Aitor Ameztegui

University of Lleida | UDL · Department of Agricultural and Forest Sciences and Engineering

Aim To assess the effects of climate change, past land uses and physiography on the current position of the tree line in the C atalan P yrenees and its dynamics between 1956 and 2006. Location More than 1000 linear kilometres of sub‐alpine tree line in the C atalan P yrenees (north‐east S pain) Methods Using aerial photographs and supervised clas...

Mediterranean forests play a key role in providing services and goods to society, and are currently threatened by global change. We assessed the future provision of ecosystem services by Mediterranean pine forests under a set of management and climate change scenarios, built by combining different regional policies and climate change assumptions. W...

Canopy height is an excellent indicator of forest productivity, biodiversity and other ecosystem functions. Yet, we know little about how elevation drives canopy height in mountain areas. Here we take advantage of an ambitious airborne LiDAR flight plan to assess the relationship between elevation and maximum forest canopy height, and discuss its i...

Forests provide a wide range of provisioning, regulating and cultural services of great value to societies across the Mediterranean basin. In this study, we reviewed the scientific literature of the last 30 years to quantify the magnitude of projected changes in ecosystem services provision by Mediterranean forests under IPCC climate change scenari...

Mountain regions in Western Europe have gone through a massive rural–urban migration and the collapse of their traditional socioeconomic system. As a result, forest has occupied many old pastures and croplands. In protected areas – such as National Parks – changes in the landscape can affect biodiversity and other services, including the values tha...

Mountain forests face important threats from global change and spatio-temporal variation in tree height can help to monitor these effects. In this study, we used the Global Ecosystem Dynamics Investigation space-borne laser sensor to examine the relationship between maximum tree height and elevation, and the role of climate, in the main European mo...

Tree growth is a key uncertainty in projections of forest productivity and the global carbon cycle. While global vegetation models commonly represent tree growth as a carbon assimilation (source)-driven process, accumulating evidence points toward widespread non-photosynthetic (sink) limitations. Notably, growth biophysical potential, defined as th...

Biotic and abiotic conditions have been found to strongly influence how biodiversity affects ecosystem functioning in forests. This context dependency of biodiversity‐productivity relationships in real‐world ecosystems may be shaped by the biogeographic context via deep‐time processes acting on the size and composition of the species pool such as d...

Background Climate change is altering the fire regime and compromising the post-fire recovery of vegetation worldwide. To understand the factors influencing post-fire vegetation cover restoration, we calculated the recovery of vegetation in 200,000 hectares of western Mediterranean forest burned by 268 wildfires over a 27-year period (1988–2015). W...

Little is known about the growth interactions of black spruce (Picea mariana) and tamarack (Larix laricina), two important commercial tree species of the Canadian boreal forest. We investigated growth relations between black spruce and tamarack in mature mixed stands. We sampled tree-rings of 223 black spruce and 103 tamaracks to analyze their basa...

Aim: Growing evidence suggests that impacts of biodiversity loss on ecosystem functioning and nature's contributions to people are usually negative, yet the magnitude and direction of these impacts can be variable across naturally-assembled ecosystems. A potential driver of variation in diversity-productivity relationships is the biogeographical co...

Mountain forests face significant threats from global change and spatio-temporal variation in tree height can help to monitor these effects. While tree height is typically measured through field inventories, remote sensing can provide accurate and extensive forest structure data. In this study, we used the Global Ecosystem Dynamics Investigation sp...

Regional-level applications of dynamic vegetation models are challenging because they need to accommodate the variation in plant functional diversity, which requires moving away from broadly defined functional types. Different approaches have been adopted in the last years to incorporate a trait-based perspective into modeling exercises. A common p...

Forests are exposed to changing climatic conditions reflected by increasing drought and heat waves that increase the risk of wildfire ignition and spread. Climatic variables such as rain and wind as well as vegetation structure, land configuration and forest management practices are all factors that determine the burning potential of wildfires. The...

Thinnings are silvicultural operations that repetitively reduce tree density to improve the vigour of the remaining trees and the economic benefits of the stands. Thinning can also enhance the provision of various ecosystem services throughout the rotation period. In this study, we use a modelling approach to evaluate stand dynamics and the provisi...

Wood formation during the growing season is shaped by the intra-annual variability of climatic conditions. In the Mediterranean, the cambial activity is seasonally constrained by winter low temperature and summer drought, resulting in bimodal growth patterns. Although bimodal growth is an ecologically important adaptation of woody species to season...

Regional-level applications of dynamic vegetation models are challenging because they need to accommodate the variation in plant functional diversity, which requires moving away from broadly-defined functional types. Different approaches have been adopted in the last years to incorporate a trait-based perspective into modeling exercises. A common p...

Mediterranean forests and fire regimes are closely intertwined. Global change is likely to alter both forest dynamics and wildfire activity, ultimately threatening the provision of ecosystem services and posing greater risks to society. In this paper we evaluate future wildfire behavior by coupling climate projections with simulation models of fore...

In Spain, 55% of land area is covered by forests and other woodlands. Broadleaves occupy a predominant position (56%), followed by conifers (37%) and mixed stands (7%). Forest are distributed among the Atlantic (northwestern Iberian rim), Mediterranean (rest of the peninsula including the Balearic Islands) and Macaronesian (Canary Islands) climate...

El proyecto LIFE ADAPT-ALEPPO (2021-2025), tiene como principal objetivo el desarrollo de nuevas herramientas para la adaptación de los bosques ibéricos de pino carrasco (subtipo 42.841 del Hábitat 9540 de la Directiva Hábitats, Anexo I) al cambio climático, así como su aplicación demostrativa. Estas herramientas se centrarán en la detección tempra...

Thinnings are silvicultural operations that repetitively reduce tree density to improve the ecological, economic, and social benefits of the stands. Thus, the correct choice of the thinning regime can enhance stand structure and the provision of various ecosystem services throughout the rotation period. In this study, we use a modelling approach to...

Biomass and carbon content are essential indicators for monitoring forest ecosystems and their role in climate action, but their estimation is not straightforward. A typical approach to solve these limitations has been the estimation of tree or stand biomass based on forest inventory data, using either allometric equations or biomass expansion fact...

Many mountain regions in Europe have experienced massive migrations towards metropolitan areas, with far-reaching implications for societies and the environment, especially croplands and grasslands. In this work, we tailored a geospatial framework to envisage the probability of land abandonment in the Spanish Pyrenees at moderate spatial resolution...

En aquest document s'estableix una metodologia per calcular l'impacte de la gestió forestal multifuncional en tres factors clau de la mitigació i l'adaptació al canvi climàtic a la Mediterrània: el carboni, l'aigua i la biodiversitat. En aquesta primera versió, l'impacte de la gestió en el balanç de carboni s'ha obtingut per a les principals conífe...

Just as the aboveground tree organs represent the interface between trees and the atmosphere, roots act as the interface between trees and the soil. In this function, roots take-up water and nutrients, facilitate interactions with soil microflora, anchor trees, and also contribute to the gross primary production of forests. However, in comparison t...

Plant diversity is a core value of forests and is rapidly becoming a primary management goal under the threat of global environmental changes. Changing conditions, including forestry interventions, or lack of them, may endanger its preservation. Abandonment of management in forests previously subjected to a multipurpose silviculture and secondary s...

Despite the need for preserving the carbon pools in fire-prone southern European landscapes, emission reductions from wildfire risk mitigation are still poorly understood. In this study, we estimated expected carbon emissions and carbon credits from fuel management projects ongoing in Catalonia (Spain). The planning areas encompass about 1000 km 2...

Pine species are dominant in a large part of the western Mediterranean landscapes where they provide a wide range of goods and services. At present, the different components of global change threaten the delicate equilibrium between the current structure and functioning of most of these pinewoods and the future provision of ecosystem services requi...

Secondary succession (SS) is one of the main consequences of the abandonment of agricultural and forestry practices in rural areas, causing -among other processes- woody encroachment on former pastures and croplands. In this study we model and monitor the spatial evolution of SS over semi-natural grassland communities in the mountain range of the P...

Marine ecosystems: Despite covering only 0.82% of the ocean’s surface, the Mediterranean Sea supports up to 18% of all known marine species, with 21% being listed as vulnerable and 11% as endangered. The accelerated spread of tropical non-indigenous species is leading to the “tropicalization” of Mediterranean fauna and flora as a result of warming...

Wildfires in the Mediterranean are strongly tied to human activities. Given their particular link with humans, which act as both initiators and suppressors, wildfire hazard is highly sensitive to socioeconomic changes and patterns. Many researchers have prompted the perils of sustaining the current management policy, the so-called ‘total fire exclu...

RESUMEN En las últimas décadas, los bosques de montaña europeos han sufrido las consecuencias del abandono de las actividades agrosilvopastorales tradicionales bajo la forma de una importante expansión y densificación del monte. En este trabajo, se ha evaluado la importancia de ambos procesos y las derivaciones a nivel de la configuración del paisa...

Aim Niche‐based models often ignore spatial variation in the climatic niche of a species across its occupied range and the related variation in the response to changing climate conditions. This assumption may lead to inaccurate predictions of species distribution shifts under climate change. Models have been developed to address this issue, but mos...

Understanding and measuring forest resistance and resilience have emerged as key priorities in ecology and management, particularly to maintain forest functioning. The analysis of the factors involved in a forest’s ability to cope with disturbances is key in identifying forest vulnerability to environmental change. In this study, we apply a procedu...

The poster presents foreMA-DST, a Decision Support Tool aiming at facilitating multi-objective forest planning under climate change uncertainties, by integrating state of the art scientific knowledge into a management-oriented user interface.

Understanding ecosystem vulnerability is essential in risk management to anticipate disasters. While valuable efforts have been made to characterize vulnerability components (exposure, sensitivity, and response capacity) at particular ecosystem stages, there is still a lack of context-specific studies accounting for the temporal dimension of vulner...

Key message Elevation markedly modified the species-specific phenotypic responses of trees to light. The effects from elevation mostly occurred at organ level (SLA) for the montane species, but at whole-plant level (allocation traits) for the subalpine ones. The subalpine species allocate more carbon to roots under closed canopies at low elevation....

In the climate change era, forest managers are challenged to use innovative tools to encourage a sustained provision of goods and services. Many decision support tools (DSTs), developed to address global changes in forest management practices, reflect the complexity of the scientific knowledge produced, a fact that could make it difficult for pract...

The production of maple syrup is an important cultural and economic activity directly related to the climate of northeastern North America. As a result, there are signs that climate change could have negative impacts on maple syrup production in the next decades, particularly for regions located at the southern margins of the sugar maple (Acer sacc...

Survey questionnaire. Survey questionnaire in the format presented to participants, with total responses indicated for each question. (PDF)

Conditional inference (CI) classification trees. Selected conditional inference classification tree predicting the response rates of survey questions using only predictors identified as important during the random forest variable importance evaluation step of the analyses (see Table 1). For each tree, only significant predictors at p ˂ 0.05 were re...

Full dataset. Excel file containing the full dataset used for analyses. Column numbers correspond to Table 3 and S1 File. The geographic locations of the sugar bushes (i.e. latitude and longitude coordinates) have been removed from the table to ensure the anonymity of the respondents. (XLSX)

The present study proposes and exemplifies a methodology to estimate the carbon stock from aerial biomass.Essentially, the method combines field data from forest inventory to obtain site specific measurements of carbonstock, and airborne LiDAR (ALS) data to derive proxy variables of forest structure. We then model and spatializecarbon predictions.F...

Science and society are increasingly interested in predicting the effects of global change and socio-economic development on natural systems, to ensure maintenance of both ecosystems and human well-being. The Intergovernmental Platform on Biodiversity and Ecosystem Services has identified the combination of ecological modelling and scenario forecas...

Aim of study: To assess the effectiveness for improving early seedling performance of the individual and combined application of (i) various doses of an innovative soil conditioner including polyacrylamide-free super-absorbent polymers, fertilizers, root precursors and humic acids; and (ii) innovative mulches based on renewable-biodegradable or rec...

The persistence of non-serotinous pines in Mediterranean forests can be threatened by climate-mediated changes in fire regimes that may favor the dominance of resprouters or other fire-adapted species. Recovery of non-serotinous pines after large wildfires is often determined by their ability to grow under the canopy of promptly established resprou...

Assessing the perception of key stakeholders within the forest sector is critical to evaluating their readiness to engage in adapting to climate change. Here, we report the results of the most comprehensive survey carried out in the Canadian forestry sector to date regarding perceptions of climate change. A total of 1158 individuals, representing a...

Socio-demographic information of respondents. Distribution by gender, age, education level, province, stakeholder and political view of respondents in a survey on perceptions of climate change in the Canadian forest sector. (PDF)

Survey responses by type of stakeholder. Responses by type of stakeholder for the first three sections of a survey on perceptions of climate change in the Canadian forest sector. (PDF)

Conditional inference trees. Conditional Inference (CI) classification trees for predicting perceptions of climate change and its impacts on forest ecosystems across the Canadian forest sector. (PDF)

Survey responses by province of respondent. Responses by province of origin for the first three sections of a survey on perceptions of climate change in the Canadian forest sector. (PDF)

Restoring degraded ecosystems is a global challenge. Wherever applicable, forest restoration is one of the most effective tools for reversing degradation processes and enhancing multiple ecosystem services. In Mediterranean semiarid conditions the main limiting factor for tree establishment is the low and irregular precipitation regime, which has a...

Research into mixed-forests has increased substantially in the last decades but the extent to which the new knowledge generated meets practitioners’ concerns and is adequately transmitted to them is unknown. Here we provide the current state of knowledge and future research directions with regards to 10 questions about mixed-forest functioning and...

Understanding the effects of forest management on biodiversity is a vital challenge given the current regime of large-scale socio-ecological drivers affecting forest ecosystems and their multifunctionality. Here we assessed how forest management affects abundances of common breeding birds in mountain pine (Pinus uncinata Ram. ex DC) stands in the P...