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Coffee agroforestry systems (CAFS) are of productive importance in the state of Oaxaca. In the last 20 years they have been affected by various factors that promote land-use change and thereby increase greenhouse gases. In order to analyze the structure and accumulation of aerial biomass in a CAFS and fit allometric biomass equations for Coffea arabica L., an experiment was established under a completely randomized design, under three levels of crown cover in 400 m2 experimental units in which dasometric measurements of all the trees were recorded; the data were subjected to an analysis of variance and Duncan's multiple range test (p ≤ 0.05). By means of regression, the aerial biomass equations of the coffee trees were selected. The CAFS structure is irregular; in total, 14 species were identified, with the most frequently occurring being the species Inga edulis Mart (749 trees ha-1) and Liquidambar styraciua L. (493 trees ha-1). The highest biomass accumulation was found in CAFS with mean cover level for shade trees and aerial total of 43 and 86% with 78.4 ± 29.4 and 87.02 ± 33.3 t ha-1. The biomass on the ground did not show significant differences among the cover levels evaluated. The aerial biomass compartments for C. arabica are estimated with fit coefficients between 0.71 and 0.89, where the basal diameter and height of the coffee trees are independent variables., Los sistemas agroforestales de café (SAFC) son de importancia productiva en el estado de Oaxaca. En los últimos 20 años han sido afectados por diversos factores que promueven el cambio de uso de suelo e incrementan los gases de efecto invernadero. Con el objetivo de analizar la estructura y acumulación de biomasa aérea en un SAFC y ajustar ecuaciones alométricas de biomasa para Coffea arabica L, se estableció un experimento bajo un diseño completamente al azar, con tres niveles de cobertura de copa en unidades experimentales de 400 m2, en las que se registraron medidas dasométricas de todos los árboles, los datos se sometieron a un análisis de varianza y pruebas de medias de Duncan (p ≤ 0.05); por medio de regresión se seleccionaron las ecuaciones de biomasa aérea de los cafetos. La estructura del SAFC es irregular, se identificaron 14 especies presentando mayor frecuencia las especies Inga edulis Mart (749 árboles ha-1) y Liquidambar styraciflua L. (493 árboles ha-1). La mayor acumulación de biomasa se encontró en SAFC con nivel medio de cobertura para árboles sombra y total aéreo de 43 y 86% con 78.4 ± 29.4 y 87.02 ± 33.3 t ha-1. La biomasa en el piso no mostró diferencias significativas entre los niveles de cobertura evaluados. Los compartimentos de biomasa aérea para C. arabica se estiman con coeficientes de ajuste entre 0.71 y 0.89, donde el diámetro basai y altura de los cafetos son variables independientes.

Aim of the study: To analyse the effectiveness of thinning on tree growth, forest structure and microclimatic variables along seven years after cuttings in a secondary Nothofagus antarctica forest in Southern Patagonia.Area of study: Five hectares of homogeneous stand of secondary forests (54º15’46” SL, 66º59’41” WL) in Tierra del Fuego, Argentina.Material and methods: One control and two thinning levels were established, and forest structure, growth, crown dynamic and microclimate variables in long-term permanent plots were evaluated. Main comparisons were made using multiple ANOVAs.Main results: Intensive thinning in secondary forests allowed to increase tree individual growth rates by doubling the radiation levels at the understory level that enhances the silvopastoral management. These forests showed a desirable resilience to the forest interventions and natural disturbances (e.g. heavy defoliator attack), with a rapid reaction in the canopy cover growth.Research highlights: Monitoring of thinning for silvopastoral management must include easy and cheap measuring variables, e.g. diameter growth as a proxy for timber production objectives and hemispherical photos (crown cover and radiation) as a proxy for pasture production. Long-term monitoring allowed to identify reliable indicators that assist new sustainable management alternatives.

Aim of the study: To analyse the effectiveness of thinning on tree growth, forest structure and microclimatic variables along seven years after cuttings in a secondary Nothofagus antarctica forest in Southern Patagonia.Area of study: Five hectares of homogeneous stand of secondary forests (54º15’46” SL, 66º59’41” WL) in Tierra del Fuego, Argentina.Material and methods: One control and two thinning levels were established, and forest structure, growth, crown dynamic and microclimate variables in long-term permanent plots were evaluated. Main comparisons were made using multiple ANOVAs.Main results: Intensive thinning in secondary forests allowed to increase tree individual growth rates by doubling the radiation levels at the understory level that enhances the silvopastoral management. These forests showed a desirable resilience to the forest interventions and natural disturbances (e.g. heavy defoliator attack), with a rapid reaction in the canopy cover growth.Research highlights: Monitoring of thinning for silvopastoral management must include easy and cheap measuring variables, e.g. diameter growth as a proxy for timber production objectives and hemispherical photos (crown cover and radiation) as a proxy for pasture production. Long-term monitoring allowed to identify reliable indicators that assist new sustainable management alternatives.

Coffee agroforestry systems (CAFS) are of productive importance in the state of Oaxaca. In the last 20 years they have been affected by various factors that promote land-use change and thereby increase greenhouse gases. In order to analyze the structure and accumulation of aerial biomass in a CAFS and fit allometric biomass equations for Coffea arabica L., an experiment was established under a completely randomized design, under three levels of crown cover in 400 m2 experimental units in which dasometric measurements of all the trees were recorded; the data were subjected to an analysis of variance and Duncan's multiple range test (p ≤ 0.05). By means of regression, the aerial biomass equations of the coffee trees were selected. The CAFS structure is irregular; in total, 14 species were identified, with the most frequently occurring being the species Inga edulis Mart (749 trees ha-1) and Liquidambar styraciua L. (493 trees ha-1). The highest biomass accumulation was found in CAFS with mean cover level for shade trees and aerial total of 43 and 86% with 78.4 ± 29.4 and 87.02 ± 33.3 t ha-1. The biomass on the ground did not show significant differences among the cover levels evaluated. The aerial biomass compartments for C. arabica are estimated with fit coefficients between 0.71 and 0.89, where the basal diameter and height of the coffee trees are independent variables., Los sistemas agroforestales de café (SAFC) son de importancia productiva en el estado de Oaxaca. En los últimos 20 años han sido afectados por diversos factores que promueven el cambio de uso de suelo e incrementan los gases de efecto invernadero. Con el objetivo de analizar la estructura y acumulación de biomasa aérea en un SAFC y ajustar ecuaciones alométricas de biomasa para Coffea arabica L, se estableció un experimento bajo un diseño completamente al azar, con tres niveles de cobertura de copa en unidades experimentales de 400 m2, en las que se registraron medidas dasométricas de todos los árboles, los datos se sometieron a un análisis de varianza y pruebas de medias de Duncan (p ≤ 0.05); por medio de regresión se seleccionaron las ecuaciones de biomasa aérea de los cafetos. La estructura del SAFC es irregular, se identificaron 14 especies presentando mayor frecuencia las especies Inga edulis Mart (749 árboles ha-1) y Liquidambar styraciflua L. (493 árboles ha-1). La mayor acumulación de biomasa se encontró en SAFC con nivel medio de cobertura para árboles sombra y total aéreo de 43 y 86% con 78.4 ± 29.4 y 87.02 ± 33.3 t ha-1. La biomasa en el piso no mostró diferencias significativas entre los niveles de cobertura evaluados. Los compartimentos de biomasa aérea para C. arabica se estiman con coeficientes de ajuste entre 0.71 y 0.89, donde el diámetro basai y altura de los cafetos son variables independientes.

Aim of study: Harvesting proposals (e.g. variable retention) for Nothofagus pumilio forests are based on canopy opening, to increase recruitment and enhance seedling growth, by modifying light and soil moisture. Seed production and seedling recruitment will define the success of harvesting, where remnant forest structure are the main influence factors, as well as biotic and abiotic factors. The objective was to analyse seed production, seedling recruitment and recruitment efficiency in primary and harvested forests through variable retention along the first 10 years after harvesting, as well as the influence of regional climate. Area of study: The study were conducted in a pure Nothofagus pumilio forest located in central Tierra del Fuego (54°18’ S, 67°49’ W), where harvested stands with variable retention and unmanaged forests were sampled in long-term permanent plots. Material and methods: Data of forest regeneration plots were used (n = 72) (2007 a 2014), and forest structure and seed production (2006 a 2013) were also measured. Regional climate was characterised for these years from satellite images (Sea Surface Temperature) and climate re-analysis models (rainfall and temperature of land surface). Main results: Harvesting modified forest structure; however, aggregated retention maintained some characteristics of the primary unmanaged forests. These changes influenced seed production and recruitment. Seed production and recruitment were related to crown cover and the amount of seed production; however, recruitment efficiency was not affected by harvesting. The studied variables significantly changed along the years after harvesting. Seed production and recruitment were also related to regional climate factors, where it was possible to explain their variations through temperature (e.g. summer temperature) and rainfall (e.g. winter rainfall) for the different retention types in harvested forests and the primary forests. Research highlights: Variable retention harv