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Se caracterizaron tres tipos de borde de bosque altoandino: borde de Chusquea scandens, paramizado y antiguo; este último denominado así por presentar un estado sucesional más avanzado. Se seleccionaron dos parches de bosque por cada tipo de borde, para analizar 13 criterios entre fisiográficos, microclimáticos, estructura y composición de la vegetación. Tres de los criterios (pendiente, forma y área del parche) son poco determinantes del tipo de hábitat de borde, los demás están estrechamente relacionados con las condiciones del microambiente y éste a su vez con la estructura y composición de la vegetación, confiriendo características particulares a cada hábitat de borde. El borde paramizado muestra la menor capacidad de autorregulación ambiental estando más expuesto a la fluctuación en estas variables, debido a su exposición directa a la acción del viento y a la pérdida de los estratos arbóreos más altos (entre 10 y 15 m), por lo que requiere la mayor intervención para su restauración. El borde de chusque es el más resguardado al actuar esta especie como una barrera protectora, que sin embargo debe ser controlada para promover la expansión del bosque como habita en el borde antiguo, el cual presenta una capacidad reguladora intermedia entre los otros dos.Characterization of High Andean forest edges and implications for their ecological restoration (Colombia). The growth of a forest patch through colonization of the adjacent matrix is mostly determined by the particular characteristics of the edge zone. Knowing how these characteristics are related to a specific edge type and how they influence the regeneration process, is important for High Andean forest edges restoration. This study aimed to characterize three types of High Andean forest edge in Cogua Forest Reserve (Colombia): 1) edge of Chusquea scandens, 2) "paramizado", and 3) old edge, characterized for being in a later successional state. Two forest patches were chosen for each edge type and 13 criteria were analyzed; these were of topographic order, micro-environmental order, vegetation structure and species composition. in each patch the vegetation was evaluated by means of two 60 m transects perpendicular to the edge and along the matrix-edgeinterior of the forest gradient. All woody plant species were identified and counted to determine their abundance. Environmental variables (air temperature, relative humidity, wind speed, and light radiation) were measured in one of the transects. Three of the 13 criteria were of little importance in shaping the type of edge habitat (slope, patch shape and area). The others were closely related with the micro-environmental conditions and in turn with the vegetation structure and composition; this relationship confers particular characteristics to each edge type. The microclimate and floristic edge limits coincided; edges extend between 10 and 20 m into the forest depending on the edge type. The paramizado edge has the smallest environmental self-regulation capacity and is more exposed to fluctuations of the studied variables, because of its greatest exposition to the wind action and loss of the tallest trees (between 10 and 15 m) which regulate the understorey microclimate. This low environmental buffer capacity prevents the establishing of mature forest species (for example, Schefflera sp. and Oreopanax bogotensis) although they are found in other areas within the same patch. All these results show that the paramizado edge needs the most intervention for its restoration. The Chusquea scandens edge forest is the most sheltered since this species acts as a protecting shield. However it still needs to be controlled to allow the adjacent matrix colonization by the forest species and natural regeneration, as it does in the old edge type forest, which moreover has an intermediate self-regulating capacity relative to the other two. The vegetation composition reveals that most of the edge species can also grow inside, beyond the forest edge. Rev. Biol. Trop. 56 (3): 1543-1556. Epub 2008 September 30.

El presente estudio se realizó en la Reserva Forestal Municipal de Cogua (Cundinamarca, Colombia), como parte del proyecto “Hacia un modelo de restauración del bosque”. Tiene como objetivos caracterizar el borde de avance del bosque, dominado por la especie Chusquea scandens y evaluar la regeneración de especies luego de disturbios experimentales a lo largo del borde de bosque. Con el primero se generó información preliminar del estado del borde de avance y del potencial que puede existir allí para la regeneración natural de la vegetación, el muestreo se realizó entre los meses de julio y octubre de 2003, en el cual se evaluaron algunas condiciones bióticas, abióticas y edáficas por medio del método línea intercepto a lo largo del gradiente pastizal-chuscal-bosque. El segundo estableció que tipo de disturbios son favorables para activar y potencializar la regeneración en los bordes de avance dominados por el chusque, los disturbios se basaron en reducir la competencia que hace el chusque por luz, así como también aumentar la disponibilidad de espacio para el establecimiento de otras especies. Para la caracterización del borde de avance se obtuvo que hacia el pastizal el chusque presenta una alta densidad que genera una zona de difícil acceso, lo cual puede funcionar como una barrera natural que reduce la influencia de especies de áreas abiertas en el interior del borde de avance, en donde se presentan pequeños claros donde el chuscal se reduce y se muestra una regeneración natural de especies. Además se estableció que a altas densidades del chusque se reducen las posibilidades de regeneración natural y la implantación de especies arbóreas, así como también, que la regeneración presentada hacia el interior del borde de avance está dominada por especies de borde y de bosque, siendo las herbáceas, enredaderas y arbustos las formas de crecimiento más importantes. Luego de los disturbios experimentales se obtuvo que las condiciones de sombra artificial sobre un terreno con remoción del suelo generan altas abundancias de especies, así como también la presencia de especies únicas. Se estableció además, que mantener la capa superficial del suelo es favorable para la regeneración debido a que se mantiene gran parte de las semillas viables acumuladas sobre el suelo.

The article presents a study on the early stages and ecological associations of Antirrhea adoptiva porphyrosticta, Lepidoptera:Nymphalidae:Morphinae, in eastern Ecuador. The Antirrhea larvae were collected and observed throughout the course of eight years. The study found out that Chusquea Kunth bamboo serves as the food of Antirrhea species. Moreover, the larvae of Antirrhea species are similar to other Antirrhea species and its caterpillars are parasitized by Ichneumonidae and braconidae.

The growth of a forest patch through colonization of the adjacent matrix is mostly determined by the particular characteristics of the edge zone. Knowing how these characteristics are related to a specific edge type and how they influence the regeneration process, is important for High Andean forest edges restoration. This study aimed to characterize three types of High Andean forest edge in Cogua Forest Reserve (Colombia): 1) edge of Chusquea scandens, 2) "paramizado", and 3) old edge, characterized for being in a later successional state. Two forest patches were chosen for each edge type and 13 criteria were analyzed; these were of topographic order, micro-environmental order, vegetation structure and species composition. In each patch the vegetation was evaluated by means of two 60 m transects perpendicular to the edge and along the matrix-edgeinterior of the forest gradient. All woody plant species were identified and counted to determine their abundance. Environmental variables (air temperature, relative humidity, wind speed, and light radiation) were measured in one of the transects. Three of the 13 criteria were of little importance in shaping the type of edge habitat (slope, patch shape and area). The others were closely related with the micro-environmental conditions and in turn with the vegetation structure and composition; this relationship confers particular characteristics to each edge type. The microclimate and floristic edge limits coincided; edges extend between 10 and 20 m into the forest depending on the edge type. The paramizado edge has the smallest environmental self-regulation capacity and is more exposed to fluctuations of the studied variables, because of its greatest exposition to the wind action and loss of the tallest trees (between 10 and 15 m) which regulate the understorey microclimate. This low environmental buffer capacity prevents the establishing of mature forest species (for example, Schefflera sp. and Oreopanax bogotensis) although they are found in other areas within the same patch. All these results show that the paramizado edge needs the most intervention for its restoration. The Chusquea scandens edge forest is the most sheltered since this species acts as a protecting shield. However it still needs to be controlled to allow the adjacent matrix colonization by the forest species and natural regeneration, as it does in the old edge type forest, which moreover has an intermediate self-regulating capacity relative to the other two. The vegetation composition reveals that most of the edge species can also grow inside, beyond the forest edge. [ABSTRACT FROM AUTHOR]