Organizer: Aitor Ameztegui (CTFC-CREAF)
Title: Using packages ‘tidyr’ and ‘dplyr’
* Seminari CEMFORSeminari CEMFOR
Time: 11:30 am
* R SEMINARR SEMINAR
Time: 9:15 am
Organizer: Aitor Ameztegui (CTFC-CREAF)
Title: Using packages ‘tidyr’ and ‘dplyr’
Speaker: Antoine Cabon (Ph.D. student, CTFC-CREAF)
Title: The ecohydrological equilibrium hypothesis allows quantifying the soil water supply of drought prone forests.
Abstract: In water-limited ecosystems, such as Mediterranean ones, the amount of water plants can access (i.e. the Soil Water Supply, SWS) is a key determinant of forest demography (e.g. tree growth and mortality) and function (e.g. water and carbon fluxes).
Although the link between soil moisture (θ) and soil water extractability by plants can be modelled through pedotransfer functions, the estimation of SWS is limited by the difficulty to measure the plants rooting depth (Z) and their Fine Roots Distribution (FRD) in the soil profile.
Here we estimate Z and FRD for different forest plots located in Catalonia (Northeast Spain), where θ or transpiration (E, approached by
sap flow measurements) observations were available, using simplified representation of plant hydraulics and the Eco-Hydrological Equilibrium (EHE) hypothesis. We assume that forest stands conform to this hypothesis and that their root system is therefore optimized in order to maximize transpiration within the limits of acceptable drought stress, characterized using species-specific critical levels of leaf water potentials (ψ).
We simulate ψ, E and θ for different combinations of Z and FRD with a simple water balance model and use the simulations to approach the local actual values of Z and FRD by 1) hypothesizing optimized species root system and by 2) calibrating our model against E or θ observations. Estimates from both methods were in close agreement when water was a most limiting factor, therefore sustaining our initial hypothesis.
Our method has the potential to palliate the lack of data concerning the root system of drought prone forests using only information on stand structure and plant hydraulic properties and could therefore enhance the modelling of water fluxes at large spatial scales.
Speaker: Aitor Ameztegui (Marie Curie fellowship, CREAF)
Title: Managing stand density to enhance the adaptability of Scots pine stands to climate change: a modelling approach
Abstract: La mayoría de los modelos climáticos para la región mediterránea predicen periodos de sequía más frecuentes e intensos, que pueden afectar al crecimiento y mortalidad de los árboles en amplias zonas de su distribución actual. Uno de los tratamientos selvícolas que se baraja para mitigar los impactos del cambio climático es reducir la densidad de arbolado mediante claras. Sin embargo, aún no está claro cómo responderán las masas forestales a diferentes regímenes de claras en función del escenario climático, ni conocemos bien la dinámica post-clara del balance hídrico. En este estudio exploramos estos aspectos para masas de pino albar (Pinus sylvestris) mediante modelización, acoplando un modelo de dinámica forestal con un modelo mecanístico de humedad del suelo y estrés hídrico. Nuestros resultados muestran la existencia de trade-off entre el incremento de productividad y la ganancia en disponibilidad hídrica provocada por las claras. Además, dichos mecanismos dependen de la estación y el clima, por lo que no sería recomendable aplicar recetas generalistas sin tener en cuenta estos factores.
Speaker: Miquel De Cáceres (CTFC/CREAF)
Title: Estimating daily meteorology at the landscape scale: The R package ‘meteoland’
Abstract: Reliable meteorological data are a basic requirement for hydrological and ecological studies at the landscape scale. Given the large spatial variation of topographic features in complex reliefs, meteorological records from a single weather station are often not representative of entire landscapes. Moreover, studies addressing the impacts of climate change on forests and landscapes require downscaling coarse-scale predictions of climate models to the landscape scale. With the aim to assist research of climate impacts on forests, the R package ‘meteoland’ provides utilities to estimate daily weather variables at any position in complex terrains:
In this seminar I will overview the data structures, functions and procedures of the R package ‘meteoland’ using the Solsonès county as study area.
Speaker: Maria Triviño (Univesitat de Jyväskylä, Finlàndia)
Title: Optimizing management to reduce trade-offs between multiple objectives in boreal production forests
Abstract: I will give first an overview of the work carried out at the Boreal Ecosystems Research Group (http://bit.ly/B_E_R_G). Then, I will present the results of one of the studies where we are applying multiobjective optimization to find the optimal combination of forest management regimes that provide as high levels as possible of (i) timber harvest revenues, (ii) carbon storage and (iii) suitable habitat for a number of key boreal species.
Speaker: Luke Kelly Resum: Fire is a natural process that shapes ecosystems worldwide. However, the frequency of fires has been modified by climate change and population growth, and inappropriate fire regimes threaten biodiversity in Australia and the Mediterranean Basin. There is an urgent need to predict the responses of biodiversity to future fires. I will present a brief overview of my work on optimal fire histories for biodiversity conservation using case studies from Australian shrubland and forest ecosystems. I will also outline some of the work I am planning with collaborators at the CTFC and CREAF with a focus on Mediterranean ecosystems. This includes developing a suite of models and tools that will enhance our capacity to design and evaluate alternative fire management strategies in Australian and Mediterranean landscapes. Finally, and perhaps most importantly, I will be answering the question ‘Why is there an Australia living in Solsona?”.
Speaker: Aitor Améztegui (Juan de la Cierva CTFC/CREAF) Title: Shade tolerance and functional traits: a complex relationship Abstract: Despite being instrumental in forest ecology, the definition and nature of shade tolerance are complex and not beyond controversies. Moreover, the role it can play in the trait – demography relationship remains unclear. We hypothesized that shade tolerance can be achieved by alternative combinations of traits depending on the species’ functional group (evergreen gymnosperms vs. deciduous angiosperms), and that its ability to explain the array of traits involved in demography in low light environments would also vary between these two groups. We tested these hypotheses using 48 tree species– dispersed across 21 genera and 13 families – from temperate and boreal forests worldwide, and we assessed the relationship between functional traits, shade tolerance and demographic performance at high and low light. The results support the existence of a divergence between evergreen gymnosperms and deciduous angiosperms in the way shade tolerance relates to the demography of species along light gradients. We will discuss the implications of these findings, which affect the utilization of shade tolerance as predictor of forest dynamics and species coexistence, and the nature of shade tolerance itself. Note: the seminar will be given in Spanish, with slides in English. Hope to see you all there!
Speaker: Asaf Karavani (Msc student; UdL)
Title: Effect of climatic and micro-climatic conditions on the provisioning of fungal-based ecosystem services in Mediterranean pine stands
Abstract: Mushrooms are one of the most important non-wood forest products in the Mediterranean Basin, providing a wide variety of ecosystem services. Soil moisture is assumed to be an important micro-climatic variable affecting mushroom productivity since it integrates climate, site variables and forest stand characteristics. With the aim to increase our understanding of the interaction between climate and micro-climate, and their relative role in determining mushroom occurrence and productivity, we used a long-term yield data-base from 28 permanent mushroom inventory plots established in 2008 in Pinus pinaster stands under coastal Mediterranean climate. Mushrooms were collected on a weekly basis during the autumn fruiting season and classified as total, edible and marketed mushrooms. A process-based soil water balance model was used to reconstruct soil moisture values to complement field observations. Mixed-effect two-stage models employing monthly climate and micro-climate (soil moisture) variables were fitted to mushroom occurrence and productivity data. We found that mushroom production in the Mediterranean was primarily dependent on weather conditions during the same month, with the exception of precipitation, whose effects were found to exhibit a delay of one-month. Temperature had both positive and negative effects, with high temperatures limiting production at the beginning of the fruiting season and low temperatures limiting it at the end. Although climate-based models had better predictive power than micro-climate-based models, the latter allowed more profound insight into the processes of mushroom fruiting.
Speaker: Daniel Burgas (Univesitat de Helsinki, Finlàndia)
Title: From biodiversity of boreal forests to animal tracking in the desert
Abstract: Driven by the current biodiversity crisis, my work circles around conservation issues. In this talk I will present an overview of my research lines. To start, a taste of my PhD work will provide some thought on linking raptors to biodiversity. Second, I will present my current work (in concert with the University of Helsinki and the University of Jyväskylä) on alternative forest management practices affecting biodiversity and how affecting attitudes of forest managers may play help to achieve conservation goals. Finally, I will give a brief overview on a couple of side projects monitoring biodiversity in tropical forests of Madagascar and in Kenyan arid landscapes.
Speaker: Núria Pou (Biodiversity Area, CTFC)
Title: A supporting information tool for Environmental Impact Assessments: a useful product for the Catalan administration
The CTFC, in its mission of transferring scientific knowledge to society, generates each year a set of products (manuals, tools, plans …). In this seminar, I will present a supporting information tool for conducting Environmental Impact Assessments, which is a useful product oriented to facilitate the tasks of the “Servei de Projectes” of the Government of Catalonia.
The tool includes results from research projects that have been developed in recent years in the Biodiversity area, such as species distribution models developed in the CARTOBIO project, evaluation of the pressure to which endangered species are exposed etc. Based on the information available on the projects to be evaluated by the Government (localization, actions etc.) and the results of our research studies, we provide a tool to assist the process of environmental impact assessments.