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Author: Acevedo Tapia, Manuel × Subject: RESTAURACION ×

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Now showing 1 - 5 of 5
  • Artículo de revista
    Shrub influences on seedling performance when restoring the slow‐growing conifer Pilgerodendron uviferum in southern bog forests
    Forest restoration is most efficient if it can take advantage of facilitative interactions between established vegetation and planted trees. However, positive and negative interactions have been identified in a number of plant communities. After centuries of anthropogenic fires, forest recovery has been extremely slow in southern bog forests previously dominated by the slow‐growing and vulnerable conifer Pilgerodendron uviferum on Chiloé Island, Chile. Today, the landscape is dominated by secondary shrublands with scattered patches of Sphagnum moss and limited natural tree regeneration. We hypothesized that the retention of secondary shrubs facilitates the early performance of P. uviferum restoration plantings by providing better microsite conditions. To test this hypothesis, we compared the response of seedlings planted on sites prepared at two levels of intervention: after shrubs had been removed or where shrubs were retained. Shrub retention showed a nurse‐plant effect on P. uviferum seedlings 4 years after planting, which resulted in reduced physiological stress (measured as Fv/Fm) for seedlings, as well as reduced browsing. Consequently, the seedlings growing in areas with shrub retention had larger height increment and higher vitality than those in areas where shrubs had been removed. Thus, the more open micro‐site conditions created by shrub removal resulted in generally poorer seedling performance, although seedling mortality—which was low overall (approximately 2–4%)—showed no significant difference between the two levels of intervention. These findings have direct implications for the restoration of slow‐growing conifers that can tolerate extreme wet conditions in highly degraded forests.
    Bannister, Jan R.-Travieso, Germán-Galindo Castillo, Nicole-Acevedo Tapia, Manuel-Puettmann, Klaus J.-Salas Eljatib, Christian
    2020
  • Artículo de revista
    Intraspecific variation in drought response of three populations of Cryptocarya alba and Persea lingue, two native species from mediterranean Central Chile
    An increase in the severity of drought events on Mediterranean climates highlights the need of using plant material adapted to drought during restoration efforts. Thus, we investigated between-population morpho-physiological differences in Cryptocarya alba and Persea lingue, two native species from Mediterranean central Chile, for traits that could effectively discriminate population performance in response to water restriction (WR) testing. Three populations from each species were subjected to WR treatment and physiological, morphological, and growth parameters were assessed at the beginning and at the end of the experiment. In C. alba, the most xeric population displayed smaller plants with mesophyllous leaves and lower photosynthetic rates indicating a resource saving strategy. Moreover, the xeric population performed better during WR than the most mesic populations, exhibiting higher water use efficiency (iWUE) and maintenance of growth rates. All C. alba populations responded equally to WR in terms of morphology and biomass partitioning. In contrast, differences among P. lingue populations were subtle at the morpho-physiological level with no apparent relation to provenance environmental conditions, and no morphological traits were affected by WR. However, in response to WR application, the most mesic population was, as observed through reduction in relative growth rates, more affected than xeric populations. We attribute such discrete differences between P. lingue provenances to the lower distributional range of selected populations. Our results show that relative growth rates in both species, and iWUE only in C. alba, exhibited population specific responses upon WR imposition; these results correspond with the environmental conditions found at the origin of each populations. Both traits could further assist in the selection of populations for restoration according to their response to water stress.
    Álvarez, Carolina-Acevedo Tapia, Manuel-Dumroese, R. Kasten-González Ortega, Marta-Cartes Rodríguez, Eduardo
    2020
  • Artículo de revista
    Production and establishment techniques for the restoration of Nothofagus alessandrii, an endangered keystone species in a Mediterranean forest
    Ruil (Nothofagus alessandrii) is an endangered keystone species from the Mediterranean climate zone of Chile. Ruil’s fragile state of conservation urges development of restoration programs, but specific protocols for nursery production and field establishment that ensure plant survival are largely unknown. Therefore, we examined the effect on nitrogen (N) fertilization and container size during nursery production in combination with the use of mesh shelters after outplanting on survival and growth during the first growing season in the field. First year outplanting survival of nursery-grown container seedlings was enhanced when seedlings were given nitrogen (N) during nursery production and deployed with mesh tree shelters in the field. The volume of the container had no effect on outplanting survival and growth. Increasing N from zero to 200 mg N L−1 provided sufficient N levels, resulting in increased seedling height, root-collar diameter, shoot biomass, and total seedling N and phosphorous concentrations. Additional N provided by the 400 and 600 mg N L−1 treatments underwent luxury consumption by the seedlings with no further benefits in field performance. Improved growth in the nursery, along with the use of mesh tree shelters after outplanting, especially during the typical summer drought, may be responsible for increased survival during the first growing season. Increasing the performance of nursery-grown ruil seedlings is essential to restoring this endangered, vulnerable, and foundation species within the highly biodiverse, yet seriously threatened endemic Maulino Costero Forest of the Mediterranean climate of central Chile.
    Acevedo Tapia, Manuel-Álvarez, Carolina-Cartes Rodríguez, Eduardo-Dumroese, R. Kasten-González Ortega, Marta
    2020
  • Artículo de revista
    Efecto de la concentración de fósforo y calcio sobre atributos morfo-fisiológicos y potencial de crecimiento radical en plantas de Aextoxicon punctatum producidas a raíz cubierta en la etapa de endurecimiento
    El objetivo de este estudio es determinar el efecto de diferentes concentraciones de fósforo y calcio en la etapa de endurecimiento en vivero, sobre atributos morfológicos (longitud de tallo, diámetro de cuello, área foliar), fisiológicos (estatus nutricional) y potencial de crecimiento radical (largo y número de raíces nuevas) de plantas de olivillo (Aextoxicon punctatum) producidas a raíz cubierta. Se definieron nueve esquemas nutricionales que variaron fósforo y calcio en tres concentraciones cada uno (0, 150 y 300 mg L-1) Luego de 13 semanas, periodo de endurecimiento, no se observaron diferencias significativas entre los tratamientos para las variables morfológicas y de potencial de crecimiento raíces. Sin embargo, tratamientos con aplicaciones de 300 mg L-1 de fósforo generaron las mayores concentraciones a nivel foliar de nitrógeno y las menores de calcio. Dosis de 300 mg L-1 de calcio aplicadas en el medio determinaron una mayor concentración foliar del mismo elemento, y un mayor número de raíces y más largas.
    González Ortega, Marta-Ríos L., Darcy-Peña-Rojas, Karen-García Rivas, Edison-Acevedo Tapia, Manuel-Cartes Rodríguez, Eduardo-Sánchez-Olate, Manuel
    2020
  • Artículo de revista
    The influence of microsite conditions on early performance of planted Nothofagus nitida seedlings when restoring degraded coastal temperate rain forests
    Widespread impacts of changes in land use, climate, and disturbance regimes continue to affect mature forests and their subsequent post-disturbance recovery. In South American temperate rainforests, the recovery of the original composition, structure, and ecological services of now-degraded old-growth forests is additionally hampered by the aggressive competition that the native Chusquea bamboo understory exerts on juvenile trees, thus arresting ecological succession. In this study, we aim to evaluate the early performance of Nothofagus nitida seedlings (pioneer tree species that tolerate shade) planted beneath nurse canopy following removal of the understory, and to define which microsite conditions can facilitate N. nitida growth. For this, we monitored 45 N. nitida plantings established in 2014 in Chiloé Island (North Patagonia, Chile) for five years. After this period, planted seedlings presented relatively good indicators of performance with low mortality (~30% of dead seedlings), good vitality (~60% of healthy seedlings), and relatively high mean periodic annual increments in root collar diameter and height (~1.7 mm/year and ~17.4 cm/year, respectively). Furthermore, our results show that the planted N. nitida seedlings can tolerate and grow under low-light conditions, though their diameter and height increase significantly with higher light availability. However, physiological stress of planted seedlings increased in open areas with more available light and planted seedlings were most stressed during the summer season. Increased summer-season stress was attributed to the months with highest depth of the water table, highest maximum and mean photosynthetic active radiation (PAR) values, highest temperature, and lowest precipitation. Our results show for first time with field-based data that different microsite and canopy conditions facilitate the initial performance of N. nitida plantings after removal of the Chusquea bamboo understory. In this context, we conclude that the removal of the Chusquea bamboo understory is the key to overcome arrested succession of coastal temperate rain forests Furthermore, supplementary planting of pioneer tree species that tolerate shade, like N. nitida, assists natural forest recovery, especially in humid and open sites with some protection of a nurse canopy.
    Bannister, Jan R.-Acevedo Tapia, Manuel-Travieso, Germán-Holz, Andrés-Galindo Castillo, Nicole
    Región de Los Lagos
    2021