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Actividad biológica del suelo en dos bosques de Nothofagus del centro sur de Chile Gayana Botánica
Rivas,Yessica; Godoy,Roberto; Valenzuela,Eduardo; Leiva,Javier; Oyarzún,Carlos; Alvear,Marysol.
Los bosques templados prístinos del sur de Chile tienen un bajo ingreso de nitrógeno (N) vía depositación atmosférica, por lo que la productividad del ecosistema depende principalmente del reciclaje interno de nutrientes, contenido en la materia orgánica del suelo (MOS). Se postula que existen diferencias en la actividad biológica del suelo entre un bosque secundario de Nothofagus obliqua de la Depresión Intermedia en Chile, influenciado por la actividad agrícola-ganadera y condiciones microclimáticas templadas favorables para la descomposición de la MOS, al comparar con un bosque prístino de Nothofagus betuloides de la Cordillera de los Andes, con microclima extremo. El presente estudio compara la tasa de mineralización de carbono (C-min), N (N-min) y las...
Tipo: Journal article Palavras-chave: Bosque templado; C- mineralización; N- mineralización; Dehidrogenasas; Fosfatasa ácida.
Ano: 2007 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-66432007000100008
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ATMOSPHERIC N DEPOSITION IN CENTRAL AND SOUTHERN CHILE: AN OVERVIEW Gayana Botánica
Godoy,Roberto; Paulino,Leandro; Oyarzún,Carlos; Boeckx,Pascal.
Temperate forests in Chile are not yet affected by elevated nitrogen (N) deposition. However, anthropogenic activities such as transport, industry and agriculture have been increasing in central and southern Chile. These activities can substantially alter the atmospheric N load and subsequently N deposition. Nitrogen deposition data for central and southern Chile are scares and scattered. In order to assess trends of N deposition a good knowledge of past and current N depositions is however essential. This study presents an overview of the existing N deposition data in Chile. In central Chile, dry deposition has been estimated at 0.8 kg NO3--N ha-1 yr-1 and 1.0 kg NH4+-N ha-1 yr-1, giving a total of 1.8 kg N ha-1 yr-1 and wet deposition was 0.4 kg NO3--N...
Tipo: Journal article Palavras-chave: Atmospheric deposition; Central and southern Chile; Mineral N; Organic N.
Ano: 2003 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-66432003000100008
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Dry deposition of nitrogen to passive samplers in grassland and forest canopies in the Central depression of southern Chile Gayana Botánica
Godoy,Roberto; Haneke,Jörgen; Staelens,Jeroen; Oyarzún,Carlos; Paulino,Leandro; Barrientos,Mónica.
The growth of intensive livestock farming in the central depression of southern Chile (40° S) during the last century has resulted in elevated emissions of inorganic nitrogen (N) compounds into the atmosphere, particularly of NH3. Consequently, atmospheric N has been deposited to lakes, vegetation, and soil. Much attention has been paid to wet N deposition in southern Chile, while almost nothing is known about dry N deposition in this region. Our aim is to use an exploratory approach with SAM (Standard Air Monitoring) filters to investigate the potential contribution of the dry N deposition to the total N deposition in the central depression of southern Chile. Furthermore, the relationship between micro-climatological patterns and dry deposition was...
Tipo: Journal article Palavras-chave: Atmospheric deposition; Nitrogen; Nothofagus obliqua forest; Pinus radiata plantation; Surrogate surface.
Ano: 2005 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-66432005000200006
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NEW PERSPECTIVES ON THE DETERMINATION OF PHOSPHATASE ACTIVITY IN ECTOMYCORRHIZAE OF NOTHOFAGUS OBLIQUA FORESTS IN SOUTHERN CHILE Gayana Botánica
Alvarez,Maricel; Härtel,Steffen; Godoy,Roberto; Heyser,Wolfgang.
We present a method to localise and quantify surface-bound phosphatase activity (SBPA) in mycorrhizal fungi and mycorrhizae of Nothofagus obliqua (Mirb.) Oerst., using image processed confocal fluorescent microscopy. ELF-97 is a hydrophilic substrate which turns into a strongly fluorescent precipitate upon activation by phosphomonoesterases. In fungal mycelium, this technique has recently been approved by comparison with a standard method (p-nitrophenyl-phosphate). The microscopic technique based on ELF-97 revealed that Paxillus involutus (Batsch: Fr.) Sing. and Austropaxillus boletinoides (Sing.) Brsky. & Jarosch provide different adaptive strategies to changing phosphate concentrations and different pH (3-7). We also analysed SBPA in four...
Tipo: Journal article Palavras-chave: Confocal microscopy; Ectomycorrhizae of Nothofagus obliqua; ELF-97; Phosphatase activity; Quantitative fluorescence microscopy.
Ano: 2003 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-66432003000100007
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NITROGEN FLUXES IN A NOTHOFAGUS OBLIQUA FOREST AND A PINUS RADIATA PLANTATION IN THE CENTRAL VALLEY OF SOUTHERN CHILE Gayana Botánica
Oyarzún,Carlos; Godoy,Roberto; Staelens,Jeroen; Aracena,Claudia; Proschle,Juan.
Forest structure and tree species can have a significant impact on total atmospheric nitrogen (N) deposition; for example, deciduous forests have higher N requirements than coniferous forests. However, knowledge about the effect of the conversion of native Chilean vegetation cover by exotic plantations on N cycling is scarce. The aim of this study was to determine the effect of the replacement of a Nothofagus obliqua native forest by a Pinus radiata plantation in southern Chile on the chemistry of throughfall, stemflow, soil water infiltration and percolation. Pinus radiata stemflow was more acidic (pH 4.7) than precipitation (pH 5.2) and throughfall (pH 5.6), while in the Nothofagus forest stemflow and throughfall pH were 6.3 and 6.1, respectively. In the...
Tipo: Journal article Palavras-chave: Ammonium; Infiltration; Nitrate; Soil percolation; Throughfall.
Ano: 2005 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-66432005000200004
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NITROGEN FLUXES IN THROUGHFALL AND LITTERFALL IN TWO NOTHOFAGUS FORESTS IN SOUTHERN CHILE Gayana Botánica
Staelens,Jeroen; Godoy,Roberto; Oyarzún,Carlos; Thibo,Karen; Verheyen,Kris.
Nitrogen return by leaf litterfall was compared with atmospheric nitrogen deposition for two deciduous Nothofagus stands in southern Chile, located in areas with contrasting land use. The litterfall return of nitrogen in a Nothofagus alpina (Poepp. et Endl.) Oerst. stand at San Pablo de Tregua, in the Cordillera de los Andes, was similar to the litterfall return in a Nothofagus obliqua (Mirb.) Oerst. stand at Paillaco, in the Central Depression. In contrast, the net throughfall and stemflow deposition differed significantly between the two stands. At San Pablo de Tregua, the annual bulk deposition of NH4+ and NO3- was significantly higher than the throughfall and stemflow deposition reaching the forest floor. This demonstrates an uptake of inorganic...
Tipo: Journal article Palavras-chave: Ammonium; Atmospheric deposition; Canopy interactions; Nitrate; Nutrient cycling; Amonio; Ciclos de nutrientes; Depositación atmosférica; Interacciones del dosel; Nitrato.
Ano: 2005 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-66432005000200002
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Physiological-enzymatic characteristics and inoculation of mycelial strains of Descolea antarctica Sing. in Nothofagus seedlings Electron. J. Biotechnol.
Valenzuela,Eduardo; Hipp,Joseline; Alonso,Claudia; Godoy,Roberto; Alberdi,Miren; Alvarez,Maricel; Saavedra,Isabel.
At present, reforestation has focused on native forests with anthropogenic intervention and eroded soils. There is interest in producing Nothofagus seedlings which can overcome adverse conditions encountered on reforestation sites. It is necessary to find new fungi that can be utilized as mycorrhizal inoculants and that enable the seedlings to increase their tolerance to adverse conditions. Two ectomycorrhizal strains of the fungus Descolea antarctica (D1 and D2) were cultured at different temperatures, pH levels and the activities of amylases, cellulases, and phosphatases were determined. In greenhouse and nursery trials, the growth responses of inoculated Nothofagus obliqua seedlings were evaluated. D1 and D2 exhibited the highest growth rates at 23ºC....
Tipo: Journal article Palavras-chave: Cellulose; Ectomycorrhizal fungi; Nothofagus; PH; Phosphatase; Temperature.
Ano: 2008 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000200012
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POSSIBILITIES FOR ECOHYDROLOGICAL MONITORING IN NATURAL AND MANAGED ECOSYSTEMS IN SOUTHERN CHILE Gayana Botánica
Peters,Jan; Wieme,Vanessa; Boeckx,Pascal; Samson,Roeland; Godoy,Roberto; Oyarzún,Carlos; Verhoest,Niko.
Ecohydrology investigates how hydrological processes affect plant growth and vice versa. As these mutual interactions are important in many ecosystems, ecohydrology has wide applicability. An important aspect of ecohydrological research is the assessment and prediction of the occurrence of plant species or vegetation types in relation to hydrological or hydrogeochemical habitat conditions. Several models have been developed (e.g. DEMNAT, ICHORS, ITORS, ITORS-VL). All of these models are data driven. Consequently a monitoring network has to be installed, possibly in addition to existing databases. These networks are ecosystem specific but the most widely monitored variables are: water table depth, electric conductivity of groundwater, soil moisture content...
Tipo: Journal article Palavras-chave: Ecohydrology; Modelling; Vegetation; Hydrology; Decision support systems.
Ano: 2005 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-66432005000200007
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Successional patterns along soil development gradients formed by glacier retreat in the Maritime Antarctic, King George Island RChHN
Boy,Jens; Godoy,Roberto; Shibistova,Olga; Boy,Diana; McCulloch,Robert; la Fuente,Alberto Andrino de; Morales,Mauricio Aguirre; Mikutta,Robert; Guggenberger,Georg.
BACKGROUND: Maritime Antarctica is severely affected by climate change and accelerating glacier retreat forming temporal gradients of soil development. Successional patterns of soil development and plant succession in the region are largely unknown, as are the feedback mechanisms between both processes. Here we identify three temporal gradients representing horizontal and vertical glacier retreat, as well as formation of raised beaches due to isostatic uplift, and describe soil formation and plant succession along them. Our hypotheses are (i) plants in Antarctica are able to modulate the two base parameters in soil development, organic C content and pH, along the temporal gradients, leading to an increase in organic carbon and soil acidity at relatively...
Tipo: Journal article Palavras-chave: Temporal gradients; Chronosequences; Soil succession; Soil organic carbon; Ornithic; Mycorrhiza; Maritime Antarctica; King George Island.
Ano: 2016 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2016000100007
Registros recuperados: 9
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