92 research outputs found
GESTIONE DEL BOSCO E CONSERVAZIONE DELLA BIODIVERSITA': L'ANALISI ECOPAESISTICA APPLICATA A TERRITORI BOSCATI DELLA TOSCANA MERIDIONALE
This research, developed for a wooded area of Southern Toscana with both the evergreen and deciduous broadleaves woods, aims to
show the consequences of coppice management on biodiversity and to suggest a methodology useful to foster biological conservation.
An analysis of landscape spatial confi guration was carried out according to principles of landscape ecology and using birds as indicators,
by means of already available data describing this territory. The connection between the territory and biodiversity has been analysed at
different spatial scales to understand if the perception limits of wooded land and their changes, caused by implementation of forestry
strategies by a forest technician can be analogous to that of birds. Scenarios were built according to different constrains applied to management
to estimate the impact of different utilisation criteria on resources spatial pattern and therefore on biodiversity. These criteria
were then tested in a public estate managed according to a forest management plan. The most relevant conclusions of this research can
be summarised as follows:
1. at a regional level the Colline Metallifere territory is important for establishing ecological continuity. Forestry and ecological planning
should always approach the territory at different scales;
2. structural heterogeneity, for this case study, affects biodiversity in an apparently contradictory way. The management criteria adopted
favour bird species linked to high forest environment but are disadvantageous to species linked to open ground. Forest policy of past
decades leading to reforestation of former fi elds and pastures, rural depopulation inducing the secondary succession on abandonedfarmland and longer coppice rotations resulted in a strong reduction of open areas. These are important habitats for birds, which all
over the Mediterranean area are menaced;
3. growth processes cause structural changes at the stand level and therefore mosaics originated by different stand structures can be
considered as âfragileâ. Changes in the landscape due to these processes increase homogeneity and therefore may act on biodiversity
in a negative way;
4. several limitations adopted in building the scenarios correspond to rules already adopted in standard management plans, which do
not take biodiversity specifi cally into consideration;
5. empirical data on biodiversity collected in coppices, which could support or reject these hypotheses, are lacking; fi eld research is
mostly needed;
6. different behaviour of various bird species in the coppice habitat show the need to adopt strict and clear concepts regarding indicator
species or umbrella species and to avoid generic statements about âfaunaâ, âbirdsâ or âhabitatâ to evaluate biodiversity
Opportunities for coppice management at the landscape level: the Italian experience
Coppice silviculture has a long tradition in Italy. Societal demands have led to
the development of forest management techniques for integrating wood production
with other kinds of forest uses and regulations have been issued to
limit forest degradation. In Italy, 35% of the national forest cover is currently
managed under coppice silvicultural systems that provide 66% of the annual
wood production. Fuel-wood demand is increasing and a large amount of fuelwood
is currently imported in Italy. Modern coppice practices differ from those
adopted in the past and may have a reduced impact on ecosystem characteristics
and processes. Nevertheless, coppice silviculture has a bad reputation
mostly on grounds that are beyond economic, technical and ecological rationales.
Neither cessation of use nor a generalized conversion from coppice to
high forest are likely to respond simultaneously to the many demands deriving
from complex and articulated political and economic perspectives operating at
global, European, national, regional and forest stand-level scales. Different
approaches of modern silviculture to coppice successfully tested in Italy for
more than a decade are illustrated. We propose to combine different options
at the stand and sub-stand level, including either development without human
interference or conversion to high forest, and to apply these approaches
within the framework of novel forest management plans and regionally consistent
administrative procedures. This bottom-up approach represents a potential
solution to the socio-economic and environmental challenges affecting
coppicing as a silvicultural system
Impact of woody encroachment on soil organic carbon and nitrogen in abandoned agricultural lands along a rainfall gradient in Italy
Land use changes represent one of the most important components of global environmental change andhave a strong influence on carbon cycling. As a consequence of changes in economy during the last century, areas of marginal agriculture have been abandoned leading to secondary successions. The encroachment of woody plants into grasslands, pastures and croplands is generally thought to increase the carbon stored in these ecosystems even though there are evidences for a decrease in soil carbon stocks after land use change. In this paper, we investigate the effects of woody plant invasion on soil carbon and nitrogen stocks along a precipitation gradient (200â2,500 mm) using original data from paired experiment in Italian Alps and Sicily and data from literature (Guo and Gifford Glob Change Biol 8(4):345â360, 2002). We found a clear negative relationship (-0.05% C mm-1) between changes in soil organic carbon and precipitation explaining 70% of the variation in soil Cstocks after recolonization: dry sites gain carbon (up to? 67%) while wet sites lose carbon (up to -45%). In our data set, there seem to be two threshold values for soil carbon accumulation: the first one is 900 mm of mean annual rainfall, which separates the negative from the positive ratio values; the second one is 750 mm, which divides the positive values in two groups of sites. Most interestingly, this threshold of 750 mm corresponds exactly to a bioclimatic threshold: sites with\750 mm mean annual rainfall is classified as thermo-mediterranean sites, while the ones [750 mm are classified as mesomediterranean sites. This suggests that apart from rainfall also temperature values have an important influence on soil carbon accumulation after abandonment. Moreover, our results confirmed that the correlation between rainfall and trend in soil organic carbon may be related to nitrogen dynamics: carbon losses may occur only if there is a substantial decrease in soil nitrogen stock which occurs in wetter sites probably because of the higher leaching
Two centuries of masting data for European beech and Norway spruce across the European continent
Tree masting is one of the most intensively studied ecological processes. It affects nutrient fluxes of trees, regeneration dynamics in forests, animal population densities, and ultimately influences ecosystem services. Despite a large volume of research focused on masting, its evolutionary ecology, spatial and temporal variability and environmental drivers are still matter of debate. Understanding the proximate and ultimate causes of masting at broad spatial and temporal scales will enable us to predict tree reproductive strategies and their response to changing environment. Here we provide broad spatial (distribution range-wide) and temporal (century) masting data for the two main masting tree species in Europe, European beech (Fagus sylvatica L.) and Norway spruce (Picea abies (L.) H. Karst.). We collected masting data from a total of 359 sources through an extensive literature review and from unpublished surveys. The dataset has a total of 1747 series and 18348 yearly observations from 28 countries and covering a time span of years 1677-2016 and 1791-2016 for beech and spruce, respectively. For each record, the following information is available: identification code; species; year of observation; proxy of masting (flower, pollen, fruit, seed, dendrochronological reconstructions); statistical data type (ordinal, continuous); data value; unit of measurement (only in case of continuous data); geographical location (country, Nomenclature of Units for Territorial Statistics NUTS-1 level, municipality, coordinates); first and last record year and related length; type of data source (field survey, peer reviewed scientific literature, grey literature, personal observation); source identification code; date when data were added to the database; comments. To provide a ready-to-use masting index we harmonized ordinal data into five classes. Furthermore, we computed an additional field where continuous series with length >4 years where converted into a five classes ordinal index. To our knowledge, this is the most comprehensive published database on species-specific masting behaviour. It is useful to study spatial and temporal patterns of masting and its proximate and ultimate causes, to refine studies based on tree-ring chronologies, to understand dynamics of animal species and pests vectored by these animals affecting human health, and it may serve as calibration-validation data for dynamic forest models.The paper was partly funded by the âFondo di Ricerca Locale 2015-2016â of the University of Torino and by the Stiftelsen Stina Werners fond (grant SSWF 10-1/29-3 to I.D.)
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