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El objetivo fue evaluar los requerimientos de germinación de Phacelia secunda J.F. Gmel. y Eryngium paniculatum Cav. y Dombey ex F. Delaroche, herbáceas perennes colonizadoras de ambientes degradados del noroeste patagónico argentino y de interés para la restauración ecológica. Se evaluó el porcentaje, tiempo medio e inicio de germinación en un control (C) y dos tratamientos pre-germinativos: escarificación mecánica con bisturí (EM) y estratificación húmeda fría durante 45 días (EHF). En P. secunda, el porcentaje de germinación en el tratamiento EHF (2%) fue menor que en el C (24%) y el tratamiento EM (16%). En E. paniculatum se encontraron diferencias entre el C (94%) y el tratamiento EHF (82%), pero no entre el C y EM (91%). El tratamiento EHF aceleró el inicio de la geminación en ambas especies. Las semillas de P. secunda mostraron baja capacidad de germinación siendo necesario evaluar nuevos tratamientos. Eryngium paniculatum mostró alta capacidad germinativa aún en el control, lo que evidencia que no requiere tratamientos pregerminativos específicos. The aim was to evaluate the seed germination requirements of Phacelia secunda J.F. Gmel. and Eryngium paniculatum Cav. y Dombey ex F. Delaroche, perennial herbaceous colonizers of degraded environments of northwest Argentinian Patagonia and of interest for ecological restoration. The germination percentage, mean germination time and time until initiation of germination of a control (C) and two pre-germination treatments: Mechanical scarification with a scalpel (EM) and 45 days cold moist stratification (EHF) were evaluated. In P. secunda, the germination percentage in EHF treatment (2%) was lower than in C (24%) and EM (16%) treatment. In E. paniculatum, differences between C (94%) and EHF (82%) were found, but not between C and EM (91%). EHF treatment accelerated the germination initiation in both species. Seeds of P. secunda showed low germination capacity being necessary to evaluate new treatments. Eryngium paniculatum showed high germination capacity in the control. Thus this species does not require specific pre-germination treatments. Fil: Chichizola, Giselle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Rovere, Adriana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Gonzalez, Sofia Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina

The introduction of alien species represents one of the greatest threats to biodiversity worldwide. Highway construction increases the dispersal and invasion of exotic plant species. This study examined the assembly process of the plant communities to determine whether the roadsides of the Patagonian steppe represent a reservoir and dispersal source of invasive exotic species. We analyzed the composition of exotic and native species and functional groups present in the established vegetation and seed banks of roadsides and reference areas nearby. The type of dispersal of exotic and native species at the roadsides was also evaluated. Total cover and that of exotic and native species was lower at the roadsides than in the reference areas; however, at the roadsides the cover and seed abundance of exotic species was higher than that of native species. In the roadsides vegetation, native shrubs such as Acaena splendens predominated, along with exotic perennial herbs and grasses which were mainly represented by Rumex acetosella. In the seed bank the predominant species were exotic perennial herbs, also represented by R. acetosella, annual exotic species such as Epilobium brachycarpum and Verbascum thapsus, and annual native species such as Heliotropium paronychioides. No exotic shrubs were found either at the roadsides or in the reference areas. The species at the roadsides did not present a dominant type of dispersal. The abundance of exotic species at the roadsides, both in the aboveground vegetation and the seed bank, may be due to the stressful environment and the characteristics of the species themselves, such as the ability to form seed banks. This work revealed that the roadsides of the Patagonian steppe constitute reservoirs of invasive exotic species, highlighting the importance of identifying them and controlling their spread, with a view to generating ecosystem management programs. Fil: Chichizola, Giselle Ailin. Universidad Nacional del Comahue. INIBIOMA. CONICET. Laboratorio Ecotono; Argentina. Fil: Gonzalez, Sofía Laura. Universidad Nacional del Comahue. INIBIOMA. CONICET. Laboratorio Ecotono; Argentina. Fil: Rovere, Adiana Edit. Universidad Nacional del Comahue. INIBIOMA. CONICET. Laboratorio Ecotono; Argentina.

Introduction: Isla del Coco is the only island in the Eastern Tropical Pacific with humid tropical forests; 296 plant species are reported, of them, 22% are endemic. Their ecology is poorly understood. Deforestation and the introduction of rats, feral pigs and white-tailed deer are the primary agents of forest degradation. After more than 120 years, the deforested areas have never recovered the native forest. Objective: To analyse if the deforested area keeps its resilience, we evaluated the natural regeneration and ecological processes associated. Methods: From August 2016 to June 2018, we conducted a restoration experiment consisting of a randomized complete blocks design including vegetation cutting, vegetation uprooting and controls as treatments. Plots were protected with an exclusion fence to avoid herbivores. Results: There were no differences between plant cutting and uprooting in stimulating natural regeneration. We only recorded the seedlings of two tree species, 35 individuals of Cecropia pittieri and three of Sacoglottis holdridgei, both endemic. Their regeneration established during the first 15 months mainly. At the end of the experiment, the structure and composition of the vegetation changed from bushes dominated by Entada gigas (28%) and Clidemia strigillosa (12%) to grasses dominated by Paspalum conjugatum (39%). Entada gigas has a high recolonizing potential with a growing rate of 1.6±0.2m/month. Conclusions: As filters for restoration we determined herbivores, which pose a strong negative impact in the development of the forest; the exhausted seed bank of tree species and scarce or null seed dispersion. Resumen Introducción: Isla del Coco es la única isla en el Pacífico oriental con bosques tropicales húmedos, albergando 296 especies de plantas, de las cuales un 22% son endémicas. De su ecología se conoce muy poco. El bosque fue degradado con la introducción de cerdos y venados cola blanca y por deforestación. Las áreas deforestadas hace más de 120 años nunca recuperaron el bosque nativo. Objetivo: Para analizar si el área deforestada mantiene su capacidad de recuperación, se evaluó la regeneración natural y los procesos ecológicos asociados. Metodología: Desde agosto de 2016 hasta junio de 2018, se monitoreó un ensayo de restauración, establecido como un diseño de bloques completos al azar. Los tratamientos incluyeron corte de vegetación, arranque de vegetación y controles. Se utilizó una cerca de exclusión para evitar los herbívoros. Resultados: No hubo diferencias en los tratamientos de corte y arranque de la vegetación para estimular la regeneración natural. Se registró la regeneración de dos especies de árboles: 35 individuos de Cecropia pittieri y tres de Sacoglottis holdridgei, ambas endémicas. La regeneración se estableció principalmente en los primeros 15 meses. Luego de aplicados los tratamientos, la estructura y composición de la vegetación cambió de arbustos dominados por Entada gigas (28%) y Clidemia strigillosa (12%), a pastos dominados por Paspalum conjugatum (39%). Entada gigas tiene el mayor potencial de recolonización por su tasa de crecimiento de 1.6±0.2m/mes. Conclusiones: Los filtros determinados asociados con la regeneración del bosque son los herbívoros; el banco de semillas de las especies arbóreas agotado y la dispersión de semillas escasa o nula, según la especie.

Onagraceae es una familia bien definida de plantas con flores y muy utilizada por el hombre. En Argentina posee numerosas representantes indígenas, distribuidas en 8 géneros y 75 especies, sien-do el 19% de las especies endémicas. Muchas onagráceas son ruderales y facilitan el establecimiento de especies más tardías, siendo útiles para la restauración de áreas degradadas. Dada la importancia de conocer las características de las semillas y de la germinación para su utilización en proyectos de restauración, se indagó sobre aspectos fisiológicos básicos de la germinación de Oenotheraodorata Jacq., hierba ruderal endémica de Argentina. El material se colectó de taludes y bordes de la Ruta Na-cional 40, dentro del éjido municipal de San Carlos de Bariloche, en la Provincia Fitogeográfica Patagónica. La construcción de rutas genera áreas degradadas denudadas de vegetación, donde la especie O. odorata podría utilizarse para iniciar los trabajos de revegetación y consolidar el sustrato. Se evaluó el porcentaje de germinación (G), el tiempo medio de germinación (MGT) y el tiempo hasta el inicio de la germinación (TUG) de un control (C) y de tratamientos pre-germinativos: estra-tificación húmeda fría de 45 días (CMS), escarificación mecánica con bisturí (MS). Los porcentajes de germinación fueron elevados (98% CMS, 96% MS, 93% C), solo se registraron diferencias entre CMS y C. El MGT fue menor en el tratamiento de CMS, respecto al C, pero fue similar al de MS. El TUG fue de 4 días para todos los tratamientos. En conclusión, la especie carece de mecanismos de dormición bajo las condiciones experimentales, lo que sumado al hecho de crecer en ambientes disturbados, ser endémica, y capturar metales pesados, la convierte en una especie propicia para utilizarse en trabajos de restau-ración ecológica en áreas afectadas por el transporte. The Onagraceae are a well-defined family of flowering plants much used by man. Many representatives of this group, which contains 75 species belonging to 8 genera, are indigenous to Argentina, and 19% of these are commonly found throughout the country. Many Onagraceae are ruderal and promote the subsequent establishment of other species, thus contributing to the restoration of degraded areas. Since it is important to know the characteristics of seeds to be used in restoration projects, we studied the basic germination physiology of Oenothera odorata Jacq., a ruderal plant indigenous to Argentina. Material was collected from roadsides and embankments along National highway 40 in the municipality of San Carlos de Bariloche, which lies within the Patagonian phytogeographic province. Road construction generates degraded areas where O. odorata could be used to initiate revegetation and consolidate the substrate. We evaluated percentage germination (G), mean germination time (MGT) and time till initiation of germination (TUG) of a control (C) and of the following pre-germination treatments: 45 days cold moist stratification (CMS) and mechanical scarification with a scalpel (MS). Germination percentages were high (98% CMS, 96% MS, 93% C), with differences recorded only between CMS and C. MGT was lower in the CMS treatment than the control, but similar to MS. TUG was 4 days for all treatments. In conclusion, this species lacks dormancy mechanisms under these experimental conditions, which, together with the fact that it grows in disturbed sites, is endemic, and captures heavy metals, makes it suitable for use in the ecological restoration of areas affected by transport systems. Fil: Chichizola, Giselle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Rovere, Adriana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Gonzalez, Sofia Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina

The objective of this work was to obtain an overview of studies on ecological restoration carried out in Argentina to date. By means of the Scopus database, we performed two literature searches, one in Spanish (restau* and Argentina) and the other in English (restor* and Argentina). Between 1996 and 2013, 105 publications were registered, representing 2% of publications in Biology and Ecology. Most of these appeared in international journals (87%), in English (86%), and 28% were coauthored with researchers from other countries, favoring visibility at an international level. We observed an increase in the number of studies per year over time, with a significant increase beginning in 2008. Of the 18 ecological regions in Argentina, we found studies relating to 12 as well as four studies relating to restoration in urban areas. This review of the literature is intended to increase awareness of restoration in Argentina and help identify current gaps relating either to this subject or to specific ecological regions.

Fil: Zuleta, Gustavo Adolfo. Sociedad Ibero-americana y del Caribe de Restauracion Ecologica; Colombia. Universidad Maimonides; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas; Argentina

Up to now, the processes of domestication of urban landscapes have been little studied. The public green spaces in the city of Bariloche, an enclave with growing urbanization which lies within the Andino Norpatagonica Biosphere Reserve, offer an opportunity to evaluate cultural molding of the environment. We analyzed different management methods of woody species, both in situ and ex situ, in parks located in sectors with different environmental, socioeconomic, size, age and administration characteristics. Our hypotheses were: (1) Species richness will be higher for exotic plants, in accordance with global patterns of ornamental species selection. (2) Species richness and type of management practice will vary according to the kind of environment, the socioeconomic profile of the neighborhood, the age and size of the park, and type of administration (bottom-up or top-down). (3) Bottom-up park administration will lead to a different landscape than top-down administration. Thirty randomly selected parks of both local council and neighborhood administration and varying environmental and socioeconomic conditions were examined and the composition of their woody species identified. In addition, semi-structured and free interviews were carried out with those responsible for park management, both in situ (tolerance, enhancement, protection) and ex situ (sowing, use of cuttings or transplanting). In accordance with our hypothesis, the processes of domestication of the urban landscape show a tendency toward an anthropized diversity of 130 species, mainly exotic in origin (72%), and principally from the Holarctic region (67%). However, multinomial logistic analysis revealed that in parks under neighborhood administration tolerance of native species is higher (13 times) than in parks administrated by the local council. Species richness increases along an environmental and socioeconomic gradient, and with the age of parks, but does not vary with size. We conclude that urban parks are constructed cultural niches which, as in an agroforestry system, are scenarios which reveal processes of incipient domestication that reflect different cosmovisions and drivers typical of multicultural contexts. Fil: Betancurt Ruggirello, Romina Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Rovere, Adriana. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Ladio, Ana Haydee. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina

La restauración ecológica es una disciplina que intenta recuperar atributos perdidos en un ecosistema (diversidad de especies, estructura y función). El objetivo de este trabajo fue evaluar la diversidad de musgos y sus formas de vida en tres ambientes con diferentes niveles de degradación y los sustratos en los que estos se desarrollan. El área de estudio corresponde a un sector que se está restaurando dentro de la Reserva Nacional Lago Puelo. En ella se encuentran tres ambientes distintos: (1) área remanente de bosque maduro de Nothofagus dombeyi, (2) bosque secundario de Austrocedrus chilensis, y (3) matorral dominado por especies exóticas. Se recorrió cada uno de los ambientes, registrando los sustratos con musgos, formas de vida y géneros. Los resultados evidencian una reducción de los sustratos disponibles y de las especies presentes conforme avanza el grado de alteración, desde el área de bosque maduro de N. dombeyi (9 sustratos: 17 géneros: 7 formas de vida), al sector de bosque secundario de A. chilensis (6 sustratos: 8 géneros: 5 formas de vida), siendo menor en el matorral dominado por especies exóticas (1 sustrato: 4 géneros: 3 formas de vida). Los musgos desempeñan funciones importantes en los ecosistemas, son fundamentales en el balance hídrico, pioneros en suelos inestables controlando la erosión y colonizando sitios alterados, sirven como hábitat y alimento para invertebrados, y también constituyen sitios propicios para la germinación de plantas vasculares. Si bien algunas especies leñosas ven afectada su germinación por la presencia de musgos, estos facilitan la germinación de otras especies arbóreas de los bosques templados. Los resultados podrían ser utilizados en restauración, ya sea recreando los sustratos ausentes o realizando traslado de sustratos con musgos, a fin de favorecer la recuperación de áreas boscosas degradadas considerando la biodiversidad original.Ecological restoration is a discipline that seeks to recover the attributes of an ecosystem which have been lost (species diversity, structure and function). The objective of this work was to evaluate the diversity and different life forms of mosses in three environments with varying levels of degradation, as well as the different substrates they grow on. Our study area lies within Lago Puelo National Reserve, in a sector undergoing restoration. Three different environments are found in this sector: (1) a remnant of mature Nothofagus dombeyi forest, (2) secondary Austrocedrus chilensis forest and (3) scrubland dominated by exotic species. Each of these environments was analyzed, and substrates with mosses, life forms and genera were registered. Our results showed a decrease in available substrates and species present as the level of disturbance increased, from the area of mature N. dombeyi forest (9 substrates; 17genera; 7 life forms), followed by the A. chilensis secondary forest (6 substrates: 8 genera: 5 life forms) , to the scrubland dominated by exotic species (1 substrate; 4 genera; 3 life forms). Mosses carry out important functions in ecosystems, as they are essential to the water balance, they are pioneers in unstable soils, where they control erosion and colonize disturbed sites, they provide habitat and food for invertebrates, and also constitute suitable sites for the germination of vascular plants. Although the germination of some woody species is negatively affected by the presence of mosses, the germination of other temperate forest tree species is favored. These results can be useful in restoration, whether for the recreation of absent substrates or the transfer of substrates with mosses, in order to promote the recovery of degraded forest areas to their original levels of biodiversity.

Pollinator-mediated competition through shared pollinators can lead to segregated flowering phenologies, but empirical evidence for the process responsible for this flowering pattern is sparse. During two flowering seasons, we examined whether increasing overlap in flowering phenology decreased conspecific pollination, increased heterospecific pollination, and depressed seed output in the seven species composing a hummingbird-plant assemblage from the temperate forest of southern South America. Overall trends were summarized using meta-analysis. Despite prevailing negative associations, relations between phenological overlap and conspecific pollen receipt varied extensively among species and between years. Heterospecific pollen receipt was low and presumably of limited biological significance. However, our results supported the hypothesis that concurrent flowering promotes interspecific pollen transfer, after accounting for changes in the abundance of conspecific flowers. Seed output was consistently reduced during maximum phenological overlap during the first flowering season because of limited fruit set. Responses varied more during the second year, despite an overall negative trend among species. Relations between estimated effects of phenological overlap on pollination and seed output, however, provided mixed evidence that conspecific pollen loss during pollinator visits to foreign flowers increases pollen limitation. By flowering together, different plant species might benefit each other's pollination by increasing hummingbird recruitment at the landscape level. Nevertheless, our results are mostly consistent with the hypothesis of pollinator-mediated competition shaping the segregated flowering pattern reported previously for this temperate plant assemblage. The mechanisms likely involve effects on male function, whereby pollen-transport loss during heterospecific flower visits limit pollen export, and more variable effects on female function through pollen limitation.

El patrón espacial de la dispersión puede afectar el patrón espacial de establecimiento condicionando la estructura de la vegetación. Este trabajo analiza la magnitud de la dispersión y la colonización (infección) de la planta hemiparásita Misodendrum punctulatum (Misodendraceae). Este estudio fue realizado en un matorral postfuego de Nothofagus antárctica (hospedador). Nuestra hipótesis plantea que el patrón de dispersión anemófila de las semillas de M. punctulatum condiciona el patrón de infección (colonización) sobre N. antárctica y que ambos procesos (dispersión y colonización) son asimétrico en la misma dirección en función del viento predominante. Se evaluó la dispersión a campo contando el número de semillas sobre troncos y ramas desde arbustos remanentes infectados (hospedadores focales) hacia cada punto cardinal. La colonización se evaluó registrando el número de infecciones sobre cada hospedador a lo largo de franjas trazadas hacia cada orientación desde los arbustos focales. Se observó que la cantidad de semillas dispersadas declina con la distancia desde la fuente de semillas, ajustándose a una distribución exponencial negativa. La mayor distancia de dispersión primaria fue de 10 m hacia el este. Respecto a la colonización la mayor distancia de nuevos establecimientos fue 22.5 m en dirección sur. Por otro lado, el número de infecciones desde los arbustos focales fue menor al oeste (1 infectado: 10 no infectados) que en las otras direcciones (1 infectado: 6 no infectados). Ambos procesos presentaron un patrón de distribución similar y asimétrica como consecuencia de la dirección de los vientos predominantes y se observó una alta correlación espacial entre la dispersión de semillas y el establecimiento de las infecciones. Estos resultados de dispersión y colonización permiten comprender los patrones de distribución espacial de esta planta hemiparásita y entender su dinámica de infección. Los resultados de este trabajo podrían ser útiles en proyectos de restauración ecológica, por ejemplo para la reintroducción de M. puctulatum sobre ejemplares de N. antárctica que rebrotan en matorrales postfuegos. Estos aspectos estudiados también aportan al conocimiento de esta interacción ecológica que ocurre frecuentemente en los bosques de Nothofagus de Argentina y Chile.Spatial dispersal pattern could determine the spatial pattern of establishment affecting the vegetation structure. Our work, analyze dispersion and colonization attribute of the hemiparasitic plant Misodendrum punctulatum (Misodendraceae). Our hypothesis outline that the wind dispersal pattern of M. punctulatum seeds determine the infection pattern (colonization) on Nothofagus antárctica, and both processes (dispersión and colonization) are asymmetric in accordance with the predominant wind direction. This study was carry out in a N. antárctica (host) post-fire shrubland. We assessed the seed dispersal estimating number of seed on host branches supplied from infected-survivals hosts (focal host) toward each cardinal direction. Colonization was assessed estimating number of infections on each host, through transects, at every cardinal direction from the focal host. We observed that seeds dispersed decline with distances from the seed source, and dispersion fitted to a negative exponential model. The longest distance of primary dispersion observed was 10 m toward east. About colonization, longest distance from the focal host was 22.5 m toward south. Furthermore, ratio of infected host was lesser on west, one infected by 10 uninfected (1:10) than other compass aspects (1:6). Both process, dispersion and colonization, showed a similar and asymmetric pattern of distribution, which could be result of wind direction predominant from northwest. In addition, a high spatial correlation was observed among number of seed dispersed and recruitment of infection in distances from the sources of seeds. Our results allow understand the patterns of spatial distribution and infection dynamics of Misodendrum punctulatum. In order to plan management strategies, understanding the infection dynamics is useful to perform successfully strategies to the control of hemiparasitic plants in forest to commercial use, and conservation or restoration strategies, e.g. to restorate this hemiparasitic specie in areas recently colonized by N. antárctica. These studied aspects in Misodendrum punctulatum contribute to the knowledge of this ecological interaction, which is frequent in Nothofagus forests from Argentina and Chile.

Deforestation of temperate forests has created landscapes of forest remnants in matrices of intense human use. We studied the genetic effects of fragmentation in southern Chile on Embothrium coccineum J.R. et G. Forster, an early colonizing, bird-pollinated tree. We tested the hypothesis that, because of its self-incompatibility and life-history strategy, E. coccineum is less strongly affected by fragmentation. We studied the effects of reduced population size and increased isolation on population genetic structure and early performance of progeny. Samples were collected from spatially isolated trees and six fragments of differing sizes (small, 1 ha; medium, 20 ha; large, >150 ha). Based on isozyme polymorphisms we estimated parameters of genetic diversity, divergence, and inbreeding for adults and greenhouse-grown progeny. We also measured germination, seedling growth, and outcrossing rates on progeny arrays. Genetic variation of adults did not correlate significantly with population size, as expected, given that fragmentation occurred relatively recently. Weak effects of fragmentation were measured on progeny. Only adults yielded significant inbreeding. Similar total genetic diversity was found in adults and progeny. Low but significant genetic differentiation existed among adult and progeny populations. Seedling growth correlated positively with the effective number of alleles, showing deleterious effects of inbreeding on progeny. Seeds from small fragments had the highest outcrossing rates and germination success, indicating that higher pollinator activity in such fragments reduced selfing, thereby buffering genetic erosion and maintaining adaptive variation. The effects of forest fragmentation were detectable in E. coccineum, but these effects will probably not be detrimental to the viability of remnant populations because small, fragmented populations demonstrated higher levels of gene flow and lower inbreeding than larger stands. Pioneer species that are insensitive to forest clearing may be crucial in recovery plans to facilitate the establishment of species intolerant to such disturbance.

Plant breeding systems are considered to reflect species' life history characteristics, selection due to biotic or abiotic factors, pollination conditions, or a combination of these. Reproductive systems may vary over ecological gradients. The breeding system of the ornithophilous Embothrium coccineum (Proteaceae) from temperate South America was studied by pollination treatments: manual self-pollination, manual cross-pollination, automatic self-pollination, and natural pollination. These treatments were conducted in a coastal western and an Andean eastern population. Embothrium coccineum was found to be self-incompatible and highly dependent on the pollinating agent at both sites. However, pollen limitations were greater in the coastal population, as breeding efficiency was lower. Populations have different floral visitors whose identity differentially affects reproductive efficiency and pollen flow in E. coccineumLos sistemas de compatibilidad reproductiva en las plantas son considerados una manifestación de la historia de vida, de la selección ante factores abióticos ó bióticos, de las condiciones de polinización o una de combinación de esos factores. El sistema reproductivo de una especie puede variar a lo largo de un gradiente ecológico-ambiental. El sistema reproductivo de Embothrium coccineum (Proteaceae), un árbol ornitófilo endémico de los bosques templados de sur de Sudamérica, fue estudiado mediante experimentos de polinización: autopolinización manual, polinización manual cruzada, autopolinización automática y polinización natural en flores descubiertas. Este trabajo se realizó en una población costera al oeste de la cordillera de los Andes y una población andina ubicada al este de la cordillera de los Andes. En ambas poblaciones se encontró que E. coccineum es autoimcompatible y altamente dependiente de los agentes polinizadores en ambos sitios. Sin embargo, la limitación por polen fue mayor en la población costera, donde la eficiencia reproductiva fue menor. Las poblaciones tienen diferentes visitantes florales cuya identidad afecta diferencialmente la eficiencia reproductiva y el flujo de polen en E. coccineum

In dioecious plants, males and females usually differ in the amount of resources devoted to reproduction. As a consequence of potential tradeoffs between reproductive and vegetative functions, sexe...

The effects of Pleistocene glaciations on the genetic characteristics of the most austral conifer in the world, Pilgerodendron uviferum, were analysed with specific reference to the hypothesis that the species persisted locally in ice-free areas in temperate South America. It was expected that genetic variation would decrease with latitude, given that ice fields were larger in southern Patagonia and thus refugia were probably located towards the northern distributional limit of the species as suggested by the fossil record. In addition, an increase in among-population genetic divergence was expected with increasing distance to putative glacial refugia. We examined the relationship between location and within-population variability indices of 20 Pilgerodendron populations derived from isozyme analyses. We analysed possible refugia hypotheses by the distribution of allele frequencies using multivariate discriminant analysis. The degree of genetic differentiation with geographical distance between all population pairs was investigated by Mantel tests. Results indicated that Pilgerodendron populations are highly monomorphic, probably reflecting past population bottlenecks and reduced gene flow. Southernmost populations tend to be the least genetically variable and were therefore probably more affected by glacial activity than northern ones. Populations located outside ice limits seem to have been isolated during the glacial period. The presence of centres of genetic diversity, together with the lack of a significant correlation between genetic and geographical distances and the absence of geographical patterns of allelic frequencies at most analysed alleles, may indicate that Pilgerodendron did not advance southward after the last glaciation from a unique northern refugium, but spread from several surviving populations in ice-free areas in Patagonia instead.

Pilgerodendron uviferum (Don) Flor., Cupressaceae (common name "cipres de las Guaitecas") is the native conifer with the widest geographic range in the temperate forests in southern South America, particularly when compared with its only two close relatives, Austrocedrus chilensis ((Don) Florin et Boutleje) and Fitzroya cupressoides ((Mol.) Johnst.). In Argentina, Pilgerodendron is restricted to a small number of isolated populations along its distribution. This study analyzes the conservation status of known Pilgerodendron populations in Argentina, based on information about the physical characteristics of the habitats, vegetation and disturbance types in eight different locations. The majority of the studied populations are protected within national parks, where they are generally restricted to waterlogged sites, and they consist of small groups of individual trees and not continuous forests. At some of the locations, signs of human-induced disturbances were observed, mainly logging or browsing by cattle. This was the case for the Cordon Serrucho population, which is not currently included in any protected area. Adequate strategies for a better preservation and restoration of degraded Pilgerodendron populations include cattle grazing exclusion and the creation of a protected area.

This study evaluated the effects of several environmental parameters on seedling survival in Cypress of the Cordillera (Austrocedrus chilensis) both in the greenhouse and in the forest. In the greenhouse studies, seedling survival was evaluated under different irrigation and light regimes In the forest, association of seedlings with vegetation cover was analyzed. Although adult cypress trees are regarded as intolerant to shade, regeneration appeared to require conditions other of light. The intolerance of cypress to shade varied with growth phase, becoming more emphasized in the adult phase. It is concluded that in the greenhouse and in the forest, cypress regeneration takes place mainly under conditions that are protected from desiccation.

We scored the proportion of aborted pollen, age, and diameter at breast height of 78 male trees of the south-Andean dioecious conifer, Austrocedrus chilensis. Although the proportion of aborted pollen was low (range = 0.5%-7.8%), it increased significantly with tree age and size (r = .459 and .467, respectively). The independent effects of these two variables could not be evaluated, however, because of high colinearity between them. Tree reproductive effort and mean size of viable pollen grains, variables that could reflect resource availability and physiological stress, did not account for any significant part of the variation in the proportion of aborted pollen. Neither did these variables covary with tree age or size. To the extent that pollen abortion in this species is due to genetic causes, these results support a qualitative prediction of the "genetic load-with-age accumulation model," which asserts that pollen viability should decrease with aging.

La restauracion ecologica es una disciplina que intenta recuperar atributos perdidos en un ecosistema (diversidad de especies, estructura y funcion). El objetivo de este trabajo fue evaluar la diversidad de musgos y sus formas de vida en tres ambientes con diferentes niveles de degradacion y los sustratos en los que estos se desarrollan. El area de estudio corresponde a un sector que se esta restaurando dentro de la Reserva Nacional Lago Puelo. En ella se encuentran tres ambientes distintos: (1) area remanente de bosque maduro de Nothofagus dombeyi, (2) bosque secundario de Austrocedrus chilensis, y (3) matorral dominado por especies exoticas. Se recorrio cada uno de los ambientes, registrando los sustratos con musgos, formas de vida y generos. Los resultados evidencian una reduccion de los sustratos disponibles y de las especies presentes conforme avanza el grado de alteracion, desde el area de bosque maduro de N. dombeyi (9 sustratos: 17 generos: 7 formas de vida), al sector de bosque secundario de A. chilensis (6 sustratos: 8 generos: 5 formas de vida), siendo menor en el matorral dominado por especies exoticas (1 sustrato: 4 generos: 3 formas de vida). Los musgos desempenan funciones importantes en los ecosistemas, son fundamentales en el balance hidrico, pioneros en suelos inestables controlando la erosion y colonizando sitios alterados, sirven como habitat y alimento para invertebrados, y tambien constituyen sitios propicios para la germinacion de plantas vasculares. Si bien algunas especies lenosas ven afectada su germinacion por la presencia de musgos, estos facilitan la germinacion de otras especies arboreas de los bosques templados. Los resultados podrian ser utilizados en restauracion, ya sea recreando los sustratos ausentes o realizando traslado de sustratos con musgos, a fin de favorecer la recuperacion de areas boscosas degradadas considerando la biodiversidad original.

El patrón espacial de la dispersión puede afectar el patrón espacial de establecimiento condicionando la estructura de la vegetación. Este trabajo analiza la magnitud de la dispersión y la colonización (infección) de la planta hemiparásita Misodendrum punctulatum (Misodendraceae). Este estudio fue realizado en un matorral postfuego de Nothofagus antárctica (hospedador). Nuestra hipótesis plantea que el patrón de dispersión anemófila de las semillas de M. punctulatum condiciona el patrón de infección (colonización) sobre N. antárctica y que ambos procesos (dispersión y colonización) son asimétrico en la misma dirección en función del viento predominante. Se evaluó la dispersión a campo contando el número de semillas sobre troncos y ramas desde arbustos remanentes infectados (hospedadores focales) hacia cada punto cardinal. La colonización se evaluó registrando el número de infecciones sobre cada hospedador a lo largo de franjas trazadas hacia cada orientación desde los arbustos focales. Se observó que la cantidad de semillas dispersadas declina con la distancia desde la fuente de semillas, ajustándose a una distribución exponencial negativa. La mayor distancia de dispersión primaria fue de 10 m hacia el este. Respecto a la colonización la mayor distancia de nuevos establecimientos fue 22.5 m en dirección sur. Por otro lado, el número de infecciones desde los arbustos focales fue menor al oeste (1 infectado: 10 no infectados) que en las otras direcciones (1 infectado: 6 no infectados). Ambos procesos presentaron un patrón de distribución similar y asimétrica como consecuencia de la dirección de los vientos predominantes y se observó una alta correlación espacial entre la dispersión de semillas y el establecimiento de las infecciones. Estos resultados de dispersión y colonización permiten comprender los patrones de distribución espacial de esta planta hemiparásita y entender su dinámica de infección. Los resultados de este trabajo podrían ser útiles en proyectos de restauración ecológica, por ejemplo para la reintroducción de M. puctulatum sobre ejemplares de N. antárctica que rebrotan en matorrales postfuegos. Estos aspectos estudiados también aportan al conocimiento de esta interacción ecológica que ocurre frecuentemente en los bosques de Nothofagus de Argentina y Chile. Spatial dispersal pattern could determine the spatial pattern of establishment affecting the vegetation structure. Our work, analyze dispersion and colonization attribute of the hemiparasitic plant Misodendrum punctulatum (Misodendraceae). Our hypothesis outline that the wind dispersal pattern of M. punctulatum seeds determine the infection pattern (colonization) on Nothofagus antárctica, and both processes (dispersión and colonization) are asymmetric in accordance with the predominant wind direction. This study was carry out in a N. antárctica (host) post-fire shrubland. We assessed the seed dispersal estimating number of seed on host branches supplied from infected-survivals hosts (focal host) toward each cardinal direction. Colonization was assessed estimating number of infections on each host, through transects, at every cardinal direction from the focal host. We observed that seeds dispersed decline with distances from the seed source, and dispersion fitted to a negative exponential model. The longest distance of primary dispersion observed was 10 m toward east. About colonization, longest distance from the focal host was 22.5 m toward south. Furthermore, ratio of infected host was lesser on west, one infected by 10 uninfected (1:10) than other compass aspects (1:6). Both process, dispersion and colonization, showed a similar and asymmetric pattern of distribution, which could be result of wind direction predominant from northwest. In addition, a high spatial correlation was observed among number of seed dispersed and recruitment of infection in distances from the sources of seeds. Our results allow understand the patterns of spatial distribution and infection dynamics of Misodendrum punctulatum. In order to plan management strategies, understanding the infection dynamics is useful to perform successfully strategies to the control of hemiparasitic plants in forest to commercial use, and conservation or restoration strategies, e.g. to restorate this hemiparasitic specie in areas recently colonized by N. antárctica. These studied aspects in Misodendrum punctulatum contribute to the knowledge of this ecological interaction, which is frequent in Nothofagus forests from Argentina and Chile. Fil: Tercero Bucardo, Norlan. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Laboratorio de Ecotono; Argentina Fil: Rovere, Adriana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche. Laboratorio de Ecotono; Argentina

Temperate and tropical montane forests in Latin America represent a major natural resource at both regional and national levels for a number of reasons - biological, climatic, economic, cultural. Native tree species in these forests share conservation problems because of deforestation, habitat degradation, overall biodiversity loss and integrity of landscape structure. However, literature on forest restoration research and practices in these ecosystems is scanty and dispersed. We integrate forest restoration experiences aimed at a variety of purposes that allow us to gain insight over several years under contrasting ecological, social and economic conditions in six study regions: the Argentinian Andes, the IX and X Regions in Chile (including northern Chiloe Island), and central Veracruz and the central and northern Highlands of Chiapas (Mexico). By comparing analogous conditions and highlighting differences among the study sites, current pitfalls can be identified and used to define a minimum set of elements to be considered in a protocol for restoration practices. The restoration studies reviewed here include a wide variety of ecological and socio-economic circumstances that allow the identification of broad guidelines, criteria and indicators for planning, implementing and monitoring ecological restoration programmes. We conclude with statements that suggest approaches, strategies and concrete actions that might be considered as lessons learned and inputs for best practice in forest restoration research and programmes conducted in other developing regions.

Los sistemas de compatibilidad reproductiva en las plantas son considerados una manifestacion de la historia de vida, de la seleccion ante factores abioticos o bioticos, de las condiciones de polinizacion o una de combinacion de esos factores. El sistema reproductivo de una especie puede variar a lo largo de un gradiente ecologico-ambiental. El sistema reproductivo de Embothrium coccineum (Proteaceae), un arbol ornitofilo endemico de los bosques templados de sur de Sudamerica, fue estudiado mediante experimentos de polinizacion: autopolinizacion manual, polinizacion manual cruzada, autopolinizacion automatica y polinizacion natural en flores descubiertas. Este trabajo se realizo en una poblacion costera al oeste de la cordillera de los Andes y una poblacion andina ubicada al este de la cordillera de los Andes. En ambas poblaciones se encontro que E. coccineum es autoimcompatible y altamente dependiente de los agentes polinizadores en ambos sitios. Sin embargo, la limitacion por polen fue mayor en la poblacion costera, donde la eficiencia reproductiva fue menor. Las poblaciones tienen diferentes visitantes florales cuya identidad afecta diferencialmente la eficiencia reproductiva y el flujo de polen en E. coccineum