4 results
Search Results
Now showing 1 - 4 of 4
Long-Term Effects of Copper Mine Tailings on Surrounding Soils and Sclerophyllous Vegetation in Central ChileArtículo de revistaThis study analyzed the nutrients and metals concentrations of the surrounding soils and sclerophyllous vegetation of a tailing at the CODELCO–El Teniente copper mine in Central Chile. The content of metal, macro-, and micronutrients were analyzed in the soils outward from the tailing till 60-m distance at depths of 30, 60, and 90 cm, and in the foliage and stems of the native vegetation associated to the tailing. At plant level, we measured height, diameter, level of damage, and physiological attributes. Cu, Ni, Cr, and As were higher in the tailing, whereas soil Mn and Fe were higher at 60 m from the tailing. Soil K was higher at 30-cm depth, whereas Na was higher at 90-cm depth. Foliar Cu was higher in Acacia caven (40.5 mg kg−1), whereas the levels of Cu and Zn in stems were higher in Quillaja saponaria (6.5 mg kg−1 for Cu and 13.1 mg kg−1 for Zn). As the values of water potential and quantum efficiency of the photosystem II averaged − 1.1 MPa and 0.73, respectively, these two species exhibited no physiological stress. Only Q. saponaria tended to increase the level of damage at higher distances from the tailing. A. caven and Q. saponaria exhibited foliar contents of Cu and Fe considered toxic (Cu from 18.5 to 40.5 and Fe from 298 to 407 mg kg−1); however, both species were able to prosper at the limit of the tailing. Migración asistida de Araucaria araucana, un estudio de caso en ChileArtículo de revistaLa Araucaria araucana es una especie emblemática de los bosques de Chile y Argentina. En estos últimos años esta especie está siendo sometida a una fuerte presión de selección debida al cambio climático, el que ha predispuesto al daño foliar de la araucaria (DFA), enfermedad que está comprometiendo el 85% de las poblaciones chilenas, lo que ha cambiado su estado de conservación de vulnerable a en vías de extinción, en especial las procedencias de la cordillera de la costa. Dado este escenario se está ejecutando un programa de migración asistida de esta especie, para lo que se han seleccionado 450 madres a lo largo de su distribución natural, se han recogido semillas que se han viverizado manteniendo la estructura familiar. Mediante proyecciones climáticas para los próximos 50 y 70 años, se han seleccionado áreas de acogida, tanto fuera como dentro de la distribución natural. Se ha plantado a la fecha un total de 5 ensayos de progenie y procedencia. De las 450 familias se seleccionaron aproximadamente 100 para análisis genómico. La migración asistida permitirá que se exprese la variación genética adaptativa y de esta forma salvaguardar el potencial evolutivo de esta especie. Provenance causes variation on early growth and survival and sun protection on physiological responses of the vulnerable Nothofagus glauca (Phil.) Krasser in a common garden in Central ChileArtículo de revistaWe assessed outplanting performance of N. glauca in two trials. In Trial 1, provenances from Pre- Andean (Linares, Longaví) and Coastal (Curanipe, Empedrado) origins were planted in a common garden under two sun protection treatments (i.e., black mesh shelter, and kaolin at 6% concentration), and a control treatment at full sun. In Trial 2, a local provenance was established under two site preparation treatments (i.e., old subsoiling from 4 years ago versus no-subsoiling). Growth, survival, gas exchange, and Chlorophyll fluorescence parameters were measured one year after outplanting. In Trial 1 survival was similar among treatments but larger seedlings were found under kaolin and in the local provenance Empedrado. The provenances varied by sun protection treatment in survival, and the Pre Andean provenance Linares tended to show the lowest survival at full sun. At the leaf-level physiology, provenances responded similarly in gas exchange and fluorescence parameters. In the sun protection treatments seedlings under kaolin increased stomatal conductance and electron transport, but decreased photosynthesis, water use efficiency, and efficiency of PSII. Provenances also varied by treatment in physiology. The Empedrado provenance exhibited the highest transpiration and stomatal conductance under kaolin whereas the Pre Andean provenance of Longaví showed the lowest photosynthesis and efficiency of PSII in the kaolin treatment. In Trial 2, root collar diameter, intercellular CO2 and water use efficiency were higher in the old-subsoiling treatment. As a potential adaptation tool, seed sources from Pre Andean origins can be established in Coastal origins with no detriments on seedling survival. La domesticación del maqui (Aristotelia chilensis): Un estudio de caso en ChileArtículo de revistaDebido a sus grandes beneficios nutricionales la demanda por productos de maqui ha aumentado considerablemente en la última década. Como dato ilustrativo, un estudio apoyado por FIA indica que la exportación de congelados y procesados de maqui ha crecido desde los US$ 1,18 millones en 2014 a los US$ 9,9 millones en 2016.