Alejandro Venegas-Gonzalez

Universidad Bernardo O'Higgins | UBO · ICA3

Payment for Ecosystem Services (PES) can promote different types of governance arrangements to address the triple challenge of biodiversity loss, climate change and air pollution. These institutional arrangements, however, do not explicitly incorporate climate change into the ecosystem’s capacity to provide services. In this study, we explore why a...

Globally, droughts are becoming longer, more frequent and more severe, and their impacts are multidimensional. The impacts of droughts typically extend beyond the water balance as they accumulate over time, and can lead to regime shifts in land use. Here, we assess the effects of temporal changes in water supply and demand on vegetation productivit...

Soil moisture (SM) is a crucial factor in the water cycle, sustaining ecosystems and influencing local climate patterns by regulating the energy balance between the soil and atmosphere. Due to the absence of long-term, in-situ measurements of SM, studies utilizing satellite-based data and tree-ring analysis have become valuable in assessing variati...

Background: The Altos de Cantillana mountain range (ACMR) in central Chile is composed of different vegetation communities, and is currently a priority site for conservation, due to its high endemism, high anthropogenic pressure and vulnerability to climate change. Research on biodiversity and carbon stocks in ACMR is essential to comprehend the re...

Background Treeline ecotones of Mediterranean ecoregions have been affected by the increasing intensity and severity of droughts. Even though the effect of droughts on forest dynamics has been widely documented, knowledge is relatively scarce of how extreme climate episodes affect the hydraulic structure and, therefore, the physiology of woody plan...

Las Soluciones de base Natural (SbN) permiten enfrentar desafíos y riesgos socioambientales mediante la protección, restauración y gestión sostenible de los ecosistemas, proporcionando bienestar humano e incrementando la biodiversidad. En la última década, la Ecorregión Mediterránea de Chile (EMC, 29-37ºS) ha experimentado una continua sequía y num...

Global climate change affects the natural dynamics of forests, with an increase in the intensity and duration of droughts in many regions, especially those with a Mediterranean climate. In these regions, the adaptive success of plants is related to annual xylem plasticity that affects hydraulic vulnerability, representing an important environmental...

It is widely accepted that global warming is affecting forests near the tree line by increasing tree growth in these cold-limited environments. However, since about 1970, a reduction in tree growth near the tree line has been observed in response to warming and increased drought stress. This reduction in tree growth has been mainly reported in fore...

Nothofagus alessandrii Espinosa is an endemic species of the coastal Maulino forest of central Chile that has historically been severely threatened by the reduction of its habitat and the isolation of its fragments. In addition, a gradual reduction in precipitation has been observed in recent years across its entire natural distribution area. Altho...

Introduction Presently, much of the sub-tropical environments around are rapidly changing due to direct human influences and recurrent droughts. Among them, the Mediterranean region of Chile (MC; 30 ° -37 ° S) in western South America is considered as part of the hotspot of earth biologically richest and most endangered terrestrial ecosystems (Mit...

The Mediterranean-type Ecosystems of Central Chile is one of the most threatened regions in South America by global change, particularly evidenced by the historical megadrought that has occurred in central Chile since 2010. The sclerophyllous forest stands out, whose history and relationship with drought conditions has been little studied. Cryptoca...

Interannual variability in the global land carbon sink is strongly related to variations in tropical temperature and rainfall. This association suggests an important role for moisture-driven fluctuations in tropical vegetation productivity, but empirical evidence to quantify the responsible ecological processes is missing. Such evidence can be obta...

Extreme drought events have increased in frequency during the 20th century triggered by global change. Thus, understanding tree-growth resilience across different terrestrial biomes has become a key goal in forest ecology. Here, we evaluate the tree-growth resilience to severe drought in the only Mediterranean-type Ecosystems of South America, usin...

Regional teleconnections permit cross-continental modeling of hydroclimate throughout the world. Tree-rings are a good hydroclimatic proxy used to reconstruct drought and streamflow in regions that respond to common global forcings. We used a multi-species dataset of 32 tree-ring width chronologies from Chile and Uruguay as a climate proxy to infer...

Los ecosistemas andinos de Chile central son una de las zonas más vulnerables al cambio climático a nivel mundial. Además, estos ecosistemas históricamente han sido usados por las comunidades locales para realizar ganadería trashumante en verano (veranadas). Sin embargo, los impactos de las veranadas en los ecosistemas de montaña, en un contexto de...

The current increase in deforestation rates of the Brazilian Amazon raises important questions about the resilience of trees in distinct vertical profiles in the world’s largest tropical rainforest. Seeking to prove the existence of temporal differences in tree growth response after forest fragmentation and edge effects through a dendrochronologica...

A fundamental pillar of community‐driven restoration projects is motivation, without which initiatives are doomed to fail. However, technical knowledge and funding are also important factors for success. In this work, we present three case studies of post‐fire restoration projects driven by local communities in Central Chile to assess whether motiv...

Soil moisture (SM) is a key variable in the earth surface dynamics; however, long-term in situ measurements at the global scale are scarce. In the Mediterranean Chilean Andes (MA; 30°-37°S), Sclerophyllous Forest tree species such as Belloto del Norte (BN; Beilschmiedia miersii) can grow for more than two centuries in very scarce humid lowland geog...

Global Climate Models project that observed climate trends are likely to be preserved and the number of extreme events will be increasing during the rest of the 21st century, which may have a detrimental impact on forest ecosystems. These impacts may include forest decline and widespread dieback of the most vulnerable biomes, such as the Mediterran...

Background and aims: The Mediterranean-type forest of central Chile is considered a "biodiversity hotspot" and a relic of a wider ancient distribution produced by past climatic oscillations. Nothofagus macrocarpa, commonly known as 'roble de Santiago', is a threatened palaeoendemism of this forest, poorly represented in the protected area system....

Lianas reduce tree growth, reproduction, and survival in tropical forests. Liana competition can be particularly intense in isolated forest fragments, where liana densities are high, and thus, host tree infestation is common. Furthermore, lianas appear to grow particularly well during seasonal drought, when they may compete particularly intensely w...

Since the year 2007, a megadrought has been affecting the water supply in Central Chile, reaching the year 2019 a critical condition. Currently, the information about how this drought is impacting vegetation productivity is scarce. This study aimed to analyze the vegetation productivity for season 2019-2020 by a remote sensing proxy which considere...

Edge effects are a major cause of natural dynamics of fragmented forests; however, studies that evaluate edge effects during the lifetime of trees are relatively rare. Through a long-term perspective of tree growth, dendroecology can contribute to a better understanding of the influence of edge effects. In order to frame our interpretation, we rais...

Edge effects are a major cause of natural dynamics of fragmented forests, however, studies that evaluate edge effects during the lifetime of trees are relatively rare. Through a long-term perspective of tree growth, dendroecology can contribute to a better understanding of the influence of edge effects. In order to frame our interpretation, we rais...

La zona de Chile central se ha visto afectada el último siglo por el calentamiento global. Sin embargo, aún es desconocido cómo los bosques de Nothofagus glauca (hualo) están respondiendo a los efectos de este fenómeno. El presente trabajo busca analizar la sensibilidad del crecimiento radial a la variabilidad climática local en dos poblaciones sep...

The Mediterranean forests in central Chile (MFCC) is one of the five biodiversity hotspots in South America. MFCC has experienced an uninterrupted sequence of dry years since 2010 with mean rainfall deficits of 20–40%. However, this region has suffered worse dry years than the current ones. The resilience of MFCC against the extreme drought years i...

Forests play an important role in water and carbon cycles in semiarid regions such as the Mediterranean ecosystems. Previous research in the Chilean Mediterranean forests revealed a break point in 1980 in regional tree-ring chronologies linked to climate change. However, it is still unclear which populations and age classes are more affected by rec...

Recent investigations indicate a warming of Atlantic Ocean surface waters since 1980, probably influenced by anthropic actions, inducing rainfall intensification mainly during the rainy season and slight reductions during the dry season in the Amazon. Under these climate changes, trees in upland forests (terra firme) could benefit from the intensif...

Background: Forest ecosystems are considered among the largest terrestrial carbon sinks. The dynamics of forest carbon depend on where the carbon is stored and its responses to environmental factors, as well as the physiology of the trees. Thus, threatened forest regions with high biodiversity have great scientific importance, such as the Sierra M...

Although the Amazon Forest comprises the world's largest rainforest, providing fundamental ecosystem services to human well-being, vicissitudes imposed by deforestation, climate change, widespread use of fire and development of new infrastructure make the region critically vulnerable to the consequences of the creation of new forest edges. In this...

Ongoing climate change is expected to alter forests by affecting forest productivity, with implications for the ecological functions of these systems. Despite its great dendrochronological potential, little research has been conducted into the use of wood density as a proxy for determining sensitivity to climate variability in Mexico. The response...

The Atlantic Forest is a Neotropical biome encompassing mainly Brazil's coastline and parts of Paraguay, Uruguay, and Argentina, but today surviving largely in small degraded patches and protected areas. Being a region under threat of extinction of its biological components, little is known about how climate change could influence the biodiversity,...

Global climate change will alter forests by shifting species ranges, which has implications for their ecological functions. Annual tree-ring widths and wood density are useful proxies for carbon cycle studies across a range of species. Here, using a dendroecological approach we sought to understand the carbon accumulation rates of two representativ...

An increase in drought conditions over the last century has been documented in Central Chile, a fact that could affect the Mediterranean forests, especially the northernmost Nothofagus populations from South America (Nothofagus macrocarpa). For this reason, it is key to study the climate influence on radial growth and trees establishment to design...

An emerging phenomenon of forest decline in Mediterranean-type ecosystems has been detected in response to climate change during the last century. It is expected that the Mediterranean regions will likely experience drought events during this century with consequences for biodiversity maintenance. Although the Chilean Mediterranean-type forests are...

An increase in drought conditions over the last century has been documented in Central Chile, a fact that could affect the Mediterranean forests, especially the northernmost Nothofagus populations from South America (Nothofagus macrocarpa). For this reason, it is key to study the climate influence on radial growth and trees establishment to design...

As análises de anéis de crescimento das árvores têm contribuído como uma importante ferramenta para a compreensão da ecologia das árvores, dinâmica florestal e das relações climáticas (dendroecologia). Esses dados contribuem para orientar práticas de manejo florestal, de conservação e de avaliação dos impactos das mudanças climáticas nos ecossistem...

La utilización de reguladores de crecimiento o fitorreguladores, es una alternativa para aumentar la floración en la familia Pinaceae. En este estudio se analizaron los efectos de la aplicación de reguladores de crecimiento (fitorreguladores) sobre brotes vegetativos y estróbilos masculinos de Pinus pinea L. Los productos seleccionados fueron: gibe...

In tropical forest, landscape fragmentation and the consequent degradation of disturbed forests increase the incidence of light and dry hot winds, causing a disturbance on natural regeneration. Under these conditions, lianas (woody vines) development is stimulated instead of other species, which are more suited to mature forest and under less influ...

Forest ecosystems play an important role in the global carbon cycle. Therefore, understanding the dynamics of carbon uptake in forest ecosystems is much needed. Pinus cooperi is a widely distributed species in the Sierra Madre Occidental in northern Mexico and future climatic variations could impact these ecosystems. Here, we analyze the variations...

Key message Analyses of tree-ring anatomical features showed to be more sensitive to specific intra-seasonal environmental factors than tree-ring width in Tectona grandis and Pinus caribaea growing in a subtropical region. Abstract Earlywood vessels (EWV) and intra-annual density fluctuations (IADFs) in tree rings are influenced by intra-seasona...

We explored the relationship between tree growth in two tropical species and local and large-scale climate variability in Southeastern Brazil. Tree ring width chronologies of Tectona grandis (teak) and Pinus caribaea (Caribbean pine) trees were compared with local (Water Requirement Satisfaction Index—WRSI, Standardized Precipitation Index—SPI, and...

The response functions are widely used in dendroclimatology to describe the relationship between climate and tree growth. In this study, Poincianella pluviosa var. peltophoroides (Fabaceae-Caesalpinaceae) and Bignonia pentaphylla (Bignoniaceae) trees were selected with the aim of evaluate the influence of air pollution by the application of tree-ri...

The aim of this study was to determine the influence of the length and diameter of apical vegetative shoots in female flowering and to verify polycyclic growth in a Pinus pinea plantation located in central Chile. The experiment was conducted in a plantation of 16 years six European origins, located in Casablanca district, Valparaíso Region. We ran...

The climate plays an important role in the formation of annual tree rings in the wood of forest species, as teak (Tectona grandis) and Caribbean pine (Pinus caribaea) used in ecological studies and climate reconstruction. This study aimed to determine the climatic influence of variables: cumulative rainfall, average temperature, drought indices (PD...

Tectona grandis L. (Verbenaceae) trees, teak, is used in dendrochronology studies in numerous regions, including Brazil. This study aimed to analyze the annual variation of the conductive elements of Tectona grandis trees through the area and numbers of vessels. The specific objectives are: (i) evaluate the lianas effect on vessels size in teak tre...

In Chile stone pine was introduced more than a century ago, mainly by Italian and Spanish immigrants who brought it as part of their culture; interest for this nut in Chile is recent and has been gradually increasing. Crown development is one of the most important factors on pine nut production because it is influenced mainly by light. In winter 20...

Climate plays an important role in annual tree-rings formation of several tree species, like Tectona grandis L., Verbenaceae (teak), commonly applied in dendroecological and dendroclimatological reconstructions. This study aimed to apply the tree-ring analysis to determinate the age and trunk growth rate of teak trees planted in two distinct sites...

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It presents grafting technique applied to pine nut (Pinus pinea L.) production, an alternative for temperate áreas, the case of Chile