Forests Of Chile Research Articles

Spontaneous ignition of wildland fuel by idealized firebrands

The spontaneous ignition of a forest fuel layer by idealized firebrands was carried out experimentally in a bench scale apparatus designed to understand the relationship between the time to ignition and incident radiative heat flux on a ring-shaped forest fuel litter. Time to ignition, mass loss, radial temperatures and incident radiative heat flux were measured. The fuel samples were Radiata Pine needles, representative of Chilean forests and the influence of the physical characteristics of the fuel load were analyzed. The firebrand was idealized using a cylindrical electric heater capable of releasing heat flux up to 26.7 kW/m2. For the fuel beds considered the inverse of ignition time was found to be linearly dependent on the incident radiative heat flux, typically observed for thermally thin solid fuels. Several tests were carried out in order to estimate the critical (minimum) heat flux for spontaneous ignition for two forest fuel loads. Additionally, a quasi-linear relationship between mass loss rate and incident radiative heat flux was experimentally determined.

How competitive is the ‘pioneer-climax’ tree speciesNothofagus alpinain pristine temperate forests of Chile?

How competitive is the ‘pioneer-climax’ tree species<i>Nothofagus alpina</i>in pristine temperate forests of Chile?

Individual-Tree Diameter Growth Models for Mixed Nothofagus Second Growth Forests in Southern Chile

Second growth forests of Nothofagus obliqua (roble), N. alpina (raulí), and N. dombeyi (coihue), known locally as RORACO, are among the most important native mixed forests in Chile. To improve the sustainable management of these forests, managers need adequate information and models regarding not only existing forest conditions, but their future states with varying alternative silvicultural activities. In this study, an individual-tree diameter growth model was developed for the full geographical distribution of the RORACO forest type. This was achieved by fitting a complete model by comparing two variable selection procedures: cross-validation (CV), and least absolute shrinkage and selection operator (LASSO) regression. A small set of predictors successfully explained a large portion of the annual increment in diameter at breast height (DBH) growth, particularly variables associated with competition at both the tree- and stand-level. Goodness-of-fit statistics for this final model showed an empirical coefficient of correlation (R2emp) of 0.56, relative root mean square error of 44.49% and relative bias of −1.96% for annual DBH growth predictions, and R2emp of 0.98 and 0.97 for DBH projection at 6 and 12 years, respectively. This model constitutes a simple and useful tool to support management plans for these forest ecosystems.

Secondary Nothofagus dombeyi forests: site index curves and dominant height in the Coastal Range of south-central Chile

Nothofagus dombeyi is distributed on very diverse sites in the temperate forests of Chile and Argentina. In Chile, studies on its dynamics and productivity in forests, where it is the dominant species, have been carried out mainly in the foothills of the Andes, but the productivity and growth of these forests in the Coastal Range are almost unknown. The objective of this study was to evaluate the construction of a single dominant height/age growth model for two homogeneous edaphoclimatic zones (ZEH 2 and 5) previously defined for this species in the Coastal Range of south­central Chile. The results showed that the Chapman-Richards model was the best candidate function, in terms of goodness of fit and predictive capabilities. Using this function, specific parameters (a, b and c) were obtained for each zone, from which site models were constructed by the Algebraic Difference Approach method for a base age of 35 years. This model is intended to contribute to better estimations of site productivity for N. dombeyi forests in the Coastal Range of south-central Chile, and thus facilitate private and public decisions regarding their management.

Bringing ecosystem services into forest planning – Can we optimize the composition of Chilean forests based on expert knowledge?

In the following paper, we use robust optimization to calculate portfolios of Chilean forest stands which minimize the greatest underperformance among all considered ecosystem services (ES) and biodiversity. Forest experts were asked to score the six most important ES indicators and biodiversity for forest stands with either exotic or native tree species. Average scores and their variation were used to form an optimal forest portfolio (proportions of the five stand types). Quantitative indicators of ES were used to calculate the reference portfolio. Portfolios based on expert opinions (49% Eucalyptus plus Pinus, 51% native Nothofagus and mixed Pseudotsuga) did not differ significantly from portfolios based on quantitative indicators (51% Eucalyptus plus Pinus, 49% Nothofagus, mixed Pseudotsuga and Acacia). Both portfolios offer good protection against low achievement levels and prevent the degradation of important ES and biodiversity, while pure stands showed low achievement levels for specific ES. We conclude that integrating expert knowledge into forest planning may well support considering ES and biodiversity. Forest owners in the Mediterranean region of Chile should be encouraged to integrate native Nothofagus species into their forest portfolios to better provide for multiple ES and the conservation of biodiversity.

Vertical patterns of epiphytic bryophyte diversity in a montane Nothofagus forest in the Chilean Andes

ABSTRACTEpiphytic bryophytes are an important component of many forest ecosystems. Several studies have reported vertical distribution patterns for this species, finding many taxa growing along the entire vertical profile of host trees, some in the most exposed upper areas of the canopies. Many studies in Chilean forests have focused on epiphytes, but most of them were located in lowland and coastal forests. This study is the first scientific exploration of the epiphytic communities that occupy the entire vertical profile of large Nothofagus dombeyi (Mirb.) Oerst. trees in a montane Nothofagus forest in the Chilean Andes (39°25′S). Our goals were (i) to describe the richness of the epiphytic species inhabiting large N. dombeyi trees, (ii) to evaluate differences in composition related to the height, azimuth and diameter of each host tree, and (iii) to explore the distribution of epiphytic species within the vertical profile of trees. We climbed 10 large N. dombeyi trees located between 940 and 1190 m in altitude. All epiphytes were sampled every meter, from the base up to the highest climbable branch. The epiphytic community was dominated by non-vascular epiphytes, with 17 taxa, all of which were bryophytes. Frullania rostrata, Gackstroemia aff. magellanica, Hypnum skottsbergii and Zygodon penstastichus were the most frequently observed taxa. Species composition varied with height on the tree, but no differences between trees were observed. The vertical distribution showed that three taxa were restricted to the crown, five were abundant throughout the whole vertical profile and four were restricted to the trunk close to the ground. The information here could be relevant due to the pressure to manage these Nothofagus forests, where the associated biodiversity is not even recorded in forestry inventories.

Fleshy fruits as a lifebelt for seeds and the potential polychory of two wetland trees of temperate Chilean forests

The seeds of fleshy-fruited species growing in aquatic environments fall into water, with or without their pericarp depending upon whether gravity or animals disperse the seeds, with consequences little explored for seed ecology and dispersal in wetlands. In this study, we evaluated the germination of seeds with and without fleshy pericarp after water exposure (from 7 to 90 days), timing of fruit flotation and germination percentage from within intact fruits of two fleshy-fruited Myrtaceae trees of the Chilean temperate forests, Luma apiculata and Blepharocalyx cruckshanksii. For both species, we found greater germination in flooded seeds with pericarp than without, maximum fruit flotation for about a month, although buoyancy was reduced faster in B. cruckshanksii, and seedling emergence from inside fruits occurred in a grater percentage in B. cruckshanksii. These results show that the fleshy pericarp protects seeds from negative water effects, allowing hydrochory and it does not impede germination. Thus, there is a potential advantage for seeds being dispersed with their fleshy cover in wetland habitats. We assert that these species have multiple dispersal mechanisms (polychory) operating in wetlands, with consequences for their dispersal and recruitment.

Generalized allometric equations of total volume generated by meta-analysis for roble, raulí and coigüe in second growth forests in Chile

Generalized allometric equations of total volume generated by meta-analysis for roble, raulí and coigüe in second growth forests in Chile

New species and phylogenetic relationships of the spider genus Coptoprepes using morphological and sequence data (Araneae: Anyphaenidae).

We present evidence from the standard cytochrome c oxidase subunit I (COI) barcoding marker and from new collections, showing that the males and females of C. ecotono Werenkraut & Ramírez were mismatched, and describe the female of that species for the first time. An undescribed male from Chile is assigned to the new species Coptoprepes laudani, together with the female that was previously thought as C. ecotono. The matching of sexes is justified after a dual cladistics analysis of morphological and sequence data in combination. New locality data and barcoding sequences are provided for other species of Coptoprepes, all endemic of the temperate forests of Chile and adjacent Argentina. Although morphology and sequences are not conclusive on the relationships of Coptoprepes species, the sequence data suggests that the species without a retrolateral tibial apophysis may belong to an independent lineage.

How much water do Chilean forests use? A review of interception losses in forest plot studies

AbstractAfter several years of decreased annual rainfall and water shortages, the Chilean society is demanding that forest plantations take accountability of their role in consuming scarce water resources. Evidence has shown that interception losses are considerable when determining water production in watersheds. The aim of this study was to determine if site and stand variables explain interception losses by Chilean forests for the development of an empirical model that could predict the potential impacts of forest management practices and land‐use change. A total of 127 data from annual water balance plot studies in Chile were compiled to derive relationships between interception and precipitation, species composition, plantation age and other stand and site variables. The reviewed data indicated that annual interception losses are mainly explained by annual rainfall and basal area of the forest stands, with a clear difference between the northern (dryer) and southern (wetter) regions of Chile. For a wide latitudinal gradient, forest composition and age, annual interception accounted for approximately 21% of incoming precipitations. Broadleaved forest stands (including native broadleaved and eucalypt forests) generally presented higher interception losses than conifers. Interception was higher in northern zones, indicating that forests have greater impacts on water resources in dryer regions. Our results were compiled in empirical models, which can be used to estimate forest interception in a latitudinal gradient in Chile and to support policy making. These results are also proposed as an approximate analogue of the changes in forest interception losses, which may occur as vegetation belts shift latitudinally as a result of the impact of climate change. Copyright © 2016 John Wiley &amp; Sons, Ltd.

Assessing the completeness of inventories of vascular epiphytes and climbing plants in Chilean swamp forest remnants

ABSTRACTPlant species inventories provide the foundation for more complex analytical studies and are the basis of monitoring programmes; however, if they are to provide reliable information in the long term, their level of completeness needs to be estimated. This work assessed the completeness of inventories of climbing plants and vascular epiphytes in swamp forest remnants of the Araucanía region of south-central Chile, which has been severely disturbed by agroforestry expansion. We sampled 30 sites using transects, with observations from ground level to a height of 2.3 m up the trees. To assess the potential existence of unrecorded species we drew rarefaction curves based on sample trees and extrapolated them towards one of the most intensely sampled sites. We then calculated the asymptotic species richness with the Chao 1 estimator. The results showed: (1) a total richness of 16 species of epiphytes and 17 species of climbing plants; (2) the rarefaction curve differentiated only two categories of sampling effort (‘rich’ and ‘poor’ sites) as a result of the substantial overlap of the confidence limits at 95%; and (3) the maximum richness estimated by Chao 1 was similar to the richness observed in all the sites. We conclude that greater sampling effort is required to obtain tighter statistical confidence levels in the rarefaction curve; however, from a biological point of view, the sampling effort achieved adequate representation of the species richness at all the sites. Total richness of vascular epiphytes and climbing plants was only slightly below values reported for much larger areas of better-conserved forest in south-central Chile and adjacent areas of Argentina. Finally, we found evidence that forest fragmentation has more severe effects on species richness of vascular epiphytes than on that of climbing plants.

Fragmentation of Araucaria araucana forests in Chile: quantification and correlation with structural variables

Abstract: Landscape fragmentation is one of the main threats to South American temperate forests due to population growth, conversion of native forests to plantations of exotic species and non-sustainable timber harvesting. The lack of forest connectivity can interfere with pollination, seed dispersal, biodiversity and landscape quality. Species with relatively limited seed dispersal are potentially more sensitive to the landscape fragmentation. Araucaria araucana (Mol.) K. Koch is a long-lived, slow-growing, relict conifer in South America’s temperate forests with large seeds possessing a limited dispersal range. The objective of the study was to identify priority areas for Araucaria conservation based on fragmentation quantification and correlation with structural variables and regeneration conditions. Results from the FRAGSTATS® and CONEFOR® software indicated that Araucaria connectivity has increased in sites located in the central Andean Range in comparison to other sites, because of reduced human and livestock pressure as well as the relative absence of commercial plantations. The proximity index ranged from 6.01 m to 34834.2 m, and the probability of connectivity has significantly increased (175663 ha) in the central Andean Range. Significant relationships were found between the Simpson’s index (or the probability of connectivity) and basal area, and between the mean largest patch index and crown diameter. The largest patch index (r = 0.6; p < 0.05) and the area-weighted mean proximity index (r = 0.767; p < 0.05) were the most important landscape metrics influencing Araucaria regeneration. Furthermore, the integration of spatial pattern analysis obtained from satellite images and aerial photographs with forest and regeneration characterization from field sampling allowed to identify the most vulnerable areas. The methodology presented here can assist in the identification of target areas for spatial conservation, including management needs under the current budget restrictions.

Composition patterns and network structure of epiphyte–host interactions in Chilean and New Zealand temperate forests

ABSTRACTEcological networks are becoming increasingly used as a framework to study epiphyte–host interactions. However, efforts to quantify the properties of epiphyte–host networks have produced inconsistent results. Epiphyte–host interactions in New Zealand and Chilean temperate forests were quantified to test for non-random patterns in nestedness, negative co-occurrences, number of links, and network specialisation. Results showed that three out of five New Zealand networks were significantly more nested than null model expectations, compared with just one out of four Chilean networks. Epiphytes co-occurred more often than null model expectations in one New Zealand network and one in Chile. In all cases, the number of links maintained by each epiphyte and host species was consistent with null model expectations. Lastly, two New Zealand networks and one in southern Chile were significantly less specialised than null model expectations, with all remaining networks returning low specialisation scores. As such, aside from the tendency for greater nestedness in New Zealand networks, most epiphyte species were distributed on their host trees at random. We attribute the result of nestedness in New Zealand to the abundance of large nest epiphytes (Astelia spp. in particular), which may facilitate the sequential colonisation of epiphyte species on developing host trees. The lack of negative co-occurrences suggests that negative species interactions are not an important determinant of species assemblage structure. Low network specialisation scores suggest that epiphytes are selecting for specific host traits, rather than specific host species for colonisation.

Impacts of nonstate, market-driven governance on Chilean forests

Global markets for agricultural products, timber, and minerals are critically important drivers of deforestation. The supply chains driving land use change may also provide opportunities to halt deforestation. Market campaigns, moratoria, and certification schemes have been promoted as powerful tools to achieve conservation goals. Despite their promise, there have been few opportunities to rigorously quantify the ability of these nonstate, market-driven (NSMD) governance regimes to deliver conservation outcomes. This study analyzes the impacts of three NSMD governance systems that sought to end the conversion of natural forests to plantations in Chile at the start of the 21st century. Using a multilevel, panel dataset of land use changes in Chile, we identify the impact of participation within each of the governance regimes by implementing a series of matched difference-in-differences analyses. Taking advantage of the mosaic of different NSMD regimes adopted in Chile, we explore the relative effectiveness of different policies. NSMD governance regimes reduced deforestation on participating properties by 2-23%. The NSMD governance regimes we studied included collaborative and confrontational strategies between environmental and industry stakeholders. We find that the more collaborative governance systems studied achieved better environmental performance than more confrontational approaches. Whereas many government conservation programs have targeted regions with little likelihood of conversion, we demonstrate that NSMD governance has the potential to alter behavior on high-deforestation properties.

Patterns of carbon storage in relation to shade tolerance in southern South American species.

Carbon (C) allocation to storage in woody tissues at the expense of growth is thought to promote shade tolerance, yet few studies on the subject examined C storage during maximum growth and considered stand influences. I asked how C storage in different plant tissues relates to shade tolerance in temperate forests with contrasting climates and physiognomies, and whether relationships vary during the growing season. In the late spring and late summer, I harvested seedlings of eight species with contrasting light requirements from the understory of a cold rainforest and a Mediterranean forest in Chile. Nonstructural carbohydrate (NSC) concentrations and pools (i.e., biomass x NSC concentration) were determined in leaves, aboveground wood, and roots. The effects of shade tolerance and sampling date on the NSCs were analyzed for each forest and tissue with linear mixed-effects models. In both forests, concentrations of NSC and soluble sugars in woody tissues, as well as fractions of NSC in these tissues, were lower in shade tolerant than in shade intolerant species. For root NSC concentrations, these trends depended on the sampling date: in the late spring the concentrations were similar in shade tolerant and intolerant species, while in the late summer they were lower in shade tolerant species. Shade tolerance is not linked to C storage in the two studied forests, suggesting that allocation to growth or defenses could be more advantageous for low light persistence. Alternatively, high levels of C storage could be also selected in shade intolerant species to face herbivory or drought.

A revision and phylogenetic analysis of the spider genus Oxysoma Nicolet(Araneae: Anyphaenidae, Amaurobioidinae).

We review the spider genus Oxysoma Nicolet, with most of its species endemic from the southern temperate forests in Chile and Argentina, and present a phylogenetic analysis including seven species, of which three are newly described in this study (O. macrocuspis new species, O. kuni new species, and O. losruiles new species, all from Chile), together with other 107 representatives of Anyphaenidae. New geographical records and distribution maps are provided for all species, with illustrations and reviewed diagnoses for the genus and the four previously known species (O. punctatum Nicolet, O. saccatum (Tullgren), O. longiventre (Nicolet) and O. itambezinho Ramírez). The phylogenetic analysis using cladistic methods is based on 264 previously defined characters plus one character that arises from this study. The three new species are closely related with Oxysoma longiventre, and this four species compose what we define as the Oxysoma longiventre species group. The phylogenetic analysis did not retrieve the monophyly of Oxysoma, which should be reevaluated in the future, together with the genus Tasata.

Effects of riparian forest management on Chilean mountain in-stream characteristics

We assessed the effect of forest management practices on temporal differences in riparian litterfall input and autumnal leaf litter processing of 3 evergreen plant species, using independently 2 mesh sizes (for two of the three species), between two contrasting headwater streams draining (a) near-pristine and (b) harvested evergreen old-growth forests in Chile (39°S). Additionally, we compared rainfall, streamflow, suspended sediment concentration, and the in-stream invertebrate community, collected two years after logging in the harvested microcatchment. The harvested forested stream had higher runoff, suspended sediment concentration and input of litter (3377kgha−1yr−1) than the pristine stream (3166kgha−1yr−1). However, leaf-litter decay rates were faster for the pristine (ranging from k=−0.0120 to −0.0024day−1) than for the harvested forest stream (k=−0.0049 to −0.0023day−1) depending on leaf species and litterbag type. Likewise, the pristine stream revealed higher shredder taxa richness than harvested stream, suggesting a higher correlation with the decomposition rate and leaf mass losses. Therefore, the results of our study suggest that despite the implementation of best management practices on riparian forests, there are detectable shifts in the structure and functioning of aquatic invertebrate community in the Andean streams of south-central Chile.

A mixed integer programming model to evaluate integrating strategies in the forest value chain — a case study in the Chilean forest industry

When a company is integrated vertically, it can manage and plan its overall value chain in one direct and integrated approach. However in many cases, companies follow a decoupled approach where forests and production plants optimize separately their processes in a supply-driven strategy. In Chile, the two largest forest companies are vertically integrated (i.e., they own forest and mills that produce logs, lumber, plywood, pulp, paper, and bioenergy, etc.). Historically, they have coordinated their value chains using a make-to-stock strategy, for which the forest is the main driver of the value chain activities. In this paper, we propose an integrated planning approach to show the impacts of a demand-driven integration of the value chain in the forest industry. To compare this strategy with the decoupled strategy, we propose a mixed integer programming (MIP) model for the integrated strategy. To illustrate our proposal, we use forest and production information from a Chilean forest company. The decoupled strategy, where the forest and industry planning are planned separately, uses two models. The first model deals with the forest management and harvesting decisions and maximizes the expected net present value (NPV) of logs. In this model, the planning horizon covers one full forest rotation, which in Chile corresponds to about 25 years. The second model maximizes the NPV of the downstream operations for a shorter business planning horizon (five years) constrained by the availability of the logs from the first model. In the integrated approach, all parts of the value chain (forest, transportation, and mills) are driven by final product demand and where the objective is to maximize the profit of the company (NPV of the entire value chain). The demand is only given for the shorter business planning horizon. The two strategies are evaluated using the MIP model, and NPV is used to determine the best practice. According to the results, the NPV can increase up to 5.0% when the proposed integrated strategy is implemented compared to a decoupled strategy. Moreover, the profit for the business period increases up to 8.5%.

Use of tree species by White-throated treerunner (Pygarrhichas albogularis King) in a secondary native forest of southern Chile

ABSTRACT In forest ecosystems, numerous species of insectivorous birds use certain tree species as feeding and nesting substrates. Between 2009 and 2010, the use of different floristic components as feeding substrate by the Pygarrhichas albogularis King, 1831 was evaluated in a southern Chilean secondary native forest. From a total of 13 trees and bush species, six tree species were used by P. albogularis as a feeding substrate. Tree use was limited to intermediate heights (11-20 m) and, mainly, to the trunk (40% of observations) and secondary branches (26%). Pygarrhichas albogularis showed a disproportionated use of N. dombeyi and an important use of trees with a greater age structure (DBH 81-100 cm). Nothofagus dombeyi presented a significantly greater tree bark crevice depth than E. cordifolia. In turn, covariance between crevice depth and invertebrate supply in tree bark was positive and significant. We consider bark depth and invertebrate supply to be the proximate causes explaining P. albogularis disproportionated use of Nothofagus dombeyi.

Extracellular Biosynthesis of Copper and Copper Oxide Nanoparticles by Stereum hirsutum, a Native White‐Rot Fungus from Chilean Forests

The white‐rot fungus Stereum hirsutum was studied to evaluate its applicability for use in the biosynthesis of copper/copper oxide nanoparticles under different pH conditions and in the presence of three different copper salts (CuCl2, CuSO4, and Cu(NO3)2). The nanoparticle formation was evaluated by UV‐visible spectroscopy, electron microscopy (TEM), X‐ray diffraction analysis (XRD), and Fourier transforms infrared spectroscopy (FTIR). The nanoparticles biosynthesis in presence of all copper salts demonstrated higher formation with 5 mM CuCl2 under alkaline conditions. TEM analysis confirmed that the nanoparticles were mainly spherical (5 to 20 nm). The presence of amine groups attached to nanoparticles was confirmed by FTIR, which suggests that extracellular protein of fungus is responsible for the formation of the nanoparticles. Therefore, the white‐rot fungus S. hirsutum was found to exhibit potential for use in the synthesis of copper/copper oxide nanoparticles.