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Métodos fitoecológicos aplicados en la caracterización de ecosistemas de referencia
Se caracterizó ecosistemas de referencia de acuerdo a su composición florística en dos áreas con evidentes signos de degradación; predio Pumillahue, ubicado en la comuna de Panguipulli, Región de Los Ríos y Reserva Nacional China Muerta, ubicada en la comuna de Melipeuco, Región de La Araucanía. Para tal efecto se estableció un numero variable de parcelas donde se identificó a todas las especies de plantas vasculares, se calculó su riqueza y abundancia y se realizó un análisis de ordenamiento con el fin de conocer la distribución de las áreas muestrales de acuerdo a su composición florística.
Urrutia Estrada, Jonathan-Fuentes-Ramírez, Andrés
2019
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
Incorporando la multifuncionalidad en la evaluación económica de proyectos de restauración de bosques nativos siempreverdes en el sur de Chile
Se evaluó la factibilidad económica de implementar iniciativas de restauración de bosques del Tipo Forestal Siempreverde, incorporando un análisis de costos y beneficios asociados a la ejecución de las actividades de manejo forestal y los retornos económicos potenciales por la comercialización de madera y de los servicios ecosistémicos secuestro de carbono y producción de miel.
Schlegel Heldt, Bastienne-Little Cárdenas, Christian-Urrutia, Matías-Hernández, Germán-Pasten, Roberto
2020
The recruitment of the recalcitrant-seeded Cryptocarya alba (Mol.) Looser, established via direct seeding is mainly affected by the seed source and forest cover
Natural regeneration of recalcitrant-seeded tree species is strongly limited in Mediterraneantype climate zones due to increasing droughts imposed by climate change. Direct seeding can be a low-cost alternative to seedling establishment, but there is still limited information for some species. This study aimed to assess the effects of the seed source and forest cover on the germination and survival of the endemic Cryptocarya alba Mol. established through direct seeding. Three habitat types differing in forest cover were identified within the natural park Reserva Natural Altos de Cantillana, Metropolitan Region, Chile. The forest cover corresponded to open (canopy density <25%), semidense (canopy density around 50%), and dense forest (canopy density >75%). All forest cover had C. alba as one of the dominant species. At each habitat type, 38 families from four seed sources (Cuesta La Dormida (CD), Antumapu (AN), Cantillana (CA, local seed source) and Cayumanque (CY)) were directly seeded. Germination (Germin) and survival (Surv) were evaluated weekly during one growing season. There were significant differences between seed sources in Germin and Surv, with means values varying from 7.8% to 37% for Germin and 0% to 20% for Surv. The local seed source CA had the highest values in both traits. A significant variation was also observed between families within seed sources only for Germin. The dense forest cover had the highest Germin (22%) and Surv (55%) results compared to the other forest cover types, which was partially associated with differences in soil moisture, temperature, and bulk density. Due to the most frequent droughts in these Mediterranean-type climate zones, the use of local seeds on dense forest cover is recommended for the direct seeding of the species in the initial recruitment.
Magni, Carlos R.-Saavedra, Nicole-Espinoza, Sergio E.-Yañez, Marco A.-Quiroz Marchant, Iván-Faúndez, Angela F.-Grez M., Iván-Martínez, Eduardo E.
Región Metropolitana de Santiago
2022
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
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
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
Monitoreo a corto y largo plazo en ensayos de restauración de la conífera longeva y de lento crecimiento Pilgerodendron uviferum
El monitoreo a largo plazo es fundamental para comprender las respuestas a acciones de restauración en especies de lento crecimiento como la conífera nativa Pilgerodendron uviferum. Luego de incendios catastróficos, la mayoría de los árboles y semillas de esta especie fueron eliminados, restringiendo su recuperación natural. El objetivo de este estudio fue analizar las implicancias del monitoreo a corto y largo plazo en la interpretación de resultados en ensayos de restauración pasiva y activa de Pilgerodendron uviferum, posterior a incendios en la Isla de Chiloé. Durante 10 años se evaluó la producción de semillas, el reclutamiento natural, y la regeneración asistida mediante plantaciones de P. uviferum bajo diferentes condiciones de micrositio en bosque turbosos y luminosidad en bosque de mejor drenaje. La producción de semillas de P. uviferum fue irregular y abundante cada siete años (~200 semillas m-2). La regeneración natural luego de ocho años aumentó en un 80 %, principalmente en sustratos cubiertos con musgos y en asociación con Donatia fascicularis y Astelia pumilia. La abundancia de regeneración natural estuvo positivamente asociada a árboles semilleros de mayor edad, la altura y diámetro de las plantas fue favorecida por la protección arbustiva. En sitios turbosos, la plantación en camellones alcanzó mayores tasas de sobrevivencia (78 %) y en sitios con mejor drenaje, fue mayor bajo protección de dosel superior (100 %). Los resultados sugieren que especies de lento crecimiento como P. uviferum requieren de periodos prologados de monitoreo para interpretar adecuadamente los resultados de ensayos de restauración en bosques quemados.
Galindo Castillo, Nicole-Bannister, Jan R.-Laage, Katharina
Región de Los Lagos
2021
Crecimiento y supervivencia de cinco especies nativas en un ensayo de plantación con consideraciones genéticas, en bosque siempreverde estructuralmente alterado
Se analizó una medición de altura y supervivencia, al tercer año de crecimiento en terreno, de un ensayo de plantación de cinco especies nativas: ulmo (Eucryphia cordifolia) y lingue (Persea lingue) a nivel de progenies, y tepa (Laureliopsis philippiana), roble (Nothofagus obliqua) y olivillo (Aextoxicon punctatum) como grupos diversos representativos del bosque local. Todas ellas plantadas en fajas habilitadas en quilantales de un bosque siempreverde severamente degradado en la provincia de Valdivia, Chile. Con los datos de la medición se efectuó el análisis descriptivo del ensayo y una evaluación estadística usando análisis de varianza y pruebas de comparación múltiple (Tuckey), para evaluar el efecto de la densidad de plantación y de la proporción de especies intolerantes/tolerantes sobre el crecimiento y supervivencia de las plantas, para un nivel de significancia de 0,05%.
Gutiérrez Caro, Braulio-Ipinza Carmona, Roberto
Región de Los Ríos
2023
Phylogeographic origin authentication of Araucaria araucana (Mol.) K Koch seedlings through the application of spectroscopy techniques in different infrared ranges and chemometric methods
The origin of seed and seedlings is an important factor for the success of restoration programs; an inadequate origin can have negative impacts on genetic and adaptive processes. A technique that allows authenticating the origin is infrared spectroscopy, a fast, accurate and low-cost tool. In Patagonia one species that required restoration programs, consequently, propagules traceability is Araucaria araucana. Phylogeographic studies showed significant differences between Chilean Andean and Coastal populations. The goal of this study was to discriminate the phylogeographic origin of A. araucana seedlings using spectroscopic and chemometric methods. Seedlings of both phylogeographic origins were cultivated in common garden and spectral information in four spectral ranges was recorded. Principal component analysis and soft independent modeling of class analogy (SIMCA) were applied. All the spectral ranges analyzed were able to discriminate phylogeographic origin, whose predictive models achieved a classification accuracy of 88–91%. The best models were SIMCA VIS–NIR and SIMCA FTIR. Wavelengths responsible for discrimination were associated with photosynthetic pigments, proteins and plant fibers. Andean seedlings have a higher content of Chlb, xanthophylls and plant fibers and the most important bands for the Coastal provenance are related to Chla and protein contents. It is shown that differences reported at the genetic level between both origins are expressed at the chemical level. In conclusion, infrared spectra obtained from Araucaria araucana, treated with chemometric methods, allow capturing the phylogeographic signal that separates Coastal and Andean origins. In the future, the resulting models could be used in restoration programs for this species.
Rojas, Macarena-Castillo, Rosario-González Campos, Jorge-Ipinza Carmona, Roberto-Sanhueza, M.-Hasbún, Rodrigo
2022

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