Christian Salas-Eljatib

University of Chile · Departamento de Gestión Forestal y su Medio Ambiente

The global extent and distribution of forest trees is central to our understanding of the terrestrial biosphere. We provide the first spatially continuous map of forest tree density at a global scale. This map reveals that the global number of trees is approximately 3.04 trillion, an order of magnitude higher than the previous estimate. Of these tr...

Data from a 1 ha permanent sample plot in an old-growth Nothofagus obliqua dominated forest were used to study spatial patterns of dead and live trees using the Ripley’s K(t) function. Univariate and bivariate analyses were conducted. We computed confidence envelopes for a random (Poisson) spatial distribution using Monte Carlo simulations. An edge...

We present a linear model for the interacting effects of elevation, aspect, and slope for use in predicting forest productivity or species composition. The model formulation we propose integrates interactions of these three factors in a mathematical expression representing their combined effect in terms of a cosine function of aspect with a phase s...

We used stem-analysis data from 60 to 100 years-old second-growth stands, and single-point observations in 260–460 years-old trees, to study and model height development of Nothofagus obliqua (“roble”). The data covers a much wider range of ages than previous work on this species. A stochastic differential equation approach facilitated the estimati...

Accurate and cost-effective prediction of aboveground biomass (AGB), belowground biomass (BGB), and the total (ABGB) at stand-level within tropical forests is crucial for effective forest ecological management and the provision of forest ecosystem services. Although there has been research on simultaneously fitting biomass equations for tree compon...

La restauración de bosques requiere de una evaluación adecuada que permita establecer el nivel de éxito de ésta, así como también facilitar la toma de decisiones. Una apropiada evaluación, debería considerar el ajuste de modelos estadísticos con el fin de incorporar la incertidumbre en los análisis. El objetivo del presente capítulo es proveer el c...

The density of wood is a key indicator of the carbon investment strategies of trees, impacting productivity and carbon storage. Despite its importance, the global variation in wood density and its environmental controls remain poorly understood, preventing accurate predictions of global forest carbon stocks. Here we analyse information from 1.1 mil...

The emergence of alternative stable states in forest systems has significant implications for the functioning and structure of the terrestrial biosphere, yet empirical evidence remains scarce. Here, we combine global forest biodiversity observations and simulations to test for alternative stable states in the presence of evergreen and deciduous for...

The density of wood is a key indicator of trees’ carbon investment strategies, impacting productivity and carbon storage. Despite its importance, the global variation in wood density and its environmental controls remain poorly understood, preventing accurate predictions of global forest carbon stocks. Here, we analyze information from 1.1 million...

Aim To determine the relationships between the functional trait composition of forest communities and environmental gradients across scales and biomes and the role of species relative abundances in these relationships. Location Global. Time period Recent. Major taxa studied Trees. Methods We integrated species abundance records from worldw...

Una Revisión De Donoso Y Navarro (2023) Silvicultura Y Manejo De Bosques Nativos, ecología aplicada para la conservación de ecosistemas forestales. Editorial Universitaria. Santiago, Chile.

Forests are a substantial terrestrial carbon sink, but anthropogenic changes in land use and climate have considerably reduced the scale of this system¹. Remote-sensing estimates to quantify carbon losses from global forests2–5 are characterized by considerable uncertainty and we lack a comprehensive ground-sourced evaluation to benchmark these est...

Understanding what controls global leaf type variation in trees is crucial for comprehending their role in terrestrial ecosystems, including carbon, water and nutrient dynamics. Yet our understanding of the factors influencing forest leaf types remains incomplete, leaving us uncertain about the global proportions of needle-leaved, broadleaved, ever...

Determining the drivers of non-native plant invasions is critical for managing native ecosystems and limiting the spread of invasive species1,2. Tree invasions in particular have been relatively overlooked, even though they have the potential to transform ecosystems and economies3,4. Here, leveraging global tree databases5-7, we explore how the phy...

1. Biodiversity is an important component of natural ecosystems, with higher species richness often correlating with an increase in ecosystem productivity. Yet, this relationship varies substantially across environments, typically becoming less pronounced at high levels of species richness. However, species richness alone cannot reflect all importa...

Forest dynamics describe the change in structure and composition of forests over time, and is mainly driven by forest growth, a process resulting from size increase and mortality of trees, and recruitment of new individuals. An understanding of forest growth is essential for decision-making and research. An appropriate characterization of growth is...

Relative growth rates (RGR) have both intrigued and irritated many plant scientists since they were proposed as characteristics of growth performance in the early 20th century. Particularly, the common trend of RGR to decrease with increasing size, also referred to as ontogenetic drift, has given rise to many debates and much criticism. In this stu...

Spatial patterns reveal critical features at the individual and community levels. However, how to evaluate changes in spatial characteristics remains largely unexplored. We assess spatial changes in spatial point patterns by augmenting current statistical functions and indices. We fitted functions to describe unmarked and marked (tree size) spatial...

Climate is a critical variable in determining the productivity and structural complexity of forest ecosystems. Under similar temperature regimes and other site conditions, precipitation becomes fundamental for forest regeneration and growth, and eventually for the development of structural complexity and patterns in forest productivity. Empirical q...

Valdivian Temperate Rainforests in Chile have a global conservation value, but nowadays many correspond to secondary forests following regeneration in agricultural and burned lands, and to high-graded old-growth due to mismanagement, especially at mid to low elevations. Perspectives for increasing old-growth attributes in these productive forests t...

The latitudinal diversity gradient (LDG) is one of the most recognized global patterns of species richness exhibited across a wide range of taxa. Numerous hypotheses have been proposed in the past two centuries to explain LDG, but rigorous tests of the drivers of LDGs have been limited by a lack of high-quality global species richness data. Here we...

Background and aims Ulex europaeus L. (Fabaceae), commonly known as gorse, is an invasive woody shrub that easily grows in several locations across the world. However, little is known about the interactions of this invasive species with soil microorganisms and how these microbes can promote rapid grow-rates at early stages of development. We aim to...

One of the most fundamental questions in ecology is how many species inhabit the Earth. However, due to massive logistical and financial challenges and taxonomic difficulties connected to the species concept definition, the global numbers of species, including those of important and well-studied life forms such as trees, still remain largely unknow...

Significance Tree diversity is fundamental for forest ecosystem stability and services. However, because of limited available data, estimates of tree diversity at large geographic domains still rely heavily on published lists of species descriptions that are geographically uneven in coverage. These limitations have precluded efforts to generate a g...

Background: South America has the largest area of temperate forests in the Southern Hemisphere, which grow in diverse site conditions. The aim of this paper is to review the practices of silviculture applied and recommended for these temperate forests, and to discuss prospects to develop new silvicultural proposals to improve sustainability, adapta...

Purpose of Review Growth equations have been widely used in forest research, commonly to assess ecosystem-level behavior and forest management. Nevertheless, the large number of growth equations has obscured the growth-rate behavior of each of these equations and several different terms for referring to common phenomena. This review presents a unif...

El propósito de este libro es introducir al lector al mundo del software estadístico R. El análisis de datos y la construcción de modelos estadísticos son vitales en todas las disciplinas, desde la ingeniería, medicina, epidemiología, biología, genética, ecología, agronomía, hasta la economía y las políticas públicas. R es un software gratuito y d...

Background and aims Ulex europaeus L. (Fabaceae), commonly known as gorse, is an invasive woody shrub that easily grows in several locations across the world. However, little is known about the interactions of this invasive species with soil microorganisms and how these microbes can promote reaching rapid grow-rates at early stages of development....

Unique combinations of geographic and environmental conditions make quantifying the importance of factors that influence forest productivity difficult. I aimed to model the height growth of dominant Nothofagus alpina trees in temperate forests of Chile, as a proxy for forest productivity, by building a dynamic model that accounts for topography, ha...

Stem analysis allows us to obtain an abundant amount of information on tree growth. A couple of algorithms exist to utilize section height and growth ring data for reconstructing height and age time‐series information. I evaluated two alternatives, a well‐known and a newly proposed algorithm using stem analysis data of four species, including decid...

While the Chilean Society of Forest Sciences (SOCIFOR) was created by a group of forest-related institutions, its inactivity has wakened its progress. Here, we point out certain shortcomings of SOCIFOR, and propose actions to address them. We suggest increasing the number of members, restructuring its regulatory statutes-modeled on those used by ot...

Tree mortality is a critical ecological phenomenon shaping forest ecosystem dynamics, structure, and composition, while its effects are of global relevance due to its relationship with forest conditions and environmental changes. There are several challenges associated with individual-based mortality data, particularly observations with uneven meas...

Understanding the height growth of trees is a fundamental component for scientific knowledge and management of forest ecosystems. The height of dominant trees at a reference-age, commonly known as the site-index, is the most widely used forest productivity indicator globally. Yet, it has been criticized for its restricted applicability to monospeci...

Prumnopitys andina is a conifer tree species with a narrow distribution in Chile and Argentina. Despite its ecological importance, knowledge about the structure and dynamics of the forests where P. andina grows is limited. We aim to describe the structure and regeneration of forest with high presence of P. andina. Forests near Lonquimay (38°1' S, 7...

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Second-growth temperate forests usually have simpler composition and structure than comparable old-growth stands. We evaluated the application of variable density thinning (VDT) as a way to increase old-growth attributes, specifically tree species composition and density in two types of second-growth forests: a mixed evergreen-dominated forest (SE,...

Raulí (Nothofagus alpina (Poepp. & Endl.)) and Ulmo (Eucryphia cordifolia Cav.) are mid-tolerant tree species in the Coihue-Raulí-Tepa (ca. 0.55 mill ha) and Evergreen (ca. 4.1 mill ha) forest types in south-central Chile, respectively. These species have been selectively logged in old-growth forests especially during the 20th century, Raulí mostly...

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 previ...

Questions Fire is a key factor influencing Araucaria araucana forests, but the impact of fire severity on the understorey vegetation is not well understood. In this study we seek to answer the following questions: (a) how do initial plant diversity, composition and spatial distribution of the understorey vegetation change in response to different l...

Entendemos a la biodiversidad como la variedad de genes, especies y ecosistemas que se generan como resultado de los procesos evolutivos a lo largo del tiempo. Los cambios en procesos ambientales y climáticos asociados a la producción de biodiversidad han cobrado tal relevancia que la comunidad científica ha propuesto que hemos entrado en una nueva...

Este libro-manual desarrolla modelos de volumen para especies nativas del tipo forestal siempreverde en Chile. Los modelos de volumen propuestos son de tipo logarítmico, y emplean variables predictoras de fácil medición. No obstante, los de volumen de madera aserrada y de la copa requieren de variables de más compleja medición en terreno, i.e, altu...

2019, The Author(s), under exclusive licence to Springer Nature Limited. In this Letter, the middle initial of author G. J. Nabuurs was omitted, and he should have been associated with an additional affiliation: ‘Forest Ecology and Forest Management Group, Wageningen University and Research, Wageningen, The Netherlands’ (now added as affiliation 18...

A spatially explicit global map of tree symbioses with nitrogen-fixing bacteria and mycorrhizal fungi reveals that climate variables are the primary drivers of the distribution of different types of symbiosis.

Drimys winteri is an abundant tree species in the natural forests of Chile, growing as secondary forest of high ecological and economical importance between 41° and 43° S. The height-diameter relationship is key for estimating volume, biomass and for understanding ecological features of tree species. However, there is a lack of research about allom...

Rubus ulmifolius is a highly invasive species that negatively affects biodiversity, especially on Robinson Crusoe Island (RCI), one of the two global mini-hotspots of vascular plants. The rust Phragmidium violaceum has been used as a biological control agent for some Rubus species in mainland Chile, New Zealand and Australia. We aim to quantify P....

In the lowlands of south-central Chile, old-growth forests are scarce, whereas secondary forests are more frequent. The ecosystem services provided by these secondary forests differ from those associated with old-growth forests, reflecting their differences in composition and forest structure. Trees over 200 years-old, basal areas higher than 80 m2...

Self‐thinning and site maximum carrying capacity are key concepts for understanding and predicting ecosystem dynamics as they represent the outcome of several fundamental ecological processes (e.g., mortality and growth). Relationships are often derived using alternative modeling strategies, depending on the statistical approach, model formulation,...

Tree regeneration following even-aged silvicultural methods in the evergreen forest type (EFT) has been scarcely studied in Chile, although this is the largest forest type in a region of highly productive native forests. In 1981/ 1982 a total of nine 1.44-ha experimental units with old-growth forests of the EFT were subjected to block clearcutting...

In this analysis, a method for construction of forest canopy three-dimensional (3D) models from terrestrial LiDAR was used for assessing the influence of structural changes on reflectance for an even-aged forest in Belgium. The necessary data were extracted by the developed method, as well as it was registered the adjacent point-clouds, and the can...

Soil contains a wide variety of microorganisms that are responsible for fundamental ecological processes. However , increased frequency and severity of fires reduce microbial diversity and alter soil nutrient availability, affecting vegetation recovery. By using a large-scale wildfire that burned endangered Araucaria araucana forests in south-centr...

Growth is key for understanding forest stand dynamics, and is also important for sustainable forest management. Although individual tree growth is relatively easy to measure, forest growth can only be known by measuring stand variables (e. g. density, volume) on permanent sample plots over time. Due to costly maintenance of long term research progr...

Background: Invasion by exotic plants worldwide can lead to the loss of native species, particularly on islands with a high proportion of endemic plants, such as Robinson Crusoe Island (RCI). Aims: We studied the two most invasive exotic plant species occurring in the forest of RCI: Aristotelia chilensis and Rubus ulmifolius. We aimed at establishi...

El crecimiento de los bosques es clave para entender su dinámica y realizar un manejo sustentable. El crecimiento sólo se puede determinar al evaluar variables de estado (e.g., densidad y biomasa) a través unidades de muestreo permanentes (UMP) en el tiempo. Un monitoreo de las variables de estado es sólo posible de encontrar en un reducido número...

Binary variables have two possible outcomes: occurrence or non-occurrence of an event (usually with 1 and 0 values, respectively). Binary data are common in ecology, including studies of presence/absence, alive/dead, and change/no-change. Logistic regression analysis has been widely used to model binary response variables. Unbalanced data (i.e., an...

The landscape in the lowlands of south-central Chile is dominated by agricultural lands and forestry plantations of exotic species. Natural forests are restricted to successional forests, while old-growth forests are nearly absent. The lack of old-growth forests may deprive society from some ecosystem services. Both successional and old forests dif...

For carbon accounting or for developing REDD+ (Reducing Emissions from Deforestation and forest Degradation) programs, allometric equations for estimating both above-ground biomass (AGB) and below-ground biomass (BGB) are useful. We developed systems of weighted nonlinear allometric equations to estimate total, above- and below-ground biomass for D...