Amico I.,Instituto Nacional de Tecnologia Agropecuaria |
Bava J.,Research Center y Extension Forestal Andino Patagonico |
Bava J.,National University of Patagonia San Juan Bosco |
Calderon A.D.,Instituto Forestal
Revista de la Facultad de Ciencias Agrarias | Year: 2010
In the northwest of Chubut poplars are established as lines for wind break in grazing land protection or where they are grown non-irrigated hay. Populus nigra 'Italica' is the most widespread clone in linear plantations, located in different site qualities. There is no background on height growth and Site Index in the area. Eight sites were selected for sampling where 24 dominant trees were felled for stem analysis. With the database of age-height resulting from stem analysis of sample trees, we ajusted the Chapman-Richard's model, using nonlinear regression techniques. We built a family of height growth curves using the guide curve methodology. Site Index curves, based on height and age, were constructed by mathematical deduction of height growth function, taking as reference age 25 years at breast height. We defined five site qualities, With a range of 4 meters, With site index from 19 to 35 m.
Reyes R.,Instituto Forestal |
Reyes R.,University of British Columbia |
Nelson H.,University of British Columbia |
Navarro F.,Clean Energy Consultant |
Retes C.,Clean Energy Consultant
Energy for Sustainable Development | Year: 2015
The mitigation of climate change requires developing alternatives to fossil fuels, while simultaneously looking for ways to increase the resilience of our socioecological systems especially those reliant on ecosystem goods and services. Forest biomass is receiving increased attention as a source of renewable fuel; yet at the same time, increased use of wood fuels raises health concerns about the adverse effects of pollution and as a possible contributor to deforestation and forest degradation. For these reasons, where people use wood fuel, policies are designed to shift people away from wood fuel and using forest biomass and up the energy ladder, typically toward fossil fuels. Using a case study from Chile, where air pollution from residential firewood combustion has become a serious issue, we show that while such policies might reduce pollution in the short term, they are unlikely to improve either human well-being or the sustainability of resource use in the long term. Instead of policies designed to reduce or eliminate wood fuel use, by examining the interlinked energy and resource subsystems and socioeconomic context within which wood fuel is used, we argue that a combination of policy interventions targeting the adoption of energy-saving technologies, while still maintaining wood fuel as a primary energy source, would yield higher economic, social, and environmental benefits. © 2015 International Energy Initiative.
Valencia J.,Instituto Forestal |
Harwood C.,CSIRO |
Washusen R.,CSIRO |
Morrow A.,CSIRO |
And 2 more authors.
Wood Science and Technology | Year: 2011
Peripheral longitudinal growth strain (LGS) was measured on a total of 81, 22-year-old pruned Eucalyptus nitens trees from five thinning treatments in a plantation thinning trial in Tasmania. Growth strain data were gathered at breast height on each tree using the CIRAD-Forêt method. The effects of thinning treatment and tree diameter on LGS and its relationships to solid-wood traits determined in a processing trial were examined. LGS was significantly higher in the direction of the prevailing wind and was not significantly affected by either thinning treatment or tree diameter. An index of log end splitting was positively related to tree diameter, sawlog position (upper/lower), and LGS, which explained up to an additional 20% of the variance after tree diameter and log position were accounted for in a linear regression model. High LGS and log end splitting were significant indicators of increased board end splitting. © 2010 Springer-Verlag.
Hildebrandt P.,TU Munich |
Kirchlechner P.,TU Munich |
Hahn A.,TU Munich |
Knoke T.,TU Munich |
Mujica H. R.,Instituto Forestal
European Journal of Forest Research | Year: 2010
Financial assessment in forestry is characterized by considerable impacts of risk factors due to large time horizons. Accounting for the risk of timber price fluctuation mixtures of Rauli (Nothofagus alpina, P. et E., OERST.) and Douglas fir (Pseudotsuga menziesii, Mirb.) have been evaluated by different approaches. The data were taken from plantations in Southern Chile between 39°10′ and 39°50′ south latitude. Increments have been modelled in order to calculate possible financial returns and changed volume growth has been taken into consideration for mixtures of large blocks and single-tree mixtures of both species. The optimum proportions of both species varied depending on the different perspectives of the financial assessment: first, the effects of diversification shown by classical portfolio approach were low; second, the integration of moderate risk aversion of the decision maker resulted in predominance of stands with high proportions of Douglas fir, but optimum proportions of Rauli increased with higher degrees of risk aversion. The maximization of the expected surplus in relation to the fluctuation of net present values (NPVs) (Sharpe ratio) resulted in even higher optimum proportions of Rauli. However, mixed stands proved more advantageous in contrast to the financial assessment without consideration of the risk factor timber price fluctuation (maximization of NPV). Finally, the integration of further risk factors can have impacts on the results as well as the integration of further effects of single-tree mixtures. Both lacks of information should be investigated for more extensive assessments in the future. © 2009 Springer-Verlag.
Ballesta P.,University of Concepcion |
Mora F.,University of Talca |
Contreras-Soto R.,University of Concepcion |
Ruiz E.,University of Concepcion |
Perret S.,Instituto Forestal
Acta Scientiarum - Technology | Year: 2015
Eucalyptus cladocalyx F. Muell is a tree endemic to southern Australia and is distributed across four isolated regions: Kangaroo Island, southern Flinders Ranges, and two geographical zones in Eyre Peninsula. E. cladocalyx is capable of growing under extreme environmental conditions, including dry and saline soils. The objective of this study was to analyze genetic diversity in 45 half-sib families planted in northern Chile that are distributed across five different zones (provenances). Genetic variability was assessed using ISSR (Inter Simple Sequence Repeat) molecular markers. The results showed low levels of genetic diversity within populations (He = 0.113 to 0.268) in contrast with other Eucalyptus species. In addition, there was a significant genetic differentiation among provenances (Φst = 0.14); populations from the Kangaroo Island provenance showed more differentiation than any other population. These results are in agreement with previous studies of the species. Our study revealed that Chilean resources are a representative sample of Australian populations; therefore, the germplasm planted in northern Chile would be sufficient for the development of improvement programs. ISSR-Marker technology could be an alternative to identify genotypes of interest in material selection. © 2015, Eduem - Editora da Universidade Estadual de Maringa. All rights reserved.