rust, Cronartium ribicola, has plagued the forests of North America for almost a century. Over past decades, eastern white pine (Pinus strobus) that appear to tolerate the disease have been selected and incorporated into breeding programs. Seeds from P. strobus with putative resistance were...

  12. State of pine decline in the southeastern United States

    Science.gov (United States)

    Lori Eckhardt; Mary Anne Sword Sayer; Don Imm

    2010-01-01

    Pine decline is an emerging forest health issue in the southeastern United States. Observations suggest pine decline is caused by environmental stress arising from competition, weather, insects and fungi, anthropogenic disturbances, and previous management. The problem is most severe for loblolly pine on sites that historically supported longleaf pine, are highly...

  13. NO3 uptake in shallow, oligotrophic, mountain lakes: The influence of elevated NO3 concentrations

    Science.gov (United States)

    Nydick, K.R.; LaFrancois, B.M.; Baron, Jill S.

    2004-01-01

    Nutrient enrichment experiments were conducted in 1.2-m deep enclosures in 2 shallow, oligotrophic, mountain lakes. 15N-NO3 isotope tracer was used to compare the importance of phytoplankton and benthic compartments (epilithon, surface sediment [epipelon], and subsurface sediment) for NO3 uptake under high and low NO3 conditions. NO3 uptake approached saturation in the high-N lake, but not in the low-N lake. The capacity of phytoplankton and benthic compartments to take up NO3 differed among treatments and between lakes, and depended on water-column nutrient conditions and the history of NO3 availability. Phytoplankton productivity responded strongly to addition of limiting nutrients, and NO3 uptake was related to phytoplankton biomass and photosynthesis. However, more NO3 usually was taken up by benthic compartments (57–92% combined) than by phytoplankton, even though the response of benthic algal biomass to nutrient additions was less pronounced than that of phytoplankton and benthic NO3 uptake was unrelated to benthic algal biomass. In the low-N lake where NO3 uptake was unsaturated, C content or % was related to NO3 uptake in benthic substrates, suggesting that heterotrophic bacterial processes could be important in benthic NO3 uptake. These results suggest that phytoplankton are most sensitive to nutrient additions, but benthic processes are important for NO3 uptake in shallow, oligotrophic lakes.

  14. Revivification of a method for identifying longleaf pine timber and its application to southern pine relicts in southeastern Virginia

    Science.gov (United States)

    Thomas L. Eberhardt; Philip M. Sheridan; Arvind A.R. Bhuta

    2011-01-01

    Abstract: Longleaf pine (Pinus palustris Mill.) cannot be distinguished from the other southern pines based on wood anatomy alone. A method that involves measuring pith and second annual ring diameters, reported by Arthur Koehler in 1932 (The Southern Lumberman, 145: 36–37), was revisited as an option for identifying longleaf pine timbers and stumps. Cross-section...

  15. Large-scale thinning, ponderosa pine, and mountain pine beetle in the Black Hills, USA

    Science.gov (United States)

    Jose F. Negron; Kurt K. Allen; Angie Ambourn; Blaine Cook; Kenneth Marchand

    2017-01-01

    Mountain pine beetle (Dendroctonus ponderosae Hopkins) (MPB), can cause extensive ponderosa pine (Pinus ponderosa Dougl. ex Laws.) mortality in the Black Hills of South Dakota and Wyoming, USA. Lower tree densities have been associated with reduced MPB-caused tree mortality, but few studies have reported on large-scale thinning and most data come from small plots that...

  16. Silvicultural Considerations in Managing Southern Pine Stands in the Context of Southern Pine Beetle

    Science.gov (United States)

    James M. Guldin

    2011-01-01

    Roughly 30 percent of the 200 million acres of forest land in the South supports stands dominated by southern pines. These are among the most productive forests in the nation. Adapted to disturbance, southern pines are relatively easy to manage with even-aged methods such as clearcutting and planting, or the seed tree and shelterwood methods with natural regeneration....

  17. Phosphorus flux due to Atlantic salmon (Salmo salar) in an oligotrophic upland stream: effects of management and demography

    Science.gov (United States)

    Keith H. Nislow; John D. Armstrong; Simon. McKelvey

    2004-01-01

    Little is known concerning the role of Atlantic salmon (Salmo salar) in the transport of nutrients to and from river systems. We used demographic data from the River Bran, an oligotrophic river in Scotland, UK, to construct a budget for the transport of phosphorus (P) and applied it to investigate the effects of management strategies and demographic...

  18. The GAN Exonuclease or the Flap Endonuclease Fen1 and RNase HII Are Necessary for Viability of Thermococcus kodakarensis.

    Science.gov (United States)

    Burkhart, Brett W; Cubonova, Lubomira; Heider, Margaret R; Kelman, Zvi; Reeve, John N; Santangelo, Thomas J

    2017-07-01

    Many aspects of and factors required for DNA replication are conserved across all three domains of life, but there are some significant differences surrounding lagging-strand synthesis. In Archaea , a 5'-to-3' exonuclease, related to both bacterial RecJ and eukaryotic Cdc45, that associates with the replisome specifically through interactions with GINS was identified and designated GAN (for G INS- a ssociated n uclease). Despite the presence of a well-characterized flap endonuclease (Fen1), it was hypothesized that GAN might participate in primer removal during Okazaki fragment maturation, and as a Cdc45 homologue, GAN might also be a structural component of an archaeal CMG (Cdc45, MCM, and GINS) replication complex. We demonstrate here that, individually, either Fen1 or GAN can be deleted, with no discernible effects on viability and growth. However, deletion of both Fen1 and GAN was not possible, consistent with both enzymes catalyzing the same step in primer removal from Okazaki fragments in vivo RNase HII has also been proposed to participate in primer processing during Okazaki fragment maturation. Strains with both Fen1 and RNase HII deleted grew well. GAN activity is therefore sufficient for viability in the absence of both RNase HII and Fen1, but it was not possible to construct a strain with both RNase HII and GAN deleted. Fen1 alone is therefore insufficient for viability in the absence of both RNase HII and GAN. The ability to delete GAN demonstrates that GAN is not required for the activation or stability of the archaeal MCM replicative helicase. IMPORTANCE The mechanisms used to remove primer sequences from Okazaki fragments during lagging-strand DNA replication differ in the biological domains. Bacteria use the exonuclease activity of DNA polymerase I, whereas eukaryotes and archaea encode a flap endonuclease (Fen1) that cleaves displaced primer sequences. RNase HII and the GINS-associated exonuclease GAN have also been hypothesized to assist in primer

  19. Formation dynamics of FeN thin films on Cu(100)

    KAUST Repository

    Heryadi, Dodi; Schwingenschlö gl, Udo

    2012-01-01

    To investigate the structural and magnetic properties of thin films of FeN we have performed ab initio molecular dynamics simulations of their formation on Cu(100) substrates. The iron nitride layers exhibit a p4gm(2 × 2) reconstruction and order

  20. Impact of water-level changes to aquatic vegetation in small oligotrophic lakes

    Directory of Open Access Journals (Sweden)

    Egert VANDEL

    2016-06-01

    Full Text Available This study demonstrates the effect of drastic water-level changes to the aquatic vegetation in three small oligotrophic lakes situated in Kurtna Kame Field in north-eastern Estonia. The area holds around 40 lakes in 30 km2 of which 18 lakes are under protection as Natura Habitat lakes (Natura 2000 network. The area is under a strong human impact as it is surrounded by oil shale mines, sand quarry, peat harvesting field etc. The most severe impact comes from the groundwater intake established in 1972 in the vicinity of three studied lakes. The exploitation of groundwater led to drastic water-level drops. In 1980s the water-level drops were measured to be up to 3 to 4 meters compared to the levels of 1946. Lake Martiska and Lake Kuradijärv were severely affected and only 29% and 45% of lake area respectively and 21% of initial volume remained. Both lakes were described as oligotrophic lakes before severe human impact and held characteristic macrophytes such as Isoëtes lacustris L., Sparganium angustifolium Michx and Lobelia dortmanna L. As the water level declined the lakes lost their rare characteristic species and can now be described more as a meso- or even eutrophic lakes. When the volume of groundwater abstraction decreased in the 1990s the water levels started to recover but did not reach the natural levels of pre-industrialized era. Also the vegetation did not show any signs of recovery. In 2012 the pumping rates increased again causing a new rapid decline in water levels which almost exceed the previous minimum levels. The water-level monitoring alongside with the macrophyte monitoring data gives us a good case study on how the long term abrupt water-level changes can affect the aquatic vegetation

  1. Restoring sedges and mosses into frost heaving iron fens, San Juan Mountains, Colorado

    Directory of Open Access Journals (Sweden)

    R.A. Chimner

    2011-08-01

    Full Text Available Rare iron fens in the San Juan Mountains of Colorado are frequently in poor condition due to mining, roads and ditches, which have left much of the fen completely bare of vegetation. Natural revegetation is slow to occur in the bare areas because of severe frost heave in the cold mountain climate. Therefore, experimental revegetation plots were conducted in a factorial design with mulching and no mulching, crossed with moss diaspores, sedge transplants, and moss and sedge combined. Mulching influenced surface soil temperatures by reducing the midday highs and increasing the night-time lows, which decreased the frequency and amount of frost heave. Peat moisture also modified frost heave, with the greatest frost heaving occurring near 75 % peat moisture content (water table 10–20 cm below the surface and the least when soils were either wetter or drier. Moss survival was dependent on mulch, with no moss surviving in plots without mulch. Mulching also increased sedge transplant survival. In summary, mulching significantly increased the success of vegetation restoration efforts for frost heave areas in mountain fens.

  2. Prescribed Burn at Pine Bluff Arsenal

    National Research Council Canada - National Science Library

    Peacock, Lance

    2000-01-01

    .... Abandoned fields grew up in pine or in some cases were planted in pine during the 1930's. The burning of farm stubble and woodlands was a common practice in Arkansas throughout this time period...

  3. Identifying ponderosa pines infested with mountain pine beetles

    Science.gov (United States)

    William F. McCambridge

    1974-01-01

    Trees successfully and unsuccessfully attacked by mountain pine beetles have several symptoms in common, so that proper diagnosis is not always easy. Guidelines presented here enable the observer to correctly distinguish nearly all attacked trees.

  4. Violencia en la pareja, las caras del fenómeno

    Directory of Open Access Journals (Sweden)

    Luz Elena Ocampo Otálvaro

    2011-01-01

    Full Text Available Este trabajo pretende mostrar las diversas caras o facetas del fenómeno de la violencia en la pareja, el mismo que en la literatura es conocido como violencia conyugal, violencia doméstica, violencia por parte del compañero íntimo, etc. Se identifica como un problema de salud pública, debido a los altos costos que genera y la manera como lesiona la vida cotidiana de quienes lo padecen. Se manifiesta en el seno de las relaciones de pareja, e irradia hacia los diversos ámbitos de interacción de los actores: mujer, varón, niño, niña. Involucra a todo el grupo o los grupos familiares de quienes lo viven, y puede lesionar de forma severa a los mismos. Se revisan aspectos del fenómeno, como el hecho que no sólo se presenta en las relaciones en las que la pareja tenga una unión de hecho, sino también en parejas de novios. No solo afecta a las mujeres o a las niñas; también afecta a los hombres. Tampoco es exclusivo de las parejas heterosexuales; los estudios muestran que entre parejas del mismo sexo también está presente. Se trata entonces de un fenómeno universal, multicausal, multidimensional, de salud y de tipo legal, que genera consecuencias que incluyen desde un problema de autoestima, de ansiedad, de depresión, de estrés hasta la muerte misma.

  5. Biogeography and diversity of pines in the Madrean Archipelago

    Science.gov (United States)

    George M. Ferguson; Aaron D. Flesch; Thomas R. Van Devender

    2013-01-01

    Pines are important dominants in pine-oak, pine and mixed-conifer forests across the Colorado Plateau, southern Rocky Mountains, Sierra Madre Occidental, and in the intervening Sky Islands of the United States-Mexico borderlands. All 17 native species of pines in the Sky Islands region or their adjacent mountain mainlands reach the northern or southern margins of their...

  6. White pine blister rust in the interior Mountain West

    Science.gov (United States)

    Kelly Burns; Jim Blodgett; Dave Conklin; Brian Geils; Jim Hoffman; Marcus Jackson; William Jacobi; Holly Kearns; Anna Schoettle

    2010-01-01

    White pine blister rust is an exotic, invasive disease of white, stone, and foxtail pines (also referred to as white pines or five-needle pines) in the genus Pinus and subgenus Strobus (Price and others 1998). Cronartium ribicola, the fungus that causes WPBR, requires an alternate host - currants and gooseberries in the genus Ribes and species of Pedicularis...

  7. The lodgepole × jack pine hybrid zone in Alberta, Canada: a stepping stone for the mountain pine beetle on its journey East across the boreal forest?

    Science.gov (United States)

    Lusebrink, Inka; Erbilgin, Nadir; Evenden, Maya L

    2013-09-01

    Historical data show that outbreaks of the tree killing mountain pine beetle are often preceded by periods of drought. Global climate change impacts drought frequency and severity and is implicated in the range expansion of the mountain pine beetle into formerly unsuitable habitats. Its expanded range has recently reached the lodgepole × jack pine hybrid zone in central Alberta, Canada, which could act as a transition from its historical lodgepole pine host to a jack pine host present in the boreal forest. This field study tested the effects of water limitation on chemical defenses of mature trees against mountain pine beetle-associated microorganisms and on beetle brood success in lodgepole × jack pine hybrid trees. Tree chemical defenses as measured by monoterpene emission from tree boles and monoterpene concentration in needles were greater in trees that experienced water deficit compared to well-watered trees. Myrcene was identified as specific defensive compound, since it significantly increased upon inoculation with dead mountain pine beetles. Beetles reared in bolts from trees that experienced water deficit emerged with a higher fat content, demonstrating for the first time experimentally that drought conditions benefit mountain pine beetles. Further, our study demonstrated that volatile chemical emission from tree boles and phloem chemistry place the hybrid tree chemotype in-between lodgepole pine and jack pine, which might facilitate the host shift from lodgepole pine to jack pine.

  8. Perry Pinyon Pines Protection Project

    Science.gov (United States)

    Daniel McCarthy

    2012-01-01

    Fuel reduction treatments around pinyon pine trees began as a simple project but ended in something more complex, enjoyable, and rewarding. The project eventually led to pinyon species (Pinus monophylla and P. quadrifolia) reforestation efforts, something that has been tried in the past with disappointing results. The Perry Pinyon Pines Protection Project and current...

  9. Prescribed burning and mastication effects on surface fuels in southern pine beetle-killed loblolly pine plantations

    Science.gov (United States)

    Aaron D. Stottlemyer; Thomas A. Waldrop; G. Geoff Wang

    2015-01-01

    Surface fuels were characterized in loblolly pine (Pinus taeda L.) plantations severely impacted by southern pine beetle (Dendroctonus frontalis Ehrh.) (SPB) outbreaks in the upper South Carolina Piedmont. Prescribed burning and mastication were then tested as fuel reduction treatments in these areas. Prescribed burning reduced...

  10. compuestos fenólicos

    Directory of Open Access Journals (Sweden)

    Yolanda González García

    2005-01-01

    Full Text Available En este trabajo se presenta una revisión bibliográfica que tiene como objetivo identificar y analizar alternativas de aprovechamiento del bagazo de Agave tequilana Weber var. Azul. Se proponen dos líneas de investigación para obtener productos de valor agregado a partir de este residuo: 1utilización como fuente de carbono de bajo costo para la producción de biopolímeros y carbohidrasas, con bacterias celulolíticas del género Microbulbifer, Marinobacterium y Sagittula; 2obtención de compuestos fenólicos a partir de la lignina presente en sus fibras. Se concluye, que el bagazo de agave tequilero es un material viable para ser usado como substrato en procesos fermentativos, por lo que existen grandes oportunidades de investigación para desarrollar procesos de bioconversión técnicamente factible, eficiente y económicamente atractivo

  11. Specific growth rate plays a critical role in hydrogen peroxide resistance of the marine oligotrophic ultramicrobacterium Sphingomonas alaskensis strain RB2256

    NARCIS (Netherlands)

    Ostrowski, M; Cavicchioli, R; Gottschal, JC; Blaauw, Maarten

    The marine oligotrophic ultramicrobacterium Sphingomonas alaskensis RB2256 has a physiology that is distinctly different from that of typical copiotrophic marine bacteria, such as Vibrio angustum S14. This includes a high level of inherent stress resistance and the absence of starvation-induced

  12. Is lodgepole pine mortality due to mountain pine beetle linked to the North American Monsoon?

    Science.gov (United States)

    Sara A. Goeking; Greg C. Liknes

    2012-01-01

    Regional precipitation patterns may have influenced the spatial variability of tree mortality during the recent mountain pine beetle (Dendroctonus ponderosa) (MPB) outbreak in the western United States. Data from the Forest Inventory and Analysis (FIA) Program show that the outbreak was especially severe in the state of Colorado where over 10 million lodgepole pines (...

  13. Emissions of biogenic sulfur gases from northern bogs and fens

    Science.gov (United States)

    Demello, William Zamboni; Hines, Mark E.; Bayley, Suzanne E.

    1992-01-01

    Sulfur gases are important components of the global cycle of S. They contribute to the acidity of precipitation and they influence global radiation balance and climate. The role of terrestrial sources of biogenic S and their effect on atmospheric chemistry remain as major unanswered questions in our understanding of the natural S cycle. The role of northern wetlands as sources and sinks of gaseous S by measuring rates of S gas exchange as a function of season, hydrologic conditions, and gradients in tropic status was investigated. Experiments were conducted in wetlands in New Hampshire, particularly a poor fen, and in Mire 239, a poor fen at the Experimental Lakes Area (ELA) in Ontario. Emissions were determined using Teflon enclosures, gas cryotrapping methods and gas chromatography (GC) with flame photometric detection. Dynamic (sweep flow) and static enclosures were employed which yielded similar results. Dissolved S gases and methane were determined by gas stripping followed by GC.

  14. Successful Colonization of Lodgepole Pine Trees by Mountain Pine Beetle Increased Monoterpene Production and Exhausted Carbohydrate Reserves.

    Science.gov (United States)

    Roth, Marla; Hussain, Altaf; Cale, Jonathan A; Erbilgin, Nadir

    2018-02-01

    Lodgepole pine (Pinus contorta) forests have experienced severe mortality from mountain pine beetle (MPB) (Dendroctonus ponderosae Hopkins) in western North America for the last several years. Although the mechanisms by which beetles kill host trees are unclear, they are likely linked to pine defense monoterpenes that are synthesized from carbohydrate reserves. However, how carbohydrates and monoterpenes interact in response to MPB colonization is unknown. Understanding this relationship could help to elucidate how pines succumb to bark beetle attack. We compared concentrations of individual and total monoterpenes and carbohydrates in the phloem of healthy pine trees with those naturally colonized by MPB. Trees attacked by MPB had nearly 300% more monoterpenes and 40% less carbohydrates. Total monoterpene concentrations were most strongly associated with the concentration of sugars in the phloem. These results suggest that bark beetle colonization likely depletes carbohydrate reserves by increasing the production of carbon-rich monoterpenes, and other carbon-based secondary compounds. Bark beetle attacks also reduce water transport causing the disruption of carbon transport between tree foliage and roots, which restricts carbon assimilation. Reduction in carbohydrate reserves likely contributes to tree mortality.

  15. Lago Maggiore oligotrophication as seen from the long-term evolution of its phytoplankton taxonomic size structure

    Directory of Open Access Journals (Sweden)

    Giuseppe MORABITO

    2009-02-01

    Full Text Available Due to the rapid and common deterioration of aquatic ecosystems, scientists and environmental protection organizations acutely need means capable of producing quantitative estimates for structural deformations of natural communities. Recently, very common biomass size spectra ignore community taxonomic composition, i.e., one of the most important kinds of biological information. Therefore, another very old, but rare in planktonology, method – the traditional taxonomic size spectrum (TTSS – can be helpful. TTSS, a specific form of size-frequency distribution of taxonomic units, reveals repeating patterns of deep subalpine Lago Maggiore (Italy phytoplankton taxonomic structure. The general TTSS pattern was safeguarded during 22 annual cycles (1984-2005, when many principal environmental characteristics were changed considerably during the lake oligotrophication. At the same time, the fine structure deformations of this pattern helped us divide the total oligotrophication process into several stages characterized by notable changes of TTSS peaks' proportions. These peak-height alterations were caused by pronounced changes in the species list and overall taxonomic diversity of the lake phytoplankton. The average cell volume decline was found. It was significantly correlated with the total phosphorus descending trend. This cell volume decline was produced by the addition of numerous species into the medium-and-small size fractions. Typical patterns of the stable and transitory stages were differentiated, which could be valuable for environmental protection and diagnostic applications. The central peak height difference between the stable and the transitory periods was statistically significant. Oligotrophication process decomposition into several more homogenous groups of years was supported by quantitative estimators produced by hierarchical cluster analysis. The highest level of the similarity measure (Pearson r in pairs of annual TTSS was

  16. Comparisons of soil nitrogen mass balances for an ombrotrophic bog and a minerotrophic fen in northern Minnesota

    Science.gov (United States)

    Brian H. Hill; Terri M. Jicha; LaRae L.P. Lehto; Colleen M. Elonen; Stephen D. Sebestyen; Randy Kolka

    2016-01-01

    Wecompared nitrogen (N) storage and flux in soils froman ombrotrophic bogwith that of a minerotrophic fen to quantify the differences in N cycling between these two peatlands types in northernMinnesota (USA). Precipitation, atmospheric deposition, and bog and fen outflowswere analyzed for nitrogen species. Upland and peatland soil sampleswere analyzed for N content,...

  17. Mechanized row-thinning systems in slash pine plantations

    Science.gov (United States)

    Walter C. Anderson; James E. Granskog

    1974-01-01

    Over the next decade or two, most of the 15 to 20 million acres of pine plantations in the South will become ready for a first commercial thinning. The magnitude and nature of the job is illustrated by the situation in slash pine-the most extensively planted of the southern pines.

  18. Comparative Transcriptomics Among Four White Pine Species

    Directory of Open Access Journals (Sweden)

    Ethan A. G. Baker

    2018-05-01

    Full Text Available Conifers are the dominant plant species throughout the high latitude boreal forests as well as some lower latitude temperate forests of North America, Europe, and Asia. As such, they play an integral economic and ecological role across much of the world. This study focused on the characterization of needle transcriptomes from four ecologically important and understudied North American white pines within the Pinus subgenus Strobus. The populations of many Strobus species are challenged by native and introduced pathogens, native insects, and abiotic factors. RNA from the needles of western white pine (Pinus monticola, limber pine (Pinus flexilis, whitebark pine (Pinus albicaulis, and sugar pine (Pinus lambertiana was sampled, Illumina short read sequenced, and de novo assembled. The assembled transcripts and their subsequent structural and functional annotations were processed through custom pipelines to contend with the challenges of non-model organism transcriptome validation. Orthologous gene family analysis of over 58,000 translated transcripts, implemented through Tribe-MCL, estimated the shared and unique gene space among the four species. This revealed 2025 conserved gene families, of which 408 were aligned to estimate levels of divergence and reveal patterns of selection. Specific candidate genes previously associated with drought tolerance and white pine blister rust resistance in conifers were investigated.

  19. To live fast or not: growth, vigor and longevity of old-growth ponderosa pine and lodgepole pine trees

    Energy Technology Data Exchange (ETDEWEB)

    Kaufmann, M. R. [Forest Service, Fort Collins, CO (United States). Rocky Mountain Forest and Range Experiment Station

    1996-01-01

    Old ponderosa pine and lodgepole pine trees were studied to determine volume growth patterns in relation to leaf area. Ponderosa pine trees varied in age from 166 to 432 years and were about 77 inches in diameter; lodgepole pine trees ranged in age from 250 to 296 years and were 31 inches in diameter. Trees of both species had flat tops, heavy branches and foliage distribution characteristic of older trees. Annual volume increments were determined from crossdated radial increments measured on discs at four meter height intervals; leaf areas were determined based on leaf area/branch sapwood area ratios. Ponderosa pine volume growth was found to have been gradual at first, reaching a plateau that persisted for a century or more, followed by a rapid increase, and a sudden decrease in growth to less than one half of the earlier rate and persisting at these levels for several decades. In lodgepole pine growth decline was less frequent and less spectacular; growth in general was more even, with slight annual variations. Volume growth in the most recent years prior to felling weakly correlated with leaf area. Growth efficiencies were generally higher for trees having the lowest leaf areas. The fact that these persisted for many decades with low growth efficiencies suggests that defence mechanisms are more effective in old trees than in younger ones. 16 refs., 8 figs.

  20. The health of loblolly pine stands at Fort Benning, GA

    Science.gov (United States)

    Soung-Ryoul Ryu; G. Geoff Wang; Joan L. Walker

    2013-01-01

    Approximately two-thirds of the red-cockaded woodpecker (Picoides borealis) (RCW) groups at Fort Benning, GA, depend on loblolly pine (Pinus taeda) stands for nesting or foraging. However, loblolly pine stands are suspected to decline. Forest managers want to replace loblolly pine with longleaf pine (P. palustris...

  1. Ecosystem-based management in the lodgepole pine zone

    Science.gov (United States)

    Colin C. Hardy; Robert E. Keane; Catherine A. Stewart

    2000-01-01

    The significant geographic extent of lodgepole pine (Pinus contorta) in the interior West and the large proportion within the mixed-severity fire regime has led to efforts for more ecologically based management of lodgepole pine. New research and demonstration activities are presented that may provide knowledge and techniques to manage lodgepole pine...

  2. Foliar fungi of Scots pine (Pinus sylvestris)

    OpenAIRE

    Millberg, Hanna

    2015-01-01

    Scots pine (Pinus sylvestris) is an ecologically and economically important tree species in Fennoscandia. Scots pine needles host a variety of fungi, some with the potential to profoundly influence their host. These fungi can have beneficial or detrimental effects with important implications for both forest health and primary production. In this thesis, the foliar fungi of Scots pine needles were investigated with the aim of exploring spatial and temporal patterns, and development with needle...

  3. Fenóis totais, flavonoides totais e atividade antioxidante de Selaginella convoluta (Arn. Spring (Selaginellaceae

    Directory of Open Access Journals (Sweden)

    Pedro Guilherme Sousa de Sá

    2012-12-01

    Full Text Available Selaginella convoluta é uma espécie conhecida no Nordeste do Brasil como “jericó”, e bastante utilizada na medicina popular para tratamento de doenças. Este estudo teve como objetivo determinar o teor de compostos fenólicos e avaliar a atividade antioxidante in vitro do extrato etanólico e das frações obtidas por partição de S. convoluta. O conteúdo de fenóis totais foi determinado pelo método de Folin-Ciocalteu. O teor de flavonoides totais também foi avaliado. A atividade antioxidante dos extratos foi avaliada usando o método do sequestro do radical DPPH e inibição da auto-oxidação do sistema β-caroteno-ácido linoleico e comparada com os compostos de referência ácido ascórbico, BHA, BHT, quercetina e pirogalol. O conteúdo fenólico total foi de 209,90 ± 19,84 e 61,13 ± 2,50 mg equivalente de ácido gálico/g para os extratos AcOEt e EEB, respectivamente. O conteúdo de flavonoides totais foi de 155,70 ± 6,21 e 62,13 ± 4,10 para os dois extratos, respectivamente. Os extratos AcOEt e EEB apresentaram boas atividades antioxidantes. BHA foi o antioxidante mais efetivo, com um valor de IC50 de 1,62 ± 0,69 µg/mL. Os resultados obtidos mostram que S. convoluta pode ser uma boa fonte de compostos fenólicos antioxidantes. Estudos posteriores serão realizados para se chegar ao isolamento e identificação dos principais constituintes fenólicos dos extratos.

  4. Early longleaf pine seedling survivorship on hydric soils

    Science.gov (United States)

    Susan Cohen; Joan Walker

    2006-01-01

    We established a study to evaluate site preparation in restoring longleaf pine on poorly drained sites. Most existing longleaf pine stands occur on drier sites, and traditional approaches to restoring longleaf pine on wetter sites may rely on intensive practices that compromise the integrity of the ground layer vegetation. We applied silvicultural treatments to improve...

  5. Establishing Pine Monocultures and Mixed Pine-Hardwood Stands on Reclaimed Surface Mined Land in Eastern Kentucky: Implications for Forest Resilience in a Changing Climate

    Directory of Open Access Journals (Sweden)

    Geoffrey Bell

    2017-10-01

    Full Text Available Surface mining and mine reclamation practices have caused significant forest loss and forest fragmentation in Appalachia. Shortleaf pine (Pinus echinata is threatened by a variety of stresses, including diseases, pests, poor management, altered fire regimes, and climate change, and the species is the subject of a widescale restoration effort. Surface mines may present opportunity for shortleaf pine restoration; however, the survival and growth of shortleaf pine on these harsh sites has not been critically evaluated. This paper presents first-year survival and growth of native shortleaf pine planted on a reclaimed surface mine, compared to non-native loblolly pine (Pinus taeda, which has been highly successful in previous mined land reclamation plantings. Pine monoculture plots are also compared to pine-hardwood polyculture plots to evaluate effects of planting mix on tree growth and survival, as well as soil health. Initial survival of shortleaf pine is low (42%, but height growth is similar to that of loblolly pine. No differences in survival or growth were observed between monoculture and polyculture treatments. Additional surveys in coming years will address longer-term growth and survival patterns of these species, as well as changes to relevant soil health endpoints, such as soil carbon.

  6. Mechanisms controlling Cu, Fe, Mn, and Co profiles in peat of the Filson Creek Fen, northeastern Minnesota

    Science.gov (United States)

    Walton-Day, K.; Filipek, L.H.; Papp, C.S.E.

    1990-01-01

    Filson Creek Fen, located in northeastern Minnesota, overlies a Cu-Ni sulfide deposit. A site in the fen was studied to evaluate the hydrogeochemical mechanisms governing the development of Fe, Mn, Co, and Cu profiles in the peat. At the study site, surface peat approximately 1 m thick is separated from the underlying mineralized bedrock by a 6-12 m thickness of lake and glaciofluvial sediments and till. Concentrations of Fe, Mn, Co, and Cu in peat and major elements in pore water delineate a shallow, relatively oxidized, Cu-rich zone overlying a deeper, reduced, Fe-, Mn-, and Co-rich zone within the peat. Sequential metal extractions from peat samples reveal that 40-55% of the Cu in the shallow zone is associated with organic material, whereas the remaining Cu is distributed between iron-oxide, sulfide, and residual fractions. Sixty to seventy percent of the Fe, Mn, and Co concentrated in the deeper zone occur in the residual phase. The metal profiles and associations probably result from non-steady-state input of metals and detritus into the fen during formation of the peat column. The enrichment of organic-associated Cu in the upper, oxidized zone represents a combination of Cu transported into the fen with detrital plant fragments and soluble Cu, derived from weathering of outcrop and subcrop of the mineral deposit, transported into the fen, and fixed onto organic matter in the peat. The variable stratigraphy of the peat indicates that weathering processes and surface vegetation have changed through time in the fen. The Fe, Mn, and Co maxima at the base of the peat are associated with a maximum in detrital matter content of the peat resulting from a transition between the underlying inorganic sedimentary environment to an organic sedimentary environment. The chemistry of sediments and ground water collected beneath the peat indicate that mobilization of metals from sulfide minerals in the buried mineral deposit or glacial deposits is minimal. Therefore, the

  7. Cambial injury in lodgepole pine (Pinus contorta): mountain pine beetle vs fire.

    Science.gov (United States)

    Arbellay, Estelle; Daniels, Lori D; Mansfield, Shawn D; Chang, Alice S

    2017-12-01

    Both mountain pine beetle (MPB) Dendroctonus ponderosae Hopkins and fire leave scars with similar appearance on lodgepole pine Pinus contorta Dougl. ex Loud. var. latifolia Engelm. that have never been compared microscopically, despite the pressing need to determine the respective effects of MPB and fire injury on tree physiology. We analysed changes in wood formation in naturally caused scars on lodgepole pine, and tested the hypotheses that (i) MPB and fire injury elicit distinct anomalies in lodgepole pine wood and (ii) anomalies differ in magnitude and/or duration between MPB and fire. Mountain pine beetle and fire injury reduced radial growth in the first year post-injury. Otherwise, radial growth and wood density increased over more than 10 years in both MPB and fire scars. We found that the general increase in radial growth was of greater magnitude (up to 27%) and of longer duration (up to 5 years) in fire scars compared with MPB scars, as shown in earlywood width. We also observed that the increase in latewood density was of greater magnitude (by 12%) in MPB scars, but of longer duration (by 4 years) in fire scars. Crystallinity decreased following MPB and fire injury, while microfibril angle increased. These changes in fibre traits were of longer duration (up to 4 years) in MPB scars compared with fire scars, as shown in microfibril angle. We found no significant changes in carbon and nitrogen concentrations. In conclusion, we stress that reduced competition and resistance to cavitation play an important role alongside cambial injury in influencing the type and severity of changes. In addition, more research is needed to validate the thresholds introduced in this study. Our findings serve as a foundation for new protocols to distinguish between bark beetle and fire disturbance, which is essential for improving our knowledge of historical bark beetle and fire regimes, and their interactions. © The Author 2017. Published by Oxford University Press. All

  8. Diversity and decay ability of basidiomycetes isolated from lodgepole pines killed by the mountain pine beetle.

    Science.gov (United States)

    Son, E; Kim, J-J; Lim, Y W; Au-Yeung, T T; Yang, C Y H; Breuil, C

    2011-01-01

    When lodgepole pines (Pinus contorta Douglas ex Louden var. latifolia Engelm. ex S. Watson) that are killed by the mountain pine beetle (Dendroctonus ponderosae) and its fungal associates are not harvested, fungal decay can affect wood and fibre properties. Ophiostomatoids stain sapwood but do not affect the structural properties of wood. In contrast, white or brown decay basidiomycetes degrade wood. We isolated both staining and decay fungi from 300 lodgepole pine trees killed by mountain pine beetle at green, red, and grey stages at 10 sites across British Columbia. We retained 224 basidiomycete isolates that we classified into 34 species using morphological and physiological characteristics and rDNA large subunit sequences. The number of basidiomycete species varied from 4 to 14 species per site. We assessed the ability of these fungi to degrade both pine sapwood and heartwood using the soil jar decay test. The highest wood mass losses for both sapwood and heartwood were measured for the brown rot species Fomitopsis pinicola and the white rot Metulodontia and Ganoderma species. The sap rot species Trichaptum abietinum was more damaging for sapwood than for heartwood. A number of species caused more than 50% wood mass losses after 12 weeks at room temperature, suggesting that beetle-killed trees can rapidly lose market value due to degradation of wood structural components.

  9. Oligotrophic wetland sediments susceptible to shifts in microbiomes and mercury cycling with dissolved organic matter addition

    Directory of Open Access Journals (Sweden)

    Emily B. Graham

    2018-04-01

    Full Text Available Recent advances have allowed for greater investigation into microbial regulation of mercury toxicity in the environment. In wetlands in particular, dissolved organic matter (DOM may influence methylmercury (MeHg production both through chemical interactions and through substrate effects on microbiomes. We conducted microcosm experiments in two disparate wetland environments (oligotrophic unvegetated and high-C vegetated sediments to examine the impacts of plant leachate and inorganic mercury loadings (20 mg/L HgCl2 on microbiomes and MeHg production in the St. Louis River Estuary. Our research reveals the greater relative capacity for mercury methylation in vegetated over unvegetated sediments. Further, our work shows how mercury cycling in oligotrophic unvegetated sediments may be susceptible to DOM inputs in the St. Louis River Estuary: unvegetated microcosms receiving leachate produced substantially more MeHg than unamended microcosms. We also demonstrate (1 changes in microbiome structure towards Clostridia, (2 metagenomic shifts toward fermentation, and (3 degradation of complex DOM; all of which coincide with elevated net MeHg production in unvegetated microcosms receiving leachate. Together, our work shows the influence of wetland vegetation in controlling MeHg production in the Great Lakes region and provides evidence that this may be due to both enhanced microbial activity as well as differences in microbiome composition.

  10. Seasonal Trace Gas Dynamics on Minerotrophic Fen Peatlands in NE-Germany

    Science.gov (United States)

    Giebels, Michael; Beyer, Madlen; Augustin, Jürgen; Minke, Merten; Juszczak, Radoszlav; Serba, Tomasz

    2010-05-01

    In Germany more than 99 % of fens have lost their carbon and nutrient sink function due to heavy drainage and agricultural land use especially during the last decades and thus resulted in compression and heavy peat loss (CHARMAN 2002; JOOSTEN & CLARKE 2002; SUCCOW & JOOSTEN 2001; AUGUSTIN et al. 1996; KUNTZE 1993). Therefore fen peatlands play an important part (4-5 %) in the national anthropogenic trace gas budget. But only a small part of drained and agricultural used fens in NE Germany can be restored. Knowledge of the influence of land use to trace gas exchange is important for mitigation of the climate impact of the anthropogenic peatland use. We study carbon exchanges of several fen peatland use areas between soil and atmosphere at different sites in NE-Germany. Our research covers peatlands of supposed strongly climate forcing land use (cornfield and intensive pasture) and of probably less forcing, alternative types (meadow and extensive pasture) as well as rewetted (formerly drained) areas and near-natural sites like a low-degraded fen and a wetted alder woodland. We measured trace gas fluxes with manual and automatic chambers in periodic routines since spring 2007. The used chamber technique bases on DROESLER (2005). In total we now do research at 22 sites situated in 5 different locations covering agricultural, varying states of rewetted and near-natural treatments. We present results of at least 2 years of measurements and show significant differences in their annual trace gas balances depending on the genesis of the observed sites and the seasonal dynamics. Crosswise comparison of different site treatments combined with the seasonal environmental observations give good hints for the identification of main flux driving parameters. That is that a reduced intensity in land use as a supposed mitigating treatment did not show the expected effect, though a normal meadow treatment surprisingly resulted in the lowest balances in both years. For implementing a

  11. Seasonal Carbon Dynamics on Selected Fen Peatland Sites in NE-Germany

    Science.gov (United States)

    Giebels, Michael; Beyer, Madlen; Augustin, Jürgen; Minke, Merten; Juszczak, Radoszlav; Serba, Tomasz

    2010-05-01

    In Germany more than 99 % of fens have lost their carbon and nutrient sink function due to heavy drainage and agricultural land use especially during the last decades and thus resulted in compression and heavy peat loss (CHARMAN 2002; JOOSTEN & CLARKE 2002; SUCCOW & JOOSTEN 2001; AUGUSTIN et al. 1996; KUNTZE 1993). Therefore fen peatlands play an important part (4-5 %) in the national anthropogenic trace gas budget. But only a small part of drained and agricultural used fens in NE Germany can be restored. Knowledge of the influence of land use to trace gas exchange is important for mitigation of the climate impact of the anthropogenic peatland use. We study carbon exchanges of several fen peatland use areas between soil and atmosphere at different sites in NE-Germany. Our research covers peatlands of supposed strongly climate forcing land use (cornfield and intensive pasture) and of probably less forcing, alternative types (meadow and extensive pasture) as well as rewetted (formerly drained) areas and near-natural sites like a low-degraded fen and a wetted alder woodland. We measured trace gas fluxes with manual and automatic chambers in periodic routines since spring 2007. The used chamber technique bases on DROESLER (2005). In total we now do research at 22 sites situated in 5 different locations covering agricultural, varying states of rewetted and near-natural treatments. We present results of at least 2 years of measurements and show significant differences in their annual carbon balances depending on the genesis of the observed sites and the seasonal dynamics. Crosswise comparison of different site treatments combined with the seasonal environmental observations give good hints for the identification of main flux driving parameters. That is that a reduced intensity in land use as a supposed mitigating treatment did not show the expected effect, though a normal meadow treatment surprisingly resulted in the lowest CO2 balances in both years. For implementing a

  12. The Effect of Water Limitation on Volatile Emission, Tree Defense Response, and Brood Success of Dendroctonus ponderosae in Two Pine Hosts, Lodgepole, and Jack Pine

    OpenAIRE

    Lusebrink, Inka; Erbilgin, Nadir; Evenden, Maya L.

    2016-01-01

    The mountain pine beetle (MPB; Dendroctonus ponderosae) has recently expanded its range from lodgepole pine forest into the lodgepole × jack pine hybrid zone in central Alberta, within which it has attacked pure jack pine. This study tested the effects of water limitation on tree defense response of mature lodgepole and jack pine (Pinus contorta and Pinus banksiana) trees in the field. Tree defense response was initiated by inoculation of trees with the MPB-associated fungus Grosmannia clavig...

  13. Length Research Paper The effects of the pine processionary moth ...

    African Journals Online (AJOL)

    The pine processionary moth (PPM), causing significant damage on pine stands in Turkey, affects mainly crimean pine stands within the Ulus vicinity. To determine the damage, 20 sample plots of second site class crimean pine stands were measured; 10 of which were taken as the control sample and 10 of which were ...

  14. White pine blister rust resistance research in Minnesota and Wisconsin

    Science.gov (United States)

    Andrew David; Paul Berrang; Carrie Pike

    2012-01-01

    The exotic fungus Cronartium ribicola causes the disease white pine blister rust on five-needled pines throughout North America. Although the effects of this disease are perhaps better known on pines in the western portion of the continent, the disease has also impacted regeneration and growth of eastern white pine (Pinus strobus L. ...

  15. The most oligotrophic subtropical zones of the global ocean: similarities and differences in terms of chlorophyll and yellow substance

    Science.gov (United States)

    Morel, A.; Claustre, H.; Gentili, B.

    2010-10-01

    The cores of the subtropical anticyclonic gyres are characterized by their oligotrophic status and minimal chlorophyll concentration, compared to that of the whole ocean. These zones are unambiguously detected by space borne ocean color sensors thanks to their typical spectral reflectance, which is that of extremely clear and deep blue waters. Not only the low chlorophyll (denoted [Chl]) level, but also a reduced amount of colored dissolved organic matter (CDOM or "yellow substance") account for this clarity. The oligotrophic waters of the North and South Pacific gyres, the North and South Atlantic gyres, and the South Indian gyre have been comparatively studied with respect to both [Chl] and CDOM contents, by using 10-year data (1998-2007) of the Sea-viewing Wide field-of-view Sensor (SeaWiFS, NASA). Albeit similar these oligotrophic zones are not identical regarding their [Chl] and CDOM contents, as well as their seasonal cycles. According to the zone, the averaged [Chl] value varies from 0.026 to 0.059 mg m-3, whereas the ay(443) average (the absorption coefficient due to CDOM at 443 nm) is between 0.0033 and 0.0072 m-1. The CDOM-to-[Chl] relative proportions also differ between the zones. The clearest waters, corresponding to the lowest [Chl] and CDOM concentrations, are found near Easter Island and near Mariana Islands in the western part of the North Pacific Ocean. In spite of its low [Chl], the Sargasso Sea presents the highest CDOM content amongst the six zones studied. Except in the North Pacific gyre (near Mariana and south of Hawaii islands), a conspicuous seasonality appears to be the rule in the other 4 gyres and affects both [Chl] and CDOM; both quantities vary in a ratio of about 2 (maximum-to-minimum). Coinciding [Chl] and CDOM peaks occur just after the local winter solstice, which is also the period of the maximal mixed layer depth in these latitudes. It is hypothesized that the vertical transport of unbleached CDOM from the subthermocline layers

  16. Diversity of cultivated and metabolically active aerobic anoxygenic phototrophic bacteria along an oligotrophic gradient in the Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    C. Jeanthon

    2011-07-01

    Full Text Available Aerobic anoxygenic phototrophic (AAP bacteria play significant roles in the bacterioplankton productivity and biogeochemical cycles of the surface ocean. In this study, we applied both cultivation and mRNA-based molecular methods to explore the diversity of AAP bacteria along an oligotrophic gradient in the Mediterranean Sea in early summer 2008. Colony-forming units obtained on three different agar media were screened for the production of bacteriochlorophyll-a (BChl-a, the light-harvesting pigment of AAP bacteria. BChl-a-containing colonies represented a low part of the cultivable fraction. In total, 54 AAP strains were isolated and the phylogenetic analyses based on their 16S rRNA and pufM genes showed that they were all affiliated to the Alphaproteobacteria. The most frequently isolated strains belonged to Citromicrobium bathyomarinum, and Erythrobacter and Roseovarius species. Most other isolates were related to species not reported to produce BChl-a and/or may represent novel taxa. Direct extraction of RNA from seawater samples enabled the analysis of the expression of pufM, the gene coding for the M subunit of the reaction centre complex of aerobic anoxygenic photosynthesis. Clone libraries of pufM gene transcripts revealed that most phylotypes were highly similar to sequences previously recovered from the Mediterranean Sea and a large majority (~94 % was affiliated to the Gammaproteobacteria. The most abundantly detected phylotypes occurred in the western and eastern Mediterranean basins. However, some were exclusively detected in the eastern basin, reflecting the highest diversity of pufM transcripts observed in this ultra-oligotrophic region. To our knowledge, this is the first study to document extensively the diversity of AAP isolates and to unveil the active AAP community in an oligotrophic marine environment. By pointing out the discrepancies

  17. Forest development and carbon dynamics after mountain pine beetle outbreaks

    Science.gov (United States)

    E. Matthew. Hansen

    2014-01-01

    Mountain pine beetles periodically infest pine forests in western North America, killing many or most overstory pine stems. The surviving secondary stand structure, along with recruited seedlings, will form the future canopy. Thus, even-aged pine stands become multiaged and multistoried. The species composition of affected stands will depend on the presence of nonpines...

  18. Escaping the oligotrophic gyre? The year-round movements, foraging behaviour and habitat preferences of Murphy’s petrels

    OpenAIRE

    Clay, Thomas A.; Phillips, Richard A.; Manica, Andrea; Jackson, Hazel A.; Brooke, M. de L.

    2017-01-01

    The South Pacific Gyre is the world’s largest expanse of oligotrophic ocean and supports communities of endemic gadfly petrels Pterodroma spp., yet little is known about their foraging ecology in this nutrient-poor environment. We tracked Murphy’s petrels Pterodroma ultima with geolocators from Henderson Island, Pitcairn Islands, for 2 consecutive years (2011 to 2013). During pre-laying exodus, petrels travelled south and southwest of the colony, with males travelling further than females to ...

  19. Physicochemical and Sensory Properties of Whey Cheese with Pine Nuts

    Directory of Open Access Journals (Sweden)

    Cristina Anamaria Semeniuc

    2015-11-01

    Full Text Available This study aimed to develop a value-added whey cheese through addition of pine nuts. Therefore, different concentrations of pine nuts [2, 4, 6 and 8% (w/w] were added to whey cheese. The study was designed to evaluate the influence of pine nuts on physicochemical and sensory properties of whey cheese. The addition of pine nuts resulted in an increase in fat content and total solids and a decrease in moisture content. However, no statistically significant difference was found in pH values. Sensory analysis was performed using the 9-point hedonic scale, with selected assessors. The whey cheese sample with 4% pine nuts was the most appreciated (7.6 points, followed by the classic whey cheese, whey cheese with 6 and 8% pine nuts (7.4 points, and whey cheese with 2% pine nuts (7.3 points. Nevertheless, the sensory characteristics of whey cheese were not significantly influenced by the addition of pine nuts. Whey cheese sensory profiling was successful in differential characterization of whey cheese samples.

  20. Survey of microsatellite DNA in pine

    Science.gov (United States)

    Craig S. Echt; P. May-Marquardt

    1997-01-01

    A large insert genomic library from eastern white pine (Pinus strobus) was probed for the microsatellite motifs (AC)n and (AG)n, all 10 trinucleotide motifs, and 22 of the 33 possible tetranucleotide motifs. For comparison with a species from a different subgenus, a loblolly pine (Pinus taeda) genomic...

  1. Changing Land Use: The Fens of England. A Case Study in Land Reclamation [And] Student Work Book.

    Science.gov (United States)

    Laws, Kevin

    A social studies unit and student workbook explore changes in land use that have occurred in the Fenlands of England since the time it was first inhabited. Fens are lowlying land which is partially or completely covered with water. The English Fens are located on the eastern side of the British Isles and cover a total area of about 2,000 square…

  2. Mountain Pine Beetle Host Selection Between Lodgepole and Ponderosa Pines in the Southern Rocky Mountains.

    Science.gov (United States)

    West, Daniel R; Briggs, Jennifer S; Jacobi, William R; Negrón, José F

    2016-02-01

    Recent evidence of range expansion and host transition by mountain pine beetle (Dendroctonus ponderosae Hopkins; MPB) has suggested that MPB may not primarily breed in their natal host, but will switch hosts to an alternate tree species. As MPB populations expanded in lodgepole pine forests in the southern Rocky Mountains, we investigated the potential for movement into adjacent ponderosa pine forests. We conducted field and laboratory experiments to evaluate four aspects of MPB population dynamics and host selection behavior in the two hosts: emergence timing, sex ratios, host choice, and reproductive success. We found that peak MPB emergence from both hosts occurred simultaneously between late July and early August, and the sex ratio of emerging beetles did not differ between hosts. In two direct tests of MPB host selection, we identified a strong preference by MPB for ponderosa versus lodgepole pine. At field sites, we captured naturally emerging beetles from both natal hosts in choice arenas containing logs of both species. In the laboratory, we offered sections of bark and phloem from both species to individual insects in bioassays. In both tests, insects infested ponderosa over lodgepole pine at a ratio of almost 2:1, regardless of natal host species. Reproductive success (offspring/female) was similar in colonized logs of both hosts. Overall, our findings suggest that MPB may exhibit equally high rates of infestation and fecundity in an alternate host under favorable conditions. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Pines

    Science.gov (United States)

    C. Plomion; D. Chagne; D. Pot; S. Kumar; P.L. Wilcox; R.D. Burdon; D. Prat; D.G. Peterson; J. Paiva; P. Chaumeil; G.G. Vendramin; F. Sebastiani; C.D. Nelson; C.S. Echt; O. Savolainen; T.L. Kubisiak; M.T. Cervera; N. de Maria; M.N. Islam-Faridi

    2007-01-01

    Pinus is the most important genus within the Family Pinaceae and also within the gymnosperms by the number of species (109 species recognized by Farjon 2001) and by its contribution to forest ecosystems. All pine species are evergreen trees or shrubs. They are widely distributed in the northern hemisphere, from tropical areas to northern areas in America and Eurasia....

  4. Fire injury reduces inducible defenses of lodgepole pine against Mountain pine beetle.

    Science.gov (United States)

    Powell, Erinn N; Raffa, Kenneth F

    2011-11-01

    We examined the effect of wildfire injury on lodgepole pine chemical defenses against mountain pine beetle. We compared the constitutive phloem chemistry among uninjured, lightly-, moderately-, and severely-injured trees, and the induced chemistry elicited by simulated beetle attack, among these same categories. We also compared the entry rates of caged female beetles into trees of these categories. The volatiles we studied included thirteen monoterpene hydrocarbons, four allylic monoterpene alcohols, one ester, and one phenyl propanoid, of which the monoterpene hydrocarbons always comprised 96% or more of the total. Fire injury reduced the total concentration of these compounds in the induced but not constitutive phloem tissue of lodgepole pines. Fire injury also affected the relative composition of some volatiles in both induced and constitutive phloem. For example, increased fire injury reduced 4-allylanisole, a host compound that inhibits mountain pine beetle aggregation. Increased fire injury also increased (-) α-pinene, which can serve as precursor of pheromone communication. However, it also reduced myrcene and terpinolene, which can serve as stimulants and synergists of pheromone communication. Beetle entry did not show statistical differences among fire injury categories, although there was a trend to increased entry with fire injury. These results suggest that the reduced ability of trees to mobilize induced chemical defenses is an important mechanism behind the higher incidence of attack on fire-injured trees in the field. Future studies should concentrate on whether beetles that enter fire-injured trees are more likely to elicit aggregation, based on the differences we observed in volatile composition.

  5. Effects of dwarf mistletoe on stand structure of lodgepole pine forests 21-28 years post-mountain pine beetle epidemic in central Oregon

    Science.gov (United States)

    Michelle C. Agne; David C. Shaw; Travis J. Woolley; Mónica E. Queijeiro-Bolaños; Mai-He. Li

    2014-01-01

    Lodgepole pine (Pinus contorta) forests are widely distributed throughout North America and are subject to mountain pine beetle (Dendroctonus ponderosae) epidemics, which have caused mortality over millions of hectares of mature trees in recent decades. Mountain pine beetle is known to influence stand structure, and has the ability to impact many forest processes....

  6. Microbial Communities as Environmental Indicators of Ecological Disturbance in Restored Carbonate Fen-Results of 10 Years of Studies.

    Science.gov (United States)

    Mieczan, Tomasz; Tarkowska-Kukuryk, Monika

    2017-08-01

    Interactions between bacteria and protists are essential to the ecosystem ecology of fens. Until now, however, there has been almost no information on how restoration procedures in carbonate fens affect the functioning of microbial food webs. Changes in vegetation patterns resulting from restoration may take years to be observed, whereas microbial processes display effects even after short-term exposure to changes in environmental conditions caused by restoration. Therefore, microbial processes and patterns can be used as sensitive indicators of changes in environmental conditions. The present study attempts to verify the hypothesis that the species richness and abundance of microbial loop components would differ substantially before and after restoration. The effect of restoration processes on the functioning of the food web was investigated for a 10 years in a carbonate-rich fen, before and after restoration. The restoration procedure (particularly the improvement in hydrological conditions) distinctly modified the taxonomic composition and functioning of microbial food webs. This is reflected in the increased abundance and diversity of testate amoeba, i.e. top predators, within the microbial food web and in the pronounced increase in the abundance of bacteria. This study suggests potential use of microbial loop components as bio-indicators and bio-monitoring tools for hydrological status of fens and concentrations of nutrients. Better understanding of what regulates microbial populations and activity in fens and unravelling of these fundamental mechanisms are particularly critical in order to more accurately predict how fens will respond to global change or anthropogenic disturbances.

  7. Geographic variation in shortleaf pine (Pinus echinata Mill.) - cortical monoterpenes

    Science.gov (United States)

    R.C. Schmidtling; J.H. Myszewski; C.E. McDaniel

    2005-01-01

    Cortical monoterpenes were assayed in bud tissue from 16 Southwide Southern Pine Seed Source Study (SSPSS) sources and from 6 seed orchard sources fiom across the natural range of the species, to examine geogaphic variation in shortleaf pine. Spruce pine and pond pine were also sampled. The results show geographic differences in all of the major terpenes. There was no...

  8. Xylem monoterpenes of pines: distribution, variation, genetics, function

    Science.gov (United States)

    Richard Smith

    2000-01-01

    The monoterpenes of about 16,000 xylem resin samples of pine (Pinus) speciesand hybrids—largely from the western United States—were analyzed in this long-term study of the resistance of pines to attack by bark beetles (Coleoptera:Scolytidae), with special emphasis on resistance to the western pine beetle(Dendroctonus brevicomis). The samples were analyzed by gas liquid...

  9. Pine growth and plant community response to chemical vs. mechanical site preparation for establishing loblolly and slash pine

    Science.gov (United States)

    James H. Miller; Zhijuan Qiu

    1995-01-01

    Chemical and mechanical site preparation methods were studied for establishing loblolly (Pinus taeda L) and slash (P. elliottii var. elliottii Engelm.) pine following both integrated fuelwood-pulpwood harvesting and conventional whole-tree harvesting of pines and hardwoods in southem Alabama's Middle Coastal...

  10. Pine Gene Discovery Project - Final Report - 08/31/1997 - 02/28/2001; FINAL

    International Nuclear Information System (INIS)

    Whetten, R. W.; Sederoff, R. R.; Kinlaw, C.; Retzel, E.

    2001-01-01

    Integration of pines into the large scope of plant biology research depends on study of pines in parallel with study of annual plants, and on availability of research materials from pine to plant biologists interested in comparing pine with annual plant systems. The objectives of the Pine Gene Discovery Project were to obtain 10,000 partial DNA sequences of genes expressed in loblolly pine, to determine which of those pine genes were similar to known genes from other organisms, and to make the DNA sequences and isolated pine genes available to plant researchers to stimulate integration of pines into the wider scope of plant biology research. Those objectives have been completed, and the results are available to the public. Requests for pine genes have been received from a number of laboratories that would otherwise not have included pine in their research, indicating that progress is being made toward the goal of integrating pine research into the larger molecular biology research community

  11. Diverse gene cassettes in class 1 integrons of facultative oligotrophic bacteria of River Mahananda,West Bengal, India.

    Directory of Open Access Journals (Sweden)

    Ranadhir Chakraborty

    Full Text Available BACKGROUND: In this study a large random collection (n=2188 of facultative oligotrophic bacteria, from 90 water samples gathered in three consecutive years (2007-2009 from three different sampling sites of River Mahananda in Siliguri, West Bengal, India, were investigated for the presence of class 1 integrons and sequences of the amplification products. METHODOLOGY/PRINCIPAL FINDINGS: Replica plating method was employed for determining the antibiotic resistance profile of the randomly assorted facultative oligotrophic isolates. Genomic DNA from each isolate was analyzed by PCR for the presence of class 1 integron. Amplicons were cloned and sequenced. Numerical taxonomy and 16S rRNA gene sequence analyses were done to ascertain putative genera of the class 1 integron bearing isolates. Out of 2188 isolates, 1667 (76.19% were antibiotic-resistant comprising of both single-antibiotic resistance (SAR and multiple-antibiotic resistant (MAR, and 521 (23.81% were sensitive to all twelve different antibiotics used in this study. Ninety out of 2188 isolates produced amplicon(s of varying sizes from 0.15 to 3.45 KB. Chi-square (χ(2 test revealed that the possession of class 1 integron in sensitive, SAR and MAR is not equally probable at the 1% level of significance. Diverse antibiotic-resistance gene cassettes, aadA1, aadA2, aadA4, aadA5, dfrA1, dfrA5, dfrA7, dfrA12, dfrA16, dfrA17, dfrA28, dfrA30, dfr-IIe, blaIMP-9, aacA4, Ac-6'-Ib, oxa1, oxa10 and arr2 were detected in 64 isolates. The novel cassettes encoding proteins unrelated to any known antibiotic resistance gene function were identified in 26 isolates. Antibiotic-sensitive isolates have a greater propensity to carry gene cassettes unrelated to known antibiotic-resistance genes. The integron-positive isolates under the class Betaproteobacteria comprised of only two genera, Comamonas and Acidovorax of family Comamonadaceae, while isolates under class Gammaproteobacteria fell under the families

  12. The response of soil organic carbon of a rich fen peatland in interior Alaska to projected climate change.

    Science.gov (United States)

    Fan, Zhaosheng; David McGuire, Anthony; Turetsky, Merritt R; Harden, Jennifer W; Michael Waddington, James; Kane, Evan S

    2013-02-01

    It is important to understand the fate of carbon in boreal peatland soils in response to climate change because a substantial change in release of this carbon as CO2 and CH4 could influence the climate system. The goal of this research was to synthesize the results of a field water table manipulation experiment conducted in a boreal rich fen into a process-based model to understand how soil organic carbon (SOC) of the rich fen might respond to projected climate change. This model, the peatland version of the dynamic organic soil Terrestrial Ecosystem Model (peatland DOS-TEM), was calibrated with data collected during 2005-2011 from the control treatment of a boreal rich fen in the Alaska Peatland Experiment (APEX). The performance of the model was validated with the experimental data measured from the raised and lowered water-table treatments of APEX during the same period. The model was then applied to simulate future SOC dynamics of the rich fen control site under various CO2 emission scenarios. The results across these emissions scenarios suggest that the rate of SOC sequestration in the rich fen will increase between year 2012 and 2061 because the effects of warming increase heterotrophic respiration less than they increase carbon inputs via production. However, after 2061, the rate of SOC sequestration will be weakened and, as a result, the rich fen will likely become a carbon source to the atmosphere between 2062 and 2099. During this period, the effects of projected warming increase respiration so that it is greater than carbon inputs via production. Although changes in precipitation alone had relatively little effect on the dynamics of SOC, changes in precipitation did interact with warming to influence SOC dynamics for some climate scenarios. © 2012 Blackwell Publishing Ltd.

  13. The response of soil organic carbon of a rich fen peatland in interior Alaska to projected climate change

    Science.gov (United States)

    Fan, Zhaosheng; McGuire, Anthony David; Turetsky, Merritt R.; Harden, Jennifer W.; Waddington, James Michael; Kane, Evan S.

    2013-01-01

    It is important to understand the fate of carbon in boreal peatland soils in response to climate change because a substantial change in release of this carbon as CO2 and CH4 could influence the climate system. The goal of this research was to synthesize the results of a field water table manipulation experiment conducted in a boreal rich fen into a process-based model to understand how soil organic carbon (SOC) of the rich fen might respond to projected climate change. This model, the peatland version of the dynamic organic soil Terrestrial Ecosystem Model (peatland DOS-TEM), was calibrated with data collected during 2005–2011 from the control treatment of a boreal rich fen in the Alaska Peatland Experiment (APEX). The performance of the model was validated with the experimental data measured from the raised and lowered water-table treatments of APEX during the same period. The model was then applied to simulate future SOC dynamics of the rich fen control site under various CO2 emission scenarios. The results across these emissions scenarios suggest that the rate of SOC sequestration in the rich fen will increase between year 2012 and 2061 because the effects of warming increase heterotrophic respiration less than they increase carbon inputs via production. However, after 2061, the rate of SOC sequestration will be weakened and, as a result, the rich fen will likely become a carbon source to the atmosphere between 2062 and 2099. During this period, the effects of projected warming increase respiration so that it is greater than carbon inputs via production. Although changes in precipitation alone had relatively little effect on the dynamics of SOC, changes in precipitation did interact with warming to influence SOC dynamics for some climate scenarios.

  14. The legacy of attack: implications of high phloem resin monoterpene levels in lodgepole pines following mass attack by mountain pine beetle, Dendroctonus ponderosae Hopkins.

    Science.gov (United States)

    Clark, E L; Huber, D P W; Carroll, A L

    2012-04-01

    The mountain pine beetle (Dendroctonus ponderosae Hopkins) is the most serious pest of pines (Pinus) in western North America. Host pines protect themselves from attack by producing a complex mixture of terpenes in their resin. We sampled lodgepole pine (Pinus contorta variety latifolia) phloem resin at four widely separated locations in the interior of British Columbia, Canada, both just before (beginning of July) and substantially after (end of August) the mountain pine beetle dispersal period. The sampled trees then were observed the next spring for evidence of survival, and the levels of seven resin monoterpenes were compared between July and August samples. Trees that did not survive consistently had significantly higher phloem resin monoterpene levels at the end of August compared with levels in July. Trees that did survive mainly did not exhibit a significant difference between the two sample dates. The accumulation of copious defense-related secondary metabolites in the resin of mountain pine beetle-killed lodgepole pine has important implications for describing the environmental niche that the beetle offspring survive in as well as that of parasitoids, predators, and other associates.

  15. Fen Bilgisi Öğretmen Adaylarının Kimya Bilgilerini Günlük Hayatla İlişkilendirebilme Düzeyleri

    OpenAIRE

    Yadigaroğlu, Yrd. Doç. Dr. Mustafa; DEMİRCİOĞLU, Doç. Dr. Gökhan; DEMİRCİOĞLU, Doç. Dr. Hülya

    2017-01-01

    Fen eğitiminin temel amaçlarındanbiri, öğrencilerin fen okur-yazarı olmalarını sağlayarak onları günlükyaşantılarında karşılaştıkları fen olaylarına anlam vermelerine yardımcıolmaktır. Günlük hayatla ya da bağlamı ile ilişkilendirilmeyen bilgi öğrencininzihninde her zaman eksik olacaktır. Bunun gerçekleştirilmesinde fen dersleriiçerisinde yer alan kimya önemli bir yere sahiptir. Bu düşünceden hareketleçalışmada, fen bilgisi öğretmen adaylarının kimya bilgilerini günlük hayatlailişkilendirebil...

  16. Mountain pine beetle infestation: GCxGCTOFMS and GC-MS of lodgepole pine (pinus contorta) acetone extractives

    Science.gov (United States)

    Roderquita K. Moore; Michael Leitch; Erick Arellano-ruiz; Jonathon Smaglick; Doreen Mann

    2015-01-01

    The Rocky Mountains and western U.S. forests are impacted by the infestation of mountain pine beetles (MPB). MPB outbreak is killing pine and spruce trees at an alarming rate. These trees present a fuel build-up in the forest, which can result in catastrophic wildland fires. MPB carry blue-stain fungi from the genus Ophiostoma and transmit infection by burrowing into...

  17. The distribution and migration of sodium from a reclaimed upland to a constructed fen peatland in a post-mined oil sands landscape.

    Science.gov (United States)

    Kessel, Eric D; Ketcheson, Scott J; Price, Jonathan S

    2018-07-15

    Post-mine landscape reclamation of the Athabasca Oil Sands Region requires the use of tailings sand, an abundant mine-waste material that often contains large amounts of sodium (Na + ). Due to the mobility of Na + in groundwater and its effects on vegetation, water quality is a concern when incorporating mine waste materials, especially when attempting to construct groundwater-fed peatlands. This research is the first published account of Na + redistribution in groundwater from a constructed tailings sand upland to an adjacent constructed fen peat deposit (Nikanotee Fen). A permeable petroleum coke layer underlying the fen, extending partway into the upland, was important in directing flow and Na + beneath the peat, as designed. Initially, Na + concentration was highest in the tailings sand (average of 232mgL -1 ) and lowest in fen peat (96mgL -1 ). Precipitation-driven recharge to the upland controlled the mass flux of Na from upland to fen, which ranged from 2 to 13tons Na + per year. The mass flux was highest in the driest summer, in part from dry-period flowpaths that direct groundwater with higher concentrations of Na + into the coke layer, and in part because of the high evapotranspiration loss from the fen in dry periods, which induces upward water flow. With the estimated flux rates of 336mmyr -1 , the Na + arrival time to the fen surface was estimated to be between 4 and 11years. Over the four-year study, average Na + concentrations within the fen rooting zone increased from 87 to 200mgL -1 , and in the tailings sand decreased to 196mgL -1 . The planting of more salt-tolerant vegetation in the fen is recommended, given the potential for Na + accumulation. This study shows reclamation designs can use layered flow system to control the rate, pattern, and timing of solute interactions with surface soil systems. Crown Copyright © 2018. Published by Elsevier B.V. All rights reserved.

  18. Soil properties in 35 y old pine and hardwood plantations after conversion from mixed pine-hardwood forest

    Science.gov (United States)

    D. Andrew Scott; Michael G. Messina

    2009-01-01

    Past management practices have changed much of the native mixed pine-hardwood forests on upland alluvial terraces of the western Gulf Coastal Plain to either pine monocultures or hardwood (angiosperm) stands. Changes in dominant tree species can alter soil chemical, biological, and physical properties and processes, thereby changing soil attributes, and ultimately,...

  19. Para Além do Estado e do Mercado: A Dádiva no Fenômeno dos Sem-Abrigo

    Directory of Open Access Journals (Sweden)

    João Aldeia

    2014-03-01

    Full Text Available Las reflexiones sobre el fenómeno de los sin techo tienden a reproducir las ausencias que el paradigma del don identifica en el pensamiento sobre las sociedades modernas occidentales. Recurrentemente, se considera al Estado y al mercado como las únicas esferas de regulación social y se los interpreta como los espacios de donde derivan las causas estructurales y las posibles soluciones para el fenómeno. Ello no permite una comprensión completa del tema y tampoco una reflexión consistente sobre los modos de minimizar las injusticias de la vida en la calle. Pensar sobre el fenómeno por medio del paradigma del don es relevante porque permite identificar la habitual invisibilización de las relaciones interpersonales no oficiales que caracterizan la vida en la calle, posibilitando, a su vez, la revalorización de estas interacciones en el debate sobre el fenómeno de los sin techo.

  20. Nitrogen cycling responses to mountain pine beetle disturbance in a high elevation whitebark pine ecosystem.

    Science.gov (United States)

    Keville, Megan P; Reed, Sasha C; Cleveland, Cory C

    2013-01-01

    Ecological disturbances can significantly affect biogeochemical cycles in terrestrial ecosystems, but the biogeochemical consequences of the extensive mountain pine beetle outbreak in high elevation whitebark pine (WbP) (Pinus albicaulis) ecosystems of western North America have not been previously investigated. Mountain pine beetle attack has driven widespread WbP mortality, which could drive shifts in both the pools and fluxes of nitrogen (N) within these ecosystems. Because N availability can limit forest regrowth, understanding how beetle-induced mortality affects N cycling in WbP stands may be critical to understanding the trajectory of ecosystem recovery. Thus, we measured above- and belowground N pools and fluxes for trees representing three different times since beetle attack, including unattacked trees. Litterfall N inputs were more than ten times higher under recently attacked trees compared to unattacked trees. Soil inorganic N concentrations also increased following beetle attack, potentially driven by a more than two-fold increase in ammonium (NH₄⁺) concentrations in the surface soil organic horizon. However, there were no significant differences in mineral soil inorganic N or soil microbial biomass N concentrations between attacked and unattacked trees, implying that short-term changes in N cycling in response to the initial stages of WbP attack were restricted to the organic horizon. Our results suggest that while mountain pine beetle attack drives a pulse of N from the canopy to the forest floor, changes in litterfall quality and quantity do not have profound effects on soil biogeochemical cycling, at least in the short-term. However, continuous observation of these important ecosystems will be crucial to determining the long-term biogeochemical effects of mountain pine beetle outbreaks.

  1. Nitrogen cycling responses to mountain pine beetle disturbance in a high elevation whitebark pine ecosystem

    Science.gov (United States)

    Keville, Megan P.; Reed, Sasha C.; Cleveland, Cory C.

    2013-01-01

    Ecological disturbances can significantly affect biogeochemical cycles in terrestrial ecosystems, but the biogeochemical consequences of the extensive mountain pine beetle outbreak in high elevation whitebark pine (WbP) (Pinus albicaulis) ecosystems of western North America have not been previously investigated. Mountain pine beetle attack has driven widespread WbP mortality, which could drive shifts in both the pools and fluxes of nitrogen (N) within these ecosystems. Because N availability can limit forest regrowth, understanding how beetle-induced mortality affects N cycling in WbP stands may be critical to understanding the trajectory of ecosystem recovery. Thus, we measured above- and belowground N pools and fluxes for trees representing three different times since beetle attack, including unattacked trees. Litterfall N inputs were more than ten times higher under recently attacked trees compared to unattacked trees. Soil inorganic N concentrations also increased following beetle attack, potentially driven by a more than two-fold increase in ammonium (NH4+) concentrations in the surface soil organic horizon. However, there were no significant differences in mineral soil inorganic N or soil microbial biomass N concentrations between attacked and unattacked trees, implying that short-term changes in N cycling in response to the initial stages of WbP attack were restricted to the organic horizon. Our results suggest that while mountain pine beetle attack drives a pulse of N from the canopy to the forest floor, changes in litterfall quality and quantity do not have profound effects on soil biogeochemical cycling, at least in the short-term. However, continuous observation of these important ecosystems will be crucial to determining the long-term biogeochemical effects of mountain pine beetle outbreaks.

  2. Human FEN1 Expression and Solubility Patterson in DNA Replication and Repair

    National Research Council Canada - National Science Library

    Carrier, Richard

    1999-01-01

    Flap endo-/exonuclease (FEN1) is a highly conserved protein shown to be one of 10 essential human proteins required for the production of form I DNA following DNA replication from the simian virus 40 (SV40...

  3. Repeated Raking of Pine Plantations Alters Soil Arthropod Communities

    Directory of Open Access Journals (Sweden)

    Holly K. Ober

    2014-04-01

    Full Text Available Terrestrial arthropods in forests are engaged in vital ecosystem functions that ultimately help maintain soil productivity. Repeated disturbance can cause abrupt and irreversible changes in arthropod community composition and thereby alter trophic interactions among soil fauna. An increasingly popular means of generating income from pine plantations in the Southeastern U.S. is annual raking to collect pine litter. We raked litter once per year for three consecutive years in the pine plantations of three different species (loblolly, Pinus taeda; longleaf, P. palustris; and slash, P. elliottii. We sampled arthropods quarterly for three years in raked and un-raked pine stands to assess temporal shifts in abundance among dominant orders of arthropods. Effects varied greatly among orders of arthropods, among timber types, and among years. Distinct trends over time were apparent among orders that occupied both high trophic positions (predators and low trophic positions (fungivores, detritivores. Multivariate analyses demonstrated that raking caused stronger shifts in arthropod community composition in longleaf and loblolly than slash pine stands. Results highlight the role of pine litter in shaping terrestrial arthropod communities, and imply that repeated removal of pine straw during consecutive years is likely to have unintended consequences on arthropod communities that exacerbate over time.

  4. Seed release in serotinous lodgepole pine forests after mountain pine beetle outbreak.

    Science.gov (United States)

    Teste, François P; Lieffers, Victor J; Landhausser, Simon M

    2011-01-01

    There are concerns that large-scale stand mortality due to mountain pine beetle (MPB) could greatly reduce natural regeneration of serotinous Rocky Mountain (RM) lodgepole pine (Pinus contorta var. latifolia) because the closed cones are held in place without the fire cue for cone opening. We selected 20 stands (five stands each of live [control], 3 years since MPB [3-yr-MPB], 6 years since MPB [6-yr-MPB], and 9 years since MPB [9-yr-MPB] mortality) in north central British Columbia, Canada. The goal was to determine partial loss of serotiny due to fall of crown-stored cones via breakage of branches and in situ opening of canopy cones throughout the 2008 and 2009 growing seasons. We also quantified seed release by the opening of forest-floor cones, loss of seed from rodent predation, and cone burial. Trees killed by MPB three years earlier dropped approximately 3.5 times more cones via branch breakage compared to live stands. After six years, MPB-killed stands had released 45% of their canopy seed bank through cone opening, cone fall due to breakage, and squirrel predation. Further losses of canopy seed banks are expected with time since we found 9-yr-MPB stands had 38% more open canopy cones. This was countered by the development of a modest forest-floor seed bank (6% of the original canopy seed bank) from burial of cones; this seed bank may be ecologically important if a fire or anthropogenic disturbance reexposes these cones. If adequate levels of regeneration are to occur, disturbances to create seedbeds must occur shortly after tree mortality, before the seed banks are lost. Our findings also suggest that the sustained seed rain (over at least nine years) after MPB outbreak may be beneficial for population growth of ground-foraging vertebrates. Our study adds insight to the seed ecology of serotinous pines under a potentially continental-wide insect outbreak, threatening vast forests adapted to regeneration after fire. Key words: biotic disturbance; cone

  5. Documentation and user guides for SPBLOB: a computer simulation model of the join population dynamics for loblolly pine and the southern pine beetle

    Science.gov (United States)

    John Bishir; James Roberds; Brian Strom; Xiaohai Wan

    2009-01-01

    SPLOB is a computer simulation model for the interaction between loblolly pine (Pinus taeda L.), the economically most important forest crop in the United States, and the southern pine beetle (SPB: Dendroctonus frontalis Zimm.), the major insect pest for this species. The model simulates loblolly pine stands from time of planting...

  6. Prey handling and diet of Louisiana pine snakes (Pituophis ruthveni) and black pine snakes (P. melanoleucus lodingi), with comparisons to other selected colubrid snakes

    Science.gov (United States)

    D. Craig Rudolph; Shirley J. Burgdorf; Richard N. Conner; Christopher S. Collins; Daniel Saenz; Richard R. Schaefer; Toni Trees; C. Michael Duran; Marc Ealy; John G. Himes

    2002-01-01

    Diet and prey handling behavior were determined for Louisiana pine snakes (Pituophis ruthveni) and black pine snakes (P. melanoleucus lodingi). Louisiana pine snakes prey heavily on Baird's pocket gophers (Geomys breviceps), with which they are sympatric, and exhibit specialized behaviors that facilitate...

  7. Biochemical Assay Detects Feeding Damage to Loblolly Pine Seeds Caused by the Leaffooted Pine Seed Bug (Hemiptera: Coreidae)

    Science.gov (United States)

    Cameron G. Lait; Daniel R. Miller; Sarah L. Bates; John H. Borden; Allison R. Kermode

    2003-01-01

    A large number of proteins in salivary gland extracts of the leaffooted pine seed bug, Leptoglossus corculus Say, were strongly recognized by a polyclonal antibody-based assay developed for detecting saliva of the western conifer seed bug, Lepfoglossus occidentalis Heidemann, in lodgepole pine, Pinus contorta var...

  8. Development of merchantable volume equations for natural brutian pine and black pine stands in Eğirdir District

    Directory of Open Access Journals (Sweden)

    Ramazan Özçelik

    2016-01-01

    Full Text Available Determination of stem standing volume is very useful for both sustainable management of timber resources and practical purposes in forestry. Brutian pine (Pinus brutia Ten. and black pine (Pinus nigra Arnold. are important raw material of forest products industry of Turkey. With ever changing market conditions, there is a need to accurately estimate tree volumes utilizing multiple upper stem merchantability limits. This is not currently possible with the existing total stem volume tables for these three species. Nowadays, taper equations are the best way to estimate volume for saw timber and biomass purposes. In this study, variable exponent taper equations evaluated and fitted to data come from 253 destructively sampled trees which were collected in natural brutian pine and black pine stands in Eğirdir district. For this aim, the taper equations of Lee et al. (2003, Kozak (2004, and Sharma and Zhang (2004 were used. A second-order continuous-time autoregressive error structure was used to correct the inherent autocorrelation in the hierarchical data. The proposed models generally performed better for Merchantable tree volume. Results show that the Kozak (2004 taper equation was superior to the other equations in predicting diameter and merchantable height, while The Sharma and Zhang (2004 taper model provided the best predictions for merchantable volume than the other models. The one of the important results of this study, the importance of checking fit statistics of taper equations for both diameters and volume estimations.As a results, Sharma and Zhang (2004 taper model recommended for estimating diameter at a specific height, height to a specific diameter along the stem, and merchantable volume for brutian pine and black pine stands in Eğirdir analyzed

  9. High elevation white pines educational website

    Science.gov (United States)

    Anna W. Schoettle; Michele Laskowski

    2011-01-01

    The high elevation five-needle white pines are facing numerous challenges ranging from climate change to invasion by a non-native pathogen to escalation of pest outbreaks. This website (http://www.fs.fed.us/rm/highelevationwhitepines/) serves as a primer for managers and the public on the high elevation North American five-needle pines. It presents information on each...

  10. The effect of an exceptionally wet summer on methane effluxes from a 15-year re-wetted fen in north-east Germany

    Directory of Open Access Journals (Sweden)

    V. Huth

    2013-10-01

    Full Text Available Re-wetting minerotrophic fens has become an important strategy to mitigate climate change in Germany. However, recent studies report raised methane (CH4 effluxes during the first years after flooding. A minerotrophic fen in north-east Germany that was re-wetted 15 years ago was exposed to exceptionally heavy rainfall and freshwater flooding in August 2011. We measured CH4 effluxes from wetland vegetation stands dominated by Phragmites australis (Cav. Trin. ex Steud., Typha latifolia L. and Carex acutiformis Ehrh., using the closed-chamber method, fortnightly from March 2011 to March 2012 with extra sampling during the flooding. The respective annual effluxes of CH4 (mean ± 1 standard error from the three vegetation types were 18.5 ± 1.3, 21.1 ± 1.2 and 47.5 ± 5.0 g m-2 a-1, with the August effluxes contributing 40 %, 50 % and 10 % of the annual effluxes. Despite the freshwater flooding in August, annual CH4 effluxes from the 15-year re-wetted fen are similar to those reported from pristine fens. These results are promising because they indicate that, although CH4 effluxes are elevated after re-wetting, they may return to values typical for pristine fens after 15 years. Hence, re-wetting can achieve the purpose of reducing greenhouse gas effluxes from drained minerotrophic fens.

  11. Human FEN1 Expression and Solubility Patterson in DNA Replication and Repair

    National Research Council Canada - National Science Library

    Carrier, Richard

    1999-01-01

    .... I show that human FEN1 mRNA and protein levels increase in a cell cycle-dependent manner, with peak mRNA and protein levels attained coincident with S phase DNA replication in both primary and transformed cells...

  12. White pines, Ribes, and blister rust: integration and action

    Science.gov (United States)

    R. S. Hunt; B. W. Geils; K. E. Hummer

    2010-01-01

    The preceding articles in this series review the history, biology and management of white pine blister rust in North America, Europe and eastern Asia. In this integration, we connect and discuss seven recurring themes important for understanding and managing epidemics of Cronartium ribicola in the white pines (five-needle pines in subgenus Strobus). Information and...

  13. Large deficiency of polonium in the oligotrophic ocean's interior

    Science.gov (United States)

    Kim, Guebuem

    2001-09-01

    The naturally occurring radionuclide 210Po is typically deficient relative to its parent 210Pb in the surface ocean due to preferential removal by biota, while in near equilibrium or excess below the surface mixed layer due to rapid regeneration from sinking organic matter. However, a strikingly large deficit of 210Po is observed in the oligotrophic Sargasso Sea's interior. This argues against the general concept that the removal of reactive elements depends on the population of settling particles. A 210Po mass balance model suggests that rather than downward transport, polonium (proxy for S, Se, and Te) is taken up efficiently by bacteria (i.e., cyanobacteria) and transferred to higher trophic levels (i.e., nekton) in this environment. In contrast, in productive areas of the ocean, sulfur group elements seem to reside in the subsurface ocean for much longer periods as taken up by abundant free-living bacteria (non-sinking fine particles). This study sheds new light on global biogeochemical cycling of sulfur group elements in association with microbial roles, and suggests that 210Po may be useful as a tracer of nitrogen fixation in the ocean.

  14. Gravidez na adolescência: um olhar sobre um fenômeno complexo

    Directory of Open Access Journals (Sweden)

    Ana Cristina Garcia Dias

    2010-04-01

    Full Text Available O presente trabalho apresenta uma revisão seletiva e não sistemática da literatura a respeito do fenômeno da gestação na adolescência. Três eixos temáticos orientam a organização do trabalho: (a Riscos e problemas associados à gestação na adolescência; (b Fatores precursores relacionados à gravidez na adolescência; e (c Fatores sócio-culturais associados ao desejo de ser mãe na adolescência. Entre as conclusões, destaca-se que a gravidez na adolescência é uma experiência que pode ter consequências tanto negativas quanto positivas para os adolescentes. Além disso, o fenômeno evidencia a necessidade de intervenções voltadas à saúde sexual e reprodutiva dos adolescentes.

  15. Diprionidae sawflies on lodgepole and ponderosa pines

    Science.gov (United States)

    Eight species of Diprionidae feed on lodgepole pine (Pinus contorta) and ponderosa pine (P. ponderosa) in western United States: Neodiprion burkei Middleton, N. annulus contortae Ross, N. autumnalis Smith, N. fulviceps (Cresson), N. gillettei (Rohwer), N. mundus Rohwer, N. ventralis Ross, and Zadi...

  16. Tracking climate change in oligotrophic mountain lakes: Recent hydrology and productivity synergies in Lago de Sanabria (NW Iberian Peninsula).

    Science.gov (United States)

    Jambrina-Enríquez, Margarita; Recio, Clemente; Vega, José Carlos; Valero-Garcés, Blas

    2017-07-15

    Mountain lakes are particularly sensitive to global change as their oligotrophic conditions may be rapidly altered after reaching an ecological threshold, due to increasing human impact and climate change. Sanabria Lake, the largest mountain lake in the Iberian Peninsula and with a recent history of increased human impact in its watershed, provides an opportunity to investigate recent trends in an oligotrophic, hydrologically-open mountain lake, and their relationship with climate, hydrological variability and human pressure. We conducted the first systematic and detailed survey of stable isotope compositions of Sanabria Lake and Tera River together with limnological analyses during 2009-2011. δ 18 O lakewater and δD lakewater seasonal fluctuations are strongly linked to river discharges, and follow the monthly mean isotopic composition of precipitation, which is controlled by NAO dynamics. δ 13 C POM and δ 13 C DIC revealed higher contribution of allochthonous organic matter in winter and spring due to higher river inflow and lower primary productivity. Increased phytoplankton biomass in late summer correlated significantly with higher pH and Chl-a, and higher nutrient input and lower river inflow. However, the small δ 13 C POM seasonal amplitude underlines the stability of the oligotrophic conditions and the isotopic variation in POM and DIC reflect small seasonal fluctuations mostly as a consequence of strong throughflow. The stability of hydrology and productivity patterns is consistent with Holocene and last millennium reconstructions of past limnological changes in Sanabria Lake. The results of this study indicate that trophic state in this hydrologically-open mountain lake is strongly controlled by climate variability, but recent changes in human-land uses have increased sediment delivery and nutrients supply to the lake and have to be considered for management policies. Monitoring surveys including isotope techniques provide snapshots of modern isotope

  17. Tree response and mountain pine beetle attack preference, reproduction, and emergence timing in mixed whitebark and lodgepole pines

    Science.gov (United States)

    Barbara J. Bentz; Celia Boone; Kenneth F. Raffa

    2015-01-01

    Mountain pine beetle (Dendroctonus ponderosae) is an important disturbance agent in Pinus ecosystems of western North America, historically causing significant tree mortality. Most recorded outbreaks have occurred in mid elevation lodgepole pine (Pinus contorta). In warm years, tree mortality also occurs at higher elevations in mixed species stands.

  18. Fenótipos clínicos de asma grave Clinical phenotypes of severe asthma

    Directory of Open Access Journals (Sweden)

    Roseliane de Souza Araújo Alves

    2008-09-01

    Full Text Available OBJETIVO: Estabelecer os fenótipos clínicos em portadores de asma grave. MÉTODOS: Foram estudados, retrospectivamente, 111 pacientes em um ambulatório especializado. Os pacientes foram avaliados e acompanhados de maneira sistemática, estabelecendo-se ao final do acompanhamento a adesão e o controle ou não da doença por dados clínicos e funcionais. A resistência ao tratamento foi definida como o não preenchimento, ao final do acompanhamento, por pelo menos seis meses, dos critérios de controle de asma, apesar do uso correto e adesão à medicação. Os fenótipos foram determinados por análise fatorial e comparados por testes diversos. RESULTADOS: Ao final, 88 pacientes foram considerados aderentes e 23 não aderentes. Por análise fatorial do grupo aderente, quatro fenótipos foram determinados: o fenótipo 1 (28 pacientes, formado pelos pacientes resistentes ao tratamento, com maior freqüência de sintomas noturnos, maior número de exacerbações e uso mais freqüente de broncodilatador de resgate; o fenótipo 2 (48 pacientes, formado pelos pacientes com obstrução persistente, com menores valores de relação volume expiratório forçado no primeiro segundo/capacidade vital forçada na avaliação inicial, idade mais avançada e maior tempo de doença; o fenótipo 3 (42 pacientes, representa os pacientes com rinossinusite alérgica, sendo constituído de não fumantes com obstrução predominantemente reversível; e o fenótipo 4 (15 pacientes, formado por casos com história de intolerância à aspirina associado à asma quase fatal. CONCLUSÕES: Um número significativo de portadores de ama grave não adere ao tratamento. Muitos pacientes com asma grave têm obstrução irreversível, mas o fenótipo clínico mais relevante é constituído pelos pacientes resistentes ao tratamento habitual.OBJECTIVE: To characterize clinical phenotypes of severe asthma. METHODS: A total of 111 patients were retrospectively evaluated at a

  19. Direct seeding of pitch pine in southern New Jersey

    Science.gov (United States)

    S. Little; C. B. Cranmer; H. A. Somes

    1958-01-01

    There is not enough pine reproduction in the woodlands of southern New Jersey. This increasingly important problem, which plagues the state's Pine Region, is especially severe where seed sources for natural regeneration are poor. In some of these areas, pulpwood cuttings have removed all pines large enough to bear many cones. In other areas, wildfires have killed...

  20. White pines, blister rust, and management in the Southwest

    Science.gov (United States)

    D. A. Conklin; M Fairweather; D Ryerson; B Geils; D Vogler

    2009-01-01

    White pines in New Mexico and Arizona are threatened by the invasive disease white pine blister rust, Cronartium ribicola. Blister rust is already causing severe damage to a large population of southwestern white pine in the Sacramento Mountains of southern New Mexico. Recent detection in northern and western New Mexico suggests that a major expansion of the...

  1. Mineral Analysis of Pine Nuts (Pinus spp.) Grown in New Zealand.

    Science.gov (United States)

    Vanhanen, Leo P; Savage, Geoffrey P

    2013-04-03

    Mineral analysis of seven Pinus species grown in different regions of New Zealand; Armand pine ( Pinus armandii Franch), Swiss stone pine ( Pinus cembra L.), Mexican pinyon ( Pinus cembroides Zucc. var. bicolor Little), Coulter pine ( Pinus coulteri D. Don), Johann's pine ( Pinus johannis M.F. Robert), Italian stone pine ( Pinus pinea L.) and Torrey pine ( Pinus torreyana Parry ex Carrière), was carried out using an inductively coupled plasma optical emission spectrophotometer (ICP-OES) analysis. Fourteen different minerals (Al, B, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, S and Zn) were identified in all seven varieties, except that no Al or Na was found in Pinus coulteri D. Don. New Zealand grown pine nuts are a good source of Cu, Mg, Mn, P and Zn, meeting or exceeding the recommended RDI for these minerals (based on an intake of 50 g nuts/day) while they supplied between 39%-89% of the New Zealand RDI for Fe. Compared to other commonly eaten tree-nuts New Zealand grown pine nuts are an excellent source of essential minerals.

  2. The most oligotrophic subtropical zones of the global ocean: similarities and differences in terms of chlorophyll and yellow substance

    Directory of Open Access Journals (Sweden)

    A. Morel

    2010-10-01

    Full Text Available The cores of the subtropical anticyclonic gyres are characterized by their oligotrophic status and minimal chlorophyll concentration, compared to that of the whole ocean. These zones are unambiguously detected by space borne ocean color sensors thanks to their typical spectral reflectance, which is that of extremely clear and deep blue waters. Not only the low chlorophyll (denoted [Chl] level, but also a reduced amount of colored dissolved organic matter (CDOM or "yellow substance" account for this clarity. The oligotrophic waters of the North and South Pacific gyres, the North and South Atlantic gyres, and the South Indian gyre have been comparatively studied with respect to both [Chl] and CDOM contents, by using 10-year data (1998–2007 of the Sea-viewing Wide field-of-view Sensor (SeaWiFS, NASA. Albeit similar these oligotrophic zones are not identical regarding their [Chl] and CDOM contents, as well as their seasonal cycles. According to the zone, the averaged [Chl] value varies from 0.026 to 0.059 mg m−3, whereas the ay(443 average (the absorption coefficient due to CDOM at 443 nm is between 0.0033 and 0.0072 m−1. The CDOM-to-[Chl] relative proportions also differ between the zones. The clearest waters, corresponding to the lowest [Chl] and CDOM concentrations, are found near Easter Island and near Mariana Islands in the western part of the North Pacific Ocean. In spite of its low [Chl], the Sargasso Sea presents the highest CDOM content amongst the six zones studied. Except in the North Pacific gyre (near Mariana and south of Hawaii islands, a conspicuous seasonality appears to be the rule in the other 4 gyres and affects both [Chl] and CDOM; both quantities vary in a ratio of about 2 (maximum-to-minimum. Coinciding [Chl] and CDOM peaks occur just after the local winter solstice, which is also the period of the maximal mixed layer depth in these latitudes. It is hypothesized that the vertical

  3. Changes in transpiration and foliage growth in lodgepole pine trees following mountain pine beetle attack and mechanical girdling

    Science.gov (United States)

    Robert M. Hubbard; Charles C. Rhoades; Kelly Elder; Jose Negron

    2013-01-01

    The recent mountain pine beetle outbreak in North American lodgepole pine forests demonstrates the importance of insect related disturbances in changing forest structure and ecosystem processes. Phloem feeding by beetles disrupts transport of photosynthate from tree canopies and fungi introduced to the tree's vascular system by the bark beetles inhibit water...

  4. Collins pine/BCI biomass to ethanol project

    International Nuclear Information System (INIS)

    Yancy, M.A.; Hinman, N.D.; Sheehan, J.J.; Tiangco, V.M.

    1999-01-01

    California has abundant biomass resources and a growing transportation fuels market. These two facts have helped to create an opportunity for biomass to ethanol projects within the state. One such project under development is the Collins Pine/BCI Project. Collins Pine Company and BC International (BCI) have teamed up to develop a forest biomass to ethanol facility to be collocated with Collins Pine's 12 MW, biomass-fueled electric generator in Chester, California. The Collins Pine Company (headquartered in Portland, Oregon) is an environmentally progressive lumber company that has owned and operated timberlands near Chester, California since the turn of the century. Collins manages 100,000 acres of timberland in the immediate area of the project. BCI (Dedham, Massachusetts) holds an exclusive license to a new, patented biotechnological process to convert lignocellulosic materials into ethanol and other specially chemicals with significant cost savings and environmental benefits. The project has received a California Energy Commission PIER program award to continue the developmental work done in the Quincy Library Group's Northeastern California Ethanol Manufacturing Feasibility Study (November 1997). This paper provides (1) a brief overview of the biomass and transportation fuels market in California; (2) the current status of the Collins Pine/BCI biomass ethanol project; and (3) future prospects and hurdles for the project to overcome. (author)

  5. First report of the white pine blister rust fungus, Cronartium ribicola, infecting Pinus flexilis on Pine Mountain, Humboldt National Forest, Elko County, northeastern Nevada, U.S.A.

    Science.gov (United States)

    Detlev R. Vogler; Patricia E. Maloney; Tom Burt; Jacob W. Snelling

    2017-01-01

    In 2013, while surveying for five-needle white pine cone crops in northeastern Nevada, we observed white pine blister rust, caused by the rust pathogen Cronartium ribicola Fisch., infecting branches and stems of limber pines (Pinus flexilis James) on Pine Mountain (41.76975°N, 115.61622°W), Humboldt National Forest,...

  6. Cadmium Removal from Aqueous Solutions by Ground Pine Cone

    Directory of Open Access Journals (Sweden)

    H Izanloo, S Nasseri

    2005-01-01

    Full Text Available A study on the removal of cadmium ions from aqueous solutions by pine cone was conducted in batch conditions. Kinetic data and equilibrium removal isotherms were obtained. The influence of different experimental parameters such as contact time, initial concentration of cadmium, pine cone mass and particle size, and temperature on the kinetics of cadmium removal was studied. Results showed that the main parameters that played an important role in removal phenomenon were initial cadmium concentration, particle size and pine cone mass. The necessary time to reach equilibrium was between 4 and 7 hours based on the initial concentration of cadmium. The capacity of cadmium adsorption at equilibrium increased with the decrease of pine cone particle size. The capacity of cadmium adsorption at equilibrium by pine cone increased with the quantity of pine cone introduced (1–4 g/L. Temperature in the range of 20-30°C showed a restricted effect on the removal kinetics (13.56 mg/g at 20°C and a low capacity of adsorption about 11.48 mg/g at 30°C. The process followed pseudo second-order kinetics. The cadmium uptake of pine cone was quantitatively evaluated using adsorption isotherms. Results indicated that the Langmuir model gave a better fit to the experimental data in comparison with the Freundlich equation.

  7. Water Source Utilization of Hammock and Pine Rockland Plant Communities in the Everglades, USA.

    Science.gov (United States)

    Saha, A. K.; Sternberg, L.; Miralles-Wilhelm, F.

    2007-12-01

    South Florida has a mosaic of plant communities resulting from topographical differences, spatially varying hydroperiods and fire. The only plant communities not flooded in the wet season are hardwood hammocks and often pine rocklands. Natural fires burn off litter accumulated in pine rocklands, with the exception of organic matter in sinkholes in the limestone bedrock. This relative lack of soil is thought to constrain pineland plants in the Everglades to depend upon groundwater that is typically low in nutrients. In contrast, adjoining hardwood hammocks have accumulated an organic soil layer that traps rainwater and nutrients. Plants in hammocks may be able to utilize this water and thereby access nutrients present in the litter. Hammocks are thus viewed as localized areas of high nutrients and instances of vegetation feedback upon the oligotrophic everglades landscape enabling establishment and survival of flood-intolerant tropical hardwood species. This study examines water source use and couples it to foliar nutrient concentrations of plants found in hammocks and pinelands. We examined the δ2H and δ18O of stem waters in plants in Everglades National Park and compared those with the δ2H and δ18O of potential water sources. In the wet season hammock plants accessed both groundwater and water in the surface organic soil layer while in the dry season they relied more on groundwater. A similar seasonal shift was observed in pineland plants; however groundwater constituted a much higher proportion of total water uptake throughout the year under observation. Concomitant with differential water utilization by hammock and pineland plant communities, we observed hammock plants having a significantly higher annual mean foliar N and P concentration than pineland plants. Most hammock species are intolerant of flooded soils and are thus constrained by the high water table in the wet season, yet access the lowered groundwater table in the dry season due to drying up of

  8. Natural regeneration of whitebark pine: Factors affecting seedling density

    Science.gov (United States)

    S. Goeking; D. Izlar

    2014-01-01

    Whitebark pine (Pinus albicaulis) is an ecologically important species in high-altitude areas of the western United States and Canada due to the habitat and food source it provides for Clark’s nutcrackers, red squirrels, grizzly bears, and other animals. Whitebark pine stands have recently experienced high mortality due to wildfire, white pine blister rust, and a...

  9. Los fenómenos psicológicos no investigados en la comunicación educativa

    OpenAIRE

    Ortiz-Torres, Emilio Alberto

    2017-01-01

    Propósito: el artículo tiene por objetivo valorar la importancia del estudio científico de los fenómenos psicológicos la sugestión, la percepción interpersonal y el rumor, los cuales inciden en la comunicación educativa. Tema: el tema que se trabaja es la existencia e influencia de dichos fenómenos subjetivos en los diferentes contextos formativos donde se desarrolla la comunicación interpersonal. Desarrollo: se realiza un análisis teórico sobre la comunicación educativa como concepto interdi...

  10. Utilization of the southern pines

    Energy Technology Data Exchange (ETDEWEB)

    Koch, P

    1972-01-01

    After several years out of print, this book is again available. The two-volume reference characterizes the southern pine tree as raw material and describes the process by which it is converted to use. All 10 species are considered. The book is addressed primarily to the incoming generation of researchers and industrial managers in the southern pine industry. Foremen, superintendents, quality control personnel, wood procurement men, forest managers, extension workers, professors, and students of wood technology should find the handbook of value.

  11. Landscape history, calcareous fen development and historical events in the Slovak Eastern Carpathians

    Czech Academy of Sciences Publication Activity Database

    Jamrichová, Eva; Hájková, Petra; Horsák, M.; Rybníčková, E.; Lacina, A.; Hájek, Michal

    2014-01-01

    Roč. 23, č. 5 (2014), s. 497-513 ISSN 0939-6314 Institutional support: RVO:67985939 Keywords : forest development * spring fen * multi-proxy Subject RIV: EF - Botanics Impact factor: 2.648, year: 2014

  12. Soluble and colloidal iron in the oligotrophic North Atlantic and North Pacific.

    Science.gov (United States)

    Wu, J; Boyle, E; Sunda, W; Wen, L S

    2001-08-03

    In the oligotrophic North Atlantic and North Pacific, ultrafiltration studies show that concentrations of soluble iron and soluble iron-binding organic ligands are much lower than previously presumed "dissolved" concentrations, which were operationally defined as that passing through a 0.4-micrometer pore filter. Our studies indicate that substantial portions of the previously presumed "dissolved" iron (and probably also iron-binding ligands) are present in colloidal size range. The soluble iron and iron-binding organic ligands are depleted at the surface and enriched at depth, similar to distributions of major nutrients. By contrast, colloidal iron shows a maximum at the surface and a minimum in the upper nutricline. Our results suggest that "dissolved" iron may be less bioavailable to phytoplankton than previously thought and that iron removal through colloid aggregation and settling should be considered in models of the oceanic iron cycle.

  13. Fen ecohydrologic trajectories in response to groundwater drawdown with edaphic, floristic, and hydrologic feedbacks

    Science.gov (United States)

    Booth, E.; Steven, L. I.; Bart, D.

    2017-12-01

    Calcareous fens are unique and often isolated ecosystems of high conservation value worldwide because they provide habitat for many rare plant and animal species. Their identity is inextricably linked to an absolute dependence on a consistent discharge of groundwater that saturates the near surface for most of the growing season leading to the accumulation of carbon as peat or tufa and sequestration of nutrients. The stresses resulting from consistent saturation and low-nutrient availability result in high native plant diversity including very high rare species richness compared to other ecosystems. Decreases in the saturation stress by reduced groundwater inputs (e.g., from nearby pumping) can result in losses of native diversity, decreases in rare-species abundance, and increased invasion by non-native species. As such, fen ecosystems are particularly susceptible to changes in groundwater conditions including reduction in water levels due to nearby groundwater pumping. Trajectories of degradation are complex due to feedbacks between loss of soil organic carbon, changes in soil properties, and plant water use. We present a model of an archetype fen that couples a hydrological niche model with a variably-saturated groundwater flow model to predict changes in vegetation composition in response to different groundwater drawdown scenarios (step change, declining trend, and periodic drawdown during dry periods). The model also includes feedbacks among vegetation composition, plant water use, and soil properties. The hydrological niche models (using surface soil moisture as predictor) and relationships between vegetation composition, plant water use (via stomatal conductance and leaf-area index), and soil hydraulic properties (van Genuchten parameters) were determined based on data collected from six fens in Wisconsin under various states of degradation. Results reveal a complex response to drawdown and provide insight into other ecosystems with linkages between the

  14. Some recent developments in white-pine weevil research in the Northeast

    Science.gov (United States)

    H. A. Jaynes

    1958-01-01

    Eastern white pine is one of the most important sawtimber species in the Northeast. This species would have still greater potential value were it not for the white-pine weevil, Pissodes strobi (Peck), its most serious insect pest. This is a native insect that occurs throughout the range of eastern white pine. A large percentage of the white pines in...

  15. Effects of dwarf mistletoe on stand structure of lodgepole pine forests 21-28 years post-mountain pine beetle epidemic in central Oregon.

    Directory of Open Access Journals (Sweden)

    Michelle C Agne

    Full Text Available Lodgepole pine (Pinus contorta forests are widely distributed throughout North America and are subject to mountain pine beetle (Dendroctonus ponderosae epidemics, which have caused mortality over millions of hectares of mature trees in recent decades. Mountain pine beetle is known to influence stand structure, and has the ability to impact many forest processes. Dwarf mistletoe (Arceuthobium americanum also influences stand structure and occurs frequently in post-mountain pine beetle epidemic lodgepole pine forests. Few studies have incorporated both disturbances simultaneously although they co-occur frequently on the landscape. The aim of this study is to investigate the stand structure of lodgepole pine forests 21-28 years after a mountain pine beetle epidemic with varying levels of dwarf mistletoe infection in the Deschutes National Forest in central Oregon. We compared stand density, stand basal area, canopy volume, proportion of the stand in dominant/codominant, intermediate, and suppressed cohorts, average height and average diameter of each cohort, across the range of dwarf mistletoe ratings to address differences in stand structure. We found strong evidence of a decrease in canopy volume, suppressed cohort height, and dominant/codominant cohort diameter with increasing stand-level dwarf mistletoe rating. There was strong evidence that as dwarf mistletoe rating increases, proportion of the stand in the dominant/codominant cohort decreases while proportion of the stand in the suppressed cohort increases. Structural differences associated with variable dwarf mistletoe severity create heterogeneity in this forest type and may have a significant influence on stand productivity and the resistance and resilience of these stands to future biotic and abiotic disturbances. Our findings show that it is imperative to incorporate dwarf mistletoe when studying stand productivity and ecosystem recovery processes in lodgepole pine forests because of its

  16. Effects of dwarf mistletoe on stand structure of lodgepole pine forests 21-28 years post-mountain pine beetle epidemic in central Oregon.

    Science.gov (United States)

    Agne, Michelle C; Shaw, David C; Woolley, Travis J; Queijeiro-Bolaños, Mónica E

    2014-01-01

    Lodgepole pine (Pinus contorta) forests are widely distributed throughout North America and are subject to mountain pine beetle (Dendroctonus ponderosae) epidemics, which have caused mortality over millions of hectares of mature trees in recent decades. Mountain pine beetle is known to influence stand structure, and has the ability to impact many forest processes. Dwarf mistletoe (Arceuthobium americanum) also influences stand structure and occurs frequently in post-mountain pine beetle epidemic lodgepole pine forests. Few studies have incorporated both disturbances simultaneously although they co-occur frequently on the landscape. The aim of this study is to investigate the stand structure of lodgepole pine forests 21-28 years after a mountain pine beetle epidemic with varying levels of dwarf mistletoe infection in the Deschutes National Forest in central Oregon. We compared stand density, stand basal area, canopy volume, proportion of the stand in dominant/codominant, intermediate, and suppressed cohorts, average height and average diameter of each cohort, across the range of dwarf mistletoe ratings to address differences in stand structure. We found strong evidence of a decrease in canopy volume, suppressed cohort height, and dominant/codominant cohort diameter with increasing stand-level dwarf mistletoe rating. There was strong evidence that as dwarf mistletoe rating increases, proportion of the stand in the dominant/codominant cohort decreases while proportion of the stand in the suppressed cohort increases. Structural differences associated with variable dwarf mistletoe severity create heterogeneity in this forest type and may have a significant influence on stand productivity and the resistance and resilience of these stands to future biotic and abiotic disturbances. Our findings show that it is imperative to incorporate dwarf mistletoe when studying stand productivity and ecosystem recovery processes in lodgepole pine forests because of its potential to

  17. The effect of habitat fragmentation and abiotic factors on fen plant occurrence

    NARCIS (Netherlands)

    Soomers, H.; Karssenberg, D.J.; Verhoeven, J.T.A.; Verweij, P.A.; Wassen, M.J.

    2013-01-01

    Human landscape modification has led to habitat fragmentation for many species. Habitat fragmentation, leading to isolation, decrease in patch size and increased edge effect, is observed in fen ecosystems that comprise many endangered plant species. However, until now it has remained unclear

  18. Evolution of a research prototype expert system for endemic populations of mountain pine beetle in lodgepole pine forests

    Science.gov (United States)

    Dale L. Bartos; Kent B. Downing

    1989-01-01

    A knowledge acquisition program was written to aid in obtaining knowledge from the experts concerning endemic populations of mountain pine beetle in lodgepole pine forest. An application expert system is then automatically generated by the knowledge acquisition program that contains the codified base of expert knowledge. Data can then be entered into the expert system...

  19. Blue-stain Fungi Associated with Roots of Southern Pine Trees Attacked by the Southern Pine Beetle, Dendroctonus frontalis

    Science.gov (United States)

    William J. Otrosina; Nolan J. Hess; Stanley J. Zarnoch; Thelma J. Perry; John P. Jones

    1997-01-01

    Forty paired plots were established from eastern Texas to Alabama to study root-infecting, blue-stain fungi in southern pine stands undergoing southern pine beetle (SPB) attack. Woody roots were sampled in plots undergoing recent or current attack by the SPB. Comparisons were made between occurrence of Lcptogrqhiumspp. and related fungi and data on various...

  20. Direct and indirect chemical defence of pine against folivorous insects

    NARCIS (Netherlands)

    Mumm, R.; Hilker, M.

    2006-01-01

    The chemical defence of pine against herbivorous insects has been intensively studied with respect to its effects on the performance and behaviour of the herbivores as well as on the natural enemies of pine herbivores. The huge variety of terpenoid pine components play a major role in mediating

  1. The hydrological and geochemical isolation of a freshwater bog within a saline fen in north-eastern Alberta

    Directory of Open Access Journals (Sweden)

    S.J. Scarlett

    2013-10-01

    Full Text Available In the oil sands development region near Fort McMurray, Alberta, wetlands cover ~62 % of the landscape, and ~95 % of these wetlands are peatlands. A saline fen was studied as a reference site for peatland reclamation. Despite highly saline conditions, a freshwater bog was observed in the path of local saline groundwater flow. The purpose of this study was to identify the hydrological controls that have allowed the development and persistence of a bog in this setting. The presence of bog vegetation and its dilute water chemistry suggest that saline groundwater from the fen rarely enters the bog, which functions predominantly as a groundwater recharge system. Chloride (Cl– and sodium (Na+ were the dominant ions in fen water, with concentrations averaging 5394 and 2307 mg L-1, respectively, while the concentrations in bog water were 5 and 4 mg L-1, respectively. These concentrations were reflected by salinity and electrical conductivity measurements, which in the fen averaged 9.3 ppt, and 15.8 mS cm-1, respectively, and in the bog averaged 0.1 ppt and 0.3 mS cm-1, respectively. A small ridge in the mineral substratum was found at the fen–bog margin, which created a persistent groundwater mound. Under the dry conditions experienced in early summer, groundwater flow was directed away from the bog at a rate of 14.6 mm day-1. The convex water table at the fen-bog margin impeded flow of saline water into the bog and instead directed it around the bog margin. However, the groundwater mound was eliminated during flooding in autumn, when the horizontal hydraulic gradient across the margin became negligible, suggesting the possibility of saline water ingress into the bog under these conditions.

  2. 75 FR 29686 - Proposed Establishment of the Pine Mountain-Mayacmas Viticultural Area

    Science.gov (United States)

    2010-05-27

    ... states that local growers report that Pine Mountain vineyards are naturally free of mildew, a vineyard... often stall over Pine Mountain and the Mayacmas range, dropping more rain than in other areas. Pine..., these mountain soils include large amounts of sand and gravel. Pine Mountain soils are generally less...

  3. Fenólicos totais e capacidade antioxidante in vitro de polpas de frutos tropicais

    Directory of Open Access Journals (Sweden)

    Luanne Morais Vieira

    2011-09-01

    Full Text Available O consumo de frutos e suas polpas tem sido muito recomendado por seu valor nutricional, alto teor de fibras, vitamina C e carotenoides. Trabalhos recentes têm apontado esses alimentos como fontes de compostos fenólicos com ação antioxidante, portanto sequestradores de radicais livres, com ação protetora contra o surgimento e/ou desenvolvimento de processos degenerativos que conduzem a doenças crônicas não transmissíveis. Devido à crescente comercialização e consumo de polpas de frutas no Brasil, especialmente na cidade de Teresina-Piauí, este trabalho selecionou um grupo de polpas de frutos de elevado consumo local para avaliação do teor de fenólicos totais e da atividade antioxidante in vitro pelo método de captura de radicais livres: DPPH (radical 1,1-diphenil-2-picrilhydrazil e ABTS (radical 2,2'azinobis(3-ethylbenzthiazoline-6-sulfonic acid. Os frutos selecionados foram: Acerola (Malpighia emarginata DC., Bacuri (Platonia insignis Mart., Cajá (Spondias mombin L., Caju (Anacardium occidentale, Goiaba(Psidium guajava e Tamarindo (Tamarindus indica L.. Os teores de fenólicos totais encontrados nas polpascongeladas destes frutos exibiram quantidades relevantes de polifenóis, destacando-se a polpa de acerola com 835,25 ± 32,44 e 449,63 ± 10,24 mg /100g nos extratos aquosos e hidroalcoólicos, respectivamente, seguido pela polpa de caju com 201,61 ± 19,15 e 165,07 ± 4,10 mg /100g. As polpas de bacuri e tamarindo foram as que apresentaram os menores teores de fenólicos totais. Com relação à atividade antioxidante in vitro, os melhores resultados foram encontrados para os extratos aquosos e hidroalcoólicos das polpas de acerola, caju e goiaba. A capacidade antioxidante destas polpas (EC50 em µg/mL variou de 24,42 a 413,36 e de 1,74 a 259,18 para os extratos aquosos e hidroalcoólicos, respectivamente. Utilizando o radical ABTS, a atividade antioxidante para essas mesmas polpas de frutas apresentou valores TEAC que

  4. Restoring fire in lodgepole pine forests of the Intermountain west

    Science.gov (United States)

    Colin C. Hardy; Ward W. McCaughey

    1997-01-01

    We are developing new management treatments for regenerating and sustaining lodgepole pine (Pinus contorta) forests through emulation of natural disturbance processes. Lodgepole pine is the principal forest cover on over 26 million hectares in western North America. While infrequent, stand replacing fires following mountain pine beetle outbreaks are common to the...

  5. Effects of overstory retention, herbicides, and fertilization on sub-canopy vegetation structure and functional group composition in loblolly pine forests restored to longleaf pine

    Science.gov (United States)

    Benjamin O. Knapp; Joan L. Walker; G. Geoff Wang; Huifeng Hu; Robert N.  Addington

    2014-01-01

    The desirable structure of longleaf pine forests, which generally includes a relatively open canopy of pines, very few woody stems in the mid-story, and a well-developed, herbaceous ground layer, provides critical habitat for flora and fauna and contributes to ecosystem function. Current efforts to restore longleaf pine to upland sites dominated by second-growth...

  6. Diversity of picoeukaryotes at an oligotrophic site off the Northeastern Red Sea Coast.

    Science.gov (United States)

    Acosta, Francisco; Ngugi, David Kamanda; Stingl, Ulrich

    2013-08-20

    Picoeukaryotes are protists ≤ 3 μm composed of a wide diversity of taxonomic groups. They are an important constituent of the ocean's microbiota and perform essential ecological roles in marine nutrient and carbon cycles. Despite their importance, the true extent of their diversity has only recently been uncovered by molecular surveys that resulted in the discovery of a substantial number of previously unknown groups. No study on picoeukaryote diversity has been conducted so far in the main Red Sea basin-a unique marine environment characterized by oligotrophic conditions, high levels of irradiance, high salinity and increased water temperature. We sampled surface waters off the coast of the northeastern Red Sea and analyzed the picoeukaryotic diversity using Sanger-based clone libraries of the 18S rRNA gene in order to produce high quality, nearly full-length sequences. The community captured by our approach was dominated by three main phyla, the alveolates, stramenopiles and chlorophytes; members of Radiolaria, Cercozoa and Haptophyta were also found, albeit in low abundances. Photosynthetic organisms were especially diverse and abundant in the sample, confirming the importance of picophytoplankton for primary production in the basin as well as indicating the existence of numerous ecological micro-niches for this trophic level in the upper euphotic zone. Heterotrophic organisms were mostly composed of the presumably parasitic Marine Alveolates (MALV) and the presumably bacterivorous Marine Stramenopiles (MAST) groups. A small number of sequences that did not cluster closely with known clades were also found, especially in the MALV-II group, some of which could potentially belong to novel clades. This study provides the first snapshot of the picoeukaryotic diversity present in surface waters of the Red Sea, hence setting the stage for large-scale surveying and characterization of the eukaryotic diversity in the entire basin. Our results indicate that the

  7. Microbial communities in dark oligotrophic volcanic ice cave ecosystems of Mt. Erebus, Antarctica

    Directory of Open Access Journals (Sweden)

    Bradley M. Tebo

    2015-03-01

    Full Text Available The Earth’s crust hosts a subsurface, dark, and oligotrophic biosphere that is poorly understood in terms of the energy supporting its biomass production and impact on food webs at the Earth’s surface. Dark oligotrophic volcanic ecosystems (DOVEs are good environments for investigations of life in the absence of sunlight as they are poor in organics, rich in chemical reactants and well known for chemical exchange with Earth’s surface systems. Ice caves near the summit of Mt. Erebus (Antarctica offer DOVEs in a polar alpine environment that is starved in organics and with oxygenated hydrothermal circulation in highly reducing host rock. We surveyed the microbial communities using PCR, cloning, sequencing and analysis of the small subunit (16S ribosomal and Ribulose-1,5-bisphosphate Carboxylase/Oxygenase (RubisCO genes in sediment samples from three different caves, two that are completely dark and one that receives snow-filtered sunlight seasonally. The microbial communities in all three caves are composed primarily of Bacteria and fungi; Archaea were not detected. The bacterial communities from these ice caves display low phylogenetic diversity, but with a remarkable diversity of RubisCO genes including new deeply branching Form I clades, implicating the Calvin-Benson-Bassham cycle as a pathway of CO2 fixation. The microbial communities in one of the dark caves, Warren Cave, which has a remarkably low phylogenetic diversity, were analyzed in more detail to gain a possible perspective on the energetic basis of the microbial ecosystem in the cave. Atmospheric carbon (CO2 and CO, including from volcanic emissions, likely supplies carbon and/or some of the energy requirements of chemoautotrophic microbial communities in Warren Cave and probably other Mt. Erebus ice caves. Our work casts a first glimpse at Mt. Erebus ice caves as natural laboratories for exploring carbon, energy and nutrient sources in the subsurface biosphere and the

  8. Filtering fens: mechanisms explaining phosphorus-limited hotspots of biodiversity in wetlands adjacent to heavily fertilized areas.

    Science.gov (United States)

    Cusell, Casper; Kooijman, Annemieke; Fernandez, Filippo; van Wirdum, Geert; Geurts, Jeroen J M; van Loon, E Emiel; Kalbitz, Karsten; Lamers, Leon P M

    2014-05-15

    The conservation of biodiverse wetland vegetation, including that of rich fens, has a high priority at a global scale. Although P-eutrophication may strongly decrease biodiversity in rich fens, some well-developed habitats do still survive in highly fertilized regions due to nutrient filtering services of large wetlands. The occurrence of such nutrient gradients is well-known, but the biogeochemical mechanisms that determine these patterns are often unclear. We therefore analyzed chemical speciation and binding of relevant nutrients and minerals in surface waters, soils and plants along such gradients in the large Ramsar nature reserve Weerribben-Wieden in the Netherlands. P-availability was lowest in relatively isolated floating rich fens, where plant N:P ratios indicated P-limitation. P-limitation can persist here despite high P-concentrations in surface waters near the peripheral entry locations, because only a small part of the P-input reaches the more isolated waters and fens. This pattern in P-availability appears to be primarily due to precipitation of Fe-phosphates, which mainly occurs close to entry locations as indicated by decreasing concentrations of Fe- and Al-bound P in the sub-aquatic sediments along this gradient. A further decrease of P-availability is caused by biological sequestration, which occurs throughout the wetland as indicated by equal concentrations of organic P in all sub-aquatic sediments. Our results clearly show that the periphery of large wetlands does indeed act as an efficient P-filter, sustaining the necessary P-limitation in more isolated parts. However, this filtering function does harm the ecological quality of the peripheral parts of the reserve. The filtering mechanisms, such as precipitation of Fe-phosphates and biological uptake of P, are crucial for the conservation and restoration of biodiverse rich fens in wetlands that receive eutrophic water from their surroundings. This seems to implicate that biodiverse wetland

  9. Re-measurement of whitebark pine infection and mortality in the Canadian Rockies

    Science.gov (United States)

    Cyndi M. Smith; Brenda Shepherd; Cameron Gillies; Jon Stuart-Smith

    2011-01-01

    Whitebark pine (Pinus albicaulis) populations are under threat across the species' range from white pine blister rust (Cronartium ribicola), mountain pine beetle (Dendroctonus ponderosae), fire exclusion and climate change (Tomback and Achuff 2010). Loss of whitebark pine is predicted to have cascading effects on the following ecological services: provision of...

  10. Survey of foliar monoterpenes across the range of jack pine reveal three widespread chemotypes: implications to host expansion of invasive mountain pine beetle

    Directory of Open Access Journals (Sweden)

    Spencer eTaft

    2015-05-01

    Full Text Available The secondary compounds of pines (Pinus can strongly affect the physiology, ecology and behaviors of the bark beetles (Coleoptera: Curculionidae, Scolytinae that feed on sub-cortical tissues of hosts. Jack pine (Pinus banksiana has a wide natural distribution range in North America (Canada and USA and thus variations in its secondary compounds, particularly monoterpenes, could affect the host expansion of invasive mountain pine beetle (Dendroctonus ponderosae, which has recently expanded its range into the novel jack pine boreal forest. We investigated monoterpene composition of 601 jack pine trees from natural and provenance forest stands representing 63 populations from Alberta to the Atlantic coast. Throughout its range, jack pine exhibited three chemotypes characterized by high proportions of α-pinene, β-pinene, or limonene. The frequency with which the α-pinene and β-pinene chemotypes occurred at individual sites was correlated to climatic variables, such as continentality and mean annual precipitation, as were the individual α-pinene and β-pinene concentrations. However, other monoterpenes were generally not correlated to climatic variables or geographic distribution. Finally, while the enantiomeric ratios of β-pinene and limonene remained constant across jack pine’s distribution, (‒:(+-α-pinene exhibited two separate trends, thereby delineating two α-pinene phenotypes, both of which occurred across jack pine’s range. These significant variations in jack pine monoterpene composition may have cascading effects on the continued eastward spread and success of D. ponderosae in the Canadian boreal forest.

  11. Wollemi Pine: Living Fossil from Jurassic Landscape -RE ...

    Indian Academy of Sciences (India)

    city of Sydney, Australia. This giant ... It is also being exploited to grow commer- cially to ... Australia. There are huge kauri pines (Agathis sps) along with. Wollemi pine seedling ... Natural History Research School of Pacific and Asian Studies.

  12. Variability of rRNA Operon Copy Number and Growth Rate Dynamics of Bacillus Isolated from an Extremely Oligotrophic Aquatic Ecosystem

    Science.gov (United States)

    Valdivia-Anistro, Jorge A.; Eguiarte-Fruns, Luis E.; Delgado-Sapién, Gabriela; Márquez-Zacarías, Pedro; Gasca-Pineda, Jaime; Learned, Jennifer; Elser, James J.; Olmedo-Alvarez, Gabriela; Souza, Valeria

    2016-01-01

    The ribosomal RNA (rrn) operon is a key suite of genes related to the production of protein synthesis machinery and thus to bacterial growth physiology. Experimental evidence has suggested an intrinsic relationship between the number of copies of this operon and environmental resource availability, especially the availability of phosphorus (P), because bacteria that live in oligotrophic ecosystems usually have few rrn operons and a slow growth rate. The Cuatro Ciénegas Basin (CCB) is a complex aquatic ecosystem that contains an unusually high microbial diversity that is able to persist under highly oligotrophic conditions. These environmental conditions impose a variety of strong selective pressures that shape the genome dynamics of their inhabitants. The genus Bacillus is one of the most abundant cultivable bacterial groups in the CCB and usually possesses a relatively large number of rrn operon copies (6–15 copies). The main goal of this study was to analyze the variation in the number of rrn operon copies of Bacillus in the CCB and to assess their growth-related properties as well as their stoichiometric balance (N and P content). We defined 18 phylogenetic groups within the Bacilli clade and documented a range of from six to 14 copies of the rrn operon. The growth dynamic of these Bacilli was heterogeneous and did not show a direct relation to the number of operon copies. Physiologically, our results were not consistent with the Growth Rate Hypothesis, since the copies of the rrn operon were decoupled from growth rate. However, we speculate that the diversity of the growth properties of these Bacilli as well as the low P content of their cells in an ample range of rrn copy number is an adaptive response to oligotrophy of the CCB and could represent an ecological mechanism that allows these taxa to coexist. These findings increase the knowledge of the variability in the number of copies of the rrn operon in the genus Bacillus and give insights about the

  13. Annual changes of bacterial mortality due to viruses and protists in an oligotrophic coastal environment (NW Mediterranean).

    Science.gov (United States)

    Boras, Julia A; Sala, M Montserrat; Vázquez-Domínguez, Evaristo; Weinbauer, Markus G; Vaqué, Dolors

    2009-05-01

    The impact of viruses and protists on bacterioplankton mortality was examined monthly during 2 years (May 2005-April 2007) in an oligotrophic coastal environment (NW Mediterranean Sea). We expected that in such type of system, (i) bacterial losses would be caused mainly by protists, and (ii) lysogeny would be an important type of virus-host interaction. During the study period, viruses and grazers together were responsible for 50.6 +/- 40.1% day(-1) of bacterial standing stock losses (BSS) and 59.7 +/- 44.0% day(-1) of bacterial production losses (BP). Over the first year (May 2005-April 2006), protists were the principal cause of bacterial mortality, removing 29.9 +/- 20.4% day(-1) of BSS and 33.9 +/- 24.3% day(-1) of BP, whereas viral lysis removed 13.5 +/- 17.0% day(-1) of BSS and 12.3 +/- 12.3% day(-1) of BP. During the second year (May 2006-April 2007), viruses caused comparable bacterial losses (29.2 +/- 14.8% day(-1) of BSS and 40.9 +/- 20.7% day(-1) of BP) to protists (28.6 +/- 25.5% day(-1) of BSS and 32.4 +/- 20.0% day(-1) of BP). In 37% of cases higher losses of BP due to viruses than due to protists were found. Lysogenic infection was detected in 11 of 24 samplings. Contrary to our expectations, lytic infections dominated over the two years, and viruses resulted to be a significant source of bacterial mortality in this oligotrophic site.

  14. Native ectomycorrhizal fungi of limber and whitebark pine: Necessary for forest sustainability?

    Science.gov (United States)

    Cathy L. Cripps; Robert K. Antibus

    2011-01-01

    Ectomycorrhizal fungi are an important component of northern coniferous forests, including those of Pinus flexilis (limber pine) and P. albicaulis (whitebark pine) which are being decimated by white pine blister rust and mountain pine beetles. Ectomycorrhizal fungi are known to promote seedling establishment, tree health, and may play a role in forest sustainability....

  15. The influence of vegetation structure on spider species richness, diversity and community organization in the Apšuciems calcareous fen, Latvia

    Energy Technology Data Exchange (ETDEWEB)

    Štokmane, M.; Spuņģis, V.

    2016-07-01

    Calcareous fens are considered to be among the most threatened ecosystems of Europe. They are also one of the most diverse habitats as they support an incredibly rich and diverse range of plant and animal species. However, in spite of their diversity, calcareous fens are still poorly investigated, especially when referring to fen invertebrates, such as spiders. Because spiders are good bioindicators, knowledge of their ecology in rare and threatened habitats is of interest. The aim of this study was to document the composition and diversity of spider species, families and foraging guilds in the ground– and grass–layers of the Apšuciems calcareous fen, and to evaluate the influence of vegetation structure on spider community organization. In summer 2012, we collected ground–dwelling spiders using pitfall traps and grass–dwelling spiders using sweep–netting. A total of 2,937 spider individuals belonging to 19 families and 80 species was collected in the Apšuciems fen. Our results indicate that spider species and families tend to be stratified across the vertical structure of the habitat; the spider composition in the ground stratum differed from that in the grass stratum. On the contrary, however, the spider foraging guild structure between the ground–layer and the grass–layer was similar. Each of the two studied strata presented similar guilds in similar proportions. Our results also showed that spider composition differed considerably between fen parts and that much of this variability could be explained by the architectural properties of the habitat. More diverse vegetation generally supported a higher number of spider species. (Author)

  16. Análisis comparativo de compuestos fenólicos totales y actividad antioxidante de cuatro marcas de tisanas de Hibiscus sabdariffa (Malvaceae comercializadas en Costa Rica

    Directory of Open Access Journals (Sweden)

    Melissa Agüero

    2014-01-01

    Full Text Available Las tisanas de rosa de Jamaica (Hibiscus sabdariffa son consumidas en Costa Rica por su conocido efecto cardioprotector asociado a la presencia de compuestos fenólicos, principalmente antocianinas. Este trabajo estableció diferencias en el perfil de compuestos fenólicos y su actividad anti-radical entre diferentes comercializadores de tisanas de Hibiscus sabdariffa en Costa Rica. Se identificaron cualitativamente taninos, flavonoides y antocianinas. Se cuantificó la cantidad total de compuestos fenólicos por el método de Folin-Ciocalteu y se cuantificó la actividad antioxidante con el método de DPPH. Todas las marcas comerciales demostraron presencia de compuestos fenólicos, incluyendo antocianinas; sin embargo, se encontraron diferencias significativas en el contenido de compuestos fenólicos y actividad anti-radical, entre los diferentes productores de tisanas. Por ello, se concluye que en el mercado costarricense, el perfil en compuestos fenólicos de las tisanas en estudio varía de acuerdo con el productor.

  17. Predicting aquatic macrophyte occurrence in soft-water oligotrophic lakes (Pyrenees mountain range

    Directory of Open Access Journals (Sweden)

    Cristina Pulido

    2014-08-01

    Full Text Available Distribution of aquatic macrophytes in lakes is related to geographical, morphological, catchment and water chemistry variables as well as human impacts, which modify the original environment. Here, we aim at building statistical models to establish the ecological niches of 11 aquatic macrophytes (10 different phanerogams and the genus Nitella from oligotrophic soft-water lakes and infer their ecological requirements and environmental constraints at the southernmost limit of their distribution. Macrophyte occurrence and environmental variables were obtained from 86 non-exploited oligotrophic soft-water lakes from the Pyrenees (Southern Europe; 42º50´N, 1º00´E; macrophytes inhabited 55 of these lakes. Optimum ranges and macrophyte occurrence were predicted in relation to 18 geographical, morphological, catchment and water chemistry variables using univariate and multivariate logistic models. Lakes at low altitude, in vegetated catchments and with low water concentration of NO3- and SO4-2, were the most suitable to host macrophytes. In general, individual species of aquatic macrophytes showed clear patterns of segregation along conductivity and pH gradients, although the specific combination of variables selected in the best models explaining their occurrence differed among species.  Based on the species response to pH and conductivity, we found Isoetes lacustris have its optimum in waters with low conductivity and pH (i.e. negative monotonic response. In contrast, Callitriche palustris, Ranunculus aquatilis, Subularia aquatica, Nitella spp., and Myriophyllum alterniflorum showed an optimum at intermediate values (i.e. unimodal response, whereas Potamogeton berchtoldii, Potamogeton alpinus, and Ranunculus trichophyllus as species had their optimum at relatively high water pH and conductivity (i.e. positive monotonic response. This pattern has been observed in other regions for the same species, although with different optima and tolerance

  18. The most oligotrophic subtropical zones of the global ocean: similarities and differences in terms of chlorophyll and yellow substance

    OpenAIRE

    A. Morel; H. Claustre; B. Gentili

    2010-01-01

    The cores of the subtropical anticyclonic gyres are characterized by their oligotrophic status and minimal chlorophyll concentration, compared to that of the whole ocean. These zones are unambiguously detected by space borne ocean color sensors thanks to their typical spectral reflectance, which is that of extremely clear and deep blue waters. Not only the low chlorophyll (denoted [Chl]) level, but also a reduced amount of colored dissolved organic matter (CDOM or "yellow substance") account ...

  19. The most oligotrophic subtropical zones of the global ocean: similarities and differences in terms of chlorophyll and yellow substance

    OpenAIRE

    Morel, A.; Claustre, H.; Gentili, B.

    2010-01-01

    The cores of the subtropical anticyclonic gyres are characterized by their oligotrophic status and minimal chlorophyll concentration, compared to that of the whole ocean. These zones are unambiguously detected by space borne ocean color sensors thanks to their typical spectral reflectance, which is that of extremely clear and deep blue waters. Not only the low chlorophyll (denoted [Chl]) level, but also a reduced amount of colored dissolved organic matter (CDOM or "yellow substance") acc...

  20. Emission of greenhouse gases from geographically isolated wetlands of Western Siberia

    Science.gov (United States)

    Golovatskaya, E.; Dyukarev, E.; Veretennikova, E.

    2014-12-01

    Wetlands are integral components of landscapes with specific nutrient dynamics and carbon sequestration potentials, which frequently differ, based on hydroperiod and seasonal hydropattern, as well as the constituent concentration of inputs, site-specific storages and vegetation structures. Human modifications have the potential to significantly alter controls on carbon dynamics. This study focused on determining carbon emissions (CO2 and CH4) from geographically isolated peatlands within the Ob-Tom River Interfluve area of Western Siberia affected by water diversion for municipal use by the city of Tomsk, Russia. Two oligotrophic wetlands within the study area were selected for site-specific CO2 studies, the Timiryazevskoe (16 ha) and Kirsanovskoe wetlands (29 ha), both affected by the Tomsk water intake (177 water wells 250 000 m3 water daily). Measurements of СО2 and CH4 emissions from peat surfaces were carried out bi-monthly in growing periods from 2008-2013 in two dominate vegetation zones, pine- shrub-sphagnum phytocenosis (ryam) and sedge-sphagnum fens. СО2 emissions were measured using OPTOGAS-500.4 infrared gas analyzer and dark chamber. Methane emissions were measured using static chamber method. Air samples were collected by syringes and analyzed at gas chromatograph Shimadzu-GC14B. Observations were accompanied by measurement of air temperature and humidity, surface temperature, peat temperature at various depths and the water table level. CО2 emission over the vegetative growing period had clearly pronounced seasonal dynamics with maximum values in the middle of the growing season (mid-July) and minimum values in spring and autumn. The average total flux over the studied period is 123±55 gС/m2 at sedge-sphagnum fen of Kirsanovskoe wetland and 323±66 gС/m2 at fen of Timiryazevskoe wetland. Total СО2 flux for the snow-free period at ryam sites of Timiryazevskoe and Kirsanovskoe wetlands is 238±84 and 260±47 gС/m2 accordingly. Methane

  1. Risk Assessment for the Southern Pine Beetle

    Science.gov (United States)

    Andrew Birt

    2011-01-01

    The southern pine beetle (SPB) causes significant damage (tree mortality) to pine forests. Although this tree mortality has characteristic temporal and spatial patterns, the precise location and timing of damage is to some extent unpredictable. Consequently, although forest managers are able to identify stands that are predisposed to SPB damage, they are unable to...

  2. Experiencias para observar el fenómeno de fluorescencia con luz ultravioleta

    Directory of Open Access Journals (Sweden)

    Heredia Avalos, S.

    2008-09-01

    Full Text Available La fluorescencia tiene lugar cuando una sustancia emite luz visible al absorber radiación de una longitud de onda menor, como por ejemplo luz ultravioleta. La diferencia entre la energía absorbida (del fotón ultravioleta y la emitida (del fotón visible se disipa en forma de calor. Se dice que la sustancia posee fluorescenciacuando este proceso es muy rápido; si es más lento se dice que la sustancia posee fosforescencia. A continuación se describen varias experiencias sencillas para poner de manifiesto el fenómeno de fluorescencia. Todas ellas requieren de reactivos y materiales fácilmente accesibles y asequibles y se pueden realizar con alumnos de secundaria o de bachillerato para poner de manifiesto este fenómeno. Además, también se propone una experiencia en la que se observa la reversibilidad de las reacciones químicas ácido-base a través de la fluorescencia.

  3. Historic forests and endemic mountain pine beetle and dwarf mistletoe

    Science.gov (United States)

    Jose Negron

    2012-01-01

    Mountain pine beetle has always been a significant disturbance agent in ponderosa and lodgepole pine forests in Colorado. Most studies have examined the impacts to forest structure associated with epidemic populations of a single disturbance agent. In this paper we address the role of endemic populations of mountain pine and their interactions with dwarf mistletoe...

  4. Fenómenos de transporte : un curso introductorio

    OpenAIRE

    Betancourt Grajales, Ramiro

    1991-01-01

    Fenómenos de transporte, es el nombre colectivo que se da al estudio sistemático e integrado de tres áreas clásicas de la ciencia de la Ingeniería : 1) Transporte de Energía o Calor, 2) Transporte de Masa o Difusión, y 3) Transporte de Cantidad de Movimiento o Impulso (Momentum en Inglés), o Dinámica de Fluidos. Debido a que con frecuencia el transporte de masa y de calor ocurren en un fluido, algunos planes de estudio incluyen estos procesos en su tratamiento de la mecánica de fluidos....

  5. A cryptic targeting signal creates a mitochondrial FEN1 isoform with tailed R-Loop binding properties.

    Directory of Open Access Journals (Sweden)

    Lawrence Kazak

    Full Text Available A growing number of DNA transacting proteins is found in the nucleus and in mitochondria, including the DNA repair and replication protein Flap endonuclease 1, FEN1. Here we show a truncated FEN1 isoform is generated by alternative translation initiation, exposing a mitochondrial targeting signal. The shortened form of FEN1, which we term FENMIT, localizes to mitochondria, based on import into isolated organelles, immunocytochemistry and subcellular fractionation. In vitro FENMIT binds to flap structures containing a 5' RNA flap, and prefers such substrates to single-stranded RNA. FENMIT can also bind to R-loops, and to a lesser extent to D-loops. Exposing human cells to ethidium bromide results in the generation of RNA/DNA hybrids near the origin of mitochondrial DNA replication. FENMIT is recruited to the DNA under these conditions, and is released by RNase treatment. Moreover, high levels of recombinant FENMIT expression inhibit mtDNA replication, following ethidium bromide treatment. These findings suggest FENMIT interacts with RNA/DNA hybrids in mitochondrial DNA, such as those found at the origin of replication.

  6. Vegetation ecology of eastern white pine and red pine forests in Ontario. Forest fragmentation and biodiversity project technical report No. 11

    Energy Technology Data Exchange (ETDEWEB)

    Carleton, T.J.

    1993-12-31

    This study explored changes in understory species composition and floristic diversity in eastern white pine and red pine stands in Ontario in relation to differences in site condition and stand age. It surveyed 170 natural, fire-origin stands containing at least a 10% component of red pine and white pine basal area throughout the Canadian Shield in Ontario during 1991 and 1992. The stands had not been previously logged and ranged in age from 50-300 years. Sampling was conducted using plots of fixed area. Within these plots, subplots were sampled to capture the variety of vegetation that occurred at different scales. Stand-level data were also recorded outside the fixed area plots. Detailed site data were also collected, including information on soils, topography, coarse woody debris (both standing and fallen), and the nature of the forest floor substrates.

  7. Avian response to pine restoration at Peck Ranch Conservation Area

    Science.gov (United States)

    Richard Clawson; Carrie Steen; Kim Houf; Terry Thompson

    2007-01-01

    Midco Pine Flats is a 2,223-acre region of Peck Ranch Conservation Area (CA) that is classified as a pine-oak plains land type association. Extensive logging in the early 1900s removed most overstory shortleaf pine allowing oak to become the primary overstory component. In 2000, Missouri Department of Conservation staff initiated a pineoak woodland restoration project...

  8. Blister rust control in the management of western white pine

    Science.gov (United States)

    Kenneth P. Davis; Virgil D. Moss

    1940-01-01

    The forest industry of the western white pine region depends on the production of white pine as a major species on about 2,670,000 acres of commercial forest land. Continued production of this species and maintenance of the forest industry at anything approaching its present level is impossible unless the white pine blister rust is controlled. Existing merchantable...

  9. Taxonomy, phylogeny, and coevolution of pines and their stem rusts

    Science.gov (United States)

    C. I. Millar; B. B. Kinloch

    1991-01-01

    We review and reinterpret major events in the evolution of pines and their stem rusts using information from their taxonomy, genetics, biogeography, and fossil history. Understanding of pine evolution has been significantly revised in the last 20 years. Pines appear to have evolved early in the Mesozoic and to have diversified and migrated throughout middle latitudes...

  10. Insects in IBL-4 pine weevil traps

    Science.gov (United States)

    I. Skrzecz

    2003-01-01

    Pipe traps (IBL-4) are used in Polish coniferous plantations to monitor and control the pine weevil (Hylobius abietis L.). This study was conducted in a one-year old pine plantation established on a reforested clear-cut area in order to evaluate the impact of these traps on non-target insects. Evaluation of the catches indicated that species of

  11. Grading sugar pine saw logs in trees.

    Science.gov (United States)

    John W. Henley

    1972-01-01

    Small limbs and small overgrown limbs cause problems when grading saw logs in sugar pine trees. Surface characteristics and lumber recovery information for 426 logs from 64 sugar pine trees were examined. Resulting modifications in the grading specification that allow a grader to ignore small limbs and small limb indicators do not appear to decrease the performance of...

  12. Loblolly pine grown under elevated CO2 affects early instar pine sawfly performance.

    Science.gov (United States)

    Williams, R S; Lincoln, D E; Thomas, R B

    1994-06-01

    Seedlings of loblolly pine Pinus taeda (L.), were grown in open-topped field chambers under three CO 2 regimes: ambient, 150 μl l -1 CO 2 above ambient, and 300 μl l -1 CO 2 above ambient. A fourth, non-chambered ambient treatment was included to assess chamber effects. Needles were used in 96 h feeding trials to determine the performance of young, second instar larvae of loblolly pine's principal leaf herbivore, red-headed pine sawfly, Neodiprion lecontei (Fitch). The relative consumption rate of larvae significantly increased on plants grown under elevated CO 2 , and needles grown in the highest CO 2 regime were consumed 21% more rapidly than needles grown in ambient CO 2 . Both the significant decline in leaf nitrogen content and the substantial increase in leaf starch content contributed to a significant increase in the starch:nitrogen ratio in plants grown in elevated CO 2 . Insect consumption rate was negatively related to leaf nitrogen content and positively related to the starch:nitrogen ratio. Of the four volatile leaf monoterpenes measured, only β-pinene exhibited a significant CO 2 effect and declined in plants grown in elevated CO 2 . Although consumption changed, the relative growth rates of larvae were not different among CO 2 treatments. Despite lower nitrogen consumption rates by larvae feeding on the plants grown in elevated CO 2 , nitrogen accumulation rates were the same for all treatments due to a significant increase in nitrogen utilization efficiency. The ability of this insect to respond at an early, potentially susceptible larval stage to poorer food quality and declining levels of a leaf monoterpene suggest that changes in needle quality within pines in future elevated-CO 2 atmospheres may not especially affect young insects and that tree-feeding sawflies may respond in a manner similar to herb-feeding lepidopterans.

  13. Population dynamics of bacteria associated with different strains of the pine wood nematode Bursaphelenchus xylophilus after inoculation in maritime pine (Pinus pinaster).

    Science.gov (United States)

    Roriz, Mariana; Santos, Carla; Vasconcelos, Marta W

    2011-08-01

    For a long time it was thought that Bursaphelenchus xylophilus was the only agent of the pine wilt disease. Recently, it was discovered that there are bacteria associated with the nematodes that contribute to the pathogenesis of this disease, mainly through the release of toxins that promote the death of the pines. Among the species most commonly found, are bacteria belonging to the Bacillus, Pantoea, Pseudomonas and Xanthomonas genera. The main objective of this work was to study the effect of inoculation of maritime pine (Pinus pinaster) with four different nematode isolates, in the bacterial population of nematodes and trees, at different stages of disease progression. The monitoring of progression of disease symptoms was also recorded. Also, the identification of bacteria isolated from the xylem of trees and the surface of nematodes was performed by classical identification methods, by the API20E identification system and by sequencing of bacterial DNA. The results showed that for the symptoms progression, the most striking difference was observed for the pines inoculated with the avirulent isolate, C14-5, which led to a slower and less severe aggravation of symptoms than in pines inoculated with the virulent isolates. In general, it was found that bacterial population, inside the tree, increased with disease progression. A superior bacterial quantity was isolated from pines inoculated with the nematode isolates HF and 20, and, comparatively, few bacteria were isolated from pines inoculated with the avirulent isolate. The identification system API20E was insufficient in the identification of bacterial species; Enterobacter cloacae species was identified in 79% of the isolated bacterial colonies and seven of these colonies could not be identified by this method. Molecular identification methods, through bacterial DNA sequencing, allowed a more reliable identification: eleven different bacterial species within the Bacillus, Citrobacter, Enterobacter, Escherichia

  14. FT-ICR MS analysis of blended pine-microalgae feedstock HTL biocrudes

    Energy Technology Data Exchange (ETDEWEB)

    Jarvis, Jacqueline M.; Billing, Justin M.; Corilo, Yuri E.; Schmidt, Andrew J.; Hallen, Richard T.; Schaub, Tanner M.

    2018-03-01

    Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) is utilized for direct comparison of the chemical composition of biocrudes generated from the hydrothermal liquefaction of 100% pine, 100% algae, 75:25 pine:algae, and 50:50 pine:algae feedstocks. This analysis reveals that the of the 72:25 and 50:50 pine:algal HTL biocrudes is essentially a composite of the two parent feeds (i.e., pine and algae) with a lower relative abundance of Ox species and a higher relative abundance of nitrogen-containing species than the pine HTL biocrude. Alternatively, the biocrude blends have a lower relative abundance of nitrogen-containing species where N>2 than the algal HTL biocrude. The 75:25 pine:algal HTL biocrude has more elemental formulae in common with the pine HTL biocrude than the 50:50 blend; however, both blends have more elemental formulae in common with the algal HTL biocrude. Interestingly, >20% of the elemental formulae assigned to monoisotopic peaks within the 75:25 and 50:50 biocrude blends are species not present in either the pine or algal HTL biocrudes. The highest relative abundance of these new species belong to the N2O4-6 classes, which correspond to heteroatom classes with a moderate number of nitrogen atoms and higher number of oxygen atoms per molecules than the species within the pure algal HTL biocrude. Compositionally, the novel species have the same structural motif but are of higher DBE and carbon numbers than the species within the algal HTL biocrude. These original species are most likely generated from reactions between molecules from both feeds, which results in compounds wotj higher oxygen content than typically seen in the algal HTL biocrude but also higher nitrogen contents than observed in the pine HTL biocrude.

  15. Post-harvest seedling recruitment following mountain pine beetle infestation of Colorado lodgepole pine stands: A comparison using historic survey records

    Science.gov (United States)

    Byron J. Collins; Charles C. Rhoades; Jeffrey Underhill; Robert M. Hubbard

    2010-01-01

    The extent and severity of overstory lodgepole pine (Pinus contorta var. latifolia Engelm. ex Wats.) mortality from mountain pine beetle (Dendroctonus ponderosae Hopkins) has created management concerns associated with forest regeneration, wildfire risk, human safety, and scenic, wildlife, and watershed resources in western North America. Owing to the unprecedented...

  16. Compostos fenólicos totais, atividade antioxidante e antifúngica demultimisturas enriquecidas com a microalga Spirulina platensis

    OpenAIRE

    Bierhals, Vânia da Silva; Machado, Vanessa Goulart; Echevenguá, Walesca Oliveira; Costa, Jorge Alberto Vieira; Furlong, Eliana Badiale

    2009-01-01

    Com o objetivo de avaliar o conteúdo fenólico e as atividades antioxidantes e antifúngicas de multimisturas enriquecidas com Spirulina platensis, foram formuladas quatro multimisturas com farelo de arroz ou trigo, duas contendo Spirulina platensis e duas com sementes de girassol. Os compostos fenólicos foram estimados pela técnica de Folin-Ciocalteau. A atividade antioxidante foi avaliada por meio de inibição do radical livre DPPH e a atividade antifúngica foi analisada por meio de ensaio de ...

  17. Content of chemical elements in tree rings of lodgepole pine and whitebark pine from a subalpine Sierra Nevada forest

    Science.gov (United States)

    David L. Peterson; Darren R. Anderson

    1990-01-01

    The wood of lodgepole pines and whitebark pines from a high elevation site in the east central Sierra Nevada of California was analyzed for chemical content to determine whether there were any temporal patterns of chemical distribution in tree rings. Cores were taken from 10 trees of each species and divided into 5-year increments for chemical analysis. Correlation...

  18. Key to utilization of hardwoods on pine sites: the shaping-lathe headrig

    Science.gov (United States)

    P. Koch

    1976-01-01

    In past years, only 30% of southern pine biomass (above- and below-ground parts) ended as primary product. Moreover, hardwoods on pine sites were, and in many cases still are, destroyed with no thought of utilization. Now, however, processes have been invented that can raise utilization of each tree- pine and hardwood on pine sites a like to 67% of total biomass,...

  19. Latent resilience in ponderosa pine forest: effects of resumed frequent fire.

    Science.gov (United States)

    Larson, Andrew J; Belote, R Travis; Cansler, C Alina; Parks, Sean A; Dietz, Matthew S

    2013-09-01

    Ecological systems often exhibit resilient states that are maintained through negative feedbacks. In ponderosa pine forests, fire historically represented the negative feedback mechanism that maintained ecosystem resilience; fire exclusion reduced that resilience, predisposing the transition to an alternative ecosystem state upon reintroduction of fire. We evaluated the effects of reintroduced frequent wildfire in unlogged, fire-excluded, ponderosa pine forest in the Bob Marshall Wilderness, Montana, USA. Initial reintroduction of fire in 2003 reduced tree density and consumed surface fuels, but also stimulated establishment of a dense cohort of lodgepole pine, maintaining a trajectory toward an alternative state. Resumption of a frequent fire regime by a second fire in 2011 restored a low-density forest dominated by large-diameter ponderosa pine by eliminating many regenerating lodgepole pines and by continuing to remove surface fuels and small-diameter lodgepole pine and Douglas-fir that established during the fire suppression era. Our data demonstrate that some unlogged, fire-excluded, ponderosa pine forests possess latent resilience to reintroduced fire. A passive model of simply allowing lightning-ignited fires to burn appears to be a viable approach to restoration of such forests.

  20. Accumulation of cesium-137 and strontium-90 in ponderosa pine and monterey pine seedlings

    International Nuclear Information System (INIS)

    Entry, J.A.; Rygiewicz, P.T.; Emmingham, W.H.

    1993-01-01

    Because ponderosa pine Pinus ponderosa and Monterey pone (P. radiata D Don) have exceptionally fast growth rates and their abscised needles are not readily dispersed by wind, these species may be valuable for removing radioisotopes from contaminated soils. Ponderosa and Monterey pine seedlings were tested for their ability to accumulate 137 Cs and 90 Sr-characteristic radioisotopes of nuclear fallout-from contaminated soil. Seedlings were grown for 3 mo in 165 cm 3 sphagnum peat moss/perlite (1:1 V/V) in a growth chamber. In Exp. 1, seedling accumulation of 137 Cs and 90 Sr after 1 mo of exposure was measured. In Exp. 2, seedling accumulation of the radioisotopes during different-length exposures was measured. Seedling accumulation of 137 CS and 90 Sr at different concentrations of the radioisotopes in the growth medium was measured in Exp. 3. Ponderosa pine accumulated 6.3% of the 137 Cs and I.5% of the 90 Sr present in the growth medium after 1 mo; Monterey pine accumulated 8.3% of the 137 Cs and 4.5% of the 90 Sr. Accumulation of 137 Cs and 90 Sr by both coniferous species was curvilinearly related to duration of exposure. Accumulation of 137 Cs and 90 Sr by both species increased with increasing concentration in the growth medium and correlated curvilinearly with radioisotope concentration in the growth medium. Large areas throughout the world are contaminated with 137 Cs and 90 Sr as a result of nuclear weapons testing or atomic reactor accidents. The ability of trees to sequester and store 137 Cs and 90 Sr introduces the possibility of using reforestation to remediate contaminated soils

  1. The influence of vegetation structure on spider species richness, diversity and community organization in the Apšuciems calcareous fen, Latvia

    Directory of Open Access Journals (Sweden)

    Štokmane, M.

    2016-07-01

    Full Text Available Calcareous fens are considered to be among the most threatened ecosystems of Europe. They are also one of the most diverse habitats as they support an incredibly rich and diverse range of plant and animal species. However, in spite of their diversity, calcareous fens are still poorly investigated, especially when referring to fen invertebrates, such as spiders. Because spiders are good bioindicators, knowledge of their ecology in rare and threatened habitats is of interest. The aim of this study was to document the composition and diversity of spider species, families and foraging guilds in the ground– and grass–layers of the Apšuciems calcareous fen, and to evaluate the influence of vegetation structure on spider community organization. In summer 2012, we collected ground–dwelling spiders using pitfall traps and grass–dwelling spiders using sweep–netting. A total of 2,937 spider individuals belonging to 19 families and 80 species was collected in the Apšuciems fen. Our results indicate that spider species and families tend to be stratified across the vertical structure of the habitat; the spider composition in the ground stratum differed from that in the grass stratum. On the contrary, however, the spider foraging guild structure between the ground–layer and the grass–layer was similar. Each of the two studied strata presented similar guilds in similar proportions. Our results also showed that spider composition differed considerably between fen parts and that much of this variability could be explained by the architectural properties of the habitat. More diverse vegetation generally supported a higher number of spider species.

  2. Dynamics of whlte pine in New England

    Science.gov (United States)

    William B. Leak; J.B. Cullen; Thomas S. Frieswyk

    1995-01-01

    Analysis of growth, regeneration, and quality changes for white pine between the 1970's and 1980's in the six-state New England region. Growth rates seemed comparable among ail states except Rhode Island, where the percentage of growth (1.71%) seemed low. Over all states, the proportion of acreage in seedling/sapling white pine stands averaged too low (8%) to...

  3. Response of benthic opportunistic polychaetes and amphipods index to different perturbations in coastal oligotrophic areas (Canary archipelago, North East Atlantic Ocean)

    OpenAIRE

    Riera, Rodrigo; de-la-Ossa-Carretero, Jose Antonio

    2014-01-01

    Oligotrophic areas harbour low macrofaunal abundance and patchy distribution. In these areas it is necessary to test the reliability of biological indicators, especially those based on taxonomic sufficiency where the level of identification is balanced against the need for ecological information and could affect the efficiency of bioindicators. The BOPA (benthic opportunistic polychaetes and amphipods) index was applied in five coastal areas subjected to different perturbations (aquaculture, ...

  4. Short-Term Summer Inundation as a Measure to Counteract Acidification in Rich Fens

    NARCIS (Netherlands)

    Mettrop, I.S.; Cusell, C.; Kooijman, A.M.; Lamers, L.P.M.

    2015-01-01

    In regions with intensive agriculture, water level fluctuation in wetlands has generally become constricted within narrow limits. Water authorities are, however, considering the re-establishment of fluctuating water levels as a management tool in biodiverse, base-rich fens (‘rich fens’). This

  5. Soil contamination with silver nanoparticles reduces Bishop pine growth and ectomycorrhizal diversity on pine roots

    Energy Technology Data Exchange (ETDEWEB)

    Sweet, M. J., E-mail: m.sweet@derby.ac.uk [University of Derby, Environmental Sustainability Research Centre, College of Life and Natural Sciences (United Kingdom); Singleton, I. [Newcastle University, School of Biology (United Kingdom)

    2015-11-15

    Soil contamination by silver nanoparticles (AgNP) is of potential environmental concern but little work has been carried out on the effect of such contamination on ectomycorrhizal fungi (EMF). EMF are essential to forest ecosystem functions as they are known to enhance growth of trees by nutrient transfer. In this study, soil was experimentally contaminated with AgNP (0, 350 and 790 mg Ag/kg) and planted with Bishop pine seedlings. The effect of AgNP was subsequently measured, assessing variation in pine growth and ectomycorrhizal diversity associated with the root system. After only 1 month, the highest AgNP level had significantly reduced the root length of pine seedlings, which in turn had a small effect on above ground plant biomass. However, after 4 months growth, both AgNP levels utilised had significantly reduced both pine root and shoot biomass. For example, even the lower levels of AgNP (350 mg Ag/kg) soil, reduced fresh root biomass by approximately 57 %. The root systems of the plants grown in AgNP-contaminated soils lacked the lateral and fine root development seen in the control plants (no AgNP). Although, only five different genera of EMF were found on roots of the control plants, only one genus Laccaria was found on roots of plants grown in soil containing 350 mg AgNP/kg. At the higher levels of AgNP contamination, no EMF were observed. Furthermore, extractable silver was found in soils containing AgNP, indicating potential dissolution of silver ions (Ag+) from the solid AgNP.

  6. Soil contamination with silver nanoparticles reduces Bishop pine growth and ectomycorrhizal diversity on pine roots

    International Nuclear Information System (INIS)

    Sweet, M. J.; Singleton, I.

    2015-01-01

    Soil contamination by silver nanoparticles (AgNP) is of potential environmental concern but little work has been carried out on the effect of such contamination on ectomycorrhizal fungi (EMF). EMF are essential to forest ecosystem functions as they are known to enhance growth of trees by nutrient transfer. In this study, soil was experimentally contaminated with AgNP (0, 350 and 790 mg Ag/kg) and planted with Bishop pine seedlings. The effect of AgNP was subsequently measured, assessing variation in pine growth and ectomycorrhizal diversity associated with the root system. After only 1 month, the highest AgNP level had significantly reduced the root length of pine seedlings, which in turn had a small effect on above ground plant biomass. However, after 4 months growth, both AgNP levels utilised had significantly reduced both pine root and shoot biomass. For example, even the lower levels of AgNP (350 mg Ag/kg) soil, reduced fresh root biomass by approximately 57 %. The root systems of the plants grown in AgNP-contaminated soils lacked the lateral and fine root development seen in the control plants (no AgNP). Although, only five different genera of EMF were found on roots of the control plants, only one genus Laccaria was found on roots of plants grown in soil containing 350 mg AgNP/kg. At the higher levels of AgNP contamination, no EMF were observed. Furthermore, extractable silver was found in soils containing AgNP, indicating potential dissolution of silver ions (Ag+) from the solid AgNP

  7. Interaction of an invasive bark beetle with a native forest pathogen: Potential effect of dwarf mistletoe on range expansion of mountain pine beetle in jack pine forests

    Science.gov (United States)

    Jennifer Klutsch; Nadir Erbilgin

    2012-01-01

    In recent decades, climate change has facilitated shifts in species ranges that have the potential to significantly affect ecosystem dynamics and resilience. Mountain pine beetle (Dendroctonus ponderosae) is expanding east from British Columbia, where it has killed millions of pine trees, primarily lodgepole pine (Pinus contorta...

  8. A conceptual model for the blooming behavior and persistence of the benthic mat-forming diatom Didymosphenia geminata in oligotrophic streams

    Science.gov (United States)

    Cullis, James D. S.; Gillis, Carole-Anne; Bothwell, Max L.; Kilroy, Cathy; Packman, Aaron; Hassan, Marwan

    2012-06-01

    The benthic, mat-forming diatomDidymosphenia geminata has the unique ability to produce large amounts of algal biomass under oligotrophic conditions in cold, fast flowing streams and rivers. This presents an ecological paradox that challenges our current understanding of stream ecosystem dynamics. Our understanding of the drivers of D. geminata ecology is still limited. Here we present a conceptual model for the blooming behavior and persistence of this species to advance scientific understanding of strategies for life in fast flowing oligotrophic waters and support the design of future research and mitigation measures for nuisance algal blooms. The conceptual model is based on a synthesis of data and ideas from a range of disciplines including hydrology, geomorphology, biogeochemistry, and ecology. The conceptual model highlights the role of water chemistry, river morphology, and flow thresholds in defining the habitat window for D. geminata. We propose that bed disturbance is a primary control on accumulation and persistence of D. geminataand that the removal threshold can be determined by synthesizing site-specific information on hydrology and geomorphology. Further, we propose that a key to understanding the didymo paradox is the separation of cellular reproduction and mat morphology with specific controls acting in respect of the different processes.

  9. Diverging Drought Resistance of Scots Pine Provenances Revealed by Infrared Thermography

    Directory of Open Access Journals (Sweden)

    Hannes Seidel

    2016-08-01

    Full Text Available With recent climate changes, Scots pine (Pinus sylvestris L. forests have been affected by die-off events. Assisted migration of adapted provenances mitigates drought impacts and promotes forest regeneration. Although suitable provenances are difficult to identify by traditional ecophysiological techniques, which are time consuming and invasive, plant water status can be easily assessed by infrared thermography. Thus, we examined the stress responses of 2-year-old potted Scots pine seedlings from six provenances (Bulgaria, France, Germany, Italy, Poland, and Spain based on two thermal indices (crop water stress index and stomatal conductance index. Both indices were derived from infrared images during a six-week drought/control treatment in a greenhouse in the summer of 2013. The pines were monitored during the stress and subsequent recovery period. After controlling for fluctuating environmental conditions, soil moisture or treatment-specific water supply was the most important driver of drought stress. The stress magnitude and response to soil water deficit depended on provenance. Under moderate drought conditions, pines from western and eastern Mediterranean provenances (Bulgaria, France, and Spain expressed lower stress levels than those from both continental provenances (Germany and Poland. In pines from the Spanish and Bulgarian provenances, the stress level differences were significantly lower than in continental pines. Moreover, pines from continental provenances were less resilient (showed less recovery after the stress period than Mediterranean pines. Under extreme drought, all provenances were equally stressed with almost no significant differences in their thermal indices. Provenance-specific differences in drought resistance, which are associated with factors such as summer precipitation at the origin of Scots pine seedlings, may offer promising tracks of adaptation to future drought risks.

  10. Annual cycle of methane emission from a boreal fen measured by the eddy covariance technique

    International Nuclear Information System (INIS)

    Rinne, Janne.; Pihlatie, Mari; Haapanala, Sami; Vesala, Timo; Riutta, Terhi; Tuittila, Eeva-Stiina; Aurela, Mika; Tuovinen, Juha-Pekka

    2007-01-01

    The northern wetlands are one of the major sources of methane into the atmosphere. We measured annual methane emission from a boreal minerotrophic fen, Siikaneva, by the eddy covariance method. The average wintertime emissions were below 1 mg/m 2 /h, and the summertime emissions about 3.5 mg/m 2 /h. The water table depth did have any clear effect on methane emissions. During most of the year the emission depended on the temperature of peat below the water table. However, during the high and late summer the emission was independent on peat temperature as well. No diurnal cycle of methane flux was found. The total annual emission from the Siikaneva site was 12.6 g/m 2 . The emissions of the snow free period contributed 91% to the annual emission. The emission pulse during the snow melting period was clearly detectable but of minor importance adding only less than 3% to the annual emission. Over 20% of the carbon assimilated during the year as carbon dioxide was emitted as methane. Thus methane emission is an important component of the carbon balance of the Siikaneva fen. This indicates need of taking methane into account when studying carbon balances of northern fen ecosystems

  11. Contrasting species-environment relationships in communities of testate amoebae, bryophytes and vascular plants along the fen-bog gradient.

    Science.gov (United States)

    Lamentowicz, Mariusz; Lamentowicz, Lukasz; van der Knaap, Willem O; Gabka, Maciej; Mitchell, Edward A D

    2010-04-01

    We studied the vegetation, testate amoebae and abiotic variables (depth of the water table, pH, electrical conductivity, Ca and Mg concentrations of water extracted from mosses) along the bog to extremely rich fen gradient in sub-alpine peatlands of the Upper Engadine (Swiss Alps). Testate amoeba diversity was correlated to that of mosses but not of vascular plants. Diversity peaked in rich fen for testate amoebae and in extremely rich fen for mosses, while for testate amoebae and mosses it was lowest in bog but for vascular plants in extremely rich fen. Multiple factor and redundancy analyses (RDA) revealed a stronger correlation of testate amoebae than of vegetation to water table and hydrochemical variables and relatively strong correlation between testate amoeba and moss community data. In RDA, hydrochemical variables explained a higher proportion of the testate amoeba and moss data than water table depth. Abiotic variables explained a higher percentage of the species data for testate amoebae (30.3% or 19.5% for binary data) than for mosses (13.4%) and vascular plants (10%). These results show that (1) vascular plant, moss and testate amoeba communities respond differently to ecological gradients in peatlands and (2) testate amoebae are more strongly related than vascular plants to the abiotic factors at the mire surface. These differences are related to vertical trophic gradients and associated niche differentiation.

  12. Rooting Rose Cuttings in Whole Pine Tree Substrates

    Science.gov (United States)

    Increased demand for alternatives to pine bark (PB) and peat moss (P) has led to extensive research on wood-based substrates, such as processed whole pine trees (WPT), for nursery and greenhouse crop production. Limited information is available on how WPT may perform as a rooting substrate for cutti...

  13. Impact of a Mountain Pine Beetle Outbreak on Young Lodgepole Pine Stands in Central British Columbia

    Directory of Open Access Journals (Sweden)

    Amalesh Dhar

    2015-09-01

    Full Text Available The current mountain pine beetle (MPB (Dendroctonous ponderosae Hopkins epidemic has severely affected pine forests of Western Canada and killed millions of hectares of lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm. forest. Generally, MPB attack larger and older (diameter > 20 cm or >60 years of age trees, but the current epidemic extends this limit with attacks on even younger and smaller trees. The study’s aim was to investigate the extent of MPB attack in young pine stands and its possible impact on stand dynamics. Although MPB attacks were observed in trees as small as 7.5 cm diameter at breast height (DBH and as young as 13 years old, the degree of MPB attack (percent stems ha−1 increased with increasing tree diameter and age class (13–20, 21–40, 41–60, and 61–80 years old (6.4%, 49.4%, 62.6%, and 69.5% attack, respectively, by age class which is greater than that reported from previous epidemics for stands of this age. The mean density of surviving residual structure varied widely among age classes and ecological subzones. Depending on age class, 65% to 77% of the attacked stands could contribute to mid-term timber supply. The surviving residual structure of young stands offers an opportunity to mitigate the effects of MPB-attack on future timber supply, increase age class diversity, and enhance ecological resilience in younger stands.

  14. Eletricidade Atmosférica e Fenômenos Correlatos

    OpenAIRE

    Tavares, M.; Santiago, M.A.M

    2002-01-01

    A qualquer momento, existem cerca de 2000 tempestades com relâmpagos nos cêus em torno do mundo. Estima-se que as tempestades combinadas produzem aproximadamente 100 descargas de raios por segundo, cada uma com temperatura em torno de 30.0000ºC - mais quente que a superfície do Sol. Esse trabalho apresenta aos leitores alguns fenômenos elêtricos na atmosfera e estratosfera. Tais eventos fazem parte de um sugerido circuito elêtrico atmosfêrico global e estão conectados à pesquisa de plasmas. A...

  15. Long-term impact of shoot blight disease on red pine saplings

    Science.gov (United States)

    Linda M. Haugen; Michael E. Ostry

    2013-01-01

    Damage from Sirococcus and Diplodia shoot blights of red pine is widespread and periodically severe in the Lake States. An outbreak of shoot blight occurred in red pine sapling plantations across northern Wisconsin, northern Minnesota, and the Upper Peninsula of Michigan in 1993. We established monitoring plots in red pine sapling...

  16. Fidelity of northern pine snakes (Pituophis m. melanoleucus) to natural and artificial hibernation sites in the New Jersey Pine Barrens.

    Science.gov (United States)

    Zappalorti, Robert T; Burger, Joanna; Burkett, David W; Schneider, David W; McCort, Matthew P; Golden, David M

    2014-01-01

    Environmental managers require information on whether human-made hibernacula are used by rare snakes before constructing large numbers of them as mitigation measures. Fidelity of northern pine snakes (Pituophis m. melanoleucus) was examined in a 6-year study in the New Jersey Pine Barrens to determine whether they used natural and artificial hibernacula equally. Pine snakes used both artificial (human-made) and natural (snake-adapted) hibernacula. Most natural hibernacula were in abandoned burrows of large mammals. Occupancy rates were similar between natural and artificial hibernacula. Only 6 of 27 radio-tracked snakes did not shift hibernacula between years, whereas 78% shifted sites at least once, and fidelity from one year to the next was 42%. For snakes that switched hibernacula (n = 21), one switched among artificial hibernacula, 14 (65%) switched among natural hibernacula, and 6 (29%) switched from artificial to natural hibernacula. Data indicate that most pine snakes switch among hibernacula, mainly selecting natural hibernacula, suggesting that artificial dens are used, but protecting natural hibernacula should be a higher conservation priority.

  17. Genome and transcriptome analyses of the mountain pine beetle-fungal symbiont Grosmannia clavigera, a lodgepole pine pathogen.

    Science.gov (United States)

    DiGuistini, Scott; Wang, Ye; Liao, Nancy Y; Taylor, Greg; Tanguay, Philippe; Feau, Nicolas; Henrissat, Bernard; Chan, Simon K; Hesse-Orce, Uljana; Alamouti, Sepideh Massoumi; Tsui, Clement K M; Docking, Roderick T; Levasseur, Anthony; Haridas, Sajeet; Robertson, Gordon; Birol, Inanc; Holt, Robert A; Marra, Marco A; Hamelin, Richard C; Hirst, Martin; Jones, Steven J M; Bohlmann, Jörg; Breuil, Colette

    2011-02-08

    In western North America, the current outbreak of the mountain pine beetle (MPB) and its microbial associates has destroyed wide areas of lodgepole pine forest, including more than 16 million hectares in British Columbia. Grosmannia clavigera (Gc), a critical component of the outbreak, is a symbiont of the MPB and a pathogen of pine trees. To better understand the interactions between Gc, MPB, and lodgepole pine hosts, we sequenced the ∼30-Mb Gc genome and assembled it into 18 supercontigs. We predict 8,314 protein-coding genes, and support the gene models with proteome, expressed sequence tag, and RNA-seq data. We establish that Gc is heterothallic, and report evidence for repeat-induced point mutation. We report insights, from genome and transcriptome analyses, into how Gc tolerates conifer-defense chemicals, including oleoresin terpenoids, as they colonize a host tree. RNA-seq data indicate that terpenoids induce a substantial antimicrobial stress in Gc, and suggest that the fungus may detoxify these chemicals by using them as a carbon source. Terpenoid treatment strongly activated a ∼100-kb region of the Gc genome that contains a set of genes that may be important for detoxification of these host-defense chemicals. This work is a major step toward understanding the biological interactions between the tripartite MPB/fungus/forest system.

  18. Landscape biology of western white pine: implications for conservation of a widely-distributed five-needle pine at its southern range limit

    Science.gov (United States)

    Patricia Maloney; Andrew Eckert; Detlev Vogler; Camille Jensen; Annette Delfino Mix; David Neale

    2016-01-01

    Throughout much of the range of western white pine, Pinus monticola Dougl., timber harvesting, fire exclusion and the presence of Cronartium ribicola J. C. Fisch., the white pine blister rust (WPBR) pathogen, have led to negative population and genetic consequences. To address these interactions, we examined population dynamics...

  19. Resistance to white pine blister rust in Pinus flexilis and P

    Science.gov (United States)

    Anna W. Schoettle; Richard A. Sniezko; Angelia Kegley; Jerry Hill; Kelly S. Burns

    2010-01-01

    The non-native fungus Cronartium ribicola, that causes white pine blister rust (WPBR), is impacting or threatening limber pine, Pinus flexilis, and Rocky Mountain bristlecone pine, Pinus aristata. In the Southern Rockies, where the rust invasion is still expanding, we have the opportunity to be proactive and prepare the landscape for invasion. Genetic...

  20. Grazing on Regeneration Sites Encourages Pine Seedling Growth

    Science.gov (United States)

    Raymond D. Ratliff; Renee G. Denton

    1995-01-01

    Effects of season-long, deferred-rotation, and rest-rotation grazing, on ponderosa pine (Pinus ponderosa Dougl. ex Laws.) seedling growth and herbaceous vegetation control were studied in regeneration sites at Boyd Hill, Modoc National Forest, California. Seedlings were planted in 1989. Pine seedling survival and damage did not differ, but the...

  1. Modifications in pine (Pinus silvestris) under the impact of industrial air pollution

    Energy Technology Data Exchange (ETDEWEB)

    Wolak, J

    1970-01-01

    Growth habit forms in pine which developed in the Upper Silesian Industrial Region in places where industrial air pollution is a dominant ecological factor are described. Juvenile pine individuals, when not growing in density, soon cease to grow in height and their lateral branches grow freely while creeping on ground. In contrast to lifted up branches which are invaded by pests, those creeping one are healthy, with great increment, healthy needles, and normally developed cones. Pine shrubs acquire the habit of mountain pine. In pine shrubs there is formed the plant association Pinus silvestris-Solanum dulcamara which is not to be found elsewhere. When air pollution reaches its threshold value, when pine trees have no lower verticils, then upper branches grow downward until they reach soil surface and creep on it similarly as in the former case. The phenomenon of the formation of genuine habit forms in pine is one of the symptoms of impairment of productive capacity of habitat under the impact of the industrial air pollution.

  2. Response of Korean pine's functional traits to geography and climate.

    Directory of Open Access Journals (Sweden)

    Yichen Dong

    Full Text Available This study analyzed the characteristics of Korean pine (Pinus koraiensis functional trait responses to geographic and climatic factors in the eastern region of Northeast China (41°-48°N and the linear relationships among Korean pine functional traits, to explore this species' adaptability and ecological regulation strategies under different environmental conditions. Korean pine samples were collected from eight sites located at different latitudes, and the following factors were determined for each site: geographic factors-latitude, longitude, and altitude; temperature factors-mean annual temperature (MAT, growth season mean temperature (GST, and mean temperature of the coldest month (MTCM; and moisture factors-annual precipitation (AP, growth season precipitation (GSP, and potential evapotranspiration (PET. The Korean pine functional traits examined were specific leaf area (SLA, leaf thickness (LT, leaf dry matter content (LDMC, specific root length (SRL, leaf nitrogen content (LNC, leaf phosphorus content (LPC, root nitrogen content (RNC, and root phosphorus content (RPC. The results showed that Korean pine functional traits were significantly correlated to latitude, altitude, GST, MTCM, AP, GSP, and PET. Among the Korean pine functional traits, SLA showed significant linear relationships with LT, LDMC, LNC, LPC, and RPC, and LT showed significant linear relationships with LDMC, SRL, LNC, LPC, RNC, and RPC; the linear relationships between LNC, LPC, RNC, and RPC were also significant. In conclusion, Korean pine functional trait responses to latitude resulted in its adaptation to geographic and climatic factors. The main limiting factors were precipitation and evapotranspiration, followed by altitude, latitude, GST, and MTCM. The impacts of longitude and MAT were not obvious. Changes in precipitation and temperature were most responsible for the close correlation among Korean pine functional traits, reflecting its adaption to habitat

  3. Climate Change Altered Disturbance Regimes in High Elevation Pine Ecosystems

    Science.gov (United States)

    Logan, J. A.

    2004-12-01

    Insects in aggregate are the greatest cause of forest disturbance. Outbreaks of both native and exotic insects can be spectacular events in both their intensity and spatial extent. In the case of native species, forest ecosystems have co-evolved (or at least co-adapted) in ways that incorporate these disturbances into the normal cycle of forest maturation and renewal. The time frame of response to changing climate, however, is much shorter for insects (typically one year) than for their host forests (decades or longer). As a result, outbreaks of forest insects, particularly bark beetles, are occurring at unprecedented levels throughout western North America, resulting in the loss of biodiversity and potentially entire ecosystems. In this talk, I will describe one such ecosystem, the whitebark pine association at high elevations in the north-central Rocky Mountains of the United States. White bark pines are keystone species, which in consort with Clark's nutcracker, build entire ecosystems at high elevations. These ecosystems provide valuable ecological services, including the distribution and abundance of water resources. I will briefly describe the keystone nature of whitebark pine and the historic role of mountain pine beetle disturbance in these ecosystems. The mountain pine beetle is the most important outbreak insect in forests of the western United States. Although capable of spectacular outbreak events, in historic climate regimes, outbreak populations were largely restricted to lower elevation pines; for example, lodgepole and ponderosa pines. The recent series of unusually warm years, however, has allowed this insect to expand its range into high elevation, whitebark pine ecosystems with devastating consequences. The aspects of mountain pine beetle thermal ecology that has allowed it to capitalize so effectively on a warming climate will be discussed. A model that incorporates critical thermal attributes of the mountain pine beetle's life cycle was

  4. On the relative contributions of wind vs. animals to seed dispersal of four Sierra Nevada pines.

    Science.gov (United States)

    Vander Wall, Stephen B

    2008-07-01

    Selective pressures that influence the form of seed dispersal syndromes are poorly understood. Morphology of plant propagules is often used to infer the means of dispersal, but morphology can be misleading. Several species of pines, for example, have winged seeds adapted for wind dispersal but owe much of their establishment to scatter-hoarding animals. Here the relative importance of wind vs. animal dispersal is assessed for four species of pines of the eastern Sierra Nevada that have winged seeds but differed in seed size: lodgepole pine (Pinus contorta murrayana, 8 mg); ponderosa pine (Pinus ponderosa ponderosa, 56 mg); Jeffrey pine (Pinus jeffreyi, 160 mg); and sugar pine (Pinus lambertiana, 231 mg). Pre-dispersal seed mortality eliminated much of the ponderosa pine seed crop (66%), but had much less effect on Jeffrey pine (32% of seeds destroyed), lodgepole pine (29%), and sugar pine (7%). When cones opened most filled seeds were dispersed by wind. Animals removed > 99% of wind-dispersed Jeffrey and sugar pine seeds from the ground within 60 days, but animals gathered only 93% of lodgepole pine seeds and 38% of ponderosa pine seeds during the same period. Animals gathered and scatter hoarded radioactively labeled ponderosa, Jeffrey, and sugar pine seeds, making a total of 2103 caches over three years of study. Only three lodgepole pine caches were found. Caches typically contained 1-4 seeds buried 5-20 mm deep, depths suitable for seedling emergence. Although Jeffrey and sugar pine seeds are initially wind dispersed, nearly all seedlings arise from animal caches. Lodgepole pine is almost exclusively wind dispersed, with animals acting as seed predators. Animals treated ponderosa pine in an intermediate fashion. Two-phased dispersal of large, winged pine seeds appears adaptive; initial wind dispersal helps to minimize pre-dispersal seed mortality whereas scatter hoarding by animals places seeds in sites with a higher probability of seedling establishment.

  5. Interacting effects of sulphate pollution, sulphide toxicity and eutrophication on vegetation development in fens: A mesocosm experiment

    International Nuclear Information System (INIS)

    Geurts, Jeroen J.M.; Sarneel, Judith M.; Willers, Bart J.C.; Roelofs, Jan G.M.; Verhoeven, Jos T.A.; Lamers, Leon P.M.

    2009-01-01

    Both eutrophication and SO 4 pollution can lead to higher availability of nutrients and potentially toxic compounds in wetlands. To unravel the interaction between the level of eutrophication and toxicity at species and community level, effects of SO 4 were tested in nutrient-poor and nutrient-rich fen mesocosms. Biomass production of aquatic and semi-aquatic macrophytes and colonization of the water layer increased after fertilization, leading to dominance of highly competitive species. SO 4 addition increased alkalinity and sulphide concentrations, leading to decomposition and additional eutrophication. SO 4 pollution and concomitant sulphide production considerably reduced biomass production and colonization, but macrophytes were less vulnerable in fertilized conditions. The experiment shows that competition between species, vegetation succession and terrestrialization are not only influenced by nutrient availability, but also by toxicity, which strongly interacts with the level of eutrophication. This implies that previously neutralized toxicity effects in eutrophied fens may appear after nutrient reduction measures have been taken. - Interspecific competition, vegetation succession and terrestrialization in fens depend on the interacting effects of SO 4 pollution, sulphide toxicity and nutrient availability.

  6. Weathering the storm: how lodgepole pine trees survive mountain pine beetle outbreaks.

    Science.gov (United States)

    Erbilgin, Nadir; Cale, Jonathan A; Hussain, Altaf; Ishangulyyeva, Guncha; Klutsch, Jennifer G; Najar, Ahmed; Zhao, Shiyang

    2017-06-01

    Recent mountain pine beetle outbreaks in western North America killed millions of lodgepole pine trees, leaving few survivors. However, the mechanism underlying the ability of trees to survive bark beetle outbreaks is unknown, but likely involve phytochemicals such as monoterpenes and fatty acids that can drive beetle aggregation and colonization on their hosts. Thus, we conducted a field survey of beetle-resistant lodgepole pine (Pinus contorta) trees to retrospectively deduce whether these phytochemicals underlie their survival by comparing their chemistry to that of non-attacked trees in the same stands. We also compared beetle attack characteristics between resistant and beetle-killed trees. Beetle-killed trees had more beetle attacks and longer ovipositional galleries than resistant trees, which also lacked the larval establishment found in beetle-killed trees. Resistant trees contained high amounts of toxic and attraction-inhibitive compounds and low amounts of pheromone-precursor and synergist compounds. During beetle host aggregation and colonization, these compounds likely served three critical roles in tree survival. First, low amounts of pheromone-precursor (α-pinene) and synergist (mycrene, terpinolene) compounds reduced or prevented beetles from attracting conspecifics to residual trees. Second, high amounts of 4-allyanisole further inhibited beetle attraction to its pheromone. Finally, high amounts of toxic limonene, 3-carene, 4-allyanisole, α-linolenic acid, and linoleic acid inhibited beetle gallery establishment and oviposition. We conclude that the variation of chemotypic expression of local plant populations can have profound ecological consequences including survival during insect outbreaks.

  7. Limber pine seed and seedling planting experiment in Waterton Lakes National Park, Canada

    Science.gov (United States)

    Cyndi M. Smith; Graeme Poll; Cameron Gillies; Celina Praymak; Eileen Miranda; Justin Hill

    2011-01-01

    Limber pine plays an important role in the harsh environments in which it lives, providing numerous ecological services, especially because its large, wingless seeds serve as a high energy food source for many animals. Limber pine populations are declining due to a combination of white pine blister rust, mountain pine beetle, drought, and fire suppression. Outplanting...

  8. Host Defense Mechanisms against Bark Beetle Attack Differ between Ponderosa and Lodgepole Pines

    Directory of Open Access Journals (Sweden)

    Daniel R. West

    2016-10-01

    Full Text Available Conifer defenses against bark beetle attack include, but are not limited to, quantitative and qualitative defenses produced prior to attack. Our objective was to assess host defenses of lodgepole pine and ponderosa pine from ecotone stands. These stands provide a transition of host species for mountain pine beetle (Dendroctonus ponderosae; MPB. We asked two questions: (1 do the preformed quantitative host defenses (amount of resin and (2 the preformed qualitative host defenses (monoterpene constituents differ between lodgepole and ponderosa pines. We collected oleoresins at three locations in the Southern Rocky Mountains from 56 pairs of the pine species of similar size and growing conditions. The amount of preformed-ponderosa pine oleoresins exuded in 24 h (mg was almost four times that of lodgepole pine. Total qualitative preformed monoterpenes did not differ between the two hosts, though we found differences in all but three monoterpenes. No differences were detected in α-pinene, γ-terpinene, and bornyl acetate. We found greater concentrations of limonene, β-phellandrene, and cymene in lodgepole pines, whereas β-pinene, 3-carene, myrcene, and terpinolene were greater in ponderosa pine. Although we found differences both in quantitative and qualitative preformed oleoresin defenses, the ecological relevance of these differences to bark beetle susceptibility have not been fully tested.

  9. Limonene: attractant kairomone for white pine cone beetles (Coleoptera: Scolytidae) in an Eastern white pine seed orchard in Western North Carolina

    Science.gov (United States)

    Daniel R. Miller

    2007-01-01

    I report on the attraction of the white pine cone beetle, Canophthorus coniperda (Schwarz) (Coleoptera: Scolytidae), to traps baited with the host monoterpene limonene in western North Carolina. Both (+)- and (-)-limonene attracted male and female cone beetles to Japenese beetle traps in an eastern white pine, Pinus strobus L. seed...

  10. Soil Preferences in Germination and Survival of Limber Pine in the Great Basin White Mountains

    Directory of Open Access Journals (Sweden)

    Brian V. Smithers

    2017-11-01

    Full Text Available In the Great Basin, limber pine is a sub-alpine tree species that is colonizing newly available habitat above treeline in greater numbers than treeline-dominating Great Basin bristlecone pine, especially on dolomite soil, where few plants are able to grow and where limber pine adults are rare. To examine the role of soil type on germination and establishment of limber pine, I sowed limber pine seeds in containers of the three main White Mountains soil types in one location while measuring soil moisture and temperature. I found that dolomite soil retains water longer, and has higher soil water content, than quartzite and granite soils and has the coolest maximum growing season temperatures. Limber pine germination and survival were highest in dolomite soil relative to quartzite and granite where limber pine adults are more common. While adult limber pines are rare on dolomite soils, young limber pines appear to prefer them. This indicates that limber pine either has only recently been able to survive in treeline climate on dolomite or that bristlecone pine has some long-term competitive advantage on dolomite making limber pine, a species with 1500 year old individuals, an early succession species in Great Basin sub-alpine forests.

  11. Financial performance of loblolly and longleaf pine plantations

    Science.gov (United States)

    Steven D. Mills; Charles T. Stiff

    2013-01-01

    The financial performance of selected management regimes for loblolly (Pinus taeda L.) and longleaf pine (P. palustris Mill.) plantations were compared for four cases, each with low- and high-site productivity levels and each evaluated using 5 and 7 percent real discount rates. In all cases, longleaf pine was considered both with...

  12. Produção de mudas de cultivares de alface utilizando duas espumas fenólicas em Altamira, Pará

    Directory of Open Access Journals (Sweden)

    Alzirio Lino Couto

    2015-06-01

    Full Text Available O sucesso de qualquer produção comercial de hortaliças inicia-se com a produção de mudas. A espuma fenólica tem se mostrado um interessante e prático substrato para este processo. A utilização deste produto depende de uma lavagem precedente para reduzir a acidez. Porém, já é possível encontrar à venda espumas fenólicas com pH próximo. Por isso o objetivo deste trabalho foi avaliar a produção de mudas de cultivares de alface utilizando duas espumas fenólicas em Altamira, Pará. O delineamento constou de um esquema fatorial 2 (substratos x 6 (cultivares. Os dois substratos foram as espumas fenólicas Green Up®, com pH 6.0 (± 0.5., e a outra com pH 2.6 (± 0.5. As cultivares avaliadas foram: Alcione, Amanda, Lucy Brown, Caipira, Multiblond 3 e Solaris. Foi avaliada porcentagem de germinação, índice de velocidade de emergência, altura da planta e número de folhas. Houve diferença significativa para altura da planta em função dos substratos testados. A porcentagem de germinação mais elevada foi obtida com a espuma fenólica sem tratamento. A cultivar Caipira foi a que teve o menor desempenho na germinação. Para todas as variáveis analisadas, a cultivar Lucy Brown apresentou os melhores resultados em ambos os substratos.

  13. Net ecosystem exchange in a sedge-sphagnum fen at the South of West Siberia, Russia

    Science.gov (United States)

    Dyukarev, Egor

    2017-04-01

    The model of net ecosystem exchange was used to study the influence of different environmental factors and to calculate daily and growing season carbon budget for minerotrophic fen at South of West Siberia, Russia. Minerotrophic sedge-sphagnum fen occupies the central part of the Bakcharskoe bog. The model uses air and soil temperature, incoming photosynthetically active radiation, and leaf area index as the explanatory factors for gross primary production, heterotrophic and autotrophic respiration. The model coefficients were calibrated using data collected by automated soil CO2 flux system with clear long-term chamber. The studied ecosystem is a sink of carbon according to modelling and observation results. This study was supported by Russian Foundation for Basic Researches (grant numbers 16-07-01205 and 16-45-700562.

  14. The state of mixed shortleaf pine-upland oak management in Missouri

    Science.gov (United States)

    Elizabeth M. Blizzard; David R. Larsen; Daniel C. Dey; John M. Kabrick; David Gwaze

    2007-01-01

    Mixed shortleaf pine-upland oak stands allow flexibility in type and timing of regeneration, release, and harvesting treatments for managers; provide unique wildlife and herbaceous community niches; and increase visual diversity. Most of the research to date focused on growing pure pine or oak stands, with little research on today's need to grow pine-oak mixtures...

  15. Mapping pine mortality by aerial photography, Umstead State Park, North Carolina

    Science.gov (United States)

    Clarence J. DeMars; Garey W. Slaughter; Lnla E. Greene; John H. Ghent

    1982-01-01

    In 1975-1976, pine trees killed by the southern pine beetle Dendroctonus frontalis Zimm.) in a 2l70-hectare (5362-acre) area at the William B. Umstead State Park in central North Carolina, were monitored by sequential color infrared aerial photography. From 1973 through summer 1975, beetles in 350 infestation spots killed more than 20,500 pines on...

  16. Red-cockaded woodpecker nestling provisioning and reproduction in two different pine habitats

    Science.gov (United States)

    Richard R. Schaefer; Richard N. Conner; D. Craig Rudolph; Daniel Saenz

    2004-01-01

    We obtained nestling provisioning and rcpntductive data from 24 Red-cockaded Woodpecker (Picoides borealis) groups occupying two different pine habitats-longleaf pine (Pinus palustris) and a mixture of loblolly (P. taeda) and shortleaf pine (P. echinata)--in eastern Texas during 1990 and 1901....

  17. The bioconversion of mountain pine beetle-killed lodgepole pine to fuel ethanol using the organosolv process.

    Science.gov (United States)

    Pan, Xuejun; Xie, Dan; Yu, Richard W; Saddler, Jack N

    2008-09-01

    Lodgepole pine (Pinus contorta) killed by mountain pine beetle (Dendroctonus ponderosae) (BLP) was compared with healthy lodgepole pine (HLP) for bioconversion to ethanol and high-value co-products. The BLP and HLP chips were pretreated using an ethanol organosolv process at a variety of severities. It was shown that the BLP was easier to pretreat and delignify than were the HLP chips. The resulting pretreated BLP substrate had a lower residual lignin, lower degree of polymerization of cellulose, lower cellulose crystallinity, smaller fiber size and thereby a better enzymatic hydrolysability than did the HLP substrates. However, under the same conditions, the BLP showed lower substrate yield and cellulose recovery than did the HLP, which likely resulted from the excessive hydrolysis and subsequent decomposition of the cellulose and hemicellulose during the pretreatment. The BLP wood yielded more ethanol organosolv lignin than was obtained with the HLP material. The HLP lignin had a lower molecular weight and narrower distribution than did the BLP lignin. It appears that the beetle killed LP is more receptive to organosolv pretreatment other than a slightly lower recovery of carbohydrates.

  18. Measurement of 54Fe(n,2n)53Fe cross section near threshold

    International Nuclear Information System (INIS)

    Smither, R.K.; Greenwood, L.R.

    1984-01-01

    A series of experiments were performed at the Princeton Plasma Physics Laboratory to measure the cross section of the 54 Fe(n,2n) 53 Fe reaction near threshold. Measurements were made at 6 different neutron energies and cover the 1 MeV energy range from threshold (13.64 MeV) to 14.64 MeV. The 54 Fe(n,2n) cross section was measured relative to the 27 Al(n,p) 27 Mg cross section to an accuracy of a few percent. These accurate cross-section measurements will be useful in calculating damage caused by 14 MeV D-T plasma neutrons in Fe and calculating the production of the long-lived 53 Mn nuclei that account for much of the buildup of long-lived radioactivity in steel structures and other ferrous materials used in the construction of fusion reactors. They will also play an important part in a new method for measuring the plasma ion temperature of a D-T plasma

  19. Vegetation composition and structure of southern coastal plain pine forests: An ecological comparison

    Science.gov (United States)

    Hedman, C.W.; Grace, S.L.; King, S.E.

    2000-01-01

    Longleaf pine (Pinus palustris) ecosystems are characterized by a diverse community of native groundcover species. Critics of plantation forestry claim that loblolly (Pinus taeda) and slash pine (Pinus elliottii) forests are devoid of native groundcover due to associated management practices. As a result of these practices, some believe that ecosystem functions characteristic of longleaf pine are lost under loblolly and slash pine plantation management. Our objective was to quantify and compare vegetation composition and structure of longleaf, loblolly, and slash pine forests of differing ages, management strategies, and land-use histories. Information from this study will further our understanding and lead to inferences about functional differences among pine cover types. Vegetation and environmental data were collected in 49 overstory plots across Southlands Experiment Forest in Bainbridge, GA. Nested plots, i.e. midstory, understory, and herbaceous, were replicated four times within each overstory plot. Over 400 species were identified. Herbaceous species richness was variable for all three pine cover types. Herbaceous richness for longleaf, slash, and loblolly pine averaged 15, 13, and 12 species per m2, respectively. Longleaf pine plots had significantly more (p < 0.029) herbaceous species and greater herbaceous cover (p < 0.001) than loblolly or slash pine plots. Longleaf and slash pine plots were otherwise similar in species richness and stand structure, both having lower overstory density, midstory density, and midstory cover than loblolly pine plots. Multivariate analyses provided additional perspectives on vegetation patterns. Ordination and classification procedures consistently placed herbaceous plots into two groups which we refer to as longleaf pine benchmark (34 plots) and non-benchmark (15 plots). Benchmark plots typically contained numerous herbaceous species characteristic of relic longleaf pine/wiregrass communities found in the area. Conversely

  20. Severe burning treatment tested on lowland pine sites

    Science.gov (United States)

    S. Little; E. B. Moore

    1953-01-01

    Since the prescribed use of fire is a fairly new silvicultural technique for preparing seedbeds for pine in the New Jersey pine region, it has been used rather cautiously. Burning treatments have been made in the winter, when periodic light fires can be easily controlled. The treatments have been used almost exclusively on upland sites.

  1. Development of a pathway model to assess the exposure of European pine trees to pine wood nematode via the trade of wood

    NARCIS (Netherlands)

    Douma, J.C.; Werf, Van Der W.; Hemerik, L.; Magnusson, C.; Robinet, C.

    2017-01-01

    Pine wood nematode (PWN), Bursaphelenchus xylophilus, is a threat for pine species (Pinus spp.) throughout the world. The nematode is native to North America, and invaded Japan, China, Korea, and Taiwan, and more recently Portugal and Spain. PWN enters new areas through trade in wood products. Once

  2. Water level, vegetation composition, and plant productivity explain greenhouse gas fluxes in temperate cutover fens after inundation

    Science.gov (United States)

    Minke, Merten; Augustin, Jürgen; Burlo, Andrei; Yarmashuk, Tatsiana; Chuvashova, Hanna; Thiele, Annett; Freibauer, Annette; Tikhonov, Vitalij; Hoffmann, Mathias

    2016-07-01

    Peat extraction leaves a land surface with a strong relief of deep cutover areas and higher ridges. Rewetting inundates the deep parts, while less deeply extracted zones remain at or above the water level. In temperate fens the flooded areas are colonized by helophytes such as Eriophorum angustifolium, Carex spp., Typha latifolia or Phragmites australis dependent on water depth. Reeds of Typha and Phragmites are reported as large sources of methane, but data on net CO2 uptake are contradictory for Typha and rare for Phragmites. Here, we analyze the effect of vegetation, water level and nutrient conditions on greenhouse gas (GHG) emissions for representative vegetation types along water level gradients at two rewetted cutover fens (mesotrophic and eutrophic) in Belarus. Greenhouse gas emissions were measured campaign-wise with manual chambers every 2 to 4 weeks for 2 years and interpolated by modelling. All sites had negligible nitrous oxide exchange rates. Most sites were carbon sinks and small GHG sources. Methane emissions generally increased with net ecosystem CO2 uptake. Mesotrophic small sedge reeds with water table around the land surface were small GHG sources in the range of 2.3 to 4.2 t CO2 eq. ha-1 yr-1. Eutrophic tall sedge - Typha latifolia reeds on newly formed floating mats were substantial net GHG emitters in the range of 25.1 to 39.1 t CO2 eq. ha-1 yr. They represent transient vegetation stages. Phragmites reeds ranged between -1.7 to 4.2 t CO2 eq. ha-1 yr-1 with an overall mean GHG emission of 1.3 t CO2 eq. ha-1 yr-1. The annual CO2 balance was best explained by vegetation biomass, which includes the role of vegetation composition and species. Methane emissions were obviously driven by biological activity of vegetation and soil organisms. Shallow flooding of cutover temperate fens is a suitable measure to arrive at low GHG emissions. Phragmites australis establishment should be promoted in deeper flooded areas and will lead to moderate, but

  3. The push-pull tactic for mitigation of mountain pine beetle (Coleoptera: Curculionidae) damage in lodgepole and whitebark pines.

    Science.gov (United States)

    Gillette, Nancy E; Mehmel, Constance J; Mori, Sylvia R; Webster, Jeffrey N; Wood, David L; Erbilgin, Nadir; Owen, Donald R

    2012-12-01

    In an attempt to improve semiochemical-based treatments for protecting forest stands from bark beetle attack, we compared push-pull versus push-only tactics for protecting lodgepole pine (Pinus contorta Douglas ex Loudon) and whitebark pine (Pinus albicaulis Engelm.) stands from attack by mountain pine beetle (Dendroctonus ponderosae Hopkins) in two studies. The first was conducted on replicated 4.04-ha plots in lodgepole pine stands (California, 2008) and the second on 0.81-ha plots in whitebark pine stands (Washington, 2010). In both studies, D. ponderosae population levels were moderate to severe. The treatments were 1) push-only (D. ponderosae antiaggregant semiochemicals alone); 2) push-pull (D. ponderosae antiaggregants plus perimeter traps placed at regular intervals, baited with four-component D. ponderosae aggregation pheromone); and 3) untreated controls. We installed monitoring traps baited with two-component D. ponderosae lures inside each plot to assess effect of treatments on beetle flight. In California, fewer beetles were collected in push-pull treated plots than in control plots, but push-only did not have a significant effect on trap catch. Both treatments significantly reduced the rate of mass and strip attacks by D. ponderosae, but the difference in attack rates between push-pull and push-only was not significant. In Washington, both push-pull and push-only treatments significantly reduced numbers of beetles caught in traps. Differences between attack rates in treated and control plots in Washington were not significant, but the push-only treatment reduced attack rates by 30% compared with both the control and push-pull treatment. We conclude that, at these spatial scales and beetle densities, push-only may be preferable for mitigating D. ponderosae attack because it is much less expensive, simpler, and adding trap-out does not appear to improve efficacy.

  4. A first principles calculations of structural, electronic, magnetic and dynamical properties of mononitrides FeN and CoN

    International Nuclear Information System (INIS)

    Soni, Himadri R.; Mankad, Venu; Gupta, Sanjeev K.; Jha, Prafulla K.

    2012-01-01

    Highlights: ► We present spin dependent bandstructure, structural and magnetic moment of FeN/CoN. ► The PDC, PHDOS, spin effect on phonons suggests ZB is preferred at ambient pressure. ► Spin calculation offers an opportunity to understand the role of spin on phonons. - Abstract: Using first principles density functional theoretical calculations, the present paper reports a systematic nonspin and spin polarized total energy calculations of the lattice dynamical and a number of other properties such as band structure, structural and magnetic moment of two mononitrides FeN and CoN. The phonon dispersion curves and phonon density of states in the case of FeN and CoN have been determined for the first time and discussed. The structural and dynamical calculations suggest that the zinc blende structure is preferred at ambient pressure for both compounds. The rocksalt FeN has a nonzero magnetic moment while for FeN in zinc blende phase, it is either zero or very small. The zinc blende phase for both compounds is nonmagnetic. The spin calculation offers an intensive opportunity to understand the role of spin on the phonon properties of two mononitrides. Majority of the modes are sensitive to the effect of spin due to the modification of lattice constant. In this work we reveal that spin modifies the interionic interactions and local structure and leads to a flexible lattice which can be used for the functional materials design.

  5. Landscape Biology of Western White Pine: Implications for Conservation of a Widely-Distributed Five-Needle Pine at Its Southern Range Limit

    Directory of Open Access Journals (Sweden)

    Patricia E. Maloney

    2016-04-01

    Full Text Available Throughout much of the range of western white pine, Pinus monticola Dougl., timber harvesting, fire exclusion and the presence of Cronartium ribicola J. C. Fisch., the white pine blister rust (WPBR pathogen, have led to negative population and genetic consequences. To address these interactions, we examined population dynamics and genetic diversity in 10 populations of western white pine in upper montane forests of the Lake Tahoe Basin. We documented negative population trends for three of the 10 populations. These populations exhibited low estimated growth rates (λ, moderate to high incidences of WPBR and mountain pine beetle (MPB, and high levels of mortality. In contrast, seven populations appear to be stable (λ ≥ 1.0, with low to moderate disease and insect incidence, and evidence for genetic resistance to WPBR. Genetic diversity (HE for a set of 160 single nucleotide polymorphisms was in the range of 0.245–0.272 across populations, and population-specific estimates of FST ranged from 0.0062 to 0.0244. Allele frequency of the Cr2 gene, which confers complete resistance to C. ribicola in western white pine, was low, averaging 0.009 for all populations sampled. However, a low frequency of pollen receptors (i.e., susceptible maternal parents pollinated by a local resistant parent was found in nine of 10 populations. A moderate and negative relationship was found between the frequency of pollen receptors in a population and the incidence of WPBR (r2 = 0.32. In the context of an introduced pathogen, climate driven outbreaks of MPB, fire exclusion, and prolonged drought, conservation and management strategies are warranted for this species in the Lake Tahoe Basin and likely other locations in California. These strategies include gene conservation of western white pine, WPBR resistance screening, and forest restoration treatments.

  6. Investigation of environmental pollution with pine needles by NAA

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kil Yong; Yoon, Yoon Yeol; Yang, Myung Kwon; Shim, Sang Kwon; Seo, Bum Kyoung [Korea Inst. of Geosience and Mineral Resources, Environmental Geology Division, Daejeon (Korea); Chung, Yong Sam [Korea Atomic Energy Research Inst., HANARO Center, Daejeon (Japan)

    2002-04-01

    NAA was studied to precision analysis of metallic elements in pine needle. The pine needle was investigated whether it can be feasible or not as a bio-monitor. Only one year old needle was taken from three different regions of urban, suburban and rural area in four seasons. The needle sample was divided with two aliquots, and then one was cleaned and the other was not. Loss and contamination of analytes were cautiously minimized when the needle was sample and transferred from mountain to laboratory and prepared for NAA. Some elements such as As, Br, Ce, W, Zn have shown different characteristics with regions and seasons as well as surface cleaning. It is found that about twenty elements in pine needle could be simply analyzed by NAA and the pine needle could be suitable as a bio-monitor for the monitoring of environmental pollution in Korea. (author)

  7. The status of our scientific understanding of lodgepole pine and mountain pine beetles - a focus on forest ecology and fire behavior

    Science.gov (United States)

    Merrill R. Kaufmann; Gregory H. Aplet; Michael G. Babler; William L. Baker; Barbara Bentz; Michael Harrington; Brad C. Hawkes; Laurie Stroh Huckaby; Michael J. Jenkins; Daniel M. Kashian; Robert E. Keane; Dominik Kulakowski; Ward McCaughey; Charles McHugh; Jose Negron; John Popp; William H. Romme; Wayne Shepperd; Frederick W. Smith; Elaine Kennedy Sutherland; Daniel Tinker; Thomas T. Veblen

    2008-01-01

    Mountain pine beetle populations have reached outbreak levels in lodgepole pine forests throughout North America. The geographic focus of this report centers on the southern Rocky Mountains of Colorado and southern Wyoming. The epidemic extends much more widely, however, from the southern Rocky Mountains in Colorado in the United States to the northern Rocky Mountains...

  8. Possibilities of breeding weevil-resistant white pine strains

    Science.gov (United States)

    Jonathan W. Wright; William J. Gabriel

    1959-01-01

    Eastern white pine (Pinus strobus L.) is a highly versatile species. It is easily planted, adaptable to a wide variety of soils and climates, and reproduces itself well. Also it grows rapidly and is capable of producing high-quality lumber. These characteristics once entitled white pine to a top position in the forest economy throughout much of the...

  9. Overhead shading and growth of young longleaf pine

    Science.gov (United States)

    John C. Gilbert; John S. Kush; Ralph S. Meldahl; William D. Boyer; Dean H. Gjerstad

    2014-01-01

    A study to determine the effects of environmental conditions on the growth of longleaf pine (Pinus palustris Mill.) was initiated in 1969 on the Escambia Experimental Forest near Brewton, Alabama, USA. This study sample consisted of forty young naturally regenerated, even aged longleaf pine seedlings evenly divided between two soil types. At the beginning of the study...

  10. Straight studs are produced from southern pine cordwood

    Science.gov (United States)

    Peter Koch

    1967-01-01

    A Process for converting southern pine veneer cores into 8-foot 2 by 4's of SPIB Stud grade and better has been developed at the Alexandria, Louisiana, Utilization Laboratory of the Southern Forest Experiment Station. The research leading to this development suggests that a similiar process would be practical for converting 8-foot southern pine cordwood into studs...

  11. O fenómeno do Fansubbing em inglês: principais normas de tradução e legendagem

    OpenAIRE

    Sousa, Inês Fernandes e

    2011-01-01

    Tese de mestrado, Tradução, Universidade de Lisboa, Faculdade de Letras, 2012 Este trabalho enquadra-se no âmbito dos Estudos Descritivos de Tradução, mais concretamente, nos conceitos de norma e estratégia de tradução e teve como objectivo estudar algumas das principais estratégias e regularidades evidenciadas pelo fenómeno de “fansubbing”. Este fenómeno corresponde ao trabalho de equipas amadoras especializadas na tradução para legendagem predominantemente em inglês de desenh...

  12. Metódica: Articulación sistema teórico, fenómeno y procesos en el objeto de estudio. Una perspectiva desde el fenómeno pobreza

    Directory of Open Access Journals (Sweden)

    Yajaira Jiménez Zabala

    2011-10-01

    Full Text Available En este artículo discutimos la visión metódica que toma como apoyo el pivote entre lo cualitativo, lo cuantitativo y el orden de complejidad, en un enfoque plurimetódico, a través del cual se construyó la visión de la pobreza como objeto de estudio. Tal selección, está justificada en tanto se entiende la pobreza como un fenómeno social complejo, por las diversas aristas que le identifican. La combinación de los enfoques metodológicos permitió la aprehensión de los diferentes aspectos del fenómeno y de sus interrelaciones en las representaciones de los actores sociales vinculados con el estudio. Lo cualitativo, se entiende como la simbiosis de prácticas interpretativas, que no privilegia una metodología sobre otra. Lo cuantitativo estuvo referido al uso de indicadores derivados de los soportes referenciales del problema; el orden de complejidad, atendió a la manifestación de lo simple en tanto nodo tensional complejo, que requiere una mirada diferente para su comprensión e interpretación.

  13. Differentiating needle blights of white pine in the interpretation of fume damage

    Energy Technology Data Exchange (ETDEWEB)

    Hepting, G H; Berry, C R

    1961-01-01

    In white pines it is difficult to differentiate between needle blight caused by air pollution and numerous other causes. White pines are regarded as sensitive to sulfur dioxide and fluorine. The authors attempt to provide means of identifying and separating blights of white pines in the southern Appalachians.

  14. A decade of boreal rich fen greenhouse gas fluxes in response to natural and experimental water table variability

    Science.gov (United States)

    Olefeldt, David; Euskirchen, Eugénie S.; Harden, Jennifer W.; Kane, Evan S.; McGuire, A. David; Waldrop, Mark P.; Turetsky, Merritt R.

    2017-01-01

    Rich fens are common boreal ecosystems with distinct hydrology, biogeochemistry and ecology that influence their carbon (C) balance. We present growing season soil chamber methane emission (FCH4), ecosystem respiration (ER), net ecosystem exchange (NEE) and gross primary production (GPP) fluxes from a 9-years water table manipulation experiment in an Alaskan rich fen. The study included major flood and drought years, where wetting and drying treatments further modified the severity of droughts. Results support previous findings from peatlands that drought causes reduced magnitude of growing season FCH4, GPP and NEE, thus reducing or reversing their C sink function. Experimentally exacerbated droughts further reduced the capacity for the fen to act as a C sink by causing shifts in vegetation and thus reducing magnitude of maximum growing season GPP in subsequent flood years by ~15% compared to control plots. Conversely, water table position had only a weak influence on ER, but dominant contribution to ER switched from autotrophic respiration in wet years to heterotrophic in dry years. Droughts did not cause inter-annual lag effects on ER in this rich fen, as has been observed in several nutrient-poor peatlands. While ER was dependent on soil temperatures at 2 cm depth, FCH4 was linked to soil temperatures at 25 cm. Inter-annual variability of deep soil temperatures was in turn dependent on wetness rather than air temperature, and higher FCH4 in flooded years was thus equally due to increased methane production at depth and decreased methane oxidation near the surface. Short-term fluctuations in wetness caused significant lag effects on FCH4, but droughts caused no inter-annual lag effects on FCH4. Our results show that frequency and severity of droughts and floods can have characteristic effects on the exchange of greenhouse gases, and emphasize the need to project future hydrological regimes in rich fens.

  15. Composição fenólica de ligninas dioxano determinadas pela reação oxidativa com o nitrobenzeno

    Directory of Open Access Journals (Sweden)

    Fukushima Romualdo Shigueo

    2003-01-01

    Full Text Available A correta quantificação da concentração de lignina em plantas forrageiras, pelo método espectrofotométrico, pressupõe a existência de um padrão de referência. Um padrão de referência deve ter composição fenólica semelhante à da lignina da parede celular. O objetivo deste trabalho foi verificar se ligninas extraídas com solução ácida de dioxano para serem utilizadas como padrão de referência, apresentariam variação na composição fenólica da mesma maneira que a lignina da parede celular. Amostras de parede celular de "bromegrass", milho e trevo-vermelho foram submetidas ao método para extração de ligninas com solução ácida de dioxano. A composição fenólica das ligninas foi analisada mediante oxidação alcalina pelo nitrobenzeno com posterior separação dos componentes monoméricos via HPLC. As ligninas extraídas confirmaram a existência de variação na composição fenólica da mesma maneira às ligninas intactas presentes na parede celular e de substancial presença de ácidos cinâmicos nas ligninas de gramíneas. No que diz respeito à composição fenólica, ligninas extraídas com solução ácida de dioxano podem ser consideradas potenciais padrões de referência paras as análises espectrofotométricas.

  16. Fe-N co-doped SiO2@TiO2 yolk-shell hollow nanospheres with enhanced visible light photocatalytic degradation

    Science.gov (United States)

    Wan, Hengcheng; Yao, Weitang; Zhu, Wenkun; Tang, Yi; Ge, Huilin; Shi, Xiaozhong; Duan, Tao

    2018-06-01

    SiO2@TiO2 yolk@shell hollow nanospheres (STNSs) is considered as an outstanding photocatalyst due to its tunable structure and composition. Based on this point, we present an unprecedentedly excellent photocatalytic property of STNSs toward tannic acid via a Fe-N co-doped strategy. Their morphologies, compositions, structure and properties are characterized. The Fe-N co-doped STNSs formed good hollow yolk@shell structure. The results show that the energy gap of the composites can be downgraded to 2.82 eV (pure TiO2 = 3.2 eV). Photocatalytic degradation of tannic acid (TA, 30 mg L-1) under visible light (380 nm TiO2 nanospheres, non-doped STNSs and N-doped STNSs, the Fe-N co-doped STNSs exhibits the highest activity, which can degrade 99.5% TA into CO2 and H2O in 80 min. The probable degradation mechanism of the composites is simultaneously proposed, the band gap of STNSs becomes narrow by co-doping Fe-N, so that the TiO2 shell can stimulate electrons under visible light exposure, generate the ions of radOH and radO2- with a strong oxidizing property. Therefore this approach works is much desired for radioactive organic wastewater photocatalytic degradation.

  17. Dendrochronology of bristlecone pine, Pinus longaeva

    International Nuclear Information System (INIS)

    Ferguson, C.W.

    1979-01-01

    Since 1953 the Laboratory of Tree-Ring Research has conducted dendrochronological studies of bristlecone pine Pinus longaeva D.K. Bailey, sp. nov.) in the White Mountains of California. This research resulted in the establishment of a continuous tree-ring sequence of 8253 yr. The millennia-old pines have emerged as a unique source of chronological data and the precisely dated wood is essential to certain paleoenvironmental and geophysical investigations. Over 1000 dendrochronologically dated decade samples of bristlecone pine supplied to three C-14 laboratories have been used to calibrate the radiocarbon time scale for the past seven millennia, a development of far reaching consequences in the fields of archaeology and geology. In addition, recent advances in other methods of analyzing past climatic variability - techniques involving stable isotope ratios, amino acid racemization, remanent magnetism and trace element abundances - have greatly increased the demand for wood of known age and, hence, for chronology development. Spanning the past 7500 yr, 1138 prepared decade samples, with a total weight of nearly 16 kg are available for study. (author)

  18. Effects of introgression on the genetic population structure of two ecologically and economically important conifer species: lodgepole pine (Pinus contorta var. latifolia) and jack pine (Pinus banksiana).

    Science.gov (United States)

    Cullingham, Catherine I; Cooke, Janice E K; Coltman, David W

    2013-10-01

    Forest trees exhibit a remarkable range of adaptations to their environment, but as a result of frequent and long-distance gene flow, populations are often only weakly differentiated. Lodgepole and jack pine hybridize in western Canada, which adds the opportunity for introgression through hybridization to contribute to population structure and (or) adaptive variation. Access to large sample size, high density SNP datasets for these species would improve our ability to resolve population structure, parameterize introgression, and separate the influence of demography from adaptation. To accomplish this, 454 transcriptome reads for lodgepole and jack pine were assembled using Newbler and MIRA, the assemblies mined for SNPs, and 1536 SNPs were selected for typing on lodgepole pine, jack pine, and their hybrids (N = 536). We identified population structure using both Bayesian clustering and discriminate analysis of principle components. Introgressed SNP loci were identified and their influence on observed population structure was assessed. We found that introgressed loci resulted in increased differentiation both within lodgepole and jack pine populations. These findings are timely given the recent mountain pine beetle population expansion in the hybrid zone, and will facilitate future studies of adaptive traits in these ecologically important species.

  19. Watershed-Induced Limnological and Microbial Status in Two Oligotrophic Andean Lakes Exposed to the Same Climatic Scenario

    Directory of Open Access Journals (Sweden)

    Alex Echeverría-Vega

    2018-03-01

    Full Text Available Laguna Negra and Lo Encañado are two oligotrophic Andean lakes forming part of the system fed by meltwater from distinct glacial tongues of the Echaurren glacier in central Chile, which is in a recession period. The recent increase in temperature and decline in precipitation have led to an increase of glacial meltwater and sediments entering these lakes. Although the lacustrine systems are also hydrogeologically connected, the limnology of the lakes is strongly controlled by the surface processes related to the respective sub-watersheds and hydrology. Watershed characteristics (area and length, slope, lithology, resistance to erosion, among others affect the chemical and physical characteristics of both lakes (e.g., nutrient concentration and turbidity. We studied physical and chemical variables and performed 16S rRNA amplicon sequencing to determine the specific microbial signature of the lakes. The transparency, temperature, turbidity and concentrations of chlorophyll-a, dissolved organic matter, nutrients and the total number of cells, revealed the different status of both lakes at the time of sampling. The predominant bacterial groups in both lakes were Proteobacteria, Verrucomicrobia, and Bacteroidetes. Interestingly, the contribution of phototrophs was significantly higher in LN compared to LE (13 and 4% respectively and the major fraction corresponded to Anoxygenic Phototrophs (AP represented by Chloroflexi, Alpha, and Betaproteobacteria. Multivariate analyses showed that the nutrient levels and the light availability of both lakes, which finally depend on the hydrological characteristics of the respective watersheds, explain the differential community composition/function. The abundance of a diverse photoheterotrophic bacterioplankton community suggests that the ability to utilize solar energy along with organic and inorganic substrates is a key function in these oligotrophic mountain lakes.

  20. Watershed-Induced Limnological and Microbial Status in Two Oligotrophic Andean Lakes Exposed to the Same Climatic Scenario.

    Science.gov (United States)

    Echeverría-Vega, Alex; Chong, Guillermo; Serrano, Antonio E; Guajardo, Mariela; Encalada, Olga; Parro, Victor; Blanco, Yolanda; Rivas, Luis; Rose, Kevin C; Moreno-Paz, Mercedes; Luque, José A; Cabrol, Nathalie A; Demergasso, Cecilia S

    2018-01-01

    Laguna Negra and Lo Encañado are two oligotrophic Andean lakes forming part of the system fed by meltwater from distinct glacial tongues of the Echaurren glacier in central Chile, which is in a recession period. The recent increase in temperature and decline in precipitation have led to an increase of glacial meltwater and sediments entering these lakes. Although the lacustrine systems are also hydrogeologically connected, the limnology of the lakes is strongly controlled by the surface processes related to the respective sub-watersheds and hydrology. Watershed characteristics (area and length, slope, lithology, resistance to erosion, among others) affect the chemical and physical characteristics of both lakes (e.g., nutrient concentration and turbidity). We studied physical and chemical variables and performed 16S rRNA amplicon sequencing to determine the specific microbial signature of the lakes. The transparency, temperature, turbidity and concentrations of chlorophyll-a, dissolved organic matter, nutrients and the total number of cells, revealed the different status of both lakes at the time of sampling. The predominant bacterial groups in both lakes were Proteobacteria, Verrucomicrobia, and Bacteroidetes. Interestingly, the contribution of phototrophs was significantly higher in LN compared to LE (13 and 4% respectively) and the major fraction corresponded to Anoxygenic Phototrophs (AP) represented by Chloroflexi, Alpha, and Betaproteobacteria. Multivariate analyses showed that the nutrient levels and the light availability of both lakes, which finally depend on the hydrological characteristics of the respective watersheds, explain the differential community composition/function. The abundance of a diverse photoheterotrophic bacterioplankton community suggests that the ability to utilize solar energy along with organic and inorganic substrates is a key function in these oligotrophic mountain lakes.

  1. Watershed-Induced Limnological and Microbial Status in Two Oligotrophic Andean Lakes Exposed to the Same Climatic Scenario

    Science.gov (United States)

    Echeverría-Vega, Alex; Chong, Guillermo; Serrano, Antonio E.; Guajardo, Mariela; Encalada, Olga; Parro, Victor; Blanco, Yolanda; Rivas, Luis; Rose, Kevin C.; Moreno-Paz, Mercedes; Luque, José A.; Cabrol, Nathalie A.; Demergasso, Cecilia S.

    2018-01-01

    Laguna Negra and Lo Encañado are two oligotrophic Andean lakes forming part of the system fed by meltwater from distinct glacial tongues of the Echaurren glacier in central Chile, which is in a recession period. The recent increase in temperature and decline in precipitation have led to an increase of glacial meltwater and sediments entering these lakes. Although the lacustrine systems are also hydrogeologically connected, the limnology of the lakes is strongly controlled by the surface processes related to the respective sub-watersheds and hydrology. Watershed characteristics (area and length, slope, lithology, resistance to erosion, among others) affect the chemical and physical characteristics of both lakes (e.g., nutrient concentration and turbidity). We studied physical and chemical variables and performed 16S rRNA amplicon sequencing to determine the specific microbial signature of the lakes. The transparency, temperature, turbidity and concentrations of chlorophyll-a, dissolved organic matter, nutrients and the total number of cells, revealed the different status of both lakes at the time of sampling. The predominant bacterial groups in both lakes were Proteobacteria, Verrucomicrobia, and Bacteroidetes. Interestingly, the contribution of phototrophs was significantly higher in LN compared to LE (13 and 4% respectively) and the major fraction corresponded to Anoxygenic Phototrophs (AP) represented by Chloroflexi, Alpha, and Betaproteobacteria. Multivariate analyses showed that the nutrient levels and the light availability of both lakes, which finally depend on the hydrological characteristics of the respective watersheds, explain the differential community composition/function. The abundance of a diverse photoheterotrophic bacterioplankton community suggests that the ability to utilize solar energy along with organic and inorganic substrates is a key function in these oligotrophic mountain lakes. PMID:29556224

  2. Using fire to restore pine/hardwood ecosystems in the Southern Appalachians of North Carolina

    Science.gov (United States)

    James M. Vose; Wayne T. Swank; Barton D. Clinton; Ronald L. Hendrick; Amy E. Major

    1997-01-01

    In the Southern Appalachians, mixed pine/hardwood ecosystems occupy the most xeric sites (i.e., south/west aspect ridge sites). They are typically comprised of varying proportions of pitch pine (Pinus rigida), Virginia pine (Pinus virginiana), and/or shortleaf pine (Pinus echinata) and a mixture of hardwoods, including scarlet oak (Quercus coccinea), chestnut oak (...

  3. Interacting effects of sulphate pollution, sulphide toxicity and eutrophication on vegetation development in fens: A mesocosm experiment

    Energy Technology Data Exchange (ETDEWEB)

    Geurts, Jeroen J.M., E-mail: j.geurts@b-ware.e [Aquatic Ecology and Environmental Biology, Institute for Wetland and Water Research, Radboud University Nijmegen, Toernooiveld 1, 6525 ED Nijmegen (Netherlands); B-WARE Research Centre, Radboud University Nijmegen, Toernooiveld 1, 6525 ED Nijmegen (Netherlands); Sarneel, Judith M. [Landscape Ecology, Institute of Environmental Biology, Utrecht University, Sorbonnelaan 16, 3584 CA Utrecht (Netherlands); Willers, Bart J.C.; Roelofs, Jan G.M. [Aquatic Ecology and Environmental Biology, Institute for Wetland and Water Research, Radboud University Nijmegen, Toernooiveld 1, 6525 ED Nijmegen (Netherlands); Verhoeven, Jos T.A. [Landscape Ecology, Institute of Environmental Biology, Utrecht University, Sorbonnelaan 16, 3584 CA Utrecht (Netherlands); Lamers, Leon P.M. [Aquatic Ecology and Environmental Biology, Institute for Wetland and Water Research, Radboud University Nijmegen, Toernooiveld 1, 6525 ED Nijmegen (Netherlands)

    2009-07-15

    Both eutrophication and SO{sub 4} pollution can lead to higher availability of nutrients and potentially toxic compounds in wetlands. To unravel the interaction between the level of eutrophication and toxicity at species and community level, effects of SO{sub 4} were tested in nutrient-poor and nutrient-rich fen mesocosms. Biomass production of aquatic and semi-aquatic macrophytes and colonization of the water layer increased after fertilization, leading to dominance of highly competitive species. SO{sub 4} addition increased alkalinity and sulphide concentrations, leading to decomposition and additional eutrophication. SO{sub 4} pollution and concomitant sulphide production considerably reduced biomass production and colonization, but macrophytes were less vulnerable in fertilized conditions. The experiment shows that competition between species, vegetation succession and terrestrialization are not only influenced by nutrient availability, but also by toxicity, which strongly interacts with the level of eutrophication. This implies that previously neutralized toxicity effects in eutrophied fens may appear after nutrient reduction measures have been taken. - Interspecific competition, vegetation succession and terrestrialization in fens depend on the interacting effects of SO{sub 4} pollution, sulphide toxicity and nutrient availability.

  4. Potential for hydrogen-oxidizing chemolithoautotrophic and diazotrophic populations to initiate biofilm formation in oligotrophic, deep terrestrial subsurface waters.

    Science.gov (United States)

    Wu, Xiaofen; Pedersen, Karsten; Edlund, Johanna; Eriksson, Lena; Åström, Mats; Andersson, Anders F; Bertilsson, Stefan; Dopson, Mark

    2017-03-23

    Deep terrestrial biosphere waters are separated from the light-driven surface by the time required to percolate to the subsurface. Despite biofilms being the dominant form of microbial life in many natural environments, they have received little attention in the oligotrophic and anaerobic waters found in deep bedrock fractures. This study is the first to use community DNA sequencing to describe biofilm formation under in situ conditions in the deep terrestrial biosphere. In this study, flow cells were attached to boreholes containing either "modern marine" or "old saline" waters of different origin and degree of isolation from the light-driven surface of the earth. Using 16S rRNA gene sequencing, we showed that planktonic and attached populations were dissimilar while gene frequencies in the metagenomes suggested that hydrogen-fed, carbon dioxide- and nitrogen-fixing populations were responsible for biofilm formation across the two aquifers. Metagenome analyses further suggested that only a subset of the populations were able to attach and produce an extracellular polysaccharide matrix. Initial biofilm formation is thus likely to be mediated by a few bacterial populations which were similar to Epsilonproteobacteria, Deltaproteobacteria, Betaproteobacteria, Verrucomicrobia, and unclassified bacteria. Populations potentially capable of attaching to a surface and to produce extracellular polysaccharide matrix for attachment were identified in the terrestrial deep biosphere. Our results suggest that the biofilm populations were taxonomically distinct from the planktonic community and were enriched in populations with a chemolithoautotrophic and diazotrophic metabolism coupling hydrogen oxidation to energy conservation under oligotrophic conditions.

  5. a fenómenos epidemiológicos

    Directory of Open Access Journals (Sweden)

    Carlos Arturo Castro Castro

    2005-01-01

    Full Text Available En este artículo se presentan avances del proyecto de investigación modelación y simulación computacional usando sistemas de información geográfica (SIG con dinámicas de sistemas aplicados a fenómenos epidemiológicos con el cual se han abordado los principales modelos matemáticos usados en epidemiología (susceptible- infectado-recuperado: SIR, susceptible-infectado-recuperado-susceptible: SIRS, susceptible-infectado-susceptible: SIS, para su integración, espacialización y simulación usando diferentes técnicas computacionales con el fin de modelar factores críticos en la propagación de epidemias. Para correr el modelo, se tomaron los datos de una epidemia de asma en el distrito de Manhattan de Nueva York, del tutotial de ARCGIS® versión 8.3.

  6. A biologically-based individual tree model for managing the longleaf pine ecosystem

    Science.gov (United States)

    Rick Smith; Greg Somers

    1998-01-01

    Duration: 1995-present Objective: Develop a longleaf pine dynamics model and simulation system to define desirable ecosystem management practices in existing and future longleaf pine stands. Methods: Naturally-regenerated longleaf pine trees are being destructively sampled to measure their recent growth and dynamics. Soils and climate data will be combined with the...

  7. Dynamics of biochemical processes and redox conditions in geochemically linked landscapes of oligotrophic bogs

    Science.gov (United States)

    Inisheva, L. I.; Szajdak, L.; Sergeeva, M. A.

    2016-04-01

    The biological activity in oligotrophic peatlands at the margins of the Vasyugan Mire has been studied. It is shown found that differently directed biochemical processes manifest themselves in the entire peat profile down to the underlying mineral substrate. Their activity is highly variable. It is argued that the notion about active and inert layers in peat soils is only applicable for the description of their water regime. The degree of the biochemical activity is specified by the physical soil properties. As a result of the biochemical processes, a micromosaic aerobic-anaerobic medium is developed under the surface waterlogged layer of peat deposits. This layer contains the gas phase, including oxygen. It is concluded that the organic and mineral parts of peat bogs represent a single functional system of a genetic peat profile with a clear record of the history of its development.

  8. Pine snake (Pituophis ruthveni and Pituophis mellanoleucus lodingi) hibernacula

    Science.gov (United States)

    D.C. Rudolph; R.R. Schaefer; S.J. Burgdorf; M. Duran; R.N. Conner

    2007-01-01

    Snakes are often highly selective in the choice of sites for hibernation, and suitable sites can potentially be a limiting resource. Hibernating Louisiana Pine Snakes (Pituopllis ruthveni; N = 7) in eastern Texas and Black Pine Snakes (Pituophis melanoleucus lodingi; N = 5) in Mississippi were excavated to characterize their...

  9. Water flow and solute transport in floating fen root mats

    Science.gov (United States)

    Stofberg, Sija F.; EATM van der Zee, Sjoerd

    2015-04-01

    Floating fens are valuable wetlands, found in North-Western Europe, that are formed by floating root mats when old turf ponds are colonized by plants. These terrestrialization ecosystems are known for their biodiversity and the presence of rare plant species, and the root mats reveal different vegetation zones at a small scale. The vegetation zones are a result of strong gradients in abiotic conditions, including groundwater dynamics, nutrients and pH. To prevent irreversible drought effects such as land subsidence and mineralization of peat, water management involves import of water from elsewhere to maintain constant surface water levels. Imported water may have elevated levels of salinity during dry summers, and salt exposure may threaten the vegetation. To assess the risk of exposure of the rare plant species to salinity, the hydrology of such root mats must be understood. Physical properties of root mats have scarcely been investigated. We have measured soil characteristics, hydraulic conductivity, vertical root mat movement and groundwater dynamics in a floating root mat in the nature reserve Nieuwkoopse Plassen, in the Netherlands. The root mat mostly consists of roots and organic material, in which the soil has a high saturated water content, and strongly varies in its stage of decomposition. We have found a distinct negative correlation between degree of decomposition and hydraulic conductivity, similar to observations for bogs in the literature. Our results show that the relatively young, thin edge of the root mat that colonizes the surface water has a high hydraulic conductivity and floats in the surface water, resulting in very small groundwater fluctuations within the root mat. The older part of the root mat, that is connected to the deeper peat layers is hydrologically more isolated and the material has a lower conductivity. Here, the groundwater fluctuates strongly with atmospheric forcing. The zones of hydraulic properties and vegetation, appear to

  10. Host selection by the pine processionary moth enhances larval performance: An experiment

    Science.gov (United States)

    Pérez-Contreras, Tomás; Soler, Juan J.; Soler, Manuel

    2014-02-01

    The development of a phytophagous insect depends on the nutritional characteristics of plants on which it feeds. Offspring from different females, however, may vary in their ability to develop in different host species and therefore females should place their eggs on host plants that result in the highest performance for the insect offspring. Causes underlying the predicted relationships between host selection and offspring performance may be: (1) a genetic association between larval ability to exploit particular hosts and the female insect's host preference; and (2) phenotypic plasticity of larvae that may be due to (a) maternal effects (e.g. differential investment in eggs) or (b) diet. In this work, we analyse the performance (i.e. hatching success and larval size and mortality) of the pine processionary (Thaumetopoea pityocampa) caterpillar developing in Aleppo (Pinus halepensis) or maritime (Pinus pinaster) pines. Larvae of this moth species do not move from the individual pine selected by the mother for oviposition. By means of cross-fostering experiments of eggs batches and silk nests of larvae between these two pine species, we explored whether phenotypic plasticity of offspring traits or genetic correlations between mother and offspring traits account for variation in developmental characteristics of caterpillars. Our results showed that females preferentially selected Aleppo pine for oviposition. Moreover, the offspring had the highest probability of survival and reached a larger body size in this pine species independently of whether or not batches were experimentally cross-fostered. Notably, the interaction between identity of donor and receiver pine species of larvae nests explained a significant proportion of variance of larval size and mortality, suggesting a role of diet-induced phenotypic plasticity of the hatchlings. These results suggest that both female selection of the more appropriate pine species and phenotypic plasticity of larva explain the

  11. Microsatellite DNA in genomic survey sequences and UniGenes of loblolly pine

    Science.gov (United States)

    Craig S Echt; Surya Saha; Dennis L Deemer; C Dana Nelson

    2011-01-01

    Genomic DNA sequence databases are a potential and growing resource for simple sequence repeat (SSR) marker development in loblolly pine (Pinus taeda L.). Loblolly pine also has many expressed sequence tags (ESTs) available for microsatellite (SSR) marker development. We compared loblolly pine SSR densities in genome survey sequences (GSSs) to those in non-redundant...

  12. Fenómenos que Organizan el Límite (Phenomena that Organize Limits

    Directory of Open Access Journals (Sweden)

    María Teresa Sánchez

    2007-03-01

    Full Text Available En este artículo se pone de manifiesto la presencia de los fenómenos de aproximación organizados por una definición de límite en el caso de las sucesiones de números reales y de las funciones reales de una variable real. La exposición incluye la caracterización de tales fenómenos, una descripción del análisis comparativo desarrollado en base a ellos entre dos definiciones formales de límite de sucesión y función, y una síntesis del estudio llevado a cabo sobre una muestra intencional de libros de texto de matemáticas.In this paper we show the presence of the phenomena of approximation organized by a definition of limit in the cases of the successions of real numbers and the real functions of one real variable. The exposition includes the characterization of such phenomena, a description of the comparative analysis, developed using them, between two formal definitions of limit of succession and function, and a synthesis of the study carried out on an intentional sample of mathematics textbooks.

  13. Invasive pathogen threatens bird-pine mutualism: implications for sustaining a high-elevation ecosystem.

    Science.gov (United States)

    McKinney, Shawn T; Fiedler, Carl E; Tomback, Diana F

    2009-04-01

    Human-caused disruptions to seed-dispersal mutualisms increase the extinction risk for both plant and animal species. Large-seeded plants can be particularly vulnerable due to highly specialized dispersal systems and no compensatory regeneration mechanisms. Whitebark pine (Pinus albicaulis), a keystone subalpine species, obligately depends upon the Clark's Nutcracker (Nucifraga columbiana) for dispersal of its large, wingless seeds. Clark's Nutcracker, a facultative mutualist with whitebark pine, is sensitive to rates of energy gain, and emigrates from subalpine forests during periods of cone shortages. The invasive fungal pathogen Cronartium ribicola, which causes white pine blister rust, reduces whitebark pine cone production by killing cone-bearing branches and trees. Mortality from blister rust reaches 90% or higher in some whitebark pine forests in the Northern Rocky Mountains, USA, and the rust now occurs nearly rangewide in whitebark pine. Our objectives were to identify the minimum level of cone production necessary to elicit seed dispersal by nutcrackers and to determine how cone production is influenced by forest structure and health. We quantified forest conditions and ecological interactions between nutcrackers and whitebark pine in three Rocky Mountain ecosystems that differ in levels of rust infection and mortality. Both the frequency of nutcracker occurrence and probability of seed dispersal were strongly related to annual whitebark pine cone production, which had a positive linear association with live whitebark pine basal area, and negative linear association with whitebark pine tree mortality and rust infection. From our data, we estimated that a threshold level of approximately 1000 cones/ha is needed for a high likelihood of seed dispersal by nutcrackers (probability > or = 0.7), and that this level of cone production can be met by forests with live whitebark pine basal area > 5.0 m2/ha. The risk of mutualism disruption is greatest in northern

  14. The DNA Repair Repertoire of Mycobacterium smegmatis FenA Includes the Incision of DNA 5' Flaps and the Removal of 5' Adenylylated Products of Aborted Nick Ligation.

    Science.gov (United States)

    Uson, Maria Loressa; Ghosh, Shreya; Shuman, Stewart

    2017-09-01

    We characterize Mycobacterium smegmatis FenA as a manganese-dependent 5'-flap endonuclease homologous to the 5'-exonuclease of DNA polymerase I. FenA incises a nicked 5' flap between the first and second nucleotides of the duplex segment to yield a 1-nucleotide gapped DNA, which is then further resected in dinucleotide steps. Initial FenA cleavage at a Y-flap or nick occurs between the first and second nucleotides of the duplex. However, when the template 3' single strand is eliminated to create a 5'-tailed duplex, FenA incision shifts to between the second and third nucleotides. A double-flap substrate with a mobile junction (mimicking limited strand displacement synthesis during gap repair) is preferentially incised as the 1-nucleotide 3'-flap isomer, with the scissile phosphodiester shifted by one nucleotide versus a static double flap. FenA efficiently removes the 5' App(dN) terminus of an aborted nick ligation reaction intermediate, thereby highlighting FenA as an agent of repair of such lesions, which are formed under a variety of circumstances by bacterial NAD + -dependent DNA ligases and especially by mycobacterial DNA ligases D and C. IMPORTANCE Structure-specific DNA endonucleases are implicated in bacterial DNA replication, repair, and recombination, yet there is scant knowledge of the roster and catalytic repertoire of such nucleases in Mycobacteria This study identifies M. smegmatis FenA as a stand-alone endonuclease homologous to the 5'-exonuclease domain of mycobacterial DNA polymerase 1. FenA incises 5' flaps, 5' nicks, and 5' App(dN) intermediates of aborted nick ligation. The isolated N-terminal domain of M. smegmatis Pol1 is also shown to be a flap endonuclease. Copyright © 2017 American Society for Microbiology.

  15. Weevil - red rot associations in eastern white pine

    Science.gov (United States)

    Myron D. Ostrander; Clifford H. Foster

    1957-01-01

    The presence of red rot (Fomes pini) in pruned white pine stands has often been attributed to the act of pruning. This assumption may well be true for heavily stocked stands where thinning has been neglected and pruning scars are slow to heal. The question then arises: How do we account for the red rot often found in vigorous unpruned white pine stands? Evidence...

  16. Cold-Active, Heterotrophic Bacteria from the Highly Oligotrophic Waters of Lake Vanda, Antarctica

    Directory of Open Access Journals (Sweden)

    Nicole A. Vander Schaaf

    2015-07-01

    Full Text Available The permanently ice-covered lakes of the McMurdo Dry Valleys, Antarctica are distinctive ecosystems that consist strictly of microbial communities. In this study, water samples were collected from Lake Vanda, a stratified Dry Valley lake whose upper waters (from just below the ice cover to nearly 60 m are highly oligotrophic, and used to establish enrichment cultures. Six strains of psychrotolerant, heterotrophic bacteria were isolated from lake water samples from a depth of 50 or 55 m. Phylogenetic analyses showed the Lake Vanda strains to be species of Nocardiaceae, Caulobacteraceae, Sphingomonadaceae, and Bradyrhizobiaceae. All Lake Vanda strains grew at temperatures near or below 0 °C, but optimal growth occurred from 18 to 24 °C. Some strains showed significant halotolerance, but no strains required NaCl for growth. The isolates described herein include cold-active species not previously reported from Dry Valley lakes, and their physiological and phylogenetic characterization broadens our understanding of these limnologically unique lakes.

  17. Edible species of the fungal genus hebeloma and two neotropical pines

    International Nuclear Information System (INIS)

    Hernandez, V.C.; Moreno, J.P.; Lizaola, R.Q.; Moreno, J.P.

    2015-01-01

    Mexico has one of the largest diversities of pines and ectomycorrhizal fungi known world-wide. Therefore, describingnative ectomycorrizal species from the country associated with pines is important because of their biotechnological potential in the forestry and food sectors. Worldwide, Hebeloma has generally been considered a genus of poisonous ectomycorrhizal fungi. However, interestingly, in central Mexico there is a complex of under-studied Hebeloma species which are used as food in large quantities and have a great economic and social importance. Three edible species of Hebeloma widely marketed in the country were identified: Hebeloma alpinum, H. mesophaeum and H. leucosarx with scanning electron microscopy on the basis of different ornamentation patterns in the spores of these species. Synthesis was carried out by inoculating two Neotropical pines with sporomes of the three described Hebeloma species. To achieve this, inoculated pines were kept in greenhouse conditions during one year. A characteristic morphotype for each fungal species was observed and it is described here. The first known description of the morphotype of Hebeloma alpinum with pines is presented. This seminal work gives a tool to identify the morphotypes produced by the main edible ectomycorrhizal species of Hebeloma marketed in Mexico, with biotechnological potential to inoculate pines used in reforestation programmes in Neotropical areas. (author)

  18. An economic assessment of mountain pine beetle timber salvage in the west

    Science.gov (United States)

    Jeffrey P. Prestemon; Karen L. Abt; Kevin M. Potter; Frank H. Koch

    2013-01-01

    The mountain pine beetle has killed lodgepole pine and other species of pines in the western United States in an ongoing epidemic. The most heavily affected states are in the interior West: Colorado, Idaho, Montana, and Wyoming, with smaller losses elsewhere. Timber salvage is one response to the epidemic, which could generate revenues for affected landowners and...

  19. A revised managers handbook for red pine in the North Central Region

    Science.gov (United States)

    Daniel W. Gilmore; Brian J. Palik

    2006-01-01

    This new version of the Red Pine Managers Guide gathers up-to-date information from many disciplines to address a wide range of red pine management issues. It provides guidance on managing red pine on extended rotations with a focus on landscape-scale objectives along with the traditional forest management tools focusing on production silviculture. The insect and...

  20. Xylem monoterpenes of some hard pines of Western North America: three studies

    Science.gov (United States)

    Richard H. Smith

    1982-01-01

    Monoterpene composition was studied in a number of hard pine species and results were compared with earlier work. (1) Intratree measurements showed strong constancy of composition in both single-stemmed and forked trees of ponderosa, Jeffrey, Coulter, and Jeffrey x ponderosa pines. In grafts of these and other pines, the scion influenced the root stock, but not the...

  1. Research of Ancient Architectures in Jin-Fen Area Based on GIS&BIM Technology

    Science.gov (United States)

    Jia, Jing; Zheng, Qiuhong; Gao, Huiying; Sun, Hai

    2017-05-01

    The number of well-preserved ancient buildings located in Shanxi Province, enjoying the absolute maximum proportion of ancient architectures in China, is about 18418, among which, 9053 buildings have the structural style of wood frame. The value of the application of BIM (Building Information Modeling) and GIS (Geographic Information System) is gradually probed and testified in the corresponding fields of ancient architecture’s spatial distribution information management, routine maintenance and special conservation & restoration, the evaluation and simulation of related disasters, such as earthquake. The research objects are ancient architectures in JIN-FEN area, which were first investigated by Sicheng LIANG and recorded in his work of “Chinese ancient architectures survey report”. The research objects, i.e. the ancient architectures in Jin-Fen area include those in Sicheng LIANG’s investigation, and further adjustments were made through authors’ on-site investigation and literature searching & collection. During this research process, the spatial distributing Geodatabase of research objects is established utilizing GIS. The BIM components library for ancient buildings is formed combining on-site investigation data and precedent classic works, such as “Yingzao Fashi”, a treatise on architectural methods in Song Dynasty, “Yongle Encyclopedia” and “Gongcheng Zuofa Zeli”, case collections of engineering practice, by the Ministry of Construction of Qing Dynasty. A building of Guangsheng temple in Hongtong county is selected as an example to elaborate the BIM model construction process based on the BIM components library for ancient buildings. Based on the foregoing work results of spatial distribution data, attribute data of features, 3D graphic information and parametric building information model, the information management system for ancient architectures in Jin-Fen Area, utilizing GIS&BIM technology, could be constructed to support the

  2. Effects of a Severe Mountain Pine Beetle Epidemic in Western Alberta, Canada under Two Forest Management Scenarios

    Directory of Open Access Journals (Sweden)

    Richard R. Schneider

    2010-01-01

    Full Text Available We used a simulation model to investigate possible effects of a severe mountain pine beetle (Dendroctonus ponderosae Hopkins epidemic under two management scenarios in Alberta, Canada. Our simulated outbreak was based on the current epidemic in British Columbia, which may kill close to 80% of the province's pine volume. Our two management scenarios were conventional harvest and a pine-reduction strategy modeled on a component of Alberta's Mountain Pine Beetle Management Strategy. The pine strategy seeks to reduce the number of susceptible pine stands by 75% over the next 20 years through targeted harvesting by the forest industry. Our simulations showed that the pine strategy could not be effectively implemented, even if the onset of the beetle outbreak was delayed for 20 years. Even though we increased mill capacity by 20% and directed all harvesting to high volume pine stands during the pine strategy's surge cut, the amount of highly susceptible pine was reduced by only 43%. Additional pine volume remained within mixed stands that were not targeted by the pine strategy. When the outbreak occurred in each scenario, sufficient pine remained on the landscape for the beetle to cause the timber supply to collapse. Alternative management approaches and avenues for future research are discussed.

  3. Environmental and Physiographic Controls on Inter-Growing Season Variability of Carbon Dioxide and Water Vapour Fluxes in a Minerotrophic Fen

    Science.gov (United States)

    van der Kamp, G.; Sonnentag, O.; Chen, J. M.; Barr, A.; Hedstrom, N.; Granger, R.

    2008-12-01

    The interaction of fens with groundwater is spatially and temporally highly variable in response to meteorological conditions, resulting in frequent changes of groundwater fluxes in both vertical and lateral directions (flow reversals) across the mineral soil-peat boundary. However, despite the importance of the topographic and hydrogeological setting of fens, no study has been reported in the literature that explores a fen's atmospheric CO2 and energy flux densities under contrasting meteorological conditions in response to its physiographic setting. In our contribution we report four years of growing season eddy covariance and supporting measurements from the Canada Fluxnet-BERMS fen (formerly BOREAS southern peatland) in Saskatchewan, Canada. We first analyze hydrological data along two piezometer transects across the mineral soil-peat boundary with the objective of assessing changes in water table configuration and thus hydraulic gradients, indicating flow reversals, in response to dry and wet meteorological conditions. Next we quantify and compare growing season totals and diurnal and daily variations in evapotranspiration (ET) and net ecosystem exchange (NEE) and its component fluxes gross ecosystem productivity (GPP) and terrestrial ecosystem respiration (TER) to identify their controls with a major focus on water table depth. While ET growing season totals were similar (~ 310 mm) under dry and wet meteorological conditions, the CO2 sink- source strength of Sandhill fen varied substantially from carbon neutral (NEE = -2 [+-7] g C m-2 per growing season) under dry meteorological condition (2003) to a moderate CO2- sink with NEE ranging between 157 [+- 10] and 190 [+- 11] g C m-2 per growing season under wet meteorological conditions (2004, 2005, and 2006). Using a process-oriented ecosystem model, BEPS-TerrainLab, we investigate how different canopy components at Sandhill contribute to total ET and GPP, and thus water use efficiency, under dry and wet

  4. Violência como fenômeno intrínseco à cultura política brasileira

    Directory of Open Access Journals (Sweden)

    Antonio M. Soares

    2016-06-01

    Full Text Available Este artigo problematiza o conceito de violência e suas mutações através dos tempos. Como fenômeno cultural, a violência é construída na sociedade e se processa de forma a romper com os próprios códigos de ordens produzidos por ela. No caso do Brasil a violência se mostra intrínseca ao processo de formação da sociedade brasileira, estando presente nas lógicas autoritárias e na imposição cultural desde os tempos da colonização. A violência emerge como uma agressão ao indivíduo e ao coletivo, ela aniquila o sentido da política e desabilita o mundo comum. As interpretações presentes neste trabalho buscam aprofundar as análises sobre a violência enquanto fenômeno social e cultural, redimensionando os efeitos que ela produz para a condição humana e suas associações com as dimensões da civilidade, incivilidade e descivilidade. Neste contexto, destacaremos como o fenômeno da violência se afirmou como uma dimensão estrutural e cultural da formação da sociedade brasileira, como ele se revela na contemporaneidade, nos jogos de poder, nas relações de força e no movimento de fronteiras tênues entre o legal e o ilegal.

  5. Análisis de la influencia del fenómeno del ciberterrorismo en las dinámicas de seguridad de la Unión Europea

    OpenAIRE

    Torres Pedraza, Julián Alejandro

    2014-01-01

    El fenómeno del ciberterrorismo se constituye como una nueva amenaza a la seguridad internacional, este fenómeno es el resultado de distintos procesos en el sistema internacional como el de la globalización. La definición del concepto se establece por la convergencia entre el ciberespacio y el terrorismo. El objetivo de esta investigación es explicar las distintas dimensiones del ciberterrorismo, métodos de ataque, acciones pasadas, propósito del fenómeno, situación actual y vulnerabilidades....

  6. The mountain pine beetle and whitebark pine waltz: Has the music changed?

    Science.gov (United States)

    Barbara J. Bentz; Greta Schen-Langenheim

    2007-01-01

    The mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae, Scolytinae) (MPB), is a bark beetle native to western North American forests, spanning wide latitudinal and elevational gradients. MPB infest and reproduce within the phloem of most Pinus species from northern Baja California in Mexico to central British Columbia in...

  7. Using Black Light to Find Jack-Pine Budworm Egg Masses

    Science.gov (United States)

    Daniel T. Jennings

    1968-01-01

    Jack pine foliage infested with jack-pine budworm egg masses was examined under two kinds of light -- black light and a combination of natural and fluorescent light. Black light significantly increased the accuracy of count but not the efficiency of examination.

  8. How to Identify and Manage Pine Wilt Disease and Treat Wood Products Infested by the Pinewood Nematodes

    Science.gov (United States)

    Jim Hanson; Michelle Cram

    2004-01-01

    Pine wilt is a disease of pine (Pinus spp.) caused by the pinewood nematode, Bursaphelenchus xylophilus. The pinewood nematode is native to North America and is not considered a primary pathogen of native pines, but is the cause of pine wilt in some non-native pines. In countries where the pinewood nematode has been introduced, such as Japan and China, pine wilt is an...

  9. [Dendrochronology of Chinese pine in Mulan-Weichang, Hebei Province: a primary study].

    Science.gov (United States)

    Cui, Ming-xing; He, Xing-yuan; Chen, Wei; Chen, Zhen-ju; Zhou, Chang-hong; Wu, Tao

    2008-11-01

    Dendroclimatic methods were used to investigate the relationships between the growth of Chinese pine (Pinus tabulaeformis Carr.) and the climatic parameters in Mulan-Weichang of Hebei Province. The results showed that Chinese pine presented high sensitivity to climatic changes, and its earlywood width showed the highest sensitivity. There was a significant negative correlation between the tree-ring width chronology of Chinese pine and the air temperature in May-June. The precipitation and relative humidity in June had strong positive effects on the growth of earlywood, the precipitation from September to next September had significant positive effects on Chinese pine growth, and the relative humidity in winter more strongly affected the growth of latewood than of earlywood. There was a definite correlation between the tree-ring width chronology of Chinese pine and the large scale climate fluctuation. From 1951 to 2006, the increase of air temperature in study area was significant, and the sensitivity of Chinese pine to the variations of local temperature and precipitation decreased, presenting an inverse transforming trend with increasing temperature. Greater differences were observed between the reconstructed and observed data of mean temperature in May - June in a century scale, suggesting that the tree-ring growth of Chinese pine in study area had a greater fluctuation of sensitivity to the variation of climatic factors.

  10. Entrepreneurial orientation of eastern white pine primary producers and secondary manufacturers: A regional phenomenon?

    Science.gov (United States)

    Delton Alderman

    2011-01-01

    Eastern white pine (EWP) and red pine make up nearly 8.5 percent of the total sawtimber volume in the New England, Mid-Atlantic, and Lake States regions. The majority of white pine growing stock is found in the Mid-Atlantic and Lake State regions; however, the center of eastern white pine production and markets is in New England. EWP is produced in both hardwood...

  11. 7 CFR 160.91 - Meaning of words “pine” and “pine tree.”

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Meaning of words âpineâ and âpine tree.â 160.91... REGULATIONS AND STANDARDS FOR NAVAL STORES Labeling, Advertising and Packing § 160.91 Meaning of words “pine” and “pine tree.” The words “pine” or “pine tree,” when used to designate the source of spirits of...

  12. CO dissociation on magnetic Fen clusters

    KAUST Repository

    Jedidi, Abdesslem

    2014-01-01

    This work theoretically investigates the CO dissociation on Fen nanoparticles, for n in the range of 1-65, focusing on size dependence in the context of the initial step of the Fischer-Tropsch reaction. CO adsorbs molecularly through its C-end on a triangular facet of the nanoparticle. Dissociation becomes easier when the cluster size increases. Then, the C atom is bonded to a square facet that is generated as a result of the adsorption if it does not yet exist in the bare cluster, while the O atom is adsorbed on a triangular facet. In the most stable situation, the two adsorbed atoms remain close together, both having in common one shared first-neighbor iron atom. There is a partial spin quenching of the neighboring Fe atoms, which become more positively charged than the other Fe atoms. The shared surface iron atom resembles a metal-cation from a complex. Despite the small size of the iron cluster considered, fluctuations due to specific configurations do not influence properties for n > 25 and global trends seem significant.

  13. Southern pine beetle infestations in relation to forest stand conditions, previous thinning, and prescribed burning: evaluation of the Southern Pine Beetle Prevention Program

    Science.gov (United States)

    John T. Nowak; James R. Meeker; David R. Coyle; Chris A. Steiner; Cavell Brownie

    2015-01-01

    Since 2003, the Southern Pine Beetle Prevention Program (SPBPP) (a joint effort of the USDA Forest Service and Southern Group of State Foresters) has encouraged and provided cost-share assistance for silvicultural treatments to reduce stand/forest susceptibility to the southern pine beetle (SPB)(Dendroctonus frontalis Zimmermann) in the southeastern United States....

  14. Characteristics of Blister Rust Cankers on Eastern White Pine

    Science.gov (United States)

    William R. Phelps; Ray Weber

    1969-01-01

    The growth, development, and sporulation of white pine blister rust cankers were studied on eastern white pine in Wisconsin and Minnesota. Three district canker types were identified on the basis of physical appearance, growth rate, and sporulation. Canker growth rate and sporulation decreased as tree size or age increased, and many cankers apparently became inactive...

  15. El fenómeno del acoso laboral entre los trabajadores de la universidad O fenômeno mobbing entre os trabalhadores da universidade The phenomenon of mobbing among university employees

    Directory of Open Access Journals (Sweden)

    Fernando Justicia Justicia

    2007-12-01

    Full Text Available El objetivo del artículo es realizar una descripción del fenómemo mobbing -acoso laboral- en el contexto de la universidad. Los trabajos realizadossobre este problema no son muy prolíficos lo que puede explicar la gran dificultad para caracterizar el fenómeno en el ámbito universitario. En el presente trabajo presentamos los niveles de incidencia del acoso laboral entre la población universitaria, los tipos de acoso más frecuentes y los efectos producidos en las víctimas, con la finalidad de caracterizar y definir el problema. Al mismo tiempo, intentamos conocer la influencia de determinadas variables como la edad, género y tiempo de victimización. En este sentido, y de acuerdo con otros estudios realizados, encontramos diferencias estadísticas en función del género de las víctimas. Del mismo modo, los resultados apuntan que la frecuencia y duración del acoso laboral afectan negativamente a las víctimas provocando un empeoramiento de los efectos derivados del acoso.O objetivo deste artigo é realizar uma descrição do fenômeno mobbing -tormento e persecução no lugar do trabalho- no contexto da universidade. Há poucos trabalhos realizados sob este problema nos contextos de educação superior o que pode explicar a grande dificuldade para caracterizar o fenômeno no âmbito universitário. Neste artigo apresentamos os níveis de incidência entre a população universitária, os tipos de mobbing mais freqüentes e os efeitos produzidos nas vítimas com a finalidade de caracterizar e definir o problema. Ao mesmo tempo, tentamos conhecer a influência de determinadas variáveis tais como a idade, gênero ou o tempo de exposição ao fenômeno. Neste sentido, e em concordância com outros estudos realizados, encontramos diferenças estatísticas em função do gênero das vítimas. De igual forma, os dados apontam que a freqüência e duração da situação de persecução no trabalho afetam negativamente as vítimas provocando

  16. Rehabilitation of acidified and eutrophied fens in The Netherlands : Effects of hydrologic manipulation and liming

    NARCIS (Netherlands)

    Beltman, B.; Broek, T. van den; Barendregt, A.; Bootsma, M.C.; Grootjans, A.P.

    Mosaic fen communities with many rare plant species were outcompeted by fast-growing bryophyte stands (Sphagnum flexuosum/Sphagnum fallax and Polytrichum commune). Eutrophication and acidification were the main causes. Management experiments were carried out to set back this succession by restoring

  17. Biochemical processes of oligotrophic peat deposits of Vasyugan Mire

    Science.gov (United States)

    Inisheva, L. I.; Sergeeva, M. A.

    2009-04-01

    The problem of peat and mire ecosystems functioning and their rational use is the main problem of biosphere study. This problem also refers to forecasting of biosphere changes results which are global and anthropogenic. According to many scientists' research the portion of mires in earth carbon balance is about 15% of world's stock. The aim of this study is to investigate biochemical processes in oligotrophic deposits in North-eastern part of Vasyugan Mire. The investigations were made on the territory of scientific-research ground (56˚ 03´ and 56˚ 57´ NL, 82˚ 22´ and 82˚ 42´ EL). It is situated between two rivers Bakchar and Iksa (in outskirts of the village Polynyanka, Bakchar region, Tomsk oblast). Evolution of investigated mire massif began with the domination of eutrophic phytocenosis - Filicinae, then sedge. Later transfer into oligotrophic phase was accompanied by formation of meter high-moor peat deposit. The age of three-meter peat deposit reaches four thousand years. Biochemical processes of carbon cycle cover the whole peat deposit, but the process activity and its direction in different layers are defined by genesis and duration of peat formation. So, the number of cellulose-fermenting aerobes in researched peat deposits ranges from 16.8 to 75.5 million CFU/g, and anaerobic bacteria from 9.6 to 48.6 million CFU/g. The high number of aerobes is characteristic for high water levels, organizing by raised bog peats. Their number decreases along the profile in 1.7 - 2 times. The number of microflora in peat deposit is defined by the position in the landscape profile (different geneses), by the depth, by hydrothermic conditions of years and individual months. But microflora activity shows along all depth of peat deposit. We found the same in the process of studying of micromycete complex structure. There was revealed either active component micromycete complex - mycelium, or inert one - spores in a meter layer of peat deposit. If mushrooms

  18. Synthesis and Characterization of Pine Needles Reinforced RF Matrix Based Biocomposites

    Directory of Open Access Journals (Sweden)

    A. S. Singha

    2008-01-01

    Full Text Available Synthesis and characterization of pine needles reinforced thermosetting resin (Resorcinol-Formaldehyde which is most suitable as composite matrix has been reported. The polycondensation reaction between resorcinol and formaldehyde (RF in different molar ratios has been applied to the synthesis of RF polymer matrix. A thermosetting resin based composite, containing approximately 10, 20, 30 and 40% of natural fiber by weight, has been obtained by adding pine needles to the Resorcinol-Formaldehyde (RF resin. The mechanical properties of randomly oriented intimately mixed particle reinforced (Pine needles composites were determined. Effect of fiber loading in terms of weight % on mechanical properties such as tensile, compressive, and flexural and wear properties have also been evaluated. The reinforcing of the resin with Pine needles was accomplished in particle size of 200 micron by employing optimized resin. Present work reveals that mechanical properties of the RF resin increases to extensive extent when reinforced with Pine needles. Thermal (TGA/DTA and morphological studies (SEM of the resin, fiber and polymer composites thus synthesized have also been carried out.

  19. Reciprocal selection causes a coevolutionary arms race between crossbills and lodgepole pine.

    Science.gov (United States)

    Benkman, Craig W; Parchman, Thomas L; Favis, Amanda; Siepielski, Adam M

    2003-08-01

    Few studies have shown both reciprocal selection and reciprocal adaptations for a coevolving system in the wild. The goal of our study was to determine whether the patterns of selection on Rocky Mountain lodgepole pine (Pinus contorta spp. latifolia) and red crossbills (Loxia curvirostra complex) were concordant with earlier published evidence of reciprocal adaptations in lodgepole pine and crossbills on isolated mountain ranges in the absence of red squirrels (Tamiasciurus hudsonicus). We found that selection (directional) by crossbills on lodgepole pine where Tamiasciurus are absent was divergent from the selection (directional) exerted by Tamiasciurus on lodgepole pine. This resulted in divergent selection between areas with and without Tamiasciurus that was congruent with the geographic patterns of cone variation. In the South Hills, Idaho, where Tamiasciurus are absent and red crossbills are thought to be coevolving with lodgepole pine, crossbills experienced stabilizing selection on bill size, with cone structure as the agent of selection. These results show that crossbills and lodgepole pine exhibit reciprocal adaptations in response to reciprocal selection, and they provide insight into the traits mediating and responding to selection in a coevolutionary arms race.

  20. A basic study on the development of deodorants using pine needle oil

    Energy Technology Data Exchange (ETDEWEB)

    Doh, K.S.; Lee, H.J. [Department of Chemical Engineering, Soongsil University, Seoul (Korea, Republic of); Kim, D.K. [Chemical Technology Division, Korea Research Institute of Chemical Technology, Taejon (Korea, Republic of)

    1997-11-01

    The basic study on the development of deodorant made from pine needle oil was performed. The pine needle oil(PNO) was analysed using GC, GC/MS and FT-1R analyzer for analysis of chemical concentration, chemical components and structure. The analysis results obtained from GC and GC/MS analyzer were composed to main components of {alpha},{beta}-Pinene(C{sub 10}H{sub 16}), 3-Carene (C{sub 10}H{sub 16}), {Upsilon}-terpinene(C{sub 10}H{sub 16}) and terpinolene(C{sub 10}H{sub 16}), etc. Also, the concentration of heavy metals analysed from AAS analyzer. The COD and BOD concentration of landfill leachate with pine needle oil were surveyed. As a results, the pine needle oil extracted from pine needles can be used to remove bad smells of wastes as a deodorant. (author). 13 refs., 3 figs., 3 tabs.

  1. Composition and structure of managed pine stands compared to reference longleaf pine sites on Marine Corps Base Camp Lejeune, North Carolina

    Science.gov (United States)

    Joan L. Walker; Andrea M. Silletti; Susan Cohen

    2010-01-01

    We sampled the ground layer of 28 pine plantations to compare with ecological reference sites at Marine Corps Base, Camp Lejeune (MCBCL), NC. Plantations were ≥ 18 years old and had been burned within the previous year. Pines had been hand-planted on beds or fl at-planted, and the plantations were burned every 3 to 4 years after age 7. Data from 39 reference sites were...

  2. Herbaceous weed control in loblolly pine plantations using flazasulfuron

    Science.gov (United States)

    Andrew W. Ezell; Jimmie L. Yeiser

    2015-01-01

    A total of 13 treatments were applied at four sites (two in Mississippi and two in Texas) to evaluate the efficacy of flazasulfuron applied alone or in mixtures for providing control of herbaceous weeds. All sites were newly established loblolly pine (Pinus taeda L.) plantations. Plots were evaluated monthly until 180 days after treatment. No phytotoxicity on pine...

  3. Interacting genes in the pine-fusiform rust forest pathosystem

    Science.gov (United States)

    H.V. Amerson; T.L. Kubisiak; S.A. Garcia; G.C. Kuhlman; C.D. Nelson; S.E. McKeand; T.J. Mullin; B. Li

    2005-01-01

    Fusiform rust (FR) disease of pines, caused by Cronartium quercuum f.sp. fusiforme (Cqf), is the most destructive disease in pine plantations of the southern U. S. The NCSU fusiform rust program, in conjunction with the USDA-Forest Service in Saucier, MS and Athens, GA, has research underway to elucidate some of the genetic interactions in this...

  4. Silvicultural recommendations for the management of ponderosa pine forest

    Science.gov (United States)

    Martin Alfonso Mendoza Briseno; Mary Ann Fajvan; Juan Manuel Chacon Sotelo; Alejandro Velazquez Martinez; Antonio Quinonez. Silva

    2014-01-01

    Ponderosa pines are the most important timber producing species in Mexico, and they also represent a major portion of the Usa and Canada timber production. These pines form near pure stands with simple and stable stand structure. They suffer only occasional disturbances, and they sustain a limited capacity to hold biodiversity and other senvironmental services. The...

  5. Susceptibility of ponderosa pine, Pinus ponderosa (Dougl. Ex Laws.), to mountain pine beetle, Dendroctonus ponderosae Hopkins, attack in uneven-aged stands in the Black Hills of South Dakota and Wyoming USA

    Science.gov (United States)

    Jose F. Negron; Kurt Allen; Blaine Cook; John R. Withrow

    2008-01-01

    Mountain pine beetle, Dendroctonus ponderosae Hopkins can cause extensive tree mortality in ponderosa pine, Pinus ponderosa Dougl. ex Laws., forests in the Black Hills of South Dakota and Wyoming. Most studies that have examined stand susceptibility to mountain pine beetle have been conducted in even-aged stands. Land managers...

  6. PINE-SPARKY.2 for automated NMR-based protein structure research.

    Science.gov (United States)

    Lee, Woonghee; Markley, John L

    2018-05-01

    Nuclear magnetic resonance (NMR) spectroscopy, along with X-ray crystallography and cryoelectron microscopy, is one of the three major tools that enable the determination of atomic-level structural models of biological macromolecules. Of these, NMR has the unique ability to follow important processes in solution, including conformational changes, internal dynamics and protein-ligand interactions. As a means for facilitating the handling and analysis of spectra involved in these types of NMR studies, we have developed PINE-SPARKY.2, a software package that integrates and automates discrete tasks that previously required interaction with separate software packages. The graphical user interface of PINE-SPARKY.2 simplifies chemical shift assignment and verification, automated detection of secondary structural elements, predictions of flexibility and hydrophobic cores, and calculation of three-dimensional structural models. PINE-SPARKY.2 is available in the latest version of NMRFAM-SPARKY from the National Magnetic Resonance Facility at Madison (http://pine.nmrfam.wisc.edu/download_packages.html), the NMRbox Project (https://nmrbox.org) and to subscribers to the SBGrid (https://sbgrid.org). For a detailed description of the program, see http://www.nmrfam.wisc.edu/pine-sparky2.htm. whlee@nmrfam.wisc.edu or markley@nmrfam.wisc.edu. Supplementary data are available at Bioinformatics online.

  7. Fatty Acid Composition of Novel Host Jack Pine Do Not Prevent Host Acceptance and Colonization by the Invasive Mountain Pine Beetle and Its Symbiotic Fungus

    Science.gov (United States)

    Ishangulyyeva, Guncha; Najar, Ahmed; Curtis, Jonathan M.

    2016-01-01

    Fatty acids are major components of plant lipids and can affect growth and development of insect herbivores. Despite a large literature examining the roles of fatty acids in conifers, relatively few studies have tested the effects of fatty acids on insect herbivores and their microbial symbionts. Particularly, whether fatty acids can affect the suitability of conifers for insect herbivores has never been studied before. Thus, we evaluated if composition of fatty acids impede or facilitate colonization of jack pine (Pinus banksiana) by the invasive mountain pine beetle (Dendroctonus ponderosae) and its symbiotic fungus (Grosmannia clavigera). This is the first study to examine the effects of tree fatty acids on any bark beetle species and its symbiotic fungus. In a novel bioassay, we found that plant tissues (hosts and non-host) amended with synthetic fatty acids at concentrations representative of jack pine were compatible with beetle larvae. Likewise, G. clavigera grew in media amended with lipid fractions or synthetic fatty acids at concentrations present in jack pine. In contrast, fatty acids and lipid composition of a non-host were not suitable for the beetle larvae or the fungus. Apparently, concentrations of individual, rather than total, fatty acids determined the suitability of jack pine. Furthermore, sampling of host and non-host tree species across Canada demonstrated that the composition of jack pine fatty acids was similar to the different populations of beetle’s historical hosts. These results demonstrate that fatty acids composition compatible with insect herbivores and their microbial symbionts can be important factor defining host suitability to invasive insects. PMID:27583820

  8. Efficacy of verbenone for protecting ponderosa pine stands from western pine beetle (Coleoptera: Curculionidae: Scolytinae) attack in California.

    Science.gov (United States)

    Fettig, Christopher J; McKelvey, Stephen R; Borys, Robert R; Dabney, Christopher P; Hamud, Shakeeb M; Nelson, Lori J; Seybold, Steven J

    2009-10-01

    The western pine beetle, Dendroctonus brevicomis LeConte (Coleoptera: Curculionidae: Scolytinae), is a major cause of ponderosa pine, Pinus ponderosa Dougl. ex Laws., mortality in much of western North America. Currently, techniques for managing D. brevicomis infestations are limited. Verbenone (4,6,6-trimethylbicyclo [3.1.1] hept-3-en-2-one) is an antiaggregation pheromone of several Dendroctonus spp., including D. brevicomis, and it has been registered as a biopesticide for control of mountain pine beetle, Dendroctonus ponderosae Hopkins, and southern pine beetle, Dendroctonus frontalis Zimmermann. We evaluated the efficacy of a 5-g verbenone pouch [82%-(-); 50 mg/d] applied at 125 Ulha for protecting P. ponderosa stands (2 ha) from D. brevicomis attack over a 3-yr period. No significant differences in levels of D. brevicomis-caused tree mortality or the percentage of unsuccessfully attacked trees were found between verbenone-treated and untreated plots during each year or cumulatively over the 3-yr period. Laboratory analyses of release rates and chemical composition of volatiles emanating from verbenone pouches after field exposure found no deterioration of the active ingredient or physical malfunction of the release device. The mean release rate of pouches from all locations and exposure periods was 44.5 mg/d. In a trapping bioassay, the range of inhibition of the 5-g verbenone pouch was determined to be statistically constant 2 m from the release device. We discuss the implications of these and other results to the development of verbenone as a semiochemical-based tool for management of D. brevicomis infestations in P. ponderosa stands.

  9. Evolution of conifer diterpene synthases: diterpene resin acid biosynthesis in lodgepole pine and jack pine involves monofunctional and bifunctional diterpene synthases.

    Science.gov (United States)

    Hall, Dawn E; Zerbe, Philipp; Jancsik, Sharon; Quesada, Alfonso Lara; Dullat, Harpreet; Madilao, Lina L; Yuen, Macaire; Bohlmann, Jörg

    2013-02-01

    Diterpene resin acids (DRAs) are major components of pine (Pinus spp.) oleoresin. They play critical roles in conifer defense against insects and pathogens and as a renewable resource for industrial bioproducts. The core structures of DRAs are formed in secondary (i.e. specialized) metabolism via cycloisomerization of geranylgeranyl diphosphate (GGPP) by diterpene synthases (diTPSs). Previously described gymnosperm diTPSs of DRA biosynthesis are bifunctional enzymes that catalyze the initial bicyclization of GGPP followed by rearrangement of a (+)-copalyl diphosphate intermediate at two discrete class II and class I active sites. In contrast, similar diterpenes of gibberellin primary (i.e. general) metabolism are produced by the consecutive activity of two monofunctional class II and class I diTPSs. Using high-throughput transcriptome sequencing, we discovered 11 diTPS from jack pine (Pinus banksiana) and lodgepole pine (Pinus contorta). Three of these were orthologous to known conifer bifunctional levopimaradiene/abietadiene synthases. Surprisingly, two sets of orthologous PbdiTPSs and PcdiTPSs were monofunctional class I enzymes that lacked functional class II active sites and converted (+)-copalyl diphosphate, but not GGPP, into isopimaradiene and pimaradiene as major products. Diterpene profiles and transcriptome sequences of lodgepole pine and jack pine are consistent with roles for these diTPSs in DRA biosynthesis. The monofunctional class I diTPSs of DRA biosynthesis form a new clade within the gymnosperm-specific TPS-d3 subfamily that evolved from bifunctional diTPS rather than monofunctional enzymes (TPS-c and TPS-e) of gibberellin metabolism. Homology modeling suggested alterations in the class I active site that may have contributed to their functional specialization relative to other conifer diTPSs.

  10. Variable nutrient stoichiometry (carbon:nitrogen:phosphorus) across trophic levels determines community and ecosystem properties in an oligotrophic mangrove system.

    Science.gov (United States)

    Scharler, U M; Ulanowicz, R E; Fogel, M L; Wooller, M J; Jacobson-Meyers, M E; Lovelock, C E; Feller, I C; Frischer, M; Lee, R; McKee, K; Romero, I C; Schmit, J P; Shearer, C

    2015-11-01

    Our study investigated the carbon:nitrogen:phosphorus (C:N:P) stoichiometry of mangrove island of the Mesoamerican Barrier Reef (Twin Cays, Belize). The C:N:P of abiotic and biotic components of this oligotrophic ecosystem was measured and served to build networks of nutrient flows for three distinct mangrove forest zones (tall seaward fringing forest, inland dwarf forests and a transitional zone). Between forest zones, the stoichiometry of primary producers, heterotrophs and abiotic components did not change significantly, but there was a significant difference in C:N:P, and C, N, and P biomass, between the functional groups mangrove trees, other primary producers, heterotrophs, and abiotic components. C:N:P decreased with increasing trophic level. Nutrient recycling in the food webs was highest for P, and high transfer efficiencies between trophic levels of P and N also indicated an overall shortage of these nutrients when compared to C. Heterotrophs were sometimes, but not always, limited by the same nutrient as the primary producers. Mangrove trees and the primary tree consumers were P limited, whereas the invertebrates consuming leaf litter and detritus were N limited. Most compartments were limited by P or N (not by C), and the relative depletion rate of food sources was fastest for P. P transfers thus constituted a bottleneck of nutrient transfer on Twin Cays. This is the first comprehensive ecosystem study of nutrient transfers in a mangrove ecosystem, illustrating some mechanisms (e.g. recycling rates, transfer efficiencies) which oligotrophic systems use in order to build up biomass and food webs spanning various trophic levels.

  11. Variable nutrient stoichiometry (carbon:nitrogen:phosphorus) across trophic levels determines community and ecosystem properties in an oligotrophic mangrove system

    Science.gov (United States)

    Scharler, U.M.; Ulanowicz, Robert E.; Fogel, M.L.; Wooller, M.J.; Jacobson-Meyers, M.E.; Lovelock, C.E.; Feller, I.C.; Frischer, M.; Lee, R.; Mckee, Karen L.; Romero, I.C.; Schmit, J.P.; Shearer, C.

    2015-01-01

    Our study investigated the carbon:nitrogen:phosphorus (C:N:P) stoichiometry of mangrove island of the Mesoamerican Barrier Reef (Twin Cays, Belize). The C:N:P of abiotic and biotic components of this oligotrophic ecosystem was measured and served to build networks of nutrient flows for three distinct mangrove forest zones (tall seaward fringing forest, inland dwarf forests and a transitional zone). Between forest zones, the stoichiometry of primary producers, heterotrophs and abiotic components did not change significantly, but there was a significant difference in C:N:P, and C, N, and P biomass, between the functional groups mangrove trees, other primary producers, heterotrophs, and abiotic components. C:N:P decreased with increasing trophic level. Nutrient recycling in the food webs was highest for P, and high transfer efficiencies between trophic levels of P and N also indicated an overall shortage of these nutrients when compared to C. Heterotrophs were sometimes, but not always, limited by the same nutrient as the primary producers. Mangrove trees and the primary tree consumers were P limited, whereas the invertebrates consuming leaf litter and detritus were N limited. Most compartments were limited by P or N (not by C), and the relative depletion rate of food sources was fastest for P. P transfers thus constituted a bottleneck of nutrient transfer on Twin Cays. This is the first comprehensive ecosystem study of nutrient transfers in a mangrove ecosystem, illustrating some mechanisms (e.g. recycling rates, transfer efficiencies) which oligotrophic systems use in order to build up biomass and food webs spanning various trophic levels.

  12. Complete Chloroplast Genome of the Wollemi Pine (Wollemia nobilis): Structure and Evolution.

    Science.gov (United States)

    Yap, Jia-Yee S; Rohner, Thore; Greenfield, Abigail; Van Der Merwe, Marlien; McPherson, Hannah; Glenn, Wendy; Kornfeld, Geoff; Marendy, Elessa; Pan, Annie Y H; Wilton, Alan; Wilkins, Marc R; Rossetto, Maurizio; Delaney, Sven K

    2015-01-01

    The Wollemi pine (Wollemia nobilis) is a rare Southern conifer with striking morphological similarity to fossil pines. A small population of W. nobilis was discovered in 1994 in a remote canyon system in the Wollemi National Park (near Sydney, Australia). This population contains fewer than 100 individuals and is critically endangered. Previous genetic studies of the Wollemi pine have investigated its evolutionary relationship with other pines in the family Araucariaceae, and have suggested that the Wollemi pine genome contains little or no variation. However, these studies were performed prior to the widespread use of genome sequencing, and their conclusions were based on a limited fraction of the Wollemi pine genome. In this study, we address this problem by determining the entire sequence of the W. nobilis chloroplast genome. A detailed analysis of the structure of the genome is presented, and the evolution of the genome is inferred by comparison with the chloroplast sequences of other members of the Araucariaceae and the related family Podocarpaceae. Pairwise alignments of whole genome sequences, and the presence of unique pseudogenes, gene duplications and insertions in W. nobilis and Araucariaceae, indicate that the W. nobilis chloroplast genome is most similar to that of its sister taxon Agathis. However, the W. nobilis genome contains an unusually high number of repetitive sequences, and these could be used in future studies to investigate and conserve any remnant genetic diversity in the Wollemi pine.

  13. Response of anaerobic carbon cycling to water table manipulation in an Alaskan rich fen

    Science.gov (United States)

    E.S. Kane; M.R. Chivers; M.S. Turetsky; C.C. Treat; D.G. Petersen; M. Waldrop; J.W. Harden; A.D. McGuire

    2013-01-01

    To test the effects of altered hydrology on organic soil decomposition, we investigated CO2 and CH4 production potential of rich-fen peat (mean surface pH = 6.3) collected from a field water table manipulation experiment including control, raised and lowered water table treatments. Mean anaerobic CO2...

  14. BOREAS TGB-1/TGB-3 CH4 Chamber Flux Data over the NSA Fen

    Science.gov (United States)

    Bubier, Jill L.; Moore, Tim R.; Hall, Forrest G. (Editor); Conrad, Sara K. (Editor)

    2000-01-01

    The BOREAS TGB-3 team collected methane (CH4) chamber flux measurements at the NSA fen site during May-September 1994 and June-October 1996. Gas samples were extracted approximately every 7 days from chambers and analyzed at the NSA lab facility. The data are provided in tabular ASCII files.

  15. Partitioning of habitat effects casts light on the decline of the fen orchid, Liparis loeselii

    DEFF Research Database (Denmark)

    Andersen, Dagmar Kappel; Ejrnæs, Rasmus; Minter, Martine Olesen

    2015-01-01

    Liparis loeselii is a rare and declining orchid species restricted to rich fens in the northern hemisphere. Suggested reasons for the decline are habitat destruction, eutrophication, altered hydrology and scrub encroachment after termination of traditional management such as grazing and hay making...

  16. Biodegradación de compuestos fenólicos del alpechín con Aspergillus terreus

    Directory of Open Access Journals (Sweden)

    García Paeja, María P.

    1992-04-01

    Full Text Available Olive mill wastewater degradation by Aspergillus terreus and under aerobic conditions at 28°C, was measured by the parameter of phenol content. We have explored the effect of different concentrations of olive mill wastewater upon the activity of Aspergillus terreus. Through HPLC, 10 phenol compounds (90% of the total phenolic content of the olive mill wastewater were identified.Se estudia la degradación de alpechines con Aspergillus terreus en condiciones de aerobiosis y temperatura de 28°C, utilizando como parámetro el contenido fenólico. Se analiza el efecto de la concentración de alpechín con Aspergillus terreus utilizando el mismo parámetro. Se han identificado por cromatografía líquida de alta eficacia (CLAE 10 compuestos fenólicos que suponen el 90% del total del alpechín.

  17. "Reversed" intraguild predation: red fox cubs killed by pine marten.

    Science.gov (United States)

    Brzeziński, Marcin; Rodak, Lukasz; Zalewski, Andrzej

    2014-01-01

    Camera traps deployed at a badger Meles meles set in mixed pine forest in north-eastern Poland recorded interspecific killing of red fox Vulpes vulpes cubs by pine marten Martes martes . The vixen and her cubs settled in the set at the beginning of May 2013, and it was abandoned by the badgers shortly afterwards. Five fox cubs were recorded playing in front of the den each night. Ten days after the first recording of the foxes, a pine marten was filmed at the set; it arrived in the morning, made a reconnaissance and returned at night when the vixen was away from the set. The pine marten entered the den several times and killed at least two fox cubs. It was active at the set for about 2 h. This observation proves that red foxes are not completely safe from predation by smaller carnivores, even those considered to be subordinate species in interspecific competition.

  18. White pine in the American West: A vanishing species - can we save it?

    Science.gov (United States)

    Leon F. Neuenschwander; James W. Byler; Alan E. Harvey; Geral I. McDonald; Denise S. Ortiz; Harold L. Osborne; Gerry C. Snyder; Arthur Zack

    1999-01-01

    Forest scientists ask that everyone, from the home gardener to the forest manager, help revive western white pine by planting it everywhere, even in nonforest environments such as our neighborhood streets, parks, and backyards. White pine, long ago considered the "King Pine," once dominated the moist inland forests of the Northwest, eventually spawning whole...

  19. Forest stand dynamics of shortleaf pine in the Ozarks

    Science.gov (United States)

    David R. Larsen

    2007-01-01

    Much has been written on the management of shortleaf pine in the Ozarks (Brinkman et al. 1965, Brinkman 1967, Brinkman and Smith 1968, Seidel and Rogers 1965, Seidel and Rogers 1966). In large portions of the Ozarks, shortleaf pine does not grow in pure stands but rather in mixes with various oak species. These mixes present unique challenges in finding the set of...

  20. Longleaf pine forests and woodlands: old growth under fire!

    Science.gov (United States)

    Joan L. Walker

    1999-01-01

    The author discusses a once widespread forest type of the Southeast – longleaf pine dominated forests and woodlands. This system depends on fire – more or less frequent, and often of low intensity. Because human-mediated landscape fragmentation has drastically changed the behavior of fire on longleaf pine dominated landscapes, these forests and woodlands will never be...

  1. Emergence of Buprestidae, Cerambycidae, and Scolytinae (Coleoptera) from mountain pine beetle-killed and fire-killed ponderosa pines in the Black Hills, South Dakota, USA

    Science.gov (United States)

    Sheryl L. Costello; William R. Jacobi; Jose F. Negron

    2013-01-01

    Wood borers (Coleoptera: Cerambycidae and Buprestidae) and bark beetles (Coleoptera: Curculionidae) infest ponderosa pines, Pinus ponderosa P. Lawson and C. Lawson, killed by mountain pine beetle (MPB), Dendroctonus ponderosae Hopkins, and fire. No data is available comparing wood borer and bark beetle densities or species guilds associated with MPB-killed or fire-...

  2. Variable-retention harvesting as a silvicultural option for lodgepole pine

    Science.gov (United States)

    Christopher R. Keyes; Thomas E. Perry; Elaine K. Sutherland; David K. Wright; Joel M. Egan

    2014-01-01

    Bark beetle-induced mortality in forested landscapes of structurally uniform, even-aged lodgepole pine stands has inspired a growing interest in the potential of silvicultural treatments to enhance resilience by increasing spatial and vertical complexity. Silvicultural treatments can simulate mixed-severity disturbances that create multiaged lodgepole pine stands,...

  3. Spatial and population genetic structure of microsatellites in white pine

    Science.gov (United States)

    Paula E. Marquardt; Bryan K. Epperson

    2004-01-01

    We evaluated the population genetic structure of seven microsatellite loci for old growth and second growth populations of eastern white pine (Pinus strobus). From each population, located within Hartwick Pines State Park, Grayling, Michigan, USA, 120-122 contiguous trees were sampled for genetic analysis. Within each population, genetic diversity...

  4. Genetic conservation and management of the Californian endemic, Torrey Pine (Pinus torreyana Parry)

    Science.gov (United States)

    Jill A. Hamilton; Jessica W. Wright; F. Thomas. Ledig

    2017-01-01

    Torrey pine (Pinus torreyana) is one of the rarest pine species in the world. Restricted to one mainland and one island population in California, Torrey pine is a species of conservation concern under threat due to low population sizes, lack of genetic variation, and environmental stochasticity. Previous research points to a lack of within population variation that is...

  5. The role of cell membranes in the regulation of lignification in pine cells

    Science.gov (United States)

    Hendrix, D. L.

    1978-01-01

    The identity of pine cell membranes bearing PAL enzyme activity, the isolation of a plasma membrane preparation from pine cells for testing as a regulatory barrier in lignification, and the measurement of the geopotential effect in pine stems are presented. A model to describe and predict the interaction of gravity and lignification of higher plants was developed.

  6. Effects of Reduced and Oxidised Nitrogen on Rich-Fen Mosses: a 4-Year Field Experiment

    NARCIS (Netherlands)

    Paulissen, Maurice P.C.P.; Bobbink, Roland; Robat, Sandra A.; Verhoeven, Jos T.A.

    2016-01-01

    Dutch fens, subjected to high nitrogen (N) deposition levels with reduced N (NHy) highly dominating over oxidised N (NOx), have since the second half of the past century seen a significant decline of Scorpidium and other characteristic brown moss species, while several Sphagnum species have

  7. Bartonellosis y fenómeno de Mooser

    Directory of Open Access Journals (Sweden)

    Hernando Groot

    1941-02-01

    Full Text Available Es conocido el fenómeno o reacción de Mooser que este investigador lograra al inocular a un curí por vía intraperitoneal sangre de un tifoso exantemático mejicano, y que consiste en una edema escroto-testicular bastante típico (1-6. En líneas generales se puede decir que un curí inoculado intraperitonealmente con sangre de un tifoso exantemático, presenta después de un período de incubación que varía entre dos días y dos semanas (variación que depende especialmente de las dosis inoculadas uan fiebre de 39,8 a 40,5 que puede durar de 3 a 14 días. Clínicamente la hembra muestra sólo la reacción febril, mientras que en el macho se observan lesiones inflamatorias escroto-testiculares características.

  8. Impact of weed control and fertilization on growth of four species of pine in the Virginia Piedmont

    Science.gov (United States)

    Dzhamal Y. Amishev; Thomas R. Fox

    2006-01-01

    During 1999, a mixed stand of Virginia pine and hardwoods in the Piedmont of Virginia was clearcut and site prepared by burning. Three replications, containing strips of loblolly pine, shortleaf pine, Virginia pine, and Eastern white pine, were planted at a 3 m x 1.5 m spacing during February to June, 2000. The strips were subsequently split to accommodate four...

  9. Effects of gamma radiation and storage on cooked pine seed (Araucaria angustifollia)

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Lucia A.C.S.; Modolo, Debora M.; Martinez, Patricia; Piero, Edson A. di; Bigide, Priscila; Arthur, Valter, E-mail: lcasilva@cena.usp.br, E-mail: arthur@cena.usp.br [Centro de Energia Nuclear na Agricultura (CENA/USP), Laboratorio de Radiobiologia e Ambiente, Piracicaba, SP (Brazil); Harder, Marcia N.C.; Arthur, Paula B. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    The Araucaria angustifolia, is known as the Pinheiro-do-Parana Brazilian pine, Pine, Pine Tree Monkey, emerges as the main representative of the Rain Forest, also known as Araucaria Forest, part of the Atlantic Forest biome (Decree Law 750/1993). Despite being appreciated nutritious food, the gear has been widely used in Brazilian cook as other seeds, and its consumption in the more usual way roasted or boiled, however, certain foods have been developed, such as flour, pine seeds, artisan produced only due to poor commercial expression. Because of this, the aim of this work was to study the effect of storage under vacuum and gamma radiation on samples cooked pinion. Pine seeds after cooking were stored in vacuum packaging and polypropylene irradiated with 0 (control), 0.5, 1.0 and 3.0 kGy. Later they were stored at a temperature of 6 degree C. Analyzes were performed to characterize physical (weight, temperature, percentage of losses) and proximate composition (Humidity, fat, protein, ash and weight loss) of A. angustifolia (Bert.) pine seed after three months of storage. The results indicated that there was no significant difference between treatments at protein parameter. About the other parameters there was an increase humidity and decrease with ash and fat with the treatments. (author)

  10. Effects of gamma radiation and storage on cooked pine seed (Araucaria angustifollia)

    International Nuclear Information System (INIS)

    Silva, Lucia A.C.S.; Modolo, Debora M.; Martinez, Patricia; Piero, Edson A. di; Bigide, Priscila; Arthur, Valter; Harder, Marcia N.C.; Arthur, Paula B.

    2011-01-01

    The Araucaria angustifolia, is known as the Pinheiro-do-Parana Brazilian pine, Pine, Pine Tree Monkey, emerges as the main representative of the Rain Forest, also known as Araucaria Forest, part of the Atlantic Forest biome (Decree Law 750/1993). Despite being appreciated nutritious food, the gear has been widely used in Brazilian cook as other seeds, and its consumption in the more usual way roasted or boiled, however, certain foods have been developed, such as flour, pine seeds, artisan produced only due to poor commercial expression. Because of this, the aim of this work was to study the effect of storage under vacuum and gamma radiation on samples cooked pinion. Pine seeds after cooking were stored in vacuum packaging and polypropylene irradiated with 0 (control), 0.5, 1.0 and 3.0 kGy. Later they were stored at a temperature of 6 degree C. Analyzes were performed to characterize physical (weight, temperature, percentage of losses) and proximate composition (Humidity, fat, protein, ash and weight loss) of A. angustifolia (Bert.) pine seed after three months of storage. The results indicated that there was no significant difference between treatments at protein parameter. About the other parameters there was an increase humidity and decrease with ash and fat with the treatments. (author)

  11. A test of high-dose verbenone for stand-level protection of lodgepole and whitebark pine from mountain pine beetle (Coleoptera: Curculionidae: Scolytinae) attacks

    Science.gov (United States)

    B. J. Bentz; S. Kegley; K. Gibson; R. Their

    2005-01-01

    The effcacy of verbenone as a stand-level protectant against mountain pine beetle, Dendroctonus ponderosae Hopkins, attacks was tested in lodgepole and whitebark pine stands at five geographically separated sites, including three consecutive years at one site. Forty and 20 high-dose pouches, with a verbenone emission rate up to 50 mg/d per pouch, were spaced in a grid...

  12. Effects of Nantucket pine tip moth insecticide spray schedules on loblolly pine seedlings

    Science.gov (United States)

    Christopher J. Fettig; Kenneth W. McCravy; C. Wayne Berisford

    2000-01-01

    Frequent and prolonged insecticide applications to control the Nantucket pine tip moth, Rhyacionia frustrana (Comstock) (Lepidoptera:Torticidae) (NPTM), although effective, may be impractical and uneconomica1, for commercial timber production. Timed insecticide sprays of permethrin (Polmce 3.2® EC) were applied to all possible combinations of spray...

  13. Limited response of ponderosa pine bole defenses to wounding and fungi.

    Science.gov (United States)

    Gaylord, Monica L; Hofstetter, Richard W; Kolb, Thomas E; Wagner, Michael R

    2011-04-01

    Tree defense against bark beetles (Curculionidae: Scolytinae) and their associated fungi generally comprises some combination of constitutive (primary) and induced (secondary) defenses. In pines, the primary constitutive defense against bark beetles consists of preformed resin stored in resin ducts. Induced defenses at the wound site (point of beetle entry) in pines may consist of an increase in resin flow and necrotic lesion formation. The quantity and quality of both induced and constitutive defenses can vary by species and season. The inducible defense response in ponderosa pine is not well understood. Our study examined the inducible defense response in ponderosa pine using traumatic mechanical wounding, and wounding with and without fungal inoculations with two different bark beetle-associated fungi (Ophiostoma minus and Grosmannia clavigera). Resin flow did not significantly increase in response to any treatment. In addition, necrotic lesion formation on the bole after fungal inoculation was minimal. Stand thinning, which has been shown to increase water availability, had no, or inconsistent, effects on inducible tree defense. Our results suggest that ponderosa pine bole defense against bark beetles and their associated fungi is primarily constitutive and not induced.

  14. BOREAS TGB-1/TGB-3 NEE Data over the NSA Fen

    Science.gov (United States)

    Bellisario, Lianne; Hall, Forrest G. (Editor); Conrad, Sara K. (Editor); Moore, Tim R.

    2000-01-01

    The BOReal Ecosystem-Atmosphere Study Trace Gas Biogeochemistry (BOREAS TGB-1) and TGB-3 teams collected several data sets that contributed to understanding the measured trace gas fluxes over sites in the Northern Study Area (NSA). This data set contains Net Ecosystem Exchange of CO2 (NEE) measurements collected with chambers at the NSA fen in 1994 and 1996. Gas samples were extracted approximately every 7 days from chambers and analyzed at the NSA lab facility. The data are provided in tabular ASCII files.

  15. Comparison of Monterey pine stress in urban and natural forests

    Science.gov (United States)

    David J. Nowak; Joe R. McBride

    1991-01-01

    Monterey pine street trees within Carmel, California and its immediate vicinity, as well as forest-grown Monterey pine within adjacent natural stands, were sampled with regard to visual stress characteristics, and various environmental and biological variables. Two stress indices were computed, one hypothesized before data collection was based on relative foliage...

  16. Resistance of three interspecific white pine hybrids to blister rust

    Science.gov (United States)

    R. Z. Callaham

    1962-01-01

    Three white pine hybrids exposed to infection by white pine blister rust (Cronartium ribicola Fischer) since 1946 have inherited the relative resistance of their parental species. The hybrids were produced from controlled pollinations in 1940 and 1941 at the Institute of Forest Genetics, Placerville, Calif. Twelve seedlings of each hybrid were...

  17. Voces actuales en el fenómeno de pasantes de drogas ilícitas en Colombia

    Directory of Open Access Journals (Sweden)

    Galia J. Benítez

    2017-12-01

    Full Text Available Este documento se deriva del análisis realizado a las narrativas de los pasantes de drogas ilícitas denominados popularmente como “mulas”; de manera especial, resalta su mirada localizada sobre el fenómeno del tráfico ilegal de drogas en Colombia. El escrito tiene como objetivo: primero, caracterizar la multiplicidad de conceptos que se utilizan para describir este fenómeno y proponer una definición que abarque diferentes acepciones, y segundo, presentar categorías conceptuales que se desprenden de las narrativas de los pasantes de drogas. Como metodología se utilizó el análisis de contenido, para describir, sistematizar y analizar los testimonios voluntarios de 42 personas imputadas y condenadas como pasantes de drogas ilícitas en Colombia. Esta investigación argumenta que uno de los elementos para entender el fenómeno de los pasantes de drogas ilícitas y su experiencia es su condición de vulnerabilidad. Por un lado, los pasantes ocupan un lugar periférico en las organizaciones narcotraficantes; por otro, son altamente vulnerables al sistema socio-técnico establecido por el Estado para prevenir el transporte de drogas ilícitas. Este estudio muestra que las narrativas de los pasantes de drogas se pueden categorizar en cuatro dicotomías, que sirven como elementos retóricos para la ruptura del binario legalidad/ilegalidad.

  18. Temporal distribution of sediment yield from catchments covered by different pine plantation areas

    Directory of Open Access Journals (Sweden)

    Tyas Mutiara Basuki

    2018-04-01

    Full Text Available Soil erosion and sedimentation are environmental problems faced by tropical countries. Many researches on soil erosion-sedimentation have been conducted with various results. Quantifying soil erosion-sedimentation and its temporal distribution are important for watershed management. Therefore, a study with the objective to quantify the amount of suspended sediment from catchments under various pine plantation areas was conducted. The research was undertaken during 2010 to 2017 in seven catchments with various percentage of pine coverage in Kebumen Regency, Central Java Province. The rainfall data were collected from two rainfall stations. A tide gauge was installed at the outlet of each catchment to monitor stream water level. The water samples for every stream water level increment were analyzed to obtain sediment concentration. The results showed that monthly suspended sediment of the catchments was high in January to April and October to December, and low in May to September. The annual suspended sediment fluctuated during the study period. Non-linear correlations were observed between suspended sediment and rainfall as well as suspended sediment and percentage pine areas. The line trend between suspended sediment and percentage of pine areas showed that the increase in pine areas decreased suspended sediment, with the slope of the graph is sharp at the percentage of pine areas from 8% to 40%, then is gentle for pine plantation areas more than 40%.

  19. Evaluation of mechanical and thermal properties of Pine cone fibers reinforced compatibilized polypropylene

    International Nuclear Information System (INIS)

    Arrakhiz, F.Z.; El Achaby, M.; Benmoussa, K.; Bouhfid, R.; Essassi, E.M.; Qaiss, A.

    2012-01-01

    Highlights: ► Pine cone fibers are used as reinforcement in thermoplastic matrix. ► Pine cone fiber was alkali treated to remove waxes and non cellulosic component. ► Fiber–matrix adhesion was assured by the use of a SEBS-g-MA as a compatibilizer. -- Abstract: Pine cone fibers are a cellulosic material readily available and can be used as reinforcement in a thermoplastic-based composite. A solid knowledge of their fibrillar morphology and structure is required to evaluate their usefulness as a substitute to other abundant natural fibers. Pine cone fibers were alkali treated prior usage to remove waxes and non cellulosic surface component. Fiber–matrix adhesion was assured by both a styrene–(ethylene–butene)–styrene triblock copolymer grafted with maleic anhydride (SEBS-g-MA) and a linear block copolymer based on styrene and butadiene compatibilizer. Scanning Electron Microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction, Thermogravimetric analysis (TGA), tensile and torsional tests were employed for Pine cone polypropylene composite and compatibilized composite at different fiber content. Results show a clear improvement in mechanical properties from the use of both alkali treated Pine cone and Pine cone compatibilized with maleic anhydride, a gain of 43% and 49% respectively in the Young’s modulus, as a results of improved adhesion between fibers and matrix at the interface.

  20. Evaluation on the Efficiency of Subsurface Drainage in Chiu-Fen Landslide at Northern Taiwan

    Science.gov (United States)

    Ying, L. Y.; Lin, D. G.

    2015-12-01

    For administrative district, the Chiu-Fen landslide is situated at northern Taiwan and comes within the jurisdiction of Ruei-Fang district, New Taipei City Government. Chiu-Fen village is a famous spot for sightseeing and tourism in Southeast Asia. In the last decade, for economic purpose, a vast area of slope land in Chiu-Fen area was reclaimed into business and commercial districts. However, due to the complicated geological and hydrological conditions, improper reclamation, and lack of appropriate soil and water conservation facilities, large scale landslides are frequently triggered by typhoon rainfall and causes damages to the transportation and residential building in the community. As a consequence, the government initiated a comprehensive field investigations and remediation plans to stabilize the landslide from 1997 and the remediation works were concentrated on subsurface drainages, namely the application of drainage well (a vertical shaft with multi-level horizontal drainage boreholes). To investigate the efficiency of drainage wells on the landslide, the A1-profile in the landslide which covers the drainage wells W2 and W4 was selected for a series of rainfall seepage and slope stability analyses. In addition, a 48-hrs design rainfall with return period of 25, 50 and 100 years based on the local meteorological data bank was adopted for the analyses. The numerical results indicate the factor safety FS of the three potential sliding surfaces within A1-profile are constantly keeping greater than one (FS > 1.0) and without decreasing with the elapsed time during rainfall. This implies that the subsurface drainage works can drain off the infiltrated rainwater from a high intensity and long duration rainfall and preserve the slope stability of landslides from deterioration. Finally, the efficiency of the drainage wells can be evaluated quantitatively in terms of the time-dependent factor of safety and the pore water pressure distribution on several potential