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Sample records for subalpine poa alpina

  1. Microbial succession of nitrate-reducing bacteria in the rhizosphere of Poa alpina across a glacier foreland in the Central Alps.

    Science.gov (United States)

    Deiglmayr, K; Philippot, L; Tscherko, D; Kandeler, E

    2006-09-01

    Changes in community structure and activity of the dissimilatory nitrate-reducing community were investigated across a glacier foreland in the Central Alps to gain insight into the successional pattern of this functional group and the driving environmental factors. Bulk soil and rhizosphere soil of Poa alpina was sampled in five replicates in August during the flowering stage and in September after the first snowfalls along a gradient from 25 to 129 years after deglaciation and at a reference site outside the glacier foreland (>2000 years deglaciated). In a laboratory-based assay, nitrate reductase activity was determined colorimetrically after 24 h of anaerobic incubation. In selected rhizosphere soil samples, the community structure of nitrate-reducing microorganisms was analysed by restriction fragment length polymorphism (RFLP) analysis using degenerate primers for the narG gene encoding the active site of the membrane-bound nitrate reductase. Clone libraries of the early (25 years) and late (129 years) succession were constructed and representative clones sequenced. The activity of the nitrate-reducing community increased significantly with age mainly due to higher carbon and nitrate availability in the late succession. The community structure, however, only showed a small shift over the 100 years of soil formation with pH explaining a major part (19%) of the observed variance. Clone library analysis of the early and late succession pointed to a trend of declining diversity with progressing age. Presumably, the pressure of competition on the nitrate reducers was relatively low in the early successional stage due to minor densities of microorganisms compared with the late stage; hence, a higher diversity could persist in this sparse environment. These results suggest that the nitrate reductase activity is regulated by environmental factors other than those shaping the genetic structure of the nitrate-reducing community.

  2. Early flowers of Bartsia alpina (Scrophulariaceae) and the visitation by bumblebees

    NARCIS (Netherlands)

    Kwak, MM; Bergman, P

    Phenology and insect visitation of early flowers of Bartsia alpina, a perennial herb, in a subalpine population in northern Sweden, were investigated to find causes for low seed set in early flowers. Bumblebees are the only visitors of B. alpina; they collect pollen and nectar. Flower phenologies of

  3. An updated checklist and key to the open-panicled species of Poa L. (Poaceae) in Peru including three new species, Poa ramoniana, Poa tayacajaensis, and Poa urubambensis

    Science.gov (United States)

    Sylvester, Steven P.; Soreng, Robert J.; Peterson, Paul M.; Sylvester, Mitsy D.P.V.

    2016-01-01

    Abstract We provide an updated checklist and key to the 30 Poa species with open panicles from Peru which includes previously circumscribed Dissanthelium and Aphanelytrum species, new taxon records, and three undescribed species. Poa compressa, Poa grisebachii, and Poa leioclada are recorded from Peru for the first time. A number of species are placed in synonymy: Poa carazensis, Poa ferreyrae and Poa tovarii are synonymized under the name Poa fibrifera; Poa adusta (tentatively) and Poa pilgeri are synonymized under Poa candamoana; Poa superata is synonymized under Poa grisebachii; and Poa paramoensis is synonymized under Poa huancavelicae. Included within this treatment are three new species, Poa ramoniana, Poa tayacajaensis and Poa urubambensis, which are described and illustrated. Poa ramoniana, found growing near lakes in high elevation Puna grasslands of Junín, is similar to a small form of Poa glaberrima, but differs in having rhizomes and growing to only 5 cm tall. Poa tayacajaensis, found from shrublands on Andean slopes of Huancavelica and Huánuco, bears similarities to Poa aequatoriensis but differs in having shorter lemmas which are pubescent between the veins, densely scabrous sheaths with smooth, glabrous throats, and shorter ligules. Poa urubambensis, a common element of the undisturbed Polylepis forest understory of the Cordillera Urubamba, Cusco, is distinct from all other members of open-panicled Poa’s by having glabrous lemmas with a smooth and glabrous callus, and notably small anthers. The type material for the name Poa adusta is discussed and a lectotype is selected. PMID:27489489

  4. Distribution Pattern, Conservation Status, and Associated Flora of the Genus Juniperus in Subalpine Pastures of the Kashmir Himalayas

    Directory of Open Access Journals (Sweden)

    Hamayun Shaheen

    2017-11-01

    Full Text Available Juniperus is an evergreen gymnosperm genus with a broad geographical distribution in the Northern Hemisphere. Juniperus constitutes important vegetation associations in the Himalayan highlands that have significant ecological and socioeconomic importance. This research investigated the distribution pattern, community structure, and ecosystem services provided byJuniperus -dominated subalpine vegetation in the upper Neelum Valley, Pakistan. Vegetation attributes and geographical characteristics were systematically recorded at 4 selected sites. Two species of Juniperus, Juniperus communis L. and J. excelsa M. Bieb., were found to have average importance values of 23.4 and 20.02%, respectively. J. excelsa showed an average basal area of 0.30 m2 ha−1 and an average stem density of 46.95 ha−1; J. communis had an average basal area of 0.25 m2 ha−1 and an average stem density of 33.21 ha−1. A total of 56 Juniperus-associated plant species from 29 families were recorded, with Asteraceae as the dominant family, followed by Lamiaceae, Polygonaceae, Rosaceae, Caryophyllaceae, and Apiaceae. Predominant associated species included Thymus linearis, Aster falconeri, Rosa webbiana, Berberis lyceum, Anagallis arvensis, Rumex nepalensis, Poa alpina, Bistorta affinis, and Iris hookeriana. The calculated average values were Shannon's diversity, 3.07; Simpson's diversity, 0.94; species richness, 1.11; species evenness, 0.90; and maturity index, 45.90. Hemicryptophytes were the dominant lifeform in the area (57.14%, and microphylls (46.42% were the dominant leaf type. Overgrazing and fuelwood cutting were identified as serious threats to both Juniperus species. Restoration of the degraded juniper stands through collective efforts by government and local communities and regular monitoring is recommended.

  5. Transfer of the perfect flower trait from Poa secunda to Poa arachnifera

    Science.gov (United States)

    A Texas bluegrass (Poa arachnifera) population has been developed that successfully integrates the perfect flower trait from Poa secunda through interspecific hybridization. The resulting perfect flowered Texas bluegrass population is perennial, rhizomatous and partially apomictic in its form of re...

  6. ( Arundinaria alpina ) in the Choke Mountain, Northwestern Ethiopia

    African Journals Online (AJOL)

    Propagation Techniques for Highland Bamboo ( Arundinaria alpina ) in the Choke Mountain, Northwestern Ethiopia. ... Ethiopian Journal of Agricultural Sciences ... A. alpina landraces (TIFRO, WELELE and WONDE) were evaluated for their performance under field condition in the Choke Mountain, northwestern Ethiopia.

  7. Propagation Techniques for Highland Bamboo (Arundinaria alpina ...

    African Journals Online (AJOL)

    Regional State) and Enjibara (Awi Zone, Amhara) communities indicated that A. alpina is an important part of the ... East Gojam Administrative Zone of Amhara National Regional State. The site is located 330 km .... of identifying whether a propaguel is dead or not, and so as avoid disturbance on buried propaguels at 2 and ...

  8. Genome characterization of the oleaginous fungus Mortierella alpina.

    Directory of Open Access Journals (Sweden)

    Lei Wang

    Full Text Available Mortierella alpina is an oleaginous fungus which can produce lipids accounting for up to 50% of its dry weight in the form of triacylglycerols. It is used commercially for the production of arachidonic acid. Using a combination of high throughput sequencing and lipid profiling, we have assembled the M. alpina genome, mapped its lipogenesis pathway and determined its major lipid species. The 38.38 Mb M. alpina genome shows a high degree of gene duplications. Approximately 50% of its 12,796 gene models, and 60% of genes in the predicted lipogenesis pathway, belong to multigene families. Notably, M. alpina has 18 lipase genes, of which 11 contain the class 2 lipase domain and may share a similar function. M. alpina's fatty acid synthase is a single polypeptide containing all of the catalytic domains required for fatty acid synthesis from acetyl-CoA and malonyl-CoA, whereas in many fungi this enzyme is comprised of two polypeptides. Major lipids were profiled to confirm the products predicted in the lipogenesis pathway. M. alpina produces a complex mixture of glycerolipids, glycerophospholipids and sphingolipids. In contrast, only two major sterol lipids, desmosterol and 24(28-methylene-cholesterol, were detected. Phylogenetic analysis based on genes involved in lipid metabolism suggests that oleaginous fungi may have acquired their lipogenic capacity during evolution after the divergence of Ascomycota, Basidiomycota, Chytridiomycota and Mucoromycota. Our study provides the first draft genome and comprehensive lipid profile for M. alpina, and lays the foundation for possible genetic engineering of M. alpina to produce higher levels and diverse contents of dietary lipids.

  9. Extension of POA based on Fiber Element to Girder Bridge

    Science.gov (United States)

    Li, Zhenxin; Qiang, Shizhong

    2010-05-01

    Because of its main advantage of simplicity, practicality, lower computational cost and relative good results Pushover analysis (POA) has become an effective analytical tool during the last decade for the seismic assessment of buildings. But such work on bridges has been very limited. Hence, the aim of this study is to adapt POA for nonlinear seismic analysis of girder bridges, and investigate its applicability in the case of an existing river-spanning approach bridge. To three different types bridge models the nonlinear POA, which adopts fiber model nonlinear beam-column element based on flexibility approach, with return period about 2500 years is carried out. It can be concluded that POA is applicable for bridges, with some shortcomings associated with the method in general, even when it is applied for buildings. Finally the applicable selection for monitoring point and lateral load pattern is suggested according to dynamic characteristic of girder bridges.

  10. HAC-POA Policy Effects on Hospitals, Patients and Other...

    Data.gov (United States)

    U.S. Department of Health & Human Services — According to findings reported in HAC-POA Policy Effects on Hospitals, Patients, and Other Payers, published in Volume 4, Issue 3 of the Medicare and Medicaid...

  11. Via GeoAlpina - an international project of IYPE

    Science.gov (United States)

    Piller, Werner E.

    2010-05-01

    Mountainous areas show earth science features in a very conspicuous, frequently even in a spectacular way. Because of the general perception of the beauty of mountains many mountainous regions are well developed in terms of trails and touristic infrastructure. Therefore, mountains are a key area to bring earth sciences closer to people. In many mountain chains all over the world (e.g., Alps, Pyrenees, Andes, Rocky Mountains) far-ranging walking and hiking trails are developed to serve a broad audience. To provide this audience with basic information in geological phenomena along such trails the project "Via Geo..." was born as an international activity within the International Year of Planet Earth. The Alps have been selected to act as a pilot project with six Alpine nations participating: Austria, France, Germany, Italy, Slovenia, and Switzerland. Many well maintained trails exist bridging the Alps from the Adriatic Sea in Trieste (Italy) to Monte Carlo (Monaco) in the Western Mediterranean. Some of these trails are included in the project "Via Alpina". The idea of Via GeoAlpina is to point at geological attractions along the trails of Via Alpina or in their vicinity and offer simple but striking information. Various earth science fields will be covered, such as geology, geophysics, paleontology, mineralogy, hydrogeology, pedology, climatology, and geomorphology. The trail descriptions can be accessed and downloaded from the Via GeoAlpina website. In 2009 every country inaugurated Via GeoAlpina on a national base with a particular opening event in the presence of local authorities and local and national media. These events were accompanied with the distribution of flyers, by offering guided tours and by installation of panels in the field. These activities, however, should be followed by even more actions in the following years. These follow-ups should attract local and regional authorities at state, county or village level and will ideally be financed by private

  12. Seed germination of five Poa species at negative water potentials

    Science.gov (United States)

    Under field conditions water is often inadequate for satisfactory seed germination. An experiment was conducted to determine the effects of simulated dry conditions on germination and seedling growth of five bluegrass (Poa) species including: Texas, P. arachnifera Torr.; annual, P. annua L.; mutto...

  13. Airflow patterns in a small subalpine basin

    Science.gov (United States)

    G. Wooldridge; R. Musselman; B. Connell; D. Fox

    1992-01-01

    A study of mean wind speeds and directions has been completed in the Snowy Range of Southern Wyoming, U.S.A. It was conducted in a subalpine ecosystem at an altitude of 3 200 m to 3 400 m above sea level during the summers of 1988 and 1989. Indexes of deformation and axes of asymmetry due to wind shaping of Engelmann spruce (Picea engelmannii) and subalpine fir (Abies...

  14. A Survey of Apomixis and Ploidy Levels Among Poa L. (Poaceae) Using Flow Cytometry

    Science.gov (United States)

    Poa, commonly known as bluegrass, includes over 500 species of which at least 40 have agronomic importance. Poa is complex, both in reproductive mode and genetics, with many species apomictic and highly variable in chromosome number. In order to more efficiently develop improved varieties of Poa, ...

  15. Assessment of Poa annua resistance to clethodim in Costa Rica.

    OpenAIRE

    Ana María Rodríguez-Ruiz; Néstor Chaves-Barrantes; Alberto Hernández-Díaz; Franklin Herrera-Murillo

    2015-01-01

    The objective of this study was to check for the presence of resistance to clethodim in Poa annua populations observed in onion fields in the highlands of Cartago, Costa Rica. Two experiments were conducted; the first one was carried out, in 2007, in a greenhouse at the Fabio Baudrit Moreno Agricultural Experiment Station (EEAFBM, in Spanish), with seeds of plants from a farm where clethodim exercised good control (S population), and from another farm where clethodim showed a deficient contro...

  16. Ice nucleation activity in the widespread soil fungus Mortierella alpina

    Science.gov (United States)

    Fröhlich-Nowoisky, Janine; Hill, Thomas C. J.; Pummer, Bernhard G.; Yordanova, Petya; Franc, Gary D.; Pöschl, Ulrich

    2015-04-01

    Biological residues in soil dust are a potentially strong source of atmospheric ice nucleators (IN). However, the sources and characteristics of biological - in particular, fungal - IN in soil dust have not been characterized. By analysis of the culturable fungi in topsoils, from a range of different land use and ecosystem types in south-east Wyoming, we found ice nucleation active (INA, i.e., inducing ice formation in the probed range of temperature and concentration) fungi to be both widespread and abundant, particularly in soils with recent inputs of decomposable organic matter. For example, in harvested and ploughed sugar beet and potato fields, and in the organic horizon beneath Lodgepole pine forest, their relative abundances and concentrations among the cultivable fungi were 25% (8 x 103 CFU g-1), 17% (4.8 x 103 CFU g-1) and 17% (4 x 103 CFU g-1), respectively. Across all investigated soils, 8% (2.9 x 103 CFU g-1) of fungal isolates were INA. All INA isolates initiated freezing at -5° C to -6° C and all belonged to a single zygomycotic species, Mortierella alpina (Mortierellales, Mortierellomycotina). By contrast, the handful of fungal species so far reported as INA all belong within the Ascomycota or Basidiomycota phyla. Mortierella alpina is known to be saprobic (utilizing non-living organic matter), widespread in soil and present in air and rain. Sequencing of the ITS region and the gene for γ-linolenic elongase revealed four distinct clades, affiliated to different soil types. The IN produced by M. alpina seem to be extracellular proteins of 100-300 kDa in size which are not anchored in the fungal cell wall. Ice nucleating fungal mycelium will ramify topsoils and probably also release cell-free IN into it. If these IN survive decomposition or are adsorbed onto mineral surfaces, these small cell-free IN might contribute to the as yet uncharacterized pool of atmospheric IN released by soils as dusts.

  17. Iridoid glucosides in Plantago alpina and P. altissima

    DEFF Research Database (Denmark)

    Jensen, Søren Rosendal; Olsen, Carl Erik; Rahn, Knud

    1996-01-01

    Two species of Plantago, namely P. Alpina and P. altissima were investigated. From the former, nine iridoid glucosides and verbascoside were isolated. Together with the known iridoids gardoside, geniposidic acid, 8-epi-loganic acid, mussaenosidic acid, aucubin, monomelittoside and melittoside, two...... new glucosides were found: 10-O-acetylgeniposidic acid and alpinoside, another compound with a 10-O-acetyl group. From P. altissima verbascoside and isoverbascoside were isolated together with the known iridoids gardoside, 8-epi-loganic acid, catalpol, aucubin, and hookerioside as well as the new...

  18. Via GeoAlpina - an international project of IYPE (Invited)

    Science.gov (United States)

    Piller, W. E.

    2009-12-01

    Mountainous areas show geological features in a very conspicuous, frequently even in a spectacular way. Because of the general perception of the beauty of mountains many mountainous regions are well developed in terms of touristic infrastructure and accessibility. Therefore, mountains are a key area to bring earth sciences closer to people. In many mountain chains all over the world (e.g., Alps, Pyrenees, Andes, Rocky Mountains, Himalayas) far-ranging walking and hiking trails are developed to serve a broad spectrum of activists. To supply this audience with basic information about geological phenomena and processes along such trails the project “Via Geo...” was born as an international activity within the International Year of Planet Earth. This approach may and should be applied in different parts of the world. The Alps have been selected to act in a pilot project with six Alpine nations participating in “Via GeoAlpina”: Austria, France, Germany, Italy, Slovenia, and Switzerland. This is due to the fact that a wealth of well maintained trails and touristic infrastructure exists all over the Alps. Some of these are included in the project “Via Alpina” bridging the entire mountain system from the Adriatic Sea at Trieste (Italy) to Monte Carlo (Monaco) in the Western Mediterranean. The idea of Via GeoAlpina is to point at geological attractions along the trails of Via Alpina or in their vicinity and to offer simple but clear-cut information on these features. Various earth science fields will be covered, such as geology, geophysics, paleontology, mineralogy, hydrogeology, pedology, climatology, and geomorphology. In addition, particular topics on applied earth science aspects, e.g, mineral recourses and geological hazards, which are of particular importance for society, will be addressed. This information is primarily web-based and trail descriptions can be accessed and downloaded from the Via GeoAlpina website (http://www.viageoalpina.org). In 2009

  19. Mapping of epitopes on Poa p I and Lol p I allergens with monoclonal antibodies.

    Science.gov (United States)

    Lin, Z W; Ekramoddoullah, A K; Jaggi, K S; Dzuba-Fischer, J; Rector, E; Kisil, F T

    1990-01-01

    Allergen Poa p I isolated from the dialysed aqueous extract of Kentucky blue grass pollen by affinity chromatography with an anti-Lol p I murine monoclonal antibody (MAb) 290A-167 was previously shown to consist of a 35.8-kilodalton (kD) component with a pI of 6.4, designated as Poa p Ia, and a 33-kD component with a pI of 9.1, designated as Poa p Ib. The present study reports on the comparative antigenic analyses of these two components, using MAbs produced separately against Poa p I and Lol p I. Thus, anti-Poa p I MAbs 60 and 61 and anti-Lol p I MAb 290A-167 recognized Poa p Ia and Poa p Ib whereas anti-Poa p I MAbs 62, 63 and 64 and anti-Lol p I MAb 348A-6 recognized only Poa p Ia. The specificities of the MAbs were further resolved by comparing their respective abilities to inhibit the binding of 125I-Poa p I or 125I-Lol p I to the different MAbs prepared in the form of solid phase. These studies revealed that at least 4 distinct epitopes (designated as E1, E2, E3 and E4) were shared by both Poa p I and Lol p I. All 4 epitopes were present on Poa p Ia whereas only E1 and E3 were detected on Poa p Ib. E1 was recognized by MAbs 60 and 61, E2 by MAbs 62, 63 and 64, E3 by MAb 290A-167 and E4 by MAb 348A-6.(ABSTRACT TRUNCATED AT 250 WORDS)

  20. Alpina: Innovación permanente para «sorprender» al cliente

    Directory of Open Access Journals (Sweden)

    Mauricio Nieto Potes

    2006-07-01

    Full Text Available Proceso llevado a cabo por ALPINA en el desarrollo de nuevos productos, incluyendo estudios de mercado y marketing, estudios de factibilidad técnica y la coherencia del producto con el enfoque de la empresa.

  1. On the occurrence of sonchuside A in Cicerbita alpina and its chemosystematic significance

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    HERMANN STUPPNER

    2005-02-01

    Full Text Available The subaerial parts of Cicerbita alpina yielded the guaianolide 8-acetyl-15b-D-glucopyranosyllactucin (1 and the germacranolide Sonchuside A (2. The sonchuside A is reported for the first time from the genus Cicerbita. 1H-NMR and 13C NMR data of compounds 1 and 2 measured in deuterodimethyl sulfoxide and deuteromethanol, respectively, are given and the chemosystematic implications of the occurrence of sonchuside A in C. alpina are discussed briefly.

  2. Arachidonic acid production by Mortierella alpina using raw crop materials.

    Science.gov (United States)

    Cao, Ganggang; Guan, Zhengbing; Liu, Feixian G; Liao, Xiangru; Cai, Yujie

    2015-01-01

    Arachidonic acid (ARA) is one of the three essential fatty acids, and it is important for human body to keep healthy and is widely used. At present, expensive materials such as glucose and yeast extract are generally reported to be optimal for ARA production. A new cost-effective fermentation process including cheaper material for ARA production is of great significance. Feasibility of using corn meal and powdered soybean for fungal growth and lipid accumulation was evaluated by means of single factor test. N-hexadecane concentration was optimized, and the effect of temperature on biomass and ARA content was examined. Mortierella alpina made better use of the aforementioned material as carbon and nitrogen sources for both hyphae growth and ARA production compared with glucose and yeast extract. Maximal levels of 10.9 g/L ARA and 26.1 g/L total lipids were obtained when 66 g/L corn meal, 54 g/L soybean meal and 6% (v/v) n-hexadecane were supplemented. A temperature-shift strategy involved three steps, namely, 30°C (3 days) - 25°C (4 days) - 20°C (4 days), which further improved ARA production by 24.7%. Several factors such as carbon and nitrogen sources, temperature and dissolved oxygen had great influence on biomass and microbial oil production. Mortierella alpina preferred corn and soybean meal compared with glucose and yeast extract, which would surely alleviate the high cost of ARA production. Based on this study, the new process is both low cost and practicable.

  3. The Influence of Low Temperature on Diel Patterns of Carbohydrate Metabolism in Leaves of Poa annua L. and Poa x jemtlandica (Almq.) Richt

    National Research Council Canada - National Science Library

    Anne M. Borland; J. F. Farrar

    1987-01-01

    The effect of low temperature on diel changes in net gas exchange, carbohydrate content and export, and on the extractable activities of sucrose phosphate synthase and acid invertase from leaves of Poa annua (a ruderal grass...

  4. Isolation of endophyic bacteria from purwoceng (Pimpinella alpina Kds.

    Directory of Open Access Journals (Sweden)

    Tri Widayat

    2012-09-01

    Full Text Available AbstrakLatar belakang: Purwoceng (Pimpinella alpina Kds. merupakan tanaman obat langka yang berkhasiat sebagai afrodisiak. Tanaman yang mengandung kumarin tersebut berinteraksi dengan bakteri endofi t. Senyawa kumarin dalam industri dimanfaatkan untuk bahan aditif makanan dan parfum. Penelitian ini bertujuan untuk mendapatkan bakteri endofi t dari tanaman purwoceng, menganalisis kemampuan tumbuh bakteri endofi t dalam medium yang mengandung kumarin, dan pengaruh bakteri tersebut terhadap jumlah kumarin dalam medium pertumbuhan.Metode: Isolasi bakteri endofi t dilakukan secara langsung dari akar dan daun purwoceng. Seleksi bakteri endofi t penghasil kumarin dilakukan berdasarkan kemampuan bertahan hidup pada medium cair ammoniumsalt sugar (ASS yang mengandung infusa herba purwoceng. Pengaruh bakteri terhadap jumlah kumarin di dalam medium pertumbuhan diuji melalui percobaan kultivasi isolat bakteri terpilih pada medium yang sama. Jumlah kumarin dalam kultur dideteksi menggunakan teknik kromatografi lapis tipis (KLT.Hasil: Sembilan isolat bakteri endofi t yang berhasil diisolasi dari akar dan daun tanaman purwoceng mampu bertahan hidup pada medium basal yang diberi infusa herba purwoceng dengan waktu generasi (g 2,7-5,07jam dan kecepatan pertumbuhan spesifi k (μ 0,14-0,26/jam. Kultivasi isolat terpilih menunjukkan bahwa BAP5 menghasilkan senyawa dengan Rf 0,27 yang diduga sebagai turunan kumarin. Bakteri BAP5 mampu tumbuh dengan jumlah kumarin 1072 arbitrary unit (AU dalam medium.Kesimpulan: Bakteri endofi t dapat diisolasi dari tanaman purwoceng dan secara in vitro mampu mempertahankan jumlah kumarin yang terkandung di dalam medium. (Health Science Indones 2012;1:31-6Kata kunci: bakteri endofi t, purwoceng, Pimpinella alpina Kds, kumarinAbstractBackground: Purwoceng (Pimpinella alpina Kds. is a medicinal plant species used as aphrodisiac. Like any other plants, the coumarin containing plant probably interacts with endophytic bacteria. Coumarin

  5. Floristic and community diversity of sub-alpine and alpine grasslands and grazed dwarf-shrub heaths in the Romanian Carpathians

    Directory of Open Access Journals (Sweden)

    Coldea, Gheorghe

    1998-12-01

    Full Text Available Floristic diversity at community level and community diversity at landscape level are presented for the main grassland and dwarf-shrub communities in the sub-alpine and alpine zones in five mountain ranges of the Romanian Carpathians. The 30 plant communities studied had their floristic composition and distribution determined by geological substratum and pedo-climatic factors. The most diverse grasslands (Oxytropido-Elynetum, Seslerio haynaldianae-Caricetun were on calcareous substratum and on the mountain slopes (Festucetum pictae, whilst the lowest diversity was in the oligo-mesotrophic sub-alpine grasslands (Scorzonero- Festucetum nigricantis, Alchemillo-Poetum alpinae, Violo-Nardetum. The Shannon-Weaver diversity index for the communities increased almost linearly with the number of species per community, whilst community diversity in the five mountain ranges was a function of the number of communities per mountain range.

    [fr] Nous présentons dans ce travail la diversité floristique au niveau de la communauté et la diversité de communautés au niveau du paysage pour les principaux types de pâturages et de communautés à petits arbustes des étages subalpin et alpin de cinq chaînes montagneuses des Carpathes en Roumanie. Aussi bien la composition floristique que la distribution des 30 communautés étudiées dépendent de la nature géologique du terrain et des facteurs édapho-climatiques. Les pâturages les plus riches en diversité (Oxytropido-Elynetum, Seslerio haynaldianae- Caricetun se développent sur substrat calcaire et sur les versants des montagnes (Testucetum pictae; par contre la plus faible diversité a été rencontrée dans les pâturages oligo-mesotrophes subalpins (Scorzonero-Festucetum nigricantis, Alchemillo-Poetum alpinae, Violo-Nardetum. L'index de diversité de Shannon- Weaver augmente quasi linéairement avec le nombre d'espèces de chaque communauté, tandis que

  6. Virulence of Xanthomonas translucens pv. poae Isolated from Poa annua

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    Arielle Chaves

    2013-03-01

    Full Text Available Bacterial wilt is a vascular wilt disease caused by Xanthomonas translucens pv. poae that infects Poa annua, a grass that is commonly found on golf course greens throughout the world. Bacterial wilt causes symptoms of etiolation, wilting, and foliar necrosis. The damage is most prevalent during the summer and the pathogen can kill turf under conditions optimal for disease development. Fifteen isolates of X. translucens pv. poae were collected from northern regions in the United States and tested for virulence against P. annua. All 15 isolates were pathogenic on P. annua, but demonstrated variable levels of virulence when inoculated onto P. annua under greenhouse conditions. The isolates were divided into two virulence groups. The first group containing four isolates generally resulted in less than 40% mortality following inoculation. The second group, containing the other eleven isolates, produced between 90 and 100% mortality following inoculation. These results suggest that differences in the virulence of bacterial populations present on a golf course may result in more or less severe amounts of observed disease.

  7. Cytoarchitectonic analysis of the SDN-POA of the intact and gonadectomized rat.

    Science.gov (United States)

    Bloch, G J; Gorski, R A

    1988-09-22

    The densely staining group of cells referred to as the sexually dimorphic nucleus of the preoptic area (SDN-POA) is greater in volume in the male than in the female rat. Because we and others have reported absolute volumes that have been consistent within individual studies but that vary considerably, we characterized the SDN-POA by describing its morphology with respect to the cytoarchitectonic divisions of the medial preoptic nucleus (MPN) in intact and gonadectomized rats. We report three major findings: the SDN-POA is heterogeneous and is composed of cells belonging to three distinct cytoarchitectonic divisions; the cytoarchitecture of the MPN and its medial and lateral divisions (MPNm and MPNl, respectively) in male rats appear to be influenced by the hormonal status in adulthood; and a small anteroventral division of the MPN (MPNav) is present in males but virtually absent in females. Specifically, the SDN-POA is located within the MPNm, but consists of subcomponents located within the central division of the MPN (MPNc), the MPNav, and part of the MPNm-exclusive of the MPNc and MPNav. The percentage of the total SDN-POA located within the MPNc and MPNav. The percentage of the total SDN-POA located within the MPNc and MPNav was greater in males, and that in the MPNm-exclusive of the MPNc and MPNav was greater in females, indicating that the SDN-POA has a different cytoarchitectonic composition in the two sexes. Gonadectomy produced no significant differences in SDN-POA volume, but the MPN, MPNl, and MPNm were significantly reduced in gonadectomized versus intact males, suggesting an activational effect of testicular hormones on these structures.

  8. Alpina: un caso de innovación para la competitividad

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    Juan Pablo Fernández González

    2013-08-01

    Full Text Available Alpina es una compañía pionera en la industria de alimentos en Colombia que se ha desarrollado a partir de la innovación. Este artículo presenta cómo Alpina ha forjado una cultura de innovación, calidad y emprendimiento en todo lo que realiza y cómo los constantes cambios en el contexto competitivo motivan el desarrollo continuo de la capacidad de innovación y estrategias para hacer el negocio más sostenible y con proyección hacia el futuro.

  9. Distribution and habitats of Chamorchis alpina (L. Rich. (Orchidaceae in Poland

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    Halina Piękoś-Mirkowa

    2014-01-01

    Full Text Available Chamtorchis alpina (L. Rich. is a rare high mountain species occurring in Poland exclusively in the Tatra Mts. Its distribution presented on the map and altitudinal range are based on the authors' own material collected in the field as well as on literature data supplemented by herbarium records. The orographic and edaphic factors as well as phytocoenoses in which the species occurs are characterised. Moreover, information on size of the Tatra populations is given and the threat category for Ch. alpina in Poland is discussed.

  10. An improved sampling protocol for analysis of intracellular metabolites in Mortierella alpina.

    Science.gov (United States)

    Liu, Xin; Zhang, Hongman; Ji, Xiaojun; Zheng, Hongbo; Zhang, Xin; Fu, Ninghua; Huang, He

    2012-12-01

    Sampling of intracellular metabolites in Mortierella alpina was investigated as part of a metabolomics study. After comparison of four sampling protocols, rapid filtration of the culture using a laboratory-made nylon filter and absorbent gauze under normal pressure followed by quenching in liquid N(2) and grinding (the improved protocol) was the most effective. Rapid filtration under normal pressure decreased intracellular metabolites leakage and subsequent grinding of cells contributed to intracellular metabolites extraction. The above quenching method together with 75 % (v/v) ethanol, buffered with 60 mM HEPES, at 80 °C for 3 min is therefore suitable for sampling intracellular metabolites in M. alpina.

  11. Assessment of Poa annua resistance to clethodim in Costa Rica.

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    Ana María Rodríguez-Ruiz

    2015-06-01

    Full Text Available The objective of this study was to check for the presence of resistance to clethodim in Poa annua populations observed in onion fields in the highlands of Cartago, Costa Rica. Two experiments were conducted; the first one was carried out, in 2007, in a greenhouse at the Fabio Baudrit Moreno Agricultural Experiment Station (EEAFBM, in Spanish, with seeds of plants from a farm where clethodim exercised good control (S population, and from another farm where clethodim showed a deficient control (R population. Both S and R populations were treated with different doses of clethodim (0.5X, 1.0X, 1.5X and 2.0X, being X the recommended commercial dose. In this experiment, control of the R population was 44% and 17% at doses of 1.5X and 2.0X, respectively, whereas control of the S population was 100% at either of those doses. The second experiment was carried out in 2009, seeds of two other P. annua populations were collected in a similar way: one population from an area where weed control was satisfactory (S, and the other population from an area of the farm where control was deficient (R. Seeds were sown, depending on the type, in plastic pots and sprayed with clethodim at doses of: 0. 1X, 2X, 4X, 8X, and 16X. There were significant differences in the reactions to clethodim of both P. annua populations The S population showed a higher percentage of control and less surviving plants than the R population. Several plants of the R population resisted up to 16X commercial doses of clethodim. Results of both experiments suggest the presence of P. annua populations resistant to clethodim.

  12. An influence of abiotic factors on the germinability of Agrostis species and Poa species

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    Pavel Knot

    2006-01-01

    Full Text Available The objective of this contribution is to interpret the impact of some abiotic factors on the germinability. Primarily was observed the stress that they cause on germinability and also on the energy of other perennial grass caryopsis' germinability. Withal there were considered differences in germinability of some perennial grass species, variances of strains and the influence of today`s seeds dressing technologies, which are used to improve the germination. The light factor has the biggest influence of all factors on germination of Agrostis stolonifera (Penn G-2, Providence, Poa supina (Supranova and Poa pratensis (Julius, Julius PreGerm. All these species had germination evidential higher in the light, than in the dark. With species Poa pratensis (Coctail, Coctail Headstart and Poa annua were not observed any essential variations between the dark and the light variants. Only with Poa annua there were reached noticeably lower values with variant in the light, where was used polyethyleneglycol, than in the dark. The analysis of variance demonstrated, that the biggest influence had the factor of stratification together with the light factor with Agrostis capilaris (Bardot and Agrostis stolonifera Providence. With Poa annua there was established the biggest influence of the light factor together with the factor of the used medium. The factor of stratification noticeably affected only the germination of Agrostis capillaris Bardot. The germination of Agrostis stolonifera Providence, Poa pratensis Cocktail, Cocktail Headstart, Julius and Poa annua was not noticeably affected by stratification. The reaction on the factor of stratification was with Agrostis capillaris Bardot in the dark adverse and in the light minimal. Poa pratensis Julius PreGerm germination was negative in the dark as well as in the light. With Poa supina Supranova it was not the most important factor, but still affected the germination significiantly. The nitrogen nutrition, as the

  13. Expression of Vitreoscilla hemoglobin enhances production of arachidonic acid and lipids in Mortierella alpina.

    Science.gov (United States)

    Zhang, Huidan; Feng, Yingang; Cui, Qiu; Song, Xiaojin

    2017-08-30

    Arachidonic acid (ARA, C20:4, n-6), which belongs to the omega-6 series of polyunsaturated fatty acids and has a variety of biological activities, is commercially produced in Mortierella alpina. Dissolved oxygen or oxygen utilization efficiency is a critical factor for Mortierella alpina growth and arachidonic acid production in large-scale fermentation. Overexpression of the Vitreoscilla hemoglobin gene is thought to significantly increase the oxygen utilization efficiency of the cells. An optimized Vitreoscilla hemoglobin (VHb) gene was introduced into Mortierella alpina via Agrobacterium tumefaciens-mediated transformation. Compared with the parent strain, the VHb-expressing strain, termed VHb-20, grew faster under both limiting and non-limiting oxygen conditions and exhibited dramatic changes in cell morphology. Furthermore, VHb-20 produced 4- and 8-fold higher total lipid and ARA yields than those of the wild-type strain under a microaerobic environment. Furthermore, ARA production of VHb-20 was also 1.6-fold higher than that of the wild type under normal conditions. The results demonstrated that DO utilization was significantly increased by expressing the VHb gene in Mortierella alpina. The expression of VHb enhances ARA and lipid production under both lower and normal dissolved oxygen conditions. This study provides a novel strategy and an engineered strain for the cost-efficient production of ARA.

  14. Condensed Volcanic Aerosols Collected Near-Source at Poas

    Science.gov (United States)

    Pfeffer, M.; Rietmeijer, F.; Brearley, A.; Basame, S.; Fischer, T.

    2001-12-01

    Volcanic plumes are mixtures of gases and liquids that react with air to form aerosols. In this study, atmospheric samples were collected near fumarolic vents at Poas Volcano inside the crater and 380m away on the crater rim. Aerosols were captured on supportive Cu grids coated by a thin C-film, encased within a sealed collector designed for this experiment. Grids were exposed to plume constituents for 30-seconds then frozen to prevent further reaction before analysis. Morphologic and chemical features were examined by TEM, Energy Dispersive X-Ray Spectroscopy (EDS) and Atomic Force Microscopy (AFM). A thin heterogeneous coating of Si and lesser Fe with minor, variable Cl and S covers the C-film. Solid particles additionally contain O and Mg. Liquid droplets of splattered appearance containing Na, Mg and O, lesser amounts of K, Ca and Cl, and minor S and Fe, are surrounded by satellite droplets and radially symmetrical dendritic patterns. Varied components in single droplets suggest that near source, liquids are not necessarily differentiated. O found in particles and droplets but not in the coating may demonstrate partitioning of O out of the condensable gaseous phase. These two observations show that differentiation has begun, but is not completed, at short distances from source. Liquid droplets of varying heights (15-35nm) and diameters (300-500nm) are topped with smaller (5nm high; 50nm diameter) domes. A mottled surface covers morphological highs and flat areas. Contraction marks that grew wider as analysis progressed extend between and linearly across the surface of the droplets. Different size droplets could represent fluids of differing surface tensions growing to individually preferential size, or droplets that have not achieved ideal size. Smaller domes atop larger ones may be gases escaping. These samples represent a portion of volcanic plumes that must be studied to understand the evolution of volcanic aerosols, and, consequently, their influence on

  15. Lesions of the SDN-POA inhibit sexual behavior of male Wistar rats.

    Science.gov (United States)

    De Jonge, F H; Louwerse, A L; Ooms, M P; Evers, P; Endert, E; van de Poll, N E

    1989-12-01

    Discrete bilateral lesions in the SDN-POA of sexually naive adult male rats were found to decrease the number of animals ejaculating and/or to increase latencies to the first mount, intromission and ejaculation. The deleterious effects of the lesions disappeared after 4 tests for sexual behavior but were reinstated when the males were tested under suboptimal conditions, i.e., when they were tested with a marginally receptive female or when they had only limited access to the stimulus female. It was subsequently shown that males with a bilaterally lesioned SDN-POA still showed an increase in plasma testosterone. LH and prolactin levels in response to sexual stimulation. Effects of the lesions on scent marking were not found. Together with previous data indicating that SDN-POA-lesions disrupt masculine sexual behavior in females, these data are taken as evidence that the SDN-POA plays a role in the regulation of masculine sexual behavior. The data further suggest that previously reported negative results of SDN-POA-lesions on masculine sexual behavior in male rats might be attributed to the use of sexually experienced instead of sexually inexperienced animals.

  16. THE INITIAL GROWTH AND DEVELOPMENT OF POA PRATENSIS UNDER THE ALLELOPATHIC INFLUENCE OF TARAXACUM OFFICINALE

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    Kazimierz Jankowski

    2014-04-01

    Full Text Available This experiment was carried out in laboratory conditions. The aim of this work was estimating allelopathic potential of Taraxacum officinale on seeds germination and initial growth of Poa pratensis. In the experiment different concentration of soil’s and plant’s water solution obtained from common dandelion were employed. The inhibition of germination energy of Poa pratensis under the influence of plant extracts produced from roots and leaves of Taraxacum officinale was found. Germination availability was inhibited in a higher degree by extracts prepared from the leaves than the roots of Taraxacum officinale. Higher concentrations of all solutions of both the soil and the plant inhibited the length of seending of Poa pratensis.

  17. Unsupervised component analysis: PCA, POA and ICA data exploring - connecting the dots

    Science.gov (United States)

    Pereira, Jorge Costa; Azevedo, Julio Cesar R.; Knapik, Heloise G.; Burrows, Hugh Douglas

    2016-08-01

    Under controlled conditions, each compound presents a specific spectral activity. Based on this assumption, this article discusses Principal Component Analysis (PCA), Principal Object Analysis (POA) and Independent Component Analysis (ICA) algorithms and some decision criteria in order to obtain unequivocal information on the number of active spectral components present in a certain aquatic system. The POA algorithm was shown to be a very robust unsupervised object-oriented exploratory data analysis, proven to be successful in correctly determining the number of independent components present in a given spectral dataset. In this work we found that POA combined with ICA is a robust and accurate unsupervised method to retrieve maximal spectral information (the number of components, respective signal sources and their contributions).

  18. Germination Ecology of Arundinaria alpina (K. Schum. and Oxytenanthera abyssinica (A. Rich. Munro Seeds: Indigenous Bamboo Species in Ethiopia

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    Tinsae Bahru

    2015-01-01

    Full Text Available Highland bamboo (Arundinaria alpina and lowland bamboo (Oxytenanthera abyssinica are indigenous to Ethiopia and endemic to Africa. Seeds of A. alpina were collected from Dawa Wereda (District, while O. abyssinica seeds were collected from Pawe and Sherkole Weredas. In this study, seed presowing treatments, effects of dry heat, moist heat, and light/dark treatments on the germination of seeds were tested. The averages were of 59,416 and 8,393 seeds contained within 1 kg of A. alpina and O. abyssinica seeds within 86 and 91% pure seeds, respectively. From 1 kg of pure seeds 37,301 and 7,168 seedlings are raised in the laboratory in their respective orders. The result revealed that control seeds of A. alpina and O. abyssinica showed the best germination of 73 and 98%. Germination of both dry and moist heat treatments of O. abyssinica seeds was significantly improved at 60 and 80°C. Unlike A. alpina seeds, seeds of O. abyssinica had better germination for light treatment compared to dark. For effective large scale plantation and raising of A. alpina and O. abyssinica seedlings from its seeds for laboratory, control seeds supply to necessary light source (for O. abyssinica seeds is recommended.

  19. SDN-POA volume, sexual behavior, and partner preference of male rats affected by perinatal treatment with ATD

    NARCIS (Netherlands)

    E.J. Houtsmuller (Elisabeth Judith); T. Brand (Teus); F.H. de Jonge (F.); R.N.J.M.A. Joosten (R. N J M A); N.E. van de Poll (N.); A.K. Slob (Koos)

    1994-01-01

    textabstractThe present study investigated 1) the importance of the aromatization process during the perinatal period for the development of the sexually dimorphic nucleus in the preoptic area of the hypothalamus (SDN-POA) of male rats, and 2) the relationship between SDN-POA volume and parameters

  20. Using functional traits to assess the resistance of subalpine grassland to trampling by mountain biking and hiking.

    Science.gov (United States)

    Pickering, Catherine Marina; Barros, Agustina

    2015-12-01

    Functional traits reflect plant responses to disturbance, including from visitor impacts. The impacts of mountain biking and hiking on functional composition were compared using a common experimental protocol in a subalpine grassland in the Australian Alps. The overlapping cover of all species was recorded two weeks after different intensities of hiking (200 and 500 passes) and mountain biking (none, 25, 75, 200 and 500 passes). Species' functional trait data were combined with their relative cover to calculate community trait weighted means for plant height, leaf area, percentage leaf dry matter content and Specific Leaf Area (SLA). Species such as Poa fawcettiae with larger leaves and SLA but lower dry weight content of leaves were more resistant to use, with differences between bikers and hikers only apparent at the highest levels of use tested. This differs from some vegetation communities in Europe where plants with smaller leaves were more resistant to hiking. More research using functional traits may account for differences in species responses to trampling. Managers of conservation areas used for hiking and biking need to minimise off trail use by both user groups. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. The influence of goose grazing on the growth of Poa arctica : overestimation of overcompensation

    NARCIS (Netherlands)

    Loonen, MJJE

    The effect of grazing by barnacle geese (Branta leucopsis) on above-ground production was investigated on the Arctic tundra grass Poa arctica at Spitsbergen during the growing season of 1996. We applied three treatments: orated; whole season ungrazed and temporary ungrazed during the second half of

  2. Development of turf-type Poa pratensis l. germplasm for seed production without field burning

    Science.gov (United States)

    Open-field burning of Kentucky bluegrass (Poa pratensis L.) post- harvest residue, which maintains grass seed yield and stand longevity, has been eliminated in Washington and is restricted in Idaho and Oregon, USA. Our objective was to develop Kentucky bluegrass germplasm that has sustainable seed y...

  3. DNA contents in Texas bluegrass (Poa arachnifera) selected in Texas and Oklahoma determined by flow cytometry

    Science.gov (United States)

    Texas bluegrass (Poa arachnifera Torr.) is a dioecious, perennial, cool-season grass native to southern Kansas, Oklahoma, western Arkansas and most of Texas. Its major use has been for forage on rangelands in Texas and Oklahoma. More recently, interspecific hybrids between Texas bluegrass and Kentuc...

  4. AFLP fingerprinting of Kentucky bluegrass (Poa pratensis L.) from undisturbed Dutch grasslands: implications for conservation

    NARCIS (Netherlands)

    Treuren, van R.

    2008-01-01

    Undisturbed grasslands are considered rich sources of promising genotypes for the development of new varieties of Kentucky bluegrass (Poa pratensis L.). Grasslands that have not been resown with commercial cultivars nor treated with high doses of nitrogen fertilizer have become rare in the

  5. [Effects of aromatase inhibitor on sexual differentiation of SDN-POA in rats].

    Science.gov (United States)

    Ohe, E

    1994-03-01

    The sexually dimorphic nucleus of the preoptic area (SDN-POA) of male rats is larger than that of females, the difference being caused by the perinatal effect of estrogen converted from androgen. To investigate the role of estrogen formation in the SDN-POA during the critical period of this sexual differentiation, CGS16949A (0.5 mg/kg, sc) was injected into the mothers in the late gestational age(F) or into neonates for 14 days from birth(N). Animals were sacrificed on the 20th. day of gestation and 7 days after birth, and fetal and neonatal brain aromatase activities (AA) as well as serum levels of testosterone(T) and corticosterone(B) were measured. On the 30th day after birth, the offspring of treated mothers and neonatally treated rats were sacrificed and the cross-sectional areas of the SDN-POA were evaluated by image processor NEXUS 6800. In group F, CGS16949A markedly suppressed brain AA in vitro (fetal hypothalamus: IC50 1.4nM) and in vivo in both the hypothalamus and amygdala. However, the levels of T and B did not show any significant change in group F. The same depression of AA was also observed in group N on the 7th day after birth. In CGS-treated males in groups F and N, the SDN-POA area markedly decreased to that of control females. The area in males in group F was not significantly different from that in females. These results suggest that estrogen converted from androgen plays a dominant role in the development of sexual dimorphism of the SDN-POA, and that the brain AA in the pre- and postnatal period is important in this process.

  6. Two-dimensional gel electrophoretic analyses of Kentucky bluegrass and rye grass pollen allergens. Detection with a murine monoclonal anti-Poa p I antibody and amino terminal amino acid sequence of Poa p I allergen.

    Science.gov (United States)

    Ekramoddoullah, A K

    1990-01-01

    Allergenic extracts of Kentucky bluegrass (Poa pratensis) and rye grass (Lolium perenne) pollen were shown by 2-dimensional (2-D) gel electrophoresis to consist of several hundred protein components. The pollen extracts of the two related grasses had unique 2-D gel patterns. Two major grass pollen allergens, Poa p I and Lol p I, and their isoforms (i.e. isoallergens) were detected and localized on 2-D gels by immunoblotting with anti-Poa p I antibody mAb 60. Poa p I isoallergens were less acidic than Lol p I isoallergens. The relative proportion of four Poa p I isoallergens was (in decreasing pI): A, 13%; B, 37%; and D, 15%. The amino terminal amino acid sequences of the two major isoallergens of Poa p I were identical. However, the amino acid composition of these isoallergens showed enough differences to account for their charge differences. The amino terminal amino acid sequence of two major Poa p I isoallergens had a 70% homology in 20 amino acid overlap with the previously published amino terminal amino acid sequence of rye grass pollen allergen R-7.

  7. Quantifiable differences between phytolith assemblages detected at species level: analysis of the leaves of nine Poa species (Poaceae

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    Zsuzsa Lisztes-Szabó

    2015-10-01

    Full Text Available The taxonomic value of phytolith assemblages and their degree of variability within different species of the same genus is still an undervalued issue in the botanical range of phytolith studies. However the understanding of grass phytolith variance and its implications to plant systematics is doubtless. In the present study phytoliths of the lateral shoots (leaves of nine, globally distributed Poa species (Pooideae – Poaceae are described. Phytoliths were recovered from Poa specimens by the dry ashing technique. Altogether 6223 disarticulated phytoliths were counted (approximately 500–700 phytoliths per species in 54 plant samples, which cover six shoots of nine species. Not only the relative frequency of each morphotype was calculated, but measurements were conducted to determine the biogenic silica content of Poa lateral shoots. A phytolith reference collection for the nine selected species of a worldwide importance was also compiled. The description of the most significant phytolith morphotypes and their taxonomic relationships are given here. Results suggest that the biogenic silica content of the Poa lateral shoots was determined to be relatively high within all nine species. Phytolith assemblage data was subjected to multivariate statistical analyses (e.g., CA and PCA in order to find differences and similarities among the nine Poa species. Results show that the two closely related Poa of the P. pratensis species group, namely the P. pratensis and P. angustifolia, only slightly differ from the other Poa species if we consider their rondel-trapeziform short cells (SC phytolith frequencies.

  8. COMPORTAMIENTO FRACTAL DEL REPERTORIO T ESPECÍFICO CONTRA EL ALERGENO Poa p9 Fractal behavior of T specify repertory against Poa p9 alergeno

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    Javier Rodríguez Velásquez

    2005-04-01

    Full Text Available Antecedentes: basados en una analogía lingüística aplicada al repertorio inmune B y T específicos, el sistema inmune se puede caracterizar por su grado de complejidad como se hace con los lenguajes naturales. Material y métodos: este estudio es la aplicación de una ley matemática al repertorio inmune. Se aplicó la ley de Zipf-Mandelbrot, observada en los lenguajes naturales, al estudio del repertorio T específico contra el alergeno Poa p9. Resultados: se observó un comportamiento a escala de la ley en el repertorio específico para el alergeno obtenido de un paciente alérgico en presencia y ausencia de interferón á, y en los clones de células Th. Los repertorios T en presencia y ausencia de interferón á se comportanfractalmente, con una dimensión fractal de 0.661165 y 0.923895 respectivamente. Conclusión: el grado de complejidad del repertorio T contra el alergeno Poa p9 es una medida matemática objetiva y reproducible del repertorio inmune, la dimensión fractal es un parámetro matemático apropiado para caracterizar la fisiología del sistema inmune. Este comportamiento fractal puede tener implicaciones generales para la inmunología.Background: based on a linguistic analogy applied to the immune specific B and T repertoires the immune system it has been characterized by the degree of fractal complexity like the one observed in the natural languages. Material and methods: this study is the application of a mathematical law to the immune repertoire. The Zipf-Mandelbrot law, observed in the natural languages, was applied to the study of the specific T repertoire against the allergen Poa p9. Results: the scale behavior of the law was observed in the specific repertoire from an allergic patient, with a without alfa interferon, like in Th cells clones. Conclusion: complexity degree of T repertoire against Poa p9 allergen can be identified by fractal dimension, as a appropriate mathematical parameter to characterize the

  9. Provenance variability in nursery growth of subalpine fir

    Science.gov (United States)

    Charlie Cartwright; Cheng Ying

    2011-01-01

    Subalpine fir (Abies lasiocarpa [Hook] Nutt.) is a wide-ranging, high-elevation species in the interior of British Columbia. It is commonly harvested for lumber, but replanting of it is limited. Some reticence is based upon wood quality and rate of growth, but there are also seed and nursery culturing difficulties. This study investigated seedling growth traits of 111...

  10. Isolation of 16 Microsatellite Markers for Spiraea alpina and S. mongolica (Rosaceae of the Qinghai–Tibet Plateau

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    Gulzar Khan

    2014-01-01

    Full Text Available Premise of the study: A set of microsatellite markers were developed to characterize the level of genetic diversity and gene flow in two plant species endemic to the Qinghai–Tibet Plateau, Spiraea alpina and S. mongolica. Methods and Results: Using the Fast Isolation by AFLP of Sequences Containing repeats (FIASCO method, 16 microsatellite loci showed polymorphisms in both species. In two populations of each species, the number of alleles per locus ranged from three to 18 in S. alpina and from four to 30 in S. mongolica. Conclusions: These microsatellite markers provide an efficient tool for population genetic studies and will be used to assess the genetic diversity and spatial genetic structure of S. alpina and S. mongolica.

  11. Characterization of an fungal l-fucokinase involved in Mortierella alpina GDP-l-fucose salvage pathway.

    Science.gov (United States)

    Wang, Hongchao; Zhang, Chen; Chen, Haiqin; Yang, Qin; Zhou, Xin; Gu, Zhennan; Zhang, Hao; Chen, Wei; Chen, Yong Q

    2016-08-01

    GDP-l-fucose functions as a biological donor for fucosyltransferases, which are required for the catalysis of l-fucose to various acceptor molecules including oligosaccharides, glycoproteins and glycolipids. Mortierella alpina is one of the highest lipid-producing fungi and can biosynthesis GDP-l-fucose in the de novo pathway. Analysis of the M. alpina genome suggests that there is a gene encoding l-fucokinase (FUK) for the conversion of fucose to l-fucose-1-phosphate in the GDP-l-fucose salvage pathway, which has never been found in fungi before. This gene was characterized to explore its role in GDP-l-fucose synthesis. The yield of GDP-l-fucose is relatively higher in lipid accumulation phase (0.096 mg per g cell) than that in cell multiplication phase (0.074 mg per g cell) of M. alpina Additionally, the transcript level of FUK is up regulated by nitrogen exhaustion when M. alpina starts to accumulate lipid, highlights the functional significance of FUK in the GDP-l-fucose biosynthesis in M. alpina Gene encoding FUK was expressed heterologously in Escherichia coli and the resulting protein was purified to homogeneity. The product of FUK reaction was analyzed by liquid chromatography and mass spectrometry. Kinetic parameters and other properties of FUK were investigated. Comparative analyses between the FUK protein and other homologous proteins were performed. To our knowledge, this study is the first to report a comprehensive characterization of FUK in a fungus. Mortierella alpina could be used as an alternative source for the production of GDP-l-fucose. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  12. Development of a greenhouse-based inoculation protocol for the fungus Colletotrichum cereale pathogenic to annual bluegrass (Poa annua)

    Science.gov (United States)

    The fungus Colletotrichum cereale incites anthracnose disease on Poa annua (annual bluegrass) turfgrass. Anthracnose disease is geographically widespread highly destructive, with infections by C. cereale resulting in extensive turfgrass loss. Comprehensive research aimed at controlling turfgrass a...

  13. El éxito de la gestión ambiental en Alpina S.A.

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    Edicson Jair Gil costa Acosta

    2013-08-01

    Este análisis permitió observar tanto su excelente organización interna, como el importante desarrollo de sus políticas ambientales, las cuales se reflejan no sólo al interior de la organización, sino también al exterior, como consecuencia de su activa participación en la generación de políticas gubernamentales de alto impacto para la sociedad. Igualmente, el artículo incluye las estrategias desarrolladas por Alpina para alcanzar los objetivos propuestos en estas políticas ambientales.

  14. Adaptation to altitude affects the senescence response to chilling in the perennial plant Arabis alpina

    Science.gov (United States)

    Wingler, Astrid; Juvany, Marta; Cuthbert, Caroline; Munné-Bosch, Sergi

    2015-01-01

    In annual plants with determinate growth, sugar accumulation signals high carbon availability once growth has ceased, resulting in senescence-dependent nutrient recycling to the seeds. However, this senescence-inducing effect of sugars is abolished at cold temperature, where sugar accumulation is important for protection. Here, natural variation was exploited to analyse the effect of chilling on interactions between leaf senescence, sugars, and phytohormones in Arabis alpina, a perennial plant with indeterminate growth. Eight accessions of A. alpina originating from between 2090 and 3090 m above sea level in the French Alps were used to identify heritable adaptations in senescence, stress response, sugars, and phytohormones to altitude. Accessions from high altitudes showed an enhanced capacity for sucrose accumulation and a diminished loss of chlorophyll in response to chilling. At warm temperature, sucrose content was negatively correlated with chlorophyll content, and sucrose treatment induced leaf senescence. Chilling resulted in lower indole-3-acetic acid, but higher zeatin and jasmonic acid contents. Interactions between sugar and phytohormones included a positive correlation between sucrose and jasmonic acid contents that may be involved in promoting the stress-dependent decline in chlorophyll. These findings reveal regulatory interactions that underlie adaptation in the senescence and stress response to chilling. PMID:25371506

  15. Transformation of Mortierella alpina (fatty acid supplier myceliums via AMT system (Agrobacterium Mediated Transformation

    Directory of Open Access Journals (Sweden)

    Aida Javanmard

    2016-09-01

    Full Text Available Introduction: Mortierella alpina is one of the most important fungi in food industry because of having ability of synthesizing unsaturated fatty acids, particularly Arashidonic Acid. This is a precursor of Eicosanoidregulate-lipoprotein metabolism which is involved in blood rheology, platelet activation and leukocyte-function, and the functional characteristics of the cell membrane. Materials and methods: In this study genetic transformation of M. alpina CBS754.68 fungus was evaluated via Agrobacterium tumefaciens and Agrobacterium rhizogenes. Agrobacteriums containing pBI121 vector were used for transformation of three days of old mycelia. Three days old hyphae were exposed to the bacteria with three level of time (one, two and three hours in the present of acetosyringone. Mitotic stability of the third generation of transgenic (T2 was confirmed by GUS assay and amplification of CaMV 35S promoter by polymerase chain reaction. Results: The highest percentage of transformation and mitotic stability were obtained by using A. tumefaciens and A. rhizogenese, respectively. Discussion and conclusion: The results showed that to obtain more efficient and more stable transformation, the fundamental factor is the use of suitable species of Agrobacterium. It is the first report for transformation of autothroph strain of M. alpine via Agrobacterium.

  16. Novel, male-produced aggregation pheromone of the cerambycid beetle Rosalia alpina, a priority species of European conservation concern.

    Directory of Open Access Journals (Sweden)

    Alenka Žunič Kosi

    Full Text Available Several recent studies have demonstrated the great potential for exploiting semiochemicals in ecology and conservation studies. The cerambycid beetle Rosalia alpina represents one of the flagship species of saproxylic insect biodiversity in Europe. In recent years its populations appear to have declined substantially, and its range has shrunk considerably as a result of forest management and urbanization. Here, we collected volatile chemicals released by males and females of R. alpina. Analyses of the resulting extracts revealed the presence of a single male-specific compound, identified as a novel alkylated pyrone structure. In field bioassays in Slovenia, traps baited with the synthesized pyrone captured both sexes of R. alpina, indicating that the pyrone functions as an aggregation pheromone. Our results represent the first example of a new structural class of pheromones within the Cerambycidae, and demonstrate that pheromone-baited traps can provide a useful tool for sampling R. alpina. This tool could be particularly useful in the ongoing development of conservation strategies for the iconic but endangered Alpine longicorn.

  17. 76 FR 69323 - Notice of Receipt of Petition for Decision that Nonconforming 1987-1994 ALPINA Burkard...

    Science.gov (United States)

    2011-11-08

    ... Systems, 105 Hydraulic Brake Systems, 106 Brake Hoses, 107 Reflecting Surfaces, 109 New Pneumatic Tires, 113 Hood Latch System, 116 Motor Vehicle Brake Fluids, 124 Accelerator Control Systems, 201 Occupant... Nonconforming 1987-1994 ALPINA Burkard Bovensiepen GmbH B11 Sedan Model Passenger Cars Are Eligible for...

  18. 78 FR 59092 - Notice of Receipt of Petition for Decision that Nonconforming 1988-1996 Alpina B10 Passenger Cars...

    Science.gov (United States)

    2013-09-25

    ... Windshield Wiping and Washing Systems, 105 Hydraulic and Electric Brake Systems, 106 Brake Hoses, 107 Reflective Surfaces, 109 New Pneumatic Tires, 113 Hood Latch System, 116 Motor Vehicle Brake Fluids, 124... Nonconforming 1988-1996 Alpina B10 Passenger Cars Are Eligible for Importation AGENCY: National Highway Traffic...

  19. 75 FR 51164 - Notice of Receipt of Petition for Decision That Nonconforming 1990-1996 ALPINA Burkard...

    Science.gov (United States)

    2010-08-18

    ... Hydraulic Brake Systems, 106 Brake Hoses, 107 Reflecting Surfaces, 109 New Pneumatic Tires, 113 Hood Latch System, 116 Motor Vehicle Brake Fluids, 124 Accelerator Control Systems, 201 Occupant Protection in... Nonconforming 1990-1996 ALPINA Burkard Bovensiepen GmbH B12 2-Door Coupe Model Passenger Cars Are Eligible for...

  20. Root microbiota dynamics of perennial Arabis alpina are dependent on soil residence time but independent of flowering time.

    Science.gov (United States)

    Dombrowski, Nina; Schlaeppi, Klaus; Agler, Matthew T; Hacquard, Stéphane; Kemen, Eric; Garrido-Oter, Ruben; Wunder, Jörg; Coupland, George; Schulze-Lefert, Paul

    2017-01-01

    Recent field and laboratory experiments with perennial Boechera stricta and annual Arabidopsis thaliana suggest that the root microbiota influences flowering time. Here we examined in long-term time-course experiments the bacterial root microbiota of the arctic-alpine perennial Arabis alpina in natural and controlled environments by 16S rRNA gene profiling. We identified soil type and residence time of plants in soil as major determinants explaining up to 15% of root microbiota variation, whereas environmental conditions and host genotype explain maximally 11% of variation. When grown in the same soil, the root microbiota composition of perennial A. alpina is largely similar to those of its annual relatives A. thaliana and Cardamine hirsuta. Non-flowering wild-type A. alpina and flowering pep1 mutant plants assemble an essentially indistinguishable root microbiota, thereby uncoupling flowering time from plant residence time-dependent microbiota changes. This reveals the robustness of the root microbiota against the onset and perpetual flowering of A. alpina. Together with previous studies, this implies a model in which parts of the root microbiota modulate flowering time, whereas, after microbiota acquisition during vegetative growth, the established root-associated bacterial assemblage is structurally robust to perturbations caused by flowering and drastic changes in plant stature.

  1. Disturbance and Stand Development of a Colorado Subalpine Forest

    OpenAIRE

    Veblen, Thomas T.; Hadley, Keith S; Reid, Marion S

    1991-01-01

    Stand development patterns were examined in an Engelmann spruce (Picea engelmannii), subalpine fir (Abies lasiocarpa) and lodgepole pine (Pinus contorta var. latifolia) forest in Rocky Mountain National Park in northern Colorado. Two old-growth stands (with fine-scale windthrows dominating dynamics) and a 260-yr-old post-fire stand were sampled for tree ages, sizes, growth, and replacement patterns in windthrow gaps. Visual assessment of frequency of growth releases in increment cores, and de...

  2. Glaciimonas alpina sp. nov. isolated from alpine glaciers and reclassification of Glaciimonas immobilis Cr9-12 as the type strain of Glaciimonas alpina sp. nov.

    Science.gov (United States)

    Frasson, David; Udovičić, Matije; Frey, Beat; Lapanje, Aleš; Zhang, De-Chao; Margesin, Rosa; Sievers, Martin

    2015-06-01

    Psychrophilic bacterial strains were isolated from alpine glaciers in Switzerland and characterized taxonomically. On the basis of phylogenetic analysis of partial 16S rRNA and rpoB genes, three of those strains, strain 79 ( = CCOS 247), strain 4/58 ( = CCOS 250) and strain 4/56 ( = CCOS 258) clustered together with strain Cr9-12T and separately from the type strains Glaciimonas immobilis Cr9-30T and Glaciimonas singularis LMG 27070T. Strain Cr9-12T has been previously described as a strain of G. immobilis. The three newly isolated strains were compared phenotypically with strain Cr9-12T and with the type strains of the species G. immobilis and G. singularis. Cr9-12T and the three novel strains from an alpine glacier in Switzerland were Gram-stain-negative, non-motile, rod-shaped and psychrophilic and showed good growth throughout a temperature range of 1-20 °C and characteristically oxidized d-mannitol, l-fucose and bromosuccinic acid. The predominant cellular fatty acids of strain Cr9-12T and the three novel strains were summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH), C16 : 0 and C18 : 1ω7c. The respiratory quinone of these strains was ubiquinone 8 (UQ-8). The genomic DNA G+C content of Cr9-12T was 49.2 mol%. The combined data from phenotypic, phylogenetic and DNA-DNA relatedness studies strongly support the reclassification of strain Cr9-12T as representing a novel species. This strain and the isolates 79 ( = CCOS 247), 4/58 ( = CCOS 250) and 4/56 ( = CCOS 258) are representatives of a novel species of the genus Glaciimonas, for which the name Glaciimonas alpina sp. nov. is proposed. The type strain of Glaciimonas alpina is Cr9-12T ( = CCOS 761T = DSM 22814T).

  3. Genetic structure along a gaseous organic pollution gradient: a case study with Poa annua L

    Energy Technology Data Exchange (ETDEWEB)

    Chen Xiaoyong; Li Ning; Shen Lang; Li Yuanyuan

    2003-08-01

    Genetic composition of Poa annua populations showed clinal change along an organic pollution gradient. - The population genetic composition of Poa annua L. was studied by starch electrophoresis along a transect running NE from an organic reagents factory at Shanghai, China. Five enzyme systems were stained. We have reached the following preliminary conclusions: (1) Organic pollution has dramatically changed genotypic frequencies at some loci of Poa annua populations. At polluted sites, significant deviations from Hardy-Weinberg equilibrium were observed on loci Sod-1 and Me due to the excess of heterozygote. Especially in the two nearest sites to pollution source, all the individuals were heterozygous at locus Sod-1. The data suggests that heterozygotes were more tolerant to organic pollution than homozygotes, indicating the fitness superiority of heterozygotes. (2) A tendency towards clinal changes of allele frequencies was found at some polymorphic loci. Frequencies of the common alleles at loci Sod-1, Me and Fe-1 increased as the distance to the pollution source increased. (3) The effective number of alleles per locus, and the observed and expected heterozygosity were much higher in the pollution series than in the clear control site (Botanic Park population), but genetic multiplicity (number of alleles per locus) was lower than for the control. (4) Most genetic variability was found within populations, and only 2.56% were among populations of the polluted series. However, 9.48% of the total genetic variation occurred among populations when including the Botanic Park population. The genetic identity between populations of the pollution series (0.9869-1.0000, mean 0.9941) was higher than those between the pollution series and the Botanic Park population. UPGMA divided the five populations into two groups. One contained the four polluted populations, and the other only contained the Botanic Park population.

  4. SDN-POA volume, sexual behavior, and partner preference of male rats affected by perinatal treatment with ATD.

    Science.gov (United States)

    Houtsmuller, E J; Brand, T; de Jonge, F H; Joosten, R N; van de Poll, N E; Slob, A K

    1994-09-01

    The present study investigated 1) the importance of the aromatization process during the perinatal period for the development of the sexually dimorphic nucleus in the preoptic area of the hypothalamus (SDN-POA) of male rats, and 2) the relationship between SDN-POA volume and parameters of masculinization in male rats that were treated perinatally with the aromatase-inhibitor ATD. Males were treated with ATD either prenatally or pre- and neonatally, or with the vehicle. Masculine sexual behavior and partner preference were investigated in adulthood. Thereafter, animals were sacrificed and SDN-POA volume was measured. The SDN-POA volume was reduced in both the prenatally and the pre- and neonatally treated group, with a larger reduction in the latter than in the former group. Combined pre- and neonatal ATD treatment resulted in reduced frequency of mounts, intromissions, and ejaculations, as well as a reduced preference for a female over a male. The SDN-POA size was significantly and positively correlated with frequency of masculine sexual behavior, as well as preference for a female over a male.

  5. Evaluation of storage and filtration protocols for alpine/subalpine lake water quality samples

    Science.gov (United States)

    John L. Korfmacher; Robert C. Musselman

    2007-01-01

    Many government agencies and other organizations sample natural alpine and subalpine surface waters using varying protocols for sample storage and filtration. Simplification of protocols would be beneficial if it could be shown that sample quality is unaffected. In this study, samples collected from low ionic strength waters in alpine and subalpine lake inlets...

  6. Ozone and modeled stomatal conductance at a high elevation subalpine site in southeastern Wyoming

    Science.gov (United States)

    Robert C. Musselman; Karl F. Zeller; Nedialko T. Nikolov

    1998-01-01

    Ozone concentrations have been monitored at the Glacier Lakes Ecosystem Experiment Site (GLEES) in the Snowy Range of the Medicine Bow Mountains 55 km west of Laramie, Wyoming, USA. The site is located at 3,186 m elevation in a large subalpine meadow of a mature subalpine forest near timberline. Continuous ozone and meteorological monitoring are a part of the GLEES...

  7. Production of Arachidonic Acid by Mortierella alpina I49-N18

    Directory of Open Access Journals (Sweden)

    Ji Wang

    2002-01-01

    Full Text Available Arachidonic acid (AA, an essential fatty acid in human body, fermented by Mortierella alpina I49-N18 was investigated in a shake-flask, and a 50-ton fermentor. In order to optimize the culture conditions, the effects of temperature, initial pH, culture time, carbon and nitrogen sources were studied. Furthermore, the way of adding sugar during fermentation was evaluated in a 50-ton fermentor. Under the optimum culture conditions, arachidonic acid produced in shake-flask and 50-ton fermentor was 4.55 and 5.11 g/L media, respectively. It was shown that the highest percentage of AA in lipids in shake-flask and 50-ton fermentor reached 70.20 and 53.01 %, respectively. Gas chromatography/mass spectrometry tests showed that the oil contained 80 % of polyunsaturated fatty acids such as arachidonic acid, γ-linolenic acid, and linoleic acid.

  8. Micropropagación in vitro de Nothofagus alpina utilizando fitohormonas

    Directory of Open Access Journals (Sweden)

    Luz García Cruzatty

    2015-09-01

    Full Text Available Nothofagus alpina es una de las especies forestales más importantes del Sur de Chile y Argentina, países donde se ha empezado con programas de mejoramiento genético. La micropropagación es una técnica muy útil en la clonación de árboles con fines de mejoramiento, por tanto, los objetivos planteados en esta investigación fueron: determinar la mejor concentración de fitohormonas 6-bencilaminopurina (BAP y ácido indol butírico (AIB y, el medio de cultivo idóneo para inducir el enraizamiento de brotes y la brotación de secciones nodales de N. alpina. Se evaluaron los medios de Murashige Skoog (MS y Wood Plant Medium (WPM, con la mitad de los macronutrientes (enraizamiento y los micronutrientes completos (multiplicación, suplementado con peptone (0.1%, sacarosa (2.0%, agar (0.7% y diferentes concentraciones de auxinas. El medio MS suplementado con 2 mg L-1 de AIB resultó mejor para inducir la producción de las raíces, tanto en número como en la longitud de la raíz principal. El mayor porcentaje de enraizamiento se registró en el medio WPM suplementado con 2 mg L-1 AIB. Los tratamientos para inducir multiplicación que incluyeron citoquinina originaron callos y no enraizaron; siendo mayor la presencia de callos en el medio WPM. Se sugiere que la aplicación de citoquininas no es indispensable para la brotación, puesto que en los tratamientos testigos hubo una buena brotación; lo que hace suponer que el material vegetal utilizado tiene suficiente niveles endógenos de esta fitohormona.

  9. Biochemical characterization of GDP-L-fucose de novo synthesis pathway in fungus Mortierella alpina

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Yan [TEDA School of Biological Sciences and Biotechnology, Nankai University, Tianjin Economic-Technological Development Area, Tianjin 300457 (China); Perepelov, Andrei V. [N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky Prospekt 47, 119991 Moscow (Russian Federation); Wang, Haiyan [TEDA School of Biological Sciences and Biotechnology, Nankai University, Tianjin Economic-Technological Development Area, Tianjin 300457 (China); Zhang, Hao [State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122 (China); Knirel, Yuriy A. [N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky Prospekt 47, 119991 Moscow (Russian Federation); Wang, Lei [TEDA School of Biological Sciences and Biotechnology, Nankai University, Tianjin Economic-Technological Development Area, Tianjin 300457 (China); Chen, Wei, E-mail: weichen@jiangnan.edu.cn [State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122 (China)

    2010-01-22

    Mortierella alpina is a filamentous fungus commonly found in soil, which is able to produce large amount of polyunsaturated fatty acids. L-Fucose is an important sugar found in a diverse range of organisms, playing a variety of biological roles. In this study, we characterized the de novo biosynthetic pathway of GDP-L-fucose (the nucleotide-activated form of L-fucose) in M. alpina. Genes encoding GDP-D-mannose 4,6-dehydratase (GMD) and GDP-keto-6-deoxymannose 3,5-epimerase/4-reductase (GMER) were expressed heterologously in Escherichia coli. The recombinant enzymes were produced as His-tagged fusion proteins. Conversion of GDP-mannose to GDP-4-keto-6-deoxy mannose by GMD and GDP-4-keto-6-deoxy mannose to GDP-L-fucose by GMER were analyzed by capillary electrophoresis, electro-spray ionization-mass spectrometry, and nuclear magnetic resonance spectroscopy. The k{sub m} values of GMD for GDP-mannose and GMER for GDP-4-keto-6-deoxy mannose were determined to be 0.77 mM and 1.047 mM, respectively. Both NADH and NADPH may be used by GMER as the coenzyme. The optimum temperature and pH were determined to be 37 {sup o}C and pH 9.0 (GMD) or pH 7.0 (GMER). Divalent cations are not required for GMD and GMER activity, and the activities of both enzymes may be enhanced by DTT. To our knowledge this is the first report on the characterization of GDP-L-fucose biosynthetic pathway in fungi.

  10. Masculinization of betta fish Betta splendens by embryo immersion in extract of purwoceng Pimpinella alpina

    Directory of Open Access Journals (Sweden)

    Harton Arfah

    2015-05-01

    Full Text Available ABSTRACT This study aimed to examine the effect of extract of purwoceng Pimpinella alpina for masculinization of Betta splendens. This research used completely randomized design with three treatments that were distinguished by doses of purwoceng extract, which were 10, 20, and 30 µL/L, and 0 µL/L as control. The treatments were given by immersion to 35 embryos at eye spots phase or about 28-hours after fertilization, for eight hours. The immersion process was done for 8 hours. The result showed that 20 µL/L dose of purwoceng extract produced 62.66% male, and hatching rate was 85.71%. This male percentage was higher compared to control (45.91%, but the hatching rate was lower than that of control (98.57%. At the higher dose (30 µL/L, male fish population and hatching rate reduced respectively 39.72% and 68.57%, respectively. Keywords: masculinization, embryo immersion, purwoceng extract, Betta splendens  ABSTRAK Penelitian ini bertujuan untuk mengevaluasi pengaruh dosis ekstrak purwoceng Pimpinella alpina extract dalam maskulinisasi ikan cupang hias Betta splendens. Penelitian ini menggunakan metode rancangan acak lengkap dengan tiga perlakuan dan tiga ulangan dosis ekstrak purwoceng. yaitu 10, 20, dan 30 µL/L, serta perlakuan 0 µL/L sebagai kontrol. Perlakuan diberikan melalui perendaman selama delapan jam terhadap 35 embrio saat memasuki fase bintik mata atau sekitar jam ke-28 setelah pembuahan. Hasil penelitian menunjukkan bahwa dosis ekstrak purwoceng 20 µL/L menghasilkan persentase ikan jantan sebesar 62,66%, dan daya tetas telur sebesar 85,71%. Persentase jantan tersebut lebih tinggi daripada kontrol (45,1%, tetapi derajat penetasannya lebih rendah daripada kontrol (98,57%. Pada dosis yang lebih tinggi (30 µL/L, populasi ikan jantan (39,72%, dan derajat penetasan (68,57% adalah menurun. Kata kunci: maskulinisasi, perendaman embrio, ekstrak purwoceng, Betta splendens

  11. Fire, fuel composition and resilience threshold in subalpine ecosystem.

    Directory of Open Access Journals (Sweden)

    Olivier Blarquez

    Full Text Available BACKGROUND: Forecasting the effects of global changes on high altitude ecosystems requires an understanding of the long-term relationships between biota and forcing factors to identify resilience thresholds. Fire is a crucial forcing factor: both fuel build-up from land-abandonment in European mountains, and more droughts linked to global warming are likely to increase fire risks. METHODS: To assess the vegetation response to fire on a millennium time-scale, we analyzed evidence of stand-to-local vegetation dynamics derived from sedimentary plant macroremains from two subalpine lakes. Paleobotanical reconstructions at high temporal resolution, together with a fire frequency reconstruction inferred from sedimentary charcoal, were analyzed by Superposed Epoch Analysis to model plant behavior before, during and after fire events. PRINCIPAL FINDINGS: We show that fuel build-up from arolla pine (Pinus cembra always precedes fires, which is immediately followed by a rapid increase of birch (Betula sp., then by ericaceous species after 25-75 years, and by herbs after 50-100 years. European larch (Larix decidua, which is the natural co-dominant species of subalpine forests with Pinus cembra, is not sensitive to fire, while the abundance of Pinus cembra is altered within a 150-year period after fires. A long-term trend in vegetation dynamics is apparent, wherein species that abound later in succession are the functional drivers, loading the environment with fuel for fires. This system can only be functional if fires are mainly driven by external factors (e.g. climate, with the mean interval between fires being longer than the minimum time required to reach the late successional stage, here 150 years. CONCLUSION: Current global warming conditions which increase drought occurrences, combined with the abandonment of land in European mountain areas, creates ideal ecological conditions for the ignition and the spread of fire. A fire return interval of less

  12. A new Epichloe species with interspecific hybrid origins from Poa pratensis ssp. pratensis in Liyang, China.

    Science.gov (United States)

    Yan, Kang; Yanling, Ji; Kunran, Zhu; Hui, Wang; Huimin, Miao; Zhiwei, Wang

    2011-01-01

    We describe a new Epichloë species found in symbiosis with Poa pratensis ssp. pratensis in Liyang, China. Stromata characteristic of Epichloë spp. were present on some of the reproductive tillers of individual host grasses. Only three of the 98 stromata observed on field plants became orange and produced perithecia. Phylogenetic analyses based on sequences of tubB and tefA indicated that this Epichloë sp. was an interspecific hybrid related to both E. yangzii and members in the E. typhina complex clade (ETC). Allele-1 of tefA and tubB grouped in the E. bromicola/E. yangzii clade; allele-2 of these two genes clustered in a distinct subclade in the ETC. This is the first report of an Epichloë species that has interspecific hybrid origins. We propose the name Epichloë liyangensis Z. Wang, Y. Kang et H. Miao, sp. nov. for this species.

  13. Identification of apomixis in the Kentucky bluegrass (Poa pratensis L. using auxin test

    Directory of Open Access Journals (Sweden)

    Janetta Niemann

    2012-08-01

    Full Text Available The effect of auxin treatment on the formation of apomictic – endospermless grains in Poa pratensis was investigated in the study. Four Polish cultivars: Skiz, Eska 46, Alicja, Ani as well as six breeding lines: POB 13, SK-W-33, SKW-15, SKW-35A, SK-W-35A and SK-W-35B were tested by embryological methods to reveal the reproduction pathway in greenhouse and field conditions. The obtained results showed that four genotypes, i.e. Alicja, Ani, Eska 46 and SK-W-35B are facultative apomictic and the other have formed seeds only on the apomictic way. In facultative apomicts it was found that in many cases both endospermless ovules containing embryo sacs with embryos or embryo sacs with well developed endosperm were formed. In the case of apomictic genotypes only endospermless seeds were observed.

  14. Groundwater transport of crater-lake brine at Poa´s Volcano, Costa Rica

    Science.gov (United States)

    Sanford, Ward E.; Konikow, Leonard F.; Rowe, Gary L.; Brantley, Susan L.

    1995-01-01

    Poa´s Volcano is an active stratovolcano in Costa Rica that has a lake in its active crater. The crater lake has high temperatures (50–90 °C), high acidity (pH ≈ 0.0), and a high dissolved-solids content (100 g/kg). The volcano has numerous freshwater springs on its flanks, but a few on the northwestern flank are highly acidic (pH = 1.6–2.5) and have high dissolved-solids concentrations (2–22 g/kg). This study analyzes the regional groundwater system at Poa´s and demonstrates the likelihood that the water discharging from the acidic springs in the Rio Agrio watershed originates at the acidic crater lake. Both heat and solute transport are analyzed on a regional scale through numerical simulations using the HST3D finite-difference model, which solves the coupled equations for fluid flow, heat transport, and solute transport. The code allows fluid viscosity and density to be functions of both temperature and solute concentration. The simulations use estimates for recharge to the mountain and a range of values and various distributions of permeability and porosity. Several sensitivity analyses are performed to test how the uncertainty in many of the model parameters affects the simulation results. These uncertainties yield an estimated range of travel times from the crater lake to the Rio Agrio springs of 1–30 years, which is in close agreement with the results of tritium analyses of the springs. Calculated groundwater fluxes into and out of the crater lake are both about several hundred kg/s. These fluxes must be accounted for in water budgets of the crater lake.

  15. Revision of Poa L. (Poaceae, Pooideae, Poeae, Poinae in Mexico: new records, re-evaluation of P. ruprechtii, and two new species, P. palmeri and P. wendtii

    Directory of Open Access Journals (Sweden)

    Robert Soreng

    2012-08-01

    Full Text Available A revision and key to the 23 species and eight subspecies of Poa (including Dissanthelium known to occur in Mexico is provided. All voucher specimens seen are cited for accepted taxa, except P. annua for which one voucher per state is provided. Taxa not previously known from, or poorly understood in, Mexico are discussed. Poa palmeri sp. nov. is endemic to forested slopes of the Sierra Madre Oriental, and we distinguished it from P. ruprechtii s.s., a species of central Mexico that is here emended to include P. sharpii (syn. nov.. Poa wendtii sp. nov. is described from the Sierra Santa Rosa in northern Coahuila. Poa tacanae is placed in synonymy in P. seleri. Poa gymnantha and P. occidentalis are newly reported for Mexico, and material historically identified as P. villaroelii are placed in P. chamaeclinos. The genus Dissanthelium is considered to belong within Poa, and the Mexican taxa, D. calycina subsp. mathewsii and D. californicum, are treated as P. calycina var. mathewsii and P. thomasii, respectively. Poa subsect. Papillopoa subsect. nov. is erected for P. mulleri. Lectotypes are designated for P. conglomerata and P. seleri.

  16. Comparative phytosocioogical investigation of subalpine alder thickets in southwestern Alaska and the North Pacific

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — We present the first vegetation analysis of subalpine alder (Alnus viridis) thickets in southwestern Alaska. The data are primarily from mesic, hilly and mountainous...

  17. Intercontinental genetic structure and gene flow in Dunlin (Calidris alpina), a potential vector of avian influenza

    Science.gov (United States)

    Miller, Mark P.; Haig, Susan M.; Mullins, Thomas D.; Ruan, Luzhang; Casler, Bruce; Dondua, Alexei; Gates, River H.; Johnson, J. Matthew; Kendall, Steven J.; Tomkovich, Pavel S.; Tracy, Diane; Valchuk, Olga P.; Lanctot, Richard B.

    2015-01-01

    Waterfowl (Anseriformes) and shorebirds (Charadriiformes) are the most common wild vectors of influenza A viruses. Due to their migratory behavior, some may transmit disease over long distances. Migratory connectivity studies can link breeding and nonbreeding grounds while illustrating potential interactions among populations that may spread diseases. We investigated Dunlin (Calidris alpina), a shorebird with a subspecies (C. a. arcticola) that migrates from nonbreeding areas endemic to avian influenza in eastern Asia to breeding grounds in northern Alaska. Using microsatellites and mitochondrial DNA, we illustrate genetic structure among six subspecies: C. a. arcticola, C. a. pacifica, C. a. hudsonia, C. a. sakhalina, C. a. kistchinski, and C. a. actites. We demonstrate that mitochondrial DNA can help distinguish C. a. arcticola on the Asian nonbreeding grounds with >70% accuracy depending on their relative abundance, indicating that genetics can help determine whether C. a. arcticola occurs where they may be exposed to highly pathogenic avian influenza (HPAI) during outbreaks. Our data reveal asymmetric intercontinental gene flow, with some C. a. arcticola short-stopping migration to breed with C. a. pacifica in western Alaska. Because C. a. pacifica migrates along the Pacific Coast of North America, interactions between these subspecies and other taxa provide route for transmission of HPAI into other parts of North America.

  18. Improving arachidonic acid fermentation by Mortierella alpina through multistage temperature and aeration rate control in bioreactor.

    Science.gov (United States)

    Gao, Min-Jie; Wang, Cheng; Zheng, Zhi-Yong; Zhu, Li; Zhan, Xiao-Bei; Lin, Chi-Chung

    2016-05-18

    Effective production of arachidonic acid (ARA) using Mortierella alpina was conducted in a 30-L airlift bioreactor. Varying the aeration rate and temperature significantly influenced cell morphology, cell growth, and ARA production, while the optimal aeration rate and temperature for cell growth and product formation were quite different. As a result, a two-stage aeration rate control strategy was constructed based on monitoring of cell morphology and ARA production under various aeration rate control levels (0.6-1.8 vvm). Using this strategy, ARA yield reached 4.7 g/L, an increase of 38.2% compared with the control (constant aeration rate control at 1.0 vvm). Dynamic temperature-control strategy was implemented based on the fermentation performance at various temperatures (13-28°C), with ARA level in total cellular lipid increased by 37.1% comparing to a constant-temperature control (25°C). On that basis, the combinatorial fermentation strategy of two-stage aeration rate control and dynamic temperature control was applied and ARA production achieved the highest level of 5.8 g/L.

  19. Screening of Potential Free Radicals Scavenger and Antibacterial Activities of Purwoceng (Pimpinella alpina Molk).

    Science.gov (United States)

    Wahyuningrum, Retno; Utami, Pri Iswati; Dhiani, Binar Asrining; Kumalasari, Malikhah; Kusumawardani, Rizka Sari

    2016-11-01

    Purwoceng (Pimpinella alpina Molk) is a traditional medicinal plant used for its aphrodisiac values. This plant was originated Dieng Plateu, Central Java, Indonesia. Purwoceng has been reported to contain steroid, flavonoids, glycoside, saponins, tannins, and phenolic. Based on secondary metabolite compounds of Purwoceng herbs, a research need to be done to determine the other potential free radicals scavenger and antibacterial activities of Purwoceng. The objectives of this research are to screen the potential free radicals scavenger activity of in vitro using DPPH (1,1 diphenyl-2-picryl-hydrazil) radicals and NO• (nitric oxide) radicals, and antibacterial activity of Purwoceng. The extraction is done by a maceration method with petroleum ether, ethyl acetate, and ethanol solvent, respectively. Free radicals scavenger test was performed using DPPH radicals and NO• radicals, while antibacterial activity screening was performed using agar diffusion test. The results showed that ethyl acetate extract of Purwoceng has free radical scavenger activity with IC50 53.07 ppm lower than butylated hydroxytoluene. Ethyl acetate extract and ethanol extract of Purwoceng have antibacterial activity against Staphyloccus aureus, Escherichia coli, and MG42 bacterial isolate.

  20. Groundwater transport of crater-lake brine at Poas Volcano, Costa Rica

    Science.gov (United States)

    Sanford, W.E.; Konikow, L.F.; Rowe, G.L.; Brantley, S.L.

    1995-01-01

    This study analyzes the regional groundwater system at Poas and demonstrates the likelihood that the water discharging from the acidic springs in the Rio Agrio watershed originates at the acidic crater lake. Both heat and solute transport are analyzed on a regional scale through numerical simulations using the HST3D finite-difference model, which solves the coupled equations for fluid flow, heat transport, and solute transport. The code allows fluid viscosity and density to be functions of both temperature and solute concentration. The simulations use estimates for recharge to the mountain and a range of values and various distributions of permeability and porosity. Several sensitivity analyses are performed to test how the uncertainty in many of the model parameters affects the simulation results. These uncertainties yield an estimated range of travel times from the crater lake to the Rio Agrio springs of 1-30 yr, which is in close agreement with the results of tritium analyses of the springs. Calculated groundwater fluxes into and out of the crater lake are both about several hundred kg/s. These fluxes must be accounted for in water budgets of the crater lake. -from Authors

  1. Assessing the importance of human activities for the establishment of the invasive Poa annua in Antarctica

    Directory of Open Access Journals (Sweden)

    Marco A. Molina-Montenegro

    2014-06-01

    Full Text Available Because of its harsh environmental conditions and remoteness, Antarctica is often considered to be at low risk of plant invasion. However, an increasing number of reports have shown the presence and spread of non-native plants in Antarctica; it is therefore important to study which factors control the invasion process in this ecosystem. Here, we assessed the role of different human activities on the presence and abundance of the invasive Poa annua. In addition, we performed a reciprocal transplant experiment in the field, and a manipulative experiment of germination with P. annua and the natives Colobanthus quitensis and Deschampsia antarctica, in order to unravel the effects of physical soil disturbance on the establishment and survival of P. annua. We found a positive correlation between abundance of P. annua and level of soil disturbance, and that survival of P. annua was 33% higher in sites with disturbed soil than non-disturbed. Finally, we found that disturbance conditions increased germination for P. annua, whereas for native species germination in experimentally disturbed soil was either unchanged or reduced compared to undisturbed soil. Our results indicate that human activities that modify abiotic soil characteristics could play an important role in the abundance of this invasive species. If the current patterns of human activities are maintained in Antarctica, the establishment success and spread of P. annua could increase, negatively affecting native flora.

  2. Cold Tolerance and Antioxidant Response of Poa Pratensis and Paspalum vaginatum

    Directory of Open Access Journals (Sweden)

    SH. Bizhani

    2015-12-01

    Full Text Available A limiting factor for prodution of turf grasses in temperate regions is their low level of cold tolerance. In order to elucidate the cold tolerance, physiological and biochemical responses of two turf species, this study was conducted at a controlled environment greenhouse of Faculty of Agriculture in Shiraz University, Shiraz, Iran by a factorial experiment in completely randomized design with three replicates. Factors consisted of two turf species including Kentucky bluegrass (Poa pratensis and seashore paspalum (Paspalum vaginatum and four temperatures: 25, 15, 5 and -5 °C. Data analysis revealed that decreased temperature resulted in significant increases in proline, soluble sugars contents and activity of peroxidase, ascorbate peroxidase, catalase and superoxide dismutase enzymes, although seashore paspalum indicated a significant drop in antioxidant enzymes activity at cold stress of -5 °C. Furthermore, decreased temperature brought about a significant decline in visual quality, chlorophyll, starch and relative water content. Seashore paspalum exhibited a greater deterioration in visual quality, chlorophyll and relative water content at -5 °C compared to Kentucky bluegrass. The results showed that Kentucky bluegrass withstood cold stress with a better and more efficient defensive mechanism in comparison with seashore paspalum, thus it is considered more tolerant to cold stress and could, potentially, be used in temperate regions.

  3. Genetic diversity of Poa pratensis L. depending on geographical origin and compared with genetic markers

    Directory of Open Access Journals (Sweden)

    Magdalena Szenejko

    2016-09-01

    Full Text Available Background Poa pratensis is one of the most common species of meadow grass in Europe. Most cultivars of the species found in Poland were originally derived from its ecotypes. We compared the effectiveness of the RAPD and ISSR methods in assessing the genetic diversity of the selected populations of P. pratensis. We examined whether these methods could be useful for detecting a possible link between the geographical origin of a given population and its assessed genetic variation. Methods The molecular markers RAPD and ISSR were used and their efficiency compared using, inter alia, statistical multivariate methods (UPGMA and PCA. Results The low value of Dice’s coefficient (0.369 along with the significantly high percentage of polymorphic products indicates a substantial degree of genetic diversity among the studied populations. Our results found a correlation between the geographical origin of the studied populations and their genetic variations. For ISSR, which proved to be the more effective method in that respect, we selected primers with the greatest differentiating powers correlating to geographical origin. Discussion The populations evaluated in this study were characterized by a high genetic diversity. This seems to confirm the hypothesis that ecotypes of P. pratensis originating from different regions of Central Europe with different terrain structures and habitat conditions can be a source of great genetic variability.

  4. Growth and reproduction of the alpine grasshopper Miramella alpina feeding on CO2-enriched dwarf shrubs at treeline.

    Science.gov (United States)

    Asshoff, Roman; Hättenschwiler, Stephan

    2005-01-01

    The consequences for plant-insect interactions of atmospheric changes in alpine ecosystems are not well understood. Here, we tested the effects of elevated CO(2) on leaf quality in two dwarf shrub species (Vaccinium myrtillus and V. uliginosum) and the response of the alpine grasshopper (Miramella alpina) feeding on these plants in a field experiment at the alpine treeline (2,180 m a.s.l.) in Davos, Switzerland. Relative growth rates (RGR) of M. alpina nymphs were lower when they were feeding on V. myrtillus compared to V. uliginosum, and were affected by elevated CO(2) depending on plant species and nymph developmental stage. Changes in RGR correlated with CO(2)-induced changes in leaf water, nitrogen, and starch concentrations. Elevated CO(2) resulted in reduced female adult weight irrespective of plant species, and prolonged development time on V. uliginosum only, but there were no significant differences in nymphal mortality. Newly molted adults of M. alpina produced lighter eggs and less secretion (serving as egg protection) under elevated CO(2). When grasshoppers had a choice among four different plant species grown either under ambient or elevated CO(2), V. myrtillus and V. uliginosum consumption increased under elevated CO(2) in females while it decreased in males compared to ambient CO(2)-grown leaves. Our findings suggest that rising atmospheric CO(2) distinctly affects leaf chemistry in two important dwarf shrub species at the alpine treeline, leading to changes in feeding behavior, growth, and reproduction of the most important insect herbivore in this system. Changes in plant-grasshopper interactions might have significant long-term impacts on herbivore pressure, community dynamics and ecosystem stability in the alpine treeline ecotone.

  5. Population dynamics of the species Plantago major L. and Poa annua L. in a replacement series experiment

    Directory of Open Access Journals (Sweden)

    Mijović A.

    2009-01-01

    Full Text Available Population dynamics of the species Plantago major L. and Poa annua L., typical representatives of ruderal vegetation, was analyzed in a replacement series experiment. The analyzed species were sown in an area with meadow vegetation, where the vegetation present had been previously removed by a total herbicide and additionally by hoeing. The objective of the experiment was to monitor growth dynamics and the effect of intra- and inter-specific interaction of the species Plantago major and Poa annua in conditions of different sowing densities and proportions. The effects of intra- and inter-specific interference and the density-dependent responses were assessed on the basis of several parameters (natality, mortality, age structure, and measures of ontogenetic changes. Based on the study results, it can be concluded that the responses of the species in the experiment were different, which is explained by different adaptive mechanisms, i.e., strategies, in the specific environmental conditions. An effect of the density dependent response was present in both species in the replacement series experiment. The response was amplified by water deficit caused by intensive evapora­tion of the bare soil. No effect of inter-specific interference was observed at the given densities of the study species on the sample plots. An effect of intra-specific interference of the species Plantago major and Poa annua was observed in the guise of a density-negative response of the rate of ontogenetic changes and fecundity.

  6. Size and quality of wood used by Rosalia alpina (Linnaeus, 1758) (Coleoptera: Cerambycidae) in beech woodlands of Gipuzkoa (northern Spain)

    OpenAIRE

    Castro, A.

    2012-01-01

    La conservación de la especie saproxilófaga legalmente protegida Rosalia alpina (Linnaeus, 1758) en los hayedos de Europa conlleva una gestión adecuada de los árboles muertos y moribundos. Sin embargo, los parámetros de los árboles preferidos (tamaño y calidad de la madera) permanecen aún poco conocidos. En esta contribución se analizan los datos de distribución procedentes de seis años de trabajo en cuatro Lugares de Interés Comunitario de la provincia de Gipuzkoa (norte de España). Los indi...

  7. Rol y habilidades del CIO. Tres casos de estudio en Colombia: Alpina, Banco de Bogotá, Grupo Aval

    OpenAIRE

    Moreno Pérez, Héctor Fernando

    2016-01-01

    Con base en la revisión de la literatura realizada acerca de los roles directivos y del rol de uno en particular que es el CIO, y tomando como referencia la información suministrada por los directivos de tecnologías de Información de las organizaciones Alpina, Banco de Bogotá y Grupo AVAL, el trabajo de investigación hace una descripción del contenido del rol de CIO e identifica las habilidades requeridas para el ejercicio de este rol en dichas organizaciones. Se espera que los resultados del...

  8. VARIABILIDAD MORFOLÓGICA DE LAS ESPECIES DEL COMPLEJO POA RESINULOSA (POACEAE Y SU RELACIÓN CON LAS ESPECIES DE LA SECCIÓN DIOICOPOA

    Directory of Open Access Journals (Sweden)

    M. Gabriela Fernández Pepi

    2008-01-01

    Full Text Available El complejo Poa resinulosa incluye un grupo de especies conformado por P. calchaquiensis, P. pedersenii y P. resinulosa, de difícil delimitación debido a que las entidades son afines en cuanto a su morfología, aunque presentan distribución disyunta. Para evaluar y analizar a las especies del complejo Poa resinulosa y especies afines al mismo complejo, se midieron 40 caracteres morfológicos y anatómicos en ejemplares de Poa calchaquiensis, P. lanigera, P. pilcomayensis y P. resinulosa. Esos datos se incorporaron a la matriz del conjunto de especies de Poa sección Dioicopoa confeccionada por Giussani (2000, incluyendo también a P. nubensis una nueva especie afín a P. calchaquiensis. Mediante el análisis de componentes principales y pruebas estadísticas, se circunscribió a las especies del complejo Poa resinulosa. Se describió a P. resinulosa como una variedad de P. ligularis, de la que se diferencia por poseer lígula corta, hojas y cañas de menor longitud, menor ancho de la lámina y estomas de menor tamaño. Se presenta una clave para la identificación de Poa ligularis var. resinulosa y taxones afines, y un mapa con la distribución geográfica de ambas variedades de P. ligularis.

  9. Influence of Supplementation of Vegetable Oil Blends on Omega-3 Fatty Acid Production in Mortierella alpina CFR-GV15

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    Ganesan Vadivelan

    2017-01-01

    Full Text Available Objectives of this study were designed for improved production of mycelial omega-3 fatty acids with particular reference to EPA and DHA from the oleaginous fungus Mortierella alpina CFR-GV15 under submerged low temperatures fermentation supplemented with linseed oil and garden cress oil as an additional energy source. The fungus was grown at 20°C temperature for four days initially followed by 12°C temperature for next five days. The basal medium contained starch, yeast extract, and a blend of linseed oil (LSO and garden cress oil (GCO in the ratio 1 : 1. Results of the study revealed that, after nine days of total incubation period, the enhancement of biomass was up to 16.7 g/L dry weight with a total lipid content of 55.4% (v/w. Enrichment of omega-3 fatty acids indicated a significant increase in fatty acid bioconversion (ALA 32.2±0.42%, EPA 7.9±0.1%, and DHA 4.09±0.2% by 2.5-fold. The two-stage temperature cultivation alters the fatty acid profile due to activation of the desaturase enzyme in the cellular levels due to which arachidonic acid (AA content reduced significantly. It can be concluded that Mortierella alpina CFR-GV15 is a fungal culture suitable for commercial production of PUFAs with enriched EPA and DHA.

  10. Climate, geography, and tree establishment in subalpine meadows of the Olympic Mountains, Washington, USA

    Science.gov (United States)

    Woodward, Andrea; Schreiner, Edward G.; Silsbee, D.G.

    1995-01-01

    Noticeable changes in vegetation distribution have occurred in the Pacific Northwest during the last century as trees have established in some subalpine meadows. To study the relationship of this process to climate, recently established trees were aged in six subalpine meadows in the Olympic Mountains, Washington. The sites represent three points along a steep precipitation gradient. Subalpine fir (Abies lasiocarpa) has been establishing at the dry end of the gradient, mountain hemlock (Tsuga mertensiana) at the wet end, and both species in the center. Establishment patterns were compared with deviations from the century-long average for these weather variables: winter precipitation, Palmer Drought Severity Index, and winter, October, and May temperatures. Results show that establishment occurred in dry areas when weather conditions were wetter than average, and in wet areas under drier than average conditions. Establishment at central sites did not show consistent relationships with climate. If future climatic conditions continue to warm, establishment of subalpine fir in subalpine meadows in dry areas may cease and mountain hemlock may resume in wet areas.

  11. Evaluation of a subchronic (13-week) oral toxicity study, preceded by an in utero exposure phase, with arachidonic acid oil derived from Mortierella alpina in rats

    NARCIS (Netherlands)

    Hempenius, R.A.; Lina, B.A.R.; Haggitt, R.C.

    2000-01-01

    Arachidonic acid oil (ARA-oil) derived from the fungus Mortierella alpina for use in infant nutrition was tested in a subchronic (13-week) oral toxicity study in rats, preceded by an in utero exposure phase. The ARA-oil was administered as admixture to the rodent diet at dose levels of 3000 ppm,

  12. Intertidal biofilm distribution underpins differential tide-following behavior of two sandpiper species (Calidris mauri and Calidris alpina) during northward migration

    NARCIS (Netherlands)

    Jimenez, A.; Elner, R.W.; Favaro, C.; Rickards, K.; Ydenberg, R.C.

    2015-01-01

    The discovery that some shorebird species graze heavily on biofilm adds importance to elucidating coastal processes controlling biofilm, as well as impetus to better understand patterns of shorebird use of intertidal flats. Western sandpipers (Calidris mauri) and dunlin (Calidris alpina) stopover in

  13. Current distribution of the Rosalia longicorn Rosalia alpina (LINNAEUS, 1758 (Coleoptera: Cerambycidae in Poland

    Directory of Open Access Journals (Sweden)

    Michalcewicz Jakub

    2015-03-01

    Full Text Available The former range of the Rosalia longicorn Rosalia alpina in Poland probably overlapped with the range of the European beech Fagus sylvatica. In the 20th century, the species was recorded in the following parts of Poland: the Carpathians (almost the entire range, the Świętokrzyskie Mountains, the Roztocze Upland, Lower Silesia, and the northern and northwestern parts of the country. Although the Rosalia longicorn appears to have regressed in the countries of central Europe, the current population trend of this species in Poland is not known. This study presents data on the distribution of the Rosalia longicorn in Poland in 2000-2013 and defines its current distribution and range. A total of 210 sites of the Rosalia longicorn were identified, situated in 42 UTM squares (10x10 km. The total area of the species’ occurrence (maximum convex polygon was 3334 km2 and the effectively used area was 1877 km2. The Rosalia longicorn has withdrawn from most of its former sites in Poland and at present occurs only in parts of the Carpathians. Its continuous distribution range comprises the Bieszczady Zachodnie and Beskid Niski Mountains. Scattered and less abundant sites occur in the Beskid Sądecki, Pieniny Mountains and Sanok-Turka Mountains. At present, therefore, the species’ range of occurrence in Poland is significantly smaller than that recorded in the 20th century. The median nearest neighbour distance between sites was 1023 m (mean = 1640 m ±1702 SD, range 502-10870 m. Those situated on the peripheries of the range are thinly scattered, and the distance between them is probably too large to allow free movement of the species. This can disrupt the current range and lead to the formation of isolated sites (islands along its peripheries, from which the Rosalia longicorn may gradually disappear. Such a development could cause its total extinction. The current distribution of the Rosalia longicorn in the Carpathians suggests that certain detrimental

  14. Gene regulation by NMDA receptor activation in the SDN-POA neurons of male rats during sexual development.

    Science.gov (United States)

    Hsu, Hseng-Kuang; Shao, Pei-Lin; Tsai, Ke-Li; Shih, Huei-Chuan; Lee, Tzu-Ying; Hsu, Chin

    2005-04-01

    The present study was designed to identify possible signaling pathways, which may play a role in prevention of neuronal apoptosis in the sexually dimorphic nucleus of the preoptic area (SDN-POA) after physiological activation of the N-methyl-D-aspartate (NMDA) receptor. Gene response to the blockage of the NMDA receptor by an antagonist (dizocilpine hydrogen maleate; MK-801) was screened after suppression subtractive hybridization (SSH). The results showed that differential screening after SSH detected the presence of some neurotrophic genes (RNA binding motif protein 3 (RBM3), alpha-tubulin) as well as apoptosis-related genes (Bcl-2, cytochrome oxidase subunit II, cytochrome oxidase subunit III) in the SDN-POA of male rats, which were down-regulated by blocking the NMDA receptor. The RT-PCR products of the aforementioned genes in MK-801-treated males were significantly less than that in untreated males. In particular, the expression of Bcl-2 mRNA, including Bcl-2 protein, in male rats were significantly suppressed by MK-801 treatment. Moreover, the binding activity of nuclear factor kappaB (NFkappaB) was significantly higher in male rats than in females, but significantly diminished by blocking the NMDA receptor with MK-801 in male rats. No significant difference in cAMP response element-binding protein (CREB) binding activity was observed among untreated male, MK-801-treated male, untreated female and MK-801-treated female groups. These results suggest that genes regulated by NMDA receptor activation might participate in neuronal growth and/or anti-apoptosis, and support an important signaling pathway of NFkappaB activation and its target gene, Bcl-2, in preventing neuronal apoptosis in the SDN-POA of male rats during sexual development.

  15. Turismo, información, cambio climático: el caso del Parque Nacional Volcan Poas, Costa Rica

    OpenAIRE

    Juan Antonio Aguirre González

    2011-01-01

    El cambio climático es el tema ambiental más importante de este siglo. El estudio se condujo entre 2008/2009 y el trabajo de campo durante los meses de abril y mayo del 2008, cuando un total de 996 visitantes fueron entrevistados en el Parque Nacional, Volcán Poas Costa Rica, en relación a sus actitudes hacia el cambio del clima y sobre, cómo y donde ellos consiguen su información en el tema. Los visitantes del parque que se entrevistaron promedian entre 30 a 50 años de edad, (CR 31,USA 40 EU...

  16. Phenology of plants in relation to ambient environment in a subalpine forest of Uttarakhand, western Himalaya.

    Science.gov (United States)

    Bisht, Vinod K; Kuniyal, Chandra P; Bhandari, Arvind K; Nautiyal, Bhagwati P; Prasad, P

    2014-07-01

    Observations on phenology of some representative trees, shrubs, under-shrubs and herbs in a subalpine forest of Uttarakhand, western Himalaya were recorded. With the commencement of favorable growth season in April, occurrence of leaf fall was indicatory growth phenomenon in Quercus semecarpifolia, Q. floribunda and Abies spectabilis. However, active vegetative growth in herbaceous species starts onward April and fruit maturation and seed dehiscence are completed from mid of September to October. In general, vegetative growth and reproductive stages in majority of the studied species seems to be dependent on adequate moisture content and also flowering and fruiting in subalpine plants correlate ambient temperature.

  17. Effects of prenatal stress on differentiation of the sexually dimorphic nucleus of the preoptic area (SDN-POA) of the rat brain.

    Science.gov (United States)

    Anderson, D K; Rhees, R W; Fleming, D E

    1985-04-15

    The present study was designed to determine the effects of prenatal malnutrition or environmental stress on the development of the sexually dimorphic nucleus of the preoptic area (SDN-POA). Pregnant rats were divided into a control group and two treatment groups (immobilization-illumination-heat or environmental stress, and nutritional stress). The two forms of stress were administered during the third trimester of gestation (days 14-20). Male and female offspring were sacrificed at birth, 20, and 60 days postnatally. The cross-sectional area of the SDN-POA was identified under light microscopy and was measured. The data confirm previous studies by showing a significant sex difference in the SDN-POA between control male and female rats. Prenatally stressed males sacrificed 20 and 60 days after birth showed SDN-POA areas 50% smaller than the nuclear areas of control males. The size of the SDN-POA of female offspring, however, was not significantly altered by prenatal treatments.

  18. Permanent effects of postnatal administration of beta-adrenergic ligands on the volume of sexually dimorphic nucleus of the preoptic area (SDN-POA) in rats.

    Science.gov (United States)

    Izdebska-Straszak, Grazyna; Gubala, Elzbieta; Jedrzejowska-Szypulka, Halina; Klencki, Mariusz; Wiczkowski, Andrzej; Jarzab, Barbara

    2006-01-01

    beta-adrenergic ligands have been shown to influence sexual differentiation of the brain. In the present study we document that short postnatal treatment with beta-adrenergic agonists or antagonists may permanently reverse the morphological sex of the brain, as judged by the volume of sexually dimorphic nucleus of the preoptic area (SDN-POA). Female rats treated by beta(2)-adrenergic stimulating ligands exhibit an increased, male type SDN-POA volume while male rats treated by beta1-adrenergic antagonists show a decreased, female type of SDN-POA volume. To analyze the volume of SDN-POA of adult rats after postnatal administration of betaadrenergic ligands. From the second day of life, over 5 consecutive days, all the neonates were injected subcutaneously with the following drugs: isoproterenol, salbutamol, metoprolol alprenolol or saline. SDN-POA volumes were estimated planimetrically on serial brain slides. In male rats the mean volume of SDN-POA was 9.97 +/- 1.66 x 10(-3) mm(3), in female rats the respective volume reached 4.02 +/- 1.26 x 10(-3) mm(3) only and was 2.5 times lower, the difference being highly statistically significant. Postnatal administration of isoproterenol remained without effect in male rats but diminished the SDN-POA volume in female rats, thus increasing the sexual dimorphism. The disappearance of sexual dimorphism was noted in rats treated postnatally with salbutamol. This effect was due to the increase in SDN-POA volumes in female rats, up to 9.81 +/- 2.64 x 10(-3) mm(3), the levels approaching the male type of POA differentiation. Postnatal alprenolol treatment influenced the sexual dimorphism of the brain by decreasing the SDN-POA volume reached by adult males. In fact, in rats treated postnatally with alprenolol, the volume of the nucleus reached only 4,44 +/- 1,61 x 10(-3) mm(3), being not statistically different from female nuclei. The effect of metoprolol pretreatment was similar to alprenolol. Male volumes of SDN-POA were restored

  19. Size and quality of wood used by Rosalia alpina (Linnaeus, 1758 (Coleoptera: Cerambycidae in beech woodlands of Gipuzkoa (northern Spain

    Directory of Open Access Journals (Sweden)

    CASTRO, A., MARTINEZ DE MURGUIA, L., FERNANDEZ, J., CASIS, A., MOLINO-OLMEDO, F.

    2012-01-01

    Full Text Available La conservación de la especie saproxilófaga legalmente protegida Rosalia alpina (Linnaeus, 1758 en los hayedos de Europa conlleva una gestión adecuada de los árboles muertos y moribundos. Sin embargo, los parámetros de los árboles preferidos (tamaño y calidad de la madera permanecen aún poco conocidos. En esta contribución se analizan los datos de distribución procedentes de seis años de trabajo en cuatro Lugares de Interés Comunitario de la provincia de Gipuzkoa (norte de España. Los individuos vivos de R. alpina y sus orificios de emergencia fueron registrados exclusivamente en hayas. 72 individuos vivos y 520 orificios fueron registrados en 77 árboles. Las evidencias de ocupación (presencia de individuos vivos o de orificios o de ambos fueron más frecuentes en troncos Ø > 25 cm de hayas en pie (tanto aún vivas como muertas que en ramas y árboles caídos y más delgados. Sin embargo, el número de orificios no mostró diferencias entre las clases de tamaño y la calidad de la madera de los troncos principales. Las ramas más gruesas (Ø > 15 cm registraron mayores tasas de presencia y número de orificios que las más finas. Conociendo los tipos de árboles más seleccionados, se sugiere la elaboración de un mapa regional de disponibilidad de hábitat como herramienta práctica para planificar estrategias de conservación.

  20. Linkages between grazing history and herbivore exclusion on decomposition rates in mineral soils of subalpine grasslands

    Science.gov (United States)

    Alan G. Haynes; Martin Schutz; Nina Buchmann; Deborah S. Page-Dumroese; Matt D. Busse; Anita C. Risch

    2014-01-01

    Herbivore-driven changes to soil properties can influence the decomposition rate of organic material and therefore soil carbon cycling within grassland ecosystems. We investigated how aboveground foraging mammalian and invertebrate herbivores affect mineral soil decomposition rates and associated soil properties in two subalpine vegetation types (shortgrass and tall-...

  1. Human disturbance provides foraging opportunities for birds in primary subalpine forest

    DEFF Research Database (Denmark)

    DuBay, Shane G.; Hart Reeve, Andrew; Wu, Yongjie

    2017-01-01

    to species that naturally occur in edge, open, or disturbed habitats. With observations and experiments we provide evidence of insectivorous birds exploiting human disturbance in primary subalpine forest in the mountains of southern China, displaying behavioral flexibility to gain novel foraging...

  2. Net primary productivity of subalpine meadows in Yosemite National Park in relation to climate variability

    Science.gov (United States)

    Peggy E. Moore; Jan W. van Wagtendonk; Julie L. Yee; Mitchel P. McClaran; David N. Cole; Neil K. McDougald; Matthew L. Brooks

    2013-01-01

    Subalpine meadows are some of the most ecologically important components of mountain landscapes, and primary productivity is important to the maintenance of meadow functions. Understanding how changes in primary productivity are associated with variability in moisture and temperature will become increasingly important with current and anticipated changes in climate....

  3. Drought-driven disturbance history characterizes a southern Rocky Mountain subalpine forest

    Science.gov (United States)

    R. Justin DeRose; James N. Long

    2012-01-01

    The view that subalpine forest vegetation dynamics in western North America are "driven" by a particular disturbance type (i.e., fire) has shaped our understanding of their disturbance regimes. In the wake of a recent (1990s) landscape- extent spruce beetle (Dendroctonus rufipennis Kirby) outbreak in the southern Rocky Mountains, we re-examined the temporal...

  4. Water use patterns of three species in subalpine forest, Southwest China: the deuterium isotope approach

    Science.gov (United States)

    Qing Xu; Harbin Li; Jiquan Chen; Jiquan Cheng; Xiaoli Cheng; Shirong Liu; Shuqing An

    2011-01-01

    Determination of water sources of plant species in a community is critical for understanding the hydrological processes and their importance in ecosystem functions. Such partitioning of plant xylem water into specific sources (i.e. precipitation, groundwater) can be achieved by analyzing deuterium isotopic composition (δD) values for source waters. A subalpine dark...

  5. Comparison of the abundance and composition of litter fauna in tropical and subalpine forests

    Science.gov (United States)

    G. Gonzalez; T.R. Seastedt

    2000-01-01

    In this study, we quantify the abundance and composition of the litter fauna in dry and wet tropical forests and north- and south-facing subalpine forests. We used the same litter species contained in litterbags across study sites to standardize for substrate conditions, and a single method of fauna extraction from the litter (Tullgren method). Fauna densities were...

  6. Human-Related Forest Fires in the Subalpine Belt of the Spanish Pyrenees

    Science.gov (United States)

    Sanjuán, Yasmina; María García-Ruiz, José; Beguería, Santiago; Serrano-Muela, María Pilar; González-Sampériz, Penélope; Valero-Garcés, Blas; Arnáez, José

    2014-05-01

    The subalpine belt of the Central Pyrenees ranges approximately between 1700 and 2200 m a.s.l. This area should be covered with dense forests of Pinus sylvestris and P. uncinata, with increasingly open formations towards the upper forest limit. At present, most of the subalpine belt is occupied with grasslands due to human-induced deforestation for enlarging the area occupied by summer pastures. Two are the most important scientific problems related to deforestation of the subalpine belt: (i) the timing of deforestation, and (ii) the geomorphic consequences of a sudden substitution of forests by grasslands. Up to now, intense deforestation is clearly recorded in regional palaeoenvironmental sequences since the Middle Ages and, traditionally, this practice was usually attributed to large fires with the purpose of balance the winter and summer pasture resources. Nevertheless, the presence of abundant remnants of prehistoric monuments (dolmens, cromlechs, tumulus) in the subalpine belt induced to think in a previous seasonal presence of human populations, most probably practicing some primitive type of transhumance. This would only be possible if part of the subalpine forests would be burnt to allow a limited expansion of grasslands, despite the consequences in the landscape of this kind of practices were not permanent in time. We present here new dates of fire occurrence from charcoal obtained from soils in the hillslopes and from lacustrine sediments. Two periods of human-induced fires have been identified: (i) between 2500 and 2000 cal. yr BP, and (ii) between 1100 and 900 cal yr BP. The consequences of deforestation can be easily observed in the landscape, particularly shallow landslide activity, gelifluction, solifluction and the rapid development of parallel incisions in the steepest slopes.

  7. Manipulation of subalpine and alpine microclimate in the Alpine Treeline Warming Experiment

    Science.gov (United States)

    Kueppers, L. M.; Moyes, A. B.; Ferrenberg, S. M.; Christianson, D. S.; Castanha, C.; Germino, M. J.

    2011-12-01

    To experimentally test model projections of subalpine tree species' uphill migration with climate change, we have established the Alpine Treeline Warming Experiment at Niwot Ridge, CO. Common gardens subject to full factorial warming and watering experiments are replicated across three sites: near the lower limit of subalpine forest, within the alpine-treeline ecotone, and in the alpine tundra, beyond the current elevation ranges of the species. In 2010, differences in ambient climate among the three sites included 5.1° C greater growing-season air temperature and 0.5 kPa greater vapor pressure deficit in the lowest compared to the upper two sites. The lower subalpine site also experienced lower soil moisture compared to the upper two sites. Snowmelt date varied substantially between sites, with the longest snow-free period in the lower subalpine site and the shortest in the treeline site. In all sites, we observed advances in the timing of snowmelt in heated relative to control plots. The warming treatment also raised 5 cm soil temperatures by 3° C at the lower subalpine site, and by 1° C in the upper two sites, averaged over the growing season. More substantial wind in the alpine diminished the heating effect through sensible heat loss. Seasonal average volumetric soil moisture at 5-10 cm did not vary strongly among treatments even though seedling survival and gas exchange data suggest that water additions alleviated drought stress in some plots. These preliminary findings for identical warming and watering treatments across our three high mountain sites suggest that microclimate responses vary with radiation environment, patterns of snow accumulation, and wind speed. Some of these differences are realistic for a future warmer world, while others are artifacts of the experimental approach. Microclimate differences in 2011 reflect modified heating methods and a different spring hydroclimate (later snow accumulation and melt), highlighting the importance of

  8. A Comparison of Infrared Gas Analyzers Above a Subalpine Forest

    Science.gov (United States)

    Burns, S. P.; Metzger, S.; Blanken, P.; Burba, G. G.; Swiatek, E.; Li, J.; Conrad, B.

    2014-12-01

    Infrared gas analyzers (IRGAs) are a key component in theeddy-covariance measurement of water vapor and carbon dioxide exchangebetween the surface and atmosphere. Historically, closed-path IRGAshave been used for the fast (> 10 Hz) measurement of atmospheric H2Oand CO2. In order to use them in the field, these IRGAs were typicallyhoused in temperature-controlled enclosures or buildings that weretens of meters away from the measurement location. This necessitatedthe use of long tubing and pumps to bring the air sample to the IRGAcell. Attenuation of H2O and CO2 fluctuations within the tubing was apersistent problem with such a setup, especially for H2O. As analternative, open-path IRGAs have frequently been utilized, but thekey trade-offs with the open-path design are: (i) precipitation anddew-related data gaps, and (ii) the need to account for WPL densityeffects. Over the past five years a new type of closed-path IRGA hasemerged which is weather-proof, compact, and low-maintenance. Becauseof its small size, short intake tubing can be used, which places thesampling cell close to the sonic anemometer and reduces high frequencysignal loss. Two such IRGAs are the LI-COR LI-7200 and the CampbellScientific EC155, which is part of the CPEC200 eddy covariance system.The Niwot Ridge AmeriFlux tower has used a LI-COR LI-6262 IRGA tomeasure CO2 fluxes above a subalpine forest since November, 1998.Starting in summer 2013, a LI-7200 (along with an open-path LI-7500)were deployed at 21.5 m on the AmeriFlux tower. In Fall 2013, aEC155/CPEC200 was added so that a side-by-side comparison between allfour IRGAs was possible. The preliminary results presented in ourstudy compare the CO2 and H2O mean and variance measured by each IRGA,the vertical wind statistics from three side-by-side sonicanemometers, as well as the corresponding spectra and cospectra fromthese sensors as well as other important aspects of systemperformance.

  9. A next-generation sequencing method for overcoming the multiple gene copy problem in polyploid phylogenetics, applied to Poa grasses

    Directory of Open Access Journals (Sweden)

    Robin Charles

    2011-03-01

    Full Text Available Abstract Background Polyploidy is important from a phylogenetic perspective because of its immense past impact on evolution and its potential future impact on diversification, survival and adaptation, especially in plants. Molecular population genetics studies of polyploid organisms have been difficult because of problems in sequencing multiple-copy nuclear genes using Sanger sequencing. This paper describes a method for sequencing a barcoded mixture of targeted gene regions using next-generation sequencing methods to overcome these problems. Results Using 64 3-bp barcodes, we successfully sequenced three chloroplast and two nuclear gene regions (each of which contained two gene copies with up to two alleles per individual in a total of 60 individuals across 11 species of Australian Poa grasses. This method had high replicability, a low sequencing error rate (after appropriate quality control and a low rate of missing data. Eighty-eight percent of the 320 gene/individual combinations produced sequence reads, and >80% of individuals produced sufficient reads to detect all four possible nuclear alleles of the homeologous nuclear loci with 95% probability. We applied this method to a group of sympatric Australian alpine Poa species, which we discovered to share an allopolyploid ancestor with a group of American Poa species. All markers revealed extensive allele sharing among the Australian species and so we recommend that the current taxonomy be re-examined. We also detected hypermutation in the trnH-psbA marker, suggesting it should not be used as a land plant barcode region. Some markers indicated differentiation between Tasmanian and mainland samples. Significant positive spatial genetic structure was detected at Conclusions Our results demonstrate that 454 sequencing of barcoded amplicon mixtures can be used to reliably sample all alleles of homeologous loci in polyploid species and successfully investigate phylogenetic relationships among

  10. Prenatal exposure of testosterone prevents SDN-POA neurons of postnatal male rats from apoptosis through NMDA receptor.

    Science.gov (United States)

    Hsu, H K; Yang, R C; Shih, H C; Hsieh, Y L; Chen, U Y; Hsu, C

    2001-11-01

    The role of N-methyl-D-aspartate (NMDA) receptor in mediating the effect of testosterone exposure prenatally on neuronal apoptosis in the sexual dimorphic nucleus of the preoptic area (SDN-POA) of rats was studied. The endogenous testosterone was diminished by prenatal stress (PNS) or simulated by testosterone exposure (TE) to understand the effect of testosterone on NR(1) (a functional subunit protein of NMDA receptor) expression and neuronal apoptosis. To further study whether the testosterone, after being converted into estradiol, modulates NR(1) expression, 4-androstein-4-ol-3,17-dione (ATD; an aromatase inhibitor) was used to block the conversion of estradiol from testosterone. The expressions of the NR(1) mRNA and NR(1) subunit protein were quantified by RT-PCR and western blotting analysis, respectively. In addition, a noncompetitive antagonist of NMDA receptor, MK-801, was used to find out whether blockage of NMDA receptor affects the naturally occurring apoptosis in SDN-POA. The results showed the following. 1) Expression of perinatal NR(1) subunit protein in the central part of the medial preoptic area of male rats was significantly higher than that of females, especially on postnatal days 1 and 3. 2) The testosterone level of male fetuses on embryonic day 18 was significantly higher than that of females, while the testosterone level of TE females or PNS males was similar to that of intact males or intact females, respectively. 3) The apoptotic incidence of intact male rats was significantly less than that of females, and the apoptosis was stimulated by PNS in male or inhibited by TE in female. 4) The expression of NR(1) subunit protein could be inhibited by PNS or ATD-treatment in male, while stimulated by TE in female. 5) NR(1) mRNA showed no significant difference among intact male, PNS male, ATD-treated male, TE female and intact female rats. 6) The low apoptotic incidence of male rats was significantly increased when NMDA receptor was blocked by MK

  11. La tectónica alpina en el borde norte del Sistema Central español y su enlace con la cuenca del Duero

    Directory of Open Access Journals (Sweden)

    Gómez Ortiz, D.

    1997-12-01

    Full Text Available This report is focused to describe the main alpine structures located in the northern edge of the Spanish Central System and the linking zone with the Tertiary Duero basin. A review of the main characteristics of the alpine tectonic phases is given. From these data, differences between the Gredos zone, dominated by N-S and E-W faults, and the Guadarrama zone, in which N 70° E reverse faults with N 140° E and N 10° E strike-slip faults are present, can be observed. The pattern of drainage of this area shows three main orientations, coincident with the alpine faults activated during the Guadarrama tectonic phase, which reveals the relationship between the present drainage pattern and the Alpine orogeny.En este trabajo se describen las principales estructuras alpinas del borde norte del Sistema Central y su enlace con la cuenca del Duero, así como las características de las principales fases tectónicas alpinas que han dado lugar a la actual estructura. Se pone de manifiesto las diferencias entre la zona de Gredos, dominada por fallas N-S y E-O principalmente, y la zona de Guadarrama en la que las fallas inversas son N 70° E acompañadas de desgarres N 140° E y N 10° E. El análisis de las direcciones de los ríos en este área permite definir tres zonas en función de su orientación, que coinciden con las definidas para las fallas alpinas, lo que refleja la relación entre la red de drenaje y la fase alpina Guadarrama principalmente.

  12. Improving the Efficiency of Homologous Gene Replacement by Disrupting the NHEJ Pathway for Gene KusA in the Oleaginous Fungus Mortierella alpina

    Science.gov (United States)

    Krueger, Kathleen; Dai, Ziyu; Uzuner, Uger

    2012-11-01

    Mortierella alpina, a oleaginous filamentous fungus, is one of industrial fungal strains known for the production of arachidonic acid. It is also of particular interest for hydrocarbon biofuel production since it is able to produce up to 50% of its mass in rich, long-chain polyunsaturated fatty acids [PUFA's]. In addition to high fatty acid production, M. alpina like many other oleaginous fungi, already have mechanisms for accumulating significant concentrations of hydrophobic compounds making it a naturally equipped candidate to handle potential toxic concentrations of hydrocarbons. The goal of this study was to develop an efficient transformation method for this strain, hence allowing researchers to further manipulate these fungi for further improvement of lipid production. Included was optimization of best culture medium for growth and maintenance, optimal conditions for protoplast generation, and replacement of the homologous KusA gene. A successful deletion of KusA gene within biotechnologically important M. alpina could enable homologous recombination of other genes of interest in a higher frequency. This capacity may also improve the advancing the production of microbial oils for bioenergy and arachidonic acid human health applications.

  13. Sorption of O 3, SO 2, NO 2 or their mixture by nine Poa pratensis cultivars of differing pollutant sensitivity

    Science.gov (United States)

    Elkiey, T.; Ormrod, D. P.

    Plants of nine Kentucky bluegrass ( Poa pratensis L.) cultivars were exposed to O 3, SO 2, NO 2 or a mixture of the three gases for three days to determine absorption and adsorption rates of each gas. Absorption rates into stomates differed among cultivars and generally decreased with longer exposure. Leaves of insensitive cultivars generally absorbed less of the single gases than those of sensitive cultivars. There was less absorption of each gas from the mixture than from the single gases. Adsorption rates on leaf surfaces were not always related to cultivar sensitivity and generally decreased less than did adsorption rates with longer exposure. Adsorption rates of O 3 were higher from the single than from mixed gas exposure and of SO 2 were similar from either single or mixed exposure, while the higher rate of NO 2 adsorption, whether from single or mixed gases, varied with cultivar.

  14. Phosphatase activity of Poa pratensis seeds. II. Purification and characterization of acid phosphatase Ia2 and Ia3

    Directory of Open Access Journals (Sweden)

    I. Lorenc-Kubis

    2015-01-01

    Full Text Available Two acid phosphatases (Ia2, Ia3 have been isolated from Poa pratensis seeds and partially purified. Both enzymes showed maximal activity at pH 4,9. They exhibited high activity towards p-nitrophenyl phosphate, inorganic pyrophosphate and phenyl phosphate, much less activity towards glucose-6 phosphate, and mononucleotides. Phosphatases a2 and a3 differed in their activity towards ADP. Orthophosphate, fluoride and Zn2+ were effective inhibitors. EDTA, β-mercaptoethanol and Mg2+ activated phophatase a2 but had no effect on phosphatase a3. Zn2+ inhibited the activity of phosphatase a2 noncompetitively, whereas phosphatase a3 showed inhibition of mixed type. Trypsin, chymotrypsin and pronase had no effect on the enzyme activities of both molecular forms.

  15. Fructan accumulation and transcription of candidate genes during cold acclimation in three varieties of Poa pratensis

    DEFF Research Database (Denmark)

    Rao, R Shyama Prasad; Andersen, Jeppe Reitan; Dionisio, Giuseppe

    2011-01-01

    to different environments: Northern Norway, Denmark, and the Netherlands. Fructan content increased significantly during cold acclimation and varieties showed significant differences in the level of fructan accumulation. cDNA sequences of putative fructosyltransferase (FT), fructan exohydrolase (FEH), and cold......Poa pratensis, a type species for the grass family (Poaceae), is an important cool season grass that accumulates fructans as a polysaccharide reserve. We studied fructan contents and expression of candidate fructan metabolism genes during cold acclimation in three varieties of P. pratensis adapted...... have previously been suggested to be involved in fructan biosynthesis and freezing tolerance, and induced expression of PpFEH during fructan accumulation could also suggest a role in fructan biosynthesis. However, based on the different PpFEH transcription rates among varieties and similar expression...

  16. Leaf waxes of slow-growing alpine and fast-growing lowland Poa species: inherent differences and responses to UV-B radiation

    NARCIS (Netherlands)

    Pilon, J.; Lambers, H.; Baas, W.; Tosserams, M.; Rozema, J.J.; Atkin, O.K.

    1999-01-01

    We investigated whether alpine and lowland Poa species exhibit inherent differences in leaf cuticular waxes, leaf UV absorbing compounds and/or growth responses to UV-B treatment. All plants were grown hydroponically in a growth cabinet (constant 20°; 14 hr photoperiod; 520 mol photons m-2 s-1 PAR).

  17. Leaf waxes of slow-growing alpine and fast-growing lowland Poa species: inherent differences and responses to UV-B radiation.

    NARCIS (Netherlands)

    Pilon, J.J.; Lambers, H.; Baas, W; Tosserams, M.; Rozema, J.; Atkin, O.K.

    1999-01-01

    We investigated whether alpine and lowland Poa species exhibit inherent differences in leaf cuticular waxes, leaf UV absorbing compounds and/or growth responses to UV-B treatment. All plants were grown hydroponically in a growth cabinet (constant 20°; 14 hr photoperiod; 520 μmol photons m

  18. Holocene vegetation and fire regimes in subalpine and mixed conifer forests, southern Rocky Mountains, USA

    Science.gov (United States)

    Anderson, R. Scott; Allen, Craig D.; Toney, J.L.; Jass, R.B.; Bair, A.N.

    2008-01-01

    Our understanding of the present forest structure of western North America hinges on our ability to determine antecedent forest conditions. Sedimentary records from lakes and bogs in the southern Rocky Mountains of Colorado and New Mexico provide information on the relationships between climate and vegetation change, and fire history since deglaciation. We present a new pollen record from Hunters Lake (Colorado) as an example of a high-elevation vegetation history from the southern Rockies. We then present a series of six sedimentary records from ???2600 to 3500-m elevation, including sites presently at the alpine?subalpine boundary, within the Picea engelmannii?Abies lasiocarpa forest and within the mixed conifer forest, to determine the history of fire in high-elevation forests there. High Artemisia and low but increasing percentages of Picea and Pinus suggest vegetation prior to 13 500 calendar years before present (cal yr BP) was tundra or steppe, with open spruce woodland to ???11 900 cal yr BP. Subalpine forest (Picea engelmannii, Abies lasiocarpa) existed around the lake for the remainder of the Holocene. At lower elevations, Pinus ponderosa and/or contorta expanded 11 900 to 10 200 cal yr BP; mixed conifer forest expanded ???8600 to 4700 cal yr BP; and Pinus edulis expanded after ???4700 cal yr BP. Sediments from lake sites near the alpine?subalpine transition contained five times less charcoal than those entirely within subalpine forests, and 40 times less than bog sites within mixed conifer forest. Higher fire episode frequencies occurred between ???12 000 and 9000 cal yr BP (associated with the initiation or expansion of south-west monsoon and abundant lightning, and significant biomass during vegetation turnover) and at ???2000?1000 cal yr BP (related to periodic droughts during the long-term trend towards wetter conditions and greater biomass). Fire episode frequencies for subalpine?alpine transition and subalpine sites were on average 5 to 10 fire

  19. Variation in winter snowpack depth and duration influences summer soil respiration in a subalpine meadow

    Science.gov (United States)

    Arnold, C. L.; Ghezzehei, T. A.; Berhe, A. A.

    2012-12-01

    Subalpine meadows in the Sierra Nevada rely on the depth and duration of the winter snowpack to supply ample water to restore the water table in the meadow during the spring snowmelt. This study examines the role that interannual variability in the winter snowpack plays in the overall rate of summer soil respiration along a hydrologic gradient in a subalpine meadow. Carbon dioxide efflux from the meadow was measured from June through September in 2011 and 2012 using soil collars and a LICOR 8100A infrared gas analyzer. Preliminary results show that soil respiration rates are influenced by the hydrologic gradient across the meadow, with drier regions peaking earlier in the summer as compared to wetter regions. We also show that high snowpack years can suppress soil respiration in the meadow until late in the summer season as compared to low snowpack years, where soil respiration peaks early in the summer.

  20. Phenology of plants in relation to ambient environment in a subalpine forest of Uttarakhand, western Himalaya

    OpenAIRE

    Bisht, Vinod K.; Kuniyal, Chandra P.; Bhandari, Arvind K.; Nautiyal, Bhagwati P.; Prasad, P.

    2014-01-01

    Observations on phenology of some representative trees, shrubs, under-shrubs and herbs in a subalpine forest of Uttarakhand, western Himalaya were recorded. With the commencement of favorable growth season in April, occurrence of leaf fall was indicatory growth phenomenon in Quercus semecarpifolia, Q. floribunda and Abies spectabilis. However, active vegetative growth in herbaceous species starts onward April and fruit maturation and seed dehiscence are completed from mid of September to Octo...

  1. Bleaching of leaf litter and associated microfungi in subboreal and subalpine forests.

    Science.gov (United States)

    Hagiwara, Yusuke; Matsuoka, Shunsuke; Hobara, Satoru; Mori, Akira S; Hirose, Dai; Osono, Takashi

    2015-10-01

    Fungal decomposition of lignin leads to the whitening, or bleaching, of leaf litter, especially in temperate and tropical forests, but less is known about such bleaching in forests of cooler regions, such as boreal and subalpine forests. The purposes of the present study were to examine the extent of bleached area on the surface of leaf litter and its variation with environmental conditions in subboreal and subalpine forests in Japan and to examine the microfungi associated with the bleaching of leaf litter by isolating fungi from the bleached portions of the litter. Bleached area accounted for 21.7%-32.7% and 2.0%-10.0% of total leaf area of Quercus crispula and Betula ermanii, respectively, in subboreal forests, and for 6.3% and 18.6% of total leaf area of B. ermanii and Picea jezoensis var. hondoensis, respectively, in a subalpine forest. In subboreal forests, elevation, C/N ratio and pH of the FH layer, and slope aspect were selected as predictor variables for the bleached leaf area. Leaf mass per area and lignin content were consistently lower in the bleached area than in the nonbleached area of the same leaves, indicating that the selective decomposition of acid unhydrolyzable residue (recalcitrant compounds such as lignin, tannins, and cutins) enhanced the mass loss of leaf tissues in the bleached portions. Isolates of a total of 11 fungal species (6 species of Ascomycota and 5 of Basidiomycota) exhibited leaf-litter-bleaching activity under pure culture conditions. Two fungal species (Coccomyces sp. and Mycena sp.) occurred in both subboreal and subalpine forests, which were separated from each other by approximately 1100 km.

  2. The influence of chemoreception on the foraging behaviour of two species of sandpiper, calidris alba and calidris alpina

    Science.gov (United States)

    Van Heezik, Y. M.; Gerritsen, A. F. C.; Swennen, C.

    This study is concerned with the ability of two wader species, the sanderling, Calidris alba and the dunlin, C. alpina to determine the presence of prey in a sediment by using their sense of taste, and whether they use this information while foraging for prey hidden in the sediment. Preference tests were designed in which the birds were presented with a choice of 2 jars filled with sand from 3 possible combination pairs: (1) "food" and "no taste", (2) "food" and "taste", and (3) "taste" and "no taste". Preferences were measured as the relative amount of time spent foraging in each jar of each pair. Significantly more time was spent on "taste" than on "no taste" for the "taste" and "no taste" combination. More time was spent on "taste" than on "no taste" when each was paired with "food" for 3 out of 4 situations. Foraging technique on "taste" was observed to be more purposeful and methodical than on "no taste". Both species are shown to be able to use taste while foraging to determine whether prey is present, and can modify their foraging behaviour by persisting in a spot that gives no information on the presence of prey other than taste, and by using a different, more determined searching technique.

  3. Establishment of an overall transformation system for an oil-producing filamentous fungus, Mortierella alpina 1S-4.

    Science.gov (United States)

    Takeno, Seiki; Sakuradani, Eiji; Murata, Shoichi; Inohara-Ochiai, Misa; Kawashima, Hiroshi; Ashikari, Toshihiko; Shimizu, Sakayu

    2004-09-01

    Oil-producing fungus Mortierella alpina 1S-4 is an industrial strain. To determine its physiological properties and to clarify the biosynthetic pathways for polyunsaturated fatty acids, a transformation system for this fungus was established using a derivative of it, i.e., a ura5- mutant lacking orotate phosphoribosyl transferase (OPRTase, EC.2.4.2.10) activity. Transformation with a vector containing the homologous ura5 gene as a marker was successfully performed using microprojectile bombardment, other methods frequently used for transformation, such as the protoplasting, lithium acetate, or electroporation methods, not giving satisfactory results. As a result, two types of transformants were obtained: a few stable transformants overexpressing the ura5 gene, and many unstable transformants showing OPRTase activity comparable to that of the wild-type strain. The results of quantitative PCR indicated that the stable transformants could retain the ura5 genes originating from the transformation vector regardless of the culture conditions. On the other hand, unstable transformants easily lost the marker gene under uracil-containing conditions, as expected. In this paper, we report that an overall transformation system for this fungus was successfully established, and propose how to select useful transformants as experimental and industrial strains.

  4. Semivolatile POA and parameterized total combustion SOA in CMAQv5.2: impacts on source strength and partitioning

    Directory of Open Access Journals (Sweden)

    B. N. Murphy

    2017-09-01

    Full Text Available Mounting evidence from field and laboratory observations coupled with atmospheric model analyses shows that primary combustion emissions of organic compounds dynamically partition between the vapor and particulate phases, especially as near-source emissions dilute and cool to ambient conditions. The most recent version of the Community Multiscale Air Quality model version 5.2 (CMAQv5.2 accounts for the semivolatile partitioning and gas-phase aging of these primary organic aerosol (POA compounds consistent with experimentally derived parameterizations. We also include a new surrogate species, potential secondary organic aerosol from combustion emissions (pcSOA, which provides a representation of the secondary organic aerosol (SOA from anthropogenic combustion sources that could be missing from current chemical transport model predictions. The reasons for this missing mass likely include the following: (1 unspeciated semivolatile and intermediate volatility organic compound (SVOC and IVOC, respectively emissions missing from current inventories, (2 multigenerational aging of organic vapor products from known SOA precursors (e.g., toluene, alkanes, (3 underestimation of SOA yields due to vapor wall losses in smog chamber experiments, and (4 reversible organic compounds–water interactions and/or aqueous-phase processing of known organic vapor emissions. CMAQ predicts the spatially averaged contribution of pcSOA to OA surface concentrations in the continental United States to be 38.6 and 23.6 % in the 2011 winter and summer, respectively. Whereas many past modeling studies focused on a particular measurement campaign, season, location, or model configuration, we endeavor to evaluate the model and important uncertain parameters with a comprehensive set of United States-based model runs using multiple horizontal scales (4 and 12 km, gas-phase chemical mechanisms, and seasons and years. The model with representation of semivolatile POA

  5. Semivolatile POA and parameterized total combustion SOA in CMAQv5.2: impacts on source strength and partitioning

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, Benjamin N.; Woody, Matthew C.; Jimenez, J. L.; Carlton, A. G.; Hayes, Patrick; Liu, Shang; Ng, Nga L.; Russell, Lynn M.; Setyan, Ari; Xu, Lu; Young, Jeff; Zaveri, Rahul A.; Zhang, Qi; Pye, Havala O.

    2017-09-20

    Mounting evidence from field and laboratory observations coupled with atmospheric model analyses show that primary combustion emissions of organic compounds dynamically partition between the vapor and particulate phases, espe-cially as near-source emissions dilute and cool to ambient conditions. The most recent version of the Community Multiscale Air Quality (CMAQ) Model v5.2 accounts for the semivolatile partitioning and gas-phase aging of these primary organic aerosol (POA) compounds consistent with experimentally derived parameterizations. We also include a new surrogate species, potential secondary organic aerosol from combustion emissions (pcSOA), which provides a representation of the SOA from an-thropogenic combustion sources that could be missing from current chemical transport model predictions. The reasons for this missing mass likely include the following: 1) unspeciated semivolatile and intermediate volatility organic compound (SVOC and IVOC, respectively) emissions missing from current inventories, 2) multigenerational aging of organic vapor products from known SOA precursors (e.g. toluene, alkanes, etc), 3) underestimation of SOA yields due to vapor wall losses in smog chamber experiments, and 4) reversible organic-water interactions and/or aqueous-phase processing of known organic vapor emissions. CMAQ predicts the spatially-averaged contribution of pcSOA to OA surface concentrations in the continental United States to be 38.6% and 23.6% in the 2011 winter and summer, respectively. Whereas many past modeling studies focused on a particular measurement campaign, season, location, or model configuration, we endeavor to evaluate the model and important uncertain parameters with a comprehensive set of United States-based model runs using multiple horizontal scales (4 km and 12 km), gas-phase chemical mechanisms, seasons and years. The model with representation of semivolatile POA improves predictions of hourly OA observations over the traditional

  6. Parâmetros genéticos para a produção de leite em caprinos das raças Saanen e Alpina Genetic parameters for milk yield in Saanen and Alpina breed goats

    Directory of Open Access Journals (Sweden)

    Natália Irano

    2012-06-01

    Full Text Available Objetivou-se com este trabalho estimar parâmetros genéticos para a produção de leite acumulada até os 305 dias (P305 de cabras das raças Saanen e Alpina. Foram utilizadas as duas primeiras parições de cabras pertencentes a rebanhos participantes do programa de controle produtivo e reprodutivo de caprinos (PROCAPRI da UNESP-FCAV-Jaboticabal-SP. A P305 foi analisada por meio de modelos de repetibilidade e bicaracterísticas. Para verificar a influência dos efeitos fixos sobre a característica analisada foram realizadas análises preliminares, pelo método de quadrados mínimos. Os componentes de covariâncias foram estimados pelo método da máxima verossimilhança restrita (REML, utilizando o programa Wombat. A duração da lactação, a idade da cabra ao parto, o rebanho, o ano de parto e a estação de parto foram importantes fontes de variação para a P305. Não houve diferença significativa entre as raças estudadas. As estimativas de herdabilidade e repetibilidade para a P305, obtidas com o modelo de repetibilidade, foram de 0,29 e 0,36, respectivamente. As estimativas de herdabilidade, obtidas pelos modelos de repetibilidade e bicaracterísticas foram semelhantes. Sendo assim, um modelo de repetibilidade poderia ser indicado para avaliar a P305 pela sua simplicidade.The objective of this study was to estimate genetic parameters for 305 days milk yield (M305 in Saanen and Alpina breed goats. Data consisted of records from first to second lactations of goats belonging to herds participating in the program control productive and reproductive goats (PROCAPRI from UNESP-FCAV-Jaboticabal-SP. The M305 was analyzed by repeatability and bi-trait models. The influence of fixed effects on the traits was analyzed preliminary analysis by the method of least squares. Variance components were estimated by restricted maximum likelihood method (REML, using the package Wombat. The duration of lactation, age of dam at calving, the herd, calving

  7. Zabrocki’s structural phonetics in the case study of velar POA assimilation in Latinate prefixation in RP English

    Directory of Open Access Journals (Sweden)

    Haładewicz-Grzelak Małgorzata

    2014-12-01

    Full Text Available Zabrocki understood structural phonetics as a branch of phonetics concerned with analyzing acodal (substantial systems (cf. Bańczerowski 1980: 13. In this theory, each sound has a specific acoustic and articulatory substance. Zabrocki constructed linear substantial sound structures based on measuring the amount of substance implied in the articulation. Diachronic structural phonetics, in turn, is the application of synchronically defined phonetic and acoustic relations to the study of language change. This paper investigates a synchronic scenario for velar POA assimilation in Latinate prefixation in English and tests the findings against the tenets of Zabrocki’s theory. The results show that Zabrocki’s structural phonetics perfectly accounts for the empirical findings. The corpus of investigation is comprised of realizations of all RP English Latinate prefixes ending with /n/, collected from various pronunciation dictionaries (online and paper. As a collateral corpus, recordings of two native speakers of English were made in which they produced some of the corpus material, as well as nonce words and unusual lexemes not listed in pronunciation dictionaries

  8. Altered sexually dimorphic nucleus of the preoptic area (SDN-POA) volume in adult Long-Evans rats by dietary soy phytoestrogens.

    Science.gov (United States)

    Lund, T D; Rhees, R W; Setchell, K D; Lephart, E D

    2001-09-28

    Naturally occurring estrogen-like molecules in plants (phytoestrogens), present via soy, in animal diets can alter morphology and physiology in rodents. Phytoestrogens have the ability to bind estrogen receptors and exert many of the biological responses evoked by physiological estrogens. This study characterized the effects of dietary phytoestrogens on the expression of body and prostate weight, circulating testosterone and estradiol levels, puberty onset, vaginal cyclicity, and volume of the sexually dimorphic nucleus of the preoptic area (SDN-POA) in Long-Evans rats. Using different experimental protocols, animals were fed either a phytoestrogen-rich (Phyto-600) or a phytoestrogen-free (Phyto-free) diet. Animals fed the Phyto-600 diet displayed significantly decreased body weights (in males and females), prostate weights and delayed puberty in females compared to that of animals fed the Phyto-free diet. Circulating testosterone or estradiol levels in males or estrous cyclicity were not altered by the diets. The volume of the SDN-POA was significantly altered by a change in diet at 80 days of age where one-half of the males or females fed the Phyto-600 diet (from birth) were switched to the Phyto-free diet until 120 days of age. Males initially fed a Phyto-600 diet but changed to a Phyto-free diet had significantly smaller SDN-POA volumes compared to males fed the Phyto-600 diet (long-term). These data suggest that consumption of phytoestrogens via a soy diet, significantly: (1) decreases body and prostate weight, (2) delays puberty onset, and (3) alters SDN-POA volumes during adulthood.

  9. Measuring patient and visitor violence in general hospitals: feasibility of the SOVES-G-R, internal consistency and construct validity of the POAS-S and the POIS.

    Science.gov (United States)

    Hahn, Sabine; Müller, Marianne; Needham, Ian; Dassen, Theo; Kok, Gerjo; Halfens, Ruud Jg

    2011-09-01

    To investigate the feasibility of a survey measuring patient and visitor violence after translation and modification, namely the Survey of Violence Experienced by Staff (German version revised) and to validate the shortened Perception of Aggression Scale (POAS-S) and the Perception of Importance of Intervention Skills Scale (POIS) after adaptation for use in a general hospital setting. The use of different approaches and research instruments for investigating patient and visitor violence negatively influences the comparability of studies. Typically, general hospitals use self-administered surveys. However, support for these instruments' validity is insufficient. Between November 2006-January 2007, 291 nurses working in general hospitals in the German-speaking region of Switzerland completed the SOVES-G-R, the POAS-S and the POIS (response rate=71%). Results. The participants' responses demonstrated a need for modifications to enhance the feasibility of the SOVES-G-R in two categories, namely experiences with patient and visitor violence in 'the past 12 months' and in 'the past working week'. The POAS-S revealed the same factor solution as in earlier studies, with two factors explaining 38·0% of variance. In the POIS, two factors were distinguished: (1) structured interventions and evaluation and (2) the importance of preventive measures. The SOVES-G-R, the POAS-S and the POIS are adequate for investigating factors influencing the occurrence of patient and visitor violence in general hospitals. Given the changes in the SOVES-G-R and the moderate size of our sample, further testing with a larger sample is recommended. The instruments help determine which clinical settings have a greater risk of patient and visitor violence and the specific factors that influence this risk. This can facilitate the implementation of situation-specific preventive measures against patient and visitor violence in general hospitals. © 2011 Blackwell Publishing Ltd.

  10. Endogenous Quantification of Abscisic Acid and Indole-3-Acetic Acid in Somatic and Zigotic Embryos of Nothofagus alpina (Poepp. & Endl. Oerst Cuantificación Endógena de Ácido Abscísico y Ácido Indol-3 Acético en Embriones Somáticos y Cigóticos de Nothofagus alpina (Poepp. & Endl. Oerst

    Directory of Open Access Journals (Sweden)

    Pricila Cartes Riquelme

    2011-12-01

    Full Text Available Abscisic acid (ABA and indole-3-acetic acid (IAA participate in the propagation of plants by somatic embryogenesis, causing polar structural differentiation of the embryo. The goal of the assay was to compare endogenous levels of ABA and IAA between somatic embryos (SE and zygotic embryos (ZE of Nothofagus alpina (Poepp. & Endl. Oerst. In this study, a somatic embryo maturation assay involving the addition of varying concentrations of exogenous ABA was performed on cotyledonary-stage of N. alpina. Furthermore, the endogenous levels of ABA and IAA were quantified in the immature ZE, the mature ZE, and the embryonic axis of a mature embryo of N. alpina. The current study utilized high performance liquid chromatography (HPLC for quantification. The maturation treatments performed did not present significant differences in the endogenous ABA levels in SE. However, significant differences did exist in levels of ABA and IAA between SE submitted to the different maturation treatments and mature ZE of N. alpina. The application of exogenous ABA to the culture medium increased endogenous ABA levels, therefore, increasing the number of germinated somatic embryos. Thus, the plant conversion process was also successfully completed in somatic embryos of N. alpina.El ácido abscísico (ABA y el ácido indol 3 acético (IAA participan en el proceso de propagación de plantas mediante embriogénesis somática, ya que permiten la diferenciación de la estructura polar del embrión, órganos y regiones meristemáticas de éste. En este estudio se llevó a cabo un ensayo de maduración de embriones somáticos en estado cotiledonar con la adición de diferentes concentraciones de ABA exógeno, además se determinaron niveles endógenos entre ZE inmaduro, ZE maduro, y eje embrionario aislado desde el embrión maduro para luego comparar niveles endógenos de ABA e IAA en embriones somáticos (SE y cigóticos (ZE de raulí, Nothofagus alpina (Poepp. & Endl. Oerst. La

  11. Warming and provenance limit tree recruitment across and beyond the elevation range of subalpine forest.

    Science.gov (United States)

    Kueppers, Lara M; Conlisk, Erin; Castanha, Cristina; Moyes, Andrew B; Germino, Matthew J; de Valpine, Perry; Torn, Margaret S; Mitton, Jeffry B

    2017-06-01

    Climate niche models project that subalpine forest ranges will extend upslope with climate warming. These projections assume that the climate suitable for adult trees will be adequate for forest regeneration, ignoring climate requirements for seedling recruitment, a potential demographic bottleneck. Moreover, local genetic adaptation is expected to facilitate range expansion, with tree populations at the upper forest edge providing the seed best adapted to the alpine. Here, we test these expectations using a novel combination of common gardens, seeded with two widely distributed subalpine conifers, and climate manipulations replicated at three elevations. Infrared heaters raised temperatures in heated plots, but raised temperatures more in the forest than at or above treeline because strong winds at high elevation reduced heating efficiency. Watering increased season-average soil moisture similarly across sites. Contrary to expectations, warming reduced Engelmann spruce recruitment at and above treeline, as well as in the forest. Warming reduced limber pine first-year recruitment in the forest, but had no net effect on fourth-year recruitment at any site. Watering during the snow-free season alleviated some negative effects of warming, indicating that warming exacerbated water limitations. Contrary to expectations of local adaptation, low-elevation seeds of both species initially recruited more strongly than high-elevation seeds across the elevation gradient, although the low-provenance advantage diminished by the fourth year for Engelmann spruce, likely due to small sample sizes. High- and low-elevation provenances responded similarly to warming across sites for Engelmann spruce, but differently for limber pine. In the context of increasing tree mortality, lower recruitment at all elevations with warming, combined with lower quality, high-provenance seed being most available for colonizing the alpine, portends range contraction for Engelmann spruce. The lower

  12. Warming and provenance limit tree recruitment across and beyond the elevation range of subalpine forest

    Science.gov (United States)

    Kueppers, Lara M.; Conlisk, Erin; Castanha, Cristina; Moyes, Andrew B.; Germino, Matthew; de Valpine, Perry; Torn, Margaret S.; Mitton, Jeffry B.

    2017-01-01

    Climate niche models project that subalpine forest ranges will extend upslope with climate warming. These projections assume that the climate suitable for adult trees will be adequate for forest regeneration, ignoring climate requirements for seedling recruitment, a potential demographic bottleneck. Moreover, local genetic adaptation is expected to facilitate range expansion, with tree populations at the upper forest edge providing the seed best adapted to the alpine. Here, we test these expectations using a novel combination of common gardens, seeded with two widely distributed subalpine conifers, and climate manipulations replicated at three elevations. Infrared heaters raised temperatures in heated plots, but raised temperatures more in the forest than at or above treeline because strong winds at high elevation reduced heating efficiency. Watering increased season-average soil moisture similarly across sites. Contrary to expectations, warming reduced Engelmann spruce recruitment at and above treeline, as well as in the forest. Warming reduced limber pine first-year recruitment in the forest, but had no net effect on fourth-year recruitment at any site. Watering during the snow-free season alleviated some negative effects of warming, indicating that warming exacerbated water limitations. Contrary to expectations of local adaptation, low-elevation seeds of both species initially recruited more strongly than high-elevation seeds across the elevation gradient, although the low-provenance advantage diminished by the fourth year for Engelmann spruce, likely due to small sample sizes. High- and low-elevation provenances responded similarly to warming across sites for Engelmann spruce, but differently for limber pine. In the context of increasing tree mortality, lower recruitment at all elevations with warming, combined with lower quality, high-provenance seed being most available for colonizing the alpine, portends range contraction for Engelmann spruce. The lower

  13. Resurgence of human bothriocephalosis (Diphyllobothrium latum in the subalpine lake region

    Directory of Open Access Journals (Sweden)

    Renata BOUCHER-RODONI

    2001-02-01

    Full Text Available Human bothriocephalosis is once again being found in various catchment basins in the subalpine region, including Lago Maggiore and Lac Léman, which however are not isolated cases. Domestic animals are thought to be responsible for the survival of the parasite during the period when no human cases were reported. The new phenomenon of eating raw or poorly cooked fish is responsible for the resurgence of human bothriocephalosis, which affects various lake districts in Europe. This habit of eating raw fish might lead to the resurgence of a much more dangerous human parasitosis, transmitted in a similar way: infestation by Anisakis.

  14. Development of a greenhouse-based inoculation protocol for the fungus Colletotrichum cereale pathogenic to annual bluegrass (Poa annua

    Directory of Open Access Journals (Sweden)

    Lisa A. Beirn

    2015-08-01

    Full Text Available The fungus Colletotrichum cereale incites anthracnose disease on Poa annua (annual bluegrass turfgrass. Anthracnose disease is geographically widespread throughout the world and highly destructive to cool-season turfgrasses, with infections by C. cereale resulting in extensive turf loss. Comprehensive research aimed at controlling turfgrass anthracnose has been performed in the field, but knowledge of the causal organism and its basic biology is still needed. In particular, the lack of a reliable greenhouse-based inoculation protocol performed under controlled environmental conditions is an obstacle to the study of C. cereale and anthracnose disease. Our objective was to develop a consistent and reproducible inoculation protocol for the two major genetic lineages of C. cereale. By adapting previously successful field-based protocols and combining with components of existing inoculation procedures, the method we developed consistently produced C. cereale infection on two susceptible P. annua biotypes. Approximately 7 to 10 days post-inoculation, plants exhibited chlorosis and thinning consistent with anthracnose disease symptomology. Morphological inspection of inoculated plants revealed visual signs of the fungus (appressoria and acervuli, although acervuli were not always present. After stringent surface sterilization of inoculated host tissue, C. cereale was consistently re-isolated from symptomatic tissue. Real-time PCR detection analysis based on the Apn2 marker confirmed the presence of the pathogen in host tissue, with both lineages of C. cereale detected from all inoculated plants. When a humidifier was not used, no infection developed for any biotypes or fungal isolates tested. The inoculation protocol described here marks significant progress for in planta studies of C. cereale, and will enable scientifically reproducible investigations of the biology, infectivity and lifestyle of this important grass pathogen.

  15. Development of a greenhouse-based inoculation protocol for the fungus Colletotrichum cereale pathogenic to annual bluegrass (Poa annua).

    Science.gov (United States)

    Beirn, Lisa A; Wang, Ruying; Clarke, Bruce B; Crouch, Jo Anne

    2015-01-01

    The fungus Colletotrichum cereale incites anthracnose disease on Poa annua (annual bluegrass) turfgrass. Anthracnose disease is geographically widespread throughout the world and highly destructive to cool-season turfgrasses, with infections by C. cereale resulting in extensive turf loss. Comprehensive research aimed at controlling turfgrass anthracnose has been performed in the field, but knowledge of the causal organism and its basic biology is still needed. In particular, the lack of a reliable greenhouse-based inoculation protocol performed under controlled environmental conditions is an obstacle to the study of C. cereale and anthracnose disease. Our objective was to develop a consistent and reproducible inoculation protocol for the two major genetic lineages of C. cereale. By adapting previously successful field-based protocols and combining with components of existing inoculation procedures, the method we developed consistently produced C. cereale infection on two susceptible P. annua biotypes. Approximately 7 to 10 days post-inoculation, plants exhibited chlorosis and thinning consistent with anthracnose disease symptomology. Morphological inspection of inoculated plants revealed visual signs of the fungus (appressoria and acervuli), although acervuli were not always present. After stringent surface sterilization of inoculated host tissue, C. cereale was consistently re-isolated from symptomatic tissue. Real-time PCR detection analysis based on the Apn2 marker confirmed the presence of the pathogen in host tissue, with both lineages of C. cereale detected from all inoculated plants. When a humidifier was not used, no infection developed for any biotypes or fungal isolates tested. The inoculation protocol described here marks significant progress for in planta studies of C. cereale, and will enable scientifically reproducible investigations of the biology, infectivity and lifestyle of this important grass pathogen.

  16. Inhibition of Advanced Glycation End-Product Formation and Antioxidant Activity by Extracts and Polyphenols from Scutellaria alpina L. and S. altissima L.

    Science.gov (United States)

    Grzegorczyk-Karolak, Izabela; Gołąb, Krzysztof; Gburek, Jakub; Wysokińska, Halina; Matkowski, Adam

    2016-06-14

    Methanolic extracts from the aerial parts and roots of two Scutellaria species, S. alpina and S. altissima, and five polyphenols from these plants demonstrated a significant ability to inhibit the formation of advanced glycation end-products (AGE) in vitro. S. alpina, which is richer in polyphenolic compounds, had strong antiglycation properties. These extracts demonstrated also high activity in the FRAP (ferric-reducing antioxidant power), antiradical (DPPH) and lipid peroxidation inhibition assays. Among the pure compounds, baicalin was the strongest glycation inhibitor (90.4% inhibition at 100 μg/mL), followed by luteolin (85.4%). Two other flavone glycosides had about half of this activity. Verbascoside was similar to the reference drug aminoguanidine (71.2% and 75.9%, respectively). The strong correlation observed between AGE inhibition and total flavonoid content indicated that flavonoids contribute significantly to antiglycation properties. A positive correlation was also observed between antiglycative and antioxidant activities. The studied skullcap species can be considered as a potential source of therapeutic agents for hyperglycemia-related disorders.

  17. Phylogeny and ecophysiology of opportunistic "snow molds" from a subalpine forest ecosystem.

    Science.gov (United States)

    Schmidt, S K; Wilson, K L; Meyer, A F; Gebauer, M M; King, A J

    2008-11-01

    Mats of coenocytic "snow molds" are commonly observed covering the soil and litter of alpine and subalpine areas immediately following snow melt. Here, we describe the phylogenetic placement, growth rates, and metabolic potential of cold-adapted fungi from under-snow mats in the subalpine forests of Colorado. SSU rDNA sequencing revealed that these fungi belong to the zygomycete orders Mucorales and Mortierellales. All of the isolates could grow at temperatures observed under the snow at our sites (0 degrees C and -2 degrees C) but were unable to grow at temperatures above 25 degrees C and were unable to grow anaerobically. Growth rates for these fungi were very high at -2 degrees C, approximately an order of magnitude faster than previously studied cold-tolerant fungi from Antarctic soils. Given the rapid aerobic growth of these fungi at low temperatures, we propose that they are uniquely adapted to take advantage of the flush of nutrient that occurs at the soil-snow interface beneath late winter snow packs. In addition, extracellular enzyme production was relatively high for the Mucorales, but quite low for the Mortierellales, perhaps indicating some niche separation between these fungi beneath the late winter snow pack.

  18. Subalpine Pyrenees received higher nitrogen deposition than predicted by EMEP and CHIMERE chemistry-transport models

    Science.gov (United States)

    Boutin, Marion; Lamaze, Thierry; Couvidat, Florian; Pornon, André

    2015-08-01

    Deposition of reactive nitrogen (N) from the atmosphere is expected to be the third greatest driver of biodiversity loss by the year 2100. Chemistry-transport models are essential tools to estimate spatially explicit N deposition but the reliability of their predictions remained to be validated in mountains. We measured N deposition and air concentration over the subalpine Pyrenees. N deposition was found to range from 797 to 1,463 mg N m-2 year-1. These values were higher than expected from model predictions, especially for nitrate, which exceeded the estimations of EMEP by a factor of 2.6 and CHIMERE by 3.6. Our observations also displayed a reversed reduced-to-oxidized ratio in N deposition compared with model predictions. The results highlight that the subalpine Pyrenees are exposed to higher levels of N deposition than expected according to standard predictions and that these levels exceed currently recognized critical loads for most high-elevation habitats. Our study reveals a need to improve the evaluation of N deposition in mountains which are home to a substantial and original part of the world’s biodiversity.

  19. Biogeochemical impacts of wildfires over four millennia in a Rocky Mountain subalpine watershed.

    Science.gov (United States)

    Dunnette, Paul V; Higuera, Philip E; McLauchlan, Kendra K; Derr, Kelly M; Briles, Christy E; Keefe, Margaret H

    2014-08-01

    Wildfires can significantly alter forest carbon (C) storage and nitrogen (N) availability, but the long-term biogeochemical legacy of wildfires is poorly understood. We obtained a lake-sediment record of fire and biogeochemistry from a subalpine forest in Colorado, USA, to examine the nature, magnitude, and duration of decadal-scale, fire-induced ecosystem change over the past c. 4250 yr. The high-resolution record contained 34 fires, including 13 high-severity events within the watershed. High-severity fires were followed by increased sedimentary N stable isotope ratios (δ15N) and bulk density, and decreased C and N concentrations--reflecting forest floor destruction, terrestrial C and N losses, and erosion. Sustained low sediment C : N c. 20-50 yr post-fire indicates reduced terrestrial organic matter subsidies to the lake. Low sedimentary δ15N c. 50-70 yr post-fire, coincident with C and N recovery, suggests diminishing terrestrial N availability during stand development. The magnitude of post-fire changes generally scaled directly with inferred fire severity. Our results support modern studies of forest successional C and N accumulation and indicate pronounced, long-lasting biogeochemical impacts of wildfires in subalpine forests. However, even repeated high-severity fires over millennia probably did not deplete C or N stocks, because centuries between high-severity fires allowed for sufficient biomass recovery. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  20. Biological and physical influences on the carbon isotope content of CO2 in a subalpine forest snowpack, Niwot Ridge, Colorado

    Science.gov (United States)

    D. R. Bowling; W. J. Massman; S. M. Schaeffer; S. P. Burns; R. K. Monson; M. W. Williams

    2009-01-01

    Considerable research has recently been devoted to understanding biogeochemical processes under winter snow cover, leading to enhanced appreciation of the importance of many winter ecological processes. In this study, a comprehensive investigation of the stable carbon isotope composition (δ 13C) of CO2 within a high-elevation subalpine...

  1. Survival, frost susceptibility, growth, and disease resistance of corkbark and subalpine fir grown for landscape and Christmas trees

    Science.gov (United States)

    Trees from six corkbark fir (Abies lasiocarpa var. arizonica) and 10 subalpine fir (A. lasiocarpa var. lasiocarpa) seed sources were grown at the University of Idaho Sandpoint Research and Extension Center (SREC) and two commercial nurseries in Idaho and Oregon. Post transplant mortality was highest...

  2. Mean wind patterns and snow depths in an alpine-subalpine ecosystem as measured by damage to coniferous trees

    Science.gov (United States)

    G. L. Wooldridge; R. C. Musselman; R. A. Sommerfeld; D. G. Fox; B. H. Connell

    1996-01-01

    1. Deformations of Engelmann spruce and subalpine fir trees were surveyed for the purpose of determining climatic wind speeds and directions and snow depths in the Glacier Lakes Ecosystem Experiments Site (GLEES) in the Snowy Range of southeastern Wyoming, USA. Tree deformations were recorded at 50- and 100-m grid intervals over areas of c. 30 ha and 300 ha,...

  3. Mycorrhiza-plant colonization patterns on a subalpine glacier forefront as a model system of primary succession

    Science.gov (United States)

    Efren Cazares; James M. Trappe; Ari Jumpponen

    2005-01-01

    Lyman glacier in the North Cascades Mountains of Washington has a subalpine forefront characterized by a well-developed terminal moraine, inconspicuous successional moraines, fluting, and outwash. These deposits were depleted of symbiotic fungi when first exposed but colonized by them over time after exposure. Four major groups of plant species in this system are (1)...

  4. Evaluating the Importance of Plant Functional Traits: the Subalpine and Alpine

    Science.gov (United States)

    Sanchez, A.; Smith, W. K.

    2011-12-01

    Over the past several decades, researchers have attempted to characterize plant groups according to traits that are considered functional, i.e. contributing significantly to fitness. Due to the complexity of measuring fitness, the capability for photosynthetic carbon gain is often used as a proxy. Thus, this approach correlates structural differences to photosynthetic performance, especially those differences that are known to be associated with photosynthesis, are easily measured and inexpensive. At the often sharp boundary between the subalpine forest and alpine community (treeline ecotone), plant structural traits change dramatically, i.e. tall evergreen trees give way abruptly to low-stature shrubs, grasses, forbs, and herbs. Yet, the differences in functional traits, so abundant in the literature for a variety of species and communities, have not been compared contiguous communities such as the subalpine forest and alpine. Can differences in functional traits already identified in the literature also be used to characterize species of these two contrasting communities? Or are there other traits that are most functional and/or, possibly, unique to each community and not the most popular traits reported so far in the literature. Also, does the community structure itself help determine functional traits? For example, the top ten most frequently studied traits (145 total papers from approximately 63 different refereed journals) considered functional include the following (% of the 145 publications): specific leaf area or mass (SLA or SLM 39%), plant height (36%), leaf nitrogen content (34%), leaf size (19%), leaf area (16%), leaf photosynthetic performance (15%), leaf dry matter content (LDMC 15%), leaf mass per unit leaf area (LMA 15%), leaf thickness (15%), and seed mass (14%). In addition, another 120 traits were mentioned as functional, although all fell below a 14% citation rate. Particular focus was placed on this group due to the possibility that they might

  5. LOS DÃAS LARGOS ARTIFICIALES CONSTANTES INCREMENTAN LA PRODUCCIÓN LÃCTEA EN LAS CABRAS ALPINAS DEL NORTE DE MÉXICO

    OpenAIRE

    Evaristo Carrillo; Carlos Leyva; Rafael Rodríguez-Martinez; José Elizundia; Pedro Antonio Robles-Trillo; Gerardo Arellano-Rodríguez; Francisco Gerardo Véliz; Juan Ramón Luna-Orozco

    2010-01-01

    Para determinar si la aplicación de días largos artificiales durante el invierno y primavera aumenta la producción láctea de las cabras Alpinas del norte de México, un grupo testigo (GT; n=14), fue expuesto a las variaciones naturales del fotoperiodo de la región durante todo el estudio (10 h y 19 m en el solsticio de invierno y 13 h con 41 m durante el solsticio de verano), mientras otro grupo experimental (GE; n=15), se sujetó a un tratamiento de días largos constantes (16 h de luz/...

  6. Experimental challenge and pathology of highly pathogenic avian influenza virus H5N1 in dunlin (Calidris alpina), an intercontinental migrant shorebird species

    Science.gov (United States)

    Hall, Jeffrey S.; Franson, J. Christian; Gill, Robert E.; Meteyer, Carol U.; TeSlaa, Joshua L.; Nashold, Sean W.; Dusek, Robert J.; Ip, Hon S.

    2011-01-01

    Background Shorebirds (Charadriiformes) are considered one of the primary reservoirs of avian influenza. Because these species are highly migratory, there is concern that infected shorebirds may be a mechanism by which highly pathogenic avian influenza virus (HPAIV) H5N1 could be introduced into North America from Asia. Large numbers of dunlin (Calidris alpina) migrate from wintering areas in central and eastern Asia, where HPAIV H5N1 is endemic, across the Bering Sea to breeding areas in Alaska. Low pathogenic avian influenza virus has been previously detected in dunlin, and thus, dunlin represent a potential risk to transport HPAIV to North America. To date no experimental challenge studies have been performed in shorebirds.

  7. Risk management and measuring productivity with POAS--Point of Act System--a medical information system as ERP (Enterprise Resource Planning) for hospital management.

    Science.gov (United States)

    Akiyama, M

    2007-01-01

    The concept of our system is not only to manage material flows, but also to provide an integrated management resource, a means of correcting errors in medical treatment, and applications to EBM (evidence-based medicine) through the data mining of medical records. Prior to the development of this system, electronic processing systems in hospitals did a poor job of accurately grasping medical practice and medical material flows. With POAS (Point of Act System), hospital managers can solve the so-called, "man, money, material, and information" issues inherent in the costs of healthcare. The POAS system synchronizes with each department system, from finance and accounting, to pharmacy, to imaging, and allows information exchange. We can manage Man (Business Process), Material (Medical Materials and Medicine), Money (Expenditure for purchase and Receipt), and Information (Medical Records) completely by this system. Our analysis has shown that this system has a remarkable investment effect - saving over four million dollars per year - through cost savings in logistics and business process efficiencies. In addition, the quality of care has been improved dramatically while error rates have been reduced - nearly to zero in some cases.

  8. Abundance of microbes involved in nitrogen transformation in the rhizosphere of Leucanthemopsis alpina (L.) Heywood grown in soils from different sites of the Damma glacier forefield.

    Science.gov (United States)

    Töwe, Stefanie; Albert, Andreas; Kleineidam, Kristina; Brankatschk, Robert; Dümig, Alexander; Welzl, Gerhard; Munch, Jean Charles; Zeyer, Josef; Schloter, Michael

    2010-11-01

    Glacier forefields are an ideal playground to investigate the role of development stages of soils on the formation of plant-microbe interactions as within the last decades, many alpine glaciers retreated, whereby releasing and exposing parent material for soil development. Especially the status of macronutrients like nitrogen differs between soils of different development stages in these environments and may influence plant growth significantly. Thus, in this study, we reconstructed major parts of the nitrogen cycle in the rhizosphere soil/root system of Leucanthemopsis alpina (L.) HEYWOOD: as well as the corresponding bulk soil by quantifying functional genes of nitrogen fixation (nifH), nitrogen mineralisation (chiA, aprA), nitrification (amoA AOB, amoA AOA) and denitrification (nirS, nirK and nosZ) in a 10-year and a 120-year ice-free soil of the Damma glacier forefield. We linked the results to the ammonium and nitrate concentrations of the soils as well as to the nitrogen and carbon status of the plants. The experiment was performed in a greenhouse simulating the climatic conditions of the glacier forefield. Samples were taken after 7 and 13 weeks of plant growth. Highest nifH gene abundance in connection with lowest nitrogen content of L. alpina was observed in the 10-year soil after 7 weeks of plant growth, demonstrating the important role of associative nitrogen fixation for plant development in this soil. In contrast, in the 120-year soil copy numbers of genes involved in denitrification, mainly nosZ were increased after 13 weeks of plant growth, indicating an overall increased microbial activity status as well as higher concentrations of nitrate in this soil.

  9. Hydrological Features on Subalpine Forest Zone in the East of Qinghai-Tibet Plateau

    Science.gov (United States)

    Zhong, X.; Cheng, G.; Guo, W.

    2008-12-01

    The Hengduan mountain chains of China is situated on the east of Qinghai-Tibet Plateau with area of more than 400,000 km2. Mountains and rivers run through in north-south direction, and are collocated side by side on east-west. Elevation difference between ridges and valleys has great disparity, normally of 1000-2500m, so the vertical zones of vegetation are very distinct. Subalpine coniferous forest zone, mainly composed of fir (Abies) and spruce (Picea), is on altitude of 2800-4200m, which is a chief component of the forested area in southwest China, and an important region for water conservation of several international rivers inlcuding Nujiang River and Lancangjiang River, as well as the world-famous Changjiang River. Thus, it has both theoretical and practical significance to study hydrological process and laws of forest in this region. The study area is located at the Gongga Mountain, on the east edge of the Hengduan mountain chains. Elevation of the main peak is 7556m, and elevation difference between ridge and valley on the eastern slope is 6400m. An ecological observation station was built at altitude of 3000m on the eastern slope of Gongga Mountain in 1988, mainly for alpine ecology and forest hydrology research. Based on the analysis of 20- years observation data from this station, it is revealed that hydrological process of forest in this area has several features as follows: (1) Canopy interception of primitive fir (Abies) forest is obviously greater than other tree species, and interception rate is 30-40%. Maximal canopy interception of one-time precipitation of primitive fir forest is commonly 2-5mm. According to observation data of canopy interception, a conceptual model of canopy interception of fir forest is established: R=1.69[(1-exp(-0.41P))+0.19P (P is precipitation in mm); (2) Natural valid moisture holding capacity in layer of moss-decayed wood and leaves beneath trees is up to 5.6mm. Porosity in soil surface layer and non-capillary porosity

  10. Comparison of remote sensing and plant trait-based modelling to predict ecosystem services in subalpine grasslands

    Czech Academy of Sciences Publication Activity Database

    Homolová, Lucie; Schaepman, M. E.; Lamarque, L.; Clevers, J.G.P.W.; de Bello, Francesco; Thuiller, W.; Lavorel, S.

    2014-01-01

    Roč. 5, č. 8 (2014), č. článku 100. ISSN 2150-8925 Institutional support: RVO:67179843 ; RVO:67985939 Keywords : land-use change * leaf chlorophyll content * imaging spectroscopy * water-content * aviris data * spectral reflectance * hyperspectral data * species richness * area index * vegetation * aisa * biomass * ecosystem properties * ecosystem services * linear regression * remote sensing * spatial heterogeneity * subalpine grasslands Subject RIV: EH - Ecology, Behaviour; EF - Botanics (BU-J) Impact factor: 2.255, year: 2014

  11. The Effect of Re-Planting Trees on Soil Microbial Communities in a Wildfire-Induced Subalpine Grassland

    OpenAIRE

    Ed-Haun Chang; Guanglong Tian; Chih-Yu Chiu

    2017-01-01

    Wildfire often causes tremendous changes in ecosystems, particularly in subalpine and alpine areas, which are vulnerable due to severe climate conditions such as cold temperature and strong wind. This study aimed to clarify the effect of tree re-planting on ecosystem services such as the soil microbial community after several decades. We compared the re-planted forest and grassland with the mature forest as a reference in terms of soil microbial biomass C and N (Cmic and Nmic), enzyme activit...

  12. Effects of long-term population fluctuations of a top predator on invertebrate communities in subalpine ponds in Colorado

    OpenAIRE

    Wissinger, S.; Whiteman, H.; Denoël, Mathieu; Greig, H.; Butkas, K.

    2006-01-01

    Experimental and comparative data from subalpine ponds with and without tiger salamanders (Ambystoma tigrinum nebulosum) suggest that this species is a keystone predator on benthic and planktonic prey communities. At our study site in central Colorado, the population size of salamanders has fluctuated cyclically over the past 20 years from fewer than 100 to over 5000 individuals. Here we present long-term benthic data that reveal taxon- and habitat-specific correlations with fluctuations in s...

  13. Climate Risk Modelling of Balsam Woolly Adelgid Damage Severity in Subalpine Fir Stands of Western North America.

    Science.gov (United States)

    Hrinkevich, Kathryn H; Progar, Robert A; Shaw, David C

    2016-01-01

    The balsam woolly adelgid (Adelges piceae (Ratzeburg) (Homoptera: Adelgidae)) (BWA) is a nonnative, invasive insect that threatens Abies species throughout North America. It is well established in the Pacific Northwest, but continues to move eastward through Idaho and into Montana and potentially threatens subalpine fir to the south in the central and southern Rocky Mountains. We developed a climatic risk model and map that predicts BWA impacts to subalpine fir using a two-step process. Using 30-year monthly climate normals from sites with quantitatively derived BWA damage severity index values, we built a regression model that significantly explained insect damage. The sites were grouped into two distinct damage categories (high damage and mortality versus little or no mortality and low damage) and the model estimates for each group were used to designate distinct value ranges for four climatic risk categories: minimal, low, moderate, and high. We then calculated model estimates for each cell of a 4-kilometer resolution climate raster and mapped the risk categories over the entire range of subalpine fir in the western United States. The spatial variation of risk classes indicates a gradient of climatic susceptibility generally decreasing from the Olympic Peninsula in Washington and the Cascade Range in Oregon and Washington moving eastward, with the exception of some high risk areas in northern Idaho and western Montana. There is also a pattern of decreasing climatic susceptibility from north to south in the Rocky Mountains. Our study provides an initial step for modeling the relationship between climate and BWA damage severity across the range of subalpine fir. We showed that September minimum temperature and a metric calculated as the maximum May temperature divided by total May precipitation were the best climatic predictors of BWA severity. Although winter cold temperatures and summer heat have been shown to influence BWA impacts in other locations, these

  14. The Response of Subalpine Vegetation to Climate Change and Bark Beetle Infestations: A Multi-Scale Interaction.

    Science.gov (United States)

    Foster, A.; Shuman, J. K.; Shugart, H. H., Jr.; Negrón, J. F.

    2015-12-01

    Mean annual temperatures in the western United States have increased in the last few decades, and are predicted to continue warming. In the subalpine zone of the Rocky Mountains, this warming is also predicted to increase the frequency and severity of spruce beetle outbreaks. Climate change itself may affect this vegetation, potentially leading to shifts in species compositions. These forests are a crucial part of the US's carbon budget, thus it is important to analyze how climate change and bark beetles in conjunction will affect the biomass and species composition of vegetation in subalpine zone. UVAFME is an individual-based gap model that simulates biomass and species composition of a forest. This model has been quantitatively tested at various Rocky Mountain sites in the Front Range, and has been shown to accurately simulate the vegetation dynamics in the region. UVAFME has been updated with a spruce beetle subroutine that calculates the probability for beetle infestation of each tree on a plot. This probability is based on site, climate, and individual tree characteristics, such as temperature; stand structure; and tree stress level, size, and age. These governing characteristics are based on data from the US Forest Service, and other studies on spruce susceptibility and spruce beetle phenology. UVAFME is then run with multiple climate change and beetle scenarios to determine the net effect of both variables on subalpine vegetation. These results are compared among the different scenarios and to current forest inventory data. We project that increasing temperatures due to climate change will cause an increase in the frequency and severity of spruce beetle outbreaks, leading to a decrease in the biomass and dominance of Engelmann spruce. These results are an important step in understanding the possible futures for the vegetation of subalpine zone in the Rocky Mountains.

  15. Climate Risk Modelling of Balsam Woolly Adelgid Damage Severity in Subalpine Fir Stands of Western North America.

    Directory of Open Access Journals (Sweden)

    Kathryn H Hrinkevich

    Full Text Available The balsam woolly adelgid (Adelges piceae (Ratzeburg (Homoptera: Adelgidae (BWA is a nonnative, invasive insect that threatens Abies species throughout North America. It is well established in the Pacific Northwest, but continues to move eastward through Idaho and into Montana and potentially threatens subalpine fir to the south in the central and southern Rocky Mountains. We developed a climatic risk model and map that predicts BWA impacts to subalpine fir using a two-step process. Using 30-year monthly climate normals from sites with quantitatively derived BWA damage severity index values, we built a regression model that significantly explained insect damage. The sites were grouped into two distinct damage categories (high damage and mortality versus little or no mortality and low damage and the model estimates for each group were used to designate distinct value ranges for four climatic risk categories: minimal, low, moderate, and high. We then calculated model estimates for each cell of a 4-kilometer resolution climate raster and mapped the risk categories over the entire range of subalpine fir in the western United States. The spatial variation of risk classes indicates a gradient of climatic susceptibility generally decreasing from the Olympic Peninsula in Washington and the Cascade Range in Oregon and Washington moving eastward, with the exception of some high risk areas in northern Idaho and western Montana. There is also a pattern of decreasing climatic susceptibility from north to south in the Rocky Mountains. Our study provides an initial step for modeling the relationship between climate and BWA damage severity across the range of subalpine fir. We showed that September minimum temperature and a metric calculated as the maximum May temperature divided by total May precipitation were the best climatic predictors of BWA severity. Although winter cold temperatures and summer heat have been shown to influence BWA impacts in other

  16. The Effect of Re-Planting Trees on Soil Microbial Communities in a Wildfire-Induced Subalpine Grassland

    Directory of Open Access Journals (Sweden)

    Ed-Haun Chang

    2017-10-01

    Full Text Available Wildfire often causes tremendous changes in ecosystems, particularly in subalpine and alpine areas, which are vulnerable due to severe climate conditions such as cold temperature and strong wind. This study aimed to clarify the effect of tree re-planting on ecosystem services such as the soil microbial community after several decades. We compared the re-planted forest and grassland with the mature forest as a reference in terms of soil microbial biomass C and N (Cmic and Nmic, enzyme activities, phospholipid fatty acids (PLFA composition, and denaturing gradient gel electrophoresis (DGGE. The Cmic and Nmic did not differ among the grassland, re-planted forest and mature forest soil; however, ratios of Cmic/Corg and Nmic/Ntot decreased from the grassland to re-planted forest and mature forest soil. The total PLFAs and those attributed to bacteria and Gram-positive and Gram-negative bacteria did not differ between the re-planted forest and grassland soil. Principle component analysis of the PLFA content separated the grassland from re-planted forest and mature forest soil. Similarly, DGGE analysis revealed changes in both bacterial and fungal community structures with changes in vegetation. Our results suggest that the microbial community structure changes with the re-planting of trees after a fire event in this subalpine area. Recovery of the soil microbial community to the original state in a fire-damaged site in a subalpine area may require decades, even under a re-planted forest.

  17. Responses Of Subalpine Conifer Seedling Germination And Survival To Soil Microclimate In The Alpine Treeline Warming Experiment

    Science.gov (United States)

    Castanha, C.; Moyes, A. B.; Torn, M. S.; Germino, M. J.; Kueppers, L. M.

    2011-12-01

    At Niwot Ridge, Colorado, we used common gardens and climate manipulations to investigate potential subalpine tree species range shifts due to climate change. In Fall 2009 we harvested seed from local populations of limber pine and Englemann spruce, which we sowed in 3 experimental sites spanning an elevation gradient from lower subalpine forest (3080m asl), to the upper subalpine treeline ecotone (3400m asl), to the alpine tundra (3550m asl). In October we turned on overhead infrared heaters designed to increase growing season surface soil temperature by 4-5°C, and following snowmelt in 2010 we crossed this heating treatment with manual watering, adding 3mm of water each week. Here we report on the species, site, and treatment effects on seedling emergence and survival as mediated by snowmelt date, soil temperature, and soil moisture. Depending on the site and plot, heating accelerated germination by 1 to 4 weeks. Germination degree days (heat accumulation required for seed germination) were greater for pine than for spruce and greater in drier plots. Seedling survival was explained by date of emergence, with older seedlings more likely to survive the season. Survival was also explained by drought degree days -- the number of days below critical soil moisture thresholds compounded by high temperature -- with lower thresholds for spruce than for pine. Our preliminary results indicate that a warmer environment will stimulate germination for both species, but that, survival - especially for spruce - will be critically modulated by summer soil moisture.

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

    Science.gov (United States)

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

    2009-12-01

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

  19. Modeling the accumulation of As, Cd, Cu, Pb and Zn in grasses (Agrotis sp. and Poa sp. and stinging nettle (Urtica dioica on selected sites taking into account soil physico-chemical properties

    Directory of Open Access Journals (Sweden)

    Boshoff M. C.

    2013-04-01

    Full Text Available The effect of soil properties on the accumulation of metals in two vegetation types was evaluated at 10 sites with a wide variation in soil physicochemical properties pH, organic carbon, clay percentage , total soil metal concentration and exchangeable soil metal content. Accumulation modeling was conducted for grasses (Agrostis sp. and Poa sp. and stinging nettle (Urtica dioica.

  20. Modeling the accumulation of As, Cd, Cu, Pb and Zn in grasses (Agrotis sp. and Poa sp. and stinging nettle (Urtica dioica on selected sites taking into account soil physico-chemical properties

    Directory of Open Access Journals (Sweden)

    Boshoff M.C.

    2014-07-01

    Full Text Available The effect of soil properties on the accumulation of metals in two vegetation types was evaluated at 10 sites with a wide variation in soil physicochemical properties pH, organic carbon, clay percentage , total soil metal concentration and exchangeable soil metal content. Accumulation modeling was conducted for grasses (Agrostis sp. and Poa sp. and stinging nettle (Urtica dioica.

  1. Response of subalpine grasslands communities to clear-cut and prescribed burnt to control shrub encroachment in Pyrenees

    Science.gov (United States)

    Alados, Concepción L.; Gartzia, Maite; Nuche, Paloma; Saiz, Hugo; Pueyo, Yolanda

    2017-04-01

    Anthropogenic activities have modified vegetation in subalpine belts for long time, lowering treeline ecotone and influencing landscape mainly through grazing and fire. During the last decades the abandonment of traditional land use practices and global warming are contributing largely to the colonization of woody species in subalpine grasslands causing irreversible changes in ecosystem functioning. To prevent those changes a variety of management strategies are carried out to stop the expansion of the highly encroaching shrubs, which require the use of fire and/or clear-cutting, particularly for the conservation of grasslands in subhumid high productive ecosystems. However, it is still poorly understood how different management strategies affect the recovery of subalpine grasslands. Using a field experiment we tested the impact of management treatments on soil properties and vegetation characteristics, including species richness, community structure, interspecies interaction, and complexity of network association. Vegetation was monitored during four years in eight stands (two stands per treatment) where the vegetation was removed by prescribed fire (Burnt treatment), or by mechanical removal (Clear-cut treatment). Two undisturbed E. horridum stands were used as a control (C-Erizón) and two grassland communities regularly grazed (C-Grass) were used as a control for subalpine grassland. Soils nutrients declined in Burnt treatment 3 years after fire, but not differences between Clear-cut and C-Erizón were observed. Species richness and diversity were larger in C-Grass and lower in C-Erizón. Burnt and Clear-cut treatments increased species diversity and richness gradually after 4 year treatment. The proportion of legume forbs, grasses and non-legume forbs did not reach the levels of C-Grass after 4 years of Clear-cut or Burnt treatments. Shrubs and sub-shrubs increased faster after 4 years of burning than after 4 years of clearing, although they did not reach the

  2. Assessing the Climate Sensitivity of Cold Content and Snowmelt in Seasonal Alpine and Subalpine Snowpacks

    Science.gov (United States)

    Jennings, K. S.; Molotch, N. P.

    2016-12-01

    In cold, high-elevation sites, snowpack cold content acts as a buffer against climate warming by resisting snowmelt during periods of positive energy fluxes. To test the climate sensitivity of cold content and snowmelt, we employed the physical SNOWPACK snow model, forced with a 23-year, hourly, quality-controlled, gap-filled meteorological dataset from the Niwot Ridge Long Term Ecological Research (LTER) site in the Front Range mountains of Colorado. SNOWPACK was run at two points with seasonal snowpacks within the LTER, one in the alpine (3528 m) and one in the subalpine (3022 m). Model output was validated using snow water equivalent (SWE), snowpack temperature, and cold content data from snow pits dug near the met stations and automated SWE data from nearby SNOTEL snow pillows. Cold content accumulates primarily through additions of new snow, while negative energy fluxes—cooling through longwave emission and sublimation—play a lesser role, particularly in the deeper snowpack of the alpine. On average, the snowpack energy balance becomes positive on April 1 in the alpine and March 8 in the subalpine. Peak SWE occurs after these dates and its timing is primarily determined by the amount of precipitation received after peak cold content, with persistent snowfall delaying the main snowmelt pulse. Years with lower cold content, due to reduced precipitation and/or increased air temperature, experience an earlier positive energy balance with more melt events occurring before the date of peak SWE, which has implications for soil moisture, streamflow volume and timing, water uptake by vegetation, and microbial respiration. Synthetic warming experiments show significant cold content reductions and increased late-winter/early-spring melt as positive energy balances occur earlier in the snow season (a forward shift between 5.1 and 21.0 days per °C of warming). These results indicate cold, high-elevation sites, which are critical for water resources in the western

  3. [Dynamics of species diversity in artificial restoration process of subalpine coniferous forest].

    Science.gov (United States)

    Wu, Yan; Liu, Qing; He, Hai; Lin, Bo

    2004-08-01

    Through plot investigation and by adopting the concept of space as a substitute for time, the developments of species diversity of trees, shrubs and herbaceous plants in subalpine coniferous plantations at different restoration stages were studied, and the correlation coefficients of species in each layer were discussed. The results indicated that in the restoration process, the species richness, diversity and evenness in subalpine coniferous plantations were gradually increased in a fluctuating way. The restoration process of Picea asperata plantations showed a tendency of development that in favor of resuming species diversity. The indices of species richness (species number and Margalef index) and species diversity (Shannon-Wiener index and Simpson index) of trees increased rapidly from the early stages of plantation establishment to the stage of canopy closing (about 30 yr of stand age) and then presented a tendency of decrease with some slight fluctuations, while the index of species evenness showed a periodical rising trend. For the shrub layer, the indices of species richness (Simpson index and Macintosh index) gradually increased with increasing restoration years, whereas the indices of species diversity (Shannon-Wiener index) decreased in the early stages, sharply increased during the stages of canopy closing, and then slowly decreased, which exhibited a tendency of high-->low-->high. In the layer of herbaceous plants, the indices of species richness (Margalef index and number of species) and species diversity (Simpson index, Macintosh index and Shannon-Wiener index) presented a trend of decrease in the early stages of plantations establishment to canopy closing and increased later on. During this process, herbaceous species and their life forms changed greatly, with shade tolerant species gradually substituting the intolerant species. Among the plantations of different stand ages, the average correlation coefficients of trees, shrubs and herbaceous

  4. Multi-scale patterns of subalpine fir mortality are driven by complex interactions among broad-scale climate, local topography, stand structure, and tree characteristics

    Science.gov (United States)

    Harvey, B. J.; Andrus, R. A.; Orrego, A.; Battaglia, M.; Negrón, J. F.; Veblen, T. T.

    2016-12-01

    Recent tree mortality events across much of western North America have been associated with warming temperatures and elevated drought stress, which can interact with forest stand-structure and tree vigor to drive outbreaks of native insect species. Although cross-scale interactions among drivers of tree-mortality events have been described for some beetle species (e.g., mountain pine beetle or spruce beetle) and their hosts (lodgepole pine and Engelmann spruce), less is known about how drivers at different scales interact to kill subalpine fir (Abies lasiocarpa) in a phenomenon simply dubbed "subalpine fir mortality" or "subalpine fir decline." Understanding the fate of subalpine fir is important, however, because this is commonly the tree species expected to establish and exhibit growth releases following outbreaks of mountain pine beetle or spruce beetle. In this study, we use three decades of field and remote data that span spatial scales from individual trees to sub-continental ecoregions to explore factors associated with subalpine fir mortality and how drivers interact across scales. Between 1991 and 2015, >5 million hectares (ha) of subalpine forest in the US Rocky Mountains have been affected by subalpine fir mortality. At the eco-region scale (1,000s of km), mortality was temporally associated with increases in regional drought stress, suggesting that climate is an important broad-scale driver. However, at the eco-region, landscape, and stand scales (several km to sub ha), mortality was greatest in cooler/wetter topographic locations and in areas with greater pre-mortality subalpine fir dominance. Conversely, mortality was lowest for fir trees in warmer/drier topographic locations and in areas of lesser pre-mortality subalpine fir dominance. This suggests that topographically driven differences in stand structure drive mortality dynamics at meso-scales and moderate the broad-scale influence of climate. Finally, at the tree and tree-neighborhood scale

  5. Caracterização química da carne de cabrito da raça Moxotó e de cruzas Pardo Alpina x Moxotó Chemical characterization of kid meat from Moxotó goat and Pardo Alpina x Moxotó Crossbreeds

    Directory of Open Access Journals (Sweden)

    Frederico José Beserra

    2000-01-01

    Full Text Available O objetivo da pesquisa foi avaliar a composição química da carne de cabrito-mamão (idade média de 72 dias, da raça Moxotó (MOX, grupos genéticos ¾ Pardo Alpina x ¼ Moxotó (3/4 PAMOX e ½ Pardo Alpina x ½ Moxotó (1/2 PAMOX. A análise apresentou valores médios entre 77,80% a 80,25% de umidade; 15,90% a 19,08% de proteína; 1,12% a 1,21% de gordura, e 1,29% a 2,03% de cinzas. Quanto à composição mineral, os valores médios variaram de 5,62 mg/100 g a 8,21 mg/100 g de cálcio; 156,97 mg/100 g a 196,25 mg/100 g de fósforo; 0,26 mg/100 g a 0,48 mg/100 g de ferro; 16,25 mg/100 g a 23,72 mg/100 g de magnésio; 59,20 mg/100 g a 78,79 mg/100 g de sódio, e de 259,69 mg/100 g a 292,24 mg/100 g de potássio. Foram encontradas diferenças significativas a 5% de probabilidade entre os grupos genéticos no que diz respeito à composição de umidade, proteína e cinzas e mineral quanto a elementos estudados. Não houve diferenças entre os valores de gordura dos grupos genéticos.The objective of this study was to evaluate chemical composition of kid meat of Moxotó (MOX, ¾ Pardo Alpina x ¼ Moxotó (3/4 PAMOX and ½ Moxotó x ½ Pardo Alpina (1/2 PAMOX crossbreed goats. Average age of kids at slaughter was 72 days. Kids were fed with cow milk and a protein supplement. Meat analysis showed average values ranging from 77.80% to 80.25% for moisture; from 15.90% to 19.08% for protein; from 1.12% to 1.21% for fat and from 1.29% to 2.03% for ash. For mineral composition, average values ranged from 5.62 mg/100 g to 8.21 mg/100 g for calcium; from 156.97 mg/100 g to 196.25 mg/100 g for phosphorus; from 0.26 mg/100 g to 0.48 mg/100 g for iron; from 16.25 mg/100 g to 23.72 mg/100 g for magnesium; from 59.20 mg/100 g to 78.79 mg/100 g for sodium and from 259.69 mg/100 g to 292.24 mg/100 g for potassium. Genetic groups showed significative differences for composition of moisture, protein and ash values and for mineral composition, in all measured

  6. Limnological research in the deep southern subalpine lakes: synthesis, directions and perspectives

    Directory of Open Access Journals (Sweden)

    Nico Salmaso

    2010-06-01

    Full Text Available Based on a selection of 230 papers published during the last 15 years in international journals, the present work aims at evaluating the state of the art of limnological research in the deep southern subalpine lakes (DSL: Garda, Iseo, Como, Lugano and Maggiore. Historically, most of the limnological research was fostered by the need to find solutions to the problems connected with eutrophication and pollution. Many data are available on the thermal structure, algal nutrient concentrations and phytoplankton of the DSL, while other topics still remain more or less constrained to single lakes. Apart from this geographical bias, a number of aspects emerged from this synoptic view. Limnological research is still linked to the concept of scientific monitoring, while experimental studies and modelling are confined to specific niches; the integration of different disciplines is held back by the division of studies on different compartments; integration of studies and synoptic analyses at a macro regional scale have been carried out only for specific research areas. The DSL are increasingly threatened by new pressures (climatic change, excessive proliferation of toxic cyanobacteria, introduction of new species and new micropollutants and by the interactions among these new and old stressors. In this rapidly changing situation, the paper emphasises the need to define criteria to be used to distinguish research able to produce relevant results and predictive models, which are essential elements for an efficient management of water resources.

  7. Patch-Scale Effects of Equine Disturbance on Arthropod Assemblages and Vegetation Structure in Subalpine Wetlands

    Science.gov (United States)

    Holmquist, Jeffrey G.; Schmidt-Gengenbach, Jutta; Ballenger, Elizabeth A.

    2014-06-01

    Assessments of vertebrate disturbance to plant and animal assemblages often contrast grazed versus ungrazed meadows or other larger areas of usage, and this approach can be powerful. Random sampling of such habitats carries the potential, however, for smaller, more intensely affected patches to be missed and for other responses that are only revealed at smaller scales to also escape detection. We instead sampled arthropod assemblages and vegetation structure at the patch scale (400-900 m2 patches) within subalpine wet meadows of Yosemite National Park (USA), with the goal of determining if there were fine-scale differences in magnitude and directionality of response at three levels of grazing intensity. Effects were both stronger and more nuanced than effects evidenced by previous random sampling of paired grazed and ungrazed meadows: (a) greater negative effects on vegetation structure and fauna in heavily used patches, but (b) some positive effects on fauna in lightly grazed patches, suggested by trends for mean richness and total and population abundances. Although assessment of disturbance at either patch or landscape scales should be appropriate, depending on the management question at hand, our patch-scale work demonstrated that there can be strong local effects on the ecology of these wetlands that may not be detected by comparing larger scale habitats.

  8. A molecular investigation of soil organic carbon composition across a subalpine catchment

    Science.gov (United States)

    Hsu, Hsiao-Tieh; Lawrence, Corey R.; Winnick, Matthew J.; Bargar, John R.; Maher, Katharine

    2018-01-01

    The dynamics of soil organic carbon (SOC) storage and turnover are a critical component of the global carbon cycle. Mechanistic models seeking to represent these complex dynamics require detailed SOC compositions, which are currently difficult to characterize quantitatively. Here, we address this challenge by using a novel approach that combines Fourier transform infrared spectroscopy (FT-IR) and bulk carbon X-ray absorption spectroscopy (XAS) to determine the abundance of SOC functional groups, using elemental analysis (EA) to constrain the total amount of SOC. We used this SOC functional group abundance (SOC-fga) method to compare variability in SOC compositions as a function of depth across a subalpine watershed (East River, Colorado, USA) and found a large degree of variability in SOC functional group abundances between sites at different elevations. Soils at a lower elevation are predominantly composed of polysaccharides, while soils at a higher elevation have more substantial portions of carbonyl, phenolic, or aromatic carbon. We discuss the potential drivers of differences in SOC composition between these sites, including vegetation inputs, internal processing and losses, and elevation-driven environmental factors. Although numerical models would facilitate the understanding and evaluation of the observed SOC distributions, quantitative and meaningful measurements of SOC molecular compositions are required to guide such models. Comparison among commonly used characterization techniques on shared reference materials is a critical next step for advancing our understanding of the complex processes controlling SOC compositions.

  9. Phytoplankton association patterns in the deep southern subalpine lakes (Part 2

    Directory of Open Access Journals (Sweden)

    Nico Salmaso

    2003-08-01

    Full Text Available The three following papers constitute the second, and final, part of a series of papers dedicated to the phytoplankton of the deep subalpine Italian lakes (DSL. The first part, comprising an introduction and three papers on lakes Garda, Como and Maggiore respectively, was published in the volume 61 (1 of this journal (J. Limnol., 61. The research, carried out for three years (two years in L.Como in the period 1997-2000, was a concerted effort by investigators of five Insitutes in Italy and Switzerland. It was generated by the awareness that, despite the large number of papers existing on the phytoplankton of the single DSL, those of a comprehensive nature are very few, and by the perceived interest of a comparative investigation on the phytoplankton of the large lakes in the Insubrian district in the light of the recent progress on the ecology of the freshwater algae. So, in the final paper following those on lakes Iseo and Lugano an effort is made to compare and characterize the different species assemblages in the background of geographical and morphological characteristics, and of recent changes in trophic gradients. Despite often important differences in these respects, and observed various community responses, a common pool of species seems to be identifiable in the district.

  10. Development of partial rock veneers by root throw in a subalpine setting

    Science.gov (United States)

    Osterkamp, W.R.; Toy, T.J.; Lenart, M.T.

    2006-01-01

    Rock veneers stabilize hillslope surfaces, occur especially in areas of immature soil, and form through a variety of process sets that includes root throw. Near Westcliffe, Colorado, USA, data were collected from a 20 ?? 500 m transect on the east slope of the Sangre de Cristo Mountains. Ages of pit/mound complexes with rock fragments exposed at the surface by root throw ranged from recent (freshly toppled tree) to unknown (complete tree decay). Calculations based on dimensions of the pit/mound complexes, estimated time of free topppling, sizes of exposed rock fragments, and percentage rock covers at pit/mound complexes, as well as within the transect area, indicate that recent rates of root throw have resulted in only partial rock veneering since late Pleistocene deglaciation. Weathering of rock fragments prevent development of an extensive rock veneer and causes a balance, achieved within an estimated 700 years, between the rates of rock-fragment exposure by root throw and clast disintegration by chemical reduction. The estimated rate of rock-fragment reduction accounts for part of the fluvial sediment yields observed for forested subalpine areas of western North America. Copyright ?? 2005 John Wiley & Sons, Ltd.

  11. Invasion of subalpine meadows by lodgepole pine in Yellowstone National Park, Wyoming, USA

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    Jakubos, B.; Romme, W.H. (Fort Lewis College, Durango, CO (United States))

    1993-11-01

    Many of the dry and mesic subalpine meadows in Yellowstone National Park are bordered by bands of small lodgepole pine trees. The authors asked whether these stands of small trees represent a directional process of meadow invasion, or alternatively, (1) small patches of postfire succession or; (2) more-or-less stable populations of trees having small stature because of adverse site conditions. Transect studies revealed that the bands of small trees were consistently younger than adjacent forest stands of obvious fire origin, that they lacked any evidence of fire, and that the trees were progressively younger as they approached the meadow. Soils under the young trees generally were more similar to meadow soils than to coniferous forest soils. The authors concluded, therefore, that meadow invasion has been occurring as a directional process since at least the mid- to late 1800s. Frequency of tree establishment in two dry meadows was positively correlated with mean June temperature and total summer precipitation (R[sup 2] = 0.49, P<0.0001, multiple stepwise regression). Thus, the major cause of tree invasion into dry meadows appears to be a regional climatic trend towards warmer and wetter growing seasons since the end of the Little Ice Age. Tree establishment in two mesic meadows was more weakly and inconsistently correlated with weather variables. Thus, the mechanism of invasion of mesic meadows may involve interactions of episodic seed crops and microhabitat changes at the forest border, as well as regional climatic variability. 30 refs., 7 figs., 1 tab.

  12. Targeted grazing for the restoration of sub-alpine shrub-encroached grasslands

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    Massimiliano Probo

    2016-12-01

    Full Text Available The decline of agro-pastoral activities has led to a widespread tree and shrub-encroachment of former semi-natural meso-eutrophic grasslands in many European mountain regions. Temporary night camp areas (TNCA and mineral mix supplements for targeted cattle were arranged over shrub-encroached areas to restore grassland vegetation within the Val Troncea Natural Park (Italy. From 2011 to 2015, their effects on vegetation structure and pastoral value of forage were assessed along permanent transects. Four years after treatments, both practices were effective in reducing the shrub cover and increasing the cover and average height of the herbaceous layer, but changes were more remarkable within TNCA. Moreover, the arrangement of TNCA decreased the cover of nanophanerophytes and increased the cover of graminoids and high quality species, as well as the overall forage pastoral value. In conclusion, TNCA were the most effective pastoral practice to contrast shrub-encroachment and increase herbage mass and forage quality of sub-alpine grasslands.

  13. Extensive wildfires, climate change, and an abrupt state change in subalpine ribbon forests, Colorado.

    Science.gov (United States)

    Calder, W John; Shuman, Bryan

    2017-10-01

    Ecosystems may shift abruptly when the effects of climate change and disturbance interact, and landscapes with regularly patterned vegetation may be especially vulnerable to abrupt shifts. Here we use a fossil pollen record from a regularly patterned ribbon forest (alternating bands of forests and meadows) in Colorado to examine whether past changes in wildfire and climate produced abrupt vegetation shifts. Comparing the percentages of conifer pollen with sedimentary δ18 O data (interpreted as an indicator of temperature or snow accumulation) indicates a first-order linear relationship between vegetation composition and climate change with no detectable lags over the past 2,500 yr (r = 0.55, P changed abruptly within a century of extensive wildfires, which were recognized in a previous study to have burned approximately 80% of the surrounding 1,000 km2 landscape 1,000 yr ago when temperatures rose ~0.5°C. The vegetation change was larger than expected from the effects of climate change alone. Pollen assemblages changed from a composition associated with closed subalpine forests to one similar to modern ribbon forests. Fossil pollen assemblages then remained like those from modern ribbon forests for the following ~1,000 yr, providing a clear example of how extensive disturbances can trigger persistent new vegetation states and alter how vegetation responds to climate. © 2017 by the Ecological Society of America.

  14. Litter Production, Decomposition, and Nutrient Release in Subalpine Forest Communities of the Northwest Himalaya

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    Vinod K. Bisht

    2014-01-01

    Full Text Available Production, decomposition, and release of nutrients from leaf and nonleaf litter were investigated in four subalpine forests of North-West Himalaya, India. Total annual litter fall in four communities varied from 2950.00 to 4040.00 kg ha−1 and was found significant (CD0.05 = 118.2. Decomposition of leaf litter varied from 1.82–3.5% during autumn-winter to 36.14–45.51 during summer rainy season in all stands and percent of mass loss was significantly varied in stands (CD6.00. Similarly, decomposition in nonleaf litter was varied from 0.3–1.1% during autumn-winter to 19.59–30.05% during summer rainy season and was significantly varied irrespective of seasons. However, percent decomposition of leaf litter and the values of decay constant (k were at par in all stands. Total standing state of nutrients in fresh litter as well as release of total nitrogen (N, phosphorus (P, and potassium (K in due course of decomposition (12 months was also varying significantly. The rate of nonleaf litter decomposition was significantly positively correlated with air temperature (r=0.63–0.74 in all communities. The significant correlation (r=0.85 was observed only in Rhododendron-Sorbus forest community (PRS. Study indicates that the air temperature is a major determinant for nonleaf litter decomposition in this region.

  15. Does the aboveground herbivore assemblage influence soil bacterial community composition and richness in subalpine grasslands?

    Science.gov (United States)

    Hodel, Melanie; Schütz, Martin; Vandegehuchte, Martijn L; Frey, Beat; Albrecht, Matthias; Busse, Matt D; Risch, Anita C

    2014-10-01

    Grassland ecosystems support large communities of aboveground herbivores that are known to directly and indirectly affect belowground properties such as the microbial community composition, richness, or biomass. Even though multiple species of functionally different herbivores coexist in grassland ecosystems, most studies have only considered the impact of a single group, i.e., large ungulates (mostly domestic livestock) on microbial communities. Thus, we investigated how the exclusion of four groups of functionally different herbivores affects bacterial community composition, richness, and biomass in two vegetation types with different grazing histories. We progressively excluded large, medium, and small mammals as well as invertebrate herbivores using exclosures at 18 subalpine grassland sites (9 per vegetation type). We assessed the bacterial community composition using terminal restriction fragment length polymorphism (T-RFLP) at each site and exclosure type during three consecutive growing seasons (2009-2011) for rhizosphere and mineral soil separately. In addition, we determined microbial biomass carbon (MBC), root biomass, plant carbon:nitrogen ratio, soil temperature, and soil moisture. Even though several of these variables were affected by herbivore exclusion and vegetation type, against our expectations, bacterial community composition, richness, or MBC were not. Yet, bacterial communities strongly differed between the three growing seasons as well as to some extent between our study sites. Thus, our study indicates that the spatiotemporal variability in soil microclimate has much stronger effects on the soil bacterial communities than the grazing regime or the composition of the vegetation in this high-elevation ecosystem.

  16. Do insects lose flight before they lose their wings? Population genetic structure in subalpine stoneflies.

    Science.gov (United States)

    McCulloch, Graham A; Wallis, Graham P; Waters, Jonathan M

    2009-10-01

    Wing reduction and flightlessness are common features of alpine and subalpine insects, and are typically interpreted as evolutionary adaptations to increase fecundity and promote local recruitment. Here, we assess the impact of wing reduction on dispersal in stoneflies (Plecoptera: Gripopterygidae: Zelandoperla) in southern New Zealand. Specifically, we present comparative phylogeographic analyses (COI; H3) of strong-flying Zelandoperla decorata (144 individuals, 63 localities) vs. the co-distributed but weak-flying Zelandoperla fenestrata species group (186 individuals, 81 localities). The latter group exhibits a variety of morphotypes, ranging from fully winged to completely wingless. Consistent with its capacity for strong flight-mediated dispersal, Z. decorata exhibited no substantial phylogeographic differentiation across its broad South Island range. Conversely the weak-flying fenestrata species group exhibited substantial genetic structure across both fine and broad geographic scales. Intriguingly, the variable degrees of wing development observed within the fenestrata species group had no apparent impact on levels of phylogeographic structure, which were high regardless of morphotype, suggesting that even fully winged specimens of this group do not fly. This finding implies that Zelandoperla flight loss occurs independently of wing loss, and might reflect underlying flight muscle reduction.

  17. Efficient production of arachidonic acid by Mortierella alpina through integrating fed-batch culture with a two-stage pH control strategy.

    Science.gov (United States)

    Li, Xiangyu; Lin, Ye; Chang, Ming; Jin, Qingzhe; Wang, Xingguo

    2015-04-01

    Arachidonic acid (ARA) yield and productivity of Mortierella alpina mutant D20 were enhanced by integrating a fed-batch culture combined with a two-stage pH control strategy. Following a kinetic analysis of the whole fermentation process, a two-stage pH control strategy was developed in which the pH was maintained at 5.5 for the first 48 h and then shifted to 6.5 till the end of fermentation. Using this strategy, a maximum ARA production of 8.12 g/L was achieved. On the basis of pH control, the effects of fed-batch cultures on ARA productivity were further investigated. A maximum ARA productivity of 1.40 g/L/d was obtained with a two-stage constant-speed glucose feeding strategy, starting with a glucose concentration of 50 g/L. This strategy was simple and economical to operate, and it may be possible to apply this approach for large-scale industrial production of ARA. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Coverage of Acta Dermatovenerologica Alpina, Pannonica et Adriatica in Elsevier's CiteScore index: a new tool for measuring the citation impact of academic journals.

    Science.gov (United States)

    Poljak, Mario

    2017-03-01

    In December 2016, Elsevier launched a new tool that helps measure the citation impact of academic journals, called the CiteScore index. The CiteScore index values for 2015 confirmed the status of Acta Dermatovenerologica Alpina, Pannonica et Adriatica (Acta Dermatovenerol APA) as the leading journal in dermatology and sexually transmitted infections in the region. Sixty-five articles published in Acta Dermatovenerol APA from 2012 to 2014 received a total of 77 citations in 2015, resulting in a CiteScore index value of 1.18 for the journal. More than half of the articles published from 2012 to 2014 received at least one citation in 2015. Acta Dermatovenerol APA performed well in all three categories listed because it is ranked 384th out of 1,549 journals in the category General Medicine (75th percentile), 53rd out of 122 journals in the category Dermatology (56th percentile), and 142nd out of 246 journals in the category Infectious Diseases (42nd percentile).

  19. Long-term reactive nitrogen loading alters soil carbon and microbial community properties in a subalpine forest ecosystem

    Science.gov (United States)

    Boot, Claudia M; Hall, Ed K.; Denef, Karolien; Baron, Jill S.

    2016-01-01

    Elevated nitrogen (N) deposition due to increased fossil fuel combustion and agricultural practices has altered global carbon (C) cycling. Additions of reactive N to N-limited environments are typically accompanied by increases in plant biomass. Soil C dynamics, however, have shown a range of different responses to the addition of reactive N that seem to be ecosystem dependent. We evaluated the effect of N amendments on biogeochemical characteristics and microbial responses of subalpine forest organic soils in order to develop a mechanistic understanding of how soils are affected by N amendments in subalpine ecosystems. We measured a suite of responses across three years (2011–2013) during two seasons (spring and fall). Following 17 years of N amendments, fertilized soils were more acidic (control mean 5.09, fertilized mean 4.68), and had lower %C (control mean 33.7% C, fertilized mean 29.8% C) and microbial biomass C by 22% relative to control plots. Shifts in biogeochemical properties in fertilized plots were associated with an altered microbial community driven by reduced arbuscular mycorrhizal (control mean 3.2 mol%, fertilized mean 2.5 mol%) and saprotrophic fungal groups (control mean 17.0 mol%, fertilized mean 15.2 mol%), as well as a decrease in N degrading microbial enzyme activity. Our results suggest that decreases in soil C in subalpine forests were in part driven by increased microbial degradation of soil organic matter and reduced inputs to soil organic matter in the form of microbial biomass.

  20. Trace elements in sub-alpine forest soils on the eastern edge of the Tibetan Plateau, China

    Science.gov (United States)

    Wang, Xiaodan; Cheng, Genwei; Zhong, Xianghao; Li, Mai-He

    2009-08-01

    Industrial development has increased fast in China during the last decades. This has led to a range of environmental problems. Deposition of trace elements to forest ecosystems via the atmosphere is one potential problem. In this paper, we report the results from a pilot study where the trace element levels of the sub-alpine forest soils on the eastern edge of the Tibetan Plateau have been measured. Possible relationships between soil properties and trace element concentrations have also been investigated. The obtained concentrations (mg kg-1) were boron (B) 48.06-53.70, molybdenum (Mo) 1.53-2.26, zinc (Zn) 68.18-79.53, copper (Cu) 36.81-42.44, selenium (Se) 0.33-0.49, cadmium (Cd) 0.16-0.29, lead (Pb) 25.80-30.71, chromium (Cr) 96.10-110.08, nickel (Ni) 30.16-45.60, mercury (Hg) 0.05-0.11, and arsenic (As) 3.09-4.17. With a few exceptions, the element concentration can be characterized as low in the investigated sub-alpine forest soils. No clear differences in trace element levels were found between topsoil and subsoil samples, indicating that the atmospheric deposition of trace element has been low. The soil parent material plays a key role to determine trace element levels. Soil properties, including pHw, organic carbon (OC), clay fraction, cation-exchange capacity (CEC), total iron (Fe), and total aluminum (Al) concentrations were related to trace element concentration using correlation analysis. Total Fe and Al showed the strongest relationships with concentrations of most trace elements in the sub-alpine forest soils. PCA analyses indicated that a significant increase in the number of cars with the fast development of local tourism may result in higher Pb concentration in the future.

  1. Assessing heat fluxes and water quality trends in subalpine lakes from EO

    Science.gov (United States)

    Cazzaniga, Ilaria; Giardino, Claudia; Bresciani, Mariano; Elli, Chiara; Valerio, Giulia; Pilotti, Marco

    2017-04-01

    Lakes play a fundamental role in providing ecosystem services such as water supplying, hydrological regulation, climate change mitigation, touristic recreation (Schallenberg et al., 2013). Preserving and improving of quality of lakes waters, which is a function of either both natural and human influences, is therefore an important action to be considered. Remote Sensing techniques are spreading as useful instrument for lakes, by integrating classical in situ limnological measurements to frequent and synoptic monitoring capabilities. Within this study, Earth Observation data are exploited for understanding the temporal changes of water quality parameters over a decade, as well as for measuring the surface energy fluxes in recent years in deep clear lakes in the European subalpine ecoregion. According to Pareth et al. (2016), subalpine lakes are showing a clear response to climate change with an increase of 0.017 °C /year of lake surface temperature, whilst the human activities contribute to produce a large impact (agriculture, recreation, industry, fishing and drinking) on these lakes. The investigation is focused on Lake Iseo, which has shown a significant deterioration of water quality conditions since the seventies, and on Lake Garda, the largest Italian lake where EO data have been widely used for many purposes and applications (Giardino et al., 2014). Available ENVISAT-MERIS (2002-2012) and Landsat-8-OLI (2013-on going) imagery has been exploited to produce chlorophyll-a (chl-a) concentration maps, while Landsat-8-TIRS imagery has been used for estimating lake surface temperatures. MERIS images were processed through a neural network (namely the C2R processor, Doerffer et al., 2007), to correct the atmospheric effects and to retrieve water constituents concentration in optically complex deep waters. With regard to L8's images, some atmospheric correctors (e.g. ACOLITE and 6SV) were tested and validated to indentify, for each of the two lakes, the more accurate

  2. Hydrologic flow path development varies by aspect during spring snowmelt in complex subalpine terrain

    Science.gov (United States)

    Webb, Ryan W.; Fassnacht, Steven R.; Gooseff, Michael N.

    2018-01-01

    In many mountainous regions around the world, snow and soil moisture are key components of the hydrologic cycle. Preferential flow paths of snowmelt water through snow have been known to occur for years with few studies observing the effect on soil moisture. In this study, statistical analysis of the topographical and hydrological controls on the spatiotemporal variability of snow water equivalent (SWE) and soil moisture during snowmelt was undertaken at a subalpine forested setting with north, south, and flat aspects as a seasonally persistent snowpack melts. We investigated if evidence of preferential flow paths in snow can be observed and the effect on soil moisture through measurements of snow water equivalent and near-surface soil moisture, observing how SWE and near-surface soil moisture vary on hillslopes relative to the toes of hillslopes and flat areas. We then compared snowmelt infiltration beyond the near-surface soil between flat and sloping terrain during the entire snowmelt season using soil moisture sensor profiles. This study was conducted during varying snowmelt seasons representing above-normal, relatively normal, and below-normal snow seasons in northern Colorado. Evidence is presented of preferential meltwater flow paths at the snow-soil interface on the north-facing slope causing increases in SWE downslope and less infiltration into the soil at 20 cm depth; less association is observed in the near-surface soil moisture (top 7 cm). We present a conceptualization of the meltwater flow paths that develop based on slope aspect and soil properties. The resulting flow paths are shown to divert at least 4 % of snowmelt laterally, accumulating along the length of the slope, to increase the snow water equivalent by as much as 170 % at the base of a north-facing hillslope. Results from this study show that snow acts as an extension of the vadose zone during spring snowmelt and future hydrologic investigations will benefit from studying the snow and soil

  3. Conifer density within lake catchments predicts fish mercury concentrations in remote subalpine lakes

    Science.gov (United States)

    Eagles-Smith, Collin A.; Herring, Garth; Johnson, Branden L.; Graw, Rick

    2016-01-01

    Remote high-elevation lakes represent unique environments for evaluating the bioaccumulation of atmospherically deposited mercury through freshwater food webs, as well as for evaluating the relative importance of mercury loading versus landscape influences on mercury bioaccumulation. The increase in mercury deposition to these systems over the past century, coupled with their limited exposure to direct anthropogenic disturbance make them useful indicators for estimating how changes in mercury emissions may propagate to changes in Hg bioaccumulation and ecological risk. We evaluated mercury concentrations in resident fish from 28 high-elevation, sub-alpine lakes in the Pacific Northwest region of the United States. Fish total mercury (THg) concentrations ranged from 4 to 438 ng/g wet weight, with a geometric mean concentration (±standard error) of 43 ± 2 ng/g ww. Fish THg concentrations were negatively correlated with relative condition factor, indicating that faster growing fish that are in better condition have lower THg concentrations. Across the 28 study lakes, mean THg concentrations of resident salmonid fishes varied as much as 18-fold among lakes. We used a hierarchal statistical approach to evaluate the relative importance of physiological, limnological, and catchment drivers of fish Hg concentrations. Our top statistical model explained 87% of the variability in fish THg concentrations among lakes with four key landscape and limnological variables: catchment conifer density (basal area of conifers within a lake's catchment), lake surface area, aqueous dissolved sulfate, and dissolved organic carbon. Conifer density within a lake's catchment was the most important variable explaining fish THg concentrations across lakes, with THg concentrations differing by more than 400 percent across the forest density spectrum. These results illustrate the importance of landscape characteristics in controlling mercury bioaccumulation in fish.

  4. Calcium induces long-term legacy effects in a subalpine ecosystem.

    Directory of Open Access Journals (Sweden)

    Urs Schaffner

    Full Text Available Human activities have transformed a significant proportion of the world's land surface, with profound effects on ecosystem processes. Soil applications of macronutrients such as nitrate, phosphorus, potassium or calcium are routinely used in the management of croplands, grasslands and forests to improve plant health or increase productivity. However, while the effects of continuous fertilization and liming on terrestrial ecosystems are well documented, remarkably little is known about the legacy effect of historical fertilization and liming events in terrestrial ecosystems and of the mechanisms involved. Here, we show that more than 70 years after the last application of lime on a subalpine grassland, all major soil and plant calcium pools were still significantly larger in limed than in unlimed plots, and that the resulting shift in the soil calcium/aluminium ratio continues to affect ecosystem services such as primary production. The difference in the calcium content of the vegetation and the topmost 10 cm of the soil in limed vs. unlimed plots amounts to approximately 19.5 g m(-2, equivalent to 16.3% of the amount that was added to the plots some 70 years ago. In contrast, plots that were treated with nitrogen-phosphorus-potassium fertilizer in the 1930s did not differ from unfertilized plots in any of the soil and vegetation characteristics measured. Our findings suggest that the long-term legacy effect of historical liming is due to long-term storage of added calcium in stable soil pools, rather than a general increase in nutrient availability. Our results demonstrate that single applications of calcium in its carbonated form can profoundly and persistently alter ecosystem processes and services in mountain ecosystems.

  5. Net primary productivity of subalpine meadows in Yosemite National Park in relation to climate variability

    Science.gov (United States)

    Moore, Peggy E.; Van Wagtendonk, Jan W.; Yee, Julie L.; McClaran, Mitchel P.; Cole, David N.; McDougald, Neil K.; Brooks, Matthew L.

    2013-01-01

    Subalpine meadows are some of the most ecologically important components of mountain landscapes, and primary productivity is important to the maintenance of meadow functions. Understanding how changes in primary productivity are associated with variability in moisture and temperature will become increasingly important with current and anticipated changes in climate. Our objective was to describe patterns and variability in aboveground live vascular plant biomass in relation to climatic factors. We harvested aboveground biomass at peak growth from four 64-m2 plots each in xeric, mesic, and hydric meadows annually from 1994 to 2000. Data from nearby weather stations provided independent variables of spring snow water content, snow-free date, and thawing degree days for a cumulative index of available energy. We assembled these climatic variables into a set of mixed effects analysis of covariance models to evaluate their relationships with annual aboveground net primary productivity (ANPP), and we used an information theoretic approach to compare the quality of fit among candidate models. ANPP in the xeric meadow was negatively related to snow water content and thawing degree days and in the mesic meadow was negatively related to snow water content. Relationships between ANPP and these 2 covariates in the hydric meadow were not significant. Increasing snow water content may limit ANPP in these meadows if anaerobic conditions delay microbial activity and nutrient availability. Increased thawing degree days may limit ANPP in xeric meadows by prematurely depleting soil moisture. Large within-year variation of ANPP in the hydric meadow limited sensitivity to the climatic variables. These relationships suggest that, under projected warmer and drier conditions, ANPP will increase in mesic meadows but remain unchanged in xeric meadows because declines associated with increased temperatures would offset the increases from decreased snow water content.

  6. Intraguild predation and cannibalism among larvae of detritivorous caddisflies in subalpine wetlands

    Science.gov (United States)

    Wissinger, S.A.; Sparks, G.B.; Rouse, G.L.; Brown, W.S.; Steltzer, Heidi

    1996-01-01

    Comparative data from subalpine wetlands in Colorado indicate that larvae of the limnephilid caddisflies, Asynarchus nigriculus and Limnephilus externus, are reciprocally abundant among habitats - Limnephilus larvae dominate in permanent waters, whereas Asynarchus larvae dominate in temporary basins. The purpose of this paper is to report on field and laboratory experiments that link this pattern of abundance to biotic interactions among larvae. In the first field experiment, growth and survival were compared in single and mixed species treatments in littoral enclosures. Larvae, which eat mainly vascular plant detritus, grew at similar rates among treatments in both temporary and permanent habitats suggesting that exploitative competition is not important under natural food levels and caddisfly densities. However, the survival of Limnephilus larvae was reduced in the presence of Asynarchus larvae. Subsequent behavioral studies in laboratory arenas revealed that Asynarchus larvae are extremely aggressive predators on Limnephilus larvae. In a second field experiment we manipulated the relative sizes of larvae and found that Limnephilus larvae were preyed on only when Asynarchus larvae had the same size advantage observed in natural populations. Our data suggest that the dominance of Asynarchus larvae in temporary habitats is due to asymmetric intraguild predation (IGP) facilitated by a phenological head start in development. These data do not explain the dominance of Limnephilus larvae in permanent basins, which we show elsewhere to be an indirect effect of salamander predation. Behavioral observations also revealed that Asynarchus larvae are cannibalistic. In contrast to the IGP on Limnephilus larvae, Asynarchus cannibalism occurs among same-sized larvae and often involves the mobbing of one victim by several conspecifics. In a third field experiment, we found that Asynarchus cannibalism was not density-dependent and occurred even at low larval densities. We

  7. Declines in low-elevation subalpine tree populations outpace growth in high-elevation populations with warming

    Science.gov (United States)

    Conlisk, Erin; Castanha, Cristina; Germino, Matthew J.; Veblen, Thomas T; Smith, Jeremy M.; Kueppers, Lara M.

    2017-01-01

    Species distribution shifts in response to climate change require that recruitment increase beyond current range boundaries. For trees with long life spans, the importance of climate-sensitive seedling establishment to the pace of range shifts has not been demonstrated quantitatively.Using spatially explicit, stochastic population models combined with data from long-term forest surveys, we explored whether the climate-sensitivity of recruitment observed in climate manipulation experiments was sufficient to alter populations and elevation ranges of two widely distributed, high-elevation North American conifers.Empirically observed, warming-driven declines in recruitment led to rapid modelled population declines at the low-elevation, ‘warm edge’ of subalpine forest and slow emergence of populations beyond the high-elevation, ‘cool edge’. Because population declines in the forest occurred much faster than population emergence in the alpine, we observed range contraction for both species. For Engelmann spruce, this contraction was permanent over the modelled time horizon, even in the presence of increased moisture. For limber pine, lower sensitivity to warming may facilitate persistence at low elevations – especially in the presence of increased moisture – and rapid establishment above tree line, and, ultimately, expansion into the alpine.Synthesis. Assuming 21st century warming and no additional moisture, population dynamics in high-elevation forests led to transient range contractions for limber pine and potentially permanent range contractions for Engelmann spruce. Thus, limitations to seedling recruitment with warming can constrain the pace of subalpine tree range shifts.

  8. Nitrogen deposition but not ozone affects productivity and community composition of subalpine grassland after 3 yr of treatment.

    Science.gov (United States)

    Bassin, Seraina; Volk, Matthias; Suter, Matthias; Buchmann, Nina; Fuhrer, Jürg

    2007-01-01

    A field experiment was established at 2000 m above sea level (asl) in the central Swiss Alps with the aim of investigating the effects of elevated ozone (O(3)) and nitrogen deposition (N), and of their combination, on above-ground productivity and species composition of subalpine grassland. One hundred and eighty monoliths were extracted from a species-rich Geo-Montani-Nardetum pasture and exposed in a free-air O(3)-fumigation system to one of three concentrations of O(3) (ambient, 1.2 x ambient, 1.6 x ambient) and five concentrations of additional N. Above-ground biomass, proportion of functional groups and normalized difference vegetation index (NDVI) were measured annually. After 3 yr of treatment, the vegetation responded to the N input with an increase in above-ground productivity and altered species composition, but without changes resulting from elevated O(3). N input > 10 kg N ha(-1) yr(-1) was sufficient to affect the composition of functional groups, with sedges benefiting over-proportionally. No interaction of O(3) x N was observed, except for NDVI; positive effects of N addition on canopy greenness were counteracted by accelerated leaf senescence in the highest O(3) treatment. The results suggest that effects of elevated O(3) on the productivity and floristic composition of subalpine grassland may develop slowly, regardless of the sensitive response to increasing N.

  9. Effects of tourism and topography on vegetation diversity in the subalpine meadows of the Dongling Mountains of Beijing, China.

    Science.gov (United States)

    Zhang, Jin-Tun; Xiang, ChunLing; Li, Min

    2012-02-01

    Subalpine meadows in the Dongling Mountains (located at E115º26'-115º40', N40º00'-40º05') of Beijing, China are important for tourism and the provision of ecosystem services. However, because of poor management serious degradation has occurred on these subalpine meadows. The aim of this paper is to present a quantitative analysis of effects of tourism disturbance and topography on the status and diversity of montane meadow communities and to provide direction for improved management. Sixty quadrats of 2 × 2 m(2) along 10 transects were set up to collect data on site characteristics and vegetation status. The relationships between community composition and structure, species diversity, and tourism disturbance and topographic variables were analyzed by multivariate methods (TWINSPAN and CCA). The results showed that eight meadow communities were identified by TWINSPAN. Most of them were seriously degraded. The first CCA axis identified an elevation and tourism disturbance intensity gradient, which illustrated that tourism disturbance and elevation were most important factors influencing meadow types, composition and structure. Some resistant species and response species to tourism disturbance were identified and can be used as indicator species of tourism disturbance. Species richness, heterogeneity and evenness were closely related to tourism disturbance and elevation. It is concluded that tourism disturbance must be controlled to enable grassland rehabilitation to occur in the meadows. Measures of effective management of the meadows were discussed.

  10. Effects of Tourism and Topography on Vegetation Diversity in the Subalpine Meadows of the Dongling Mountains of Beijing, China

    Science.gov (United States)

    Zhang, Jin-Tun; Xiang, Chunling; Li, Min

    2012-02-01

    Subalpine meadows in the Dongling Mountains (located at E115º26'-115º40', N40º00'-40º05') of Beijing, China are important for tourism and the provision of ecosystem services. However, because of poor management serious degradation has occurred on these subalpine meadows. The aim of this paper is to present a quantitative analysis of effects of tourism disturbance and topography on the status and diversity of montane meadow communities and to provide direction for improved management. Sixty quadrats of 2 × 2 m2 along 10 transects were set up to collect data on site characteristics and vegetation status. The relationships between community composition and structure, species diversity, and tourism disturbance and topographic variables were analyzed by multivariate methods (TWINSPAN and CCA). The results showed that eight meadow communities were identified by TWINSPAN. Most of them were seriously degraded. The first CCA axis identified an elevation and tourism disturbance intensity gradient, which illustrated that tourism disturbance and elevation were most important factors influencing meadow types, composition and structure. Some resistant species and response species to tourism disturbance were identified and can be used as indicator species of tourism disturbance. Species richness, heterogeneity and evenness were closely related to tourism disturbance and elevation. It is concluded that tourism disturbance must be controlled to enable grassland rehabilitation to occur in the meadows. Measures of effective management of the meadows were discussed.

  11. Subalpine vegetation pattern three decades after stand-replacing fire: Effects of landscape context and topography on plant community composition, tree regeneration, and diversity

    Science.gov (United States)

    Jonathan D. Coop; Robert T. Massatti; Anna W. Schoettle

    2010-01-01

    These subalpine wildfires generated considerable, persistent increases in plant species richness at local and landscape scales, and a diversity of plant communities. The findings suggest that fire suppression in such systems must lead to reduced diversity. Concerns about post-fire invasion by exotic plants appear unwarranted in high-elevation wilderness settings.

  12. Verification of satellite radar remote sensing based estimates of boreal and subalpine growing seasons using an ecosystem process model and surface biophysical measurement network information

    Science.gov (United States)

    McDonald, K. C.; Kimball, J. S.; Zimmerman, R.

    2002-01-01

    We employ daily surface Radar backscatter data from the SeaWinds Ku-band Scatterometer onboard Quikscat to estimate landscape freeze-thaw state and associated length of the seasonal non-frozen period as a surrogate for determining the annual growing season across boreal and subalpine regions of North America for 2000 and 2001.

  13. Carex sempervirens tussocks induce spatial heterogeneity in litter decomposition, but not in soil properties, in a subalpine grassland in the Central Alps

    Science.gov (United States)

    Fei-Hai Yu; Martin Schutz; Deborah S. Page-Dumroese; Bertil O. Krusi; Jakob Schneller; Otto Wildi; Anita C. Risch

    2011-01-01

    Tussocks of graminoids can induce spatial heterogeneity in soil properties in dry areas with discontinuous vegetation cover, but little is known about the situation in areas with continuous vegetation and no study has tested whether tussocks can induce spatial heterogeneity in litter decomposition. In a subalpine grassland in the Central Alps where vegetation cover is...

  14. Deforestation induces shallow landsliding in the montane and subalpine belts of the Urbión Mountains, Iberian Range, Northern Spain

    Science.gov (United States)

    García-Ruiz, José M.; Beguería, Santiago; Arnáez, José; Sanjuán, Yasmina; Lana-Renault, Noemí; Gómez-Villar, Amelia; Álvarez-Martínez, Javier; Coba-Pérez, Paz

    2017-11-01

    In this study the spatial distribution of shallow landslides in the upper montane and subalpine belts of the Urbión Mountains (Iberian Range, northern Spain) was investigated, particularly in relation to the spatial organization of deforestation and land cover. The upper montane and subalpine belts have been deforested several times since the Neolithic Period, to enlarge the area of summer grasslands for feeding transhumant sheep flocks. Consequently, the timberline was lowered by 400-600 m, and increased the occurrence of severe erosion processes, particularly shallow landslides. This study shows that most of the landslide scars are in the summer grasslands area, and that a remarkable extent of the subalpine belt area has been subjected to mass movements. In addition to land use, the soil characteristics and topography help explain the development of conditions most favorable to landsliding. Shallow landslide susceptibility was highest in the upper parts of the slopes near the divides, in areas having slope gradients of 10-30° and deep soils with an increasing proportion of clay with depth. The landslides were clustered and not randomly distributed, and the causes of this spatial distribution are discussed. The current trend of woody encroachment in the upper montane and subalpine belts, resulting from decreasing livestock pressure, will probably reduce the susceptibility of these areas to shallow landslides in the future.

  15. Lab and Field Warming Similarly Advance Germination Date and Limit Germination Rate for High and Low Elevation Provenances of Two Widespread Subalpine Conifers

    Directory of Open Access Journals (Sweden)

    Lara M. Kueppers

    2017-11-01

    Full Text Available Accurately predicting upslope shifts in subalpine tree ranges with warming requires understanding how future forest populations will be affected by climate change, as these are the seed sources for new tree line and alpine populations. Early life history stages are particularly sensitive to climate and are also influenced by genetic variation among populations. We tested the climate sensitivity of germination and initial development for two widely distributed subalpine conifers, using controlled-environment growth chambers with one temperature regime from subalpine forest in the Colorado Rocky Mountains and one 5 °C warmer, and two soil moisture levels. We tracked germination rate and timing, rate of seedling development, and seedling morphology for two seed provenances separated by ~300 m elevation. Warming advanced germination timing and initial seedling development by a total of ~2 weeks, advances comparable to mean differences between provenances. Advances were similar for both provenances and species; however, warming reduced the overall germination rate, as did low soil moisture, only for Picea engelmannii. A three-year field warming and watering experiment planted with the same species and provenances yielded responses qualitatively consistent with the lab trials. Together these experiments indicate that in a warmer, drier climate, P. engelmannii germination, and thus regeneration, could decline, which could lead to declining subalpine forest populations, while Pinus flexilis forest populations could remain robust as a seed source for upslope range shifts.

  16. Distribución natural de Nothofagus alpina y Nothofagus obliqua (nothofagaceae en Argentina, dos especies de primera importancia forestal de los bosques templados norpatagónicos Natural distribution of Nothofagus alpina and Nothofagus obliqua (Nothofagaceae in Argentina, two productively important tree species of the North Patagonian temperate forests

    Directory of Open Access Journals (Sweden)

    Yamila Sabatier

    2011-06-01

    Full Text Available Conocer la distribución natural de cualquier especie es esencial para poder planificar su conservación o uso. El Raulí [Nothofagus alpina (Poepp. & Endl. Oerst. = Nothofagus nervosa (Phil. Dim. et Mil.] y el Roble Pellín [Nothofagus obliqua (Mirb. Oerst. ssp. obliqua] son dos especies forestales de primera importancia en los bosques norpatagónicos, y objetos de un programa de domesticación en curso. En base al cruce de capas de información digital de estudios previos verificada por informantes locales calificados, por controles de campo y por interpretación sobre pantalla de imágenes provistas libremente por Google Earth, se mapeó la distribución natural de ambas especies en Argentina. La presencia del Raulí se registra sobre una superficie de 79.636 ha, mientras que sobre 33.859 ha se desarrollan bosques con presencia de Roble Pellín. La mayor parte de estas superficies se encuentran protegidas por el sistema de Parques Nacionales (97 % del área ocupada con Raulí y 83 % de la ocupada con Roble Pellín, sin embargo varios bosques relevantes para la conservación se hallan bajo jurisdicción de la Provincia de Neuquén, lo cual debería ser considerado al momento de planear una estrategia de conservación para ambas especies.Knowing the natural range of any species is essential to plan its conservation or use. The South-American beeches Raulí [Nothofagus alpina (Poepp. & Endl. Oerst. = Nothofagus nervosa (Phil. Dim. et Mil.] and Roble Pellín [Nothofagus obliqua (Mirb. Oerst. ssp. obliqua] are two important forest tree species of the North Patagonian forests, and the object of a current domestication program. Natural distribution of both beeches in Argentina was mapped based on digital information of previous works which was verified by local qualified informants, ground control check and visual interpretation of images freely provided by Google Earth. Raulí is present over a surface of 79,636 ha, while 33,859 ha are occupied by

  17. Encapsulated Somatic Embryos and Zygotic Embryos for Obtaining Artificial Seeds of Rauli-Beech (Nothofagus alpina (Poepp. & Endl. Oerst. Encapsulado de Embriones Somáticos y Embriones Cigóticos para Obtención de Semillas Artificiales de Raulí (Nothofagus alpina (Poepp. & Endl. Oerst.

    Directory of Open Access Journals (Sweden)

    Priscila Cartes R

    2009-03-01

    Full Text Available Somatic and zygotic embryos from mature seeds of rauli-beech, Nothofagus alpina (Poepp. & Endl. Oerst., were encapsulated in different artificial endosperms in order to generate a cover that fulfills the function of nourishment and protection of the embryos, facilitating their later germination. The content of sodium alginate varied by 4%, 3%, and 2%, as did the immersion time in calcium chloride (CaCl2, which acts as complexing agent. The artificial endosperm components of the Murashige and Skoog medium (MS were added, supplemented with 0.5 mg L-1 indolacetic acid (IAA, 0.5 mg L-1 naphthaleneacetic acid (NAA, 2 mg L-1 6-benzylaminopurine (BAP and 30 g L-1 sucrose. The germinative behaviors of encapsulated somatic and zygotic embryos were evaluated after 4 wk. Comparing the percentages of germination reached by encapsulated somatic and zygotic embryos it was observed that they had similar germinative behavior according to the type of encapsulation applied. However, zygotic embryos substantially exceeded the germination levels reached by somatic embryos, 100% vs. 45% respectively.Embriones somáticos y cigóticos provenientes de semillas maduras de raulí, Nothofagus alpina (Poepp. & Endl. Oerst., se encapsularon en diferentes endospermas sintéticos con el fin de generar una cubierta que cumpla la función de nutrir y proteger al embrión para facilitar su posterior germinación. Se varió el contenido de alginato de sodio al 4%, 3% y 2% y el tiempo de inmersión en cloruro de calcio (CaCl2, el que actúa como agente acomplejante. Además, a la matriz artificial se adicionaron componentes del medio Murashige y Skoog (MS suplementado con: 0,5 mg L-1 de indolacetic acid (IAA, 0,5 mg L-1 de ácido naftalenacético (NAA, 2 mg L-1 de 6-bencilaminopurina (BAP y 30 gL-1 de sacarosa. Al cabo de 4 semanas el porcentaje de germinación de los embriones somáticos y cigóticos encapsulados tuvieron similar comportamiento germinativo según el tipo de

  18. Importance of nitrogen cycling hot spots in an alpine-subalpine ecosystem

    Science.gov (United States)

    Darrouzet-Nardi, A.; Bowman, W. D.

    2009-12-01

    Nitrogen (N) availability in soils is influenced by many microbially catalyzed reactions such as N fixation, denitrification, and N mineralization from soil organic matter (SOM). Reaction rates for these processes are heterogeneous across landscapes, often forming hot spots that have disproportionately high N cycling activity. N cycling hot spots have been documented in many ecosystems at hourly to weekly times scales; however, much less is known about the persistence and importance of N cycling hot spots over longer times scales. Furthermore, few studies have investigated multiple landscape-level measurements of different N cycling processes at the same site. Using a mathematical definition of hot spots, a time series of short-term measurements, ion exchange resins deployed for one year, and nitrogen isotopic signatures in SOM, we investigated the importance of hot spots over longer time scales in a 0.89 km2 alpine-subalpine ecosystem at the Niwot Ridge LTER site. Measurements of KCl-extractable inorganic N taken on multiple measurement dates showed that hot moments of N availabilty occurred in some but not all parts of the study site and at varying times throughout the season. Ion exchange resins deployed for one year showed that N availability hot spots were important though not completely dominant over one year (14% of values accounted for 58% of total resin-extractable inorganic N observed). In contrast, isotopic signatures in 219 SOM samples were well approximated by a normal distribution, suggesting that landscape-level N losses through leaching or gas efflux were more constrained. Denitrification was the possible exception: we saw evidence for several likely hot spots in the wetland areas of our study site. The results of this study suggest that short-term hot spots are important for plant ecological dynamics at our study site and for denitrification, but that long-term N cycling hot spots are less important for other parts of the soil N cycle such as N

  19. Fuel deposition rates of montane and subalpine conifers in the central Sierra Nevada, California, USA

    Science.gov (United States)

    van Wagtendonk, J.W.; Moore, P.E.

    2010-01-01

    Fire managers and researchers need information on fuel deposition rates to estimate future changes in fuel bed characteristics, determine when forests transition to another fire behavior fuel model, estimate future changes in fuel bed characteristics, and parameterize and validate ecosystem process models. This information is lacking for many ecosystems including the Sierra Nevada in California, USA. We investigated fuel deposition rates and stand characteristics of seven montane and four subalpine conifers in the Sierra Nevada. We collected foliage, miscellaneous bark and crown fragments, cones, and woody fuel classes from four replicate plots each in four stem diameter size classes for each species, for a total of 176 sampling sites. We used these data to develop predictive equations for each fuel class and diameter size class of each species based on stem and crown characteristics. There were consistent species and diameter class differences in the annual amount of foliage and fragments deposited. Foliage deposition rates ranged from just over 50 g m-2 year-1 in small diameter mountain hemlock stands to ???300 g m-2 year-1 for the three largest diameter classes of giant sequoia. The deposition rate for most woody fuel classes increased from the smallest diameter class stands to the largest diameter class stands. Woody fuel deposition rates varied among species as well. The rates for the smallest woody fuels ranged from 0.8 g m-2 year-1 for small diameter stands of Jeffrey pine to 126.9 g m-2 year-1 for very large diameter stands of mountain hemlock. Crown height and live crown ratio were the best predictors of fuel deposition rates for most fuel classes and species. Both characteristics reflect the amount of crown biomass including foliage and woody fuels. Relationships established in this study allow predictions of fuel loads to be made on a stand basis for each of these species under current and possible future conditions. These predictions can be used to

  20. Soil, plant, and transport influences on methane in a subalpine forest under high ultraviolet irradiance

    Directory of Open Access Journals (Sweden)

    D. Baer

    2009-07-01

    Full Text Available Recent studies have demonstrated direct methane emission from plant foliage under aerobic conditions, particularly under high ultraviolet (UV irradiance. We examined the potential importance of this phenomenon in a high-elevation conifer forest using micrometeorological techniques. Vertical profiles of methane and carbon dioxide in forest air were monitored every 2 h for 6 weeks in summer 2007. Day to day variability in above-canopy CH4 was high, with observed values in the range 1790 to 1910 nmol mol−1. High CH4 was correlated with high carbon monoxide and related to wind direction, consistent with pollutant transport from an urban area by a well-studied mountain-plain wind system. Soils were moderately dry during the study. Vertical gradients of CH4 were small but detectable day and night, both near the ground and within the vegetation canopy. Gradients near the ground were consistent with the forest soil being a net CH4 sink. Using scalar similarity with CO2, the magnitude of the summer soil CH4 sink was estimated at ~1.7 mg CH4 m−2 h−1, which is similar to other temperate forest upland soils. The high-elevation forest was naturally exposed to high UV irradiance under clear sky conditions, with observed peak UVB irradiance >2 W m−2. Gradients and means of CO2 within the canopy under daytime conditions showed net uptake of CO2 due to photosynthetic drawdown as expected. No evidence was found for a significant foliar CH4 source in the vegetation canopy, even under high UV conditions. While the possibility of a weak foliar source cannot be excluded given the observed soil sink, overall this subalpine forest was a net sink for atmospheric methane during the growing season.

  1. Ice duration, winter stratification, and mixing behavior of subalpine lakes in western Maine

    Science.gov (United States)

    Daly, J.; Adams, S.; Abrams, R.; Engel, B.

    2011-12-01

    The timing and duration of both winter and summer periods of stratification periods is not well known for subalpine ponds in the northeastern United States. The remote nature of many of these lakes precludes detailed manual monitoring during the winter and the visual identification of major ice phenological events. These lakes are associated with ecological niches at or near their local elevation maximum that may be at risk due to climate change; historic ice-out records for larger regional lakes indicates a significant trend toward earlier ice-out in response to climate warming. We are using low-cost data loggers to develop high-resolution records characterizing water temperature variability at multiple depths in fifteen lakes 600 - 1000 m elevation. These lakes are located along a 175 km transect in western Maine; most are along the Appalachian Trail. The loggers are recording sub-hourly water temperature and light at the surface, two meters depth, and the bottom of each lake. The timing and duration of winter stratification and ice cover on these lakes are determined by distinctive temperature patterns recorded by the data loggers. The onset of winter stratification is marked by the expected temperature inversion and a slowly increasing hypolimnetic temperature; ice-on follows and is represented by the transition from daily heating cycles to a steady temperature over several days as the ice freezes in around the near-surface logger and energy loss is accomplished through a phase change rather than a drop in temperature. Once the ice is established, temperatures recorded by the near-surface logger vary daily, and are frequently below freezing in response to changing air temperature. Evaluation of winter 2009-2011 records shows that the duration of winter stratification exceeds ice duration at nearly every site. The timing of the onset of stratification is nearly uniform across the study area within each year of data, suggesting a nearly simultaneous response to

  2. Estimating under-canopy ablation in a subalpine red-fir forest, southern Sierra Nevada, California

    Science.gov (United States)

    Kirchner, P. B.; Bales, R. C.; Rice, R.; Musselman, K. N.; Molotch, N. P.

    2010-12-01

    Snow ablation in forested environments is a result of the multi-component energy balance between the snow surface, radiation, topography, and vegetation. While these processes have been successfully described and modeled over small to moderate spatial extents the required data are available from few locations and existing models are computationally intensive. The problem of applying these principals to determining snow coverage for large spatial extents and frequent time steps, required by satellite observations, has not been solved. We present a simplified approach for determining a melt-out date based on modeled incident radiation, percent canopy cover, and leaf area index. This method was tested using results from instrumental data, field observations, and readily available spatial data sets by calibrating the MODIS Snow Covered Area and Grain size/albedo (MODSCAG) model from a snow-dominated site in the Wolverton basin Sequoia National Park; part of the Southern Sierra Nevada Critical Zone Observatory. The percent snow cover determined by MODSCAG from peak accumulation and melt out during the 2008 and 2009 water years were compared to ground observations of both forest gaps and under canopies. Ground based measurements indicated that under-canopy melt out of snow-covered area began earlier and ended 1 to 4 weeks after that indicated by satellite observations, which can only view snow in forest gaps. In our study ablation rates, snow cover duration, leaf area index, canopy closure, and Incoming short and long wave radiation were measured on north and southeast facing plots in a subalpine red fir forest. Results from regression analysis yield an R2=0.99 between modeled and measured short wave radiation and an R2=0.82 between leaf area index and the difference between open and under canopy thermal infrared radiation. Canopy cover and leaf area index were also found to be good predictors of observed melt rates and the melt off date of snow under tree canopies. This

  3. Long-term landscape changes in a subalpine spruce-fir forest in central Utah, USA

    Directory of Open Access Journals (Sweden)

    Jesse L. Morris1

    2015-12-01

    Full Text Available Background: In Western North America, increasing wildfire and outbreaks of native bark beetles have been mediated by warming climate conditions. Bioclimatic models forecast the loss of key high elevation species throughout the region. This study uses retrospective vegetation and fire history data to reconstruct the drivers of past disturbance and environmental change. Understanding the relationship among climate, antecedent disturbances, and the legacy effects of settlement-era logging can help identify the patterns and processes that create landscapes susceptible to bark beetle epidemics. Methods: Our analysis uses data from lake sediment cores, stand inventories, and historical records. Sediment cores were dated with radiometric techniques (14C and 210Pb/137Cs and subsampled for pollen and charcoal to maximize the temporal resolution during the historical period (1800 CE to present and to provide environmental baseline data (last 10,500 years. Pollen data for spruce were calibrated to carbon biomass (C t/ha using standard allometric equations and a transfer function. Charcoal samples were analyzed with statistical models to facilitate peak detection and determine fire recurrence intervals. Results: The Wasatch Plateau has been dominated by Engelmann spruce forests for the last ~10,500 years, with subalpine fir becoming more prominent since 6000 years ago. This landscape has experienced a dynamic fire regime, where burning events are more frequent and of higher magnitude during the last 3000 years. Two important disturbances have impacted Engelmann spruce in the historical period: 1 high-grade logging during the late 19th century; and (2 a high severity spruce beetle outbreak in the late 20th century that killed >90 % of mature spruce (>10 cm dbh. Conclusions: Our study shows that spruce-dominated forests in this region are resilient to a range of climate and disturbance regimes. Several lines of evidence suggest that 19th century logging

  4. Relaciones fenotípicas entre características de conformación con la habilidad de permanencia a los 36 meses en cabras Alpinas Relaciones fenotípicas entre características de conformación con la habilidad de permanencia a los 36 meses en cabras Alpinas

    Directory of Open Access Journals (Sweden)

    Lisa Shepard

    2012-02-01

    Full Text Available With the aim to study the relationships among stayability to 36 months of age with 14 type traits and first lactation milk yield in the Alpine breed, were used 1937 records of goats distributed in 155 flocks from the US American Dairy Goat Association. Data were analyzed using stepwise forward logistic regressions model. Flock effect resulted significant (p Se utilizaron 1937 registros de cabras de 155 rebaños pertenecientes a la American Dairy Goat Association de Estados Unidos con información de 14 características de conformación, así como de producción de leche de la primera lactancia (kg de la raza Alpina, con el objetivo de estudiar las relaciones que tienen estas con la habilidad de permanencia a los 36 meses de edad. Se utilizó un análisis de regresión logística hacia adelante en pasos. El efecto de rebaño resultó significativo (p

  5. Similarity of nutrient uptake and root dimensions of Engelmann spruce and subalpine fir at two contrasting sites in Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Yanai, R; McFarlane, K; Lucash, M; Kulpa, S; Wood, D

    2009-10-09

    Nutrient uptake capacity is an important parameter in modeling nutrient uptake by plants. Researchers commonly assume that uptake capacity measured for a species can be used across sites. We tested this assumption by measuring the nutrient uptake capacity of intact roots of Engelmann spruce (Picea engelmanni Parry) and subalpine fir (Abies lasiocarpa (Hook.) Nutt.) at Loch Vale Watershed and Fraser Experimental Forest in the Rocky Mountains of central Colorado. Roots still attached to the tree were exposed to one of three concentrations of nutrient solutions for time periods ranging from 1 to 96 hours, and solutions were analyzed for ammonium, nitrate, calcium, magnesium, and potassium. Surprisingly, the two species were indistinguishable in nutrient uptake within site for all nutrients (P > 0.25), but uptake rates differed by site. In general, nutrient uptake was higher at Fraser (P = 0.01, 0.15, 0.03, 0.18 for NH{sub 4}{sup +}, NO{sub 3}{sup -}, Ca{sup 2+}, and K{sup +}, respectively), which is west of the Continental Divide and has lower atmospheric deposition of N than Loch Vale. Mean uptake rates by site for ambient solution concentrations were 0.12 {micro}mol NH{sub 4}{sup +} g{sub fwt}{sup -1} h{sup -1}, 0.02 {micro}mol NO{sub 3}{sup -} g{sub fwt}{sup -1}, 0.21 {micro}mol Ca{sup 2+} g{sub fwt}{sup -1} h{sup -1}, and 0.01 {micro}mol Mg{sup 2+} g{sub fwt}{sup -1} h{sup -1} at Loch Vale, and 0.21 {micro}mol NH{sub 4}{sup +} f{sub fwt}{sup -1}h{sup -1}, 0.04 {micro}mol NO{sub 3}{sup -} g{sub fwt}{sup -1} h{sup -1}, 0.51 {micro}mol Ca{sup 2+}g{sub fwt}{sup -1}h{sup -1}, and 0.07 {micro}mol Mg{sup 2+} f{sub fwt}{sup -1}h{sup -1} at Fraser. The importance of site conditions in determining uptake capacity should not be overlooked when parameterizing nutrient uptake models. We also characterized the root morphology of these two species and compared them to other tree species we have measured at various sites in the northeastern USA. Engelman spruce and subalpine fir

  6. [Effects of snow pack on soil nitrogen transformation enzyme activities in a subalpine Abies faxioniana forest of western Sichuan, China].

    Science.gov (United States)

    Xiong, Li; Xu, Zhen-Feng; Wu, Fu-Zhong; Yang, Wan-Qin; Yin, Rui; Li, Zhi-Ping; Gou, Xiao-Lin; Tang, Shi-Shan

    2014-05-01

    This study characterized the dynamics of the activities of urease, nitrate reductase and nitrite reductase in both soil organic layer and mineral soil layer under three depths of snow pack (deep snowpack, moderate snowpack and shallow snowpack) over the three critical periods (snow formed period, snow stable period, and snow melt period) in the subalpine Abies faxoniana forest of western Sichuan in the winter of 2012 and 2013. Throughout the winter, soil temperature under deep snowpack increased by 46.2% and 26.2%, respectively in comparison with moderate snowpack and shallow snowpack. In general, the three nitrogen-related soil enzyme activities under shallow snowpack were 0.8 to 3.9 times of those under deep snowpack during the winter. In the beginning and thawing periods of seasonal snow pack, shallow snowpack significantly increased the activities of urease, nitrate and nitrite reductase enzyme in both soil organic layer and mineral soil layer. Although the activities of the studied enzymes in soil organic layer and mineral soil layer were observed to be higher than those under deep- and moderate snowpacks in deep winter, no significant difference was found under the three snow packs. Meanwhile, the effects of snowpack on the activities of the measured enzymes were related with season, soil layer and enzyme type. Significant variations of the activities of nitrogen-related enzymes were found in three critical periods over the winter, and the three measured soil enzymes were significantly higher in organic layer than in mineral layer. In addition, the activities of the three measured soil enzymes were closely related with temperature and moisture in soils. In conclusion, the decrease of snow pack induced by winter warming might increase the activities of soil enzymes related with nitrogen transformation and further stimulate the process of wintertime nitrogen transformation in soils of the subalpine forest.

  7. Characterization of Atmospheric Nitrate Dynamics in a Sub-Alpine Watershed Using Δ17O and δ15N

    Science.gov (United States)

    Bourgeois, I.; Savarino, J. P.; Clement, J. C.

    2015-12-01

    Remote subalpine ecosystems are usually characterized by nutrient-poor soils (Körner, 2004; Seastedt et al., 2004), making them particularly susceptible to undergo changes due to increased atmospheric N deposition (Vitousek et al., 1997; Preunkert et al., 2003). Using Δ17O, a conserved tracer of atmospheric nitrate (NO3 atm) (Michalski et al., 2004; Tsunogai et al., 2010), and δ15N, indicator of NO3 biological sources (Kendall, 1998; Casciotti et al., 2009), we measured the seasonal variations of NO3 atm stable isotopic composition and concentration in several streams and soils originating from two sub-alpine watersheds in the French Alps. Our objective was to investigate whether or not NO3 atm impacts the soil N biogeochemical cycle by increasing nutrients availability for plants and bacteria. We coupled streams and soils measurements with snow-pits sampling and aerosols collection at the Lautaret Pass, to better emphasize the correlation between atmospheric deposition, soil retention and watersheds effluents response. Our results reveal that different temporal dynamics govern our study site: stream measurements show that in spring, snowmelt results in a NO3 atm impulse, accounting for ca. 31 % of the total stream NO3 budget; on the opposite in autumn, NO3 atm accounts only for ca. 3 % of the total stream NO3 budget, highlighting the presence of a NO3 bacterial pool (nitrification). We also inferred from the observed Δ17O variations two distinct phenomena in the spring/summer season: a fast snow run-off and a slower snow-water percolation. The later is believed to affect most the soil N cycle as it directly increases available NO3. Measured soil leachates and extracts confirm this hypothesis and point out the potential importance of anthropogenic N deposition as on average 7 to 10 % of the soil solutions NO3 derives directly from the atmosphere.

  8. Pheno-anomalies of sub-alpine Vaccinium heaths in response to climatic variations

    Science.gov (United States)

    Puppi, Giovanna; Monti, Alessandra; Bonafede, Fausto; Vignodelli, Michele; Zanotti, Anna Letizia

    2014-05-01

    reduction in seed production and could have therefore be disadvantaged in turn-over. This hypothesis is consistent with the results on vegetation changes: in fact, the comparison of the actual vegetation with the historical observations in the same sites, shows a reduction of herb (Hemicryptophytes) diversity and cover in time. It is noteworthy that many of the declining species flower in the driest and hottest weeks of the year. In a climate-warming scenario, the low extension of these sub-alpine islands of the Apennines leads to a high extinction risk of the most sensible species. So, the monitoring of this vulnerable vegetation type seems necessary in order to detect the current trends and should be continued in the future. Puppi and Speranza 1980, Arch. Bot. Biogeogr. Ital. 56(3/4) Puppi et al. 1994, Fitosociologia 26: 63-79

  9. Impact of land use change on soil organic matter dynamics in subalpine grassland

    Science.gov (United States)

    Meyer, Stefanie; Leifeld, Jens; Bahn, Michael; Fuhrer, Jürg

    2010-05-01

    Information regarding the response of soil organic matter (SOM) in soils to past and expected future land use changes in the European Alps is scarce. Understanding this response requires knowledge of size and residence times of SOM fractions with distinct stabilities. In order to quantify differences between types of land use in the amount, distribution and turnover rates of soil organic carbon (SOC) in subalpine grassland soils, we used soil aggregate and SOM density fractionation in combination with 14C dating. Samples were taken along gradients of different types of land use from meadow (M) to pasture (P) and to abandoned grassland (A) in the Stubai Valley and in the Matsch Valley. Sampling sites in both areas were located at equal altitude (1880 m and 1820 m, respectively) with the same parent material and soil type, but the Matsch Valley receives 400-500 mm less annual rainfall. SOC stocks in the top 10 cm were 2.47 ± 0.32 (M), 2.75 ± 0.32 (P), and 2.50 ± 0.31 kg C/m2 (A) in the Stubai Valley and 2.25 ± 0.14 (M), 3.45 ± 0.22 (P), 3.16 ± 0.27 kg C/m2(A) in the Matsch Valley. Three aggregate size classes were separated by wet sieving: 2 mm. The light floating fraction (wPOM, ρ >1 g/cm3) was included in the analysis. Free (f-) and occluded particulate organic matter (oPOM) were isolated from each aggregate size class (ρ >1.6 g/cm3). At both locations, more than 80% of SOC was stored in small (0.25-2 mm) and large (>2 mm) macroaggregates, but no trend in relation to the different types of land use could be detected. The fraction of C in fPOM and in oPOM in all aggregate size classes was highest for soil from abandoned grasslands. The bulk soil of the abandoned site in the Stubai Valley showed a significantly higher share of fPOM-C and oPOM-C and a higher amount of wPOM-C as compared to the soil from managed grassland, whereas in the Matsch Valley pasture soil had a significantly higher wPOM-C content. At both sites, 13C natural abundance analyses revealed

  10. Autotrophic and Heterotrophic Controls over Winter Soil Carbon Cycling in a Subalpine Forest Ecosystem

    Science.gov (United States)

    Monson, R. K.; Scott-Denton, L. E.; Lipson, D. A.; Weintrub, M. N.; Rosenstiel, T. N.; Schmidt, S. K.; Williams, M. W.; Burns, S. P.; Delany, A. E.; Turnipseed, A. A.

    2005-12-01

    that interannual variation in winter ecosystem respiration is positively correlated to interannual variation in the spring snow depth. Years with a with a deeper spring snow pack exhibited higher soil temperatures, and concomitantly higher soil respiration rates. Given the recently reported decadal-scale trend in decreasing snow pack in the Western U.S., which is coupled to warm climate anomalies, our observations indicate the potential for higher wintertime soil carbon sequestration due to lower winter ecosystem respiration rates in subalpine forests. Our studies of processes beneath the winter snow pack demonstrate that contrary to previous assumptions, winter biogeochemical processing of soil organic matter is an important component of ecosystem carbon budgets. Despite low temperatures and an inactive plant rhizosphere, winter microbial communities and exoenzymes appear to be active, carbon substrates appear to be in relatively high abundance and soil respiration rates appear to be sensitive to seasonal and interannual winter climate variability.

  11. Use of passive UAS imaging to measure biophysical parameters in a southern Rocky Mountain subalpine forest

    Science.gov (United States)

    Caldwell, M. K.; Sloan, J.; Mladinich, C. S.; Wessman, C. A.

    2013-12-01

    Unmanned Aerial Systems (UAS) can provide detailed, fine spatial resolution imagery for ecological uses not otherwise obtainable through standard methods. The use of UAS imagery for ecology is a rapidly -evolving field, where the study of forest landscape ecology can be augmented using UAS imagery to scale and validate biophysical data from field measurements to spaceborne observations. High resolution imagery provided by UAS (30 cm2 pixels) offers detailed canopy cover and forest structure data in a time efficient and inexpensive manner. Using a GoPro Hero2 (2 mm focal length) camera mounted in the nose cone of a Raven unmanned system, we collected aerial and thermal data monthly during the summer 2013, over two subalpine forests in the Southern Rocky Mountains in Colorado. These forests are dominated by lodgepole pine (Pinus ponderosae) and have experienced insect-driven (primarily mountain pine beetle; MPB, Dendroctonus ponderosae) mortality. Objectives of this study include observations of forest health variables such as canopy water content (CWC) from thermal imagery and leaf area index (LAI), biomass and forest productivity from the Normalized Difference Vegetation Index (NDVI) from UAS imagery. Observations were, validated with ground measurements. Images were processed using a combination of AgiSoft Photoscan professional software and ENVI remote imaging software. We utilized the software Leaf Area Index Calculator (LAIC) developed by Córcoles et al. (2013) for calculating LAI from digital images and modified to conform to leaf area of needle-leaf trees as in Chen and Cihlar (1996) . LAIC uses a K-means cluster analysis to decipher the RGB levels for each pixel and distinguish between green aboveground vegetation and other materials, and project leaf area per unit of ground surface area (i.e. half total needle surface area per unit area). Preliminary LAIC UAS data shows summer average LAI was 3.8 in the most dense forest stands and 2.95 in less dense

  12. Dose-response characteristics of neonatal exposure to genistein on pituitary responsiveness to gonadotropin releasing hormone and volume of the sexually dimorphic nucleus of the preoptic area (SDN-POA) in postpubertal castrated female rats.

    Science.gov (United States)

    Faber, K A; Hughes, C L

    1993-01-01

    Estrogen exposure during critical periods of development promotes androgenization of the brain, which is reflected in altered morphology, behavior, and cyclic hormone secretion in females. Previous work in our laboratory demonstrated that neonatal female rats injected with pharmaceutical or naturally occurring estrogens had decreased GnRH-induced LH secretion and increased volume of the SDN-POA as 42 day castrates. The current experiment defines the dose-response characteristics of neonatal exposure to the isoflavonoid phytoestrogen genistein (G) on pituitary sensitivity to GnRH and SDN-POA volume. Litters of rat pups received subcutaneous injections of either corn oil, 1, 10, 100, 200, 400, 500, or 1000 micrograms of G on days 1 to 10 of life. The litters were ovariectomized and weaned on day 21. On day 42 blood was drawn from right atrial catheters immediately prior to, 5, 10, 15, and 30 min following a single injection of 50 ng/kg of GnRH. Only the 10 micrograms dose of G was associated with increased pituitary response to GnRH, while progressive increases in exposure levels of G were associated with decreasing LH secretion. The SDN-POA volume was increased in only the 500 micrograms and 1000 micrograms exposure groups compared to controls. The results confirm that low doses of G have nonandrogenizing, pituitary-sensitizing effects, while higher doses of G mimic the more typical effects of estrogens. The use of both morphologic and physiologic end points more completely defines the reproductive consequences of environmental estrogen exposure during critical periods of CNS development.

  13. Manejo orgânico e convencional do sistema de produção de cabras leiteiras Parda Alpina no Nordeste do Brasil

    Directory of Open Access Journals (Sweden)

    Wilma Emanuela Silva

    2015-10-01

    Full Text Available Objetivou-se neste trabalho comparar o manejo orgânico e convencional de um sistema de produção de caprinos leiteiros em Angicos, Rio Grande do Norte, Nordeste do Brasil. Foram utilizadas 26 cabras da Raça Parda Alpina em lactação, sendo 13 em manejo orgânico (MO e 13 em manejo convencional (MC. O delineamento experimental foi o inteiramente casualizado, com dois tratamentos e 13 repetições. Os animais do MO foram submetidos à sincronização de estro com efeito macho, tratamento à base de fitoterápicos contra endoparasitoses (Extrato de limão (Citrus Limonium e alho (Allium sativum, e no controle de mastite usando o Kit Embrapa de ordenha manual à base de alecrim pimenta (Lippia sidoides. No MC os animais receberam hormônios sintéticos (Promone-e®, Prólise® e Novormon® para a sincronização do estro, Ivermectina para endoparasitoses e álcool iodado para prevenção de mastite auxiliado pelo Kit Embrapa de ordenha manual. Não houve diferença significativa para os resultados de porcentagem de prenhezes, OPG, escores do FAMACHA©, composição físico-química do leite e Contagem de Células Somáticas (CCS nos dois tipos de manejo. No MO e MC as cabras apresentaram médias de percentagem de prenhezes positiva de 61,54% em ambos os sistemas. Os valores médios da contagem de ovos observados nos MO e MC foram de 24 e 35 de OPG, respectivamente. Pelo método FAMACHA© observou-se escores de 1 e 2; 2, 3 e 4 no MO e MC respectivamente. As cabras apresentaram pesos médios no MO (48,53 Kg e MC (55,92 Kg. A produção de leite, gordura, proteína, lactose, extrato seco total e extrato seco desengordurado no MO (0,971kg/dia; 2,210; 2,322; 3,306; 7,866; 5,566 foram ligeiramente superiores aos valores do MC (0,946 kg/dia 1,812; 1,812; 2,868; 6,74; 4,928. Para a CCS o MO (904.860 cel/mL e MC (1.020.520 cel/mL apresentaram valores próximos, estando o MO dentro dos valores aceitáveis para leite de cabra. O manejo orgânico foi

  14. [Dynamic changes of topsoil organic carbon in subalpine spruce plantation at different succession stages in western Sichuan Province].

    Science.gov (United States)

    Jiang, Fa-Yan; Sun, Hui; Lin, Bo; Liu, Qing

    2009-11-01

    Soil samples at 0-30 cm depth were collected from the primary spruce (Picea asperata) forest and its plantations at different succession stages (22-, 47-, and 65-year-old) in subalpine zone of western Sichuan Province to study the dynamic changes of soil organic carbon stock and labile organic carbon content. The soil total organic carbon (TOC) stocks in 0-10, 10-20, and 20-30 cm soil layers decreased from 95.87, 79.08, and 71.55 t x hm(-2) in 22-year-old plantation to 56.12, 34.75, and 31.06 t x hm(-2) in 65-year-old plantation, respectively, and the TOC stocks in these soil layers in 47 and 65-year-old plantations were less than those (88.08, 71.16 and 64.81 t x hm(-2), respectively) in primary forest. The easily oxidizable organic carbon (EOC) contents in 0-10, 10-20, and 20-30 cm soil layers decreased from 35.89, 26.91, and 26.00 g x kg(-1) in primary forest to 20.25, 14.50, and 12.36 g x kg L(-1) in 65-year-old plantation, the microbial biomass carbon (MBC) contents decreased from 524.44, 273.26, and 257.97 mg x kg(-1) in primary forest to 312.41, 186.95, and 152.18 mg x kg(-1) in 65-year-old plantation, and the particulate organic carbon (POC) contents decreased from 40.23, 27.10, and 19.55 g x kg(-1) in primary forest to 12.33, 7.31, and 5.32 g x kg(-1) in 65-year-old plantation, respectively. The results suggested that within the long succession period of primary P. asperata forest to its plantations in the subalpine zone of western Sichuan Province, soil TOC and labile organic carbon were in the state of net consumption.

  15. Subalpine Conifer Seedling Demographics: Species Responses to Climate Manipulations Across an Elevational Gradient at Niwot Ridge, Colorado

    Science.gov (United States)

    Castanha, C.; Germino, M. J.; Torn, M. S.; Ferrenberg, S.; Harte, J.; Kueppers, L. M.

    2010-12-01

    The effect of climate change on future ranges of treeline species is poorly understood. For example, it is not known whether trees will recruit into the alpine, above the current treeline, and whether population-level differences in trees will mediate range shifts. At Niwot Ridge, Colorado, we used common gardens and climate manipulations to test predictions that warming will lead to greater recruitment at and beyond the cold edge of these species ranges, and will reduce recruitment at the warm edge. Seed from local populations of limber pine and Englemann spruce was harvested and reciprocally planted in 3 experimental sites spanning an elevation gradient from lower subalpine forest (10,000’), to the upper subalpine treeline ecotone (11,000’), to the alpine tundra (11,300’). In Fall 2009 seeds were sown into 20 plots at each site. Overhead infrared heaters targeted increases in growing season surface soil temperature of 4-5°C. The heating treatment, which began in October 2009, was crossed with manual watering, which was initiated following snowmelt in 2010. Over the 2010 growing season, we surveyed seedling germination and mortality weekly. Germination began in early May at the forest site, in early June at the krummholz site, and in early July at the alpine site. Depending on the site and plot, heating accelerated germination by 1 to 4 weeks. Seed source elevation, species, and site all affected germination, with effects for the two species also depending on site. At all sites, lower elevation, warm-edge populations had higher germination rates than high-elevation, cool-edge populations, indicating a potential bottleneck for germination of the high elevation seed sources in the adjacent alpine tundra. At all sites, survival was generally higher for pine than for spruce. Watering tended to enhance pine germinant survival while heating tended to depress spruce germinant survival. Our results indicate that the alpine tundra, generally considered an

  16. Inter-annual climate variability and zooplankton: applying teleconnection indices to two deep subalpine lakes in Italy

    Directory of Open Access Journals (Sweden)

    Marina Manca

    2014-08-01

    Full Text Available Investigating relation between meteo-climatic indices and between-year variation in Daphnia population density and phenology is crucial for e.g. predicting impact of climate change on lake ecosystem structure and functioning. We tested whether and how two teleconnection indices calculated for the winter period, namely the East Atlantic pattern (EADJF and the Eastern Mediterranean Pattern (EMPDJF were correlated with Daphnia population growth in two Italian subalpine lakes, Garda and Maggiore. We investigated between-lake temporal coherence in: i water temperature within the water layer in which Daphnia is distributed; ii timing of Daphnia initial and spring maximum population density peak and iii the level of Daphnia spring maximum population density peak over an eleven-year period (1998-2008 of unchanged predation pressure by fish and invertebrates, and of common oligotrophy. Between-lake temporal coherence was high for an earlier start, an earlier, and lower, Daphnia population spring density peak after milder winters. Peak density level was coherently, positively correlated with soluble reactive phosphorus (SRP concentration. We hypothesized that Daphnia peak densities were related to atmospheric modes of variability in winter and to the degree of late winter mixing promoting replenishment of algal nutrients into upper water layers and phytoplankton growth, enhancing food availability and Daphnia fecundity, promoting Daphnia peak. 

  17. Equine Grazing in Managed Subalpine Wetlands: Effects on Arthropods and Plant Structure as a Function of Habitat

    Science.gov (United States)

    Holmquist, Jeffrey G.; Schmidt-Gengenbach, Jutta; Haultain, Sylvia A.

    2013-12-01

    Grazing management necessarily emphasizes the most spatially extensive vegetation assemblages, but landscapes are mosaics, often with more mesic vegetation types embedded within a matrix of drier vegetation. Our primary objective was to contrast effects of equine grazing on both subalpine vegetation structure and associated arthropods in a drier reed grass ( Calamagrostis muiriana) dominated habitat versus a wetter, more productive sedge habitat ( Carex utriculata). A second objective was to compare reed grass and sedge as habitats for fauna, irrespective of grazing. All work was done in Sequoia National Park (CA, USA), where detailed, long-term records of stock management were available. We sampled paired grazed and control wet meadows that contained both habitats. There were moderate negative effects of grazing on vegetation, and effects were greater in sedge than in reed grass. Conversely, negative grazing effects on arthropods, albeit limited, were greater in the drier reed grass, possibly due to microhabitat differences. The differing effects on plants and animals as a function of habitat emphasize the importance of considering both flora and fauna, as well as multiple habitat types, when making management decisions. Sedge supported twice the overall arthropod abundance of reed grass as well as greater diversity; hemipteran and dipteran taxa were particularly abundant in sedge. Given the greater grazing effects on sedge vegetation, greater habitat provision for terrestrial arthropods, and value as aquatic arthropod habitat, the wetter sedge assemblage is worthy of additional consideration by managers when planning for grazing and other aspects of land usage.

  18. The effects of winter recreation on alpine and subalpine fauna: a systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Chloe F Sato

    Full Text Available The ski industry is often perceived as having a negative impact on sensitive alpine and subalpine communities. However, empirical evidence of such impacts is lacking. We reviewed the available literature from the last 35 years to quantify the reported effects of winter recreation on faunal communities. Overall, using one-sample binomial tests ('sign tests' we found that the effects of all types of winter recreation-related disturbances (i.e. ski runs, resort infrastructure and winter tourism were more likely to be negative or have no effect, than be positive for wildlife. More specifically, in Europe, where the majority of the available research was conducted, the impacts of winter recreation were most often negative for fauna. In terms of specific taxa, birds and to a lesser extent mammals and arthropods, responded negatively to disturbance. Results from our meta-analysis confirmed the results from our binomial tests. Richness, abundance and diversity of fauna were lower in areas affected by winter recreation when compared with undisturbed areas. For most regions and taxa, however, empirical evidence remains too limited to identify clear impacts of winter recreation. We therefore conclude that the majority of ski resorts are operating in the absence of knowledge needed to inform effective strategies for biodiversity conservation and ecologically-sound management. Thus, there is an urgent need for more empirical research to be conducted throughout this increasingly threatened ecological community, especially given the indication from the available literature that fauna often respond negatively to winter recreation.

  19. Nutrient status in soil of Ski runs in the sub-alpine belt of Uludag Mountain, Bursa, Turkey.

    Science.gov (United States)

    Guleryuz, Gurcan; Kirmizi, Serap; Arslan, Hulya

    2010-01-01

    Large areas of land are disturbed in sensitive bio-diverse mountain environments by Skiruns. Restoration of vegetation on such disturbed mountain sites may be hampered by soil degradation but the severity and nature of the constraints is not well understood. This study was designed to compare the water holding and nutritional status of soil in three Ski runs which had different construction dates and disturbance levels, and the adjacent undisturbed site in the Abies bommuelleriana forest community in the sub-alpine belt of Uludag Mountain (Bithynian Olympus). The values of soil parameters were depressed in proportion to the disturbance level. Water holding capacity (WHC), total nitrogen (N), organic carbon (C) and calcium (Ca2+), magnesium (Mg2+) and potassium (K+) contents (mg kg(-1) dry weight) of soils in the Ski run which had the highest disturbance level were lower than that of the undisturbed adjacent sites. However the results indicated that the soil parameters were less degraded when secondary vegetation was growing on the disturbed areas.

  20. The Effects of Winter Recreation on Alpine and Subalpine Fauna: A Systematic Review and Meta-Analysis

    Science.gov (United States)

    Sato, Chloe F.; Wood, Jeff T.; Lindenmayer, David B.

    2013-01-01

    The ski industry is often perceived as having a negative impact on sensitive alpine and subalpine communities. However, empirical evidence of such impacts is lacking. We reviewed the available literature from the last 35 years to quantify the reported effects of winter recreation on faunal communities. Overall, using one-sample binomial tests (‘sign tests’) we found that the effects of all types of winter recreation-related disturbances (i.e. ski runs, resort infrastructure and winter tourism) were more likely to be negative or have no effect, than be positive for wildlife. More specifically, in Europe, where the majority of the available research was conducted, the impacts of winter recreation were most often negative for fauna. In terms of specific taxa, birds and to a lesser extent mammals and arthropods, responded negatively to disturbance. Results from our meta-analysis confirmed the results from our binomial tests. Richness, abundance and diversity of fauna were lower in areas affected by winter recreation when compared with undisturbed areas. For most regions and taxa, however, empirical evidence remains too limited to identify clear impacts of winter recreation. We therefore conclude that the majority of ski resorts are operating in the absence of knowledge needed to inform effective strategies for biodiversity conservation and ecologically-sound management. Thus, there is an urgent need for more empirical research to be conducted throughout this increasingly threatened ecological community, especially given the indication from the available literature that fauna often respond negatively to winter recreation. PMID:23691190

  1. Using time scales to characterize phytoplankton assemblages in a deep subalpine lake during the thermal stratification period: Lake Iseo, Italy

    Science.gov (United States)

    Marti, Clelia Luisa; Imberger, Jörg; Garibaldi, Letizia; Leoni, Barbara

    2016-03-01

    A combination of field observations and 3-D hydrodynamic simulations were used to identify the phytoplankton species and to estimate the various time scales of the dominant physical and biological processes in Lake Iseo, a deep subalpine lake located in northern Italy, during a stratified period (July 2010). By ordering the rate processes time scales, we derive a phytoplankton patch categorization and growth interpretation that provides a general framework for the spatial distribution of phytoplankton concentration in Lake Iseo and illuminates the characteristics of their ecological niches. The results show that the diurnal surface layer was well mixed, received strong diurnal radiation, had low phosphorus concentrations and the phytoplankton biomass was sustained by the green alga Sphaerocystis schroeterii. The vertical mixing time scales were much shorter than horizontal mixing time scales causing a depth-uniform chlorophyll a concentration. The horizontal patch scale was determined by horizontal dispersion balancing the phytoplankton growth time scale, dictating the success of the observed green algae. The strongly stratified nutrient-rich metalimnion had mild light conditions and Diatoma elongatum and Planktothrix rubescens made up the largest proportions of the total phytoplankton biomass at the intermediate and deeper metalimnetic layers. The vertical transport time scales were much shorter than horizontal transport and vertical dispersion leading to growth niche for the observed phytoplankton. The study showed that time-scale hierarchy mandates the essential phytoplankton attributes or traits for success in a particular section of the water column and/or water body.

  2. Virtual disjunct eddy covariance measurements of organic compound fluxes from a subalpine forest using proton transfer reaction mass spectrometry

    Directory of Open Access Journals (Sweden)

    T. G. Karl

    2002-01-01

    Full Text Available A `virtual' disjunct eddy covariance (vDEC device was tested with field measurements of biogenic VOC fluxes at a subalpine forest site in the Rocky Mountains of the USA. A PTR-MS instrument was used as the VOC sensor. Daily peak emission fluxes of 2-methyl-3-buten-2-ol (MBO, methanol, acetone and acetaldehyde were around 1.5, 1, 0.8 and 0.4 mg m-2 h-1, respectively. High pass filtering due to long sampling lines was investigated in laboratory experiments, and suggested that VOC losses in PTFA lines are generally governed by diffusion laws. Memory effects and surface reactions did not seem to play a dominant role. Model estimates of MBO fluxes compared well with measured fluxes. The results also suggest that latent heat and sensible heat fluxes are reasonably well correlated with VOC fluxes and could be used to predict variations in VOC emissions. The release of MBO, methanol, acetone and acetaldehyde resulted in significant change of tropospheric oxidant levels and a 10--40% increase in ozone levels, as inferred from a photochemical box model. We conclude that vDEC with a PTR-MS instrument is a versatile tool for simultaneous field analysis of multiple VOC fluxes.

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

    Science.gov (United States)

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

    2015-01-01

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

  4. The effects of winter recreation on alpine and subalpine fauna: a systematic review and meta-analysis.

    Science.gov (United States)

    Sato, Chloe F; Wood, Jeff T; Lindenmayer, David B

    2013-01-01

    The ski industry is often perceived as having a negative impact on sensitive alpine and subalpine communities. However, empirical evidence of such impacts is lacking. We reviewed the available literature from the last 35 years to quantify the reported effects of winter recreation on faunal communities. Overall, using one-sample binomial tests ('sign tests') we found that the effects of all types of winter recreation-related disturbances (i.e. ski runs, resort infrastructure and winter tourism) were more likely to be negative or have no effect, than be positive for wildlife. More specifically, in Europe, where the majority of the available research was conducted, the impacts of winter recreation were most often negative for fauna. In terms of specific taxa, birds and to a lesser extent mammals and arthropods, responded negatively to disturbance. Results from our meta-analysis confirmed the results from our binomial tests. Richness, abundance and diversity of fauna were lower in areas affected by winter recreation when compared with undisturbed areas. For most regions and taxa, however, empirical evidence remains too limited to identify clear impacts of winter recreation. We therefore conclude that the majority of ski resorts are operating in the absence of knowledge needed to inform effective strategies for biodiversity conservation and ecologically-sound management. Thus, there is an urgent need for more empirical research to be conducted throughout this increasingly threatened ecological community, especially given the indication from the available literature that fauna often respond negatively to winter recreation.

  5. Mercury in forest mushrooms and topsoil from the Yunnan highlands and the subalpine region of the Minya Konka summit in the Eastern Tibetan Plateau.

    Science.gov (United States)

    Falandysz, Jerzy; Saba, Martyna; Liu, Hong-Gao; Li, Tao; Wang, Ji-Peng; Wiejak, Anna; Zhang, Ji; Wang, Yuan-Zhong; Zhang, Dan

    2016-12-01

    This study aimed to investigate and discuss the occurrence and accumulation of mercury in the fruiting bodies of wild-growing fungi (Macromycetes) collected from montane forests in two regions of southwestern China with differences in soil geochemistry, climate and geographical conditions. Fungal mycelia in soils of the subalpine region of the Minya Konka (Gongga Mountain) in Sichuan and in the highlands of Yunnan efficiently accumulated mercury in fruiting bodies (mushrooms). The examined sites in Yunnan with highly mineralized red and yellow soils showed Hg contents ranging from 0.066 to 0.28 mg kg -1 dry biomass (db) which is roughly similar to the results obtained for samples collected from sites with dark soils relatively rich in organic matter from a remote, the subalpine region of Minya Konka. Due to the remoteness of the subalpine section of Minya Konka, as well as its elevation and climate, airborne mercury from long-range transport could be deposited preferentially on the topsoil and the Hg levels determined in soil samples taken beneath the fruiting bodies were up to 0.48 mg kg -1 dry matter. In Yunnan, with polymetallic soils (Circum-Pacific Mercuriferous Belt), Amanita mushrooms showed mercury in caps of fruiting bodies of up to 7.3 mg kg -1 dry biomass. Geogenic Hg from the mercuriferous belt seems to be the overriding source of mercury accumulated in mushrooms foraged in the regions of Yunnan, while long-range atmospheric transport and subsequent deposition are the mercury sources for specimens foraged in the region of Minya Konka.

  6. Diphyllobothrium latum (Cestoda: Diphyllobothriidea in perch (Perca fluviatilis in three sub-alpine lakes: influence of biotic and abiotic factors on prevalence

    Directory of Open Access Journals (Sweden)

    Orlando PETRINI

    2009-08-01

    Full Text Available In recent years, human diphyllobothriosis has staged a comeback in Swiss, French and Italian sub-alpine regions. The main putative infective source of the causative agent (the tapeworm Diphyllobothrium latum in these areas is perch (Perca fluviatilis. Therefore, the occurrence of D. latum in this fish species was investigated between 2005 and 2008 in the sub-alpine lakes Maggiore, Lugano and Geneva. Prevalence in fish of Lake Maggiore was 14% (n = 880. In Lake Geneva, 5.1% fillets (n = 532 were infected, whereas perch from Lake Lugano were free from the parasite. These results are discussed in relation to previous studies. Data on fish size and weight indicate that infection of perch by D. latum is independent of age and sex. Abiotic factors considered critical for D. latum life cycle (water temperature and oxygen concentration characterize the three basins and were related to their infestation frequencies. The presence of this parasite was most likely favoured by warmer, well oxygenated waters. Previous studies indicate that the lake’s trophic state (i.e. content of total phosphorus influenced the availability of the first intermediate hosts (copepods of some pseudophyllideans. In our study, no correlation was observed between the amount of phosphorus and the number of copepods in populations of zooplankton. Nevertheless, the trophic states of the three lakes seemed to affect the degree of infection in fish. In conclusion, at least in sub-alpine lakes, abiotic factors such as water temperature, oxygenation and trophic state seem to have an influence on maintaining or preventing perch infection with D. latum.

  7. Winter ecology of a subalpine grassland: Effects of snow removal on soil respiration, microbial structure and function.

    Science.gov (United States)

    Gavazov, Konstantin; Ingrisch, Johannes; Hasibeder, Roland; Mills, Robert T E; Buttler, Alexandre; Gleixner, Gerd; Pumpanen, Jukka; Bahn, Michael

    2017-07-15

    Seasonal snow cover provides essential insulation for mountain ecosystems, but expected changes in precipitation patterns and snow cover duration due to global warming can influence the activity of soil microbial communities. In turn, these changes have the potential to create new dynamics of soil organic matter cycling. To assess the effects of experimental snow removal and advanced spring conditions on soil carbon (C) and nitrogen (N) dynamics, and on the biomass and structure of soil microbial communities, we performed an in situ study in a subalpine grassland in the Austrian Alps, in conjunction with soil incubations under controlled conditions. We found substantial winter C-mineralisation and high accumulation of inorganic and organic N in the topsoil, peaking at snowmelt. Soil microbial biomass doubled under the snow, paralleled by a fivefold increase in its C:N ratio, but no apparent change in its bacteria-dominated community structure. Snow removal led to a series of mild freeze-thaw cycles, which had minor effects on in situ soil CO2 production and N mineralisation. Incubated soil under advanced spring conditions, however, revealed an impaired microbial metabolism shortly after snow removal, characterised by a limited capacity for C-mineralisation of both fresh plant-derived substrates and existing soil organic matter (SOM), leading to reduced priming effects. This effect was transient and the observed recovery in microbial respiration and SOM priming towards the end of the winter season indicated microbial resilience to short-lived freeze-thaw disturbance under field conditions. Bacteria showed a higher potential for uptake of plant-derived C substrates during this recovery phase. The observed temporary loss in microbial C-mineralisation capacity and the promotion of bacteria over fungi can likely impede winter SOM cycling in mountain grasslands under recurrent winter climate change events, with plausible implications for soil nutrient availability and

  8. Thirty Years of Change in Subalpine Forest Cover from Landsat Image Analysis in the Sierra Nevada Mountains of California

    Science.gov (United States)

    Potter, Christopher

    2015-01-01

    Landsat imagery was analyzed to understand changes in subalpine forest stands since the mid-1980s in the Sierra-Nevada region of California. At locations where long-term plot measurements have shown that stands are becoming denser in the number of small tree stems (compared to the early 1930s), the 30-year analysis of Landsat greenness index (NDVI) indicated that no consistent increases in canopy leaf cover have occurred at these same locations since the mid-1980s. Interannual variations in stand NDVI closely followed snow accumulation amounts recorded at nearby stations. In contrast, at eastern Sierra whitebark pine stand locations where it has been observed that widespread tree mortality has occurred, decreasing NDVI trends over the past 5-10 years were consistent with rapid loss of forest canopy cover. Landsat imagery was further analyzed to understand patterns of post-wildfire vegetation recovery, focusing on high burn severity (HBS) patches within burned areas dating from the late 1940s. Analysis of landscape metrics showed that the percentage of total HBS area comprised by the largest patch of recovered woody cover was relatively small in all fires that occurred since 1995, but increased rapidly with time since fire. Patch complexity of recovered woody cover decreased notably after more than 50 years of regrowth, but was not readily associated with time for fires that occurred since the mid 1990s. The aggregation level of patches with recovery of woody cover increased steadily with time since fire. The study approach using satellite remote sensing can be expanded to assess the consequences of stand-replacing wildfires in all forests of the region.

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

    Science.gov (United States)

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

    2015-06-01

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

  10. Mycorrhiza-plant colonization patterns on a subalpine glacier forefront as a model system of primary succession.

    Science.gov (United States)

    Cázares, Efrén; Trappe, James M; Jumpponen, Ari

    2005-09-01

    Lyman glacier in the North Cascades Mountains of Washington has a subalpine forefront characterized by a well-developed terminal moraine, inconspicuous successional moraines, fluting, and outwash. These deposits were depleted of symbiotic fungi when first exposed but colonized by them over time after exposure. Four major groups of plant species in this system are (1) mycorrhiza-independent or facultative mycotrophic, (2) dependent on arbuscular mycorrhizae (AM) (3) dependent on ericoid mycorrhiza (ERM) or ectomycorrhizae (EM), and (4) colonized by dark-septate (DS) endophytes. We hypothesized that availability of mycorrhizal propagules was related to the success of mycorrhiza-dependent plants in colonizing new substrates in naturally evolved ecosystems. To test this hypothesis roots samples of 66 plant species were examined for mycorrhizal colonization. The plants were sampled from communities at increasing distances from the glacier terminus to compare the newest communities with successively older ones. Long established, secondary successional dry meadow communities adjacent to the glacier forefront, and nearby high alpine communities were sampled for comparison. DS were common on most plant species on the forefront. Nonmycorrhizal plants predominated in the earlier successional sites, whereas the proportion of mycorrhizal plants generally increased with age of community. AM were present, mostly at low levels, and nearly absent in two sites of the forefront. ERM were present in all species of Ericaceae sampled, and EM in all species of Pinaceae and Salicaceae. Roots of plants in the long established meadow and heath communities adjacent to the forefront and the high alpine community all had one or another of the colonization types, with DS and AM predominating.

  11. LOS DÍAS LARGOS ARTIFICIALES CONSTANTES INCREMENTAN LA PRODUCCIÓN LÁCTEA EN LAS CABRAS ALPINAS DEL NORTE DE MÉXICO

    Directory of Open Access Journals (Sweden)

    Evaristo Carrillo

    2010-11-01

    Full Text Available Para determinar si la aplicación de días largos artificiales durante el invierno y primavera aumenta la producción láctea de las cabras Alpinas del norte de México, un grupo testigo (GT; n=14, fue expuesto a las variaciones naturales del fotoperiodo de la región durante todo el estudio (10 h y 19 m en el solsticio de invierno y 13 h con 41 m durante el solsticio de verano, mientras otro grupo experimental (GE; n=15, se sujetó a un tratamiento de días largos constantes (16 h de luz/8 h de oscuridad del 1 de diciembre al 19 de abril. La producción de leche al inicio del estudio (día 0 = 45 ± 0.6 días posparto fue similar en los dos grupos (P>0.05, mientras que del día 14 hasta el día 112 del estudio, fue diferente entre los dos grupos (3.2 ± 0.07 vs. 2.7 ± 0.06 lts/día/animal GE vs. GT; P

  12. Ash, Asterionella, and Anglers: A Paleolimnological Approach to Understanding Anthropogenic and Volcanogenic Disturbances in a Small Sub-Alpine Watershed

    Science.gov (United States)

    Howard, K. L.; Noble, P. J.

    2014-12-01

    This poster summarizes geochemical, biological, hydrological, and watershed data that characterize Manzanita Lake, a small sub-alpine catchment in Lassen Volcanic National Park, CA. The future objective is to use characteristics of this system to interpret variations in diatom and sediment composition dating back to the 1914 Mt. Lassen eruption from a recently recovered lake core. Manzanita Lake is a small (0.18 km2) lake with a ~30 km2 watershed area situated on the northwest flank of Mt. Lassen, one of the most active Cascade volcanoes, and is a valuable recreational spot for anglers and visitors. Hydraulic residence time is short; roughly 119 days, and is derived from lake volume (1.0 X 106m3) and estimates of stream inflow (~6 ft3/sec) and outflow (~3 ft3/sec) that were made from May 2014 sampling data. Limnological sampling in 2012-2014 suggests that Manzanita Lake exhibits stable thermal stratification in the summer months, which is unusual given the shallow depth (~10m), but possibly supported by the morphometry of the lake basin and inputs of cold snowmelt from the flank of Lassen Peak. The lake is a moderately conductive (100-114 μS), mesotrophic system with secchi depths ranging from 8m to the bottom (~10m). Total phosphorus (TP) ranges from 15-25 ppb and dissolved inorganic nitrogen (DIN) from 2-15 ppb, with ammonium in the epilimnion being the largest contributor. A high concentration of silica (Si) in surface water inputs (34 mg/L) to Manzanita Lake likely reflects the rhyodacitic bedrock geology and large drainage ratio (164) of the watershed. Variations in Si concentration in the lake seem to be coupled with diatom production. During the sampling period Manzanita Lake is has been dominated by diatom blooms throughout the summer and fall months. There is a seasonal succession in the diatom species present, with abundant Asterionella formosa in the spring, transitioning to abundant Fragilaria crotonensis in the summer months, to a mixed dominance of

  13. Spatio-seasonal variability in dissolved organic matter optical properties and its bioavailability in a subalpine lake

    Science.gov (United States)

    Stadler, Masumi; Ejarque, Elisabet; Kainz, Martin J.

    2017-04-01

    Allochthonous and autochothonous dissolved organic matter (DOM) in lakes mainly originate from terrestrial and aquatic primary production, respectively. Due to their differing biochemical composition the degradability of DOM by microorganisms is expected to vary. The carbon use efficiency of bacteria and DOM biodegradability determine whether the consumed DOM is incorporated into microbial biomass or respired to CO2 and ultimately emitted into the atmosphere. Thus, understanding the interaction of biodegradable DOM and its consumers is crucial to increase our knowledge on the role of lakes in the global carbon cycling. However, interactions of specific aquatic DOM signatures and the microbial population still remain widely debated. The aim of this study was to explore how DOM biodegradability changes along a stream-lake continuum at different seasons of the year. We monitored DOM quantity and its optical properties, inorganic nutrients, CO2 and bacterial growth over 20 days in dark bioassays with water from the inflow, outflow and at three layers of an oligotrophic subalpine lake. Preliminary results reveal highest microbial abundance in the metalimnion in winter and summer (0.7 106 and 2.5 106 cells mL-1, respectively) and the inflow in spring and autumn (1 106 and 1.4 106 cells mL-1, respectively) after 20 days. Surprisingly, with the exception of winter samples final inflow bacterial abundance results high, despite its lowest initial natural cell concentration, providing evidence for effective utilisation of terrestrial DOM, even with its high humic signature as indicated by the humification index (HIX). Nonetheless, after a microbial biomass peak with the inflow yielding mostly highest after three days, at the final experimental stage microbial biomass does only marginally differ between all sites with the exception of autumn samples where outflow and metalimnion turn out most productive. Even though the DOM of all lake sites and the lake outflow were

  14. Drought induced changes of plant belowground carbon allocation affect soil microbial community function in a subalpine meadow

    Science.gov (United States)

    Fuchslueger, L.; Bahn, M.; Fritz, K.; Hasibeder, R.; Richter, A.

    2012-12-01

    There is growing evidence that climate extremes may affect ecosystem carbon dynamics more strongly than gradual changes in temperatures or precipitation. Climate projections suggest more frequent heat waves accompanied by extreme drought periods in many parts of Europe, including the Alps. Drought is considered to decrease plant C uptake and turnover, which may in turn decrease belowground C allocation and potentially has significant consequences for microbial community composition and functioning. However, information on effects of drought on C dynamics at the plant-soil interface in real ecosystems is still scarce. Our study aimed at understanding how summer drought affects soil microbial community composition and the uptake of recently assimilated plant C by different microbial groups in grassland. We hypothesized that under drought 1) the microbial community shifts, fungi being less affected than bacteria, 2) plants decrease belowground C allocation, which further reduces C transfer to soil microbes and 3) the combined effects of belowground C allocation, reduced soil C transport due to reduced soil moisture and shift in microbial communities cause an accumulation of extractable organic C in the soil. Our study was conducted as part of a rain-exclusion experiment in a subalpine meadow in the Austrian Central Alps. After eight weeks of rain exclusion we pulse labelled drought and control plots with 13CO2 and traced C in plant biomass, extractable organic C (EOC) and soil microbial communities using phospholipid fatty acids (PLFA). Drought induced a shift of the microbial community composition: gram-positive bacteria became more dominant, whereas gram-negative bacteria were not affected by drought. Also the relative abundance of fungal biomass was not affected by drought. While total microbial biomass (as estimated by total microbial PLFA content) increased during drought, less 13C was taken up. This reduction was pronounced for bacterial biomarkers. It reflects

  15. Soil attributes and microclimate are important drivers of initial deadwood decay in sub-alpine Norway spruce forests.

    Science.gov (United States)

    Fravolini, Giulia; Egli, Markus; Derungs, Curdin; Cherubini, Paolo; Ascher-Jenull, Judith; Gómez-Brandón, María; Bardelli, Tommaso; Tognetti, Roberto; Lombardi, Fabio; Marchetti, Marco

    2016-11-01

    Deadwood is known to significantly contribute to global terrestrial carbon stocks and carbon cycling, but its decay dynamics are still not thoroughly understood. Although the chemistry of deadwood has been studied as a function of decay stage in temperate to subalpine environments, it has generally not been related to time. We therefore studied the decay (mass of deadwood, cellulose and lignin) of equal-sized blocks of Picea abies wood in soil-mesocosms over two years in the Italian Alps. The 8 sites selected were along an altitudinal sequence, reflecting different climate zones. In addition, the effect of exposure (north- and south-facing slopes) was taken into account. The decay dynamics of the mass of deadwood, cellulose and lignin were related to soil parameters (pH, soil texture, moisture, temperature) and climatic data. The decay rate constants of Picea abies deadwood were low (on average between 0.039 and 0.040y(-1)) and of lignin close to zero (or not detectable), while cellulose reacted much faster with average decay rate constants between 0.110 and 0.117y(-1). Our field experiments showed that local scale factors, such as soil parameters and topographic properties, influenced the decay process: higher soil moisture and clay content along with a lower pH seemed to accelerate wood decay. Interestingly, air temperature negatively correlated with decay rates or positively with the amount of wood components on south-facing sites. It exerted its influence rather on moisture availability, i.e. the lower the temperature the higher the moisture availability. Topographic features were also relevant with generally slower decay processes on south-facing sites than on north-facing sites owing to the drier conditions, the higher pH and the lower weathering state of the soils (less clay minerals). This study highlights the importance of a multifactorial consideration of edaphic parameters to unravel the complex dynamics of initial wood decay. Copyright © 2016 Elsevier

  16. The influence of changes in soil moisture in association with geomorphic change on the formation of a subalpine coniferous forest on Mt. Akita-Komagatake, northern Japan

    Science.gov (United States)

    Konno, A.

    2015-12-01

    The coniferous forest (largely composed of Abies mariesii) is presently the typical vegetation of the subalpine zone in Japan. Pollen analysis revealed that few A. mariesii were present during the last glacial period, and the species began to expand to the subalpine zone during the Holocene (Morita, 1992). However, on Mt. Akita-Komagatake in northern Japan, the expected predominance of A. mariesii is not extensively observed, and the predominant vegetation is instead the dwarf bamboo (Sasa kurilensis). It is unknown why the area under coniferous forest is small in this region. Therefore, I examined this issue from the perspectives of (1) distribution of vegetation, (2) geomorphology, (3) soil moisture, and (4) vegetation history. (1) Precise digital elevation model data and photographic interpretation showed that this coniferous forest was densely distributed in a flat segment considered to be formed by a landslide; (2) this landslide is thought to have occurred up to 3,699 ± 26 yr BP because a boring-core specimen from the landslide included the AK-3 tephra layer (2,300-2,800 yr BP: Wachi et al, 1997) and the radiocarbon date of the lowermost humic soil layer was 3,699 ± 26 yr BP; (3) the soil in the forest area had higher volumetric water content than that in the non-forest area; and (4) phytolith analysis revealed that the main species in the study site was initially dwarf bamboo, but coniferous forest replaced it after the Towada-a tephra (1035 cal. BP, Machida and Arai, 1992) layer fell. These results suggest that soil water conditions changed because of the formation of the flat segment by the landslide, and the coniferous forest was consequently established. However, the landslide only indirectly affected the formation of the coniferous forest, because the forest developed over several thousand years after the landslide occurred. In other words, more direct reasons for the establishment of the coniferous forest may involve changes in soil moisture. This

  17. Desempenho reprodutivo de cabras alpinas tratadas com hCG cinco dias após o acasalamento Reproductive performance of alpine goats treated with hCG five days after breeding

    Directory of Open Access Journals (Sweden)

    Jeferson Ferreira da Fonseca

    2005-04-01

    Full Text Available Objetivou-se com este estudo avaliar o efeito da administração de hCG sobre o desempenho reprodutivo de cabras Alpinas durante a estação de acasalamento natural. Trinta e duas fêmeas nulíparas e 124 lactantes, após a identificação de estro e acasalamento, foram aleatoriamente divididas, de acordo com a categoria, em dois tratamentos. Em T1 (n=75 e T2 (n=81, os animais receberam 1 mL de solução salina ou 250 UI de hCG, respectivamente, por via intramuscular cinco dias após o acasalamento. A gestação foi verificada por ultra-sonografia transabdominal (probe de 3,5 MHz nos dias 35 e 70 após o acasalamento, para detecção e confirmação da gestação, respectivamente. As taxas de gestação não diferiram entre T1 (86,7% e T2 (70,6% para nulíparas e T1 (78,3 % e T2 (84,4 % para lactantes. Não houve diferença entre a taxa de parição (75,0 e 75,7%, o período de gestação (150,47 e 150,80 dias e a prolificidade (1,75 e 1,80 fetos entre os animais do T1 e T2, respectivamente. A prolificidade foi superior em cabras lactantes (1,90 que em nulíparas (1,41. A administração de hCG cinco dias após o acasalamento não elevou o desempenho reprodutivo em cabras da raça Alpina.The effect of hCG administration on reproductive performance of Alpine goats during the natural breeding season was evaluated. Thirty-two nulliparous and 124 lactating goats, after estrus identification and breeding, were randomly assigned according to the categories to two treatments. In T1 (n=75 and T2 (n=81 the animals received 1 mL of saline solution or 250 IU of hCG intramuscularly, respectively, five days after breeding. Pregnancy was detected and confirmed on days 35 and 70 after breeding by transabdominal ultrasonography (3.5 MHz probe, respectively. Pregnancy rate did not differ between T1 (86.7 % and T2 (70.6% for nulliparous and T1 (78.3% and T2 (84.4% for lactating does. There were no differences for kidding rate (75.0 and 75.7%, gestation period

  18. High genetic differentiation in the alpine plant Campanula alpina Jacq. (Campanulaceae): evidence for glacial survival in several Carpathian regions and long-term isolation between the Carpathians and the Alps.

    Science.gov (United States)

    Ronikier, M; Cieślak, E; Korbecka, G

    2008-04-01

    A survey of amplified fragment length polymorphism (AFLP) and chloroplast DNA (cpDNA) variation was conducted to elucidate the phylogeography of Campanula alpina, a key species of silicicolous alpine grasslands in the Carpathians with a disjunct distribution in the Eastern European Alps. The Carpathians experienced a different glacial history from the Alps: local glaciers were present only in the highest massifs, while alpine habitats extended over larger areas related to their present distribution in this region. We asked: (i) whether in the Carpathians a high-mountain plant exhibits a complex phylogeographical structure or rather signatures of recent migrations, and (ii) whether the disjunct part of the species' distribution in the Alps resulted from a recent colonization from the Carpathians or from a restricted expansion from separate Eastern Alpine refugia. Our study revealed a clear phylogeographical pattern in AFLPs supported by congruent groups of distinct cpDNA haplotypes. Highest genetic differentiation was observed between the Alps and the Carpathians, indicating a long-term isolation between populations from these two mountain ranges. Further genetic division within the Carpathians suggests that current species' distribution is composed of several groups which have been isolated from each other for a long period. One genetic break separates Western from Southeastern Carpathian material, which is in line with a classical biogeographical boundary. A further, strongly supported genetic group was identified at the southwestern edge of the Carpathian arch. In the Eastern Alps, genetic traces of glacial survival in separate refugial areas in the calcareous northern part and the siliceous central part were found.

  19. Responses of assemblages of Orthoptera to management and use of ski slopes on upper sub-alpine meadows in the Austrian Alps.

    Science.gov (United States)

    Illich, Ingeborg P; Haslett, John R

    1994-05-01

    The Orthoptera assemblages occurring on sub-alpine ski slopes were compared with those found on neighbouring unskied meadows by making frequent transect counts at two pairs of sites in the Gastein valley in the Austrian Central Alps. On one of the ski slopes no Orthoptera were present, although two species were abundant on the control meadow a few meters away. On the second ski slope, the Orthoptera assemblage exhibited reduced species richness, lower densities of individuals and a generally accelerated rate of nymphal development compared to the control meadow populations. These results may be explained in terms of the changed habitat conditions on the ski slopes and the known biologies of the species concerned. The implications of the findings for winter tourism management in high altitude ecosystems are briefly discussed.

  20. Effects of elevated CO₂ and temperature on photosynthesis and leaf traits of an understory dwarf bamboo in subalpine forest zone, China.

    Science.gov (United States)

    Li, Yongping; Zhang, Yuanbin; Zhang, Xiaolu; Korpelainen, Helena; Berninger, Frank; Li, Chunyang

    2013-06-01

    The dwarf bamboo (Fargesia rufa Yi), growing understory in subalpine dark coniferous forest, is one of the main foods for giant panda, and it influences the regeneration of subalpine coniferous forests in southwestern China. To investigate the effects of elevated CO₂, temperature and their combination, the dwarf bamboo plantlets were exposed to two CO₂ regimes (ambient and double ambient CO₂ concentration) and two temperatures (ambient and +2.2°C) in growth chambers. Gas exchange, leaf traits and carbohydrates concentration were measured after the 150-day experiment. Elevated CO₂ significantly increased the net photosynthetic rate (Anet ), intrinsic water-use efficiency (WUEi ) and carbon isotope composition (δ¹³C) and decreased stomatal conductance (g(s)) and total chlorophyll concentration based on mass (Chl(m)) and area (Chl(a)). On the other hand, elevated CO₂ decreased specific leaf area (SLA), which was increased by elevated temperature. Elevated CO₂ also increased foliar carbon concentration based on mass (C(m)) and area (C(a)), nitrogen concentration based on area (N(a)), carbohydrates concentration (i.e. sucrose, sugar, starch and non-structural carbohydrates) and the slope of the A(net)-N(a) relationship. However, elevated temperature decreased C(m), C(a) and N(a). The combination of elevated CO₂ and temperature hardly affected SLA, C(m), C(a), N(m), N(a), Chl(m) and Chl(a). Variables Anet and Na had positive linear relationships in all treatments. Our results showed that photosynthetic acclimation did not occur in dwarf bamboo at elevated CO₂ and it could adjust physiology and morphology to enable the capture of more light, to increase WUE and improve nutritional conditions. Copyright © Physiologia Plantarum 2012.

  1. Leap frog in slow motion: Divergent responses of tree species and life stages to climatic warming in Great Basin subalpine forests.

    Science.gov (United States)

    Smithers, Brian V; North, Malcolm P; Millar, Constance I; Latimer, Andrew M

    2018-02-01

    In response to climate warming, subalpine treelines are expected to move up in elevation since treelines are generally controlled by growing season temperature. Where treeline is advancing, dispersal differences and early life stage environmental tolerances are likely to affect how species expand their ranges. Species with an establishment advantage will colonize newly available habitat first, potentially excluding species that have slower establishment rates. Using a network of plots across five mountain ranges, we described patterns of upslope elevational range shift for the two dominant Great Basin subalpine species, limber pine and Great Basin bristlecone pine. We found that the Great Basin treeline for these species is expanding upslope with a mean vertical elevation shift of 19.1 m since 1950, which is lower than what we might expect based on temperature increases alone. The largest advances were on limber pine-dominated granitic soils, on west aspects, and at lower latitudes. Bristlecone pine juveniles establishing above treeline share some environmental associations with bristlecone adults. Limber pine above-treeline juveniles, in contrast, are prevalent across environmental conditions and share few environmental associations with limber pine adults. Strikingly, limber pine is establishing above treeline throughout the region without regard to site characteristic such as soil type, slope, aspect, or soil texture. Although limber pine is often rare at treeline where it coexists with bristlecone pine, limber pine juveniles dominate above treeline even on calcareous soils that are core bristlecone pine habitat. Limber pine is successfully "leap-frogging" over bristlecone pine, probably because of its strong dispersal advantage and broader tolerances for establishment. This early-stage dominance indicates the potential for the species composition of treeline to change in response to climate change. More broadly, it shows how species differences in dispersal

  2. Combustion influences on natural abundance nitrogen isotope ratio in soil and plants following a wildfire in a sub-alpine ecosystem.

    Science.gov (United States)

    Huber, Edith; Bell, Tina L; Adams, Mark A

    2013-11-01

    This before-and-after-impact study uses the natural abundance N isotope ratio (δ(15)N) to investigate the effects of a wildfire on sub-alpine ecosystem properties and processes. We measured the (15)N signatures of soil, charred organic material, ash and foliage in three sub-alpine plant communities (grassland, heathland and woodland) in south-eastern Australia. Surface bulk soil was temporarily enriched in (15)N immediately after wildfire compared to charred organic material and ash in all plant communities. We associated the enrichment of bulk soil with fractionation of N during combustion and volatilization of N, a process that also explains the sequential enrichment of (15)N of unburnt leaves > ash > charred organic material in relation to duration and intensity of heating. The rapid decline in (15)N of bulk soil to pre-fire values indicates that depleted ash, containing considerable amounts of total N, was readily incorporated into the soil. Foliar δ(15)N also increased with values peaking 1 year post-fire. Foliar enrichment was foremost coupled with the release of enriched NH4(+) into the soil owing to isotopic discrimination during volatilization of soluble N and combustion of organic material. The mode of post-fire regeneration influenced foliar (15)N enrichment in two species indicating use of different sources of N following fire. The use of natural abundance of (15)N in soil, ash and foliage as a means of tracing transformation of N during wildfire has established the importance of combustion products as an important, albeit temporary source of inorganic N for plants regenerating after wildfire.

  3. [Contribution of soil fauna to the mass loss of Betula albosinensis leaf litter at early decomposition stage of subalpine forest litter in western Sichuan].

    Science.gov (United States)

    Xia, Lei; Wu, Fu-Zhong; Yang, Wan-Qin; Tan, Bo

    2012-02-01

    In order to quantify the contribution of soil fauna to the decomposition of birch (Betula albosinensis) leaf litter in subalpine forests in western Sichuan of Southwest China during freeze-thaw season, a field experiment with different mesh sizes (0.02, 0.125, 1 and 3 mm) of litterbags was conducted in a representative birch-fir (Abies faxoniana) forest to investigate the mass loss rate of the birch leaf litter from 26 October, 2010 to 18 April, 2011, and the contributions of micro-, meso- and macro-fauna to the decomposition of the leaf litter. Over the freeze-thaw season, 11.8%, 13.2%, 15.4% and 19.5% of the mass loss were detected in the litterbags with 0.02, 0. 125, 1 and 3 mm mesh sizes, respectively. The total contribution of soil fauna to the litter decomposition accounted for 39.5% of the mass loss, and the taxa and individual relative density of the soil fauna in the litterbags had the similar variation trend with that of the mass loss rate. The contribution rate of soil fauna to the leaf litter mass loss showed the order of micro- fauna, with the highest contribution of micro-fauna (7.9%), meso-fauna (11.9%), and macro-fauna (22.7%) at the onset of freezing stage, deeply frozen stage, and thawing stage, respectively. The results demonstrated that soil fauna played an important role in the litter decomposition in subalpine forests of western Sichuan during freeze-thaw season.

  4. Using stable water isotopes and borehole NMR to inform an ecohydrological model in a subalpine and upper montane catchment in the Rocky Mountains

    Science.gov (United States)

    Millar, D.; Parsekian, A.; Mercer, J.; Speckman, H. N.; Beverly, D.; Ewers, B. E.; Mackay, D. S.

    2016-12-01

    Recent work using stable water isotopes has revealed that vegetation across a range of different biomes preferentially take up tightly bound soil water over more mobile pools. This so called two water worlds hypothesis (TWWH) has important implications for hydrological modeling efforts in ecosystems where it holds true, since few if any ecohydrological models incorporate this phenomenon. Further, in ecosystems where the TWWH is supported, information regarding the proportion of soil water in the bound and mobile pools is necessary to inform plant-soil water dynamics in models. In this study, we investigate which soil water pools are used by dominant vegetation in an upper montane and subalpine catchment in the Rocky Mountains of southern Wyoming, and use this information to inform the Terrestrial Regional Ecosystem Exchange Simulator (TREES). Within each catchment, we test the TWWH using stable water isotope analyses in an upland coniferous forest and an adjacent, downgradient groundwater-supported wetland. The proportion of soil water in each pool within each ecosystem was inferred from borehole nuclear magnetic resonance (NMR). These field data are being incorporated into TREES, by partitioning plant water uptake between bound and mobile pools. NMR analyses were conducted in all four ecosystems down to a depth of approximately 75 cm and revealed that while mid growing season soil water content was approximately two-fold higher in the subalpine forest versus that of the upper montane forest, the vast majority of soil water, 86% on average, existed in the bound pool in both ecosystems. Alternatively, soils in both wetlands were saturated throughout their profiles, with a majority of the soil water existing in the mobile pool, 63% on average. These initial findings highlight the importance of bound soil water pools in both upland forests, as opposed to the wetlands, which had an abundance of water in both pools.

  5. Seasonal dynamics of the plant community and soil seed bank along a successional gradient in a subalpine meadow on the Tibetan Plateau.

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    Miaojun Ma

    Full Text Available BACKGROUND: Knowledge about how change the importance of soil seed bank and relationship between seed mass and abundance during vegetation succession is crucial for understanding vegetation dynamics. Many studies have been conducted, but their ecological mechanisms of community assembly are not fully understood. METHODOLOGY: We examined the seasonal dynamics of the vegetation and soil seed bank as well as seed size distribution along a successional gradient. We also explored the potential role of the soil seed bank in plant community regeneration, the relationship between seed mass and species abundance, and the relative importance of deterministic and stochastic processes along a successional gradient. PRINCIPAL FINDINGS: Species richness of seed bank increased (shallow layer and the total and seed density decreased (each layer and the total significantly with succession. Species richness and seed density differed significantly between different seasons and among soil depths. Seed mass showed a significant negative relationship with relative abundance in the earliest successional stage, but the relationships were not significant in later stages. Seed mass showed no relationship with relative abundance in the whole successional series in seed bank. Results were similar for both July 2005 and April 2006. CONCLUSIONS: The seed mass and abundance relationship was determined by a complex interaction between small and larger seeded species and environmental factors. Both stochastic processes and deterministic processes were important determinants of the structure of the earliest stage. The importance of seed bank decreased with succession. The restoration of abandoned farmed and grazed meadows to the species-rich subalpine meadow in Tibetan Plateau can be successfully achieved from the soil seed bank. However, at least 20 years are required to fully restore an abandoned agricultural meadow to a natural mature subalpine meadow.

  6. A multi-proxy record of hydroclimate, vegetation, fire, and post-settlement impacts for a subalpine plateau, Central Rocky Mountains U.S.A

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    Anderson, Lesleigh; Brunelle, Andrea; Thompson, Robert S.

    2015-01-01

    Apparent changes in vegetation distribution, fire, and other disturbance regimes throughout western North America have prompted investigations of the relative importance of human activities and climate change as potential causal mechanisms. Assessing the effects of Euro-American settlement is difficult because climate changes occur on multi-decadal to centennial time scales and require longer time perspectives than historic observations can provide. Here, we report vegetation and environmental changes over the past ~13,000 years as recorded in a sediment record from Bison Lake, a subalpine lake on a high plateau in northwestern Colorado. Results are based on multiple independent proxies, which include pollen, charcoal, and elemental geochemistry, and are compared with previously reported interpretations of hydroclimatic changes from oxygen isotope ratios. The pollen data indicate a slowly changing vegetation sequence from sagebrush steppe during the late glacial to coniferous forest through the late Holocene. The most dramatic vegetation changes of the Holocene occurred during the ‘Medieval Climate Anomaly’ (MCA) and ‘Little Ice Age’ (LIA) with rapid replacement of conifer forest by grassland followed by an equally rapid return to conifer forest. Late Holocene vegetation responses are mirrored by changes in fire, lake biological productivity, and watershed erosion. These combined records indicate that subsequent disturbance related to Euro-American settlement, although perhaps significant, had acted upon a landscape that was already responding to MCA-LIA hydroclimatic change. Results document both rapid and long-term subalpine grassland ecosystem dynamics driven by agents of change that can be anticipated in the future and simulated by ecosystem models.

  7. Mercury bioaccumulation in fishes from subalpine lakes of the Wallowa-Whitman National Forest, northeastern Oregon and western Idaho

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    Eagles-Smith, Collin A.; Herring, Garth; Johnson, Branden L.; Graw, Rick

    2013-01-01

    Mercury (Hg) is a globally distributed pollutant that poses considerable risks to human and wildlife health. Over the past 150 years since the advent of the industrial revolution, approximately 80 percent of global emissions have come from anthropogenic sources, largely fossil fuel combustion. As a result, atmospheric deposition of Hg has increased by up to 4-fold above pre-industrial times. Because of their isolation, remote high-elevation lakes represent unique environments for evaluating the bioaccumulation of atmospherically deposited Hg through freshwater food webs, as well as for evaluating the relative importance of Hg loading versus landscape influences on Hg bioaccumulation. The increase in Hg deposition to these systems over the past century, coupled with their limited exposure to direct anthropogenic disturbance make them useful indicators for estimating how changes in Hg emissions may propagate to changes in Hg bioaccumulation and ecological risk. In this study, we evaluated Hg concentrations in fishes of high-elevation, sub-alpine lakes in the Wallowa-Whitman National Forest in northeastern Oregon and western Idaho. Our goals were to (1) assess the magnitude of Hg contamination in small-catchment lakes to evaluate the risk of atmospheric Hg to human and wildlife health, (2) quantify the spatial variability in fish Hg concentrations, and (3) determine the ecological, limnological, and landscape factors that are best correlated with fish total mercury (THg) concentrations in these systems. Across the 28 study lakes, mean THg concentrations of resident salmonid fishes varied as much as 18-fold among lakes. Importantly, our top statistical model explained 87 percent of the variability in fish THg concentrations among lakes with four key landscape and limnological variables— catchment conifer density (basal area of conifers within a lake’s catchment), lake surface area, aqueous dissolved sulfate, and dissolved organic carbon. The basal area of conifers

  8. Characterizing water, energy and CO2 exchange for a Sky Island subalpine forest in the southwestern USA

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    Brown-Mitic, C. M.; Shuttleworth, J.; Harlow, C.; Bales, R.

    2003-04-01

    Among the ecosystems present in the semi-arid environment of the Southwestern U.S., Sky Island forest is unique and it has a unique relationship to the sparse surface-water resources available in the region. This ecosystem exists only at the top of mountains because it is only here that, as a long-term average, precipitation input exceeds evapotranspiration to the extent that forest vegetation can survive. Sky Island Forests, therefore, command potentially significant source areas for the water (some originally falling as snow) that ultimately leaves topographically high ground to recharge aquifers in the plains below by mountain-front recharge. They are also very recently recognized as important carbon sinks where very little or no understanding exist of the exchange/cycling dynamics. The Mount Bigelow project provides an empirically based understanding of the hydro- micrometeorological dynamics of a sky island sub-alpine forest in the southwestern U.S. It is the first study to attempt to document, understand, and model the water, energy, and (related) carbon exchanges of the uniquely interesting and, from the water resource standpoint, uniquely important Sky Island forest ecosystem. The fundamental science issues addressed are: the characteristics of the surface-atmosphere exchanges of water, energy and carbon; the storage of moisture and energy in plants and soil; partitioning of winter snow and rain between evapotranspiration/sublimation, deep drainage and the near-surface environmental water resource that sustains the forest. In order to achieve our objective, a network of four below canopy hydro-micrometeorological stations 10 m tall, and one above canopy 30 m tall high resolution eddy correlation tower, were deployed within a predominantly douglas fir/pine second growth forest. Our observations indicate that the surface flux potential (i.e. sensible heat flux (H) potential), defined as the surface-air temperature gradient varies significantly over space as

  9. Les Gorges de Trévans dans le front subalpin – Un site exceptionnel des Alpes de Haute-Provence

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    Jean Nicod

    2011-10-01

    Full Text Available Les canyons de Trévans sont incisés dans des unités calcaires jurassiques, dans la zone frontale subalpine, proche du piémont de Valensole. Ces reliefs sont en rapport avec les phases néotectoniques. Ce secteur fait principalement partie de la forêt domaniale du Montdenier, avec des écosystèmes montagnards et supra-méditerranéens, bois de hêtres et de chênes pubescents, large extension des brousses et d'importants reboisements en pins noirs. Les hautes surfaces conservent des traces d'un ancien aplanissement et des sols résiduels paléokarstiques. Sur les pentes, sous des escarpements démembrés, les éboulis et convois de blocs témoignent des processus périglaciaires hérités et, localement, des évènements séismiques. De nombreux processus dynamiques s'observent dans les canyons : éboulements provenant des parois affectées des effets de détente, coups de gouge et marmites de géant dans leur fond excavé par les écoulements turbulents dans les cascades… et le Pont de Tuf.The canyon system of Trevans has cut the blocks of the jurassic limestones, in subalpine over thrust front, near the Valensole piedmont. These landforms are in relationship with the neotectonic movements. This area belongs to the State Forest of Montdenier, woodland of various mountain and supra-mediterranean ecosystems, with beeches and white oaks Quercus pubescens, large extent of bush and important reforestation in black pines (Pinus nigra. The high surfaces preserve some relics of the old planation and paleokarstic forms and residual soils. On the slopes, under the break-up escarpments, the screes and landslides give the part of the periglacial processes and, locally, of the seismic events. Numerous dynamic processes occur in the canyons: rock-slides, in relationship with open fractures, scallops and pot-holes in the bottom excavated by the turbulent flows in the waterfalls of the creeks and, only case, a travertine bridge.

  10. Hydrology of the North Klondike River: carbon export, water balance and inter-annual climate influences within a sub-alpine permafrost catchment.

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    Lapp, Anthony; Clark, Ian; Macumber, Andrew; Patterson, Tim

    2017-10-01

    Arctic and sub-arctic watersheds are undergoing significant changes due to recent climate warming and degrading permafrost, engendering enhanced monitoring of arctic rivers. Smaller catchments provide understanding of discharge, solute flux and groundwater recharge at the process level that contributes to an understanding of how larger arctic watersheds are responding to climate change. The North Klondike River, located in west central Yukon, is a sub-alpine permafrost catchment, which maintains an active hydrological monitoring station with a record of >40 years. In addition to being able to monitor intra-annual variability, this data set allows for more complex analysis of streamflow records. Streamflow data, geochemistry and stable isotope data for 2014 show a groundwater-dominated system, predominantly recharged during periods of snowmelt. Radiocarbon is shown to be a valuable tracer of soil zone recharge processes and carbon sources. Winter groundwater baseflow contributes 20 % of total annual discharge, and accounts for up to 50 % of total river discharge during the spring and summer months. Although total stream discharge remains unchanged, mean annual groundwater baseflow has increased over the 40-year monitoring period. Wavelet analysis reveals a catchment that responds to El Niño and longer solar cycles, as well as climatic shifts such as the Pacific Decadal Oscillation. Dedicated to Professor Peter Fritz on the occasion of his 80th birthday.

  11. Dynamics of development and variability of surface degradation in the subalpine and alpine zones (an example from the Velká Fatra Mts., Slovakia

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    Lepeška Tomáš

    2016-01-01

    Full Text Available In the last five centuries, the inappropriate management of the Vel’ká Fatra Mts. sub-alpine and alpine areas has led to the development of different forms of surface destruction. For evaluation of the dynamics and variability of surface degradation the territory of the Hornojelenská valley was chosen. It is a significant avalanche area. It has clearly been destroyed by avalanches, water erosion and cryogenic erosion as well as anthropo-zoogenic processes. The forms of destruction were mapped on a scale of 1:200 based on the aerial photographs and satellite images taken in 1961, 2003, 2009 and 2012. The total area of degradative morphogenetic forms (DMF in 1961 was 5.5780 ha, 4.0650 ha in 2003, 4.5752 ha in 2009 and 4.9431 ha in 2012. The DMF reached its peak in 1961. In the mid-1960s, there were ambitions to reforest the highest areas of the study area that led to the decrease of DMF and the development of vegetation. The present exogenous geomorphologic processes are causing a gradual increase of the total destructed area.

  12. Sensitivity of subalpine tree seedlings and alpine plants to natural and manipulated climate variation: Initial results from an Alpine Treeline Warming Experiment (Invited)

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    Kueppers, L. M.

    2010-12-01

    Niche models and paleoecological studies indicate that future climate change will alter the geographic distributions of plant species. Changes in temperature, snowmelt timing, or moisture conditions at one edge of a species’ range may have different consequences for recruitment, carbon exchange, phenology, and survival than changes at another edge. Similarly, local genetic adaptation may constrain species and community responses to climate change. We have established a new experiment to investigate potential shifts in the distribution of subalpine tree species, and the alpine species they might replace. We are asking how tree species recruitment and alpine species growth and reproduction vary within their current ranges, and in response to temperature and soil moisture manipulations. We are also examining whether genetic provenance and ecosystem processes constrain tree seedling and alpine herb responses. Our Alpine Treeline Warming Experiment is located across three sites at Niwot Ridge, CO, ranging from near the lower limit of subalpine forest to alpine tundra. We use infrared heaters to raise growing season surface soil temperatures by 4-5°C, and to lengthen the growing season. The warming treatment is crossed with a soil moisture manipulation to distinguish effects due to higher temperatures from those due to drier soil. Each plot is a common garden sown with high and low elevation provenances of limber pine (Pinus flexilis) and Engelmann spruce (Picea engelmannii). We established an additional set of experimental plots to examine treatment effects on alpine species phenology, growth and reproduction. Under ambient conditions in 2009, tree seedling germination rate, lifespan, and first season survival was higher within the species’ current range than in the alpine, and for Engelmann spruce, was higher at the low elevation limit than the high elevation limit. Source population (low vs. high elevation) was a significant factor explaining natural variation in

  13. Process coupling and control over the response of net ecosystem CO2 exchange to climate variability and insect disturbance in subalpine forests of the Western US

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    Monson, R. K.; Moore, D. J.; Trahan, N. A.; Scott-Denton, L.; Burns, S. P.; Hu, J.; Bowling, D. R.

    2011-12-01

    Following ten years of studies in subalpine forest ecosystems of the Western US, we have concluded that the tight coupling between gross primary productivity (GPP) and the autotrophic component of soil respiration (Ra) drives responses of net ecosystem CO2 exchange (NEE) to climate variability and insect disturbance. This insight has been gained through long-term eddy flux observations, manipulative plot experiments, analyses of dynamics in the stable isotope compositions of CO2 and H2O, and chamber gas-exchange measurements. Using past observations from these studies, we deployed model-data assimilation techniques and forecast weather/climate modeling to estimate how the coupling between GPP and Ra is likely to affect future (Year 2100) dynamics in NEE. The amount of winter snow and its melting dynamics in the spring represents the dominant control over interannual variation in GPP. Using the SIPNET ecosystem process model, combined with knowledge about the stable isotope content of different water sources, we estimated that approximately 75% of growing season GPP is coupled to the use of snowmelt water, whereas approximately 25% is coupled to summer rain. The tight coupling between GPP and winter snow pack drives a similar tight coupling between soil respiration (Rs) and winter snow pack. Manipulation of snow pack on forest plots has shown that Rs increases with increased snow pack, and this effect disappears when trees are girdled, which stops the transfer of GPP to roots and the soil rhizosphere. Higher-than-normal winter snowpacks cause the carbon isotope ratios of soil-respired CO2 to be depleted in 13C, reflecting a signal of lower photosynthetic water-use efficiency in the GPP that is transferred to the soil rhizosphere. Large-scale forest disturbance due to catastrophic tree mortality from mountain pine beetle attack causes an initial (2-3 year) reduction in Rs, which is attributable to the loss of GPP and its effect on Ra. This near-term reduction in Rs

  14. Transplantation of subalpine wood-pasture turfs along a natural climatic gradient reveals lower resistance of unwooded pastures to climate change compared to wooded ones.

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    Gavazov, Konstantin; Spiegelberger, Thomas; Buttler, Alexandre

    2014-04-01

    Climate change could impact strongly on cold-adapted mountain ecosystems, but little is known about its interaction with traditional land-use practices. We used an altitudinal gradient to simulate a year-round warmer and drier climate for semi-natural subalpine grasslands across a landscape of contrasting land-use management. Turf mesocosms from three pasture-woodland land-use types-unwooded pasture, sparsely wooded pasture, and densely wooded pasture-spanning a gradient from high to low management intensity were transplanted downslope to test their resistance to two intensities of climate change. We found strong overall effects of intensive (+4 K) experimental climate change (i.e., warming and reduced precipitation) on plant community structure and function, while moderate (+2 K) climate change did not substantially affect the studied land-use types, thus indicating an ecosystem response threshold to moderate climate perturbation. The individual land-use types were affected differently under the +4 K scenario, with a 60% decrease in aboveground biomass (AGB) in unwooded pasture turfs, a 40% decrease in sparsely wooded pasture turfs, and none in densely wooded ones. Similarly, unwooded pasture turfs experienced a 30% loss of species, advanced (by 30 days) phenological development, and a mid-season senescence due to drought stress, while no such effects were recorded for the other land-use types. The observed contrasting effects of climate change across the pasture-woodland landscape have important implications for future decades. The reduced impact of climate change on wooded pastures as compared to unwooded ones should promote the sustainable land use of wooded pastures by maintaining low management intensity and a sparse forest canopy, which buffer the immediate impacts of climate change on herbaceous vegetation.

  15. Temporal dynamics of abiotic and biotic factors on leaf litter of three plant species in relation to decomposition rate along a subalpine elevation gradient.

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    Jianxiao Zhu

    Full Text Available Relationships between abiotic (soil temperature and number of freeze-thaw cycles or biotic factors (chemical elements, microbial biomass, extracellular enzymes, and decomposer communities in litter and litter decomposition rates were investigated over two years in subalpine forests close to the Qinghai-Tibet Plateau in China. Litterbags with senescent birch, fir, and spruce leaves were placed on the forest floor at 2,704 m, 3,023 m, 3,298 m, and 3,582 m elevation. Results showed that the decomposition rate positively correlated with soil mean temperature during the plant growing season, and with the number of soil freeze-thaw cycles during the winter. Concentrations of soluble nitrogen (N, phosphorus (P and potassium (K had positive effects but C:N and lignin:N ratios had negative effects on the decomposition rate (k, especially during the winter. Meanwhile, microbial biomass carbon (MBC, N (MBN, and P (MBP were positively correlated with k values during the first growing season. These biotic factors accounted for 60.0% and 56.4% of the variation in decomposition rate during the winter and the growing season in the first year, respectively. Specifically, litter chemistry (C, N, P, K, lignin, C:N and lignin:N ratio independently explained 29.6% and 13.3%, and the microbe-related factors (MBC, MBN, MBP, bacterial and fungal biomass, sucrase and ACP activity explained 22.9% and 34.9% during the first winter and the first growing season, respectively. We conclude that frequent freeze-thaw cycles and litter chemical properties determine the winter decomposition while microbe-related factors play more important roles in determining decomposition in the subsequent growing season.

  16. Exploring the landscape evolution of the subalpine meadow-forest system driven by the geomorphic work performed by the Northern Pocket Gopher

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    Winchell, E. W.; Anderson, R. S.; Lombardi, E. M.; Doak, D. F.

    2015-12-01

    In the subalpine zone of the Colorado Front Range, field observations suggest that the Northern Pocket Gopher acts as a significant geomorphic agent within meadows, but not within forests. Field surveys during 2014 and 2015 demonstrate that the temporal and spatial digging patterns of gopher-excavated mounds and infilled tunnels are neither steady nor uniform. These include 1) gophers spend the winter near the forest-meadow (FM) edge and the remainder of the year within the meadow, and 2) surface mound generation greatly accelerates in late summer. Hourly subsurface temperatures across the FM pair, and daily digital snow depths at the FM boundary suggest that gophers spend the winter beneath thick snow cover where ground temperatures are warmest. LiDAR-based topography demonstrates that slopes are uniform across the FM pairs, diverging from that expected by extrapolation of the observed pattern of non-uniform geomorphic activity. The topography therefore suggests that the FM boundaries are not stationary. We hypothesize that the landscape is more uniformly impacted by gopher activity in the long term, which requires that 1) FM boundaries migrate significantly and/or 2) meadows are born in different places following forest death via fire followed by rapid gopher habitation. The vertical geomorphic signature of gopher activity is more distinct. Preliminary probing of meadows reveals a 20 cm thick biomantle with a high concentration of stones at ~20 cm depth. The annual surface areas of mounds and infilled tunnels suggest that the entire meadow can be exposed to excavated tillings on century timescales. Further, annual mound volumes suggest that the biomantle is turned over also on century timescales. We will report results of stone line surveys and 137Cs concentration profiles within the forest and meadow that will test the long-term stability of meadows and the timescale over which vertical churning mixes the near-surface material within this landscape.

  17. Use of cosmogenic 35S for comparing ages of water from three alpine-subalpine basins in the Colorado Front Range

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    Sueker, J.K.; Turk, J.T.; Michel, R.L.

    1999-01-01

    High-elevation basins in Colorado are a major source of water for the central and western United States; however, acidic deposition may affect the quality of this water. Water that is retained in a basin for a longer period of time may be less impacted by acidic deposition. Sulfur-35 (35S), a short-lived isotope of sulfur (t( 1/2 ) = 87 days), is useful for studying short-time scale hydrologic processes in basins where biological influences and water/rock interactions are minimal. When sulfate response in a basin is conservative, the age of water may be assumed to be that of the dissolved sulfate in it. Three alpine-subalpine basins on granitic terrain in Colorado were investigated to determine the influence of basin morphology on the residence time of water in the basins. Fern and Spruce Creek basins are glaciated and accumulate deep snowpacks during the winter. These basins have hydrologic and chemical characteristics typical of systems with rapid hydrologic response times. The age of sulfate leaving these basins, determined from the activity of 35S, averages around 200 days. In contrast, Boulder Brook basin has broad, gentle slopes and an extensive cover of surficial debris. Its area above treeline, about one-half of the basin, is blown free of snow during the winter. Variations in flow and solute concentrations in Boulder Brook are quite small compared to Fern and Spruce Creeks. After peak snowmelt, sulfate in Boulder Brook is about 200 days older than sulfate in Fern and Spruce Creeks. This indicates a substantial source of older sulfate (lacking 35S) that is probably provided from water stored in pore spaces of surficial debris in Boulder Brook basin.

  18. Effects of a long-term disturbance on arthropods and vegetation in subalpine wetlands: manifestations of pack stock grazing in early versus mid-season.

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    Jeffrey G Holmquist

    Full Text Available Conclusions regarding disturbance effects in high elevation or high latitude ecosystems based solely on infrequent, long-term sampling may be misleading, because the long winters may erase severe, short-term impacts at the height of the abbreviated growing season. We separated a long-term effects of pack stock grazing, manifested in early season prior to stock arrival, from b additional pack stock grazing effects that might become apparent during annual stock grazing, by use of paired grazed and control wet meadows that we sampled at the beginning and end of subalpine growing seasons. Control meadows had been closed to grazing for at least two decades, and meadow pairs were distributed across Sequoia National Park, California, USA. The study was thus effectively a landscape-scale, long-term manipulation of wetland grazing. We sampled arthropods at these remote sites and collected data on associated vegetation structure. Litter cover and depth, percent bare ground, and soil strength had negative responses to grazing. In contrast, fauna showed little response to grazing, and there were overall negative effects for only three arthropod families. Mid-season and long-term results were generally congruent, and the only indications of lower faunal diversity on mid-season grazed wetlands were trends of lower abundance across morphospecies and lower diversity for canopy fauna across assemblage metrics. Treatment x Season interactions almost absent. Thus impacts on vegetation structure only minimally cascaded into the arthropod assemblage and were not greatly intensified during the annual growing season. Differences between years, which were likely a response to divergent snowfall patterns, were more important than differences between early and mid-season. Reliance on either vegetation or faunal metrics exclusively would have yielded different conclusions; using both flora and fauna served to provide a more integrative view of ecosystem response.

  19. Effects of a long-term disturbance on arthropods and vegetation in subalpine wetlands: manifestations of pack stock grazing in early versus mid-season.

    Science.gov (United States)

    Holmquist, Jeffrey G; Schmidt-Gengenbach, Jutta; Haultain, Sylvia A

    2013-01-01

    Conclusions regarding disturbance effects in high elevation or high latitude ecosystems based solely on infrequent, long-term sampling may be misleading, because the long winters may erase severe, short-term impacts at the height of the abbreviated growing season. We separated a) long-term effects of pack stock grazing, manifested in early season prior to stock arrival, from b) additional pack stock grazing effects that might become apparent during annual stock grazing, by use of paired grazed and control wet meadows that we sampled at the beginning and end of subalpine growing seasons. Control meadows had been closed to grazing for at least two decades, and meadow pairs were distributed across Sequoia National Park, California, USA. The study was thus effectively a landscape-scale, long-term manipulation of wetland grazing. We sampled arthropods at these remote sites and collected data on associated vegetation structure. Litter cover and depth, percent bare ground, and soil strength had negative responses to grazing. In contrast, fauna showed little response to grazing, and there were overall negative effects for only three arthropod families. Mid-season and long-term results were generally congruent, and the only indications of lower faunal diversity on mid-season grazed wetlands were trends of lower abundance across morphospecies and lower diversity for canopy fauna across assemblage metrics. Treatment x Season interactions almost absent. Thus impacts on vegetation structure only minimally cascaded into the arthropod assemblage and were not greatly intensified during the annual growing season. Differences between years, which were likely a response to divergent snowfall patterns, were more important than differences between early and mid-season. Reliance on either vegetation or faunal metrics exclusively would have yielded different conclusions; using both flora and fauna served to provide a more integrative view of ecosystem response.

  20. Lake biota response to human impact and local climate during the last 200 years: A multi-proxy study of a subalpine lake (Tatra Mountains, W Carpathians).

    Science.gov (United States)

    Hamerlík, Ladislav; Dobríková, Daniela; Szarlowicz, Katarzyna; Reczynski, Witold; Kubica, Barbara; Šporka, Ferdinand; Bitušík, Peter

    2016-03-01

    Element content, loss-on-ignition, chironomid analysis and (210)Pb dating were applied on a sediment core from a subalpine Tatra lake (Popradské pleso) to reveal the response of aquatic biota to eutrophication induced by human activities in the lake catchment. The lead dating indicates that the 0-8 cm section of the core represents the past ca 200 years, ending at ~1814 AD. Comparing the key changes of the proxies with human activities that are historically well documented, four phases of the recent lake development were distinguished: (1) a pre-tourism phase, (2) a phase of increasing touristic activity and early cottage development, (3) a phase of eutrophication, and (4) a phase of post-eutrophication. Neither touristic activity, nor early cottage development around the lake (1st and 2nd phases) had considerable influence on the chironomid assemblage structure or organic content of the lake. The most significant change both in chironomid assemblage structure and loss-on-ignition occurred during the 3rd phase, when a big tourist hotel was built close by the lake and started contaminating it via direct wastewater input. However, the structure of the chironomid assemblage has not changed significantly over time and the dominating taxa remained the same during the whole period. Parallel with the nutrient signal of the paleo assemblage, a secondary signal has been identified as the ratio of rheophilic taxa on total abundance that did not correlate with the sediment's organic content, and is most likely driven by local climatic oscillations. Changes of most of metal elements concentrations reflected rather bigger scale changes of industrial activities than local scale human disturbances. Our results indicate that hydromorphological properties can moderate the impact of organic pollution on the lake biota. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Comparisons of photosynthesis-related traits of 27 abundant or subordinate bryophyte species in a subalpine old-growth fir forest.

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    Wang, Zhe; Bader, Maaike Y; Liu, Xin; Zhu, Zhangming; Bao, Weikai

    2017-09-01

    Bryophyte communities can exhibit similar structural and taxonomic diversity as vascular plant communities, just at a smaller scale. Whether the physiological diversity can be similarly diverse, and whether it can explain local abundance patterns is unknown, due to a lack of community-wide studies of physiological traits. This study re-analyzed data on photosynthesis-related traits (including the nitrogen, phosphorus and chlorophyll concentrations, photosynthetic capacities, and photosynthetic nutrient use efficiencies) of 27 bryophyte species in a subalpine old-growth fir forest on the eastern Tibetan Plateau. We explored differences between taxonomic groups and hypothesized that the most abundant bryophyte species had physiological advantages relative to other subdominant species. Principal component analysis (PCA) was used to summarize the differences among species and trait values of the most abundant and other co-occurring subdominant species. Species from the Polytrichaceae were separated out on both PCA axes, indicating their high chlorophyll concentrations and photosynthetic capacities (axis 1) and relatively high-light requirements (axis 2). Mniaceae species also had relatively high photosynthetic capacities, but their light saturation points were low. In contrast, Racomitrium joseph-hookeri and Lepidozia reptans , two species with a high shoot mass per area, had high-light requirements and low nutrient and chlorophyll concentrations and photosynthetic capacities. The nutrient concentrations, photosynthetic capacities, and photosynthetic nutrient use efficiencies of the most abundant bryophyte species did not differ from co-occurring subdominant species. Our research confirms the links between the photosynthesis-related traits and adaptation strategies of bryophytes. However, species relative abundance was not related to these traits.

  2. Condição corporal e desempenho produtivo de cabras Alpinas no início de lactação Body condition and productive performance of Alpine goat in early lactation

    Directory of Open Access Journals (Sweden)

    Larissa Pires Barbosa

    2009-11-01

    Full Text Available Objetivou-se avaliar a influência da condição corporal ao parto sobre os parâmetros produtivos de cabras Alpinas no início da lactação. Sessenta e oito cabras foram distribuídas em três grupos, de acordo com o escore de condição corporal (baixo, entre 1,00 e 2,75; intermediário, entre 2,75 e 3,50; e alto, entre 3,50 e 5,00 e avaliadas do parto até a oitava semana de lactação. Realizaram-se o controle diário do consumo alimentar e da produção leiteira e avaliações semanais de peso corporal, escore da condição corporal e composição do leite. Os animais com escore corporal alto apresentaram menor consumo de matéria seca, fibra em detergente neutro e proteína bruta em comparação àqueles com escores corporais baixo e intermediário. O período médio de recuperação do consumo de matéria seca dos animais das três condições corporais foi de 16 dias (2,3 semanas do pós-parto, com estabilização até o final do experimento. Na sexta semana de lactação, o peso corporal dos animais com escore corporal baixo se igualou ao daqueles com escore corporal intermediário. Não houve efeito da condição corporal ao parto nas variações de ECC e da produção leiteira ao longo do período. O teor de gordura do leite dos animais com escore corporal alto foi menor nas duas primeiras semanas pós-parto em comparação ao dos animais com escores corporais baixo e intermediário. Elevada condição corporal ao parto influencia negativamente o consumo voluntário de cabras leiteiras no início da lactação, mas quando se utiliza dieta de alta qualidade e com altos níveis de energia, a influência da condição corporal ao parto inexiste para variações de peso, de escore da condição corporal e produção leiteira dos animais.The objective of this study was to evaluate the influence of body condition at birth on Alpine goat productive parameters in early lactation. Sixty-eight females were assigned to three groups according to

  3. The influence of warm-season precipitation on the diel cycle of the surface energy balance and carbon dioxide at a Colorado subalpine forest site

    Science.gov (United States)

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

    2015-12-01

    Precipitation changes the physical and biological characteristics of an ecosystem. Using a precipitation-based conditional sampling technique and a 14 year data set from a 25 m micrometeorological tower in a high-elevation subalpine forest, we examined how warm-season precipitation affected the above-canopy diel cycle of wind and turbulence, net radiation Rnet, ecosystem eddy covariance fluxes (sensible heat H, latent heat LE, and CO2 net ecosystem exchange NEE) and vertical profiles of scalars (air temperature Ta, specific humidity q, and CO2 dry mole fraction χc). This analysis allowed us to examine how precipitation modified these variables from hourly (i.e., the diel cycle) to multi-day time-scales (i.e., typical of a weather-system frontal passage). During mid-day we found the following: (i) even though precipitation caused mean changes on the order of 50-70 % to Rnet, H, and LE, the surface energy balance (SEB) was relatively insensitive to precipitation with mid-day closure values ranging between 90 and 110 %, and (ii) compared to a typical dry day, a day following a rainy day was characterized by increased ecosystem uptake of CO2 (NEE increased by ≈ 10 %), enhanced evaporative cooling (mid-day LE increased by ≈ 30 W m-2), and a smaller amount of sensible heat transfer (mid-day H decreased by ≈ 70 W m-2). Based on the mean diel cycle, the evaporative contribution to total evapotranspiration was, on average, around 6 % in dry conditions and between 15 and 25 % in partially wet conditions. Furthermore, increased LE lasted at least 18 h following a rain event. At night, even though precipitation (and accompanying clouds) reduced the magnitude of Rnet, LE increased from ≈ 10 to over 20 W m-2 due to increased evaporation. Any effect of precipitation on the nocturnal SEB closure and NEE was overshadowed by atmospheric phenomena such as horizontal advection and decoupling that create measurement difficulties. Above-canopy mean χc during wet conditions was

  4. The effect of warm-season precipitation on the diel cycle of the surface energy balance and carbon dioxide at a Colorado subalpine forest site

    Science.gov (United States)

    Burns, S. P.; Blanken, P. D.; Turnipseed, A. A.; Monson, R. K.

    2015-06-01

    Precipitation changes the physical and biological characteristics of an ecosystem. Using a precipitation-based conditional sampling technique and a 14 year dataset from a 25 m micrometeorological tower in a high-elevation subalpine forest, we examined how warm-season precipitation affected the above-canopy diel cycle of wind and turbulence, net radiation Rnet, ecosystem eddy covariance fluxes (sensible heat H, latent heat LE, and CO2 net ecosystem exchange NEE) and vertical profiles of scalars (air temperature Ta, specific humidity q, and CO2 dry mole fraction χc). This analysis allowed us to examine how precipitation modified these variables from hourly (i.e., the diel cycle) to multi-day time-scales (i.e., typical of a weather-system frontal passage). During mid-day we found: (i) even though precipitation caused mean changes on the order of 50-70% to Rnet, H, and LE, the surface energy balance (SEB) was relatively insensitive to precipitation with mid-day closure values ranging between 70-80%, and (ii) compared to a typical dry day, a day following a rainy day was characterized by increased ecosystem uptake of CO2 (NEE increased by ≈ 10%), enhanced evaporative cooling (mid-day LE increased by ≈ 30 W m-2), and a smaller amount of sensible heat transfer (mid-day H decreased by ≈ 70 W m-2). Based on the mean diel cycle, the evaporative contribution to total evapotranspiration was, on average, around 6% in dry conditions and 20% in wet conditions. Furthermore, increased LE lasted at least 18 h following a rain event. At night, precipitation (and accompanying clouds) reduced Rnet and increased LE. Any effect of precipitation on the nocturnal SEB closure and NEE was overshadowed by atmospheric phenomena such as horizontal advection and decoupling that create measurement difficulties. Above-canopy mean χc during wet conditions was found to be about 2-3 μmol mol-1 larger than χc on dry days. This difference was fairly constant over the full diel cycle

  5. Consumo de nutrientes, produção e composição do leite de cabras da raça Alpina alimentadas com dietas contendo diferentes teores de fibra Nutrient intake and milk yield and composition of Alpine lactating goats fed diets with different fiber levels

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    Sérgio Carvalho

    2006-06-01

    Full Text Available Foram utilizadas 50 cabras Alpinas em lactação objetivando-se avaliar os efeitos de diferentes teores de fibra em detergente neutro proveniente da forragem (FDNF sobre o consumo de nutrientes, a produção e a composição do leite. Os animais foram confinados em baias individuais e distribuídos aleatoriamente em um delineamento experimental inteiramente casualizado, com cinco tratamentos e dez repetições. Foi utilizada uma ração em mistura completa, composta de feno de tifton-85 (Cynodon sp., fubá de milho, farelo de soja e mistura mineral. As dietas experimentais continham 20, 27, 34, 41 ou 48% de FDNF. Com o aumento da FDNF das dietas, houve redução linear dos consumos de MS, MO, CHT, CNE e energia líquida (EL, além de aumento linear dos consumos de FDN, FDN proveniente da forragem (FDNF e FDA. Não foi observado efeito do teor de FDNF sobre o teor de gordura e de sólidos totais do leite. A produção de leite (corrigida e não corrigida e de sólidos totais diminuiu linearmente. A eficiência de utilização da energia metabolizável consumida para produção de leite atingiu o plateau com uma dieta contendo 35,4% de FDNF.Fifty Alpine lactating does were used to evaluate the effects of feeding different levels of forage neutral detergent fiber (FNDF on nutrient intake and milk yield and composition. Animals were housed individually and assigned to a completely randomized design with five treatments and ten replicates. A total mixed ration, containing Tifton-85 (Cynodon sp. hay, ground corn, soybean meal and mineral mixture was fed ad libitum. The experimental diets contained 20, 27, 34, 41 or 48% of FNDF. As dietary FNDF increased, the intakes of DM, OM, CP, EE, TC, NSC and net energy (NE decreased linearly. In addition, increasing dietary FNDF linearly increased intakes of NDF, FNDF and ADF. There was no effect of FNDF level on contents of milk fat and milk total solids. However, milk yield, fat-corrected milk and yield of

  6. Influência do transporte e mudança de local de manejo nas variáveis fisiológicas e produtivas de cabras Alpinas Physiologic and productive responses of Alpine goats submitted to transportation to a new dairy location

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    T.S. Canaes

    2009-08-01

    Full Text Available Estudaram-se o efeito do transporte e a mudança de local de manejo sobre a produção e a composição do leite e sobre as variáveis fisiológicas, utilizando-se 12 cabras da raça Alpina em final de lactação. Semanalmente, foram mensuradas a produção e composição do leite e a contagem de células somáticas, além do volume do leite residual após administração de ocitocina. Foram colhidas amostras de sangue para dosagem hormonal (cortisol e enzimática (glicose no plasma no dia do transporte: antes (7h10min e após (8h20min, 8h30min e 10h30min o transporte. Nas três semanas subsequentes ao transporte, também foram colhidas amostras de sangue às 8h20min. Obtiveram-se teores mais elevados (PThe effects of transportation and reallocation on milk production and composition and physiological responses were studied in 12 late-lactation Alpine goats. Weekly, somatic cell count, milk production and composition, and residual milk volume (after administration of oxytocin were monitored. Blood samples were taken for hormonal (cortisol and enzymatic dosages (glucose in plasma on the day of transportation: before (7h10min and after transportation (8h20min, 8h30min, and 10h30min. During the three weeks after transportation, blood samples were also taken at 8h20min. Higher levels (P<0.05 of cortisol and glucose after transportation and reallocation were observed and milk yield was significantly lower (P<0.05 one day after them. Milk fat percentage and somatic cell count (P<0.05 were higher after transportation. Results allow concluding that transportation is a stressor agent that may momentarily influence animal production.

  7. Efeitos do estresse térmico sobre a produção, composição química do leite e respostas termorreguladoras de cabras da raça alpina Thermal stress effects on milk yield and chemical composition and thermoregulatory responses of lactating alpines goats

    Directory of Open Access Journals (Sweden)

    Lúcia Helena de Albuquerque Brasil

    2000-12-01

    Full Text Available Seis cabras da raça Alpina, com produção média de leite de 2,5 kg/dia, foram distribuídas aleatoriamente em dois grupos de três e submetidas à termoneutralidade ou estresse térmico por 56 dias em câmara climática. Usou-se um delineamento estatístico "crossover". A temperatura média do ar diurna, incluindo radiação solar simulada, foi de 33,84ºC. Os animais estressados aumentaram a freqüência respiratória, o volume-minuto respiratório, a termólise-evaporativa respiratória, temperatura retal e a taxa de sudorese, enquanto o volume corrente respiratório e o volume globular diminuíram. Houve também perda de peso, redução da ingestão de alimentos e duplicação do consumo de água. A produção de leite e a porcentagem de gordura, proteína, lactose e sólidos totais diminuíram. Os teores de cloretos, cálcio e fósforo não sofreram alteração. Concluiu-se que, para manter a homeotermia, as cabras mobilizaram o sistema respiratório e sudoríparo para perder calor. A alta temperatura ambiente efetiva reduziu a produção e os teores de alguns componentes do leite.Six Alpine goats with an average milk yield of 2.5 kg/day were randomly assigned to two groups of three and allotted to thermoneutral or heat stress conditions, for 56 days in climate chamber room. A crossover experimental design was used. The goats under heat stress were exposed to a diurnal average air temperature plus simulated solar radiation of 33. 84ºC. The heat-stressed goats showed elevated respiratory frequency, respiratory minute volume, respiratory evaporation, rectal temperature and sweating rate, while the tidal volume and packed cell volume decreased. Further weight loss, decreased feed intake, and their water consumption doubled. The milk yield, the percentage of fat, protein, lactose and total solid contents decreased. The contents of chloride, calcium and phosphorus did not change. The goats mobilized the respiratory and sweating systems to

  8. How Evapotranspiration And Deep Percolation Impact The Precipitation-Runoff Response, Aquifer Recharge, And Linked Nutrient-Water Cycling At The Subalpine Como Creek Drainage In The Colorado Front Range

    Science.gov (United States)

    Zeliff, M. M.; Williams, M. W.; Cowie, R. M.; Burns, S.

    2011-12-01

    Here we evaluate how evapotranspiration (ET) and deep percolation (DP) impact the precipitation-runoff response, aquifer recharge, and linked nutrient-water cycling at the 664-ha sub-alpine Como Creek drainage in the Colorado Front Range. ET is measured continuously using eddy covariance, soil moisture (SM) is measured using 2-m vertical sensor arrays, groundwater (GW) by a series of piezometers, and precipitation (P) is measured daily along with snow-water equivalent (SWE). From 2004 to 2009, annual P averaged 813 mm and ET averaged 590 mm, with ET thus representing 72.5% of annual P. Using multiple linear regression analysis, discharge (Q) was found to be modeled reasonably well with the independent variables of ET (p ground water system and subsequent precipitation does little to contribute to streamflow for the current year, but serves to offset ET, which may explain the decrease in Q with increasing P. Newly installed piezometers (12, at depths ranging from 5 to 30 m) provide evidence that this portion of the basin is largely a loosing reach during snowmelt, with GW in the piezometers increasing 5-7 m. After peak snowmelt however, the reach starts gaining again with piezometer levels dropping. Time series plots reveal a strong relationship between SWE and Q with larger SWE often resulting in larger Q. Thus, surface-groundwater interactions are tightly coupled during snowmelt, with snowmelt first replenishing the subsurface water deficit before contributing to discharge. The deepest two piezometers (18 and 29 m) were not showing any significant water level declines by early August 2011, suggesting that water loss to DP is a potential important component of the water balance in the Como Creek catchment. Wet precipitation chemistry from the National Atmospheric Deposition Program monitors in the basin show that atmospheric deposition of inorganic nitrogen has increased several-fold in the last 25 years. However, in contrast to higher-elevation catchments, which

  9. SEXAGEM FETAL PELA ULTRA-SONOGRAFIA IDENTIFICANDO-SE O TUBÉRCULO GENITAL OU A GENITÁLIA EXTERNA DE CAPRINOS DA RAÇA ALPINA AMERICANA FETAL SEXING BY ULTRASONOGRAPHY IDENTIFYING THE GENITAL TUBERCLE OR EXTERNAL GENITALIA OF AMERICAN ALPINE GOATS

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    Jairo Pereira Neves

    2007-07-01

    Full Text Available Neste trabalho objetivou-se diagnosticar precoce¬mente o sexo de fetos caprinos da raça Alpina Americana através da ultra-sonografia, identificando-se a posição final do tubérculo genital (TG ou visualizando-se as estruturas anatômicas da genitália externa, bem como avaliar a acu¬rácia da sexagem fetal resultante de exame único ou repe¬tido. No Grupo I (GI, identificou-se o sexo levando-se em consideração o posicionamento final do TG, e no Grupo II (GII a presença de estruturas anatômicas da genitália externa. Realizaram-se os exames por via transretal com aparelho de ultra-som (240 Parus - Pie Medical equipado com transdutor linear de 6 e 8 MHz. No GI, 52 fetos de 32 matrizes foram monitorados em intervalos de doze horas, do 40º ao 60º dia de gestação. No GII, submeteram-se 34 fetos de 24 matrizes com gestação entre 45 e 70 dias a exame único. A acurácia da sexagem no GI foi de 100% na gestação simples, 87,5% na dupla e 66,7% na tríplice, sen¬do registrada diferença significativa (P < 0,05 entre gesta¬ção simples e tríplice. No GII, a acurácia foi de 85,7% na gestação simples e de 80,0% na dupla, não sendo obser¬vada diferença (P > 0,05 entre ambas. A migração do TG genital ocorreu, em média, no 46,4 ± 2,1 dia de gestação. Os resultados permitem concluir que a ultra-sonografia é um método apropriado para diagnosticar precocemente o sexo fetal através da identificação da posição final do TG ou da visualização de estruturas anatômicas da genitália externa e que exames repetidos não aumentam a acurácia da sexagem fetal na gestação múltipla. PALAVRAS-CHAVES: Bolsa escrotal, prepúcio, tetas, vulva. The aim of this study was to diagnostic previously the gender of American Alpine fetuses by ultrasonography identifying the final position of the genital tubercle (GT or viewing the anatomical structures of external genitalia, as well as to evaluate the accuracy of fetal sexing by single

  10. NEW ASPECTS OF THE ALPINE VEGETATION OF PARÂNG MOUNTAINS (SOUTH CARPATHIANS

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    SIMON TIBOR

    2012-12-01

    Full Text Available 4 plant communities unknown in the the European syntaxonomy are described from the alpine and subalpine belts of Parâng Mountains, based on vegetation studies of the authors during 1955–1960. These are: Arabis alpina-Saxifraga aizoides, Arabis alpina-Delphinium elatum, Dianthus tenuifolius-Festuca dalmatica and the Primula minima-Dryas octopetala communities. These communities could be described later as new associations in the possession of more relevés from different localities. The East and South Carpathian Doronico carpatici-Festucetum pictae association is distinguished under this new name from the Festucetum pictae Krajina described from the Tatra Mountains. 7 further associations are found as new to the Parâng Mountains.

  11. Kentucky bluegrass (Poa pratensis L.) germplasm for non-burn seed production

    Science.gov (United States)

    A ban on open-field burning of post-harvest residue of grass seed production fields has been implemented in Washington, and restrictions are in place in Idaho and Oregon, USA. Our previous research showed that without post-harvest burning of residue, bluegrass seed yield decreased over time (Johnson...

  12. [Population ecology of the mouse Peromyscus mexicanus (Rodentia: Muridae) in Poas Volcano National Park, Costa Rica].

    Science.gov (United States)

    Rojas Rojas, Licidia; Barboza Rodríguez, Minor

    2007-01-01

    The Mexican Deer Mouse has been reported as an abundant wild mouse in Costa Rica; nevertheless, it has not been studied as well as other Peromyscus species. Thirty Sherman traps were placed on three habitats during six consecutive days of each month, from March 2002 through April 2003 in three sites of Pods Volcano National Park, Costa Rica. A total of 2 393 mice were captured. Other species such as Reithrodontomys creper, R. rodriguezi, Scotinomys teguina and Oryzomys devius (Muridae) were also captured in Tierra Fría and R. creper R. sumichrasti, S. teguina and O. devius in Potrero Grande. In Canto de las Aves we captured P. mexicanus, R. creper, R. rodriguezi and O. devius. Of the total mice collected, 34.77% were P. mexicanus. For this species, the mean monthly capture per hectare was 34 +/- 2.15 in Tierra Fría and 11 +/- 1.85 in Potrero Grande. In the third site, Canto de las Aves, only four mice were captured throughout the study. The estimated population size did not change among months in Tierra Fria, but it did in Potrero Grande. No sex ratio variation was found in any habitat. In Potrero Grande, weight averages were 43.54 +/- 3.42 g for males and 42.08 +/- 3.45 g for females. Variation in population structure among habitats was not significant. The presence of oak trees (Quercus sp.) and the high understory density could explain the stability of the population in this area.

  13. Enhanced polyunsaturated fatty acids production in Mortierella alpina by SSF and the enrichment in chicken breasts

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    Shengli Yang

    2016-10-01

    Full Text Available Background: Distiller's dried grains with solubles (DDGS and soybean meal were used as the substrates for the production of polyunsaturated fatty acids (PUFA in solid-state fermentation (SSF by Mortierella alpine. These fermented products were fed to laying hens. PUFA enrichment from chicken breasts was studied. Methods: The maximum productivity of PUFA was achieved under optimized process condition, including 1% w/w yeast extract as additive, an incubation period of 5 days at 12°C, 10% v/w inoculum level, 75% moisture content, and pH 6.0. The hens were then fed with ration containing soybean DDGS, rapeseed oil, soybean oil, and peanut oil. The control group was fed with basal ration. Results: Under the optimal condition, M. alpine produced total fatty acids (TFA of 182.34 mg/g dry substrate. It has better mycelial growth when soybean meal was added to DDGS (SDDGS. PUFA in fermentation product increased with higher soybean meal content. The addition of 70% soybean meal to DDGS substrate yielded 175.16 mg of TFA, including 2.49 mg eicosapentaenoic acid (EPA and 5.26 mg docosahexaenoic acid (DHA. The ratios of ω-6/ω-3 found in chicken breasts fat were all lower than that found in control by 36.98, 31.51, 18.15, and 12.63% for SDDGS, rapeseed oil, soybean oil, and peanut oil, respectively. Conclusions: This study identified an optimized SSF process to maximize PUFA productivity by M. alpine as the strain. This PUFA-enriched feed increased the PUFA contents as well as the proportions of ω-6 and ω-3 in chicken breasts and liver.

  14. Hydrology and landscape structure control subalpine catchment carbon export

    Science.gov (United States)

    Vincent Jerald Pacific

    2009-01-01

    Carbon export from high elevation ecosystems is a critical component of the global carbon cycle. Ecosystems in northern latitudes have become the focus of much research due to their potential as large sinks of carbon in the atmosphere. However, there exists limited understanding of the controls of carbon export from complex mountain catchments due to strong spatial and...

  15. L'aménagement piscicole des lacs subalpins

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    VIVIER P.

    1964-04-01

    Le rendement financier annuel varie non seulement avec l'abondance des captures mais aussi avec la qualité du poisson péché. Aussi dans le Lac Léman le prix moyen de 10 kg de poisson péchés a augmenté de 4 F, de 1922 à 1961, grâce à une plus grande abondance relative des Corégones.

  16. Studies on the zooplankton of the deep subalpine Lake Garda.

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    Luigi NASELLI-FLORES

    1999-02-01

    Full Text Available The specific composition and seasonal dynamics of the zooplankton of Lake Garda have been studied through monthly surveys in two annual cycles (December 1994-November 1995 and January-December 1997. The assemblage is largely dominated by Copipodiaptomus steueri, a typical calanoid presently identified in deep (Garda, Iseo and shallow lakes of NE Italy and in the hinterland of the central Adriatic region (Dalmatia and Marche Region. Cladocerans and the smaller rotifers represent a significant component of the zooplankton from spring to autumn. A re-examination of the results obtained in previous studies does not seem to demonstrate substantial shifts in the composition of the dominant species. The only documentable and consolidated differences are constituted by the disappearance of Sida crystallina since the '50s and the appearance of new rotifers since the '70s and the '80s. It is stressed that, owing to the fragmentation of the available studies and the use of different methodologies, the qualitative and quantitative modifications of the zooplankton should be interpreted with special caution, requiring further in-depth and continuous monitoring for the meaning they could have as possible signs of modifications of the trophic structure of the lake. However, the results of the comparison of the different investigations do not seem to contrast with the substantial stability of the oligo-mesotrophic character of the lake formally documented since the '70s.

  17. Soil ecological interactions: comparisons between tropical and subalpine forests

    Science.gov (United States)

    Grizelle Gonzalez; Ruth E. Ley; Steven K. Schmidt; Xiaoming Zou; Timothy R. Seastedt

    2001-01-01

    Soil fauna can influence soil processes through interactions with the microbial community. Due to the complexity of the functional roles of fauna and their effects on microbes, little consensus has been reached on the extent to which soil fauna can regulate microbial activities. We quantified soil microbial biomass and maximum growth rates in control and fauna-excluded...

  18. Studies on the phytoplankton of the deep subalpine Lake Iseo

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    Rosario MOSELLO

    2003-08-01

    Full Text Available This paper reports the results of investigations carried out on the chemical characteristics and phytoplankton community of Lake Iseo. Samplings were performed on a monthly basis from 1998 to 2000. At least three main algal groups dominated the community throughout the study period. The large Bacillariophyceae were dominant mainly during late winter and early spring (Aulacoseira spp., Melosira varians, Asterionella formosa, with few species able to maintain occasional positive growth also during mid summer and/or autumn (Fragilaria crotonensis and Diatoma elongatum. The thermal stability of the water column and silica depletion were the main factors responsible for the decline of the large spring diatoms. The subsequent growth of Mougeotia sp. (Conjugatophyceae was favoured by its lower sinking rate and resistance to increasing grazing pressure by the dominant copepods (Copidodiaptomus steueri and cladocerans (Daphnia hyalina × galeata. Among the cyanobacteria, the greater development of Planktothrix rubescens in the autumn months, with conditions of vertical homogenisation and decreasing Zeu/Zmix ratios, was favoured by its ability to survive at low light irradiances. The temporal replacement of these three groups constitutes the main sequence of the annual phytoplankton succession in Lake Iseo. A large development of other algal groups was recorded only in one or two of the three study years (e.g. Dinophyceae and Chlorococcales. The changes observed in the annual phytoplankton development are discussed in the light of differences in the spring fertilisation of the waters, caused by differences in the depth of the layer involved in the late winter and spring vertical mixing.

  19. Semivolatile POA and parameterized total combustion SOA in CMAQv5.2: impacts on source strength and partitioning

    Science.gov (United States)

    Mounting evidence from field and laboratory observations coupled with atmospheric model analyses shows that primary combustion emissions of organic compounds dynamically partition between the vapor and particulate phases, especially as near-source emissions dilute and cool to amb...

  20. Post-harvest treatments in smooth-stalked meadow grass (Poa pratensis L.) - effect on carbohydrates and tiller development

    DEFF Research Database (Denmark)

    Boelt, Birte

    2007-01-01

    . The present investigation was initiated to investigate the effect of post-harvest treatments on dry matter production in autumn, carbohydrate content, the number of reproductive tillers and seed yield in a turf-type cultivar ‘Conni' of smooth-stalked meadow grass. The results show that post-harvest treatments...... harvest and all residues removed. The results from plant samples in autumn indicate that decreasing aboveground biomass production leads to a higher carbohydrate concentration which may stimulate the reproductive development in smooth-stalked meadow grass....

  1. Amending Subsoil with Composted Poultry Litter-II: Effects on Kentucky Bluegrass (Poa pratensis Establishment, Root Growth, and Weed Populations

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    Mili Mandal

    2013-10-01

    Full Text Available Turfgrasses established on a soil deprived of the topsoil during construction disturbance often have low levels of density and uniformity making them susceptible to weeds. Field experiments evaluated composted poultry litter incorporation into subsoil on Kentucky bluegrass growth attributes and subsequent effects on weed populations. Top 20 cm of topsoil was removed and composted poultry litter was incorporated at 0.1, or 0.2, or 0.4 cm/cm-soil into the exposed subsoil to a depth of 12.7 cm before seeding or sodding, and was compared to N-fertilized (50 × 10−4 kg m−2 and control plots. A greenhouse experiment was also conducted to determine the effect of compost incorporation rates on turfgrass rooting depth. Turfgrass yield from seeded plots with compost incorporation rates of 0.1, 0.2, and 0.4 cm/cm-soil, were 200%, 300%, and 500% more, respectively, compared to control plots. Composted poultry litter incorporated at 0.1 cm/cm-soil resulted in at least 70 seedlings in 7.6 cm−2, which was sufficient to attain 100% turf cover. Higher incorporation rates in seeded plots maintained lower numbers of buckhorn plantain and red clover than untreated plots. Rooting depth also increased linearly with compost rates. Overall, compost treatments were able to maintain superior turf cover and quality compared to conventionally fertilized or control plots.

  2. Geochemical evolution of the acid crater lake of Poas volcano (Costa Rica): Insights into volcanic-hydrothermal processes

    NARCIS (Netherlands)

    Martínez Cruz, María

    2008-01-01

    This thesis describes the evolution of Laguna Caliente, an acid crater lake at the summit of Po:is, a persistently active volcano in central Costa Rica. The appearance, volume, temperature and chemical composition of the lake have continuously changed over the entire known period of its

  3. Demography and dispersal ability of a threatened saproxylic beetle: a mark-recapture study of the Rosalia Longicorn (Rosalia alpina.

    Directory of Open Access Journals (Sweden)

    Lukas Drag

    Full Text Available The Rosalia longicorn or Alpine longhorn (Coleoptera: Cerambycidae is an endangered and strictly protected icon of European saproxylic biodiversity. Despite its popularity, lack of information on its demography and mobility may compromise adoption of suitable conservation strategies. The beetle experienced marked retreat from NW part of its range; its single population survives N of the Alps and W of the Carpathians. The population inhabits several small patches of old beech forest on hill-tops of the Ralska Upland, Czech Republic. We performed mark-recapture study of the population and assessed its distribution pattern. Our results demonstrate the high mobility of the beetle, including dispersal between hills (up to 1.6 km. The system is thus interconnected; it contained ∼2000 adult beetles in 2008. Estimated population densities were high, ranging between 42 and 84 adult beetles/hectare a year. The population survives at a former military-training ground despite long-term isolation and low cover of mature beech forest (∼1%. Its survival could be attributed to lack of forestry activities between the 1950s and 1990s, slow succession preventing canopy closure and undergrowth expansion, and probably also to the distribution of habitat patches on conspicuous hill-tops. In order to increase chances of the population for long term survival, we propose to stop clear-cuts of old beech forests, increase semi-open beech woodlands in areas currently covered by conifer plantations and active habitat management at inhabited sites and their wider environs.

  4. Demography and dispersal ability of a threatened saproxylic beetle: a mark-recapture study of the Rosalia Longicorn (Rosalia alpina).

    Science.gov (United States)

    Drag, Lukas; Hauck, David; Pokluda, Pavel; Zimmermann, Kamil; Cizek, Lukas

    2011-01-01

    The Rosalia longicorn or Alpine longhorn (Coleoptera: Cerambycidae) is an endangered and strictly protected icon of European saproxylic biodiversity. Despite its popularity, lack of information on its demography and mobility may compromise adoption of suitable conservation strategies. The beetle experienced marked retreat from NW part of its range; its single population survives N of the Alps and W of the Carpathians. The population inhabits several small patches of old beech forest on hill-tops of the Ralska Upland, Czech Republic. We performed mark-recapture study of the population and assessed its distribution pattern. Our results demonstrate the high mobility of the beetle, including dispersal between hills (up to 1.6 km). The system is thus interconnected; it contained ∼2000 adult beetles in 2008. Estimated population densities were high, ranging between 42 and 84 adult beetles/hectare a year. The population survives at a former military-training ground despite long-term isolation and low cover of mature beech forest (∼1%). Its survival could be attributed to lack of forestry activities between the 1950s and 1990s, slow succession preventing canopy closure and undergrowth expansion, and probably also to the distribution of habitat patches on conspicuous hill-tops. In order to increase chances of the population for long term survival, we propose to stop clear-cuts of old beech forests, increase semi-open beech woodlands in areas currently covered by conifer plantations and active habitat management at inhabited sites and their wider environs.

  5. 78 FR 30961 - Notice of Receipt of Petition for Decision that Nonconforming 2005-2007 Alpina B5 Passenger Cars...

    Science.gov (United States)

    2013-05-23

    ..., 103 Windshield Defrosting and Defogging Systems, 104 Windshield Wiping and Washing Systems, 106 Brake Hoses, 109 New Pneumatic Tires, 113 Hood Latch System, 116 Motor Vehicle Brake Fluids, 124 Accelerator Control Systems, 135 Light Vehicle Brake Systems, 201 Occupant Protection in Interior Impact, 202 Head...

  6. Ginger and the beetle: Evidence of primitive pollination system in a Himalayan endemic alpine ginger (Roscoea alpina, Zingiberaceae)

    National Research Council Canada - National Science Library

    Babu Ram Paudel; Mani Shrestha; Adrian G Dyer; Qing-Jun Li

    2017-01-01

    The Himalayan endemic alpine genus Roscoea, like other members of ginger family, exhibits the combination of floral traits that would fit pollination by long distant foragers such as bees, birds or flies...

  7. De lange weg

    NARCIS (Netherlands)

    Maas Geesteranus, R.A.

    1968-01-01

    Peziza alpina (Fuck.) Cooke (1876) and Peziza alpina (Fuck.) Oud. (1885) are recombinations based on Humaria alpina Fuck. (1874), and have no relation with Peziza alpina Sauter (1878). While the identity of Fuckel’s species is left out of consideration (as it will be discussed in a future paper),

  8. Apomixis is not prevalent in subnival to nival plants of the European Alps.

    Science.gov (United States)

    Hörandl, Elvira; Dobeš, Christoph; Suda, Jan; Vít, Petr; Urfus, Tomáš; Temsch, Eva M; Cosendai, Anne-Caroline; Wagner, Johanna; Ladinig, Ursula

    2011-08-01

    High alpine environments are characterized by short growing seasons, stochastic climatic conditions and fluctuating pollinator visits. These conditions are rather unfavourable for sexual reproduction of flowering plants. Apomixis, asexual reproduction via seed, provides reproductive assurance without the need of pollinators and potentially accelerates seed development. Therefore, apomixis is expected to provide selective advantages in high-alpine biota. Indeed, apomictic species occur frequently in the subalpine to alpine grassland zone of the European Alps, but the mode of reproduction of the subnival to nival flora was largely unknown. The mode of reproduction in 14 species belonging to seven families was investigated via flow cytometric seed screen. The sampling comprised 12 species typical for nival to subnival plant communities of the European Alps without any previous information on apomixis (Achillea atrata, Androsace alpina, Arabis caerulea, Erigeron uniflorus, Gnaphalium hoppeanum, Leucanthemopsis alpina, Oxyria digyna, Potentilla frigida, Ranunculus alpestris, R. glacialis, R. pygmaeus and Saxifraga bryoides), and two high-alpine species with apomixis reported from other geographical areas (Leontopodium alpinum and Potentilla crantzii). Flow cytometric data were clearly interpretable for all 46 population samples, confirming the utility of the method for broad screenings on non-model organisms. Formation of endosperm in all species of Asteraceae was documented. Ratios of endosperm : embryo showed pseudogamous apomixis for Potentilla crantzii (ratio approx. 3), but sexual reproduction for all other species (ratios approx. 1·5). The occurrence of apomixis is not correlated to high altitudes, and cannot be readily explained by selective forces due to environmental conditions. The investigated species have probably other adaptations to high altitudes to maintain reproductive assurance via sexuality. We hypothesize that shifts to apomixis are rather connected

  9. Soil water flow is a source of the plant pathogen Pseudomonas syringae in subalpine headwaters.

    OpenAIRE

    Monteil, Caroline; LAFOLIE, Francois; Laurent, Jimmy; Clement, Jean-Christophe; Simler, Roland; Travi, Yves

    2014-01-01

    The air-borne plant pathogenic bacterium Pseudomonas syringae is ubiquitous in headwaters, snowpack and precipitation where its populations are genetically and phenotypically diverse. Here, we assessed its population dynamics during snowmelt in headwaters of the French Alps. We revealed a continuous and significant transport of P. syringae by these waters in which the population density is correlated with water chemistry. Via in situ observations and laboratory experiments, we validated that ...

  10. Macroinvertebrate response to flow changes in a subalpine stream: predictions from two-dimensional hydrodynamic models

    Science.gov (United States)

    Waddle, T.J.; Holmquist, J.G.

    2013-01-01

    Two-dimensional hydrodynamic models are being used increasingly as alternatives to traditional one-dimensional instream flow methodologies for assessing adequacy of flow and associated faunal habitat. Two-dimensional modelling of habitat has focused primarily on fishes, but fish-based assessments may not model benthic macroinvertebrate habitat effectively. We extend two-dimensional techniques to a macroinvertebrate assemblage in a high-elevation stream in the Sierra Nevada (Dana Fork of the Tuolumne River, Yosemite National Park, CA, USA). This stream frequently flows at less than 0.03?m3?s?1 in late summer and is representative of a common water abstraction scenario: maximum water abstraction coinciding with seasonally low flows. We used two-dimensional modelling to predict invertebrate responses to reduced flows that might result from increased abstraction. We collected site-specific field data on the macroinvertebrate assemblage, bed topography and flow conditions and then coupled a two-dimensional hydrodynamic model with macroinvertebrate indices to evaluate habitat across a range of low flows. Macroinvertebrate indices were calculated for the wetted area at each flow. A surrogate flow record based on an adjacent watershed was used to evaluate frequency and duration of low flow events. Using surrogate historical records, we estimated that flow should fall below 0.071?m3?s?1 at least 1?day in 82 of 95?years and below 0.028?m3?s?1 in 48 of 95?years. Invertebrate metric means indicated minor losses in response to modelled discharge reductions, but wetted area decreased substantially. Responses of invertebrates to water abstraction will likely be a function of changing habitat quantity rather than quality.

  11. Last millennium multiproxy high-resolution palaeoenvironmental study based on a subalpine peatland

    Science.gov (United States)

    Lamentowicz, Mariusz; van der Knaap, Willem O.; van Leeuwen, Jacqueline F. N.; Hangartner, Sarah; Lamentowicz, Łukasz; Mitchell, Edward A. D.; Mauquoy, Dmitri; Kamenik, Christian; Goslar, Tomasz

    2010-05-01

    Subfossil testate amoebae (Protists) and stable oxygen isotopes supported by pollen were used to reconstruct the hydrological history of the last 1000 years from Mauntschas mire in the south-eastern Swiss Alps (Upper Engadin valley; 1818 m a.s.l.). This peatland, located at the bottom of an Alpine valley, recorded local hydrological changes that could be related to precipitation/temperature changes since AD 1000. Using a testate-amoeba training set, which was developed from samples collected in 2007 from peatlands in the same valley, we reconstructed depth to the water table (DWT) in Mauntschas mire. During the instrumental period (starting AD 1864), DWT were correlated with measured temperatures and winter precipitation. Over the last millennium the following changes were inferred: (i) since AD 1000 the presence of Archerella flavum indicated wet conditions; (ii) the habitat became moistest towards AD 1300; (iii) after AD 1300 testate amoebae indicated a gradual decrease of the water table; (iv) during AD 1580-1630 A. flavum indicated increased moisture - this wet period coincided with a cold anomaly recorded in the Alps; (v) between AD 1670 and 1715 the water table decreased again; (vi) another pronounced wet phase was recorded AD 1715-1850 with the maximum water table ca. AD 1780; (vii) during the instrumental period (1864-2003) the water table decreased gradually, following the trend of increasing temperatures. Among the pollen, the maximum wetness during the Little Ice Age (ca AD 1800) was reflected by pollen maxima of Cyperaceae and Selaginella. When climate became warmer and drier after AD 1850 (end of the Little Ice Age), Sphagnum spores were abundant. There was good agreement between DWT and the Pinus non-cembra pollen, suggesting temperature as the common driving factor. The stable oxygen isotopes (d18O) from Sphagnum stems showed similarities with DWT, with an anti-correlated phase at the end of the 19th century.

  12. Does the aboveground herbivore assemblage influence soil bacterial community composition and richness in subalpine grasslands?

    Science.gov (United States)

    Melanie Hodel; Martin Schütz; Martijn L. Vandegehuchte; Beat Frey; Matthias Albrecht; Matt D. Busse; Anita C. Risch

    2014-01-01

    Grassland ecosystems support large communities of aboveground herbivores that can alter ecosystem processes. Thus, grazing by herbivores can directly and indirectly affect belowground properties such as the microbial community structure and diversity. Even though multiple species of functionally different herbivores coexist in grassland ecosystems, most studies have...

  13. A New P System to Model the Subalpine and Alpine Plant Communities

    OpenAIRE

    Colomer, M. Angels; Fondevilla, Cristian; Valencia Cabrera, Luis

    2011-01-01

    In this work we present a P system based model of the ecosystem dynamics of plant communities. It is applied to four National Hunting Reservoirs in Catalan Pyrenees (Spain). In previous works several natural high- mountain- ecosystems and population dynamics were modeled, but in those works grass was considered unlimited and changes in plant communities were not taken into account. In our new model we take advantage of the modularity of P systems, adding the plant communities t...

  14. Atmospheric deposition chemistry in a subalpine area of the Julian Alps, NW Slovenia

    Directory of Open Access Journals (Sweden)

    Gregor Muri

    2013-04-01

    Full Text Available Wet-only precipitation was collected in Rateče, a remote village in the outskirts of the Julian Alps (Nort-West Slovenia during 2003-2011, in order to characterise atmospheric deposition chemistry. The samples were collected on a daily basis and combined into weekly samples that were analysed for pH, conductivity and major anions and cations. Ammonium, nitrate and sulphate were the most abundant ions, exhibiting volume-weighted mean values (2003-2011 of 22, 17 and 17 µeq L–1, respectively. Furthermore, the trends of the major parameters in the precipitation were assessed using a simple linear regression. A significant downward trend of both nitrate and sulphate was observed, explained by evident reductions in NOx and SOx emissions in the region. The decline of nitrate and sulphate was also reflected in a significant and downward trend of conductivity. While the trend of ammonium could also be downward, the trends of other major ions were not significant. Atmospheric nitrogen deposition, representing inorganic forms of nitrogen (i.e., ammonium and nitrate, was calculated to examine potential threats that the deposition of nitrogen may cause on lake ecosystems. Nitrogen deposition in Rateče ranged from 5.5 to 9.5 kg N ha–1 yr–1. Although this was below the critical threshold that might cause an impact on surface waters, nitrogen deposition in the nearby Julian Alps, where sensitive mountain lakes are situated, might be higher and its impact on the ecosystem greater. In fact, several studies performed on water chemistry, sedimentary organic matter and stable isotopes in Slovenian mountain lakes have shown progressive changes in their water columns and sediments that can be attributed to nitrogen deposition.

  15. Provenance variation in subalpine fir grown as an exotic tree species in Denmark and Iceland

    DEFF Research Database (Denmark)

    Skúlason, Brynjar

    in a period of 15 growing seasons after establishment. Provenances showed significant differences for all measured traits. The northernmost provenances showed earliest bud set, highest autumn frost tolerance and a latitudinal cline was delineated, while the southernmost provenances showed earliest flushing...

  16. Responses of Sap Flow of Deciduous and Conifer Trees to Soil Drying in a Subalpine Forest

    Directory of Open Access Journals (Sweden)

    Chunhua Yan

    2018-01-01

    Full Text Available Co-occurring species may adopt different water-use strategies to adapt to limited soil water. In Jiuzhaigou Valley, a continuous decline in soil water after an initial recharge from the thawing of snow and frozen soil in early spring was observed, but its effects on the sap flow dynamics of co-occurring species are not well understood. To clarify the species-specific water-use strategy, variations in sap flow and environmental conditions were investigated for two co-occurring species (Betula albosinensis Burk. and Pinus tabuliaeformis Carr. in a mixed forest during a transition from the wet to dry period in 2014. Sap flow was measured using Granier-type thermal dissipation probes, and the soil-water content was measured using time-domain reflectometry probes for a successive period. Our study showed that B. albosinensis maintained relatively high transpiration until late into the season regardless of soil moisture, while the transpiration of P. tabuliformis showed a continuous decrease in response to seasonal soil drying. Sap flow for both species exhibited a marked hysteresis in response to meteorological factors and it was conditioned by the soil-water status, especially in the afternoon. We found that P. tabuliformis was sensitive to soil-water conditions, while for B. albosinensis, the sap flow was not very sensitive to changes in soil-water conditions. These results indicate that B. albosinensis could manage the water consumption conservatively under both dry and wet conditions. These results may have implications for evaluating the species-specific water-use strategy and carrying out proper reforestation practices.

  17. Climate Change Impacts on Sediment Quality of Subalpine Reservoirs: Implications on Management

    Directory of Open Access Journals (Sweden)

    Marziali Laura

    2017-09-01

    Full Text Available Reservoirs are characterized by accumulation of sediments where micropollutants may concentrate, with potential toxic effects on downstream river ecosystems. However, sediment management such as flushing is needed to maintain storage capacity. Climate change is expected to increase sediment loads, but potential effects on their quality are scarcely known. In this context, sediment contamination by trace elements (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn and organics (Polycyclic Aromatic Hydrocarbons PAHs, Polychlorinated Biphenyls PCBs and C > 12 hydrocarbons was analyzed in 20 reservoirs located in Italian Central Alps. A strong As and a moderate Cd, Hg and Pb enrichment was emphasized by Igeo, with potential ecotoxicological risk according to Probable Effect Concentration quotients. Sedimentation rate, granulometry, total organic carbon (TOC and altitude resulted as the main drivers governing pollutant concentrations in sediments. According to climate change models, expected increase of rainfall erosivity will enhance soil erosion and consequently the sediment flow to reservoirs, potentially increasing coarse grain fractions and thus potentially diluting pollutants. Conversely, increased weathering may enhance metal fluxes to reservoirs. Increased vegetation cover will potentially result in higher TOC concentrations, which may contrast contaminant bioavailability and thus toxicity. Our results may provide elements for a proper management of contaminated sediments in a climate change scenario aiming at preserving water quality and ecosystem functioning.

  18. Four years of experimental warming do not modify the interaction between subalpine shrub species.

    Science.gov (United States)

    Anadon-Rosell, Alba; Ninot, Josep M; Palacio, Sara; Grau, Oriol; Nogués, Salvador; Navarro, Enrique; Sancho, M Carmen; Carrillo, Empar

    2017-04-01

    Climate warming can lead to changes in alpine plant species interactions through modifications in environmental conditions, which may ultimately cause drastic changes in plant communities. We explored the effects of 4 years of experimental warming with open-top chambers (OTC) on Vaccinium myrtillus performance and its interaction with neighbouring shrubs at the Pyrenean treeline ecotone. We examined the effects of warming on height, above-ground (AG) and below-ground (BG) biomass and the C and N concentration and isotope composition of V. myrtillus growing in pure stands or in stands mixed with Vaccinium uliginosum or Rhododendron ferrugineum. We also analysed variations in soil N concentrations, rhizosphere C/N ratios and the functional diversity of the microbial community, and evaluated whether warming altered the biomass, C and N concentration and isotope composition of V. uliginosum in mixed plots. Our results showed that warming induced positive changes in the AG growth of V. myrtillus but not BG, while V. uliginosum did not respond to warming. Vaccinium myrtillus performance did not differ between stand types under increased temperatures, suggesting that warming did not induce shifts in the interaction between V. myrtillus and its neighbouring species. These findings contrast with previous studies in which species interactions changed when temperature was modified. Our results show that species interactions can be less responsive to warming in natural plant communities than in removal experiments, highlighting the need for studies involving the natural assembly of plant species and communities when exploring the effect of environmental changes on plant-plant interactions.

  19. Modeling vegetation mosaics in sub-alpine Tasmania under various fire regimes

    Science.gov (United States)

    Gabriel I. Yospin; Samuel W. Wood; Andres Holz; David M. J. S. Bowman; Robert E. Keane; Cathy Whitlock

    2015-01-01

    Western Tasmania, Australia contains some of the highest levels of biological endemism of any temperate region in the world, including vegetation types that are conservation priorities: fire-sensitive rainforest dominated by endemic conifer species in the genus Athrotaxis; and firetolerant buttongrass moorlands. Current management focuses on fire suppression,...

  20. Ontogenetic niche shifts in three Vaccinium species on a sub-alpine mountain side

    DEFF Research Database (Denmark)

    Auffret, Alistair G.; Meineri, Eric; Bruun, Hans Henrik

    2010-01-01

    Background: Climate warming in arctic and alpine regions is expected to result in the altitudinal migration of plant species, but current predictions neglect differences between species' regeneration niche and established niche. Aims: To examine potential recruitment of Vaccinium myrtillus, V....... uliginosum and V. vitis-idaea on a mountain slope in northern Sweden in relation to current adult occurrence. Methods: We combined a seed-sowing experiment in seven community types with adult occurrence observations and species distribution mapping. Results: Emergence of V. myrtillus and V. vitis......-idaea seedlings was significantly related to community type, while V. uliginosum was indifferent, but exhibited the highest average emergence. Adult occurrence was related to community, and ontogenetic niche shifts were observed for all three study species. V. myrtillus was shown to have the highest potential...

  1. Spatial structure of a natural mixed topodeme of subalpine Sorbus taxa

    Directory of Open Access Journals (Sweden)

    Dušan Gömöry

    2011-01-01

    Full Text Available Spatial distribution and genetic variation of a population of Sorbus chamaemespilus (L. Crantz and putative hybrids between S. chamaemespilus, S. aria and S. aucuparia growing in the nature reserve Skalnä Alpa (central Slovakia were studied. The analysis of spatial patterns using Ripley's K-function revealed a significant clustering of the adults of both S. chamaemespilus and hybrid taxa at distances up to ~15 m and a strong affinity between both taxonomical groups, indicating similar ecological requirements. Bivariate point-pattern analysis considering cardinal direction showed that juvenile individuals of S. chamaemespilus are clustered around the adults up to the distance of ~2 m, whereas in hybrid taxa with larger and more dense crowns, juveniles are clustered at distances more than ~3 m from the adults. The analysis of genetic variation in a subset of adult shrubs using 4 nuclear microsatellite loci revealed that unlike expected, there was no variation in S. chamaemespilus but several genotypes were found in the group of hybrid taxa. Implications for the reproduction system and conservation of the investigated taxa are discussed.

  2. Tree squirrel habitat selection and predispersal seed predation in a declining subalpine conifer

    Science.gov (United States)

    Shawn T. McKinney; Carl E. Fiedler

    2009-01-01

    Differential responses by species to modern perturbations in forest ecosystems may have undesirable impacts on plant-animal interactions. If such disruptions cause declines in a plant species without corresponding declines in a primary seed predator, the effects on the plant could be exacerbated. We examined one such interaction between Pinus...

  3. Isolated ecosystems on supercooled scree slopes in subalpine environments - interaction between permafrost, soil and vegetation

    Science.gov (United States)

    Schwindt, Daniel; Kozák, Johanna-Luise; Kohlpaintner, Michael

    2017-04-01

    In the central European Alps, permafrost can be expected in altitudes above 2300 m a.s.l., where mean annual air temperatures are below -1°C. However, attributed to the thermally induced "chimney effect", isolated permafrost lenses can be found in scree slopes far below the timberline where mean annual air temperature is positive. Usually the supercooled subsurface appears as lenses at the foot of talus slopes, covered by a thick layer of organic material and a unique vegetation composition most obviously characterized by dwarf grown trees ("Hexenwäldli") and azonal plant species. The fact that mean annual air temperature is positive and therefore can be excluded as a driving factor makes these sites unique for studying interdependencies between a supercooled subsurface, plant adaptation and vegetation sociology as well as the soil development. Three study sites in the Swiss Alps, differing in altitude and substrate (granite, dolomite, limestone) were investigated. Studies covered the permafrost-affected central parts of the slope as well as the surrounding areas. For characterizing distribution and temporal variability of ground ice geophysical methods were applied (electrical resistivity- and seismic refraction tomography). Temperature data loggers were used for monitoring the thermal regime (air-, surface- and soil temperatures). Chemical parameters (pH, C/N ratio) and nutrient contents (N, P, Ca, Mg, Mn, K) were analyzed in different depth levels. Plant communities were analyzed with the Braun-Blanquet method. To characterize physiognomic adaptation of trees, transects have been determined parallel to slope, measuring tree height, diameter and age. Results show a strong spatial correlation between frozen ground, formation of a thick organic layer (Tangelhumus), azonal plant species distribution and pronounced dwarfing of trees. Surrounding areas with unfrozen subsurface show an - for the particular altitude - expected species and soil composition and normal forest growth. Ellenberg pointer values in central parts of the study sites showed a strong plant adaption to cold temperatures. However, plant sociological analysis did not indicate one clear azonal community, but two different permafrost-plant-communities, one adapted to acidic and the other to calcareous substrates. Dwarf grown trees (e.g. spruce, 63cm high, 122 years old) could be found in permafrost-affected areas of all study sites, while the same species developed normally in the surroundings. Main factor for the physiognomic adaptation seems to be the low temperature in the rooting zone and the correlated shorter vegetation period, as air temperatures and nutrient supplies between the permafrost affected area and its surroundings are comparable. Pronounced interdependencies between frozen ground distribution, vegetation cover and soil development could be verified for all sites. The supercooled subsurface causes reduced decomposition of organic material as well as dwarfing of trees. In return, Tangelhumus and dwarfed trees positively affect supercooling. Dry organic material thermally insulates the subsurface during summer and prevents/delays thawing, while the high thermal conductivity of the moist or frozen Tangelhumus enhances heat flow and supercooling in winter. In addition, dwarfed trees prevent the formation of a consistent insulating snow cover optimizing thermal fluxes between atmosphere and subsurface.

  4. Physical constraints in the deep hypolimnion of a subalpine lake driving planktonic Bacteria and Archaea distribution

    Directory of Open Access Journals (Sweden)

    Roberto Bertoni

    2010-06-01

    Full Text Available The study of the hydrodynamics of the hypolimnion of a deep holo-oligomictic lake (Lake Maggiore, Northern Italy, zmax¼370 m during the last 28 years showed that hypolimnetic waters remained isolated, not exchanging with the mixing zone even in winter when the full overturn conditions are most likely. The thickness of the isolated layer can range from 100 to 300 m. Thus, water masses of variable size reside in the lake for many years, and their physical and chemical conditions remain relatively unaffected by seasonal variability and epilimnetic imputs. In the hypolimnetic waters prokaryote abundance is three times lower than in the mixing layer but cell size is significantly higher. In addition, the relative abundance of Archaea and Crenarchaeota increases with depth in respect to that of Bacteria. The heterogeneous distribution of the two domains within the habitat can be attributed to the existence in the same environment of isolated water masses.

  5. Subalpine meadow plant communities in Yosemite and Sequoia and Kings Canyon National Parks, 2011-2012

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This publication presents data collected within meadows from samples used to assess meadow plant community responses to recreational pack stock as part of a USGS...

  6. Warming-induced upslope advance of subalpine forest is severely limited by geomorphic processes

    Science.gov (United States)

    Macias-Fauria, Marc; Johnson, Edward A.

    2013-01-01

    Forests are expected to expand into alpine areas because of climate warming, causing land-cover change and fragmentation of alpine habitats. However, this expansion will only occur if the present upper treeline is limited by low-growing season temperatures that reduce plant growth. This temperature limitation has not been quantified at a landscape scale. Here, we show that temperature alone cannot realistically explain high-elevation tree cover over a >100-km2 area in the Canadian Rockies and that geologic/geomorphic processes are fundamental to understanding the heterogeneous landscape distribution of trees. Furthermore, upslope tree advance in a warmer scenario will be severely limited by availability of sites with adequate geomorphic/topographic characteristics. Our results imply that landscape-to-regional scale projections of warming-induced, high-elevation forest advance into alpine areas should not be based solely on temperature-sensitive, site-specific upper-treeline studies but also on geomorphic processes that control tree occurrence at long (centuries/millennia) timescales. PMID:23569221

  7. The impact of toxic cyanobacteria on the water quality in the Deep Subalpine Lakes (DSL)

    Science.gov (United States)

    Cerasino, Leonardo; Shams, Shiva; Salmaso, Nico; Dietrich, Daniel

    2013-04-01

    Toxic cyanobacteria represent an emerging threat for aquatic ecosystems worldwide. Eutrophication and climate changes are mentioned among factors favouring toxic blooms. The toxicity of cyanobacteria is related to the ability of some species (the most common in temperate waters belong to the genera Microcystis, Planktothrix, Dolichospermum) of producing a wide variety of toxic secondary metabolites, i.e. microcystins, nodularins, anatoxins, saxitoxins, cylindrospermopsins. Some of these toxins can accumulate in water and aquatic organisms. They can therefore produce severe effects on humans by direct exposure (contact or ingestion of contaminated water) or by indirect exposure (by consumption of contaminated food). We have conducted a survey on the distribution of cyanobacterial toxins in the largest Italian lakes (Garda, Iseo, Como, Maggiore, Lugano), which are important water resources for drinking purposes and for recreational use. Cyanobacterial toxins were present in all lakes, although with a big variability in concentration. More specifically, in the frame of the European project EULAKES, we have investigated in detail the temporal dynamics of the toxin production in Lake Garda, and the mechanisms of trophic transfer of the microcystins along the lacustrine food chain. By applying advanced analytical techniques based on LC-MS technologies, we were able to detect several microcystins at sub-ppb level and follow their variations during the year. The total concentrations of microcystins were strictly linked to the temporal and vertical dynamics of Planktothrix rubescens. Laboratory experiments allowed us to determine the kinetics of microcystin accumulation in zooplankton (daphnia magna).

  8. Soil fauna and plant litter decomposition in tropical and subalpine forests

    Science.gov (United States)

    G. Gonzalez; T.R. Seastedt

    2001-01-01

    The decomposition of plant residues is influenced by their chemical composition, the physical-chemical environment, and the decomposer organisms. Most studies interested in latitudinal gradients of decomposition have focused on substrate quality and climate effects on decomposition, and have excluded explicit recognition of the soil organisms involved in the process....

  9. Beyond CO2 - Tackling the full greenhouse gas budget of a sub-alpine forest ecosystem

    Science.gov (United States)

    Burri, Susanne; Merbold, Lutz; Meier, Philip; Eugster, Werner; Hörtnagl, Lukas; Buchmann, Nina

    2017-04-01

    In order to tackle the full greenhouse gas (GHG) budgets of forest ecosystems, it is desirable but challenging to quantify the three major GHGs, i.e. CO2, CH4 and N2O simultaneously in-situ. At the long-term forest research site Davos (Candidate Class I Ecosystem Station within the Integrated Carbon Observation System - ICOS), we have recently installed a state-of-the-art measuring system simultaneously to observe the three GHGs on a high temporal resolution and both within and above the forest canopy. Thereby, we combine above-canopy eddy covariance flux measurements and forest floor chamber flux measurements (using five custom-made fully automated chambers). Both systems are connected to a quantum cascade laser absorption spectrometer (QCL, Aerodyne) and measurements are switched between three hours of above-canopy and one hour of forest floor GHG flux measurements. Using this approach, we will be able to study the full GHG budget as well as the dynamics of the individual fluxes on two vertical levels within the forest using a single instrument. The first results presented here will highlight the suitability of this promising tool for quantifying the full GHG budget of forest ecosystems.

  10. Long-term landscape changes in a subalpine spruce-fir forest in central Utah, USA

    Science.gov (United States)

    Jesse L. Morris; R. Justin DeRose; Andrea R. Brunelle

    2015-01-01

    In Western North America, increasing wildfire and outbreaks of native bark beetles have been mediated by warming climate conditions. Bioclimatic models forecast the loss of key high elevation species throughout the region. This study uses retrospective vegetation and fire history data to reconstruct the drivers of past disturbance and environmental change....

  11. Aboveground vertebrate and invertebrate herbivore impact on net N mineralization in subalpine grasslands : Ecology

    NARCIS (Netherlands)

    Risch, Anita C.; Schütz, Martin; Vandegehuchte, Martijn L.; van der Putten, Wim H.; Duyts, Henk; Raschein, Ursina; Gwiazdowicz, Dariusz J.; Busse, Matt D.; Page-Dumroese, Deborah S.; Zimmermann, Stephan

    2015-01-01

    Aboveground herbivores have strong effects on grassland nitrogen (N) cycling. They can accelerate or slow down soil net N mineralization depending on ecosystem productivity and grazing intensity. Yet, most studies only consider either ungulates or invertebrate herbivores, but not the combined effect

  12. Aboveground vertebrate and invertebrate herbivore impact on net N mineralization in subalpine grasslands

    NARCIS (Netherlands)

    Risch, A.C.; Schütz, Martin; Vandegehuchte, Martijn L.; Putten, Van Der W.H.; Duyts, Henk; Raschein, Ursina; Gwiazdowicz, D.J.; Busse, M.D.; Page-Dumroese, D.S.; Zimmermann, Stephan

    2015-01-01

    Aboveground herbivores have strong effects on grassland nitrogen (N) cycling. They can accelerate or slow down soil net N mineralization depending on ecosystem productivity and grazing intensity. Yet, most studies only consider either ungulates or invertebrate herbivores, but not the combined

  13. Tree age, disturbance history, and carbon stocks and fluxes in subalpine Rocky Mountain forests

    Science.gov (United States)

    J.B. Bradford; R.A. Birdsey; L.A. Joyce; M.G. Ryan

    2008-01-01

    Forest carbon stocks and fluxes vary with forest age, and relationships with forest age are often used to estimate fluxes for regional or national carbon inventories. Two methods are commonly used to estimate forest age: observed tree age or time since a known disturbance. To clarify the relationships between tree age, time since disturbance and forest carbon storage...

  14. Producción, calidad de leche y metabolitos sanguíneos de cabras de raza alpina alimentadas con nopal (Opuntia ficus-indica)

    OpenAIRE

    Sánchez Ortega, Jorge Adalberto

    2009-01-01

    Toda la información (recurso en mano y/o lectura digital) del recurso y que ayude a descifrar su contenido. La producción caprina es una de las actividades rurales más extendidas entre los pobladores de la región semiárida de San Luis Potosí. En esta zona el nopal es una alternativa de forraje ara los animales, debido a su elevado contenido de agua, carbohidratos solubles, calcio y vitaminas; además de aportar proteína aunque en bajas cantidades. Sin embargo, hay información limita...

  15. National Dam Safety Program. Alpina Dam (Inventory Number NY 778), St. Lawrence River Basin, Lewis County, New York. Phase I Inspection Report,

    Science.gov (United States)

    1980-02-14

    Aive 2 X 72 &4 AREA 4 1 368X7Z: -T73(a *AteA (:, .r .Z 4r 4 . . S. ’. ., ’Ai I#,.2 Iso o 4. _,oz 1.40)9 Z.’(06 i 3 l4Ooo 4.11Z 6 1 .6115 Z..843. ’i 2000...8858. 689.5 46.75 I.N 1588Z. 691.1 46.75 PLAN Z STATION 6 MAXIMUM MAXINM TIME RATIO FLONCFS STAGEFT HOURS .51 9325. 689.6 47.Z5 1.1 16439 . 691.3 46.5

  16. Increase in Bcl2 expression of penile and prostate cells of Sprague Dawley male rats following treatment with buceng (combination of Pimpinella alpina molk with Eurycoma longifolia Jack

    Directory of Open Access Journals (Sweden)

    Taufiqurrachman Nasihun

    2015-04-01

    Full Text Available Background: Treatment with buceng combination of Eurycoma longifolia Jack and Pimpinella alpine Molk has been proven to increase testosterone level, decrease apoptosis and caspase3 expression. Bcl2 is an antiapoptotic protein found in cytoplasm which inhibits cells apoptosis. This study was aimed to investigate the effect of buceng on Bcl2 expression on penile and prostate tissues of the rats. Methods: In this experimental study, 24 male Sprague Dawley rats of 90 days old, weighing ± 300 grams, were randomly assigned into four groups. Group A, normal rats. Group B, castrated rats and treated with buceng 100 mg/day, per oral (Cast-Bcg; Group C, castrated rats and treated with 2 ml of water as placebo against buceng (Cast-Plac. Group D, castrated rats, treated with mesterolone 6.75 mg/day, per oral, as exogenous testosterone (Cast-Mest. All rats were treated for 30 days. Manova test was used to analyze the different expression of Bcl2 among groups with significance level at p ≤ 0.05. Results: Castration was associated with significant decrease of Bcl2 expression in the penile and prostate tissues (53.0 and 50.9%, respectively compared to normal rats (82.6 and 84.2%, respectively, p < 0.001. Treatment with mesterolone reversed Bcl2 expression (77.1 and 78.1% to a near normal level. The same level of Bcl2 expression was also observed with buceng treatment (73.8 and 78.2%.Conclusion: The treatment with buceng could enhance Bcl2 expression in penile and prostate tissues, comparable to normal rats and mesterolone treated rats.

  17. Between‐patch natal dispersal declines with increasing natal patch size and distance to other patches in the endangered Southern Dunlin Calidris alpina schinzii

    National Research Council Canada - National Science Library

    Pakanen, Veli‐Matti; Koivula, Kari; Flodin, Lars‐Åke; Grissot, Antoine; Hagstedt, Robin; Larsson, Mikael; Pauliny, Angela; Rönkä, Nelli; Blomqvist, Donald

    2017-01-01

    .... Habitat fragmentation reduces structural connectivity by decreasing patch size and increasing isolation, but understanding of how this impacts dispersal and the functional connectivity of landscapes...

  18. What determines the densities of feeding birds on tidal flats? A case study on dunlin, Calidris alpina, in the Wadden Sea

    Science.gov (United States)

    Nehls, Georg; Tiedemann, Ralph

    The tidal and seasonal pattern of habitat utilization by dunlin was studied in a tidal-flat area in a shallow bay called Königshafen, island of Sylt, by counting the number of dunlins on marked plots at 10-min intervals over whole tidal cycles. Sediment type, tidal elevation, and seasonal changes in food choice were found to influence the feeding densities of dunlin irrespective of total numbers present in the area. Densities of dunlin were generally highest on low muddy substrates. A preference for high sandy substrates was found in late summer. The tidal pattern of habitat utilization differed between areas. In preferred areas dunlin stayed during the whole emersion period. Other areas were only used by following the moving tide line. Seasonal changes in habitat utilization were apparently triggered by changes in food choice. In spring dunlin fed almost exclusively on polychaetes. In late summer a relatively high proportion of shrimps, Crangon crangon, was found in the diet of dunlins. The preference for shrimps may force the birds to stay away from the tide line, where the shrimps can escape into deeper waters. It is recommended that studies on habitat utilization on tidal flats should consider the tidal behaviour of the target species, as single low-tide counts may not give valid results.

  19. Decreased expression of caspase3 in penis and prostate tissues of rat after the treatment with buceng (Pimpinella alpina Molk & Euricoma longifolia Jack

    Directory of Open Access Journals (Sweden)

    Taufiqurrachman Taufiqurrachman

    2013-02-01

    Full Text Available Background: Buceng {combination of pasak bumi (Eurycoma longifolia Jack and purwoceng (Pimpinella alpine Molk} has been proven to increase testosterone (Te level and decrease apoptosis. Unfortunately, there is no evidence whether these effects are mediated by the declining of caspase3. Objective of this study was to evaluate whether buceng could decrease the expression of caspase3 of penis and prostate cells in Sprague Dawley male rats.Methods: Twenty four Sprague Dawley male rats weighing 300 g (90 days old were randomly assigned into 4 groups of 6 male rats. Group A, rats were castrated and received buceng 50 mg. Group B, rats were not castrated, sacrifices as positive control. Group C, rats were castrated and given 2 mL aquadest as negative control. Group D, rats were castrated and got of 6.75 mg mesterolone, dissolved in 2 mL water. MANOVA statistical analysis was adopted to examine the difference expression of caspase3 in all groups. The comparison of caspase3 expression between two groups exhibiting difference values were evaluated by Post Hoc test.Results: MANOVA revealed statistically significant differences in the expression of caspase3 of penis and prostate tissues among the four groups. Post Hoct test also indicated that expression of caspase3 in group A (buceng (33.56; 35.83 was significantly lower compared to group C (negative control (54.33; 60.07 and group D (mesterolone (51.91;56.21, p = 0.000, and higher compared than group B or normal rats (29.40; 27.72, but statistically not significant (p = 0.826.Conclusion: The treatment of 50 mg buceng/day for 30 consecutive days could decrease caspase3 expression in penis and prostate cells. (Med J Indones. 2013;22:2-8Keywords: Apoptosis, buceng (Pimpinella alpine Molk – Eurycoma longifolia Jack, caspase3 

  20. Seasonal variations in the diet and foraging behaviour of dunlins Calidris alpina in a south European estuary: improved feeding conditions for northward migrants.

    Directory of Open Access Journals (Sweden)

    Ricardo C Martins

    Full Text Available During the annual cycle, migratory waders may face strikingly different feeding conditions as they move between breeding areas and wintering grounds. Thus, it is of crucial importance that they rapidly adjust their behaviour and diet to benefit from peaks of prey abundance, in particular during migration, when they need to accumulate energy at a fast pace. In this study, we compared foraging behaviour and diet of wintering and northward migrating dunlins in the Tagus estuary, Portugal, by video-recording foraging birds and analysing their droppings. We also estimated energy intake rates and analysed variations in prey availability, including those that were active at the sediment surface. Wintering and northward migrating dunlins showed clearly different foraging behaviour and diet. In winter, birds predominantly adopted a tactile foraging technique (probing, mainly used to search for small buried bivalves, with some visual surface pecking to collect gastropods and crop bivalve siphons. Contrastingly, in spring dunlins generally used a visual foraging strategy, mostly to consume worms, but also bivalve siphons and shrimps. From winter to spring, we found a marked increase both in the biomass of invertebrate prey in the sediment and in the surface activity of worms and siphons. The combination of these two factors, together with the availability of shrimps in spring, most likely explains the changes in the diet and foraging behaviour of dunlins. Northward migrating birds took advantage from the improved feeding conditions in spring, achieving 65% higher energy intake rates as compared with wintering birds. Building on these results and on known daily activity budgets for this species, our results suggest that Tagus estuary provides high-quality feeding conditions for birds during their stopovers, enabling high fattening rates. These findings show that this large wetland plays a key role as a stopover site for migratory waders within the East Atlantic Flyway.

  1. Synthesis of 1,3-dioleoyl-2-arachidonoylglycerol-rich structured lipids by lipase-catalyzed acidolysis of microbial oil from Mortierella alpina.

    Science.gov (United States)

    Abed, Sherif M; Zou, Xiaoqiang; Ali, Abdelmoneim H; Jin, Qingzhe; Wang, Xingguo

    2017-11-01

    Microbial oils (MOs) have gained widespread attention due to their functional lipids and health promoting properties. In this study, 1,3-dioleoyl-2-arachidonoylglycerol-rich structured lipids (SLs) were produced from MO and oleic acid (OA) via solvent-free acidolysis catalyzed by Lipozyme RM IM. Under the optimal conditions, the content of unsaturated fatty acids (UFAs) increased from 60.63 to 84.00%, while the saturated fatty acids (SFAs) content decreased from 39.37 to 16.00% at sn-1,3 positions in SLs. Compared with MO, arachidonic acid (ARA) content at the sn-2 position of SLs accounted for 49.71%, whereas OA was predominantly located at sn-1,3 positions (47.05%). Meanwhile, the most abundant triacylglycerol (TAG) species in SLs were (18:1-20:4-18:1), (20:4-20:4-18:1), (18:1-18:2-18:1), (18:1-18:2-18:0) and (24:0-20:4-18:1) with a relative content of 18.79%, 11.94%, 6.07%, 5.75% and 4.84%, respectively. Such novel SLs with improved functional properties enriched with UFAs are highly desirable and have the potential to be used in infant formula. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Rhizosphere microbial populations in contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Nichols, T.D.; Wolf, D.C.; Rogers, H.B.; Beyrouty, C.A.; Reynolds, C.M. [University of Arkansas, Fayetteville, AR (United States). Dept. of Agronomy

    1997-04-01

    Rhizosphere microbial populations may increase bioremediation of soil contaminated with organic chemicals. A growth chamber study was conducted to evaluate rhizosphere microbial populations in contaminated and non-contaminated soil. Alfalfa (Medicago sativa L.) and alpine bluegrass (Poa alpina L.) were grown in soil containing a mixture of organic chemicals for 14 weeks. The equal millimolar mixture of hexadecane, (2,2-dimethylpropyl)benzene, cis-decahydronaphthalene (decalin), benzoic acid, phenanthrene, and pyrene was added at levels of 0 and 2000 mg/kg. Organic chemical degrader (OCD) populations were assessed by a Most-Probable-Number technique, and bacteria and fungi were enumerated by plate count methods. Different methods for expressing OCD rhizosphere populations were enumerated by plate count methods. Different methods for expressing OCD rhizosphere populations were investigated to determine the effect it had on interpretation of the results. At 9 weeks, the OCD numbers were significantly higher in rhizosphere and contaminated soils than in bulk and non-contaminated soils, respectively. Alfalfa rhizosphere OCD levels were 4 x 10{sup 7}/g for contaminated and 6 x 10{sup 6}/g for non-contaminated soils. Bluegrass rhizosphere OCD levels were 1 x 10{sup 7}/g and 1 x 10{sup 6}/g in contaminated and non-contaminated soils, respectively. Selective enrichment of OCD populations was observed in contaminated rhizosphere soil. Higher numbers of OCD in contaminated rhizospheres suggest potential stimulation of bioremediation around plant roots. 36 refs., 10 tabs.

  3. Importance of Marine-Derived Nutrients Supplied by Planktivorous Seabirds to High Arctic Tundra Plant Communities.

    Directory of Open Access Journals (Sweden)

    Adrian Zwolicki

    Full Text Available We studied the relative importance of several environmental factors for tundra plant communities in five locations across Svalbard (High Arctic that differed in geographical location, oceanographic and climatic influence, and soil characteristics. The amount of marine-derived nitrogen in the soil supplied by seabirds was locally the most important of the studied environmental factors influencing the tundra plant community. We found a strong positive correlation between δ15N isotopic values and total N content in the soil, confirming the fundamental role of marine-derived matter to the generally nutrient-poor Arctic tundra ecosystem. We also recorded a strong correlation between the δ15N values of soil and of the tissues of vascular plants and mosses, but not of lichens. The relationship between soil δ15N values and vascular plant cover was linear. In the case of mosses, the percentage ground cover reached maximum around a soil δ 15N value of 8‰, as did plant community diversity. This soil δ15N value clearly separated the occurrence of plants with low nitrogen tolerance (e.g. Salix polaris from those predominating on high N content soils (e.g. Cerastium arcticum, Poa alpina. Large colonies of planktivorous little auks have a great influence on Arctic tundra vegetation, either through enhancing plant abundance or in shaping plant community composition at a local scale.

  4. Effects of temperature and light on the formation of chloroplast protrusions in leaf mesophyll cells of high alpine plants.

    Science.gov (United States)

    Buchner, Othmar; Holzinger, Andreas; Lütz, Cornelius

    2007-11-01

    Chloroplasts of many alpine plants have the ability to form marked, stroma-filled protrusions that do not contain thylakoids. Effects of temperature and light intensity on the frequency of chloroplasts with such protrusions in leaf mesophyll cells of nine different alpine plant species (Carex curvula All., Leontodon helveticus Merat., Oxyria digyna (L.) Hill., Poa alpina L. ssp. vivipara, Polygonum viviparum L., Ranunculus glacialis L., Ranunculus alpestris L., Silene acaulis L. and Soldanella pusilla Baumg.) covering seven different families were studied. Leaves were exposed to either darkness and a stepwise increase in temperature (10-38 degrees C) or to different light intensities (500 and 2000 micromol photons m(-2) s(-1)) and a constant temperature of 10 or 30 degrees C in a special temperature-regulated chamber. A chloroplast protrusions index characterising the relative proportion of chloroplasts with protrusions was defined. Seven of the nine species showed a significant increase in chloroplast protrusions when temperature was elevated to over 20 degrees C. In contrast, the light level did not generally affect the abundance of chloroplasts with protrusions. Chloroplast protrusions lead to a dynamic enlargement of the chloroplast surface area. They do not appear to be directly connected to a distinct photosystem II (PSII) (F(v)/F(m)) status and thus seem to be involved in secondary, not primary, photosynthetic processes.

  5. Importance of Marine-Derived Nutrients Supplied by Planktivorous Seabirds to High Arctic Tundra Plant Communities.

    Science.gov (United States)

    Zwolicki, Adrian; Zmudczyńska-Skarbek, Katarzyna; Richard, Pierre; Stempniewicz, Lech

    2016-01-01

    We studied the relative importance of several environmental factors for tundra plant communities in five locations across Svalbard (High Arctic) that differed in geographical location, oceanographic and climatic influence, and soil characteristics. The amount of marine-derived nitrogen in the soil supplied by seabirds was locally the most important of the studied environmental factors influencing the tundra plant community. We found a strong positive correlation between δ15N isotopic values and total N content in the soil, confirming the fundamental role of marine-derived matter to the generally nutrient-poor Arctic tundra ecosystem. We also recorded a strong correlation between the δ15N values of soil and of the tissues of vascular plants and mosses, but not of lichens. The relationship between soil δ15N values and vascular plant cover was linear. In the case of mosses, the percentage ground cover reached maximum around a soil δ 15N value of 8‰, as did plant community diversity. This soil δ15N value clearly separated the occurrence of plants with low nitrogen tolerance (e.g. Salix polaris) from those predominating on high N content soils (e.g. Cerastium arcticum, Poa alpina). Large colonies of planktivorous little auks have a great influence on Arctic tundra vegetation, either through enhancing plant abundance or in shaping plant community composition at a local scale.

  6. SYNTAXONOMY OF TUNDRA, CRYOPHYTIC STEPPE, NIVAL AND ALPINE MEADOWS IN THE HIGHLANDS OF THE SOUTHEAST ALTAI

    Directory of Open Access Journals (Sweden)

    M. Yu. Telyatnikov

    2015-04-01

    Full Text Available The material in this article supplements the results of the studies carried out by us earlier in the high mountains of the south-eastern Altai. Ten associations and 13 subassociations were described that are assigned to six classes of eco-floristic classification. Six associations and 13 subassociations are described the first time. Tundra vegetation is confined to northern slopes of ridges, while steppes occupy southern slopes of the mountains. Alpine altitudinal zone is dominated by Kobresia and Dryas tundra (associations Rhytidio rugosi-Oxytropidetum alpinae. In the subalpine zone dwarf birch thicket (ass. Hylocomio splendentis-Caricetum sabynensis and dwarf birch tundra (ass. Aulacomnio turgidi-Lagotidetum integrifoliae are common. This zone is also characterized by nival meadows (ass. Anthoxantho alpini-Schulzietum crinitae. Cryo-steppe belt is dominated by graminoid steppes (ass. Carici rupestris-Festucetum krylovianae in its upper part, while in the lower part forb graminoid cryophytic steppes (ass. Poo attenuatae-Festucetum tschujensis prevail. For the cryo-steppe belt species-rich alpine meadows (ass. Thalictro alpini-Trollietum asiatici, ass. Antennario dioicae-Pulsatilletum patentis are also typical.

  7. SPIDERS (ARANEI IN HEPRETOBIONT MESOFAUNA OF THE NORTHWEST CAUCASUS

    Directory of Open Access Journals (Sweden)

    A. V. Ponomarev

    2014-01-01

    Full Text Available Abstract. Aim. We discussed in previous work a herpetobiont fauna of arachnids (Arachnida from the isolated yewboxwood wood, located in the Caucasian State Biosphere Reserve, 20 km near Sochi (Ponomarev, Chumachenko, 2007. The aim of the paper is to summarize available data about herpetobiont araneofauna of the Northwest Caucasus. Location. Republic of Adygea, Russia.Methods. Material was collected in 2009 on north macroslope of Main Caucasian Ridge within the territory of the Caucasian State Biosphere Reserve between 1000–1820 m. The following plant communities are studied: beech-silver fir (assotiation Abieti-Fagetion orientalis Korotkov et Belonovskaya 1987, maple forest (assotiation Petasito albae-Abietetum nordmannianae subassotiation Aceretosum trautvetteri Francuzov 2006, subalpine meadow (assotiation Poa longifolii – Calamagrostietum arundinaceae Semagina, 1992. Soil traps were used for collection of spiders.Results and main conclusions. During the period of study 100 species of spiders from 19 families are registered. Most diverse araneofauna of subalpine meadows includs 54 species belonging to 14 families. The least diverse araneofauna is in maple forest (24 species of 7 families. In beech-silver fir includes 45 species of 16 families of spiders. Only 3 species (Pireneitega ovtchinnikovi, Cybaeus abchasicus, Tenuiphantes mengei were found in all surveyed habitats. These 3 species clearly tend to forest habitats. Herpetobiont araneofauna of the Northwest Caucasus characterized by high taxonomic diversity with clear predominance of representatives of the family Linyphiidae. Specificity of araneofauna in different types of plant communities is high.

  8. Incremental Formation of Dolomitic Vein Related To The Uzer Growth Fault Activity (ardeche Margin, Mesozoic Subalpine Basin of France)

    Science.gov (United States)

    Léost, I.; Ramboz, C.

    In order to document mass transfers in the Pb-Zn mineralized Ardèche passive mar- gin, two boreholes were drilled 1.2km apart from the Uzer growth fault which marks a limit between the continental plateform and the basin. The synsedimentary activity of the fault from Early Liassic to Bathonian results in a vertical downthrown of 1km to the SE. The basis of the Balazuc borehole core section (BA1, 1730-deep) is highly fracturated which testifies of the fault vicinity (from -1620m to -1730m). At BA1, middle Triassic beds lie unconformably on the Carboniferous rocks at -1669m. In up- per Paleozoic levels and Triassic levels, dolomitic microveins corresponding to either crack-seal, en echelon-cracks or tension gashes, suggest periodically high fluid pres- sure events. We have particularly studied dolomite around -1626m and 1620m major fractures. Most of the dolomite crystals, either in a shaly cement or in microveins, are optically zoned, due to fluid inclusions, matrix impureties and/or Fe-Mn rich bands. The core of crystals from cements are Mg-rich and fluid inclusion poor. The inner part of crystals from veins is locally Fe-rich and with numerous randomly distributed fluid inclusions, and magnesian and fluid inclusion free elsewhere. The outer part of vein and cement crystals are Fe-enriched (type saddle dolomite) and rich in fluid in- clusions underlining the growth zones. At levels -1624m, -1594m and -1581m, fluid inclusions from vein cores yield rather grouped Tmi and Th values (-22.6fluid inclusions outlining the outer growth zones from veins and cements yield more scattered Tmi and Th values (-17.4fluid. We suggest that dolomite in veins and cements around -1620m has recorded fluid pressure variations at the onset of the tectonic jurassic ac- tivity of the Uzer fault. Upward migration of a hydrothermal brine was first channel- ized by the fault system; Due to fault progressive displacement, the hydrothermal fluid pressure reached a critical level leading to hydrofracturing and crystallization of the vein centers. The decrease of pressure was then responsible for fluid escape around the fault and mixing with the connate brine. This lead to overgrowth crystallization of dolomite in cement and veins. This work illustrates the role of the fault transient 1 permeability in controlling fluid migration pathways but also rock diagenesis. 2

  9. Spatial and Temporal Variability of Soil Respiration Fluxes from Alpine and Subalpine Soils in the East River Watershed, Colorado

    Science.gov (United States)

    McCormick, M. E.; Winnick, M.; Rainaldi, G. R.; Lawrence, C. R.; Druhan, J. L.; Hsu, H. T.; Maher, K.

    2016-12-01

    Soil respiration of carbon to the atmosphere represents one of the largest fluxes of the terrestrial carbon cycle and is sensitive to changes in temperature, soil moisture, and processes affecting carbon stability. Despite the importance of these sensitivities, few studies have examined the spatial and temporal heterogeneity of soil CO2 fluxes and their controls on intermediate- to large-scale integrated soil fluxes. In this study, we examine spatial variability at scales of 10-5 -101 km2 and temporal variability at scales of hours to months of soil CO2 fluxes through the 2016 growing season in the East River Watershed, CO. We present analyses of (1) temporal variability of CO2 fluxes from four locations with depth-resolved temperature, moisture content, soil gas pCO2, and soil carbon content measurements; (2) spatial variability of CO2 fluxes and surface soil water content across a gridded hillslope with 74 points over an area of 2.5 x 10-3 km2 measured at multiple times throughout the growing season; and (3) variability of CO2 fluxes and surface soil water content from >20 point locations across the 85 km2 catchment targeting a range of vegetation, slope, and aspect characteristics. Comparing soil CO2 fluxes with depth-resolved temperature, moisture, pCO2 and carbon content, we calculate depth-resolved CO2 production rates and their correlations with soil conditions. Gridded hillslope flux measurements reveal strong and consistent variability across separation distances of 1 - 30 m with a slight dependence on slope position, likely representing the controls of lateral flow on soil moisture content. Finally, we analyze correlations of soil CO2 fluxes from point measurements representing broad-scale landscape units with vegetation and geomorphological characteristics. Combining these observations, we examine the implications of our results for interpolating point flux measurements to the catchment scale and for calculating integrated fluxes through the growing season.

  10. Soil distribution and soil properties in the subalpine region of Kazbegi; Greater Caucasus; Georgia: Soil quality rating of agricultural soils

    Directory of Open Access Journals (Sweden)

    Thomas Hanauer

    2017-03-01

    Full Text Available Soils of the alpine ecosystem of Kazbegi region were investigated according to the Muencheberg Soil Quality Rating (M-SQR. Most limiting factors are climate as well as steepness, while the low nutrient supply and soil acidity can be tackled by adequate fertilization and liming practice. Inorganic or organic pollution were not detected. Soils on sediment fans as well as glacial sediments, mostly Cambisols (Humic, are characterized by a low to moderate yield potential while high-yield soils, mostly Cambic Umbrisols, can be found on volcanic plateaus. A common element of all soils is the high humus content. Actually, most of them are used only for pasture, due to poor accessibility. Soils on fluvial deposits, mostly Fluvisols, show a very high range of M-SQR-scores. Altogether, the soils of the study area have the actually untapped potential to optimize the basic supply of the local population as well as tourism also by cultivation of cereals. Nevertheless, variety trials on different soil forming substrates as well as erosion control are major preconditions for successful implementation of new cropping systems in the Kazbegi region. Furthermore, particularly rare soils, e.g. Cambisols on Tephra, should be protected.

  11. Identifying Subalpine Fir (Abies lasiocarpa Attacked by the Balsam Woolly Adelgid (Adelges piceae Using Spectral Measurements of the Foliage

    Directory of Open Access Journals (Sweden)

    Stephen P. Cook

    2010-01-01

    Full Text Available Balsam woolly adelgid is an invasive pest of firs in the United States. Aerial surveys are conducted for detection of adelgid infestations but other remotely sensed data may also be useful. Our objective was to determine if high spectral resolution, branch-level data can be used to distinguish infested from noninfested trees. Stepwise discriminant analysis yielded a three-variable model (the red-green index and two narrow-bands (one at 670 nm and the other at 1912 nm that classified infested versus non-infested trees with 94% accuracy compared with the 83% accuracy obtained with a single-variable model. The response of trees in narrow spectral bands was integrated across wavebands to simulate measurements from the multispectral SPOT5-HRVIR sensor. Stepwise discriminant analysis again yielded a three-variable model (simple ratio, the SPOT5-HRVIR band in the SWIR region and NDVI with similar accuracy (93% at discriminating infested from non-infested trees compared with the 83% accuracy obtained with a single-variable model.

  12. (13)C NMR spectroscopy characterization of particle-size fractionated soil organic carbon in subalpine forest and grassland ecosystems.

    Science.gov (United States)

    Shiau, Yo-Jin; Chen, Jenn-Shing; Chung, Tay-Lung; Tian, Guanglong; Chiu, Chih-Yu

    2017-12-01

    Soil organic carbon (SOC) and carbon (C) functional groups in different particle-size fractions are important indicators of microbial activity and soil decomposition stages under wildfire disturbances. This research investigated a natural Tsuga forest and a nearby fire-induced grassland along a sampling transect in Central Taiwan with the aim to better understand the effect of forest wildfires on the change of SOC in different soil particle scales. Soil samples were separated into six particle sizes and SOC was characterized by solid-state (13)C nuclear magnetic resonance spectroscopy in each fraction. The SOC content was higher in forest than grassland soil in the particle-size fraction samples. The O-alkyl-C content (carbohydrate-derived structures) was higher in the grassland than the forest soils, but the alkyl-C content (recalcitrant substances) was higher in forest than grassland soils, for a higher humification degree (alkyl-C/O-alkyl-C ratio) in forest soils for all the soil particle-size fractions. High humification degree was found in forest soils. The similar aromaticity between forest and grassland soils might be attributed to the fire-induced aromatic-C content in the grassland that offsets the original difference between the forest and grassland. High alkyl-C content and humification degree and low C/N ratios in the fine particle-size fractions implied that undecomposed recalcitrant substances tended to accumulate in the fine fractions of soils.

  13. Atmospheric stability effects on wind fields and scalar mixing within and just above a subalpine forest in sloping terrain

    Science.gov (United States)

    Burns, Sean P.; Sun, Jielun; Lenschow, D.H.; Oncley, S.P.; Stephens, B.B.; Yi, C.; Anderson, D.E.; Hu, Jiawen; Monson, Russell K.

    2011-01-01

    Air temperature Ta, specific humidity q, CO2 mole fraction ??c, and three-dimensional winds were measured in mountainous terrain from five tall towers within a 1 km region encompassing a wide range of canopy densities. The measurements were sorted by a bulk Richardson number Rib. For stable conditions, we found vertical scalar differences developed over a "transition" region between 0.05 1), the vertical scalar differences reached a maximum and remained fairly constant with increasing stability. The relationships q and ??c have with Rib are explained by considering their sources and sinks. For winds, the strong momentum absorption in the upper canopy allows the canopy sublayer to be influenced by pressure gradient forces and terrain effects that lead to complex subcanopy flow patterns. At the dense-canopy sites, soil respiration coupled with wind-sheltering resulted in CO2 near the ground being 5-7 ??mol mol-1 larger than aloft, even with strong above-canopy winds (near-neutral conditions). We found Rib-binning to be a useful tool for evaluating vertical scalar mixing; however, additional information (e.g., pressure gradients, detailed vegetation/topography, etc.) is needed to fully explain the subcanopy wind patterns. Implications of our results for CO2 advection over heterogenous, complex terrain are discussed. ?? 2010 Springer Science+Business Media B.V.

  14. Pastoral practices to reverse shrub encroachment of sub-alpine grasslands: dung beetles (coleoptera, scarabaeoidea) respond more quickly than vegetation.

    Science.gov (United States)

    Tocco, Claudia; Probo, Massimiliano; Lonati, Michele; Lombardi, Giampiero; Negro, Matteo; Nervo, Beatrice; Rolando, Antonio; Palestrini, Claudia

    2013-01-01

    In recent decades, pastoral abandonment has produced profound ecological changes in the Alps. In particular, the reduction in grazing has led to extensive shrub encroachment of semi-natural grasslands, which may represent a threat to open habitat biodiversity. To reverse shrub encroachment, we assessed short-term effects of two different pastoral practices on vegetation and dung beetles (Coleoptera, Scarabaeoidea). Strategic placement of mineral mix supplements (MMS) and arrangement of temporary night camp areas (TNCA) for cattle were carried out during summer 2011 in the Val Troncea Natural Park, north-western Italian Alps. In 2012, one year after treatment, a reduction in shrub cover and an increase in bare ground cover around MMS sites was detected. A more intense effect was detected within TNCA through increases in forage pastoral value, and in the cover and height of the herbaceous layer. Immediately after treatment, changes in dung beetle diversity (total abundance, species richness, Shannon diversity, taxonomic and functional diversity) showed a limited disturbance effect caused by high cattle density. In contrast, dung beetle diversity significantly increased one year later both at MMS and TNCA sites, with a stronger effect within TNCA. Multivariate Regression Trees and associated Indicator Value analyses showed that some ecologically relevant dung beetle species preferred areas deprived of shrub vegetation. Our main conclusions are: i) TNCA are more effective than MMS in terms of changes to vegetation and dung beetles, ii) dung beetles respond more quickly than vegetation to pastoral practices, and iii) the main driver of the rapid response by dung beetles is the removal of shrubs. The resulting increase in dung beetle abundance and diversity, which are largely responsible for grassland ecosystem functioning, may have a positive effect on meso-eutrophic grassland restoration. Shrub encroachment in the Alps may therefore be reversed, and restoration of grassland enhanced, by using appropriate pastoral practices.

  15. Patterns of livestock activity on heterogeneous subalpine pastures reveal distinct responses to spatial autocorrelation, environment and management.

    Science.gov (United States)

    Homburger, Hermel; Lüscher, Andreas; Scherer-Lorenzen, Michael; Schneider, Manuel K

    2015-01-01

    In order to understand the impact of grazing livestock on pasture ecosystems, it is essential to quantify pasture use intensity at a fine spatial scale and the factors influencing its distribution. The observation and analysis of animal activity is greatly facilitated by remote tracking technology and new statistical frameworks allowing for rapid inference on spatially correlated data. We used these advances to study activity patterns of GPS-tracked cows in six summer-grazing areas in the Swiss Alps that differed in environmental conditions as well as livestock management. Recorded GPS positions were assigned to the activities of grazing, resting, and walking, and were discretized on a regular grid. Regression models with spatially structured effects were fitted to the spatial activity patterns using Integrated Nested Laplace Approximation. They indicated that terrain slope, forage quality, and stocking rate were the primary factors determining cow activity in the six study areas. Terrain slope significantly reduced livestock activity in five of the six areas and sparse forage availability significantly reduced grazing in all areas. In three areas, grazing pressure imposed by the pasture rotation was observable in the grazing pattern. Insolation, distance to the shed, and distance to water were less important for cow activity. In addition to the main factors identified across all study areas, we found effects operating only in individual areas, which were partly explained by specific environmental and management characteristics. In study areas with few paddocks, environmental variables exerted a stronger control on livestock activity than in areas with a short stocking period per paddock. The data demonstrated that a strict pasture rotation with short stocking periods is necessary to influence livestock activity, and hence potential effects on ecosystem processes. Without grazing management, livestock activity is primarily determined by the environment. Such insight is indispensable for studying relationships between grazing animals and ecosystem characteristics, and for developing management strategies to optimize ecosystem services. The analysis also highlighted the need for an appropriate statistical treatment of bio-logging data, since various estimates were biased if spatial autocorrelation was ignored.

  16. Evaluating the utility and seasonality of NDVI values for assessing post-disturbance recovery in a subalpine forest.

    Science.gov (United States)

    Buma, Brian

    2012-06-01

    Forest disturbances around the world have the potential to alter forest type and cover, with impacts on diversity, carbon storage, and landscape composition. These disturbances, especially fire, are common and often large, making ground investigation of forest recovery difficult. Remote sensing offers a means to monitor forest recovery in real time, over the entire landscape. Typically, recovery monitoring via remote sensing consists of measuring vegetation indices (e.g., NDVI) or index-derived metrics, with the assumption that recovery in NDVI (for example) is a meaningful measure of ecosystem recovery. This study tests that assumption using MODIS 16-day imagery from 2000 to 2010 in the area of the Colorado's Routt National Forest Hinman burn (2002) and seedling density counts taken in the same area. Results indicate that NDVI is rarely correlated with forest recovery, and is dominated by annual and perennial forb cover, although topography complicates analysis. Utility of NDVI as a means to delineate areas of recovery or non-recovery are in doubt, as bootstrapped analysis indicates distinguishing power only slightly better than random. NDVI in revegetation analyses should carefully consider the ecology and seasonal patterns of the system in question.

  17. Using landscape-level forest monitoring data to draw a representative picture of an iconic subalpine tree species

    Science.gov (United States)

    Sara A. Goeking; Deborah K. Izlar

    2015-01-01

    Whitebark pine (Pinus albicaulis) is an ecologically important species in high-altitude, mid-latitude areas of western North America due to the habitat and food source it provides for many wildlife species. Recent concerns about the long-term viability of whitebark pine stands have arisen in the face of high mortality due to a combination of fire...

  18. [Characteristics of soil respiration in artificial restoration process of subalpine coniferous forest in eastern Qinghai-Tibet plateau].

    Science.gov (United States)

    Zhou, Fei-Fei; Lin, Bo; Liu, Qing

    2009-08-01

    By the method of infrared CO2 determination in closed dynamic chamber system, the soil respiration in natural spruce forest, and 22-, 35-and 65-year old spruce plantations in eastern Qinghai-Tibet plateau was measured in situ, and the soil heterotrophic and autotrophic respiration was differentiated by entrenchment. In the four spruce forests, soil respiration rate had a significant positive exponential correlation with the soil temperature at depth 5 cm, but less correlation with the soil moisture content at the same depth. The annual soil respiration flux was 792.08-1070.20 g C x m(-2) x a (-1), and decreased in the order of natural spruce forest > 22-year old spruce plantation > 65-year old spruce plantation >35-year old spruce plantation. The annual soil autotrophic and heterotrophic respiration fluxes were 253.36-357.05 g C x m(-2) x a(-1) and 538.69-703.82 g C x m(-2) x a(-1), respectively, and had the same variation trend as the annual soil respiration flux. The Q10 value of soil respiration in 22-, 35-, and 65-year old spruce plantations and in natural spruce forest in growth season (from Nov. 2007 to Mar. 2008) and non-growth season (from Apr. 2008 to Oct. 2008) were 4.59, 6.54, 4.77, and 3.18, and 4.17, 4.66, 3.11, and 2.74, respectively. Except that in 22-year old spruce plantation, the Q10 value was decreased with increasing restoration year, and was obviously higher in non-growth season than in growth season.

  19. Streamwater Chemistry and Nutrient Export During Five Years of Bark Beetle Infestation of Subalpine Watersheds at the Fraser Experimental Forest

    Science.gov (United States)

    Rhoades, C.; Elder, K.; Hubbard, R.; Porth, L.

    2008-12-01

    Forested watersheds of western North America are currently undergoing rapid and extensive canopy mortality caused by a variety of insect species. The mountain pine bark beetle (Dendroctonus ponderosae) began to attack lodgepole pine (Pinus contorta) at the USFS Fraser Experimental Forest in central Colorado in 2002. By 2007, bark beetles had killed 78% of the overstory pine in Fraser research watersheds on average. The hydrologic, climatic, biogeochemical and vegetation records at the Fraser Experimental Forest provide a unique opportunity to quantify the impacts of this widespread, but poorly understood forest disturbance relative to a multi-decade pre-disturbance period. Here we compare seasonal streamwater chemistry and annual nutrient export for the five years since the bark beetle outbreak began with the pre- attack record. Patterns in post-outbreak streamwater biogeochemistry are compared to changes is species composition and proportional loss of overstory basal area for four basins. The influence of the outbreak will depend upon an aggregate of short (i.e. halted overstory water and nutrient use) and longer-term (i.e. altered canopy interception, windthrow, and understory growth) processes, so the hydrologic and biogeochemical implications of current beetle activity will not be fully realized for decades.

  20. Native red deer and introduced chamois: foraging habits and competition in a subalpine meadow-spruce forest area

    Czech Academy of Sciences Publication Activity Database

    Homolka, Miloslav; Heroldová, Marta

    2001-01-01

    Roč. 50, č. 2 (2001), s. 89-98 ISSN 0139-7893 R&D Projects: GA ČR GA206/97/0172; GA AV ČR KSK6005114 Institutional research plan: CEZ:AV0Z6093917 Keywords : Cervus elaphus * Rupicapra rupicapra * foraging strategy Subject RIV: EG - Zoology Impact factor: 0.287, year: 2001

  1. Drying-induced decomposition and associated changes in aggregation and carbon distribution in subalpine meadow soils: implication of drought

    Science.gov (United States)

    Berhe, A. A.; Arnold, C. L.; Ghezzehei, T. A.

    2016-12-01

    While peatlands are garnering much attention for their greenhouse gas feedback potential in a warming climate, the coupled biogeochemical and hydrological impact of structural and physical changes in these types of systems as a result of drought-induced drying and desiccation has not been studied in detail. The cyclic drawdown/recharge of the water table that exists in most peatland systems impose important controls on organic matter storage and decomposition as well as soil physical properties. In order to better understand how high elevation peatlands will respond to increasingly dry years, we incubated meadow soils collected along a hydrologic gradient at 5 different water potentials and measured the CO2 flux at intervals for over one year to determine how desiccation of meadow soils (from the Harvey Monroe Hall Research Natural Area at the crest of the Sierra Nevada) influences gaseous fluxes of C, as well as aggregation of the organic-rich soils and distribution of the soil C in different physical pools (macro- vs. micro-aggregate, and silt+ clay fractions). We found that the cumulative carbon mineralization was greatest at the highest (0.1 bar) and lowest (4 bar) water potential, across all regions of the meadow, indicating the presence of two separate pools of labile carbon that can be accessed only after a threshold of drying is reached in the soil. We also observe important changes associated with aggregate size distributions and fraction of total carbon distributed in three distinct pools.

  2. 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...

  3. A multi-scale evaluation of pack stock effects on subalpine meadow plant communities in the Sierra Nevada.

    Science.gov (United States)

    Lee, Steven R; Berlow, Eric L; Ostoja, Steven M; Brooks, Matthew L; Génin, Alexandre; Matchett, John R; Hart, Stephen C

    2017-01-01

    We evaluated the influence of pack stock (i.e., horse and mule) use on meadow plant communities in Sequoia and Yosemite National Parks in the Sierra Nevada of California. Meadows were sampled to account for inherent variability across multiple scales by: 1) controlling for among-meadow variability by using remotely sensed hydro-climatic and geospatial data to pair stock use meadows with similar non-stock (reference) sites, 2) accounting for within-meadow variation in the local hydrology using in-situ soil moisture readings, and 3) incorporating variation in stock use intensity by sampling across the entire available gradient of pack stock use. Increased cover of bare ground was detected only within "dry" meadow areas at the two most heavily used pack stock meadows (maximum animals per night per hectare). There was no difference in plant community composition for any level of soil moisture or pack stock use. Increased local-scale spatial variability in plant community composition (species dispersion) was detected in "wet" meadow areas at the two most heavily used meadows. These results suggest that at the meadow scale, plant communities are generally resistant to the contemporary levels of recreational pack stock use. However, finer-scale within-meadow responses such as increased bare ground or spatial variability in the plant community can be a function of local-scale hydrological conditions. Wilderness managers can improve monitoring of disturbance in Sierra Nevada meadows by adopting multiple plant community indices while simultaneously considering local moisture regimes.

  4. A multi-scale evaluation of pack stack effects on subalpine meadow plant communities in the Sierra Nevada

    Science.gov (United States)

    We evaluated the influence of pack stock (i.e., horse and mule) use on meadow plant communities in Sequoia and Yosemite National Parks in the Sierra Nevada mountains of California. Meadows were sampled to account for inherent variability across multiple scales by: 1) controlling for among-meadow var...

  5. Wild plant species growing closely connected in a subalpine meadow host distinct root-associated bacterial communities

    Directory of Open Access Journals (Sweden)

    Kristin Aleklett

    2015-02-01

    Full Text Available Plant roots are known to harbor large and diverse communities of bacteria. It has been suggested that plant identity can structure these root-associated communities, but few studies have specifically assessed how the composition of root microbiota varies within and between plant species growing under natural conditions. We assessed the community composition of endophytic and epiphytic bacteria through high throughput sequencing using 16S rDNA derived from root tissues collected from a population of a wild, clonal plant (Orange hawkweed–Pilosella aurantiaca as well as two neighboring plant species (Oxeye daisy–Leucanthemum vulgare and Alsike clover–Trifolium hybridum. Our first goal was to determine if plant species growing in close proximity, under similar environmental conditions, still hosted unique root microbiota. Our results showed that plants of different species host distinct bacterial communities in their roots. In terms of community composition, Betaproteobacteria (especially the family Oxalobacteraceae were found to dominate in the root microbiota of L. vulgare and T. hybridum samples, whereas the root microbiota of P. aurantiaca had a more heterogeneous distribution of bacterial abundances where Gammaproteobacteria and Acidobacteria occupied a larger portion of the community. We also explored the extent of individual variance within each plant species investigated, and found that in the plant species thought to have the least genetic variance among individuals (P. aurantiaca still hosted just as diverse microbial communities. Whether all plant species host their own distinct root microbiota and plants more closely related to each other share more similar bacterial communities still remains to be fully explored, but among the plants examined in this experiment there was no trend that the two species belonging to the same family shared more similarities in terms of bacterial community composition.

  6. Initial turnover rates of two standard wood substrates following land-use change in subalpine ecosystems in the Swiss Alps

    Science.gov (United States)

    Anita C. Risch; Martin F. Jurgensen; Deborah S. Page-Dumroese; Martin Schutz

    2013-01-01

    Forest cover has increased in mountainous areas of Europe over the past decades because of the abandonment of agricultural areas (land-use change). For this reason, understanding how land-use change affects carbon (C) source-sink strength is of great importance. However, most studies have assessed mountainous systems C stocks, and less is known about C turnover rates,...

  7. Genetic diversity, mating system, and conservation of a Mexican subalpine relict, Picea mexicana Martínez

    Science.gov (United States)

    F. Thomas Ledig; Paul D. Hodgskiss; Virginia Jacob-Cervantes

    2002-01-01

    Mexican spruce (Picea mexicana Martínez), an endangered species of the highest sky islands in México’s Sierra Madre Oriental and Sierra Madre Occidental, is threatened by fire, grazing, and global warming. Its conservation depends on whether it also is threatened by inbreeding and loss of genic diversity. We used 18 isozyme markers in 12 enzyme...

  8. Trait assembly of woody plants in communities across sub-alpine gradients: Identifying the role of limiting similarity

    NARCIS (Netherlands)

    Yan, B.; Zhang, J.; Liu, Y.; Li, Z.; Huang, X.; Yang, W.; Prinzing, A.

    2012-01-01

    Questions - Plant species can be assembled into communities through habitat filtering or species competition, but their relative roles are still debated. We do not know whether there is limited similarity between co-existing species when accounting for the parallel effect of abiotic habitat

  9. A multi-scale evaluation of pack stock effects on subalpine meadow plant communities in the Sierra Nevada

    Science.gov (United States)

    Lee, Steven R.; Berlow, Eric L.; Ostoja, Steven M.; Brooks, Matthew L.; Génin, Alexandre; Matchett, John R.; Hart, Stephen C.

    2017-01-01

    We evaluated the influence of pack stock (i.e., horse and mule) use on meadow plant communities in Sequoia and Yosemite National Parks in the Sierra Nevada of California. Meadows were sampled to account for inherent variability across multiple scales by: 1) controlling for among-meadow variability by using remotely sensed hydro-climatic and geospatial data to pair stock use meadows with similar non-stock (reference) sites, 2) accounting for within-meadow variation in the local hydrology using in-situ soil moisture readings, and 3) incorporating variation in stock use intensity by sampling across the entire available gradient of pack stock use. Increased cover of bare ground was detected only within “dry” meadow areas at the two most heavily used pack stock meadows (maximum animals per night per hectare). There was no difference in plant community composition for any level of soil moisture or pack stock use. Increased local-scale spatial variability in plant community composition (species dispersion) was detected in “wet” meadow areas at the two most heavily used meadows. These results suggest that at the meadow scale, plant communities are generally resistant to the contemporary levels of recreational pack stock use. However, finer-scale within-meadow responses such as increased bare ground or spatial variability in the plant community can be a function of local-scale hydrological conditions. Wilderness managers can improve monitoring of disturbance in Sierra Nevada meadows by adopting multiple plant community indices while simultaneously considering local moisture regimes.

  10. Abundance of Royle’s pika (Ochotona roylei along an altitudinal gradient in Uttarakhand, Western Himalaya

    Directory of Open Access Journals (Sweden)

    Sabuj Bhattacharyya

    2010-06-01

    Full Text Available Abstract The relative abundance of Royle’s pika (Ochotona roylei was studied in a part of the Kedarnath Wildlife Sanctuary, Uttarakhand, West Himalaya along an altitudinal gradient from 2900 to 3650 m a.s.l. Pikas’ detection probability and relative abundance per month and habitat were recorded by monthly surveys consisting of three sampling sessions of four hours each. Food plant species were identified by visual observation and quantified by a standard quadrat method. The highest relative abundance was observed at man-made walls and surroundings in the alpine zone and on broken slopes in the sub-alpine one, whereas alpine meadows showed the lowest abundance. A total of 26 plant species were found to be consumed by pikas. The proportion of forage plants was the highest (77.4% on the rocky slopes of the timberline zone The results of multiple regressions suggest that rock cover is the main factor affecting the relative abundance of Royle’s pika. Rocky areas probably offer both nest-sites and temporary refuges to escape from predators.
    Riassunto Abbondanza relativa del pica di Royle (Ochotona roylei lungo un gradiente altitudinale in Uttarakhand, Himalaya occidentale. In un’area del Kedarnath Wildlife Sanctuary (Uttarakhand, Himalaya occidentale, é stata stimata l’abbondanza relativa del pika di Royle (Ochotona roylei lungo un gradiente altitudinale compreso tra 2900 e 3650 m. Sono stati identificate tre fasce altitudinali e 10 habitat complessivi. La probabilità di osservazione e l’abbondanza relativa dei pika per ciascun mese e habitat sono state stimate tramite censimenti mensili consistenti in tre periodi di 4 ore ciascuno. Le specie vegetali consumate sono state identificate tramite osservazione diretta; la disponibilità è stata quantificata tramite rilievo fitosociologico standard. L’abbondanza relativa maggiore è stata riscontrata nella

  11. Relaciones entre la zonalidad petrológica y metalogénica de los macizos lerzolíticos de las cadenas alpinas del Mediterráneo Occidental (Cordillera Bético-Rifeña y Kabylias

    Directory of Open Access Journals (Sweden)

    Torres-Ruiz, J.

    1988-12-01

    Full Text Available Gamet-lherzolite facies, Ariegite and Seiland subfacies of the spinel-lherzolite facies and plagioclase-lherzolite facies have been identified in the Serranía de Ronda, Beni Bousera and Collo lherzolitic massifs. These petrological facies occur in a zonal arrangement: gamet lherzolite are in contact with the overlaying metapelitic sequence and spinel then plagioclase lherzolite occur inwards, representing the innermost zones in the former mantle body. The various occurrences of mineralizations can be classified in two main groups: one of them is essentialIy made up of chromite and Ni arsenides with pyroxene and/or cordierite as gangue minerals; the other consists Qf Fe-Ni-Cu sulfides and graphite, with pyroxene, plagioclase and phlogopite as gangue minerals. In both groups, the ores with the more refractory composition were the first to crystallize in the hotter core of the diapir while those other with a more differentiated composition were formed later within the external zones. The close correlation between petrological and metallogenical roning supports a magmatic origin of the mineralizations related to the petrologic evolution of the mantle bodies. The mineralizing liquids• originated from magmas generated by partial melting of the peridotites. The former migrated outwards, from the internal part of the bodies, during which marked interaction with the enclosing rocks and complex fractionation processes took place under moderate to low pressure conditions.En los macizos lerzolíticos de la Serranía de Ronda, de Beni Bousera y de Collo se han identificado facies de lerzolitas con granate, facies de lerzolitas con espinela (subfacies Ariegita y Seiland y facies de lerzolitas con plagioclasa. Estas facies petrológicas se distribuyen de forma que las lerzolitas con granate se sitúan en contacto con la unidad metapelítica suprayacente, mientras que las lerzolitas con espinela y con plagioclasa lo hacen en posiciones progresivamente más alejadas, representando zonas cada vez más internas en el primitivo cuerpo ultramáfico. Los diferentes indicios de mineralización pueden dividirse en dos grupos: uno compuesto esencialmente por cromita y arseniuros de níquel con ganga de piroxenos y/o cordierita, y el otro constituido por sulfuros de Fe-Ni-Cu con grafito y con piroxenos, plagioclasa y flogopita como minerales de la ganga. En ambos grupos las mineralizaciones de composición más refractaria son las primeras en cristalizar y lo hacen en las etapas más tempranas en las zonas más internas del diapiro, mientras que las de composición más diferenciada lo hacen más tarde en posiciones más periféricas. La fuerte interrelación entre la zonación petrológica y metalogénica apoya una génesis para las mineralizaciones íntimamente asociada a la evolución petrológica de los diapiros del manto. Los líquidos mineralizantes derivan de magmas generados mediante la fusión parcial de las peridotitas y habrían migrado hacia la periferia sufriendo un complejo proceso de fraccionación e interacción con las rocas encajantes, en condiciones de presión moderadas a bajas.

  12. GENETIC DIVERSITY BETWEEN THREE SPECIES OF SANGUISORBA L. FROM WEST SIBERIA BASED ON RANDOMLY AMPLIFIED DNA FINGERPRI

    Directory of Open Access Journals (Sweden)

    M. G. Kutsev

    2015-04-01

    Full Text Available Genetic differences between Sanguisorba officinalis L., S. alpina Bunge and S. azovtsevii Krasnob. et Pschen. were studied. Randomly amplified DNA fingerprints (RAF technique demonstrated a high degree of genetic identity between S. alpina and S. azovtsevii. Placement of S. officinalis and S. azovtsevii into the same species is shown to be unjustified. Allopolyploid origin of S. azovtsevii on the basis of S. alpina genome with a small contribution of S. officinalis is confirmed.

  13. Diversity of winter photoinhibitory responses: a case study in co-occurring lichens, mosses, herbs and woody plants from subalpine environments.

    Science.gov (United States)

    Míguez, Fátima; Fernández-Marín, Beatriz; Becerril, José-María; García-Plazaola, José-Ignacio

    2017-07-01

    Winter evergreens living in mountainous areas have to withstand a harsh combination of high light levels and low temperatures in wintertime. In response, evergreens can activate a photoprotective process that consists of the downregulation of photosynthetic efficiency, referred to as winter photoinhibition (WPI). WPI has been studied mainly in woody evergreens and crops even when, in many instances, other functional groups such as lichens or bryophytes dominate in alpine and boreal habitats. Thus, we aimed to (1) assess the occurrence of WPI within overwintering evergreens comprising woody species, herbs, mosses and lichens, (2) compare the recovery kinetics among those groups and (3) clarify the role of thylakoid proteins and pigments in both processes: WPI and recovery. With this aim, WPI was analyzed in 50 species in the field and recovery kineticcs were studied in one model species from each functional group. Results showed that high levels of WPI are much more frequent among woody plants than in any other group, but are also present in some herbs, lichens and mosses. Winter conditions almost always led to the de-epoxidation of the xanthophyll cycle. Nevertheless, changes in the de-epoxidation level were not associated with the activation/deactivation of WPI in the field and did not match changes in photochemical efficiency during recovery treatments. Seasonal changes in thylakoid proteins [mainly D1 (photosystem II core complex protein) and PsbS (essential protein for thermal dissipation)] were dependent on the functional group. The results highlight the diversity of physiological solutions and suggest a physical-mechanical reason for the more conservative strategy of woody species compared with other groups. © 2017 Scandinavian Plant Physiology Society.

  14. Ecology of whitebark pine populations in relation to white pine blister rust infection in subalpine forests of the Lake Tahoe Basin: Implications for restoration

    Science.gov (United States)

    Patricia E. Maloney; Detlev R. Vogler; Camille E. Jensen; Annette. Delfino Mix

    2012-01-01

    For over a century, white pine blister rust (WPBR), caused by the introduced fungal pathogen, Cronartium ribicola J.C. Fisch., has affected white pine (Subgenus Strobus) individuals, populations, and associated forest communities in North America. We surveyed eight populations of whitebark pine (Pinus albicaulis Engelm.) across a range of environmental conditions in...

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

    Science.gov (United States)

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

    2016-12-01

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

  16. Beyond random and forbidden interactions : how optimizing energy gain results in morphological matching among subalpine Asteraceae and their flower-visitors

    NARCIS (Netherlands)

    Klumpers, S.G.T.

    2017-01-01

    Plants and their pollinators form complex interaction networks. Within these networks, species differ widely in the number of species they interact with. These interaction patterns are important aspects in pollination ecology, since it influences species coexistence and community stability.

  17. The effect of past fire activity on soil erosional processes in two subalpine sediment records from Rodna Mountains, Northern Romanian Carpathians

    Directory of Open Access Journals (Sweden)

    Aritina HALIUC

    2014-11-01

    Full Text Available Fire is an important disturbance factor across a variety of vegetation zones and one of the major causes of geomorphological and ecological changes (Shakesby&Doerr, 2006. In the context of current and anticipated climate change, fire severity and frequency is expected to increase. The impact of fire in shaping the physical, chemical, biological characteristics of a soil surface is mediated by the interaction between climate factors, vegetation attributes and human activities. Depending on the size, duration and temperature reached, fire usually consumes the litter and vegetation cover. It consequently changes soil stability by enhancing rain-splash detachment, modifying infiltration and promoting soil erosion. Nonetheless, the long-term geomorphological effects of fire activity revealed by lake sediment records have been sparsely investigated in terms of both geographical coverage and range of environmental characteristics. Therefore, a better understanding of fire activity in a future warmer climate will be crucial in assessing and predicting landscape dynamics, feedback mechanisms and sensitivity to soil erosion with different fire behaviour. 

  18. Air quality at a snowmobile staging area and snow chemistry on and off trail in a Rocky Mountain subalpine forest, Snowy Range, Wyoming.

    Science.gov (United States)

    Musselman, Robert C; Korfmacher, John L

    2007-10-01

    A study was begun in the winter of 2000-2001 and continued through the winter of 2001-2002 to examine air quality at the Green Rock snowmobile staging area at 2,985 m elevation in the Snowy Range of Wyoming. The study was designed to evaluate the effects of winter recreation snowmobile activity on air quality at this high elevation site by measuring levels of nitrogen oxides (NO( x ), NO), carbon monoxide (CO), ozone (O(3)) and particulate matter (PM(10) mass). Snowmobile numbers were higher weekends than weekdays, but numbers were difficult to quantify with an infrared sensor. Nitrogen oxides and carbon monoxide were significantly higher weekends than weekdays. Ozone and particulate matter were not significantly different during the weekend compared to weekdays. Air quality data during the summer was also compared to the winter data. Carbon monoxide levels at the site were significantly higher during the winter than during the summer. Nitrogen oxides and particulates were significantly higher during the summer compared to winter. Nevertheless, air pollutants were well dispersed and diluted by strong winds common at the site, and it appears that snowmobile emissions did not have a significant impact on air quality at this high elevation ecosystem. Pollutant concentrations were generally low both winter and summer. In a separate study, water chemistry and snow density were measured from snow samples collected on and adjacent to a snowmobile trail. Snow on the trail was significantly denser and significantly more acidic with significantly higher concentrations of sodium, ammonium, calcium, magnesium, fluoride, and sulfate than in snow off the trail. Snowmobile activity had no effect on nitrate levels in snow.

  19. Time since death and decay rate constants of Norway spruce and European larch deadwood in subalpine forests determined using dendrochronology and radiocarbon dating

    Science.gov (United States)

    Petrillo, Marta; Cherubini, Paolo; Fravolini, Giulia; Marchetti, Marco; Ascher-Jenull, Judith; Schärer, Michael; Synal, Hans-Arno; Bertoldi, Daniela; Camin, Federica; Larcher, Roberto; Egli, Markus

    2016-03-01

    Due to the large size (e.g. sections of tree trunks) and highly heterogeneous spatial distribution of deadwood, the timescales involved in the coarse woody debris (CWD) decay of Picea abies (L.) Karst. and Larix decidua Mill. in Alpine forests are largely unknown. We investigated the CWD decay dynamics in an Alpine valley in Italy using the chronosequence approach and the five-decay class system that is based on a macromorphological assessment. For the decay classes 1-3, most of the dendrochronological samples were cross-dated to assess the time that had elapsed since tree death, but for decay classes 4 and 5 (poorly preserved tree rings) radiocarbon dating was used. In addition, density, cellulose, and lignin data were measured for the dated CWD. The decay rate constants for spruce and larch were estimated on the basis of the density loss using a single negative exponential model, a regression approach, and the stage-based matrix model. In the decay classes 1-3, the ages of the CWD were similar and varied between 1 and 54 years for spruce and 3 and 40 years for larch, with no significant differences between the classes; classes 1-3 are therefore not indicative of deadwood age. This seems to be due to a time lag between the death of a standing tree and its contact with the soil. We found distinct tree-species-specific differences in decay classes 4 and 5, with larch CWD reaching an average age of 210 years in class 5 and spruce only 77 years. The mean CWD rate constants were estimated to be in the range 0.018 to 0.022 y-1 for spruce and to about 0.012 y-1 for larch. Snapshot sampling (chronosequences) may overestimate the age and mean residence time of CWD. No sampling bias was, however, detectable using the stage-based matrix model. Cellulose and lignin time trends could be derived on the basis of the ages of the CWD. The half-lives for cellulose were 21 years for spruce and 50 years for larch. The half-life of lignin is considerably higher and may be more than 100 years in larch CWD. Consequently, the decay of Picea abies and Larix decidua is very low. Several uncertainties, however, remain: 14C dating of CWD from decay classes 4 and 5 and having a pre-bomb age is often difficult (large age range due to methodological constraints) and fall rates of both European larch and Norway spruce are missing.

  20. Artificial 137Cs and natural 40K in mushrooms from the subalpine region of the Minya Konka summit and Yunnan Province in China.

    Science.gov (United States)

    Falandysz, Jerzy; Saniewski, Michał; Zhang, Ji; Zalewska, Tamara; Liu, Hong-Gao; Kluza, Karolina

    2018-01-01

    A study on 137Cs pollution and activity concentrations of 40K in mushrooms of the genera Cortinarius, Leccinum, Russula, Tricholoma, Tylopilus, and Xerocomus from two neighboring regions in southwest China in 2010-2013 revealed different patterns of pollution with 137Cs, which seemed to be highly dependent on climate conditions. Tricholoma matsutake was collected in Yunnan before and after the Fukushima Dai-ichi nuclear accident and showed similar contamination with 137Cs. Mushrooms from the elevation of 2800-3480 m above sea level on the east slope of Minya Konka and forest topsoil showed higher contamination with 137Cs than mushrooms from the highlands of Yunnan. In detail, the activity concentration of 137Cs in caps of mushrooms from Minya Konka were in the range 62 ± 6-280 ± 150 Bq kg-1 dry biomass and from Yunnan at climate in the region of the Minya Konka is much colder than in Yunnan, which seems to favor deposition of 137Cs at higher altitudes from global atmospheric circulation. The activity concentration of 40K in mushrooms and soils highly exceeded that of 137Cs. The assessed annual effective doses for 137Cs in 1 kg of consumed mushrooms of the genera Leccinum and Xerocomus in Yunnan were low, i.e., in the range < 0.0043-0.049 ± 0.004 μSv, while those for 40K were 0.26 ± 0.02-0.81 ± 0.09 μSv.

  1. A Bayesian Analysis Shows That a Spruce Beetle Outbreak Reduces Snow Interception and Sublimation in a Subalpine Spruce-Fir Forest

    Science.gov (United States)

    Frank, J. M.; Massman, W. J.; Ewers, B. E.; Williams, D. G.

    2016-12-01

    Sublimation is a key component in the water cycle of cold, snow dominated ecosystems. In many high elevation spruce-fir forests of western North America, recent spruce beetle outbreaks have caused widespread tree mortality, opened the canopy, and potentially altered the processes that control sublimation. This study evaluates three hypotheses: in these ecosystems the dominant source for sublimation originates from canopy intercepted snow, the loss of canopy following a beetle disturbance leads to significantly less sublimation, and major sublimation events are driven by the flow of sensible heat into the canopy. Bayesian analysis is used to evaluate a two source energy and canopy mass model that explains seventeen years (2000-2016) of winter eddy-covariance flux data at the GLEES AmeriFlux sites where a spruce beetle outbreak caused 75-85% basal area mortality. The model estimated that the resistance to snow sublimation from the canopy was an order of magnitude less than from the snowpack and that the maximum snow loading in the canopy was reduced to 25-56% of its pre-outbreak capacity. Comparing model results obtained using the observed decrease in leaf area index versus a "no beetle" condition, there has been a significant decrease in ecosystem sublimation since 2011. In the past few years, a 5-11% increase in snowpack sublimation has been offset by 28-32% less sublimation from canopy intercepted snow, with the net being 17-25% less total sublimation. This is equivalent to 3-6% of the total precipitation. Informing the model with information other than the above-canopy fluxes indicates that a near snowpack eddy covariance system decreases the canopy contribution to sublimation, including observed sensible heat fluxes requires a correction to resolve the surface energy imbalance, and stable isotopes of water vapor extend sublimation events. Because tree growth and ecological succession are slow in spruce-fir forests, these results could persist for decades.

  2. AcEST: DK953800 [AcEST

    Lifescience Database Archive (English)

    Full Text Available rbita pepo GN=CA... 317 3e-86 sp|O24339|CATA_SOLAP Catalase OS=Soldanella alpina ...QTRIFSYA 349 >sp|O24339|CATA_SOLAP Catalase OS=Soldanella alpina PE=2 SV=1 Length = 492 Score = 315 bits (80

  3. AcEST: DK951372 [AcEST

    Lifescience Database Archive (English)

    Full Text Available 91 e-108 sp|O24339|CATA_SOLAP Catalase OS=Soldanella alpina PE=2 SV=1 389 e-108 sp|P25819|CATA2_ARATH Catala... Sbjct: 181 ESLHMFSFLFDDLGVP 196 >sp|O24339|CATA_SOLAP Catalase OS=Soldanella alpina PE=2 SV=1 Length = 492

  4. NCBI nr-aa BLAST: CBRC-DDIS-05-0061 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-DDIS-05-0061 dbj|BAA75927.1| delta-9 fatty acid desaturase [Mortierella alpina...] dbj|BAA75928.1| delta-9 fatty acid desaturase [Mortierella alpina] BAA75927.1 1e-107 48% ...

  5. Only Ex-Offenders Need Apply. The Ohio Parole Officer Aide Program. An Exemplary Project.

    Science.gov (United States)

    1976

    The Parole Officer Aide Program of Ohio employs qualified ex-offenders as Parole Officer Aides (POA). The POA is given on-the-job training for six months and assumes the identical tasks as parole officers with the exception of signing parole violation reports. The POA's background and familiarity with local situations gives him the ability to…

  6. Population dynamics along a primary succession gradient: do alpine species fit into demographic succession theory?

    Science.gov (United States)

    Marcante, Silvia; Winkler, Eckart; Erschbamer, Brigitta

    2009-05-01

    Understanding processes and mechanisms governing changes in plant species along primary successions has been of major importance in ecology. However, to date hardly any studies have focused on the complete life cycle of species along a successional gradient, comparing pioneer, early and late-successional species. In this study it is hypothesized that pioneer species should initially have a population growth rate, lambda, greater than one with high fecundity rates, and declining growth rates when they are replaced by late-successional species. Populations of late-successional species should also start, at the mid-successional stage (when pioneer species are declining), with growth rates greater than one and arrive at rates equal to one at the late successional stage, mainly due to higher survival rates that allow these species to persist for a long time. The demography of pioneer- (Saxifraga aizoides), early (Artemisia genipi) and late-successional species (Anthyllis vulneraria ssp. alpicola) was investigated together with that of a ubiquitous species (Poa alpina) along the Rotmoos glacier foreland (2300-2400 m a.s.l., Central Alps, Austria) over 3 years. A matrix modelling approach was used to compare the main demographic parameters. Elasticity values were plotted in a demographic triangle using fecundity, individual growth and survival as vital rates contributing to the population growth rates. The results largely confirmed the predictions for population growth rates during succession. However, high survival rates of larger adults characterized all species, regardless of where they were growing along the succession. At the pioneer site, high mortality rates of seedlings, plantlets and young individuals were recorded. Fecundity was found to be of minor relevance everywhere, but it was nevertheless sufficient to increase or maintain the population sizes. Demographically, all the species over all sites behaved like late-successional or climax species in secondary

  7. Using Measured Plane-of-Array Data Directly in Photovoltaic Modeling: Methodology and Validation: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, Janine; Freestate, David; Riley, Cameron; Hobbs, William

    2016-11-01

    Measured plane-of-array (POA) irradiance may provide a lower-cost alternative to standard irradiance component data for photovoltaic (PV) system performance modeling without loss of accuracy. Previous work has shown that transposition models typically used by PV models to calculate POA irradiance from horizontal data introduce error into the POA irradiance estimates, and that measured POA data can correlate better to measured performance data. However, popular PV modeling tools historically have not directly used input POA data. This paper introduces a new capability in NREL's System Advisor Model (SAM) to directly use POA data in PV modeling, and compares SAM results from both POA irradiance and irradiance components inputs against measured performance data for eight operating PV systems.

  8. Alimentazione di Marmota marmota in praterie altimontane delle dolomiti bellunesi

    Directory of Open Access Journals (Sweden)

    Alessandro Rudatis

    2006-03-01

    Full Text Available Abstract The diet of Marmota marmota in the mountain prairie of south-eastern Italian Alps. Diet composition of two family groups of alpine marmots was investigated in two areas of the Agordino’s Dolomites (Italian Alps in June-September 2001, by means of microscopic analysis of faeces and of direct observation of feeding activity. During the whole period of activity, a high consume of Angiosperms was confirmed, especially plants in flower; among them the “graminoids” seemed to play an important role only during the initial part of the active period. Generally vegetative parts predominated over flowers. The ingestion of animal preys was not confirmed by the analysis of droppings. Comparing diet composition of the two groups, Graminaceae (Poa, Phleum, Compositae (Achillea, Cyperaceae/Juncaceae, Leguminosae (Anthyllis, Rosaceae, and Labiatae (Prunella, Stachys formed the bulk of marmot diet in the study areas. Diet showed low diversity considering the abundance of plant species in the surrounding environment. Food resources were probably used in relation to their easy digestibility, with a high content in proteins, sugar and water. The knowledge of vegetation features in relation to marmot trophic habits can represent a useful tool for the management of this species. Riassunto Il regime alimentare di due gruppi di Marmotta alpina è stato studiato in giugno-settembre 2001 in due aree delle Dolomiti agordine (SE Italia, attraverso l’analisi microscopica delle feci e l’osservazione diretta dell’attività alimentare. Durante tutto il periodo di attività si è notato un forte consumo di Angiosperme, specialmente piante a fiore, mentre le ”graminoidi” sembra giochino un ruolo importante all’inizio della stagione. In generale le parti vegetali predominano sui fiori. L’ingestione di prede animali non è stata

  9. Molecular systematics of the parasitic genus Conopholis (Orobanchaceae) inferred from plastid and nuclear sequences

    National Research Council Canada - National Science Library

    Anuar G. Rodrigues; Alison E.L. Colwell; Saša Stefanović

    2011-01-01

    .... Presently, Conopholis is described as having two species, C. americana and C. alpina. This classification is based on a combination of presence/absence of morphological characters along with a number of quantitative traits...

  10. SINET

    African Journals Online (AJOL)

    Mikaniopsis clematoidcs, Galiniera saxifraga. Nuxia congesta are the other common species in this community type. The herbaceous layer includes. Swertia kilimandiscliarii, Thymus schimperii, Carduus chamaecephalus, C, nyassanus Stachys alpina,. Trifolium burclzeliana, T. simense and Cynog'lossum coeruleum.

  11. Effects of fetal brain grafting on adult behavioral masculinization and defeminization in neonatally androgenized female rats.

    Science.gov (United States)

    Tsai, Y F; Chen, T J; Pi, W P; Tai, M Y; Huang, R L; Chiueh, C C; Peng, M T

    1995-05-05

    Treatment of neonatal female rats with androgen results not only in decreased female sexual behavior but also in enhanced male sexual behavior examined in adulthood. The effects of grafting fetal preoptic area (POA) neurons into the POA, and fetal hypothalamic (HPT) neurons into the ventromedial hypothalamus (VMH), were tested in neonatally androgen-sterilized rats (ASR). The rats were injected subcutaneously with 80 micrograms testosterone propionate within the 24 hours after birth to see if sexual behavior could be normalized by fetal brain grafts. In repeated tests on ASR grafted with fetal HPT into the VMH, the lordotic response was seen to increase to the level seen in non-ASR controls, while the increase in mounting behavior in ASR was suppressed following grafting of fetal POA or cerebral cortex into the POA. These results suggest that there are dysfunctions of POA and VMH in ASR, and that the dysfunctions revealed by sexual behavior can be overcome by fetal POA or HPT grafting.

  12. Dehydroepiandrosterone as an adjunct to gonadotropins in infertile Indian women with premature ovarian aging: A pilot study

    OpenAIRE

    Nisha Malik; Alka Kriplani; Nutan Agarwal; Neerja Bhatla; Garima Kachhawa; Raj Kumar Yadav

    2015-01-01

    BACKGROUND: Dehydroepiandrosterone (DHEA) supplementation is a relatively recent development that augments ovarian responsiveness in patients with poor ovarian reserve and premature ovarian aging (POA). AIMS: To evaluate the efficacy of DHEA supplementation prior to gonadotropins for ovulation induction in women with POA. DESIGN: Prospective randomized controlled study. METHODS: Fifty infertile women with POA were randomized into two groups of 25 each. Group 1 received tablet DHEA 25 mg while...

  13. Environmental Impact Study of The Northern Section of the Upper Mississippi River, Minnesota River Pool.

    Science.gov (United States)

    1973-11-01

    COMPOSITAE (Continued) IGrindelia qurrs Curlycup-gumweed Helianthus occidentczlisI Wes tern sunflower Heli- anthus petiolarus Petioled sunflower P He iopsis he...dichotomiftorm Spreading witch grass P Pania= virgatwn Switch grass P Phalaris arundinacea Canary grass Poa palustris Fowl meadow-grass P Poa pratensis Blue grass...Herbs Yellow jewelweed. Impatiens pillida Kentucky bluegrass Poa Nettle Urtica procera pratensis Sweet cicely 03z:ohiza sp. I A-44 Table 3. Vegetation of

  14. Análisis de la estructura alpina de la corteza del centro de la Península Ibérica: Una sección Magneto-Telúrica a través del Sistema Central (Sierra de Gredos)

    OpenAIRE

    Pous, Jaume; Muñoz Martín, Alfonso; Olaiz Campos, Antonio José; Seillé, H.; Vicente Muñoz, Gerardo de

    2012-01-01

    We present a magnetotelluric profile across the Duero basin, the Central System and the Madrid basin, acquired in the framework of the TOPO-IBERIA project. The MT profile consists of 24 magnetotelluric sites over a 200 km, NS oriented profile. Five components were measured with periods ranging from 0.001 s to 500s. The dimensional analysis reveals a dominant E-W direction and 2D joint inversion of apparent resistivity, phases and tipper was carried out. The inverse resistivity model obtained ...

  15. Efeitos do estresse térmico nas concentrações plasmáticas de progesterona (P4 e estradiol 17-b (E2 e temperatura retal em cabras da raça Pardo Alpina Effects of heat stress on progesterone (P4 and estradiol-17b plasma concentrations and rectal temperature of Alpine Brown goats

    Directory of Open Access Journals (Sweden)

    Luis Fernando Uribe-Velásquez

    2001-04-01

    Full Text Available Seis cabras lactantes foram distribuídas aleatoriamente em um delineamento experimental em "crossover", em dois grupos: sob condições termoneutras e estresse térmico. Um período de adaptação de 28 dias foi seguido por quatro períodos de 14 dias cada, quando os animais sob estresse térmico foram expostos à temperatura média de 33,84ºC; THI de 86,20; BGT de 36,18 e BT de 32,11ºC das 8 às 17 horas, incluindo radiação solar simulada das 10 às 15 horas. Não houve diferença entre as concentrações plasmáticas de progesterona, mas as fêmeas submetidas ao estresse térmico apresentaram diminuição nas concentrações plasmáticas de estradiol, quando comparados ao grupo termoneutro. A temperatura retal dos animais sob estresse térmico foi mais elevada quando foi comparada à do grupo de animais em condições de termoneutralidade. As cabras mantiveram as concentrações plasmáticas da progesterona, com diminuição na secreção de estradiol, quando expostas a um estresse repetido e intermitente, a despeito de ocorrer hipertermia durante o estresse pelo calor.Six lactating goats were randomly assigned to a crossover experimental design in two groups, under thermoneutral and heat stress conditions. An adaptation period of 28 days were followed by 4-periods of 14 days each, when the animals under heat stress were exposed to an average temperature of 33.34ºC; THI of 86.20; BGT of 36.18 and BT of 32.11ºC from 8 to 17 hours, including simulated solar radiation from 10 to 15 hours. There was no difference for progesterone plasma concentrations but the animals under heat stress showed a reduction of estradiol plasma concentrations as compared to the thermoneutral group. The rectal temperature of the animals under heat stress was higher when compared to the animals under thermoneutral conditions. The goats maintained progesterone plasma concentrations with reduction of estradiol secretion when exposed to repeat stress and intermittent in spite of the occurrence of hyperthermia during heat stress.

  16. Damage by Neonectria neomacrospora and Adelges piceae in provenance trials of subalpine fir (Abies lasiocarpa) in Denmark

    DEFF Research Database (Denmark)

    Skúlason, Brynjar; Hansen, Ole Kim; Thomsen, Iben Margrete

    2017-01-01

    Field trials of Abies lasiocarpa were undertaken with the aim of assessing the potential for Christmas tree production in Denmark. Twenty-six provenances originating from Alaska to New Mexico were tested. Damage by the insect Adelges piceae and the fungus Neonectria neomacrospora was recorded for...

  17. Erosion rates on subalpine paleosurfaces in the western Mediterranean by in-situ 10Be concentrations in granites: implications for surface processes and long-term landscape evolution in Corsica (France)

    NARCIS (Netherlands)

    Kuhlemann, J.; van der Borg, K.|info:eu-repo/dai/nl/067895298; Bons, P.D.; Danišík, M.; Frisch, W.

    2008-01-01

    A study of erosion rates by in-situ 10Be concentrations in granites of Miocene high-elevation paleosurfaces in Corsica indicates maximum erosion rates between 8 and 24 mm/kyear. The regional distribution of measured erosion rates indicates that the local climatic conditions, namely precipitation,

  18. Chemical characteristics and trophic condition of deep subalpine lake Garda during the spring overturn in 1999; Caratteristiche chimiche e situazione trofica del Lago di Garda nel corso dell'episodio di mescolamento delle acque della primavera del 1999

    Energy Technology Data Exchange (ETDEWEB)

    Salmaso, N.; Cordella, P. [Padua Univ., Padua (Italy). Dipt. di Biologia; Decet, F. [ARPAV, Belluno (Italy); Consolaro, P. [ARPAV, Verona (Italy)

    1999-12-01

    This paper reports the main results obtained from studies carried out during the spring overturn observed in 1999 in the largest Italian lake. The circulation documented has caused a complete oxygenation and homogenisation of the whole water column. The mixing seems to have had origin from convective motions, associated to a penetration of superficial colder waters below 270 m. [Italian] Questo lavoro riporta i risultati delle ricerche condotte nel corso dell'episodio di mescolamento delle acque del Lago di Garda della primavera del 1999, che ha determinato una completa riossiginezaione e omogeneizzazione dell'intera colonna d'acqua, probabilmente originata non solamente da moti convettivi, ma anche da una penetrazione di acque superficiali piu' fredde al di sotto dei 270 m. di profondita'.

  19. The Frequency of Growing Season Frost in the Subalpine Environment (Medicine Bow Mountains, Southeastern Wyoming), The Interaction of Leaf Morphology and Infrared Radiational Cooling and the Effects of Freezing on Native Vegetation

    Science.gov (United States)

    1995-05-01

    majority of chilling stress studies have focused on crop plants of tropical or subtropical origin (Öquist and Wass 1988; Peeler and Naylor 1988...light energy. Plant Physiol 84:218-224 Eastham J and Rose CW 1988. Pasture evapotranspiration under varying tree planting density in an agroforestry ...fluorescence and photoinhibition in a tropical rainforest understory plant. Photosyn Res 27:135-142 Leuning R 1988. Leaf temperatures during radiation

  20. Evidence of compounded disturbance effects on vegetation recovery following high-severity wildfire and spruce beetle outbreak

    National Research Council Canada - National Science Library

    Amanda R Carlson; Jason S Sibold; Timothy J Assal; Jose F Negrón

    2017-01-01

    Spruce beetle (Dendroctonus rufipennis) outbreaks are rapidly spreading throughout subalpine forests of the Rocky Mountains, raising concerns that altered fuel structures may increase the ecological severity of wildfire...

  1. Addition of methionine and low cultivation temperatures increase palmitoleic acid production by engineered Saccharomyces cerevisiae.

    Science.gov (United States)

    Kamisaka, Yasushi; Kimura, Kazuyoshi; Uemura, Hiroshi; Yamaoka, Masakazu

    2015-01-01

    Palmitoleic acid (POA) has recently gained attention for its health benefits and as a potential resource for industrial feedstock. This study focused on the use of Saccharomyces cerevisiae, which has a high POA content but low lipid content, for POA production. We created an oleaginous S. cerevisiae as a dga1 mutant overexpressing Dga1p lacking the N-terminal 29 amino acids (Dga1∆Np). This was performed to further increase POA content in the oleaginous S. cerevisiae through optimization of culture conditions and genetic modifications. We found that high concentrations of methionine (2.0 g/l) increased POA production in a concentration-dependent way, while other amino acids such as cysteine, glycine, and glutamine showed no effect. It was not clear if the effect of methionine was mediated through S-adenosylmethionine, mainly because its addition did not increase POA content as did the addition of methionine. We increased POA content up to 55% by incubation of the dga1 transformant in a medium containing 2 g/l methionine at lower than normal temperatures ranging from 20 to 25 °C. Cultivation at such temperatures increased dry cell weight, but did not affect the lipid content, thereby increasing total POA production. The effects of methionine and low temperatures (20-25 °C) on POA content were more apparent in the strains overexpressing Dga1∆Np than those harboring empty vectors, which was consistent with the observation that POA was enriched in triacylglycerol. Overexpression of Ole1p, the enzyme responsible for POA production, did not increase POA content of the dga1 mutant overexpressing Dga1∆Np, but increased that of the wild-type strain overexpressing Dga1∆Np. The results suggested that genomic Ole1p in the dga1 mutant was active enough to achieve the optimal POA production under these conditions. Finally, the POA production by the S. cerevisiae transformant was increased 2.5-fold, which demonstrates that oleaginous S. cerevisiae is a potential source

  2. Effectiveness and costeffectiveness of screening immigrants ...

    African Journals Online (AJOL)

    One cost effectiveness analysis was found that compared the costs of; active PoA screening, general practice screening and homeless screening groups. The cost of detecting a case of TB were; £1.26, £13.17and £96.36 for PS, homeless screening and active PoA screening respectively. The cost of preventing a case of TB ...

  3. Effectiveness and costeffectiveness of screening immigrants ...

    African Journals Online (AJOL)

    veloped countries include; 1) Screening immigrants at ports of entry referred to as “Port of Arrival Screening” (PoA) and. 2) Passive ... Objective: Evaluate efficiency of active PoA TB screening for immigrants from TB endemic-regions compared with Passive Screening ..... Tuberculosis crosses borders. In- ternational journal ...

  4. Preoptic inputs and mechanisms that regulate maternal responsiveness.

    Science.gov (United States)

    Dobolyi, A; Grattan, D R; Stolzenberg, D S

    2014-10-01

    The preoptic area is a well-established centre for the control of maternal behaviour. An intact medial preoptic area (mPOA) is required for maternal responsiveness because lesion of the area abolishes maternal behaviours. Although hormonal changes in the peripartum period contribute to the initiation of maternal responsiveness, inputs from pups are required for its maintenance. Neurones are activated in different parts of the mPOA in response to pup exposure. In the present review, we summarise the potential inputs to the mPOA of rodent dams from the litter that can activate mPOA neurones. The roles of potential indirect effects through increased prolactin levels, as well as neuronal inputs to the preoptic area, are described. Recent results on the pathway mediating the effects of suckling to the mPOA suggest that neurones containing the neuropeptide tuberoinfundibular peptide of 39 residues in the posterior thalamus are candidates for conveying the suckling information to the mPOA. Although the molecular mechanism through which these inputs alter mPOA neurones to support the maintenance of maternal responding is not yet known, altered gene expression is a likely candidate. Here, we summarise gene expression changes in the mPOA that have been linked to maternal behaviour and explore the idea that chromatin remodelling during mother-infant interactions mediates the long-term alterations in gene expression that sustain maternal responding. © 2014 British Society for Neuroendocrinology.

  5. Annual grasses in crop rotations with grass seed production - A survey with special focus on Vulpia spp. in red fescue production

    DEFF Research Database (Denmark)

    Jensen, Peter Kryger; Kristensen, Kristian

    2013-01-01

    in the field. The survey showed that Poa annua, Elytrigia repens and Poa trivialis were the three most frequent grass weeds in grass seed crops. Furthermore, Bromus hordeaceus, Bromus sterilis, P. trivialis and Vulpia spp. showed an increasing frequency in the study period. The perennial weed, E. repens...

  6. Rend Lake, Illinois (Operation and Maintenance).

    Science.gov (United States)

    1976-12-01

    Canada Poa compressa Bluegrass, Kentucky Poa pratensis Brachyelytrum Brachyelytrum spP. Brome-Grass Bromus spp. Broom-sedge Andropogon virginicus...Polioptila caerulea %Golden-crowned Kinglet Reuus satrapa Ruby-crowned Kinglet Reuus calendu ~a Water Pipit Anthus spinoletta **Cedar Waxwing Bombycilla

  7. Environmental Assessment Addressing the Integrated Control of Nuisance Species at Grand Forks Air Force Base, North Dakota

    Science.gov (United States)

    2013-04-01

    which included two introduced grass species, smooth bromegrass (Bromus inermis) and Kentucky blue grass (Poa pratensis ). These two introduced...and wetland habitat would be similar to that described for the Mekinock Prairie Chicken WMA. Additionally, the Sprague’s pipit ( Anthus spragueii), a...Italian ryegrass (Lolium multiflorum) A Johnsongrass (Sorghum halepense) p Kentucky bluegrass (Poa pratensis ) p Lovegrass (Eragrostis spp.) NP Orchard

  8. invazivne biljne vrste u travnjacima saobraćajnica beograda

    African Journals Online (AJOL)

    Bojana Rakocevic

    2011-10-24

    number and cover) and was noticed on all four sites, with marks 2.2, 1.2, 1.1 and +. These are high values considering the fact that four existing good-quality grass species (Poa pratensis,. Lolium perenne, Festuca rubra and Poa ...

  9. A multifunctional phosphine oxide-diphenylamine hybrid compound as a high performance deep-blue fluorescent emitter and green phosphorescent host.

    Science.gov (United States)

    Liu, Xiao-Ke; Zheng, Cai-Jun; Lo, Ming-Fai; Xiao, Jing; Lee, Chun-Sing; Fung, Man-Keung; Zhang, Xiao-Hong

    2014-02-25

    A novel phosphine oxide-diphenylamine hybrid compound POA was designed and synthesized with the aim of developing new multifunctional blue fluorophores. POA is the first kind of compound that can be used as a high-efficiency deep-blue emitter (5.4% EQE) and a host to fabricate high-performance green phosphorescent OLEDs (18.1% EQE).

  10. Revamping the Reproductive Health Agenda in Africa After 2014

    African Journals Online (AJOL)

    AJRH Managing Editor

    continuing marginalization of women, denial of reproductive rights and cultural and religious hindrances still stand in the way of realization of the ICPD POA in Africa. Additionally, there has been lack of political will and determinism by many African governments to implement the POA, with some of the affected countries not.

  11. Onion Park Research Natural Area: Botanical and ecological resources inventory, mapping and analysis with recommendations towards the development of a long-term monitoring and research program

    Science.gov (United States)

    Earle F. Layser

    1992-01-01

    Onion Park is a floristically rich naturally occurring mountain meadow and wetland complex which is surrounded by subalpine forest. The grass- and wetlands comprising the Park contribute biological diversity to an otherwise predominantly lodgepole pine-forested, subalpine setting. Onion Park is located at 7400' elevation in the Little Belt Mountains, five miles...

  12. Determining Clark's nutcracker use of whitebark pine communities in regard to stand health in Waterton-Glacier International Peace Park

    Science.gov (United States)

    Jennifer D. Scott; Diana F. Tomback; Michael B. Wunder

    2011-01-01

    Whitebark pine (Pinus albicaulis), one of five stone pines worldwide, is found at treeline and subalpine elevations in the mountains of western North America (McCaughey and Schmidt 2001). Considered a keystone species, it helps maintain subalpine biodiversity, protects watersheds and promotes post-fire regeneration (Tomback and others 2001). The Clark's nutcracker...

  13. Why a Network Energy Monitoring and Control System?

    Science.gov (United States)

    1985-01-01

    x F Htg : BTT x AZ x (650F-55°F) x (168-H) x 28.6 wks/yr x F/(BEFF x HV) a 286 x BTT x AZ x (168 H) x F/(HEFF x EV) V-clg: CFM x POA x (4.5 lb/cr-hr) x...33.34 - 29.91 Btu/lb) x (168 - H) x 23.4 wks/yr x CPT x F/(12,000 Btu/ton-hr) = .0301 x CFM x POA x (168-H) x CPT x F V- htg : CIX x POA x (1.08 Btu...RECIRCULATION4 *.WU V- htg : CFM4 x POA x (650 - 43.00) x (1.08 Btu/cfm*F-hr) x 232 days/yr x (WH-.25 hr/day)/(HEFF X HV) 5512 x CFM x POA x (WH-.25)/(BEFF x AV

  14. A new approach for pyrazinamide susceptibility testing in Mycobacterium tuberculosis.

    Science.gov (United States)

    Zimic, Mirko; Loli, Sebastian; Gilman, Robert H; Gutierrez, Andrés; Fuentes, Patricia; Cotrina, Milagros; Kirwan, Daniela; Sheen, Patricia

    2012-08-01

    Pyrazinamide (PZA) is an important drug in the treatment of tuberculosis. Microbiological methods of PZA susceptibility testing are controversial and have low reproducibility. After conversion of PZA into pyrazinoic acid (POA) by the bacterial pyrazinamidase enzyme, the drug is expelled from the bacteria by an efflux pump. To evaluate the rate of POA extrusion from Mycobacterium tuberculosis as a parameter to detect PZA resistance. The rate of POA extrusion and PZA susceptibility determined by BACTEC 460 were measured for 34 strains in a previous study. PZA resistance was modeled in a logistic regression with the pyrazinoic efflux rate. POA efflux rate predicted PZA resistance with 70.83%-92.85% sensitivity and 100% specificity compared with BACTEC 460. POA efflux rate could be a useful tool for predicting PZA resistance in M. tuberculosis. Further exploration of this approach may lead to the development of new tools for diagnosing PZA resistance, which may be of public health importance.

  15. Genetic admixture and lineage separation in a southern Andean plant.

    Science.gov (United States)

    Morello, Santiago; Sede, Silvana M

    2016-01-01

    Mountain uplifts have generated new ecologic opportunities for plants, and triggered evolutionary processes, favouring an increase on the speciation rate in all continents. Moreover, mountain ranges may act as corridors or barriers for plant lineages and populations. In South America a high rate of diversification has been linked to Andean orogeny during Pliocene/Miocene. More recently, Pleistocene glacial cycles have also shaped species distribution and demography. The endemic genus Escallonia is known to have diversified in the Andes. Species with similar morphology obscure species delimitation and plants with intermediate characters occur naturally. The aim of this study is to characterize genetic variation and structure of two widespread species of Escallonia: E. alpina and E. rubra We analyzed the genetic variation of populations of the entire distribution range of the species and we also included those with intermediate morphological characters; a total of 94 accessions from 14 populations were used for the Amplified Fragment Length Polymorphism (AFLP) analysis. Plastid DNA sequences (trnS-trnG, 3'trnV-ndhC intergenic spacers and the ndhF gene) from sixteen accessions of Escallonia species were used to construct a Statistical Parsimony network. Additionally, we performed a geometric morphometrics analysis on 88 leaves from 35 individuals of the two E. alpina varieties to further study their differences. Wright's Fst and analysis of molecular variance tests performed on AFLP data showed a significant level of genetic structure at the species and population levels. Intermediate morphology populations showed a mixed genetic contribution from E. alpina var. alpina and E. rubra both in the Principal Coordinates Analysis (PCoA) and STRUCTURE. On the other hand, E. rubra and the two varieties of E. alpina are well differentiated and assigned to different genetic clusters. Moreover, the Statistical Parsimony network showed a high degree of divergence between the

  16. Hepatocellular toxicity of oxalicumone A via oxidative stress injury and mitochondrial dysfunction in healthy human liver cells.

    Science.gov (United States)

    Shi, Si; Yao, Limei; Guo, Kunbin; Wang, Xiangyu; Wang, Qi; Li, Weirong

    2017-11-06

    The marine‑derived oxalicumone A (POA) has been demonstrated as a potent anti‑tumor bioactive agent for a variety of human carcinoma, but to the best of our knowledge, remains to be evaluated in healthy liver cells. As many drugs distribute preferentially in the liver, the present study aimed to investigate the effects of POA on apoptosis, oxidative stress and mitochondrial function in L‑02 healthy liver cells. A Cell‑Counting kit‑8 assay demonstrated that POA inhibits the proliferation of L‑02 cells in a dose‑ and time‑dependent manner. Furthermore, POA induced apoptosis by increasing the percentage of cells in early apoptosis and the sub‑G1 cell cycle, along with causing S‑phase arrest in L‑02 cells. Additionally, POA activated caspase 3, increased the protein expression levels of Fas ligand and B‑cell lymphoma X‑associated protein, and decreased the expression of the anti‑apoptotic protein B‑cell lymphoma 2. POA additionally reduced the content of GSH and the activity of superoxide dismutase, elevated malondialdehyde and nitric oxide levels, increased reactive oxygen species production and the levels of alanine aminotransferase and aspartate aminotransferase, which suggested that POA induced lipid peroxidation injury in L‑02 cells and that oxidative stress serves an important role. Furthermore, POA caused alternations of mitochondrial function, including an abrupt depletion of adenosine triphosphate synthesis, mitochondrial permeability transition pore opening and depletion of mitochondrial membrane potential in L‑02 cells. These data suggested that POA exerts cytotoxicity, at least in part, by inducing oxidative stress, mitochondrial dysfunction, and eventually apoptosis. Changes in mitochondrial function and oxidative stress by POA may therefore be critical in POA‑induced toxicity in L‑02 cells.

  17. In Vivo-Selected Pyrazinoic Acid-Resistant Mycobacterium tuberculosis Strains Harbor Missense Mutations in the Aspartate Decarboxylase PanD and the Unfoldase ClpC1.

    Science.gov (United States)

    Gopal, Pooja; Tasneen, Rokeya; Yee, Michelle; Lanoix, Jean-Philippe; Sarathy, Jansy; Rasic, George; Li, Liping; Dartois, Véronique; Nuermberger, Eric; Dick, Thomas

    2017-07-14

    Through mutant selection on agar containing pyrazinoic acid (POA), the bioactive form of the prodrug pyrazinamide (PZA), we recently showed that missense mutations in the aspartate decarboxylase PanD and the unfoldase ClpC1, and loss-of-function mutation of polyketide synthases Mas and PpsA-E involved in phthiocerol dimycocerosate synthesis, cause resistance to POA and PZA in Mycobacterium tuberculosis. Here we first asked whether these in vitro-selected POA/PZA-resistant mutants are attenuated in vivo, to potentially explain the lack of evidence of these mutations among PZA-resistant clinical isolates. Infection of mice with panD, clpC1, and mas/ppsA-E mutants showed that whereas growth of clpC1 and mas/ppsA-E mutants was attenuated, the panD mutant grew as well as the wild-type. To determine whether these resistance mechanisms can emerge within the host, mice infected with wild-type M. tuberculosis were treated with POA, and POA-resistant colonies were confirmed for PZA and POA resistance. Genome sequencing revealed that 82 and 18% of the strains contained missense mutations in panD and clpC1, respectively. Consistent with their lower fitness and POA resistance level, independent mas/ppsA-E mutants were not found. In conclusion, we show that the POA/PZA resistance mechanisms due to panD and clpC1 missense mutations are recapitulated in vivo. Whereas the representative clpC1 mutant was attenuated for growth in the mouse infection model, providing a possible explanation for their absence among clinical isolates, the growth kinetics of the representative panD mutant was unaffected. Why POA/PZA resistance-conferring panD mutations are observed in POA-treated mice but not yet among clinical strains isolated from PZA-treated patients remains to be determined.

  18. Moxd1 Is a Marker for Sexual Dimorphism in the Medial Preoptic Area, Bed Nucleus of the Stria Terminalis and Medial Amygdala.

    Science.gov (United States)

    Tsuneoka, Yousuke; Tsukahara, Shinji; Yoshida, Sachine; Takase, Kenkichi; Oda, Satoko; Kuroda, Masaru; Funato, Hiromasa

    2017-01-01

    The brain shows various sex differences in its structures. Various mammalian species exhibit sex differences in the sexually dimorphic nucleus of the preoptic area (SDN-POA) and parts of the extended amygdala such as the principal nucleus of the bed nucleus of the stria terminalis (BNSTpr) and posterodorsal part of the medial amygdala (MePD). The SDN-POA and BNSTpr are male-biased sexually dimorphic nuclei, and characterized by the expression of calbindin D-28K (calbindin 1). However, calbindin-immunoreactive cells are not restricted to the SDN-POA, but widely distributed outside of the SDN-POA. To find genes that are more specific to sexually dimorphic nuclei, we selected candidate genes by searching the Allen brain atlas and examined the detailed expressions of the candidate genes using in situ hybridization. We found that the strong expression of monooxygenase DBH-like 1 (Moxd1) was restricted to the SDN-POA, BNSTpr and MePD. The numbers of Moxd1-positive cells in the SDN-POA, BNSTpr and MePD in male mice were larger than those in female mice. Most of the Moxd1-positive cells in the SDN-POA and BNSTpr expressed calbindin. Neonatal castration of male mice reduced the number of Moxd1-positive cells in the SDN-POA, whereas gonadectomy in adulthood did not change the expression of the Moxd1 gene in the SDN-POA in both sexes. These results suggest that the Moxd1 gene is a suitable marker for sexual dimorphic nuclei in the POA, BNST and amygdala, which enables us to manipulate sexually dimorphic neurons to examine their roles in sex-biased physiology and behaviors.

  19. Морфологическое исследование гибридогенного комплекса Poa palustris × nemoralis (Роасеае на Среднем Урале

    Directory of Open Access Journals (Sweden)

    M. V. Olonova

    2015-12-01

    Full Text Available Исследование проявления 25 морфологических признаков в пяти среднеуральских популяциях Pоа palustris L. и P. nemoralis L. выявило высокую степень их изменчивости, как внутрипопуляционной, так и межпопуляционной и большое число особей, сочетающих признаки обоих видов. Это позволяет предполагать гибридную природу всех исследованных популяций и образование надвидовой структуры – сложного гибридогенного комплекса. Статистический анализ подтвердил отличие среднеуральских популяций P. palustris × nemoralis от западносибирских.

  20. Conifer expansion reduces the competitive ability and herbivore defense of aspen by modifying light environment and soil chemistry.

    Science.gov (United States)

    Calder, W John; Horn, Kevin J; St Clair, Samuel B

    2011-06-01

    Disturbance patterns strongly influence plant community structure. What remains less clear, particularly at a mechanistic level, is how changes in disturbance cycles alter successional outcomes in plant communities. There is evidence that fire suppression is resulting in longer fire return intervals in subalpine forests and that these lengthened intervals increase competitive interactions between aspen and conifer species. We conducted a field and greenhouse study to compare photosynthesis, growth and defense responses of quaking aspen and subalpine fir regeneration under light reductions and shifts in soil chemistry that occur as conifers increase in dominance. The studies demonstrated that aspen regeneration was substantially more sensitive to light and soil resource limitations than that of subalpine fir. For aspen, light reductions and/or shifts in soil chemistry limited height growth, biomass gain, photosynthesis and the production of defense compounds (phenolic glycosides and condensed tannins). Biomass gain and phenolic glycoside concentrations were co-limited by light reduction and changes in soil chemistry. In contrast, subalpine fir seedlings tended to be more tolerant of low light conditions and showed no sensitivity to changes in soil chemistry. Unlike aspen, subalpine fir increased its root to shoot ratio on conifer soils, which may partially explain its maintenance of growth and defense. The results suggest that increasing dominance of conifers in subalpine forests alters light conditions and soil chemistry in a way that places greater physiological and growth constraints on aspen than subalpine fir, with a likely outcome being more successful recruitment of conifers and losses in aspen cover.

  1. Milan Army Ammunition Plant. Remedial Investigation Report. Volume 4. Appendices M - T

    Science.gov (United States)

    1991-12-01

    Johnsongrass Sorghum halepense Kentucky bluegrass Poa pratensis Lespedeza bicolor Desnodium bicolor Lespedeza sericea Lespedeza sericea Orchard grass Dactylis... Anthus spinoletta Cedar waxwing Bombycilla cedrorum Loggerhead shrike Lanius ludovicianus Starling Sturnus vulgaris White-eyed vireo Vireo griseus Yellow

  2. Study of SiO2/4H-SiC interface nitridation by post-oxidation annealing in pure nitrogen gas

    Directory of Open Access Journals (Sweden)

    Atthawut Chanthaphan

    2015-09-01

    Full Text Available An alternative and effective method to perform interface nitridation for 4H-SiC metal-oxide-semiconductor (MOS devices was developed. We found that the high-temperature post-oxidation annealing (POA in N2 ambient was beneficial to incorporate a sufficient amount of nitrogen atoms directly into thermal SiO2/SiC interfaces. Although N2-POA was ineffective for samples with thick thermal oxide layers, interface nitridation using N2-POA was achieved under certain conditions, i.e., thin SiO2 layers (1350°C. Electrical characterizations of SiC-MOS capacitors treated with high-temperature N2-POA revealed the same evidence of slow trap passivation and fast trap generation that occurred in NO-treated devices fabricated with the optimized nitridation conditions.

  3. Environmental Assessment of Installation Development at McConnell Air Force Base, Kansas

    Science.gov (United States)

    2012-12-01

    such as tall fescue (Festuca arundinacea), Bermuda grass (Cynodon dactylon), smooth brome (Bromus inermis), Johnson grass (Sorghum halapense), sweet...dominant species include tall fescue (Festua arundinacea), smooth brome (Bromus inermis), and Kentucky bluegrass (Poa pratensis). Tall fescue and

  4. 78 FR 37327 - Endangered and Threatened Wildlife and Plants; Proposed Designation of Critical Habitat for the...

    Science.gov (United States)

    2013-06-20

    ... species of grasses such as bluegrass (Poa spp.), slender wheatgrass (Elymus trachycaulus), brome (Bromus spp.), foxtail barley (Hordeum jubatum), or Japanese brome (Bromus japonicas), and forbs such as water...

  5. Final Environmental Assessment Addressing New Construction and Demolition at Beale Air Force Base, California

    Science.gov (United States)

    2014-04-01

    at Beale AFB include mostly naturalized annual grass species including ripgut brome (Bromus diandrus), Italian rye grass (Lolium multiflorum), soft...Vicia sp.), Ripgut brome (Bromus diandrus.), white brodiaea (Triteleia 30  hyacinthina), English plantain (Plantago lanceolata), annual bluegrass (Poa

  6. Effectiveness and costeffectiveness of screening immigrants schemes for tuberculosis (TB) on arrival from high TB endemic countries to low TB prevalent countries

    National Research Council Canada - National Science Library

    Sanneh, A F N S; Al-Shareef, A M

    2014-01-01

    ...) Screening immigrants at ports of entry referred to as "Port of Arrival Screening" (PoA) and 2) Passive screening (PS) for TB which means screening immigrants through general practices, hospitals, chest-clinics and emergency departments...

  7. Effectiveness and cost effectiveness of screening immigrants schemes for tuberculosis (TB) on arrival from high TB endemic countries to low TB prevalent countries

    National Research Council Canada - National Science Library

    Sanneh, A F N S; Al-Shareef, A M

    2014-01-01

    ...) Screening immigrants at ports of entry referred to as "Port of Arrival Screening" (PoA) and 2) Passive screening (PS) for TB which means screening immigrants through general practices, hospitals, chest-clinics and emergency departments...

  8. The medial preoptic area is necessary for motivated choice of pup- over cocaine-associated environments by early postpartum rats.

    Science.gov (United States)

    Pereira, M; Morrell, J I

    2010-05-05

    Converging evidence suggests that the motivation to seek cocaine during the postpartum period is significantly impacted by the competing incentives of offspring, a stimulus unique to this life stage. In the present study, the functional role of the medial preoptic area (mPOA), a critical site involved in maternal responsiveness, on processing incentive value of pup-associated cues and influencing response allocation for pup- over cocaine-associated environments was investigated using a concurrent pup/cocaine choice conditioned place preference (CPP) paradigm. Early postpartum females with bilateral guide cannulae aimed into the mPOA or into anatomical control sites were conditioned, from postpartum days (PPD) 4 to 7, to associate different uniquely featured environments with pups or cocaine. CPP was tested on PPD8 following intra-mPOA infusions of either 2% bupivacaine or saline vehicle. In two additional experiments, the effects of intra-mPOA infusions of bupivacaine on expression of conditioned responding induced by environments associated with either pups or cocaine were examined separately. Transient inactivation of the mPOA selectively blocked the conditioned preferences for pup-associated environments, significantly contrasting the robust pup-CPP found in non-surgical and intra-mPOA vehicle-treated females. In contrast, mPOA inactivation failed to alter cocaine-CPP in postpartum females. When given a choice between environments associated with pups or cocaine, transient functional inactivation of the mPOA altered choice behavior, biasing the preference of females toward cocaine-associated environments, such that almost all preferred cocaine- and none the pup-associated option. The anatomical specificity was revealed when inactivation of adjacent regions to the mPOA did not affect CPP responses for pups. The findings support a critical role for the mPOA in mediating pup-seeking behavior, and further suggest that the competing properties of pups over

  9. KC-46A Third Main Operating Base (MOB 3) Beddown Environmental Impact Statement (EIS)

    Science.gov (United States)

    2017-04-01

    Sprague’s Pipit Anthus $-pragueii season. W1ntC11ng bttQ$1Jt::cmJ’t..s goyltw oub!jdorofj!etspeciespmft!e ilctjoo?spgxte~BOGQ Swainson’s Hawk...Agrostis tenuis brome Bromus macrostachys tall fescue Festuca arundinacea meadow fescue Festuca elatior Kentucky bluegrass Poa pratensis Shrubs...creeping red fescue Festuca rubra perennial ryegrass Lolium perenne timothy Phleum pratense Kentucky bluegrass Poa pratensis Shrubs eastern red

  10. Does growth rate determine the rate of metabolism in shorebird chicks living in the arctic?

    NARCIS (Netherlands)

    Williams, Joseph B.; Tieleman, B. Irene; Visser, G. Henk; Ricklefs, Robert E.

    2007-01-01

    We measured resting and peak metabolic rates (RMR and PMR, respectively) during development of chicks of seven species of shorebirds: least sandpiper (Calidris minutilla; adult mass 20 22 g), dunlin (Calidris alpina; 56-62 g), lesser yellowlegs (Tringa flavipes; 88-92 g), short-billed dowitcher

  11. Influence of Bud Position on Mother Stem And Soaking Duration on ...

    African Journals Online (AJOL)

    cntaganda

    alpina, predominantly found in the north around Volcano National Park and. Bambusa vulgaris in the forests of Crest-Zaire-Nile region of the country. For the country to exploit the potential of bamboo it is imperative to establish a propagation protocol to effectively multiply and supply the required amount of planting materials ...

  12. AcEST: DK948548 [AcEST

    Lifescience Database Archive (English)

    Full Text Available sicum... 431 e-120 sp|O24339|CATA_SOLAP Catalase OS=Soldanella alpina PE=2 SV=1 430 e-120 sp|P32290|CATA_PHA...VK Sbjct: 181 ESLHMFTFLFDDIGIPQDYRHMDGSGVHTFTLINRAGKSTYVK 223 >sp|O24339|CATA_SOLAP Catalase OS=Soldanella a

  13. AcEST: DK949890 [AcEST

    Lifescience Database Archive (English)

    Full Text Available _GOSHI Catalase isozyme 1 OS=Gossypium hirsutum G... 401 e-111 sp|O24339|CATA_SOLAP Catalase OS=Soldanella a...8 EGFMNFMHRDEEINYFPSRYDPVRHAEMFPIPPAVCT 414 >sp|O24339|CATA_SOLAP Catalase OS=Soldanella alpina PE=2 SV=1 Le

  14. AcEST: DK951242 [AcEST

    Lifescience Database Archive (English)

    Full Text Available umbagini... 398 e-110 sp|O24339|CATA_SOLAP Catalase OS=Soldanella alpina PE=2 SV=1 397 e-110 sp|P25819|CATA2...FSHHP 180 Query: 628 ESMHMFSWLFDDVGIPLNYRH 690 ES+HMFS+LFDD+G+P +YRH Sbjct: 181 ESLHMFSFLFDDLGVPQDYRH 201 >sp|O24339|CATA_SOLAP

  15. AcEST: DK943980 [AcEST

    Lifescience Database Archive (English)

    Full Text Available S=Arabidopsis thaliana GN=CAT1... 32 1.00 sp|O24339|CATA_SOLAP Catalase OS=Soldanella alpina PE=2 SV=1 31 1.... 1 AQADKSLGQKVGMRLNVKSN 60 +QADKSLGQK+ RLNV+ N Sbjct: 472 SQADKSLGQKLATRLNVRPN 491 >sp|O24339|CATA_SOLAP

  16. AcEST: DK957364 [AcEST

    Lifescience Database Archive (English)

    Full Text Available N=CAT2... 249 5e-66 sp|P49317|CATA3_NICPL Catalase isozyme 3 OS=Nicotiana plumbagini... 248 1e-65 sp|O24339|CATA_SOLAP...KFYT 128 >sp|O24339|CATA_SOLAP Catalase OS=Soldanella alpina PE=2 SV=1 Length = 492 Score = 247 bits (631),

  17. AcEST: DK955512 [AcEST

    Lifescience Database Archive (English)

    Full Text Available AT4 PE=2 SV=1 332 6e-91 sp|P49317|CATA3_NICPL Catalase isozyme 3 OS=Nicotiana plumbagini... 332 6e-91 sp|O24339|CATA_SOLAP...121 GFAVKFYTREGNFDLVGNNFPVFFVRDGMKFPDMVHALKPNPKSHIQ 167 >sp|O24339|CATA_SOLAP Catalase OS=Soldanella alpina

  18. AcEST: DK950143 [AcEST

    Lifescience Database Archive (English)

    Full Text Available ... 398 e-110 sp|O24339|CATA_SOLAP Catalase OS=Soldanella alpina PE=2 SV=1 397 e-110 sp|P25819|CATA2_ARATH C...0 Query: 619 ESMHMFSWLFDDVGIPLNYRH 681 ES+HMFS+LFDD+G+P +YRH Sbjct: 181 ESLHMFSFLFDDLGVPQDYRH 201 >sp|O24339|CATA_SOLAP

  19. AcEST: DK950258 [AcEST

    Lifescience Database Archive (English)

    Full Text Available umbagini... 395 e-109 sp|O24339|CATA_SOLAP Catalase OS=Soldanella alpina PE=2 SV=1 394 e-109 sp|P25819|CATA2... Query: 632 ESMHMFSWLFDDVGIPLNYR 691 ES+HMFS+LFDD+G+P +YR Sbjct: 181 ESLHMFSFLFDDLGVPQDYR 200 >sp|O24339|CATA_SOLAP

  20. AcEST: DK949197 [AcEST

    Lifescience Database Archive (English)

    Full Text Available GOSHI Catalase isozyme 2 OS=Gossypium hirsutum G... 432 e-121 sp|O24339|CATA_SOLAP Catalase OS=Soldanella al...t: 181 ESLHMFTFLFDDIGVPQDYRHMDGSGVHTYTLINKAGKSHYVKFH 225 >sp|O24339|CATA_SOLAP Catalase OS=Soldanella alpina

  1. AcEST: DK948290 [AcEST

    Lifescience Database Archive (English)

    Full Text Available .. 415 e-116 sp|O24339|CATA_SOLAP Catalase OS=Soldanella alpina PE=2 SV=1 411 e-114 sp|P32290|CATA_PHAAU Cat...MFSWLFDDVGIPLNYRHMEGFGVHTFT 653 ES+HMF++LFDD+G+P +YRHM+G GVHT+T Sbjct: 181 ESLHMFTFLFDDIGVPQDYRHMDGSGVHTYT 211 >sp|O24339|CATA_SOLAP

  2. Some new or noteworthy species of Mortierella

    NARCIS (Netherlands)

    Gams, W.

    1976-01-01

    Twenty-two species of Mortierella are described and distributed over the sections defined by Gams (1970) which include the following new species: Section Pusilla: M. roseo-nana; Section Alpina: M. globalpina and M. polygonia Section Simplex: M. amoeboidea; Section Hygrophila : M. elongatula, M.

  3. Habitat use and diet selection of northward migrating waders in the Sivash (Ukraine) : The use of Brine Shrimp Artemia salina in a variably saline lagoon complex

    NARCIS (Netherlands)

    Verkuil, Y.I.; Van der Have, TM; Van der Winden, J; Chernichko, [No Value

    2003-01-01

    Wader species migrating through the Sivash (Ukraine) use hypersaline and brackish lagoons. We studied the use of the two habitat types, and focused on the profitability of Brine Shrimp Artemia salina, prey species in hypersaline lagoons for Dunlins Calidris alpina, Curlew Sandpipers Calidris

  4. Habitat use and diet selection of northward migrating waders in the Sivash (Ukraine): the use of brine shrimp Artemia salina in a variably saline lagoon complex.

    NARCIS (Netherlands)

    Verkuil, Y.; Have, van der T.M.; Winden, van der J.; Chernichko, I.I.

    2003-01-01

    Wader species migrating through the Sivash (Ukraine) use hypersaline and brackish lagoons. We studied the use of the two habitat types, and focused on the profitability of Brine Shrimp Artemia salina, prey species in hypersaline lagoons for Dunlins Calidris alpina, Curlew Sandpipers Calidris

  5. The effects of selected anatomical characteristics on physical ...

    African Journals Online (AJOL)

    The effects of selected anatomical characteristics on physical properties of Ethiopian Highland Bamboo Arundinaria Alpina K. Schum. (Poaceae) ... In early maturing bamboo, fibers are relatively small in wall thickness. The results of statistical analyses revealed that bamboo portion has significant effects on all variables.

  6. The effect of silvicultural management on regeneration, growth and ...

    African Journals Online (AJOL)

    With the objective of determining the effects of silvicultural management on regeneration and growth of mismanaged Arundinaria alpina stands, an experiment was conducted in the Choke Mountain, northwest Ethiopia. Eight soil and plant management techniques that comprise soil loosening, selective thinning and removal ...

  7. Phytochemical, Antioxidant and Antimicrobial Profiles of Extracts of ...

    African Journals Online (AJOL)

    Pharmacotherapy Group, Faculty of Pharmacy, University of Benin, Benin City, 300001 Nigeria. All rights ... HPLC analysis of the extracts showed the ... we relate here the results of the phytochemical analysis (total phenols, flavonoid content, HPLC-. UV) of leaf and twigs of Daphne alpina. EXPERIMENTAL. Plant materials.

  8. Mitochondrial DNA sequence evolution in shorebird populations

    NARCIS (Netherlands)

    Wenink, P.W.

    1994-01-01

    This thesis describes the global molecular population structure of two shorebird species, in particular of the dunlin, Calidris alpina, by means of comparative sequence analysis of the most variable part of the mitochondrial DNA (mtDNA) genome. There are several reasons

  9. New uses of bioglycerin: production of arachidonic acid

    Science.gov (United States)

    Filamentous fungi of the genus Mortierella are known to produce arachidonic acid from glucose and M. alpina is currently used in industrial scale production of arachidonic acid in Japan. In anticipation of a large excess of co-product bioglycerin from the national biodiesel program, we would like ...

  10. Nuevos registros de aves para la Isla María Madre, Nayarit, México

    OpenAIRE

    Contreras Balderas, Armando J.

    2016-01-01

    The present paper includes nine species of birds here reported from collections made in October 1979 and August 1980. These are: Calidris alpina pacifica, Limnodromus griseus hendersoni, Gallinogo gallinago delicata, Crotophaga sulcirostris sulcirostris, Chloroceryle americano hachisukai, Spiza americana, and Melozpisa lincolnii lincolnii. Fragata magnificens and the exotic Passer domesticus were observed but not collected.

  11. Circaea x intermedia Ehrh. (Klein heksenkruid) een tuinplant?

    NARCIS (Netherlands)

    Beringen, Ruud

    2001-01-01

    Circaea x intermedia, a very rare taxon in the Netherlands, was found on a new locality on the edge of a woodland near the outskirts of the town of Ede. Growing conditions on the site are not suitable for both parental species ( C. alpina and C. lutetiana). Therefore it is most unlikely the hybrid

  12. Polyphenolic Composition, Antioxidant and Antibacterial Activities for Two Romanian Subspecies of Achillea distans Waldst. et Kit. ex Willd.

    Directory of Open Access Journals (Sweden)

    Radu Silaghi-Dumitrescu

    2013-07-01

    Full Text Available The aim of this work was to study the chemical composition, antioxidant and antibacterial properties of Achillea distans Waldst. et Kit. subsp. distans and Achillea distans Waldst. et Kit. subsp. alpina Rochel, from the Rodna Mountains (Romania. The identification and quantification of major phenolic compounds was performed by a HPLC-MS method. The total polyphenolic and flavonoid content was determined spectrophotometrically. The antioxidant activity was evaluated using the DPPH bleaching method, trolox equivalent antioxidant capacity assay (TEAC, hemoglobin ascorbate peroxidase activity inhibition (HAPX assay, and an Electron Paramagnetic Resonance (EPR spectroscopy method. A data indicated that A. distans subsp. alpina extract has more antioxidant activity than A. distans subsp. distans extract. Luteolin, apigenin, quercetin, caffeic and chlorogenic acids were present in the two extracts of A. distans, but in different amounts. Three flavonoids were detected only in A. distans subsp. alpina. The polyphenol-richer A. distans subsp. alpina extract showed a higher antioxidant activity than A. distans subsp. distans extract. A. distans subsp. distans extract showed inhibitory activity for Gram-positive bacteria, as evaluated with four species. The quantitative and qualitative differences between the two subspecies of Achillea distans could be used as a potential taxonomic marker in order to distinguish the species.

  13. Metabolic engineering of Saccharomyces cerevisiae for production of eicosapentaenoic acid, using a novel δ5-desaturase from Paramecium tetraurelia

    DEFF Research Database (Denmark)

    de Andrade Pereira Tavares, Sabina; Grotkjær, Thomas; Obsen, Thomas

    2011-01-01

    . lucimarinus, O. tauri, and M. alpina are promiscuous toward the acyl carrier substrate but prefer phospholipid-bound substrates. In contrast, the Δ5-desaturase from L. major showed no activity on phospholipid-bound substrate and thus appears to be an exclusively acyl coenzyme A-dependent desaturase. ©American...

  14. Inhibition of cisplatin-resistance by RNA interference targeting metallothionein using reducible oligo-peptoplex.

    Science.gov (United States)

    Lee, Jong-Hwan; Chae, Ji-Won; Kim, Jang Kyoung; Kim, Hyung Jin; Chung, Jee Young; Kim, Yong-Hee

    2015-10-10

    Effective intracellular level of a platinum anti-cancer drug, cisplatin, following repeated injections can be decreased either by the active efflux via ATP pump or by interactions with glutathione and metallothionein. Cisplatin in cytoplasm preferably binds to cysteine-rich proteins such as glutathione and metallothionein (MT). Detoxification of cisplatin by intracellular thiol-containing proteins has been considered to be major hurdles to overcome. The short hairpin RNA targeting MT (shMT) was tested to down-regulate MT and recover cisplatin resistance. A reducible polymer, poly(oligo-d-arginine) (rPOA), formed stable complex with shMT and demonstrated superior transfection efficiency. Efficient transfection of shMT/rPOA oligo-peptoplexes was found to significantly inhibit MT over-expression, resulting in 45% decrease of cell viability compared to the cisplatin alone group. This decrease was mediated by the synergistic effect of shMT/rPOA oligo-peptoplex and cisplatin. Co-administration of shMT/rPOA oligo-peptoplex and cisplatin in in vivo tumor model showed noticeable tumor-suppressing effect by inducing reversal of cisplatin resistance following effective intracellular delivery of shMT by rPOA. Combination therapy through co-administration of shMT/rPOA oligo-peptoplex and cisplatin was found to effectively reverse cisplatin resistance by RNA interference and consequently improve anti-cancer activity of cisplatin. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Differences in ovarian function parameters between Chinese and Caucasian oocyte donors: do they offer an explanation for lower IVF pregnancy rates in Chinese women?

    Science.gov (United States)

    Gleicher, Norbert; Weghofer, Andrea; Li, JiangMi; Barad, David

    2007-11-01

    IVF outcomes in Chinese women are inferior to those of Caucasian patients. Reflecting prematurely diminished ovarian function, women with elevated age-specific baseline (b-) FSH levels are designated to suffer from premature ovarian aging (POA). We investigated if the prevalence of POA differs between these two ethnic populations. We compared patient characteristics and first IVF cycle outcomes in 29 consecutive, Caucasian and 17 Asian-Chinese oocyte donors. POA was diagnosed in a donor if her b-FSH levels exceeded the 95% confidence interval (CI) for her age group. There was no age difference between Chinese and Caucasian groups (26.2 +/- 4.9 versus 25.7 +/- 3.1 years, respectively). Chinese women demonstrated, however, a higher cycle cancellation rate (5/17, 29.4%), either before cycle start or during stimulation (0/29; relative risk 1.42, 95% CI 1.04-1.9; P Chinese and only 1/26 (4%) of Caucasian donors met b-FSH level criteria for a presumptive POA diagnosis. Their odds of meeting POA criteria were approximately 30-times greater (odds ratio 31.5; 95% CI 3.5-18.7; P Chinese women. Preceding treatment, Chinese women at all ages should be carefully investigated to detect occult POA. Ethnicity may have to be considered an additional outcome variable in fertility studies.

  16. Effect of chronic cold exposure on noradrenergic modulation in the preoptic area of thermoregulation in freely moving rats.

    Science.gov (United States)

    Saito, Takehito; Ishiwata, Takayuki; Hasegawa, Hiroshi; Nomoto, Shigeki; Kotani, Yasunori; Otokawa, Minoru; Aihara, Yasutsugu

    2008-07-04

    For this study, we compared the thermoregulatory involvement of noradrenaline (NA) in the medial preoptic area (mPOA) of non-cold acclimated rats to that of cold-acclimated rats. We quantified the release of NA in the mPOA during 3 h cold (5 degrees C) exposure in room-temperature-acclimated rats (RA group, kept at 23 degrees C for 2 weeks) and cold-acclimated rats (CA group, kept at 5 degrees C for 2 weeks). We concurrently monitored the core body temperature (Tc), heart rate (HR), and tail skin temperature (Tt). Cold exposure significantly increased Tc and HR, and decreased Tt in both groups. However, the cold-induced increase of the extracellular NA levels in mPOA was observed only in the RA group: not in the CA group. To elucidate these different results in NA levels further, and to evaluate participation of the mPOA in thermoregulation in the cold, we measured Tc, HR, and Tt during perfusion of alpha-adrenoceptor antagonist phenoxybenzamine during cold exposure (5 degrees C). This pharmacological procedure induced marked hypothermia, with decreases in HR only in the RA group; no changes were observed in Tc or any thermoregulatory parameter in the CA group. These results suggest that NA in the mPOA modulates heat production in response to acute cold stress in the RA group. However, this thermoregulatory action of NA in the mPOA was attenuated in the CA group.

  17. Where are you sucking from? Using Stable Isotopes to understand Host Specificity in two Hemiparasitic plants above the tree line in Northern Sweden

    Science.gov (United States)

    Macias Sevde, A. S.

    2012-12-01

    By Alejandro Macias, Erik Hobbie, Ruth Varner, Kaitlyn Steele Hemiparasites are known to suck nutrients from nearby plants but their host specificity is not well understood. Hemiparasites are ecosystem engineers, limiting surrounding plant's growth, and decreasing local biodiversity. To better understand this phenomenon, the host specificities of two hemiparasitic angiosperms, Bartsia alpina , and Pedicularis lapponica were studied above the tree line along an elevational gradient in Sweden. B. alpina specialized in wetter environments, as indicated by their higher δ13C signature, and their growth among Salixsp.Betula nana, Bistorta vivipara, Viola biflora, Geranium sp., and Trollious europaeus. P. lapponica was common in drier, less species rich environments, known as heaths, where B. nana, Empetrum negrum, Phyllodoce coeruela, Vaccinium myrtillus and Vaccinium vitis-idaea are the most common species. P. lapponica had higher foliage δ13C due to its better water-use efficiency in a dry environment. Field survey data and δN15 values of both the foliage of the parasitic plants and their potential hosts were used to determine host specificity. Since the δN15 value of the hemiparasitic plant and its host are similar due to parasitism, it was determined that P. lapponica had a preference for plants with an ericoid mycorrhizal association, such as Vaccinium sp, and E. negrum, but not for the common P. coeruela. This does not support the idea found in the literature that P. lapponica has a preference for grasses. B. alpina was less host specific, associating with non-mycorrhizal, ericoid, and ectomycorhizal plants, such as Carex sp, Vaccinium sp., and S. lapponum. The ectomycorrhizal species, Salix sp., and B. nana, were both potential hosts for B. alpina and P. lapponica due to their presence among them. However, the isotopic data revealed that B. alpina had a preference for Salix sp., and P. lapponica had a preference for B. nana.

  18. High performance graphene-poly (o-anisidine) nanocomposite for supercapacitor applications

    Energy Technology Data Exchange (ETDEWEB)

    Basnayaka, Punya A. [Department of Mechanical Engineering, University of South Florida, 4202 E Fowler Avenue, ENB 118, Tampa, FL 33620 (United States); Clean Energy Research Center, University of South Florida, 4202 E Fowler Avenue, ENB 118, Tampa, FL 33620 (United States); Ram, Manoj K., E-mail: mkram@usf.edu [Clean Energy Research Center, University of South Florida, 4202 E Fowler Avenue, ENB 118, Tampa, FL 33620 (United States); Nanotechnology Research and Education Center, University of South Florida, 4202 E Fowler Avenue, ENB 118, Tampa, FL 33620 (United States); Stefanakos, Lee [Clean Energy Research Center, University of South Florida, 4202 E Fowler Avenue, ENB 118, Tampa, FL 33620 (United States); Kumar, Ashok [Department of Mechanical Engineering, University of South Florida, 4202 E Fowler Avenue, ENB 118, Tampa, FL 33620 (United States); Clean Energy Research Center, University of South Florida, 4202 E Fowler Avenue, ENB 118, Tampa, FL 33620 (United States)

    2013-08-15

    Our previous exciting results on graphene (G)-conducting polymer (polyaniline (PANI) and polyethylenedioxythiophene (PEDOT)) supercapacitors have prompted the investigation of G-substituted conducting polymer nanocomposites used as electrode materials in supercapacitors. The solubility of ortho-substituted PANI derivatives in a few common solvents has allowed the fabrication of stretchable films by the casting technique. The G-poly (o-anisidine) (G-POA) nanocomposites were synthesized with different weight ratios of G to o-anisidine by chemical methods, and characterized by various techniques, such as, scanning electron microscopy, transmission electron microscopy, UV–visible spectroscopy, Raman spectroscopy, thermogravimetric analysis and cyclic voltammetry. The electrical conductivity and specific capacitance obtained for the G-POA nanocomposites were found to be dependent on the weight ratios of G to o-anisidine. The specific capacitance and the charging–discharging behavior of the POA and G-POA supercapacitors were investigated in a 2 M H{sub 2}SO{sub 4}, 0.2 M LiClO{sub 4} and 1 M 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM-PF{sub 6}) ionic liquid. The specific capacitance of 380 F g{sup −1} was calculated for the 1:1 weight ratio of G to o-anisidine based G-POA supercapacitor in 2 M H{sub 2}SO{sub 4}. The presence of the electron-donating group (–OCH{sub 3}) in the o-anisidine allows the electrons through the lone pair of nitrogen atoms to enhance the electronic charge transport inside the G-POA supercapacitor electrodes. However, the G-POA-based supercapacitors showed a 27% decrease in the specific capacitance in H{sub 2}SO{sub 4} and 16% decrease in the ionic liquid (BMIM-PF{sub 6}) after 1000 cycles of charging and discharging. The higher stability and rate capability of the G-POA based supercapacitor in an ionic liquid (BMIM-PF{sub 6}) as compared to an aqueous electrolytic supercapacitor opens the door for the fabrication of stable

  19. Advance directives and power of attorney for health care in the oldest-old - results of the AgeQualiDe study.

    Science.gov (United States)

    Luck, Tobias; Rodriguez, Francisca S; Wiese, Birgitt; van der Leeden, Carolin; Heser, Kathrin; Bickel, Horst; In der Schmitten, Jürgen; Koenig, Hans-Helmut; Weyerer, Siegfried; Mamone, Silke; Mallon, Tina; Wagner, Michael; Weeg, Dagmar; Fuchs, Angela; Brettschneider, Christian; Werle, Jochen; Scherer, Martin; Maier, Wolfgang; Riedel-Heller, Steffi G

    2017-04-13

    Completion of advance directives (ADs) and power of attorney (POA) documents may protect a person's autonomy in future health care situations when the individual lacks decisional capacity. As such situations become naturally much more common in old age, we specifically aimed at providing information on (i) the frequency of ADs/POA in oldest-old individuals and (ii) factors associated with having completed ADs/POA. We analyzed data of oldest-old primary care patients (85+ years; including community-dwelling and institutionalized individuals) within the German AgeQualiDe study. Patients were initially recruited via their general practitioners (GPs). We calculated frequencies of ADs and POA for health care with 95% confidence intervals (CI) and used multivariable logistic regression analysis to evaluate the association between having ADs and POA and participants' socio-demographic, cognitive, functional, and health-related characteristics. Among 868 GP patients participating in AgeQualiDe (response = 90.9%), n = 161 had dementia and n = 3 were too exhausted/ill to answer the questions. Out of the remaining 704 (81.1%) dementia-free patients (mean age = 88.7 years; SD = 3.0), 69.0% (95%-CI = 65.6-72.4) stated to having ADs and 64.6% (95%-CI = 61.1-68.2) to having a POA for health care. Individual characteristics did not explain much of the variability of the presence/absence of ADs and POA (regression models: Nagelkerke's R2 = 0.034/0.051). The most frequently stated reasons for not having ADs were that the older adults trust their relatives or physicians to make the right decisions for them when necessary (stated by 59.4% and 44.8% of those without ADs). Among the older adults with ADs, the majority had received assistance in its preparation (79.0%), most frequently from their children/grandchildren (38.3%). Children/grandchildren were also the most frequently stated group of designated persons (76.7%) for those with a POA for health care. Our

  20. Effectiveness and cost effectiveness of screening immigrants schemes for tuberculosis (TB) on arrival from high TB endemic countries to low TB prevalent countries.

    Science.gov (United States)

    Sanneh, A F N S; Al-Shareef, A M

    2014-09-01

    Immigrants to developed countries are a major source of TB. Therefore amongst strategies adopted for TB control in developed countries include; 1) Screening immigrants at ports of entry referred to as "Port of Arrival Screening" (PoA) and 2) Passive screening (PS) for TB which means screening immigrants through general practices, hospitals, chest-clinics and emergency departments. Evidence of the effectiveness and cost effectiveness of these strategies is not consistent. Evaluate efficiency of active PoA TB screening for immigrants from TB endemic-regions compared with Passive Screening of immigrant-populations from TB endemic-regions. Major electronic-databases and reference lists of relevant studies were searched. Experts of immigrants' TB screening were contacted for additional studies published or unpublished. Systematic search of major databases identified only retrospective cohort-studies. Their qualities were assessed using Scottish Intercollegiate Guidelines Network (SIGN) methodological checklist for comparative cohort-studies. Systematic electronic searches identified 1443 citations. Of these 74 studies were retrieved for evaluation against the review's inclusion/exclusion criteria (see study inclusion/exclusion criteria). Four studies met the inclusion criteria (figure 2) which were low in the evidence hierarchy of primary effectiveness studies and had heterogeneities between them. Thus descriptive data-synthesis was performed. Proportionately PoA screening had the lowest percentage of receipt of tuberculin skin test (TST) and the highest percentage of non-attendance for TST reading (table 2). Active PoA screening reduced infectiousness by 34% compared to 30% by passive screening and new entrants screened at PoA were 80% less likely to be hospitalised Odds ratio (OR) = 0.2 (95% confidence interval (CI) 0.1 - 0.2). [Table: see text]. One cost effectiveness analysis was found that compared the costs of; active PoA screening, general practice screening and

  1. Evaluation of chemical transport model predictions of primary organic aerosol for air masses classified by particle component-based factor analysis

    Directory of Open Access Journals (Sweden)

    C. A. Stroud

    2012-09-01

    Full Text Available Observations from the 2007 Border Air Quality and Meteorology Study (BAQS-Met 2007 in Southern Ontario, Canada, were used to evaluate predictions of primary organic aerosol (POA and two other carbonaceous species, black carbon (BC and carbon monoxide (CO, made for this summertime period by Environment Canada's AURAMS regional chemical transport model. Particle component-based factor analysis was applied to aerosol mass spectrometer measurements made at one urban site (Windsor, ON and two rural sites (Harrow and Bear Creek, ON to derive hydrocarbon-like organic aerosol (HOA factors. A novel diagnostic model evaluation was performed by investigating model POA bias as a function of HOA mass concentration and indicator ratios (e.g. BC/HOA. Eight case studies were selected based on factor analysis and back trajectories to help classify model bias for certain POA source types. By considering model POA bias in relation to co-located BC and CO biases, a plausible story is developed that explains the model biases for all three species.

    At the rural sites, daytime mean PM1 POA mass concentrations were under-predicted compared to observed HOA concentrations. POA under-predictions were accentuated when the transport arriving at the rural sites was from the Detroit/Windsor urban complex and for short-term periods of biomass burning influence. Interestingly, the daytime CO concentrations were only slightly under-predicted at both rural sites, whereas CO was over-predicted at the urban Windsor site with a normalized mean bias of 134%, while good agreement was observed at Windsor for the comparison of daytime PM1 POA and HOA mean values, 1.1 μg m−3 and 1.2 μg m−3, respectively. Biases in model POA predictions also trended from positive to negative with increasing HOA values. Periods of POA over-prediction were most evident at the urban site on calm nights due to an overly-stable model surface layer

  2. Evaluation of chemical transport model predictions of primary organic aerosol for air masses classified by particle component-based factor analysis

    Science.gov (United States)

    Stroud, C. A.; Moran, M. D.; Makar, P. A.; Gong, S.; Gong, W.; Zhang, J.; Slowik, J. G.; Abbatt, J. P. D.; Lu, G.; Brook, J. R.; Mihele, C.; Li, Q.; Sills, D.; Strawbridge, K. B.; McGuire, M. L.; Evans, G. J.

    2012-09-01

    Observations from the 2007 Border Air Quality and Meteorology Study (BAQS-Met 2007) in Southern Ontario, Canada, were used to evaluate predictions of primary organic aerosol (POA) and two other carbonaceous species, black carbon (BC) and carbon monoxide (CO), made for this summertime period by Environment Canada's AURAMS regional chemical transport model. Particle component-based factor analysis was applied to aerosol mass spectrometer measurements made at one urban site (Windsor, ON) and two rural sites (Harrow and Bear Creek, ON) to derive hydrocarbon-like organic aerosol (HOA) factors. A novel diagnostic model evaluation was performed by investigating model POA bias as a function of HOA mass concentration and indicator ratios (e.g. BC/HOA). Eight case studies were selected based on factor analysis and back trajectories to help classify model bias for certain POA source types. By considering model POA bias in relation to co-located BC and CO biases, a plausible story is developed that explains the model biases for all three species. At the rural sites, daytime mean PM1 POA mass concentrations were under-predicted compared to observed HOA concentrations. POA under-predictions were accentuated when the transport arriving at the rural sites was from the Detroit/Windsor urban complex and for short-term periods of biomass burning influence. Interestingly, the daytime CO concentrations were only slightly under-predicted at both rural sites, whereas CO was over-predicted at the urban Windsor site with a normalized mean bias of 134%, while good agreement was observed at Windsor for the comparison of daytime PM1 POA and HOA mean values, 1.1 μg m-3 and 1.2 μg m-3, respectively. Biases in model POA predictions also trended from positive to negative with increasing HOA values. Periods of POA over-prediction were most evident at the urban site on calm nights due to an overly-stable model surface layer. This model behaviour can be explained by a combination of model under

  3. Post-conflict opponent affiliation reduces victim re-aggression in a family group of captive arctic wolves (Canis lupus arctos).

    Science.gov (United States)

    Lazzaroni, Martina; Marshall-Pescini, Sarah; Cafazzo, Simona

    2017-01-01

    Post-conflict affiliative interactions have been widely investigated in primates but not extensively in other species. Using the Post Conflict-Matched Control (PC-MC) comparison method, this study investigated the patterns of post-conflict opponent affiliation (POA) of a captive family group of 19 arctic wolves (Canis lupus arctos), investigating the correlation with various factors. We found that POAs occurred mainly in the non-feeding context and more often when the victim was dominant and the aggressor subordinate. Furthermore, POAs were more likely to have been initiated by the victim than the aggressor. Victims' stress related behaviours occurred more in PC than MC periods, and more after high vs. low intensity aggressions but they were not more likely to occur after conflicts between wolves with a stronger social bond and POAs did not reduce their rate of occurrence. Our results showed that re-aggression was twice less frequent when a friendly interaction occurred between the aggressor and the victim, and consistent with this, victims engaged in POAs more often than the aggressor. Overall, our results support the hypothesis that POAs in wolves may have been selected for as a mechanism to avoid conflict escalation, which could lead to social disruption and hence jeopardize cooperative activities. The high relatedness among individuals in the pack and the greater dependence of all members on cooperation in breeding and hunting may reduce the importance of 'relationship quality' as a mediating factor of POAs, although dominance relationships, which are directly linked to the risks of further conflicts, do play an important role.

  4. Measuring the impact of a public awareness campaign to increase Welfare Power of Attorney registrations in Scotland.

    Science.gov (United States)

    Levin, Kate A; Carson, Jill; Crighton, Emilia

    2017-07-01

    to measure the impact of the 'My Power of Attorney' media campaign on the number of new power of attorney (POA) registrations in Scotland. POA registrations in Scotland processed by the Office of the Public Guardian during January 2010 to June 2015. multilevel Poisson models for POA registrations nested by council and annual quarter were run using Markov chain Monte Carlo methods, adjusting for time, campaign (variable ranging between 0 and 5 dependent on intensity of campaign measured by the number of media platforms received) and offset term mid-year population estimate for those aged 25 years+/65 years+. POA registrations saw a reduction between 2010 and 2011 but overall, increased between 2010 and 2015. POA registrations rose by 33.3% in Glasgow City between 2013 and 2014, when the campaign began, while the rest of Scotland saw a rise of 17.3%. When the data were modelled, Relative Risk (RR) of a POA registration increased with increasing intensity of campaign, so that in an area in receipt of the full campaign was RR = 1.31 (1.28, 1.34) that of an area with no campaign. Between council variation persisted after adjustment for campaign (Variance = 0.041 (0.011)). during the period of the campaign, area-level increases in POA registrations were observed associated with the 'My Power of Attorney' timing and location, in an approximate dose-response relationship with campaign intensity, suggesting that this is likely to be due to the campaign that began in Glasgow City.

  5. Pasado y presente del uso de plantas silvestres con órganos subterráneos de almacenamiento comestibles en la Patagonia

    Directory of Open Access Journals (Sweden)

    Juan J. Ochoa

    2011-07-01

    Full Text Available El presente trabajo es la primara aproximación acerca del papel de las plantas con órganos de almacenamiento subterráneos comestibles (POAS en la Patagonia, desde una perspectiva temporal y espacial, al integrar datos etnohistóricos y etnográficos actuales ligados al uso de las POAS. El 75 % de las 54 fuentes analizadas mencionan el uso de POAS en la alimentación humana de la Patagonia. Las POAS silvestres comestibles registradas ascienden a 51 especies, siendo mayor el conjunto de POAS con raíces comestibles. La estepa y zonas ecotonales resultaron las de mayor riqueza de POAS, probablemente vinculado a adaptaciones ecológicas de éstas a la aridez en el primer caso, como a la alta diversidad relativa que presentan los ecotonos, en el segundo. El registro etnohistórico mostró discontinuidades marcadas, siendo pocas las especies presentes por más de un siglo, destacándose la continuidad documental de A. tuberosa desde el siglo XVIII al presente, así como la incorporación reciente de especies exóticas. Las fuentes etnohistóricas revisadas y su contraste con datos etnobotánicos recientes de campo sugieren dinamismo en los patrones de utilización, que a lo largo del tiempo han llevado al abandono del uso de las POAS en la práctica alimentaria de la Patagonia. Las singularidades encontradas respecto a lo temporal y espacial pueden vincularse tanto a los conocimientos locales y específicos desarrollados a lo largo del tiempo por los habitantes de la Patagonia, como también a las circunstancias sociopolíticas y académicas de cada una de las fuentes analizadas.

  6. pncA gene expression and prediction factors on pyrazinamide resistance in Mycobacterium tuberculosis.

    Science.gov (United States)

    Sheen, Patricia; Lozano, Katherine; Gilman, Robert H; Valencia, Hugo J; Loli, Sebastian; Fuentes, Patricia; Grandjean, Louis; Zimic, Mirko

    2013-09-01

    Mutations in the pyrazinamidase (PZAse) coding gene, pncA, have been considered as the main cause of pyrazinamide (PZA) resistance in Mycobacterium tuberculosis. However, recent studies suggest there is no single mechanism of resistance to PZA. The pyrazinoic acid (POA) efflux rate is the basis of the PZA susceptibility Wayne test, and its quantitative measurement has been found to be a highly sensitive and specific predictor of PZA resistance. Based on biological considerations, the POA efflux rate is directly determined by the PZAse activity, the level of pncA expression, and the efficiency of the POA efflux pump system. This study analyzes the individual and the adjusted contribution of PZAse activity, pncA expression and POA efflux rate on PZA resistance. Thirty M. tuberculosis strains with known microbiological PZA susceptibility or resistance were analyzed. For each strain, PZAse was recombinantly produced and its enzymatic activity measured. The level of pncA mRNA was estimated by quantitative RT-PCR, and the POA efflux rate was determined. Mutations in the pncA promoter were detected by DNA sequencing. All factors were evaluated by multiple regression analysis to determine their adjusted effects on the level of PZA resistance. Low level of pncA expression associated to mutations in the pncA promoter region was observed in pncA wild type resistant strains. POA efflux rate was the best predictor after adjusting for the other factors, followed by PZAse activity. These results suggest that tests which rely on pncA mutations or PZAse activity are likely to be less predictive of real PZA resistance than tests which measure the rate of POA efflux. This should be further analyzed in light of the development of alternate assays to determine PZA resistance. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Evidence that GABAergic neurons in the preoptic area of the rat brain are targets of 2,3,7,8-tetrachlorodibenzo-p-dioxin during development.

    Science.gov (United States)

    Hays, Linda E; Carpenter, Clifford D; Petersen, Sandra L

    2002-01-01

    Developmental exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) interferes with masculinization and defeminization of male sexual behaviors and gonadotropin release patterns. We previously demonstrated that the mRNA encoding the arylhydrocarbon receptor (AhR), a protein that mediates TCDD effects, is found in brain regions that control reproductive functions, most notably in the preoptic area (POA). The pattern of distribution of the AhR gene closely overlaps that of an enzyme necessary for Gamma-aminobutyric acid (GABA) synthesis, glutamic acid decarboxylase (GAD) 67. To test the hypothesis that GABAergic neurons in the POA are targets of TCDD during development, we used dual-label in situ hybridization histochemistry (ISHH) to co-localize GAD and AhR mRNAs in the region. In addition, we used ISHH to determine the effects of TCDD (1 microg/kg body weight, gestational day 15) on GAD 67 gene expression in POA regions in pups examined on postnatal day 3. We found that virtually all GABAergic neurons in the POA expressed the AhR gene. Furthermore, GAD 67 mRNA levels were higher in females than in males in the rostral POA/anteroventral periventricular nucleus (rPOA/AVPV) and in the rostral portion of the medial preoptic nucleus (MPN). TCDD abolished sex differences in the rPOA/AVPV but had no effect in the rostral MPN. In the caudal MPN, there were no sex differences in GAD 67 gene expression, but TCDD depressed expression specifically in males. Our findings demonstrate that GABAergic neurons in the brain are targets of TCDD and may mediate developmental effects of this contaminant on reproductive function. PMID:12060831

  8. The physical and chemical characteristics of marine primary organic aerosol: a review

    Directory of Open Access Journals (Sweden)

    B. Gantt

    2013-04-01

    Full Text Available Knowledge of the physical characteristics and chemical composition of marine organic aerosols is needed for the quantification of their effects on solar radiation transfer and cloud processes. This review examines research pertinent to the chemical composition, size distribution, mixing state, emission mechanism, photochemical oxidation and climatic impact of marine primary organic aerosol (POA associated with sea-spray. Numerous measurements have shown that both the ambient mass concentration of marine POA and size-resolved organic mass fraction of sea-spray aerosol are related to surface ocean biological activity. Recent studies have also indicated that fine mode (smaller than 200 nm in diameter marine POA can have a size distribution independent from sea-salt, while coarse mode aerosols (larger than 1000 nm in diameter are more likely to be internally mixed with sea-salt. Modelling studies have estimated global submicron marine POA emission rates of ~10 ± 5 Tg yr−1, with a considerable fraction of these emissions occurring over regions most susceptible to aerosol perturbations. Climate studies have found that marine POA can cause large local increases in the cloud condensation nuclei concentration and have a non-negligible influence on model assessments of the anthropogenic aerosol forcing of climate. Despite these signs of climate-relevance, the source strength, chemical composition, mixing state, hygroscopicity, cloud droplet activation potential, atmospheric aging and removal of marine POA remain poorly quantified. Additional laboratory, field, and modelling studies focused on the chemistry, size distribution and mixing state of marine POA are needed to better understand and quantify their importance.

  9. Lubricating oil dominates primary organic aerosol emissions from motor vehicles.

    Science.gov (United States)

    Worton, David R; Isaacman, Gabriel; Gentner, Drew R; Dallmann, Timothy R; Chan, Arthur W H; Ruehl, Christopher; Kirchstetter, Thomas W; Wilson, Kevin R; Harley, Robert A; Goldstein, Allen H

    2014-04-01

    Motor vehicles are major sources of primary organic aerosol (POA), which is a mixture of a large number of organic compounds that have not been comprehensively characterized. In this work, we apply a recently developed gas chromatography mass spectrometry approach utilizing "soft" vacuum ultraviolet photoionization to achieve unprecedented chemical characterization of motor vehicle POA emissions in a roadway tunnel with a mass closure of >60%. The observed POA was characterized by number of carbon atoms (NC), number of double bond equivalents (NDBE) and degree of molecular branching. Vehicular POA was observed to predominantly contain cycloalkanes with one or more rings and one or more branched alkyl side chains (≥80%) with low abundances of n-alkanes and aromatics (lubricating oil. The gas chromatography retention time data indicates that the cycloalkane ring structures are most likely dominated by cyclohexane and cyclopentane rings and not larger cycloalkanes. High molecular weight combustion byproducts, that is, alkenes, oxygenates, and aromatics, were not present in significant amounts. The observed carbon number and chemical composition of motor vehicle POA was consistent with lubricating oil being the dominant source from both gasoline and diesel-powered vehicles, with an additional smaller contribution from unburned diesel fuel and a negligible contribution from unburned gasoline.

  10. Increasing the benefits and reducing the harms of prescription opioid analgesics.

    Science.gov (United States)

    Hallinan, Richard; Osborn, Mary; Cohen, Milton; Dobbin, Malcolm; Wodak, Alex

    2011-05-01

    Consumption of prescription opioid analgesics (POAs) in Australia has increased steadily in recent years, raising concerns of increasing harms including overdose and dependence, as has occurred in the USA. Exposition of the Royal Australasian College of Physicians Prescription Opioid Policy with reference to the published literature, drawing out principles for harm reduction for psychoactive pharmaceutical drugs. Complex professional, patient, regulatory and market factors influence health professionals balancing the benefits and harms of POAs. Owing to the potential for diversion, overlapping markets probably exist for pharmaceutical opioids used for populations with cancer pain, chronic non-cancer pain, and people dependent on pharmaceutical and illicit opioids (including those needing opioid substitution treatment). Attempts to reduce or restrict supply in one area may increase demand in others. There is a need to consider new harm reduction strategies for people with problematic pharmaceutical opioid use. These people are demographically not well characterised, and may be distinct from the more familiar population of injection drug users. Harm reduction is a valid approach for POAs. However, the role of health professionals as gatekeepers of opioid supply, the need to optimise health benefits of POAs, and the likely interplay of complex market forces among populations consuming opioids have no close parallel in harm reduction for other substances. This poses fundamentally different challenges. Reducing inappropriate supply and demand for POAs while maximising their benefits and minimising their harms may improve health outcomes. © 2011 Australasian Professional Society on Alcohol and other Drugs.

  11. Pd-Cu/poly(o-Anisidine) nanocomposite as an efficient catalyst for formaldehyde oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Hosseini, Sayed Reza, E-mail: r.hosseini@umz.ac.ir [Nanochemistry Research Laboratory, Faculty of Chemistry, University of Mazandaran, 47416-95447 Babolsar (Iran, Islamic Republic of); Raoof, Jahan-Bakhsh [Department of Analytical Chemistry, Faculty of Chemistry, University of Mazandaran, 47416-95447 Babolsar (Iran, Islamic Republic of); Ghasemi, Shahram; Gholami, Zahra [Nanochemistry Research Laboratory, Faculty of Chemistry, University of Mazandaran, 47416-95447 Babolsar (Iran, Islamic Republic of)

    2016-08-15

    Highlights: • o-Anisidine monomer was electro-polymerized at the pCPE surface in acid medium. • Palladium/copper NPs were prepared by galvanic replacement method at the POA/pCPE. • Pd-Cu NPs showed excellent electrocatalytic activity towards formaldehyde oxidation. • The bimetallic Pd-Cu NPs/POA nanocomposite showed satisfactory long-term stability. - Abstract: In this work, for the first time, the electrocatalytic oxidation of formaldehyde in 0.5 M sulfuric acid solution at spherical bimetallic palladium-copper nanoparticles (Pd-Cu NPs) deposited on the poly (o-Anisidine) film modified electrochemically pretreated carbon paste electrode (POA/pCPE) has been investigated. Highly porous POA film prepared by electropolymerization onto the pCPE was used as a potent support for deposition of the Pd-Cu NPs. The Pd-Cu NPs were prepared through spontaneous and irreversible reaction via galvanic replacement between Pd{sup II} ions and the Cu{sup 0} particles. The prepared Pd-Cu NPs were characterized by scanning electron microscopy, energy dispersive spectroscopy and electrochemical methods. The obtained results showed that the utilization of Cu nanoparticles and pretreatment technique enhances the electrocatalytic activity of the modified electrode towards formaldehyde oxidation. The influence of several parameters on formaldehyde oxidation as well as stability of the Pd-Cu/POA/pCPE has been investigated.

  12. Coraco- or Costoclavicular Paraosteoarthropathies in Patients with Severe Central Neurological Disorders

    Energy Technology Data Exchange (ETDEWEB)

    Lacout, A.; Mompoint, D.; Perrier, Y.; Vallee, C.A.; Carlier, R.Y. (Service de Radiologie, Hopital Raymond Poincare, Garches (France))

    2008-03-15

    Background: Paraosteoarthropathy (POA) is a frequent disabling orthopedic complication after severe central neurological impairment. The hip is the most frequently affected joint (32.1%) followed by the elbow and the shoulder (25%). Purpose: To evaluate coraco- and costoclavicular paraosteoarthropathy in patients with severe central neurological disorders. Material and Methods: We report a series of five consecutive patients with severe central neurological disorders who developed a POA of the clavicular region (coracoclavicular or costoclavicular POA). Every patient underwent a clinical, radiological, and computed tomographic (CT) examination of the shoulder region. Results: Four patients had a history of traumatic brain injury (TBI), and one an acute disseminated encephalomyelitis (ADEM). They developed POA of the clavicular region, although not around the glenohumeral joint. The patients complained of shoulder pain and of moderate limitation of movements. Radiological and CT examinations showed the presence of a bony formation in the coracoclavicular space in four cases and extending from the clavicle to the first rib around the costoclavicular joint in one case. Conclusion: In patients with severe brain lesions suffering from shoulder pain and moderate limitation of joint movements, POAs of the clavicular region are rare but should be considered

  13. Screening immigrants for tuberculosis in Newcastle upon Tyne.

    Science.gov (United States)

    Lavender, M

    1997-09-01

    Successive national guidelines on the control of tuberculosis in the United Kingdom have included recommendations for screening immigrants coming from countries with a high prevalence of tuberculosis. As there has been only one other study on the process and outcome of screening immigrants at a district level the aim of this study was to assess the contribution of screening immigrants to the control of tuberculosis in Newcastle. The Port of Arrival (POA) forms were used to identify all new immigrants for screening in Newcastle during 1993. The Family Health Services Authority (FHSA) register was used to identify additional new immigrants from the Indian sub-continent. For all new immigrants identified by the POA forms and FHSA register, hospital and practice records were reviewed for evidence of screening and its outcome up to the end of 1994. There were 252 POA forms in 1993, 100 of which were for immigrants from the Indian sub-continent. This represents less than a third of all new immigrants from the Indian sub-continent. Of all immigrants identified by POA forms, 99 (39 per cent) had been screened. This resulted in the detection of one active case of tuberculosis. The POA system alone is inadequate for identifying immigrants for screening. The published evidence on screening immigrants for tuberculosis suggests that the system does not work well and the yield of new cases is low. To assess the effectiveness of screening immigrants a national audit is needed.

  14. Sensory modulation of the medial preoptic area neuronal activity by dorsal penile nerve stimulation in rats.

    Science.gov (United States)

    Mallick, H N; Manchanda, S K; Kumar, V M

    1994-03-01

    The study was aimed at finding out the influence exerted by the genital afferents on the medial preoptic area (mPOA), which plays a pivotal role in the regulation of male sex behavior. To fulfil this objective, the effects of stimulation of the dorsal penile nerve (DPN) on the activity of 82 mPOA neurons were studied. The base line firing rates of the mPOA neurons, studied by extracellular recording, ranged between 0.5 and 38.5 Hz (mean 7.18 +/- 7.91). The stimulation of the DPN (20 Hz, 0.4 msec. 70 microA) influenced 79.69% of the neurons studied. Though increased firing was the predominant influence produced (50%), decreased firing was also seen in a few (29.69%). The excited and inhibited neurons were randomly distributed within the mPOA. Neurons located in the lateral and posterior hypothalamus were not affected by the DPN stimulation. The stimulation parameters used in this study did not produce any change in the systemic arterial pressure and heart rate. The results provide electrophysiological evidence of afferent inputs from the male sex organ to the mPOA, which is an important area controlling male sex behavior.

  15. FIXING A BASAL BERRIASIAN AND JURASSIC-CRETACEOUS (J-K BOUNDARY - IS THERE PERHAPS SOME LIGHT AT THE END OF THE TUNNEL?

    Directory of Open Access Journals (Sweden)

    WILLIAM A.P. WIMBLEDON

    2011-07-01

    Full Text Available Our tentative proposal is that several biological markers have potential to help define any putative boundary in the traditional basal Berriasian interval. That is, between the base of the Berriasella jacobi Subzone and the base of the Pseudosubplanites grandis Subzone, and therefore straddling the base of magnetozone M18r.  Promising micropalaeontological markers are the FADs of Nannoconus steinmannii minor and N. kamptneri minor, plus the base of the Calpionella alpina Zone, and the bloom(s of Calpionella alpina and Crassicollaria parvula.  The testing and calibration of this constraining event-matrix in the most complete and fossiliferous sections is our task for the near future. 

  16. Commenti a nomi friulani di piante raccolti nell’aslef IV. (*

    Directory of Open Access Journals (Sweden)

    Giovan Battista Pellegrini

    1974-12-01

    Full Text Available [ASLEF I, 597, carta 1200] Il Leontopodium Alpinum Cass., stella alpina, e una composita alta 5/25 em., lanosa, con foglie lineari-lanceolate grigioverdastre di sopra e cenerino-tomentose di sotto. E'assai ricercata ed è venuta ad indicare il »simbolo dell'alpinismo«; ha il suo centro di diffusione nei grandi altipiani dell'Asia Centrale e sud-occidentale ed è un elemento delle steppe siberiane. Cresce sugli alti pascoli dei monti calcarei, ma non è rara su suolo siliceo, rupestre. In Friuli è frequente nella zona subalpina e alpina, da 1100 m. (cas. Palasecca a 2000/2200 m. (cas. Bordaglia, M. Cretabianca, Pleros; più rara nella regione montana e submontana, Gortani II, 438 (che cita i nomi dial. simprivzv di mont e stele alpine.

  17. Electrophysiological characterization of male goldfish (Carassius auratus ventral preoptic area neurons receiving olfactory inputs

    Directory of Open Access Journals (Sweden)

    Wudu E. Lado

    2014-06-01

    Full Text Available Chemical communication via sex pheromones is critical for successful reproduction but the underlying neural mechanisms are not well-understood. The goldfish is a tractable model because sex pheromones have been well-characterized in this species. We used male goldfish forebrain explants in vitro and performed whole-cell current clamp recordings from single neurons in the ventral preoptic area (vPOA to characterize their membrane properties and synaptic inputs from the olfactory bulbs (OB. Principle component and cluster analyses based on intrinsic membrane properties of vPOA neurons (N = 107 revealed five (I-V distinct cell groups. These cells displayed differences in their input resistance (Rinput: I II = IV > III = V. Evidence from electrical stimulation of the OB and application of receptor antagonists suggests that vPOA neurons receive monosynaptic glutamatergic inputs via the medial olfactory tract, with connectivity varying among neuronal groups [I (24%, II (40%, III (0%, IV (34% and V (2%].

  18. Increased risk of revision in patients with non-traumatic femoral head necrosis

    DEFF Research Database (Denmark)

    Bergh, Camilla; Fenstad, Ann M; Furnes, Ove

    2014-01-01

    is not associated with poor outcome. We compared the risk of revision after operation with THA due to FHN or POA in the Nordic Arthroplasty Register Association (NARA) database including Denmark, Finland, Norway, and Sweden. Patients and methods - 427,806 THAs performed between 1995 and 2011 were included......Background and purpose - Previous studies of patients who have undergone total hip arthroplasty (THA) due to femoral head necrosis (FHN) have shown an increased risk of revision compared to cases with primary osteoarthritis (POA), but recent studies have suggested that this procedure....... The relative risk of revision for any reason, for aseptic loosening, dislocation, deep infection, and periprosthetic fracture was studied before and after adjustment for covariates using Cox regression models. Results - 416,217 hips with POA (mean age 69 (SD 10), 59% females) and 11,589 with FHN (mean age 65...

  19. Evaluation of chemical transport model predictions of primary organic aerosol for air masses classified by particle-component-based factor analysis

    Science.gov (United States)

    Stroud, C. A.; Moran, M. D.; Makar, P. A.; Gong, S.; Gong, W.; Zhang, J.; Slowik, J. G.; Abbatt, J. P. D.; Lu, G.; Brook, J. R.; Mihele, C.; Li, Q.; Sills, D.; Strawbridge, K. B.; McGuire, M. L.; Evans, G. J.

    2012-02-01

    Observations from the 2007 Border Air Quality and Meteorology Study (BAQS-Met 2007) in southern Ontario (ON), Canada, were used to evaluate Environment Canada's regional chemical transport model predictions of primary organic aerosol (POA). Environment Canada's operational numerical weather prediction model and the 2006 Canadian and 2005 US national emissions inventories were used as input to the chemical transport model (named AURAMS). Particle-component-based factor analysis was applied to aerosol mass spectrometer measurements made at one urban site (Windsor, ON) and two rural sites (Harrow and Bear Creek, ON) to derive hydrocarbon-like organic aerosol (HOA) factors. Co-located carbon monoxide (CO), PM2.5 black carbon (BC), and PM1 SO4 measurements were also used for evaluation and interpretation, permitting a detailed diagnostic model evaluation. At the urban site, good agreement was observed for the comparison of daytime campaign PM1 POA and HOA mean values: 1.1 μg m-3 vs. 1.2 μg m-3, respectively. However, a POA overprediction was evident on calm nights due to an overly-stable model surface layer. Biases in model POA predictions trended from positive to negative with increasing HOA values. This trend has several possible explanations, including (1) underweighting of urban locations in particulate matter (PM) spatial surrogate fields, (2) overly-coarse model grid spacing for resolving urban-scale sources, and (3) lack of a model particle POA evaporation process during dilution of vehicular POA tail-pipe emissions to urban scales. Furthermore, a trend in POA bias was observed at the urban site as a function of the BC/HOA ratio, suggesting a possible association of POA underprediction for diesel combustion sources. For several time periods, POA overprediction was also observed for sulphate-rich plumes, suggesting that our model POA fractions for the PM2.5 chemical speciation profiles may be too high for these point sources. At the rural Harrow site

  20. The loss of efficiency caused by agents' uncoordinated routing in transport networks.

    Directory of Open Access Journals (Sweden)

    Zhongzhi Xu

    Full Text Available Large-scale daily commuting data were combined with detailed geographical information system (GIS data to analyze the loss of transport efficiency caused by drivers' uncoordinated routing in urban road networks. We used Price of Anarchy (POA to quantify the loss of transport efficiency and found that both volume and distribution of human mobility demand determine the POA. In order to reduce POA, a small number of highways require considerable decreases in traffic, and their neighboring arterial roads need to attract more traffic. The magnitude of the adjustment in traffic flow can be estimated using the fundamental measure traffic flow only, which is widely available and easy to collect. Surprisingly, the most congested roads or the roads with largest traffic flow were not those requiring the most reduction of traffic. This study can offer guidance for the optimal control of urban traffic and facilitate improvements in the efficiency of transport networks.

  1. The role of motivation and reward neural systems in vocal communication in songbirds

    Science.gov (United States)

    Riters, Lauren V.

    2012-01-01

    Many vertebrates are highly motivated to communicate, suggesting that the consequences of communication may be rewarding. Past studies show that dopamine and opioids in the medial preoptic nucleus (mPOA) and ventral tegmental area (VTA) play distinct roles in motivation and reward. In songbirds, multiple lines of recent evidence indicate that the roles of dopamine and opioid activity in mPOA and VTA in male birdsong differ depending upon whether song is used to attract females (sexually-motivated) or is produced spontaneously (undirected). Evidence is reviewed supporting the hypotheses that 1) mPOA and VTA interact to influence the context in which a male sings, 2) distinct patterns of dopamine activity underlie the motivation to produce sexually-motivated and undirected song, 3) sexually-motivated communication is externally reinforced by opioids released as part of social interactions, and 4) undirected communication is facilitated and rewarded by immediate opioid release linked to the act of singing. PMID:22569510

  2. Plan de acción ambiental para el municipio de Corn Island

    Directory of Open Access Journals (Sweden)

    Romer Altamirano Guerrero

    2004-02-01

    Full Text Available El desorden territorial, producto del inadecuado uso actual del suelo, el irracional de los recursos naturales y el deterioro de la calidad ambiental del Municipio de Corn Island, son los puntos de partida del presente estudio que consiste en la elaboración del Plan de ordenamiento Ambiental del Municipio (POA de Corn Island. Dicho POA se enmarca en la estrategia del Plan de Acción para el manejo de los recursos naturales del Municipio de Corn Island, realizado en 1999, y posteriormente impulsado por la Unidad de Zonas Costeras y Humedales de la Dirección de Biodiversidad y Recursos Naturales del Ministerio del Ambiente y los Recursos Naturales (MARENA y la Alcaldía de Corn Island. El Plan de Acción define como una de sus prioridades, estructurar el POA para el Municipio.

  3. AcEST: DK955410 [AcEST

    Lifescience Database Archive (English)

    Full Text Available e 56.9) Link to BlastX Result : Swiss-Prot sp_hit_id O24339 Definition sp|O24339|CATA_SOLAP... E Sequences producing significant alignments: (bits) Value sp|O24339|CATA_SOLAP ...na GN=CAT1... 79 5e-15 >sp|O24339|CATA_SOLAP Catalase OS=Soldanella alpina PE=2 SV=1 Length = 492 Score = 90

  4. AcEST: DK955964 [AcEST

    Lifescience Database Archive (English)

    Full Text Available VGIPQDYRHMDGFGVNTYTLINKA 216 Query: 541 GKTTYVKFHWKPTC 582 GK YVKFHWK TC Sbjct: 217 GKAVYVKFHWKTTC 230 >sp|O24339|CATA_SOLAP...g significant alignments: (bits) Value sp|O48560|CATA3_SOYBN Catalase-3 OS=Glycine max GN=CAT3 PE=2 SV=1 387... e-107 sp|O24339|CATA_SOLAP Catalase OS=Soldanella alpina PE=2 SV=1 385 e-107 sp|

  5. AcEST: DK962141 [AcEST

    Lifescience Database Archive (English)

    Full Text Available sp|P48406|CHS5_SOYBN Chalcone synthase 5 OS=Glycine max GN=CHS5 ... 259 9e-69 sp|Q9FSB7|CHS3_RUTGR Chalcone synthase 3 OS=Ruta...s alpina GN=CHS P... 255 2e-67 sp|Q9FSB9|CHS1_RUTGR Chalcone synthase 1 OS=Ruta graveolens GN=C... 254 2e-67

  6. O IDRC no Brasil

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

    níveis primários do cuidado da saúde poderá levar a sistemas de saúde universais melhor integrados. Os resultados deverão subven- cionar os atuais debates levados adiante na. América Latina a respeito de políticas de saúde. □ Cadeiras de Pesquisa Internacional do IDRC. Alpina Begossi, Universidade Estadual de.

  7. Dynamics of Chytridiomycosis during the Breeding Season in an Australian Alpine Amphibian

    OpenAIRE

    Brannelly, Laura A.; David A Hunter; Daniel Lenger; Scheele, Ben C.; Skerratt, Lee F.; Lee Berger

    2015-01-01

    Understanding disease dynamics during the breeding season of declining amphibian species will improve our understanding of how remnant populations persist with endemic infection, and will assist the development of management techniques to protect disease-threatened species from extinction. We monitored the endangered Litoria verreauxii alpina (alpine treefrog) during the breeding season through capture-mark-recapture (CMR) studies in which we investigated the dynamics of chytridiomycosis in r...

  8. A Working Module for the Neurovascular Unit in the Sexually Dimorphic Nucleus of the Preoptic Area.

    Science.gov (United States)

    He, Zhen; Cui, Li; Ferguson, Sherry A; Paule, Merle G

    2018-01-01

    The neurovascular unit (NVU) can be conceptualized as a functional entity consisting of neurons, astrocytes, pericytes, and endothelial and smooth muscle cells that operate in concert to affect blood flow to a very circumscribed area. Although we are currently in a "golden era" of bioengineering, there are, as yet, no living NVUs-on-a-chip modules available and the development of a neural chip that would mimic NVUs is a seemingly lofty goal. The sexually dimorphic nucleus of the preoptic area (SDN-POA) is a tiny brain structure (between 0.001~0.007 mm 3 in rats) with an assessable biological function (i.e., male sexual behavior). The present effort was undertaken to determine whether there are identifiable NVUs in the SDN-POA by assessing its vasculature relative to its known neural components. First, a thorough and systematic review of thousands of histologic and immunofluorescent images from 201 weanling and adult rats was undertaken to define the characteristics of the vessels supplying the SDN-POA: its primary supply artery/arteriole and capillaries are physically inseparable from their neural elements. A subsequent immunofluorescent study targeting α-smooth muscle actin confirmed the identity of an artery/arteriole supplying the SDN-POA. In reality, the predominant components of the SDN-POA are calbindin D28k-positive neurons that are comingled with tyrosine hydroxylase-positive projections. Finally, a schematic of an SDN-POA NVU is proposed as a working model of the basic building block of the CNS. Such modules could serve the study of neurovascular mechanisms and potentially inform the development of next generation bioengineered neural transplants, i.e., the construct of an NVU neural chip.

  9. Tendência da mortalidade por aids segundo características sociodemográficas no Rio Grande do Sul e em Porto Alegre: 2000-2011

    Directory of Open Access Journals (Sweden)

    Ana Paula da Cunha

    Full Text Available Resumo OBJETIVO: analisar a tendência da mortalidade por aids no Rio Grande do Sul (RS e em Porto Alegre (POA segundo características sociodemográficas, no período 2000-2011. MÉTODOS: estudo ecológico de série temporal, sobre taxas de mortalidade por aids; utilizou-se o modelo de Prais-Winsten. RESULTADOS: a taxa padronizada de mortalidade por aids apresentou tendência estacionária no RS (1,3%; IC95% -0,6;6,7 e em POA (-0,3%; IC95% -5,1;3,9; houve tendência crescente entre as mulheres no RS (4,1%; IC95% 3,0;5,3 e em POA (2,7%; IC95% 1,8;3,5, na raça/cor parda no RS (4,5%; IC95% 1,9;7,2 e em POA (4,6%; IC95% 1,5;7,9, e nas faixas etárias de 40-49 no RS (4,0%; IC95% 1,3;6,7, 50-59 no RS (5,8%; IC95% 1,9;9,9 e em POA (6,0%; IC95% 2,1;9,9, e >60 anos no RS (4,0%; IC95% 1,1;6,9. CONCLUSÃO: no RS e em POA, a mortalidade por aids aumentou nas mulheres, entre indivíduos de raça/cor parda e nas idades mais avançadas.

  10. A regional analysis of estrogen binding to hypothalamic cell nuclei in relation to masculinization and defeminization.

    Science.gov (United States)

    Nordeen, E J; Yahr, P

    1983-05-01

    Gonadal steroids masculinize and defeminize neuroendocrine development, including behavior. Defeminization makes males less sensitive than females to estrogen for showing female sexual behavior and cyclic gonadotropin secretion. Masculinization makes males more sensitive than females to estrogen for showing male sexual behavior. Thus masculinization and defeminization produce opposite effects on estrogen sensitivity. To study the relationship between estrogen sensitivity and estrogen binding, we studied sex differences in estrogen binding to hypothalamic cell nuclei on a regional and temporal basis. We measured the amount of estradiol (E2) bound to cell nuclei in the preoptic area (POA), mediobasal hypothalamus (MBH), corticomedial amygdala, and cortex of gonadectomized male and female rats 30 and 60 min after [3H]E2 was injected intravenously. In the MBH, males consistently bound less E2 than females did. In the POA, males bound less E2 than females after 60 min, but they bound more E2 than females after 30 min. Decreased estrogen binding in the MBH may underlie defeminized sexual behavior. Similarly, decreased estrogen binding in the POA at 60 min may be a correlate of defeminized gonadotropin secretion, whereas increased estrogen binding in the POA at 30 min may be a correlate of masculinized sexual behavior. To test the hypothesis that decreased estrogen binding in the MBH and POA are correlates of defeminization, we measured E2 binding at 60 min in female rats in which masculinization and defeminization were manipulated independently. Defeminization decreased E2 binding to cell nuclei in both the POA and MBH to the level seen in males at this time point. Masculinization had no effect at this time point. The data suggest that sex differences in E2 binding to hypothalamic cell nuclei correlate reliably with sex differences in estrogen sensitivity even though masculinization and defeminization produce opposing effects on these parameters.

  11. Model evaluation of marine primary organic aerosol emission schemes

    Directory of Open Access Journals (Sweden)

    B. Gantt

    2012-09-01

    Full Text Available In this study, several marine primary organic aerosol (POA emission schemes have been evaluated using the GEOS-Chem chemical transport model in order to provide guidance for their implementation in air quality and climate models. These emission schemes, based on varying dependencies of chlorophyll a concentration ([chl a] and 10 m wind speed (U10, have large differences in their magnitude, spatial distribution, and seasonality. Model comparison with weekly and monthly mean values of the organic aerosol mass concentration at two coastal sites shows that the source function exclusively related to [chl a] does a better job replicating surface observations. Sensitivity simulations in which the negative U10 and positive [chl a] dependence of the organic mass fraction of sea spray aerosol are enhanced show improved prediction of the seasonality of the marine POA concentrations. A top-down estimate of submicron marine POA emissions based on the parameterization that compares best to the observed weekly and monthly mean values of marine organic aerosol surface concentrations has a global average emission rate of 6.3 Tg yr−1. Evaluation of existing marine POA source functions against a case study during which marine POA contributed the major fraction of submicron aerosol mass shows that none of the existing parameterizations are able to reproduce the hourly-averaged observations. Our calculations suggest that in order to capture episodic events and short-term variability in submicron marine POA concentration over the ocean, new source functions need to be developed that are grounded in the physical processes unique to the organic fraction of sea spray aerosol.

  12. Evaluating simulated primary anthropogenic and biomass burning organic aerosols during MILAGRO: implications for assessing treatments of secondary organic aerosols

    Directory of Open Access Journals (Sweden)

    J. Fast

    2009-08-01

    Full Text Available Simulated primary organic aerosols (POA, as well as other particulates and trace gases, in the vicinity of Mexico City are evaluated using measurements collected during the 2006 Megacity Initiative: Local and Global Research Observations (MILAGRO field campaigns. Since the emission inventories, transport, and turbulent mixing will directly affect predictions of total organic matter and consequently total particulate matter, our objective is to assess the uncertainties in predicted POA before testing and evaluating the performance of secondary organic aerosol (SOA treatments. Carbon monoxide (CO is well simulated on most days both over the city and downwind, indicating that transport and mixing processes were usually consistent with the meteorological conditions observed during MILAGRO. Predicted and observed elemental carbon (EC in the city was similar, but larger errors occurred at remote locations since the overall CO/EC emission ratios in the national emission inventory were lower than in the metropolitan emission inventory. Components of organic aerosols derived from Positive Matrix Factorization of data from several Aerodyne Aerosol Mass Spectrometer instruments deployed both at ground sites and on research aircraft are used to evaluate the model. Modeled POA was consistently lower than the measured organic matter at the ground sites, which is consistent with the expectation that SOA should be a large fraction of the total organic matter mass. A much better agreement was found when modeled POA was compared with the sum of "primary anthropogenic" and "biomass burning" components derived from Positive Matrix Factorization (PMF on most days, especially at the surface sites, suggesting that the overall magnitude of primary organic particulates released was reasonable. However, simulated POA from anthropogenic sources was often lower than "primary anthropogenic" components derived from PMF, consistent with two recent reports that these emissions

  13. Species identification, host range and diversity of Cecidophyopsis mites (Acari: Trombidiformes) infesting Ribes in Latvia.

    Science.gov (United States)

    Stalažs, Arturs; Moročko-Bičevska, Inga

    2016-06-01

    Cecidophyopsis mites are important pests in all cultivation regions of Ribes causing bud galls and sterility. Despite their economic importance, the knowledge on Cecidophyopsis species infesting Ribes in various areas of the world is still deficient. The present study was carried out to identify Cecidophyopsis species occurring in Latvia on cultivated and wild Ribes, to assess their host range and gain insight into the genetic diversity of these insufficiently studied pests by use of multiplex PCR, rDNA sequences and morphological characters. Cecidophyopsis alpina, C. aurea, C. spicata and C. selachodon were detected to occur in all surveyed habitats. For the first time, C. alpina was identified on blackcurrants and redcurrants, and C. aurea on redcurrants, blackcurrants and alpine currants. The presence of C. ribis was not confirmed with molecular tools during this study. Phylogenetic analyses confirmed the presence of four Cecidophyopsis species identified by multiplex PCR. A close phylogenetic relatedness was found for C. aurea and C. alpina, and for C. ribis and C. spicata highlighting the necessity for additional studies. Our findings suggest a need to consider also other Cecidophyopsis species besides C. ribis in breeding programs for host resistance to mites.

  14. Tethyan calpionellids in the Neuquén Basin (Argentine Andes), their significance in defining the Jurassic/Cretaceous boundary and pathways for Tethyan-Eastern Pacific connections

    Science.gov (United States)

    López-Martínez, Rafael; Aguirre-Urreta, Beatriz; Lescano, Marina; Concheyro, Andrea; Vennari, Verónica; Ramos, Victor A.

    2017-10-01

    The study of calpionellid distribution in the well-documented Las Loicas section of the Vaca Muerta Formation in the Neuquén Basin, Argentine Andes, allows the recognition of the upper part of the Crassicollaria Zone and the lower part of Calpionella Zone across the Jurassic/Cretaceous boundary. The Crassicollaria Zone, Colomi Subzone (Upper Tithonian) is composed of Calpionella alpina Lorenz, Crassicollaria colomi Doben, Crassicollaria parvula Remane, Crassicollaria massutiniana (Colom), Crassicollaria brevis Remane, Tintinnopsella remanei (Borza) and Tintinnopsella carpathica (Murgeanu and Filipescu). The Calpionella Zone, Alpina Subzone (Lower Berriasian) is indicated by the explosion of the small and globular form of Calpionella alpina dominating over very scarce Crassicollaria massutiniana. The FAD of Nannoconus wintereri can be clearly correlated with the upper part of Crassicollaria Zone and the FAD of Nannoconus kamptneri minor with the Calpionella Zone. Additional studies are necessary to establish a more detailed calpionellid biozonation and its correlation with other fossil groups. The present work confirms similar calpionellid bioevents in westernmost Tethys (Cuba and Mexico) and the Andean region, strengthening the Paleo-Pacific-Tethyan connections through the Hispanic Corridor already known from other fossil groups.

  15. Máquina de Aspectos: un enfoque alternativo para la implementación de aspectos.

    OpenAIRE

    Gesto, Esteban; Hallar, Karim; Casas, Sandra

    2006-01-01

    La Programación Orientada a Aspectos (POA) es un nuevo paradigma de programación que propone mecanismos para soportar la separación de los aspectos no funcionales de los sistemas software. Una herramienta POA consiste en tres componentes principales: un lenguaje de programación base, un lenguaje de programación orientado a aspectos y un tejedor de aspectos (weaver). El presente trabajo propone un enfoque alternativo para la implementación de aspectos basado en la especificación de los mism...

  16. Differential sensitivity of porcine endogenous retrovirus to APOBEC3-mediated inhibition.

    Science.gov (United States)

    Park, Sung-Han; Kim, Jin Ha; Jung, Yong-Tae

    2015-08-01

    Pigs are considered to be suitable xenotransplantation organ donors. However, the risk of pathogen transmission from pigs to humans is a major concern in the transplantation of porcine tissues. The porcine endogenous retroviruses (PERVs) PERV-A, PERV-A/C, and PERV-B can infect human cells, but PERV-C is an ecotropic virus infecting only pig cells. Thus, several strategies have been proposed to reduce PERV transmission in xenograft recipients. Human APOBEC3G (huA3G) is a single-strand DNA cytosine deaminase, which inactivates the coding capacity of the virus by deamination of cDNA cytosines to uracils. This reaction occurs within the (-) DNA strand during reverse transcription, resulting in a G-to-A mutation in the (+) strand. While recent data have shown that PERV-B is severely inhibited by huA3G and porcine A3Z2-Z3 (poA3F) in a pseudotype assay, little is known about PERV-C. Here, we compare the antiretroviral activities of huA3G, huA3F and poA3Z2-Z3 against PERV-C. Our data show that APOBEC3 was packaged into PERV-C particles and inhibited PERV-C replication in a dose-dependent manner. PERV-C infectivity was strongly inhibited by poA3Z2-Z3, but it did not markedly reduce PERV-B infectivity. This suggests that PERV-C Gag interacts efficiently with poA3Z2-Z3. In addition, we constructed stably huA3G- and poA3Z2-Z3-expressing 293-PERV-PK-CIRCE cells (human 293 cells infected with PK15-derived PERVs) to examine whether PERV is resistant to poA3Z2-Z3 in a virus-spreading assay. The stably expressed huA3G and poA3Z2-Z3 were more packaging-competent than transiently expressed APOBEC3 proteins. These results suggest that poA3Z2-Z3 can inhibit PERV replication in a pseudotype assay as well as in a virus-spreading assay.

  17. Use and Nonmedical Use of Prescription Opioid Analgesics in the General Population of Canada and Correlations with Dispensing Levels in 2009

    Directory of Open Access Journals (Sweden)

    Kevin D Shield

    2013-01-01

    Full Text Available BACKGROUND: In Canada, harm from nonmedical prescription opioid analgesic (POA use (NMPOU has increased in recent years; however, there are limitations to the current estimates of NMPOU. The 2009 Canadian Alcohol and Drug Use Monitoring Survey presents an opportunity to produce more accurate estimates of NMPOU.

  18. Response of Young Apple Trees to Grass and Irrigation

    Science.gov (United States)

    Ground covers and irrigation are important components of orchard floor management systems that affect fruit tree vigor and productivity. Three experiments were conducted in a greenhouse to determine the relative water use of candidate ground covers (roughstalk bluegrass (RB, Poa trivialis), Chewing...

  19. Nonclassical Mechanisms of Progesterone Action in the Brain: I. Protein Kinase C Activation in the Hypothalamus of Female Rats

    Science.gov (United States)

    Balasubramanian, Bhuvana; Portillo, Wendy; Reyna, Andrea; Chen, Jian Zhong; Moore, Anthony N.; Dash, Pramod K.; Mani, Shaila K.

    2008-01-01

    The modulation of gene regulation by progesterone (P) and its classical intracellular regulation by progestin receptors in the brain, resulting in alterations in physiology and behavior has been well studied. The mechanisms mediating the short latency effects of P are less well understood. Recent studies have revealed rapid nonclassical signaling action of P involving the activation of intracellular signaling pathways. We explored the involvement of protein kinase C (PKC) in P-induced rapid signaling in the ventromedial nucleus of the hypothalamus (VMN) and preoptic area (POA) of the rat brain. Both the Ca2+-independent (basal) PKC activity representing the activation of PKC by the in vivo treatments and the Ca+2-dependent (total) PKC activity assayed in the presence of exogenous cofactors in vitro were determined. A comparison of the two activities demonstrated the strength and temporal status of PKC regulation by steroid hormones in vivo. P treatment resulted in a rapid increase in basal PKC activity in the VMN but not the POA. Estradiol benzoate priming augmented P-initiated increase in PKC basal activity in both the VMN and POA. These increases were inhibited by intracerebroventricular administration of a PKC inhibitor administered 30 min prior to P. The total PKC activity remained unchanged demonstrating maximal PKC activation within 30 min in the VMN. In contrast, P regulation in the POA significantly attenuated total PKC activity ± estradiol benzoate priming. These rapid changes in P-initiated PKC activity were not due to changes in PKC protein levels or phosphorylation status. PMID:18617608

  20. Formula Derivation and Usage in the Rational Selection of ...

    African Journals Online (AJOL)

    patterns to the given antibiotic are known. These are directly proportional to the antibiotic's percentage overall activity in the case of ATSR or its percentage overall resistance (POR) in the case of ATFR. Mathematically ATSR = C*POA and ATFR = C*POR. The proportionality constant “C” in the two formulae is presumed to.

  1. Final Environmental Assessment (EA) for Replacement of the Kennel Facility (Building 949) GHLN 11-6002 F. E. Warren Air Force Base, Wyoming

    Science.gov (United States)

    2012-01-01

    grass (Stipa comata), and fringed sagewort (Artemisia figida). Wet meadows on the Base are dominated by foxtail barley (Hordeum jubatum), Kentucky...bluegrass (Poa pratensis), tall wheatgrass (Elymus elongatus), baltic rush (Juncus balticus), tufted hairgrass (Deschampsia cespitosa), bluejoint grass ...columbianus), Canada goose (Branta canadensis), and wood duck (Aix sponsa). The birds-of-prey recorded on the Base include the turkey vulture

  2. Synopsis: the role of prescribed burning in regenerating Quercus macrocarpa and associated woody plants in stringer woodlands in the Black Hills, South Dakota

    Science.gov (United States)

    Carolyn Hull Sieg; Henry A. Wright

    1998-01-01

    Poor tree reproduction, sparse shrub cover, and increasing amounts of exotic species such as Kentucky bluegrass (Poa pratensis) are common problems in woody draws in the Northern Great Plains. Although the historic role of fire in maintaining woody draws is unclear, it is likely that these woodlands burned periodically, especially in dry years on hot...

  3. Fabrication of poly(o-anisidine) coated silica core–shell microspheres and their electrorheological response

    Science.gov (United States)

    Lee, Chul Joo; Choi, Hyoung Jin

    2017-11-01

    In this work, silica/poly(o-anisidine) (POA) core–shell structured microspheres were synthesized by coating the silica core surface with POA with a help of a chemical grafting agent, N-[(3-trimethoxylsilyl)-propyl] aniline. The synthesized silica microspheres were then applied as a polymer/inorganic composite particle-based electrorheological (ER) fluid. The morphology of the silica/POA microspheres was examined by using both transmission electron microscopy and scanning electron microscopy, while their thermal properties and chemical structure were checked by thermogravimetric analysis and Fourier-transform infrared spectroscopy, respectively. The ER properties of the silica/POA particle-based ER fluid were examined by using a Couette-type rotational rheometer equipped with a high-voltage power supplier and analyzed by the Bingham model and modified Mason number. In order to obtain additional information about the electrical polarization properties, the dielectric spectra were measured by an LCR meter and fitted by using the Cole–Cole equation. Furthermore, suspension stability of the ER fluid was tested using Turbiscan.

  4. Chernobyl Doses. Volume 1. Analysis of Forest Canopy Radiation Response from Multispectral Imagery and the Relationship to Doses

    Science.gov (United States)

    1994-09-01

    often dune vegetation, including Festuca ovina, F. rubra, Poa pratensis, Deschampsia caesrvitosa, Carex arenaria (sand sedge), and Trifolium arvense...revellum, S. acutifolium, Hypnum schreberi, and H. crista-castrensis. Such bogs also have Eriophorum vaginatum (sheathed cottongrass), Carex pauciflora...cattails), Carex vesicaria, C. gracilis, C. pseudocyperus, C. rostrata. Sedge bogs often include Carexfiliformis (large sedge), C. vesicaria, C

  5. Trinidad Reservoir Salvage Archaeology, 1972.

    Science.gov (United States)

    1974-09-30

    Symphori- carpos vaccinoides 140 Occurrence: Southern Rocky Mountains and Arizona ALPINE MEADOWS AND BARREN (AGROSTIS, CAREX , FESTUCA, POA Physiognomy...Usually short grasses and sedgesa, dense to very open with extensive barren areas; many forbs Dominants: Bentgrass (Argrostis spp.) Sedges ( Carex app...Spike trisetine (Trisetwn spicatum) Other Components: Achilica app., Antennaria app., Aquilegia app., Arenaria app., Castilleja app., Draba spp., Erigeron

  6. Portulaca oleracea Linn seed extract ameliorates hydrogen ...

    African Journals Online (AJOL)

    After 24 h of exposure, MTT and NRU assays were used to evaluate cell viability, while morphological changes were assessed using phase contrast inverted microscopy. The effect of POA on reduced glutathione (GSH) level, lipid peroxidation (LPO), and ROS generation induced by H2O2 was also studied. Results: The ...

  7. M-X Environmental Technical Report. Environmental Characteristics of Alternative Designated Deployment Areas, Native Vegetation.

    Science.gov (United States)

    1980-12-22

    penstemon Poa fendleriana Mutton grass P. sandbergii Sandberg bluegrass Sitanion hystrix Squi rreltail Sporobolus cryptandrus Sand dropseed Stia...A Challenge, Salt Lake City: Univ. Utah Press. Couch, James Fitton, 1937. ’The chemistry of stockpoisoning plants." 3. Chem. Educ . 14:16-30. Cronin

  8. A Cultural Resource Inventory of the Left Bank of Lake Oahe: Burleigh and Emmons Counties, North Dakota. Volume 1

    Science.gov (United States)

    1986-11-01

    tuberosus, other species o anthus ), field mint (Mentha arvensis), blue vervain (Verbena hastata) and dock (Rumex spp.) are normal ly present in this...Poa pratensis ) and quackgrass (Agrophyron repens) (Keammerer et al. 19757 or redtop (Agrostis stolonifera). Wet meadows also extend along tributary

  9. Environmental Assessment of Short-Term Construction Projects at the 150th Fighter Wing, New Mexico Air National Guard, Kirtland Air Force Base, New Mexico

    Science.gov (United States)

    2003-01-01

    creeping barberry (Berberis repens), and Kentucky bluegrass (Poa pratensis ). Wildlife associated with the ponderosa pine and conifer forests...Gray Catbird Duetella caro11nensis ruficrissa Sprague’s P1p1t Anthus sprague1i ~ican Redstart Set1\\’haga rutic11h tr1colora Abert’s Towhee P1pi o

  10. Master Environmental Plan for Fort Devens, Massachusetts

    Science.gov (United States)

    1992-04-01

    arbutus Geraniaceae Geranium maculatum Wild geranium Gramineae Panicum spp. Panic grass Poa annua Spear grass Pos pratensis Bluegrass Iridaceae Iris...delawarensis Ring-billed gull Vu Chlidonias niger Black tern Tr Alcedinidae Megaceryle alcyon Belted kingfisher N, SRc, Tc* Motacillidae Anthus spinoletta

  11. Neuroanatomical distribution of oxytocin receptor binding in the female rabbit forebrain: Variations across the reproductive cycle.

    Science.gov (United States)

    Jiménez, Angeles; Young, Larry J; Triana-Del Río, Rodrigo; LaPrairie, Jamie L; González-Mariscal, Gabriela

    2015-12-10

    Oxytocin receptors (OTR) have been characterized in the brains of several mammals, including rodents, carnivores, and primates. Their species-specific distribution in the brain has been associated with species differences in social organization, including mating strategy and parenting behavior. In several species, the density of OTR binding in specific brain regions varies according to reproductive condition, including ovarian cycle, pregnancy and lactation. Rabbits are induced ovulators, polygamous, and monoparental but their distribution and regulation of brain OTR has not been described. Here we used receptor autoradiography to quantitatively characterize OTR binding in the brains of estrous, ovariectomized, late pregnant, and lactating does. Intense binding occurred in the prefrontal cortex (PFC), preoptic area (POA), lateral septum (LS; dorsal and ventral), hippocampus, and medial amygdala. Variations among the experimental groups were seen only in PFC, POA, LS. Ovariectomy increased OTR density in PFC but had the opposite effect in POA. Lactating does had significantly reduced OTR density, relative to late pregnancy, in PFC and POA. Our results are consistent with a possible role of OT in modulating social and maternal behavior in rabbits since the brain regions sensitive to OT have been implicated in social interaction, learning and memory, olfactory processing and maternal behavior. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Mechanism of Cytochrome P450 17A1-Catalyzed Hydroxylase and Lyase Reactions

    DEFF Research Database (Denmark)

    Bonomo, Silvia; Jorgensen, Flemming Steen; Olsen, Lars

    2017-01-01

    Cytochrome P450 17A1 (CYP17A1) catalyzes C17 hydroxylation of pregnenolone and progesterone and the subsequent C17–C20 bond cleavage (lyase reaction) to form androgen precursors. Compound I (Cpd I) and peroxo anion (POA) are the heme-reactive species underlying the two reactions. We have...

  13. Suicide gene therapy using reducible poly (oligo-D-arginine) for the treatment of spinal cord tumors.

    Science.gov (United States)

    Won, Young-Wook; Kim, Kyung-Min; An, Sung Su; Lee, Minhyung; Ha, Yoon; Kim, Yong-Hee

    2011-12-01

    Suicide gene therapy based on a combination of herpes simplex virus-thymidine kinase (HSV-tk) and ganciclovir (GCV) has obstacles to achieving a success in clinical use for the treatment of cancer due to inadequate thymidine kinase (TK) expression. The primary concern for improving anticancer efficacy of the suicide gene therapy is to develop an appropriate carrier that highly expresses TK in vivo. Despite great advances in the development of non-viral vectors, none has been used in cancer suicide gene therapy, not even in experimental challenge. Reducible poly (oligo-D-arginine) (rPOA), one of the effective non-viral carriers working in vivo, was chosen to deliver HSV-tk to spinal cord tumors which are appropriate targets for suicide gene therapy. Since the system exerts toxicity only in dividing cells, cells in the central nervous system, which are non-proliferative, are not sensitive to the toxic metabolites. In the present study, we demonstrated that the locomotor function of the model rat was maintained through the tumor suppression resulting from the tumor-selective suicide activity by co-administration of rPOA/HSV-tk and GCV. Thus, rPOA plays a crucial role in suicide gene therapy for cancer, and an rPOA/HSV-tk and GCV system could help promote in vivo trials of suicide gene therapy. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Final Environmental Assessment for Construction and Operation of the Edgemeade Readiness Center and Tactical Unmanned Aerial System Storage and Maintenance Facility Idaho Army National Guard Elmore County, Idaho

    Science.gov (United States)

    2010-07-01

    Artemisia spp.), cheatgrass (Bromus tectorum) and other weeds. The Danskin Mountains, 8 miles northeast of the project site, dominate the view to the...perfoliatum), cheatgrass, crested wheatgrass, Sandberg bluegrass (Poa secunda), basin big sagebrush ( Artemisia tridentata), and rabbitbrush...summer and following winter flower and fruit along with the annual cohort of the following year. Biennials may have a much larger reproductive output

  15. Biological Survey, Buffalo River and Outer Harbor of Buffalo, New York. Volume II. Data Report.

    Science.gov (United States)

    1982-06-01

    Brome grass *Poa pratensis L. Kentucky bluegrass Melilatus alba Desr. White sweet clover Rumex crispus L. Sour dock Artemisia Absinthium Wormwood...Heliopsis helianthoides Oxe eye " Artemisia vulsaris L. Mugwort Artemisia ludoviciana Nutt. Wormwood Saponaria officinales L. Bouncing Bet Potentilla recta

  16. Patrimoine linguistique au Kenya : Genèse et évolution du Sheng

    African Journals Online (AJOL)

    Pof

    publicitaires en sheng dans tous les coins de Nairobi. Il s'agit de Coca-Cola, Safaricom, la banque Barclays, Kenya Commercial Bank, la banque Equity, la banque CFC, East. African Breweries, Keroche Breweries, Unilever, etc. (voir le tableau 3). Société. Contenu publicitaire. Traduction. Coca cola. Msosi poa na Coke.

  17. The distribution and spread of alien vascular plants on Prince Edward Island

    NARCIS (Netherlands)

    Ryan, P.G.; Smith, V.; Gremmen, N.J.M.

    2003-01-01

    Surveys of alien plants at subantarctic Prince Edward Island in 2001 show that the ranges of all three introduced species have increased since the last survey in 1998. Poa annua, the longest-established species, increased its range substantially after 1987, prior to which it was confined to a single

  18. Cardiac Usage of Reducible Poly(oligo-D-arginine As a Gene Carrier for Vascular Endothelial Growth Factor Expression.

    Directory of Open Access Journals (Sweden)

    Jongsu Woo

    Full Text Available Developments of non-viral carriers have headed toward reducing cytotoxicity, which results from the use of conventional gene carriers, and enhancing gene delivery efficiency. Cys-(d-R9-Cys repeated reducible poly(oligo-D-arginine (rPOA is one of the most efficient non-viral carriers for gene therapy; however, while its efficiency has been verified in the lung and brain, it is necessary to confirm its activity in each organ or tissue since there are differences of gene carrier susceptibility to among tissue types. We therefore tested the compatibility of rPOA in cardiac tissue by in vitro or in vivo experiments and confirmed its high transfection efficiency and low cytotoxicity. Moreover, substantial regenerative effects were observed following transfection with rPOA/pVEGF expression vector complexes (79% decreased infarct size compared to polyethyleneimine (PEI (34% decreased infarct size in a rat myocardial infarction (MI model. These findings suggest that rPOA efficiently enables DNA transfection in cardiac tissue and can be used as a useful non-viral therapeutic gene carrier for gene therapy in ischemic heart disease.

  19. Browse Title Index

    African Journals Online (AJOL)

    Items 9601 - 9650 of 11090 ... Vol 4, No 7 (2005):, Shelf stability of agidi produced from maize (Zea mays) and the effects of sodium benzoate treatment in combination with low temperature ... Vol 12, No 1 (2013), Silicon improves growth and antioxidative defense system in salt-stressed Kentucky bluegrass (Poa pratensis L.), ...

  20. Performance of low-input turfgrass species as affected by mowing and nitrogen fertilization in Minnesota

    Science.gov (United States)

    In Minnesota, most lawns and higher cut turfgrass areas consist primarily of species such as Kentucky bluegrass (Poa pratensis L.) and perennial ryegrass (Lolium perenne L.) that require significant management inputs such as frequent mowing and nitrogen fertility. Several studies have shown that oth...