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Subject: SEQUIA ×

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Now showing 1 - 5 of 5
  • Artículo de revista
    Comportamiento frente a la sequía de plantas rebrotadas tras tala en bosque mediterráneo el caso de Quercus ilex
    Se estudio la conducta ecofisiológica en respuesta a la sequía de plantas de encina (Quercus ilex L.) intactas (controles) y plantas rebrotadas tras tala de la misma especie. El experimento se realizó a lo largo de un año en la Sierra de Collserola, Barcelona, España utilizando diversas de bosque con diferente disponibilidad de agua en el suelo
    Fleck, Isabel-Aranda Fratarolla, Xavier-Peña Rojas, Karen Angélica
    2009
  • Libro
    Influencia del clima sobre crecimiento de Roble (Nothofagus obliqua (Mirb.) Oerst.) y resiliencia de la especie frente a las sequías en el centro-sur de Chile
    Debido a la importancia de la especie roble y a que no existen estudios que hayan evaluado cómo el cambio climático puede afectar su crecimiento, los objetivos de este trabajo son los siguientes: Evaluar la relación entre el crecimiento radial (en ancho de anillos) y el clima en renovales de roble a lo largo de su distribución en la Cordillera de Los Andes. Evaluar la resiliencia del crecimiento de roble a las sequías ocurridas en décadas recientes y si las poblaciones creciendo en el norte de su distribución han sido afectadas por la megasequía. Evaluar si existe alguna tendencia en la productividad primaria de estos renovales durante las últimas dos décadas, a través del Índice de Vegetación de Diferencia Normalizada (NDVI) para todo el gradiente latitudinal en la Cordillera de los Andes.
    Urrutia-Jalabert, Rocío-Rojas Ponce, Yasna
    2020
  • Artículo de revista
    Relación temporal NDVI - Precipitación del bosque y pastizal natural de Santiago del Estero, Argentina = Temporary NDVI - Precipitation relation of natural forest and grassland in Santiago del Estero, Argentina
    En la provincia de Santiago del Estero, Argentina, fueron analizadas las relaciones y tendencias mensuales entre muestras del Índice de Vegetación de Diferencia Normalizada (NDVI) derivados del sensor Vegetation, del bosque nativo y pastizal natural, con datos de precipitaciones media mensual derivados de la base WorldClim
    Tiedemann, J. L.-Zerda, H. R.
    2008
  • Artículo de revista
    Climate response and drought resilience of Nothofagus obliqua secondary forests across a latitudinal gradient in south-central Chile
    The climate response and resilience of tree growth to drought events have been widely reported for forests from the Northern Hemisphere. However, studies are much scarcer in the extra-tropical forests of southern South America. Mediterranean and Temperate forests of Chile are suffering from a moderate warming and a sustained precipitation decrease, occurring on top of an unprecedented megadrought since 2010. This study evaluated tree-growth patterns, the climate response and drought resilience of nine secondary Nothofagus obliqua forests across a latitudinal gradient from Mediterranean to Temperate climate in the Andes of Chile (35.7° to 40.3° S). Moreover, to improve the understanding of the spatial variation in productivity patterns, this research assessed trends in the maximum Normalized Difference Vegetation Index (peak in the NDVI) across the gradient for 2001–2018. Tree-growth patterns were highly influenced by stand dynamics, with steep decreasing trends in most of the stands related to a gradual canopy closure. Productivity trends had a flat pattern north of 38oS, but positive trends south of this latitude, which were mostly attributed to stand development. Tree growth was positively related to precipitation in all the sites, with annual and summer rainfall being more important in the north (Mediterranean climate) and south (Temperate climate), respectively. Conversely, maximum temperature had a negative effect on growth in most of the studied forests. This implies that projected warmer and drier conditions may have a detrimental effect on N. obliqua growth during coming decades. The two northern stands, located at the species dry range edge, were among the most resilient to drought and have not been strongly affected by the current megadrought in the area. Overall climate conditions, however, do not define the tolerance of stands to droughts, likely because local environmental and forests conditions play a key role. Although droughts have not strongly impacted the growth of N. obliqua across its distribution so far, future studies should assess the effects of the current long-term megadrought on growth resilience, and physiological studies should address the impacts of droughts and heat waves on forest function beyond what growth can unveil.
    Urrutia-Jalabert, Rocío-Barichivich Henríquez, Jonathan Eligio-Rozas, V.-Lara Aguilar, Antonio-Rojas Ponce, Yasna-Bahamóndez V., Carlos-Rojas-Badilla, Moisés-Gipoulou-Zuñiga, T.-Cuq, Emilio
    2021
  • Artículo de revista
    The recruitment of the recalcitrant-seeded Cryptocarya alba (Mol.) Looser, established via direct seeding is mainly affected by the seed source and forest cover
    Natural regeneration of recalcitrant-seeded tree species is strongly limited in Mediterraneantype climate zones due to increasing droughts imposed by climate change. Direct seeding can be a low-cost alternative to seedling establishment, but there is still limited information for some species. This study aimed to assess the effects of the seed source and forest cover on the germination and survival of the endemic Cryptocarya alba Mol. established through direct seeding. Three habitat types differing in forest cover were identified within the natural park Reserva Natural Altos de Cantillana, Metropolitan Region, Chile. The forest cover corresponded to open (canopy density <25%), semidense (canopy density around 50%), and dense forest (canopy density >75%). All forest cover had C. alba as one of the dominant species. At each habitat type, 38 families from four seed sources (Cuesta La Dormida (CD), Antumapu (AN), Cantillana (CA, local seed source) and Cayumanque (CY)) were directly seeded. Germination (Germin) and survival (Surv) were evaluated weekly during one growing season. There were significant differences between seed sources in Germin and Surv, with means values varying from 7.8% to 37% for Germin and 0% to 20% for Surv. The local seed source CA had the highest values in both traits. A significant variation was also observed between families within seed sources only for Germin. The dense forest cover had the highest Germin (22%) and Surv (55%) results compared to the other forest cover types, which was partially associated with differences in soil moisture, temperature, and bulk density. Due to the most frequent droughts in these Mediterranean-type climate zones, the use of local seeds on dense forest cover is recommended for the direct seeding of the species in the initial recruitment.
    Magni, Carlos R.-Saavedra, Nicole-Espinoza, Sergio E.-Yañez, Marco A.-Quiroz Marchant, Iván-Faúndez, Angela F.-Grez M., Iván-Martínez, Eduardo E.
    Región Metropolitana de Santiago
    2022