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The goal of this study is to assess the impact of different thinning approaches for coppice conversion into high forest of Turkey oak stands in Italy. The stand structure and the tree/shrub diversity were analyzed in 27 long-term monitoring plots from 7 experimental trials in the Colline Metallifere district (Tuscany, Central Italy) to verify the consistency of the original cultivation goals with the current stand structures. Three different approaches were applied from 1969 onwards: thinning from below, selective thinning, and no-management. Three indexes of specific diversity (Specific Richness, Shannon index and Importance Value) and two indexes of vertical diversity (Vertical Evenness and Coefficient of variation of tree height) were used to analyze and compare the outcome of management practices. The results showed a significantly higher dimensional variability and basal area, and a more complex vertical diversity in control plots and in the plots subject to selective thinning, as compared with plots subject to thinning from below. Tree species richness was high in all plots, independently of the thinning type applied. Based on our results, we suggest Turkey oak-dominated transitory stands to be initially managed by thinning from below, which is easy to be implemented and economically feasible. Selective thinning may be applied later with the aim of promoting sporadic but valuable tree species and increasing tree species diversity.

The paper deals with the work undertaken since 1995 within the national level II network framed into the ICP-Forests ICP-IM programme. A synthesis of results from tree growth monitoring and relationships with stand structure and related parameters, are reported. Current changes in the growth medium, i.e. physics and chemistry of atmosphere and soil, (increase of average air temperature, rainfall shortage and drought, CO2 enrichment, ozone level, nitrogen fertilization, sulphate deposition) drive today the soil-tree-atmosphere relationships. The overall result of these concurrent and counteracting factors is recorded along each growing seasons by radial stem growth, it providing a sensitive response. A few occurrences of disturbances to growth at regional and at case-study level, likely due to climate deviations, are discussed. Seasonal fluctuations and anomalous or extreme events are, as a matter of fact, the major evidences over the last decade. The heat wave 2003 is the main case occurred over a large part of Europe. Growth rate 2000-04 compared with 1997-2000, showed reductions up to 50% on plots located within the Southern continental border of the heat wave. These occurred more specifically at low elevations and for pre-determined early growth species (beech and oaks). Over the following time-window 2005-09, a significant growth decrease was vice versa detected within the coniferous spruce forests located at medium-high elevation in the Alps, where repeated seasonal anomalies both in air temperature and rainfall were recorded over the same time-span. The heavy effect of climate disturbance at a local scale is finally examined where two oak species with different auto-ecology grow together at the same site. Reasons why and awaited goals from protocols’ updating and the more intensive surveys applied to core-areas in 2009-10 under LIFE+FutMon, are reported. Perspectives at short to medium term of monitoring programme at national and European level are finally debated.

Current National Forest Inventory highlight the further increase over the last two decades of coppice area under the position of mature standing crop or in the post-cultivation phase, both being developed throughout the original cultivation area. This pattern, mainly due to the unprofitable fuel wood harvesting, also involved holm oak and beech forests, some of the most diffused forest covers in Sardinia, along the Apennines and pre-Alps. The alternative management option to ageing (the pro-active way of coppice conversion into high forest) has been also practiced in the public domain, but on much smaller areas as compared with those undergoing post-cultivation phase. Aged coppices located into medium-good site classes showed a positive growth pattern resulting in a high, age-related, wood matter storage. At the meantime, regular mortality occurring since former rotation into the fully-stocked shoot populations, stocked up high deadwood amounts, this becoming an outstanding attribute of these types. Carbon storage is becoming one of the major tasks attributable to these systems within the post-cultivation phase. Purposes are here to: (i) estimate living woody and standing + lying deadwood mass densities; (ii) determine deadwood/living mass ratio; (iii) verify lying deadwood decay class; (iv) analyse diversity between two sites aged likewise but different as for geographical location and tree species. A holm oak coppice aged 55 in Sardinia and a beech coppice aged 57 in Tuscany were selected at the purpose. Both stands have been developing the post-cultivation phase since two-three times the traditional rotation and represent the maximum ages in this position. Living and standing dead woody dry mass density were determined in each site by specific allometric functions. Lying deadwood amount was assessed by a sampling design covering systematically the full test area. Three decay classes were determined according to Hunter (modified). The tree species, both shade-tolerant, showed a similar pattern as for time of wood formation and its transfer to deadwood, as well. The main difference consists only in their evergreen and deciduous habit. Auto-ecology seems to be the main driver of stand development as for carrying capacity, mortality rate and survival time into the overstocked stand structures. Leaf standing mass and leaf /thin branches ratio are two and three times higher in holm oak, consistently with its biology. Living woody mass density is made basically by stem and thick branches (88%) and varies from 322 Mg ha-1 (beech) to 225 Mg ha-1 (holm oak). Deadwood amount ranges from 28 to 25 Mg ha-1 i.e., from 9 to 11% of living woody mass. Standing deadwood is 70 to 73% of total amount. As for lying material, the intermediate decay class is prevailing: 74%, (beech) and 66% (holm oak). Both dynamics and age-related data suggest the active role these types may play in soil conservation, improvement of forest quality and carbon storage. The need of a consistent monitoring of the further post-cultivation progress is finally stressed to recognize driving forces acting, the onset of possible limiting factors and feedbacks.

A few concurrent and/or counteracting factors (increase of average air temperature, rainfall shortage, drought, CO2 enrichment, ozone, nitrogen fertilization, sulphate deposition) drive today the soil-tree-atmosphere relationships in the Mediterranean area. Radial stem growth measured within the ICP-Forests level II Italian network provides a sensitive response to these occurrences. Climate fluctuations and repeated anomalous seasons or extreme events are the major evidences of the change in progress. The 2003 heat wave is the main event occurred in this decade over large part of Europe. In Italy, it provoked a marked water deficit coupled to high air temperature, which resulted in a heavy water stress. The growth performance in different forest types was analyzed in this paper: growth rate in 2000-2004, compared with 1997-1999, showed reductions up to 50% on half of the plots examined. Most of them were: (i) in northern-central Italy within the southern continental border of the climatic deviation; (ii) at low elevation, which is more sensitive to high air temperature and drought; (iii) made up of deciduous broadleaved forests (beech and oaks), i.e., species showing growth effects also in the following year. Over the time-window 2005-2009, a significant growth decrease was vice-versa detected within the coniferous spruce forests located at medium-high elevation in the Alps. Repeated seasonal deviations in temperature and rainfall were recorded in the Alps in 2005-2009. Climate effects at local scale were examined in a site where two oak species with a different auto-ecology (sessile oak and Turkey oak) grow together. The on-going change produced heavy mortality and reduced the growth of the more demanding and less drought-tolerant sessile oak; in a few years Turkey oak became prevailing in the stand composition and structure.

Recent data from the National Forest Inventory point out the further reinforcement of coppice area under the position of “mature” standing crop or post-cultivation phase, both of them being spread throughout the original cultivation area. Such condition, mainly due to the less profitable fuel wood harvesting, involves also a share of the more productive types, i.e., Turkey oak forests. Here, a diffuse but forced approach among managers is to “wait and see”. The pro-active way of coppice conversion into high forest is otherwise being practiced in the public domain but on much smaller areas. Against management dilemmas, ageing stands growing under medium to good site conditions show a dynamic growth pattern resulting in a high age-related wood matter storage. At the same time, the heavy and prolonged regular mortality occurring in the fully-stocked shoot population builds up high amounts of deadwood, this becoming an attribute of these newly-formed types. Carbon storage is therefore coming to be one of the major tasks attributable to these systems within the post-cultivation phase. Aims of the work are to estimate both densities of living woody mass and standing+lying deadwood without any lower survey limit, given the small-sized stems building up these types; to check deadwood types/living biomass ratios; to survey deadwood decay; to analyse the dynamics of mass storage within the stands. Three case-studies, aged about three times the traditional rotation and different as for location and site-index, were selected at the purpose. Living woody mass density plus standing and lying deadwood per decay class were determined. Living woody mass density, made basically by stem+thick branches (95%), varies within 160 and 310 Mg ha-1. Total deadwood amount ranges from 22 to 30 Mg ha-1, i.e., 9 to 14% of living woody biomass. The lying/standing deadwood ratio is being reversed with ageing from 1/2 to 2/1-3/1. The intermediate decay class is prevailing (60-85%) across the sites. The observed dynamics and the age-related figures as well, suggest the role these types may play in soil conservation, forest recovery and carbon storage. The need of a consistent monitoring of the further post-cultivation progress is stressed to recognize the driving forces acting, the onset of possible limiting factors and feedbacks.

Mediterranean sclerophyllous forests are coenoses worthy of great care because of their inherent bio-ecological value. The suspension of harvesting following the crisis of fuel wood market ruled the evolutive pattern of maquis over the last decades. In this phase, site quality seems to be the major driver of the holm oak-dominated forest recovery as well as of the lasting permanence of the sclerophyllous shrub forest. In this connection, stand dynamics has been monitored in three plots located in the strictly protected area of the “Parco Regionale della Maremma” (Grosseto - Tuscany), where natural evolution is in progress since at least five decades. The monitored stands are representative of different evolutive phases from the holm oak-dominated coppices to the typical maquis, as a function of the original stand structure and composition but also of the intensity and length of the applied coppice management system. The analysis was carried out by permanent transects; two inventories were undertaken in 1991 and 2006 to evaluate both compositional and structural variability and the dynamics in progress. Results at now highlight the role played by the residual site quality and specific composition in driving the evolutive pattern of tree species community. Under the absence of any silvicultural practice and better site conditions, the progress and specific incidence of regular mortality and the related aboveground biomass redistribution, supported the vegetation of holm oak and the other subsidiary species typical of more mature stages. The overall forest dynamics seemed anyway to proceed slowly and resulted in a steady physiognomy over a long time since the suspension of the historical disturbance made of repeated harvesting on short rotations.

The paper reports the development of allometric equations to estimate tree phytomass in Turkey oak stands in Tuscany. Biomass estimation is a basic tool to study the ecosystem, which is currently taking on a greater importance due to the commitments provided by the Climate Convention and the Kyoto Protocol. The high costs of the field measurements of tree biomass calls for the application of indirect methods, such as the largely-applied biomass equations, allowing to calculate phytomass values using variables easily measurable in the field, such as tree diameter and height. The equations described here have been developed for Turkey oak coppices undergoing conversion into high forests. Such stands are nowadays more and more common because of the progressive suspension of timber harvesting on an increased part of the original coppice area. We report five equations: the first one to estimate stem volume, and the followings to estimate each phytomass component (stem, branches, and slash) and the total tree above-ground phytomass. Tree diameter at breast height and total tree height were used as independent variables (predictors). All equations were developed on the same model and the additivity of the phytomass components in respect to the total phytomass was achieved. Equation parameters showed a fairly good accuracy in the estimation of the dependent variables.