Forests In Tuscany Research Articles

Drivers and patterns of community completeness suggest that Tuscan Fagus sylvatica forests can naturally have a low plant diversity

European beech (Fagus sylvatica L.) forests can have a high variability in plant species richness and abundance, from monospecific stands to highly species-rich communities. To understand what causes the low plant diversity observed in some beech forests, we analyzed the drivers of plant community completeness in 155 vegetation plots. Data were collected in mature, closed-canopy beech forests in Tuscany, central Italy. Site-specific species pools were estimated based on species co-occurrences. We used Generalized Least Squares linear modeling to assess the effects of anthropogenic and environmental drivers on the community completeness of whole communities and on the set of specialist species of beech forests. We also tested the response of the total cover of the herb layer to the selected predictors and related both the predictive and response variables to species composition in a Non-metric Multidimensional Scaling ordination. The community completeness of whole communities and that of beech forest specialists were negatively affected by total beech cover and positively influenced by slope. Moreover, the community completeness of whole communities was negatively impacted by elevation and positively influenced by disturbance frequency. The cover of the herb layer decreased with increasing beech cover, elevation, and precipitation. High community completeness and high cover of the herb layer were associated with the presence of thermophilic species of mixed deciduous woods in low-elevation beech forests. Our results suggest that a low plant community completeness and a low cover of the herb layer are mainly due to the competition by beech itself when it forms pure forests in its ecological optimum. Such competition is better exerted at upper elevations and in sites with low slopes, where beech litter accumulation is a limiting factor for understory species. Such evidence suggests that species absence in mature beech forests is mainly due to natural drivers and should therefore not be considered an indicator of ecological degradation of the forest.

Cork oak (Quercus suber) in the dynamism of a forest landscape shaped by fire on Monte Pisano (Tuscany N-W, Italy)

The plant landscape of Monte Pisano is characterized by a predominant forest component, with Pinus pinaster and Castanea sativa, of clear anthropic imprint. Another important component is constituted by dynamically advanced scrubs and woods of evergreen sclerophylls of natural origin, although often differently altered by the anthropic action and/or by fires, and dominated by Quercus ilex. Quercus suber is often found within holm oak woods, and – with lower frequency – inside the pine forests. Cork oak, in some cases, becomes dominant going to constitute the northernmost cork forests in Tuscany. The frequency of fires in Monte Pisano in the last decades seems to have led to an increase in Q. suber surface due to its known resilience to wildfires. The aim of this research is: a) to define the distribution of Q. suber in the area also in relation to repeated fire events in the past; b) to provide an updated characterization of these stands using a phytosociological approach; c) to identify stands and groups of trees that can be used as "seed forests" for post-fire forest restoration purpose, in relation to their marginal population characteristic. The study suggests a relationship between the spread of cork oak and the historical pattern of fires. This wide spread should be protected by forms of forest management unfortunately absent in this territory.

Physiological significance of forest tree defoliation: Results from a survey in a mixed forest in Tuscany (central Italy)

A survey of tree crown defoliation and leaf physiological traits (chlorophyll a fluorescence, nitrogen content, and stable carbon isotope composition) was carried out in the thermophilous deciduous forests in Tuscany (central Italy). In contrast to large scale surveys, where variation in defoliation can be associated with the change in environmental conditions, in a limited homogenous area the defoliation of co-existing tree species may have different significance and depends on the interaction between the characteristics of each individual species with biotic stress and environmental conditions. The survey included measurements of structural and vegetational characteristics of the forest stands, such as Leaf Area Index (LAI), basal area and tree diversity, which is expressed as the Shannon diversity index. The five tree species studied (Castanea sativa, Quercus cerris, Quercus ilex, Quercus petraea and Ostrya carpinifolia) showed species-specific crown conditions and physiological features relative to stand structure and diversity. The shape of the crowns and their area (LAI) affected forest defoliation. Tree diversity reduced defoliation in C. sativa, which was the tree species most affected by defoliation, and likewise for Q. ilex. Chlorophyll a fluorescence parameters showed lower photosynthetic efficiency in defoliated C. sativa, O. carpinifolia and Q. petraea trees. Similarly, foliar nitrogen content decreased in defoliated C. sativa and O. carpinifolia trees, whereas δ13C was higher in defoliated C. sativa. These responses may be related to the health status of C. sativa, since it was subjected to pathogen damages and insect attacks. In contrast, the mast year in O. carpinifolia may have diverted the nutrient resources from leaves to fruits, and consequently explaining the physiological effects on the tree crown. These results suggest that the combined analysis of defoliation with foliar features and stand characteristics can provide insights into tree health and vitality.

Gestione forestale sostenibile e servizi ecosistemici: un esempio di valutazione economico-finanziaria per i boschi toscani

The monetary evaluation of ecosystem services is a topic of great interest for environmental planning and forestry. However, economic measurements of forest externalities and the implementation of decision support tools able to guide decision-makers in forest assessment, are difficult tasks. In this framework, the aims of the work were: i) to define economic and financial indicators, related to appraisal of different silvicultural intervention in Tuscany forest and ii) to design a flexible economic decision support model for the guidance of stakeholders in forest management. From methodological viewpoint a short period financial analysis was developed. This analysis permits to compute stumpage value of forest harvesting. The innovative component of the work is the ability to integrate the analysis with an assessment of economic aspect of the process. As matter of fact, multifunctionality parameters and, consequently, total economic value of forest was introduced. Main results emphasize the flexibility of the implemented model and the potential application in different areas.

Improved simulation of soil water content by the combination of ground and remote sensing data

The simulation of site water balance requires the assessment of actual evapotranspiration (ETA), which is highly variable both in space and in time depending on several factors (climate, soil, vegetation). In a recent work we proposed a new method based on remotely sensed NDVI data which can estimate daily ETA operationally over large areas. The current paper utilizes these ETA estimates to drive two crop coefficient models, WinEtro and FAO56, in the prediction of soil water content (SWC). The outputs of the simulations are evaluated versus daily measurements of SWC taken in a Tuscany forest site (Barbialla) during four years. The results obtained indicate the efficiency of the proposed data combination, which improves the SWC simulations of both models examined. Recommendations are finally expressed for the possible extension and enhancement of the method described.

A spatial model for sporadic tree species distribution in support of tree oriented silviculture

This technical note describes how a spatial model for sporadic tree species distribution in the territory of the Unione di Comuni Montana Colline Metallifere (UCMCM) was built using the Random Forest (RF) algorithm and 48 predictors, including reflectance values from ground cover - provided by satellite sensors - and ecological factors. The P.Pro.SPO.T. project - Policy and Protection of Sporadic tree species in Tuscany forest (LIFE 09 ENV/IT/000087) is currently carried out in this area with the purpose of initiating the implementation of tree oriented silviculture in the Tuscany forests. Tree oriented silviculture aims at obtaining both forest biodiversity protection and local production of valuable timber. After creating a map showing the probability of presence of sporadic tree species, it was possible to identify the most suitable areas for sporadic tree species which are under protection according to the regulation of the Tuscany Region.Using data and software provided free of charge, and applying the RF algorithm, distribution models could be developed in order to identify the most suitable areas for the application of tree oriented silviculture. This can provide a support to forestry planning that includes tree oriented silviculture, thus reducing its implementation cost.

Reply: “Use of BIOME-BGC to simulate Mediterranean forest carbon stocks”

The current note responds to the critical contribution of Dr. Eastaugh on Chiesi et al. (Chiesi et al. 2011). That paper did not aim at applying BIOME-BGC to simulate stand growth, which requires a thorough modification of the model functions. In contrast, only a parameter setting was changed in order to adjust the predicted carbon storages during the simulation of quasi-equilibrium conditions. The adjustment was calibrated on volume statistics derived from the Tuscany forest inventory and is suitable for regional scale applications.

Il ceduo in Toscana: alcune riflessioni sul rapporto tra gestione forestale e risorse naturalistiche

I analyze the amount of wood samples resulting from coppicing and the recent years trend based on national and regional inventories data and on the “Report on the state of forests in Tuscany, 2008”. I highlight the difficulty in assessing a relationship between forest planning and protection of natural elements susceptible to deterioration of old forests. I also point out the difficulty of choosing appropriate indicators and investigation scale. Finally I analyze the regional laws in force, highlighting the rules can be critical for the habitat and/or the species of conservation concern.

Simulation of Mediterranean forest carbon pools under expected environmental scenarios

Simulating the effects of possible environmental changes on the forest carbon budget requires the use of calibrated and tested models of ecosystem processes. A recently proposed simulation approach based on the use of the BIOME-BGC model was applied to yield estimates of present carbon fluxes and pools in Tuscany forests (central Italy). After the validation of these estimates against existing ground data, the simulation approach was used to assess the impact of plausible climate changes (+2 °C and increased CO2 concentration) on forest carbon dynamics (gross primary production (GPP), net primary production (NPP), and relevant allocations). The results indicate that the temperature change tends to inhibit all production and allocation processes, which are instead enhanced by the CO2 concentration rise. The combination of the two factors leads to a general increase in both GPP and NPP that is higher for deciduous oaks and chestnut (+30% and 24% for GPP and +42% and 31% for NPP, respectively). Additionally, vegetation carbon is slightly increased, while total soil carbon remains almost unchanged with respect to the present conditions. These findings are analyzed with reference to the Tuscany forest situation and previous studies on the subject.

Stand structure and foliage distribution in Quercus pubescens and Quercus cerris forests in Tuscany (central Italy)

We examined vertical foliage distribution (based on destructive harvesting) in the deciduous oak species Quercus pubescens and Quercus cerris, at the level of the entire tree and the forest community, in two adjacent stands in Tuscany (central Italy). The study was aimed at characterizing the structure of these stands in a manner suitable as a biometric background for comparison with canopy processes of other forest sites. The leaf study was based on the ‘cloud’ technique described earlier, characterizing the aggregation of leaves on branches and their position in the canopy. We used regressions (based on coefficients of the double-Gauss equation) to generalize leaf distribution in individual trees and to up-scale the data for whole stands. Q. cerris trees were about six meters taller than Q. pubescens, which grew in a more xeric site. The leaf area index was lower in the stand mainly composed of Q. pubescens (LAI = 2.8) than in the Q. cerris stand (LAI = 4.7). Oak canopies occupied about one half of the stand volume and about 40% of that were ‘clouds’. The leaf area index expressed on the area of projected crown and social trees differed substantially in individual trees of different size. The projected crown to social tree area ratio (an indicator of the structural balance of a tree) reached its minimum in a defined range of tree size; such an unfavourable balance may represent a risk to the survival of trees.

Un progetto di miglioramento ambientale per il Cervo nell’Appennino Tosco-Emiliano

Abstract: The Red deer (Cervus elaphus L.) population living on the Tuscan-Emilian Apennines had in 2006 an estimated minimum size of approximately 2275 individuals, which occur in two Regions (Tuscany and Emilia-Romagna) and four Provinces (Pistoia, Prato, Florence and Bologna). Since 2000 the population has been target of selective hunting, also in order to respond to the increasing request for concrete solutions against species impact on human activities. In this note we describe a pilot experience of projecting environmental improvement actions - such as restoration and preservation of open areas - purposely intended for Red deer. Surveys concentrated on the mountainous area of Pistoia and Sambuca Pistoiese Communes and in the territories belonging to Tuscany Regional Public Property within the competence of the Pistoiese Apennines Mountain Community or within general public competence. Here, the once pastured zones are affected by the invasion and progressive colonization of arbustive and herbaceous vegetation. Areas which are currently covered by shrubs and/or other pioneer vegetation forms have been located by means of GPS technology. For each area a descriptive paper has been realized, whose aim is including the main information recollected during field surveys jointly with data inferred from the Plan for the Forest Resource Assessment in force. 16 areas we considered fitting this project’s goals have been located, for a total extent of 21 ha: on this surface extensive vegetation cutting by mowing and mulching using mechanical machinery will be carried out in the summer 2007. Where soil position allows, superficial tillage activities with subsequent sowing of autochthonous herbaceous species are planned. In the end we evaluated intervention and correct application terms of Tuscany Forest Law no. 39/00 and Tuscany Forest Regulations (D.P.G.R. no. 48/R/03).

Is vascular plant species diversity a predictor of bryophyte species diversity in Mediterranean forests?

This study aimed to (i) investigate the congruence among the species composition and diversity of bryophytes and vascular plants in forests; (ii) test if site prioritization for conservation aims by the maximization of the pooled number of vascular plant species is effective to maximize the pooled number of bryophyte species. The study was performed in six forests in Tuscany, Italy. Four-hundred and twenty vascular plant species (61 of which were woody) and 128 bryophyte species were recorded in 109 plots. Despite the good predictive value of the compositional patterns of both woody plants and total vascular with respect to the compositional pattern of bryophytes, the species richness of the latter was only marginally related to the species richness of the former two. Bryophyte rare species were not spatially related to rare plant species and neither coincided with the sites of highest plant species richness. The species accumulation curves of bryophytes behaved differently with respect to those of woody plants or total vascular plants. Reserve selection analysis based on the maximization of the pooled species richness of either woody plants or total vascular plants were not effective in maximizing the pooled species richness of bryophytes. This study indicates that species diversity of vascular plants is not likely to be a good indicator of the bryophyte species diversity in Mediterranean forests.

Recolonization Patterns of Ants in a Rehabilitated Lignite Mine in Central Italy: Potential for the Use of Mediterranean Ants as Indicators of Restoration Processes

AbstractAnt (Hymenoptera: Formicidae) assemblages were sampled with pitfall traps in three different habitats associated with a rehabilitated mine district and in undisturbed forests in Tuscany, Italy. The four habitats were (1) open fields (3–4 years old); (2) a middle‐age mixed plantation (10 years); (3) an old‐age mixed plantation (20 years); and (4) an oak woodland (40 years) not directly affected by mining activities. The aim of the study was to analyze ant recolonization patterns in order to provide insights on the use of Mediterranean ant fauna as indicators of restoration processes. Species richness and diversity were not significantly different among the four habitats. However, multivariate analyses showed that the assemblages in the different habitats were clearly differentiated, with similarity relationships reflecting a successional gradient among rehabilitated sites. The observed patterns of functional group changes along the gradient broadly accord with those of previous studies in other biogeographic regions. These were (1) a decrease of dominant Dolichoderinae and opportunists; (2) an increase in the proportion of cold‐climate specialists; and (3) the appearance of the Cryptic species in the oldest plantations, with a maximum of abundance in the woodland. In conclusion, the results of our study supported the use of Mediterranean ants as a suitable tool for biomonitoring of restoration processes, and in particular, the functional group approach proved a valuable framework to better interpret local trends in terms of global ecological patterns. Further research is, however, needed in order to obtain a reliable classification of Mediterranean ant functional groups.

Associations between Tomicus destruens and Leptographium spp. in Pinus pinea and P. pinaster stands in Tuscany, central Italy

SummaryThe association between Tomicus destruens and fungi of the genus Leptographium was studied in Pinus pinea and P. pinaster forests in Tuscany, central Italy. Fungi were isolated from adult beetles and from pine tissues from infested trees. On average, Leptographium spp. were associated with 18% of beetles in breeding galleries, 35% of emergent brood beetles and 18% of beetles undergoing maturation feeding in pine twigs. The fungal species most frequently identified were Leptographium wingfieldii and L. lundbergii while L. guttulatum and L. serpens were also found.

Assessment of stress conditions in Quercus ilex L. leaves by O-J-I-P chlorophyll a fluorescence analysis

This reasearch, carried out within the MON.I.TO. programme (Intensive Monitoring of Forests in Tuscany, central Italy), was aimed at defining the stress conditions of two Quercus ilex woods at Colognole (CL) and Cala Violina (CV). In vivo chlorophyll fluorescence was measured for a whole year (1997 - 1998) using a portable 'continuous fluorescence' fluorimeter. The fluorescence parameters were calculated using the values at the steps 0-J-I-P of the polyphasic rising transient (this analysis is called JIP-test). Measurements were performed monthly, pre-dawn and midday. The findings revealed a condition of stress (drought and high temperatures) in the summer at CV during the central hours of the day, and a winter cold stress condition at CL observed in the pre-dawn measurements. At CV, summer stress was combined with processes of biologically regulated de-excitation; at CL, the winter stress appeared to be linked to structural damage affecting the photosynthetic apparatus. Results are discussed in relation to the existing literature on stress affecting Mediterranean vegetation, and to the findings reported in previous investigations in the same study areas.

Leaf shedding, crown condition and element return in two mixed holm oak forests in Tuscany, central Italy

Litterfall (leaves, flowers, fruits, twigs) was collected every month in two mixed Mediterranean forests of Quercus ilex (holm oak) in central Italy differing for their ecological features: a mesic site (Colognole, CL) and a xeric one (Cala Violina, CV). The survey period lasted 8 years (1992–2000) at CL and 4 years at CV. Chemical analysis of the litterfall was performed in 1997 and 1998. In these 2 years living leaves were also collected for chemical analysis. The main findings were: (i) the litter production was lower and the leaf percentage in the total litterfall was smaller at CV than at CL; (ii) the phenological behavior differed in the two sites and the leaves had greater longevity at CV, whereas at CL trees renewed their crown almost completely each spring; (iii) the chemical composition of the living leaves reflected the edaphic differences between the two sites; (iv) the chemical composition of the senescent leaves and the litter in the two sites was very different; (v) crown transparency and defoliation followed the same pattern of the leaf shedding; (vi) transparency was greater at CL, where the litter production was higher, because of the different shape of the crowns. The differences between the two study areas have been discussed in the light of the different ecology of the two sites, since leaf lifespan is greater in dry and infertile soils.

Leaf morphology and macronutrients in broadleaved trees in central Italy

As part of an intensive monitoring programme (MON.I.TO, Intensive Monitoring of Forests in Tuscany), a 3-year survey was carried out, which included three tree species (beech, Fagus sylvatica L.; Turkey oak, Quercus cerris L.; holm-oak, Quercus ilex L.) located at six different sites. Leaves were sampled annually and analysed for nutrient concentrations (nitrogen, sulphur, phosphorus, magnesium, calcium, potassium and sodium) and morphological parameters (leaf area, dry weight, leaf mass per area, leaf thickness and leaf density). Results indicated considerable interannual variation of all the parameters. Differences between sampling sites indicated that, of all parameters measured, leaf mass per area could explain best the differences in field performance under conditions of stress. In fact, leaf mass per area was greater in the drier sites or when sea salt deposition occurred. Nevertheless, the variation of leaf mass per area over the 3 years did not reflect the differences in rainfall. Higher leaf mass per area was accompanied by lower concentrations of phosphorus and nitrogen, which could be a dilution effect due to an increase of structural carbon compounds in sclerophyllous leaves, as revealed by the total foliar content of these elements. Leaf mass per area as a measure of sclerophylly reached very high values among mesophile vegetation. Long-range transport of sea salt from coastal areas to mountain areas was mirrored in sodium concentrations of leaves.

Short-term changes of response indicators of ecosystem status in broadleaved forests in Tuscany (Central Italy).

The status of different response indicators of forest condition were measured and assessed between 1995 and 1997 at 6 Permanent Monitoring Plots (PMPs) in Tuscany (central Italy), where beech, holm oak and Turkey oak are the most frequent tree species. Foliage transparency, leaf damage and crown dieback have changed significantly over the monitoring period. Leaf area, length of the current year shoots, and total leaf area changed as well, but only for Turkey oak. Changes were consistent between and within the plots. Different indices of plant diversity showed marked changes, apparently linked to natural dynamics within individual ecosystems. These rapid and contrasting fluctuations in the various indicators of forest ecosystem make it difficult to derive a synthesis about the general condition of ecosystems and - especially - about the effects of air pollution.

Forest condition in Tuscany (Central Italy). Field surveys 1987–1991

Between 1987 and 1991 four surveys on the condition of forests in Tuscany (Central Italy) were carried out. The results, relating to 2275 trees in 111 sampling plots, show that the overall percentage of damaged trees (defined by the EC regulation 1696/87) increased between 1987-88 (51.4 +/- 5.4 per cent; 54.0 +/- 5.6 per cent) and 1990-91 (67.0 +/- 6.2 per cent; 64.0 +/- 6.1 per cent). The percentage of moderately and severely damaged trees also displayed an upward trend. The most severely affected species appeared to be Pinus pinea (a Mediterranean conifer, 96.7 per cent damaged trees) and Fagus sylvatica (a mountain broadleaf, 87.1 per cent damaged trees). Crown condition appeared to deteriorate with decreases in mean annual rainfall and where stand conditions are poor (thin soil, steep slopes). The findings suggest the possibility of an interaction between several different stress factors, some of which seem to be linked to local and stand conditions (exposure, silviculture, soil fertility), while others seem to be connected with long-term variations, such as changes in environmental parameters like precipitation. The actual role of background and/or local pollution can be neither demonstrated nor excluded on the basis of the present results.