Licheni come indicatori di continuità ecologica in foreste subalpine: casi di studio nella Foresta di Paneveggio (NE Italia)

2006/2007In the Italian Alps subalpine forests are still intensively managed for timber production. The increasing interest on near-to-nature silvicolture has favoured a scientific-based and multi-purpose management approach whose models are often developed on the basis of ecological studies in the remnant near-natural sites. This could apply also to lichens, whose role in biodiversity conservation in subalpine coniferous forests of the Italian Alps is still largely unknown. Thus, testing the relations between tree parameters, the availability of different types of Coarse Woody Debris (CWD) in different decay stages and the richness and composition of lichen communities in near-natural stands could be a first step to gather information for forest managers interested in conservation and in biodiversity assessment and monitoring. This thesis summarize the results of four case studies, carried out in near-natural sites in the Paneveggio Forest (NE Italy). They were focused on the evaluation of the influence of tree age and age-related parameters and CWD in shaping species richness and composition of lichen communities. In two complemetary sections the influence of forest management on epiphytic lichens and the suitability of a standard assessment of lichen diversity to predict total species richness are also evaluated. Tree-level lichen diversity and composition proved to be related to the main features of the trees such as age and size. Several lichens, including nationally rare species, are related to old trees (more than 200 years old), which are normally absent in managed forests. The macrolichen Letharia vulpina, which is a relatively dispersal limited species related to old-trees is suggested as a potential indicator of tree growth continuity. Its use as an indicator species is strongly enhanced since it is easily identifiable by non-specialists. Also CWD has an important role for lichen diversity in subalpine forests. Stumps, which are the main type of available CWD in managed stands, host several nationally rare species, which are related to different stages of wood decay. However, the presence of different types of CWD in different decay stages proved to enhance several nationally rare species, indicating that the retention of logs, snags and stumps should be included in management plans aiming at improving naturalistic silvicolture in the Alps. The relations between lichen communities and some structural features of mature forests such as over-mature trees and different types of CWD in different decay stages suggest their suitability for evaluating tree growth- and forest continuity, and conservation importance of subalpine forests of the Alps. Lichens should be therefore included in the framework of indicators which are used to evaluate the effectiveness of forest management for biodiversity conservation in the Alps.Nelle Alpi italiane le foreste subalpine di conifere sono ancora intensamente utilizzate per la produzione di legname. Il crescente interesse verso la selvicoltura naturalistica ha tuttavia favorito un approccio gestionale polifunzionale i cui modelli sono spesso sviluppati sulla base di studi ecologici condotti nei pochi siti prossimo-naturali ancora rimasti. Questo approccio ben si adatta ai licheni, il cui ruolo nella conservazione della biodiversità nelle foreste subalpine a conifere delle Alpi italiane è ancora poco conosciuto. Pertanto, testare le relazioni tra le caratteristiche degli alberi, la disponibilità di diversi tipi di legno morto in diversi stadi di decomposizione e la ricchezza e composizione delle comunità licheniche in siti prossimo-naturali rappresenta un primo contributo all’acquisizione di informazioni applicabili nel contesto di una gestione forestale attenta alla conservazione della biodiversità. Questa tesi risssume i risultati di quattro casi di studio condotti in siti prossimo-naturali all’interno della Foresta di Paneveggio (NE-Italia) e focalizzati sulla valutazione dell’influenza dell’età degli alberi (e di parametri ad essa collegati) e del legno morto sulla ricchezza specifica e la composizione delle comunità licheniche. In due studi complementari viene inoltre valutato l’effetto della gestione forestale sui popolamenti di licheni epifiti e viene testata l’efficacia di un metodo standardizzato per misurare la diversità lichenica epifita nel predire la ricchezza specifica totale a livello di albero. La diversità e la composizione dei popolamenti lichenici a livello di albero è risultata essere correlata alle principali caratteristiche degli alberi come l’età e le dimensioni. In particolare, molti licheni rari a livello nazionale risultano correlato agli alberi ultra-maturi con più di 200 anni, che normalmente sono assenti nelle foreste gestite a scopo produttivo. Il macrolichene Letharia vulpina, specie a dispersione relativamente limitata e correlata agli alberi vetusti, è un potenziale indicatore di continuità ecologica a livello di albero. Il suo impiego come specie indicatrice è inoltre favorito dal fatto che si tratta di un lichene facilmente riconoscibile da parte di personale non specializzato. Anche il legno morto ha un ruolo importante per la biodiversità lichenica nelle foreste subalpine. Le ceppaie, che rappresentano il principale tipo di legno morto nei boschi produttivi, ospitano molti licheni rari a livello nazionale che sono correlati a diversi stadi di decomposizione del legno. Tuttavia anche la presenza di diversi tipi di legno morto in diversi stadi di decomposizione è importante per molte specie rare e pertanto nei piani di gestione naturalistica delle foreste alpine si dovrebbe considerare il parziale mantenimento, oltre alle ceppaie, di tronchi morti in piedi e al suolo. Le relazioni tra le comunità licheniche e alcuni aspetti strutturali delle foreste prossimo-naturali come la presenza di alberi vetusti e di diversi tipi di legno morto in diversi stadi di decomposizione, suggeriscono la possibilità di utilizzare i licheni per valutare la continuità ecologica e l’importanza conservazionistica delle foreste subalpine delle Alpi. I licheni dovrebbero pertanto essere inclusi nel set di indicatori che vengono utilizzati per valutare l’efficacia della gestione forestale nella conservazione della biodiversità.XX Ciclo196

An integrated system for producing user-specific keys on demand: an application to Italian lichens

The identification of lichens is important in several applied fields, such as the biological monitoring of air pollution and the restoration of openair stone monuments. This often creates relevant problems for non-specialists and technicians which are in charge of routinely applying lichen monitoring techniques. The coupling of a complex information system (ITALIC), together with a new software which can automatically produce identification keys for any subset of species included in a database (FRIDA), is an innovative approach in the field of identifying biodiversity. ITALIC is able to produce a list of species which potentially occur under a set of ecological and distributional conditions specified by the user. The list is automatically transferred to FRIDA, which generates a user-oriented interactive identification key limited to the species present in the “virtual habitat” created by the user. The new system has relevant applications, since it effectively supports the technical personnel of Environmental Agencies, Nature Parks, Cultural Heritage Conservation Agencies involved in lichen monitoring throughout the Country

I licheni epifiti del Parco Naturale di Paneveggio-Pale di San Martino

Da molti anni, nel Parco di Paneveggio-Pale di San Martino sono in corso ricerche sui licheni che hanno permesso di realizzare un inventario delle specie e di apportare contributi originali alle conoscenze sulla loro ecologia. Il Parco di Paneveggio ha una missione molto importante nella conservazione dei licheni: nel suo territorio ne sono noti quasi 650, pari al 50% dei licheni del Trentino-Alto Adige, che è la regione italiana con il maggior numero di specie note. Tuttavia, una stima realistica della biodiversità lichenica del Parco potrebbe essere di circa 900 specie! Il Parco ha commissionato al Dipartimento di Scienze della Vita dell'Università di Trieste la realizzazione di una guida interattiva ai licheni epifiti, che al momento include 242 specie e che è consultabile in rete dal sito del Parco o da quello del progetto Dryades (www.dryades.eu). L'identificazione dei macrolicheni (licheni fruticosi, fogliosi e squamulosi) può essere effettuata anche senza l'uso del microscopio,ed è quindi più facile. Al contrario, per l'identificazione dei licheni crostosi è spesso indispensabile osservare caratteri anatomici al microscopio, soprattuto quelli relativi alle spore

Functional over-redundancy and vulnerability of lichen communities decouple across spatial scales and environmental severity

According to the insurance hypothesis, high taxonomic diversity should ensure ecosystem stability because of functional redundancy, whereas reduced functional diversity that results from species loss should affect ecosystem sensitivity, resilience, and vulnerability. However, even in species-rich ecosystems, functional over-redundancy (FOR; i.e., the tendency of most species to cluster into a few over-represented functional entities) in some cases may result in under-representation of many functions, and the ecosystem might become highly vulnerable. Using a stratified random sampling design with nested spatial levels (nine land use strata, 70 plots, 435 trees/rock outcrops, and 9845 quadrats), we recorded the occurrence of over 350 species of epiphytic and rock-dwelling lichens in semi-arid ecosystems in western Sardinia, where solar radiation defines a wide environmental gradient. By accounting for species functional traits, such as growth form, photosynthetic strategies, and reproductive strategies, we obtained 43 functional entities (>60% of all possible combinations) and tested the scale-dependency of FOR and functional vulnerability (FV, i.e., the risk of losing functional entities) by generalized linear mixed models. We found that FOR increased and FV decreased with increasing spatial scale, which supports the hypothesis of a cross-scale functional reinforcement. Decoupling of FOR and FV was far more evident for rock-dwelling compared with epiphytic communities, which reflects differing environmental conditions associated with substrate type. Our results indicate that increased warming and climatic extremes could exacerbate species clustering into the most resistant functional entities and thus enhance FOR at the community level. Therefore, high taxonomic diversity may not ensure systematic buffering of climate change impacts

We are Losing Unknown Diversity: Case Studies from Lichens

Lichens are poikilohydric organisms resulting from the symbiosis between a fungus and a population of green algae and/or cyanobacteria. Their vital functions strictly depend both on exchanges with the atmosphere and on the chemical and physical characteristics of their substrate. Because of the fragile balance to which they are subjected, many species have suffered a considerable decline in their abundance and distribution in recent decades. Moreover, most models predict a worsening of their declines as a direct and indirect consequence of global change. In the face of this worrying picture, lichen conservation policies and actions are still largely insufficient to mitigate lichen biodiversity loss in the near future. In this presentation, we will review some of the key issues in this regard, including: (i) the insufficient level of knowledge of the distribution of most species, due to the lack of large-scale surveys, the difficulty of taxonomic identification and the poor detectability of many groups with small thalli and (ii) The almost total lack of consideration of lichen species in national and international legislation on the conservation of biodiversity. Perspective for more effective conservation will also be outlined on the basis of specific studies, aimed at finding some operational tools to counteract the loss of lichen biodiversity before knowing it

Catalogo critico dei licheni dell’Emilia-Romagna

Il presente catalogo dei licheni sinora noti per l’Emilia-Romagna si basa sull’informazione reperibile nella letteratura pubblicata fino all’anno 2016 e sistematizzata in un database di oltre 6300 record a cui sono associati metadati utili per delineare la distribuzione e l’ecologia delle specie. In alcuni casi restano aperti problemi di sinonimia e di incongruenza con precedenti cataloghi redatti a scala nazionale. Per evitarne la dispersione, questi record problematici vengono riportati in tre distinte appendici. Nel complesso, il catalogo si basa su un totale di poco più di 5900 record che documentano la presenza sul territorio regionale di 795 taxa infragenerici. Il lavoro da un lato conferma un quadro di relativa carenza di conoscenze lichenologiche n questa Regione, dall’altro potrà verosimilmente costituire un punto di riferimento e stimolo per nuove indagini

Could Hair-Lichens of High-Elevation Forests Help Detect the Impact of Global Change in the Alps?

Climate change and the anthropic emission of pollutants are likely to have an accelerated impact in high-elevation mountain areas. This phenomenon could have negative consequences on alpine habitats and for species of conservation in relative proximity to dense human populations. This premise implies that the crucial task is in the early detection of warning signals of ecological changes. In alpine landscapes, high-elevation forests provide a unique environment for taking full advantage of epiphytic lichens as sensitive indicators of climate change and air pollution. This literature review is intended to provide a starting point for developing practical biomonitoring tools that elucidate the potential of hair-lichens, associated with high-elevation forests, as ecological indicators of global change in the European Alps. We found support for the practical use of hair-lichens to detect the impact of climate change and nitrogen pollution in high-elevation forest habitats. The use of these organisms as ecological indicators presents an opportunity to expand monitoring activities and develop predictive tools that support decisions on how to mitigate the effects of global change in the Alps

Brassica and Sinapis Seeds in Medieval Archaeological Sites:An Example of Multiproxy Analysis for Their Identification and Ethnobotanical Interpretation

The genus Brassica includes some of the most important vegetable and oil crops worldwide. Many Brassica seeds (which can show diagnostic characters useful for species identification) were recovered from two archaeological sites in northern Italy, dated from between the Middle Ages and the Renaissance. We tested the combined use of archaeobotanical keys, ancient DNA barcoding, and references to ancient herbarium specimens to address the issue of diagnostic uncertainty. An unequivocal conventional diagnosis was possible for much of the material recovered, with the samples dominated by five Brassica species and Sinapis. The analysis using ancient DNA was restricted to the seeds with a Brassica-type structure and deployed a variant of multiplexed tandem PCR. The quality of diagnosis strongly depended on the molecular locus used. Nevertheless, many seeds were diagnosed down to species level, in concordance with their morphological identification, using one primer set from the core barcode site (matK). The number of specimens found in the Renaissance herbaria was not high; Brassica nigra, which is of great ethnobotanical importance, was the most common taxon. Thus, the combined use of independent means of species identification is particularly important when studying the early use of closely related crops, such as Brassicaceae

Refining the picture: new records to the lichen biota of Italy

Based on the analysis of both historical and recent collections, this paper reports an annotated list of taxa which are new to the lichen biota of Italy or of its administrative regions. Specimens were identified using a dissecting and a compound microscope; routine chemical spot tests and standardized thin-layer chromatography (TLC or HPTLC). The list includes 225 records of 153 taxa. Twenty taxa are new to Italy, the others are new to one or more administrative regions, with 15 second records and 5 third records for Italy. Some of the species belong to recently-described taxa, others are poorly known, sterile or ephemeral lichens which were largely overlooked in Italy. Several species are actually rare, either because of the rarity of their habitats (e.g. old-growth forests), or because in Italy they are at the margins of their bioclimatic distribution. The picture of the lichen biota of Italy has now new pixels, but its grain is still coarse. Further analysis of historical collections, increased efforts in the exploration of some areas, and the taxonomic revision of critical groups are still necessary to provide more complete distributional data for new biogeographic hypotheses, taxonomic and ecological research, and biodiversity conservation