Martina Pollastrini

University of Florence | UNIFI · Agriculture Food Environment and Forestry

Quercus ilex L. dieback has been reported in several Mediterranean forests, revealing different degree of crown damages even in close sites, as observed in two Q. ilex forest stands in southern Tuscany (IT). In this work, we applied a novel approach combining dendrochronological, tree-ring δ13C and genetic analysis to test the hypothesis that diffe...

Riassunto Il monitoraggio estensivo delle condizioni delle foreste in Italia (Livello I-rete Con.Eco.For.-ICP Forests) ha messo in evidenza un progressivo peggioramento delle chiome, con una significativa tendenza all'aumento della defogliazione e della mortalità degli alberi nel periodo 2010-2022. I valori più alti di defogliazione coincidono con...

Climate change in progress: observations on the impacts of drought events on Tuscan forests The empirical observation of the impacts of drought and heat waves that occurred between 2017 and 2022 in several forest areas of Tuscany allowed to describe various processes and effects on forest trees and shrubs. The most severe impacts were observed on t...

Tree diversity and species identity are known to play an important role in modulating forest productivity and its capacity to buffer the effects of climatic events. The FunDivEurope exploratory platform allowed us to analyse this modulating effect in a medium-term time span, after an abrupt rise to a new stable level of the average summer temperatu...

Chlorophyll a fluorescence (ChF) signal analysis has become a widely used and rapid, non-invasive technique to study the photosynthetic process under stress conditions. It monitors plant responses to various environmental factors affecting plants under experimental and field conditions. Thus, it enables extensive research in ecology and benefits fo...

Climate change is impairing tree physiology and growth, causing an increase in tree dieback in many Mediterranean forests. These desiccation phenomena are leading to changes in land cover and plant community composition. Mediterranean plants are capable to emit large amount of Biogenic Volatile Organic Compounds (BVOCs), whose emission and biosynth...

Photosynthesis rates and electron transport are key physiological traits that distinguish the successional status of plants (early successional – ES, and late successional – LS) in a community. ES plants can respond quickly to sudden changes in sunlight radiation exposure and display a greater photosynthetic plasticity, with respect to the LS ones,...

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...

Tree defoliation and mortality are triggered in Europe by extreme climatic events that are recurring since the beginning of XXI century. Data from the ICP Forests monitoring networks reveal a general worsening of tree conditions in the last ten years, as consequence of the drought and heat waves that affected the Southern (2017) and Central Europe...

The taxonomic interpretation of Mediterranean oaks of Quercus sect. Quercus (Fagaceae): uncertainties and diverging concepts .-Fl. Medit. 31 (Special Issue): 271-278. 2021.-ISSN: 1120-4052 printed, 2240-4538 online. The high degree of polymorphism found in the genus Quercus is certainly the main cause of the divergent taxonomic treatments that have...

Tree species diversity promotes multiple ecosystem functions and services. However, little is known about how above- and belowground resource availability (light, nutrients, and water) and resource uptake capacity mediate tree species diversity effects on aboveground wood productivity and temporal stability of productivity in European forests and w...

Abstract: Forest health and multifunctionality are threatened by global challenges such as climate change. Forest health is currently assessed within the pan-European ICP Forests (International Cooperative Programme on Assessment and Monitoring of Air Pollution Effects on Forests) programme through the evaluation of tree crown conditions (defoliati...

Forest ecosystems have a crucial role for biodiversity conservation, providing a large set of ecosystem services. Understanding and assessing forest disturbance regimes on a large spatial and temporal scale is a prerequisite setting up sustainable forest management solutions. In this context, Remote Sensing is an efficient tool frequently used in l...

The potential ecological envelope of silver fir (Abies alba Mill.) based on its present distribution suggests a high suitability for moist rather than warm and dry environments. This contrasts with paleoecological evidence reporting its former presence at low elevations under meso-Mediterranean conditions. In this study, we evaluated the growth per...

The definition of stress comes from the physical sciences and refers to the ability of a force applied to a material to induce a deformation (strain). Unlike materials, living organisms and biological systems react to stress with responses to prevent or repair the damage. Plants exposed to stressful conditions move from an optimal (non-stressed) to...

Microcystis is a genus of unicellular blue-green algae that is toxic and can be troublesome in freshwater, especially where organic material is abundant. The aim of this work was to analyse photosystems photochemistry of Microcystis spp. colonies under salt stress by the use of comprehensive chlorophyll a fluorescence signals measurements (prompt,...

Climate change and extreme drought and heat events impact the Mediterranean evergreen sclerophyllous vegetation in South Europe, especially in Iberian and Italian peninsula, where widespread crown defoliation and dieback have been observed since the 90s of the XX century. Field observations and long-term experiments showed different sensitivity of...

A Chlorophyll Fluorescence (ChlF) assessment was carried out on oak seedlings (Quercus ilex, Q. pubescens, Q. frainetto) of Italian and Greek provenance, during the years 2017 and 2018, in a common garden in central Italy planted in 2017. This trial aimed to test the relative performances of the oak species in the perspective of assisted migration...

Tree crown defoliation is the most widespread indicator of forest health and vitality in Europe. It is part of the ICP Forests Pan-European survey and it is adopted for reporting under Forest Europe. It is readily understandable and can count on fairly harmonized, long-term, large-scale data series across Europe. On the other hand, it is unspecific...

A Chlorophyll Fluorescence (ChlF) assessment was carried out on oak seedlings (Quercus ilex, Q. pubescens, Q. frainetto) of Italian and Greek provenance, during the years 2017 and 2018, in a common garden in central Italy planted in 2017. This trial aimed to test the relative performances of the oak species in the perspective of assisted migration...

Replicate common gardens of Italian and Greek provenances of Quercus ilex, Q. pubescens, and Q. frainetto seedlings were established in 2017 in Italy, Greece, and Germany (here: also Q. robur) to assess their potential for plantations for future climate scenarios. The JIP-test was applied on saplings (2016) and in the summers of 2017-2019 to assess...

Plant growth reduction (GR) is the most widely accepted damage parameter to assess the sensitivity of trees to tropospheric ozone (O 3) pollution since it integrates different physiological processes leading to loss of photosynthetic activity and distraction of metabolic resources from growth to defense, repair, and recovery pathways. Because of th...

An anomalous event of drought and heat occurred in central Italy during the summer of 2017. Based on the SPI (Standardized Precipitation Index) and data from the European Space Agency, this event started in November 2016 and was characterized by a strong reduction of precipitation and soil moisture, especially in lowland areas with Mediterranean cl...

Global warming and climate change are the topic most discuss in the last past decades. It is well known that plants communities and forests ecosystems are affected by the increasing of the average temperatures and by extreme precipitations and drought, events that are always more frequent and intense (1). The response of plants to climate changes i...

Forests are subjected to impacts of climate changes, including extreme drought phenomena, which can be very harmful for seedlings therefore compromising the regeneration. Phenotipic plasticity of tree species under environmental changes can be threatened and it is expected a decrease of tolerance to climate events. Modifications of forest structure...

Many morphological, chemical and physiological indicators have been proposed to evaluate the conditions of plants in ecological systems. Among them, the analysis of the prompt fluorescence (PF) of chlorophyll is considered a powerful tool that combines the richness of the achievable information with the operational quickness. This technique is espe...

Plants display a large number of traits which are reflected in physiological and ecological functions (functional traits). Leaf traits are amongst the most important functional traits. However, a great challenge in measuring leaf traits in the field is that direct methods are limited by the cost of the instruments and the time and work required by...

Tree diversity is found to enhance ecosystem functions in forests and increase the resistance and resilience of trees subjected to environmental stress, including climate change. This effect, however, can be different depending on tree species assemblages and ecological contexts. The pan-European programme for monitoring forest health (ICP Forests)...

Global climate change is expected to result in more frequent and intense drought events, especially during the warm season. In such perspective, it is crucial to assess the forest stands vulnerability to extreme climatic events, such as drought, even for Mediterranean forest tree species, commonly considered resistant to dry spell. To test the capa...

Forest health is currently assessed in Europe (ICP Forests monitoring program). Crown defoliation and dieback, tree mortality, and pathogenic damage are the main aspects considered in tree health assessment. The worsening of environmental conditions (i.e., increase of temperature and drought events) may cause large-spatial scale tree mortality and...

Tree health monitoring provides important information for conservation, management and improvement of forest resources. Such monitoring began in Europe in the '80s, as part of the pan-European ICP-Forests program, to respond to the concerns arising from the impact of pollutants and atmospheric depositions. Currently, forest monitoring has seen its...

Forest ecosystem functioning generally benefits from higher tree species richness, but variation within richness levels is typically large. This is mostly due to the contrasting performances of communities with different compositions. Evidence‐based understanding of composition effects on forest productivity, as well as on multiple other functions...

Introduzione Il faggio è una delle principali specie forestali in Italia e in Europa. L'estensione e la struttura dei suoi boschi è determinata dalla produzione di seme, che in questa specie è caratterizzata da variazioni sincrone, con eventi di fruttificazione abbondante, chiamati pasciona. La pasciona è quel fenomeno che si manifesta quando tutti...

Forest diversity and tree health relationships in Italian forests depend on environmental context

Sustainable forest management (SFM) is crucial for forest ecosystem productivity and conservation, especially in systems such as cork oak (Quercus suber L.) threatened by human activities and biotic and abiotic factors. In this study SFM indicators with particular reference to cork oak forests in the region of Sardinia (Italy) are proposed and test...

Average nitrogen (N) deposition across Europe has declined since the 1990s. This resulted in decreased N inputs to forest ecosystems especially in Central and Western Europe where deposition levels are highest. While the impact of atmospheric N deposition on forests has been receiving much attention for decades, ecosystem responses to the decline i...

Introduction Chlorophyll fluorescence (ChlF) analysis, especially the prompt fluorescence (PT), offers a large array of parameters useful to study the responses of plants under environmental stress. Stress factors induce specific physiological responses, related to the efficiency of the photosynthetic apparatus, that can be assessed with a proper s...

This study presents a reanalysis of ozone (O3) exposure experiments performed on deciduous broadleaf oak species in the Mediterranean region and a proposal of critical levels to improve the O3 risk assessment in this area for these widely distributed forest species. Two experiments performed in Spain and Italy were considered, and the following 3 o...

The dataset supplied in this article provides data from a stand of Pinus nigra J.F.Arnold subsp. calabrica (Poir.) Maire (Calabrian black pine) characterized by old trees, with a relevant role for forest community biodiversity. Natural stands of Calabrian black pine have both outstanding conservation and cultural values, to be taken under considera...

During the summer 2017, central Italy has been hit by an intense drought and heat wave, with temperatures higher than 40�C and problems for drinking water supply. In the same period, impacts on forest trees have been observed, such as early foliar shedding in deciduous broadleaved tree species and diffuse desiccation of leaves and branches in everg...

Humans require multiple services from ecosystems, but it is largely unknown whether trade-offs between ecosystem functions prevent the realisation of high ecosystem multifunctionality across spatial scales. Here, we combined a comprehensive dataset (28 ecosystem functions measured on 209 forest plots) with a forest inventory dataset (105,316 plots)...

The importance of biodiversity in supporting ecosystem functioning is generally well accepted. However, most evidence comes from small-scale studies, and scaling-up patterns of biodiversity–ecosystem functioning (B-EF) remains challenging, in part because the importance of environmental factors in shaping B-EF relations is poorly understood. Using...

Different tree species influence litter decomposition directly through species‐specific litter traits, and indirectly through distinct modifications of the local decomposition environment. Whether these indirect effects on decomposition are influenced by tree species diversity is presently not clear. We addressed this question by studying the decom...

The concern for the fate of forest ecosystems under climate change demands the development of a prompt and effective system for detecting the impacts of pressure factors, such as rising temperatures, drought conditions, and extreme climatic events. In ongoing European monitoring programs, the health condition of trees is only assessed visually as a...

Using chlorophyll (Chl) a fluorescence many aspects of the photosynthetic apparatus can be studied, both in vitro and, noninvasively, in vivo. Complementary techniques can help to interpret changes in the Chl a fluorescence kinetics. Kalaji et al. (Photosynth Res 122:121-158, 2014a) addressed several questions about instruments, methods and applica...

An assemblage of tree species with different crown properties creates heterogeneous environments at the canopy level. Changes of functional leaf traits are expected, especially those related to light interception and photosynthesis. Chlorophyll a fluorescence (ChlF) properties in dark-adapted leaves, specific leaf area, leaf nitrogen content (N) an...

Il Manuale descrive le procedure per ottenere dati relativi a “nuovi” indicatori per valutare lo stato di salute e vitalità degli alberi in chiave funzionale. Documento del progetto LIFE FutureForCoppiceS, Azione B.2

Earthworms have a significant influence on the structure, composition and functioning of forest ecosystems, but in spite of their role as ecosystem engineers, little is known on the factors controlling their distribution across European forests. Optimised sampling techniques, as well as more advanced statistical tools and geographical information s...

Drought frequency and intensity are predicted to increase in many parts of the Northern Hemisphere and the effects of such changes on forest growth and tree mortality are already evident in many regions around the world. Mixed‐species forests and increasing tree species diversity have been put forward as important risk reduction and adaptation stra...

• The variability of chlorophyll fluorescence parameters (ChlF) of forest tree species was investigated in 209 stands belonging to six European forests, from Mediterranean to boreal regions. • The modifying role of the environmental factors, forest structure and tree diversity (species richness and composition) on ChlF signature was analyzed. • A...

Climate changes are expected to increase the conditions of aridity in many regions of the world and, therefore, water and heat stress events that affect natural vegetation and cultivated plants (Manes & Blasi, 1995; Hoerling et al., 2001; iPCC, 2013; Diffenbaugh & Field, 2013; Mariotti et al., 2015). the eu Biodiversity strategy to 2020 promotes al...

There is considerable evidence that biodiversity promotes multiple ecosystem functions (multifunctionality), thus ensuring the delivery of ecosystem services important for human well-being. However, the mechanisms underlying this relationship are poorly understood, especially in natural ecosystems. We develop a novel approach to partition biodivers...

There is considerable evidence that biodiversity promotes multiple ecosystem functions (multifunctionality), thus ensuring the delivery of ecosystem services important for human well-being. However, the mechanisms underlying this relationship are poorly understood, especially in natural ecosystems. We develop a novel approach to partition biodivers...

An UV-exclusion experiment was conducted on Mediterranean plant species grown in pots: the evergreen sclerophyllous shrub Arbutus unedo and the deciduous woody crop Vitis vinifera. After 130 days, of exclusion of UVB and both UVA and UVB radiations, during leaf unfolding and development, the plants were exposed to the ambient solar radiation (about...

Significance Numerous studies have demonstrated the importance of biodiversity in maintaining multiple ecosystem functions and services (multifunctionality) at local spatial scales, but it is unknown whether similar relationships are found at larger spatial scales in real-world landscapes. Here, we show, for the first time to our knowledge, that bi...

Many experiments have shown that local biodiversity loss impairs the ability of ecosystems to maintain multiple ecosystem functions at high levels (multifunctionality). In contrast, the role of biodiversity in driving ecosystem multifunctionality at landscape scales remains unresolved. We used a comprehensive pan-European dataset, including 16 ecos...

A European-wide assessment of chlorophyll a fluorescence (chlF, prompt fluorescence on dark- Adapted samples) parameters in forest ecosystems was carried out in the years 2012-2013, within the 7FP FundiveuroPe project. a total of 1596 trees growing in 209 stands distributed in six countries, from Mediterranean to boreal sites, were sampled. this pa...

The ICP-Forest program for the monitoring of forest conditions includes the assessment of ozone symptoms in the European forests. This contribute to discussion points out the problems related to the recognition of such symptoms, with a special focus on the difficulties to extend the results obtained in experimental conditions to woody plant species...

The presence of the American root-rot disease fungus Heterobasidion irregulare Garbel. & Otrosina was detected in Italian coastal pine forests (Pinus pinea L.) in addition to the common native species Heterobasidion annosum (Fries) Brefeld. High levels of tropospheric ozone (O 3) as an atmospheric pollutant are usually experienced in Mediterranean...