Structural and functional changes in Nothofagus pumilio forests along an altitudinal gradient in Tierra del Fuego, Argentina

2000 ◽  
Vol 11 (2) ◽  
pp. 179-188 ◽  
Author(s):  
Marcelo D. Barrera ◽  
Jorge L. Frangi ◽  
Laura L. Richter ◽  
Marcelo H. Perdomo ◽  
Luis B. Pinedo
Keyword(s):  
Altitudinal Gradient ◽  
Tierra Del Fuego ◽  
Nothofagus Pumilio ◽  
Functional Changes

Nutrient cycling in Nothofagus pumilio forests along an altitudinal gradient in Tierra del Fuego, Argentina

2005 ◽  
Vol 217 (1) ◽  
pp. 80-94 ◽  
Author(s):  
Jorge L. Frangi ◽  
Marcelo D. Barrera ◽  
Laura L. Richter ◽  
Ariel E. Lugo
Keyword(s):  
Nutrient Cycling ◽  
Altitudinal Gradient ◽  
Tierra Del Fuego ◽  
Nothofagus Pumilio

scholarly journals Litterfall and leaf decomposition in Nothofagus pumilio forests along an altitudinal gradient in Tierra del Fuego, Argentina

2014 ◽  
Vol 60 (No. 12) ◽  
pp. 500-510 ◽  
Author(s):  
A. Moretto ◽  
G.J. Martínez Pastur
Keyword(s):  
Soil Properties ◽  
Altitudinal Gradient ◽  
Reproductive Organ ◽  
Tierra Del Fuego ◽  
Litter Production ◽  
Nothofagus Pumilio ◽  
Decomposition Rates ◽  
P Content ◽  
Decomposition Dynamics ◽  
Microclimate Conditions

To achieve a fuller understanding of forest ecosystem functioning, it is necessary to know decomposition dynamics. The objective of this study was to quantify litter production, decomposition and mineralization in Nothofagus pumilio forests, in Tierra del Fuego, Argentina, along an altitudinal gradient during a two-year period and relate them to microclimate conditions and soil properties. We did the research along an altitudinal sequence at 210, 330, 460 and 590 m a.s.l., where climate, soil properties and forest structure were characterized. Litterfall decreased with altitude, and it was highly related with leaf and reproductive organ production. Decomposition decreased with altitude, being associated with microclimate and soil properties rather than with other measured variables, such as leaf chemistry. Values of decomposition constant (k) were influenced by altitude and varied between seasons and years within a given altitude. Nitrogen content increased with altitude in the two-year period, while P content decreased. Decomposition rates allowed us to separate the forest stands according to altitudinal gradients, and their intrinsic abiotic characteristics, which could increase the understanding of the nutrient flux and dynamics in these austral forest ecosystems.  

Four Centuries of Summer Temperature Changes in Tierra Del Fuego: Atmospheric Drivers and Tree-Ring Reconstruction From the Southernmost Forests of the World

2021 ◽  
Author(s):  
Vladimir Matskovsky ◽  
Fidel A. Roig ◽  
Mauricio Fuentes ◽  
Irina Korneva ◽  
Diego Araneo ◽  
...  
Keyword(s):  
Tree Ring ◽  
Ring Width ◽  
Temperature Reconstruction ◽  
Summer Temperature ◽  
Temperature Variability ◽  
Tierra Del Fuego ◽  
Climate Modelling ◽  
Least Squares Regression ◽  
Nothofagus Pumilio ◽  
The World

Abstract Proxy climate records, such as those derived from tree rings, are necessary to extend relatively short instrumental meteorological observations into the past. Tierra del Fuego is the most austral territory with forests in the world, situated close to the Antarctic Peninsula, which makes this region especially interesting for paleoclimatic research. However, high-quality, high-resolution summer temperature reconstruction are lacking in the region. In this study we used 63 tree-ring width chronologies of Nothofagus pumilio and Nothofagus betuloides and partial least squares regression (PLSR) to produce annually resolved December-to-February temperature reconstruction since AD 1600 which explains up to 65% of instrumental temperature variability. We also found that observed summer temperature variability in Tierra del Fuego is primarily driven by the fluctuations of atmospheric pressure systems both in the South Atlantic and South Pacific, while it is insignificantly correlated to major hemispheric modes: ENSO and SAM. This fact makes our reconstruction important for climate modelling experiments, as it represents specific regional variability. Our reconstruction can be used for direct comparison with model outputs to better understand model limitations or to tune a model or contribute to larger scale reconstructions based on paleoclimatic data assimilation. Moreover, we showed that PLSR has improved performance over principal component regression (PCR) in the case of multiple tree-ring predictors. According to these results, PLSR may be a preferable method over PCR for the use in automated tree-ring based reconstruction approaches, akin widely used point-by-point regression.

scholarly journals Inland water microcrustacean assemblages in an altitudinal gradient in Aysen region (46° S, Patagonia Chile)

2014 ◽  
Vol 74 (1) ◽  
pp. 8-15 ◽  
Author(s):  
Patricio De los Ríos-Escalante ◽  
Esteban Quinán ◽  
Patricio Acevedo
Keyword(s):  
National Park ◽  
Altitudinal Gradient ◽  
Null Model ◽  
Tierra Del Fuego ◽  
Species Number ◽  
Regional Studies ◽  
Inland Water ◽  
Chilean Patagonia ◽  
Water Ecosystems ◽  
Torres Del Paine

The Chilean Patagonia has numerous kinds of inland water ecosystems such as lakes, ponds, wetlands and rivers that have been poorly studied due to access difficulties. This study was carried out in Aysen region, in southern Chile, and it included different kinds of water bodies such as rivers, streams, ponds, lagoons and lakes distributed along an altitudinal gradient at 46° S. It was found a low species number, essentially cladocerans, copepods and amphipods. A null model was applied in order to determine the existence of regulator factors of species associations, and the results revealed that they are not random. The patterns would be influenced by geographical and limnological characteristics of the studied sites. Our results would agree with regional studies on habitat heterogeneity such as in Torres del Paine National Park and other zones in Tierra del Fuego island.

scholarly journals HISTORIA DEL BOSQUE EN EL CENTRO DE TIERRA DEL FUEGO, ARGENTINA

2019 ◽  
Vol 2 (3) ◽  
pp. 25-36
Author(s):  
Lidia S. Burry ◽  
Matilde E. Trivi de Mandri
Keyword(s):  
Tierra Del Fuego ◽  
Nothofagus Pumilio

Nothofagus pumilio es la especie forestal nativa de mayor importancia en Tierra del Fuego ocupa un área de 214,000 ha, y es la principal fuente de madera. En este trabajo se aportan elementos para la reconstrucción de la historia del bosque de Nothofagus pumilio en el centro de la Isla Grande de Tierra del Fuego, extremo austral del continente americano. La reconstrucción se realizó mediante el análisis polínico de tres segmentos de una columna de sedimentos, proveniente de una turbera de Sphagnum. Los granos de polen se extrajeron con técnicas físicas y químicas; se determinaron, contaron y los datos porcentuales se trataron estadísticamente mediante un análisis de ordenación, para lo cual se usó el análisis de correspondencia (CA programme). Los cambios del contenido polínico a lo largo del perfil muestran variaciones de los parámetros ambientales durante el Holoceno, en relación con el cambio de estepa a bosque. Se demuestra que en el centro de la Isla entre ca 6,800 y 7,775±205 años AP hubo una estepa de gramíneas, que se transformó en un bosque abierto entre 2,340±35 y 2,755±45 años AP, y a partir de 1,725±35 años AP se desarrolló el bosque cerrado, presente en la actualidad. Se supone que estas variaciones se relacionan con el aumento en la precipitación. Las asincronías en el establecimiento del bosque en otros sitios de Tierra del Fuego se deben al gradiente de humedad de los vientos del sureste.

scholarly journals El bosque como fuente de combustible: análisis antracológico de los sitios de la faja central de la Isla Grande de Tierra del Fuego

2020 ◽  
pp. 335-350
Author(s):  
Anna Franch Bach ◽  
M. Estela Mansur ◽  
Vanessa Parmigiani ◽  
Hernán H. De Angelis ◽  
M. Celina Alvarez Soncini ◽  
...  
Keyword(s):  
Tierra Del Fuego ◽  
Nothofagus Pumilio ◽  
Los Grupos

El objetivo de este trabajo es presentar el análisis antracológico de dos sitios de la faja central de la Isla Grande de Tierra del Fuego (Cabo San Pablo 2017 y Kami 7) y discutir la utilización de recursos leñosos por parte de los grupos que habitaron el área durante el Holoceno tardío. Se aplicó una metodología de análisis antracológico estándar, que incluyó la identificación taxonómica, la evaluación de alteraciones en la estructura de los carbones y estimación del calibre original de los leños utilizados. Los resultados demuestran un énfasis en el uso combustible de taxa de la clase fitosociológica Nothofagetea pumilionis-antarcticae, siendo Nothofagus pumilio y N. antartica/betuloides los más abundantes. Se registra una preponderancia de carbones de grandes calibres, de madera colectada en buen estado y alteraciones que reflejan eventos de altas temperaturas de fogón. De los resultados se deduce un aprovechamiento intenso y variado de los bosques cercanos a los sitios.

Timber production of Nothofagus pumilio forests by a shelterwood system in Tierra del Fuego (Argentina)

2000 ◽  
Vol 134 (1-3) ◽  
pp. 153-162 ◽  
Author(s):  
G Martı́nez Pastur ◽  
J.M Cellini ◽  
P.L Peri ◽  
R.F Vukasovic ◽  
M.C Fernández
Keyword(s):  
Tierra Del Fuego ◽  
Timber Production ◽  
Nothofagus Pumilio

scholarly journals Variable retention harvesting influences belowground plant-fungal interactions of Nothofagus pumilio seedlings in forests of southern Patagonia

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5008 ◽  
Author(s):  
Rebecca E. Hewitt ◽  
Donald Lee Taylor ◽  
Teresa N. Hollingsworth ◽  
Christopher B. Anderson ◽  
Guillermo Martínez Pastur
Keyword(s):  
Soil Moisture ◽  
Community Composition ◽  
Conservation Status ◽  
Tierra Del Fuego ◽  
Primary Forest ◽  
Nothofagus Pumilio ◽  
Variable Retention ◽  
Seedling Biomass ◽  
Rdna Sequencing ◽  
Southern Patagonia

Background The post-harvest recovery and sustained productivity of Nothofagus pumilio forests in Tierra del Fuego may be affected by the abundance and composition of ectomycorrhizal fungi (EMF). Timber harvesting alters EMF community structure in many managed forests, but the impacts of harvesting can vary with the management strategy. The implementation of variable retention (VR) management can maintain, increase, or decrease the diversity of many species, but the effects of VR on EMF in the forests of southern Patagonia have not been studied, nor has the role of EMF in the regeneration process of these forests. Methods We evaluated the effects of VR management on the EMF community associated with N. pumilio seedlings. We quantified the abundance, composition, and diversity of EMF across aggregate (AR) and dispersed (DR) retention sites within VR managed areas, and compared them to primary forest (PF) unmanaged stands. EMF assemblage and taxonomic identities were determined by ITS-rDNA sequencing of individual root tips sampled from 280 seedlings across three landscape replicates. To better understand seedling performance, we tested the relationships between EMF colonization, EMF taxonomic composition, seedling biomass, and VR treatment. Results The majority of EMF taxa were Basidiomycota belonging to the families Cortinariaceae (n = 29), Inocybaceae (n = 16), and Thelephoraceae (n = 8), which was in agreement with other studies of EMF diversity in Nothofagus forests. EMF richness and colonization was reduced in DR compared to AR and PF. Furthermore, EMF community composition was similar between AR and PF, but differed from the composition in DR. EMF community composition was correlated with seedling biomass and soil moisture. The presence of Peziza depressa was associated with higher seedling biomass and greater soil moisture, while Inocybe fibrillosibrunnea and Cortinarius amoenus were associated with reduced seedling biomass and lower soil moisture. Seedling biomass was more strongly related to retention type than EMF colonization, richness, or composition. Discussion Our results demonstrate reduced EMF attributes and altered composition in VR treatments relative to PF stands, with stronger impacts in DR compared to AR. This suggests that VR has the potential to improve the conservation status of managed stands by supporting native EMF in AR. Our results also demonstrate the complex linkages between retention treatments, fungal community composition, and tree growth at individual and stand scales.

scholarly journals Bosques mixtos de Nothofagus pumilio y N. betuloides: ¿son estables?

2019 ◽  
Author(s):  
◽  
Mónica Toro Manríquez
Keyword(s):  
El Paso ◽  
Tierra Del Fuego ◽  
Nothofagus Pumilio ◽  
Cordillera De Los Andes

Introducción: La variación en la fenología reproductiva de las especies es un mecanismo importante para mantener la coexistencia de las mismas en los bosques mixtos. En estos, el impacto de los factores limitantes (bióticos y abióticos) en el éxito reproductivo podría estar influenciando sobre las proporciones de las especies que los conforman, variando entre una condición estable y una transición hacia tipos forestales monoespecíficos. Este estudio permite una aproximación basada en las primeras etapas del ciclo de regeneración natural de los bosques mixtos de Nothofagus deciduos-siempreverdes en Tierra del Fuego, evaluando las etapas de floración, pre-dispersión y post-dispersión de nueces, instalación y supervivencia de plantas de regeneración, y de los factores de pérdida en cada etapa, para tres tipos de bosques mixtos: con dominancia de la especie caducifolia Nothofagus pumilio, con dominancia de la especie siempreverde Nothofagus betuloides y con una proporción de aproximadamente 1:1 de ambas especies, comparando dos localizaciones geográficas (costa y montaña), durante tres ciclos de regeneración completos (C1: 2013- 2014, C2: 2014-2015, C3: 2015-2016) y dos años posteriores a la instalación de las tres cohortes generadas (hasta enero 2018). Objetivo: Determinar si los bosques mixtos de Nothofagus de Tierra del Fuego, considerando tres condiciones diferentes de dominancia de N. pumilio y N. betuloides y dos localizaciones geográficas características, se encuentran en un estado estable o representan transiciones hacia tipos forestales con dominancia de una especie, a través del análisis de las primeras etapas de su ciclo de regeneración natural (floración, pre- y post dispersión de nueces, instalación de plántulas y supervivencia de plantas); y de la probabilidad de transición desde la flor hasta la plántula. Área de estudio: Bosques coetáneos de Nothofagus (>250 años) sin impacto de cosecha, al sur-oeste de Tierra del Fuego (Argentina). Los rodales de costa se ubicaron cercanos al Canal del Beagle, dentro del Parque Nacional Tierra del Fuego, mientras que los rodales de montaña, se ubicaron hacia el interior de la Isla, en el Paso Garibaldi (Cordillera de Los Andes fueguinos).

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