114 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
Predicting wild boar damages to croplands in a mosaic of agricultural and natural areas
Crop damages by wildlife is a frequent form of human-wildlife conflict. Identifying areas where the risk of crop damages is highest is pivotal to set up preventive measures and reduce conflict. Species distribution models are routinely used to predict species distribution in response of environmental changes. The aim of this paper was assessing whether species distribution models can allow to identify the areas most at risk of crop damages, helping to set up management strategies aimed at the mitigation of human-wildlife conflicts. We obtained data on wild boar Sus scrofa damages to crops in the Alta Murgia National Park, Southern Italy, and related them to landscape features, to identify areas where the risk of wild boar damages is highest. We used MaxEnt to build species distribution models. We identified the spatial scale at which landscape mostly affects the distribution damages, and optimized the regularization parameter of models, through an information-theoretic approach based on AIC. Wild boar damages quickly increased in the period 2007-2011; cereals and legumes were the crops more affected. Large areas of the park have a high risk of wild boar damages. The risk of damages was related to low cover of urban areas or olive grows, intermediate values of forest cover, and high values of shrubland cover within a 2-km radius. Temporally independent validation data demonstrated that models can successfully predict damages in the future. Species distribution models can accurately identify the areas most at risk of wildlife damages, as models calibrated on data collected during only a subset of years correctly predicted damages in the subsequent year
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
Inconsistent recognition of uncertainty in studies of climate change impacts on forests
Petr, M., Vacchiano, G., Thom, D., Mairota, P., Kautz, M., Gonçalves, L. M. D. S., ... Reyer, C. P. O. (2019). Inconsistent recognition of uncertainty in studies of climate change impacts on forests. Environmental Research Letters, 14(11), 1-13. [113003]. https://doi.org/10.1088/1748-9326/ab4670Background. Uncertainty about climate change impacts on forests can hinder mitigation and adaptation actions. Scientific enquiry typically involves assessments of uncertainties, yet different uncertainty components emerge in different studies. Consequently, inconsistent understanding of uncertainty among different climate impact studies (from the impact analysis to implementing solutions) can be an additional reason for delaying action. In this review we (a) expanded existing uncertainty assessment frameworks into one harmonised framework for characterizing uncertainty, (b) used this framework to identify and classify uncertainties in climate change impacts studies on forests, and (c) summarised the uncertainty assessment methods applied in those studies. Methods. We systematically reviewed climate change impact studies published between 1994 and 2016. We separated these studies into those generating information about climate change impacts on forests using models -'modelling studies', and those that used this information to design management actions-'decision-making studies'. We classified uncertainty across three dimensions: nature, level, and location, which can be further categorised into specific uncertainty types. Results. We found that different uncertainties prevail in modelling versus decision-making studies. Epistemic uncertainty is the most common nature of uncertainty covered by both types of studies, whereas ambiguity plays a pronounced role only in decision-making studies. Modelling studies equally investigate all levels of uncertainty, whereas decision-making studies mainly address scenario uncertainty and recognised ignorance. Finally, the main location of uncertainty for both modelling and decision-making studies is within the driving forces-representing, e.g. socioeconomic or policy changes. The most frequently used methods to assess uncertainty are expert elicitation, sensitivity and scenario analysis, but a full suite of methods exists that seems currently underutilized. Discussion & Synthesis. The misalignment of uncertainty types addressed by modelling and decision-making studies may complicate adaptation actions early in the implementation pathway. Furthermore, these differences can be a potential barrier for communicating research findings to decision-makers.publishersversionpublishe
How robust are future projections of forest landscape dynamics? Insights from a systematic comparison of four forest landscape models
Projections of landscape dynamics are uncertain, partly due to uncertainties in model formulations. However, quantitative comparative analyses of forest landscape models are lacking. We conducted a systematic comparison of all forest landscape models currently applied in temperate European forests (LandClim, TreeMig, LANDIS-II, iLand). We examined the uncertainty of model projections under several future climate, disturbance, and dispersal scenarios, and quantified uncertainties by variance partitioning. While projections under past climate conditions were in good agreement with observations, uncertainty under future climate conditions was high, with between-model biomass differences of up to 200 t haâ1. Disturbances strongly influenced landscape dynamics and contributed substantially to uncertainty in model projections (~25â40% of observed variance). Overall, model differences were the main source of uncertainty, explaining at least 50% of observed variance. We advocate a more rigorous and systematic model evaluation and calibration, and a broader use of ensemble projections to quantify uncertainties in future landscape dynamics
Harmonized dataset of surface fuels under Alpine, temperate and Mediterranean conditions in Italy. A synthesis supporting fire management
Surface biomass characterization plays a key role in wildfire management. It allows classifying vegetation fuels flammability for fire risk analysis, to define silvicultural prescriptions for fire hazard reduction, to plan prescribed burning, or to model fire behavior and its effects, such as greenhouse gas and pollutant emissions. To facilitate fuel classification and analysis of potential fire behavior and effects in Italy, we harmonized 634 measurements of surface wildland fuels from Alpine, temperate and Mediterranean environments. The dataset provides quantitative data for duff, fine dead fuels and downed woody material, live grasses and shrubs fuel components. Surface fuel data were harmonized by subdividing loads (Mg ha(-1)) to standard size classes for dead (0-6, 6-25 and 25-75 mm) and live (0-6, 6-25 mm) fuels, collecting percent cover and depth/height (cm) of the various fuel components, and classifying observations into 19 fuelbed categories. To ensure comparability with existing vegetation classification systems, we classified each observation according to the European Fuel Map, the Corine Land Cover classes (level IV), the European Forest Types, and the forest categories of the Italian National Forest Inventory. The dataset and a photo description of each fuelbed category are available as Supplementary material. This dataset is the first step to develop several products at the national scale such as: (i) fuel type classification and mapping; (ii) carbon stock and wildfire emission estimates; (iii) calibration of fuel models for the simulation of fire behavior and effects
Translating land cover/land use classifications to habitat taxonomies for landscape monitoring: A Mediterranean assessment
Periodic monitoring of biodiversity changes at a landscape scale constitutes a key issue for conservation managers. Earth observation (EO) data offer a potential solution, through direct or indirect mapping of species or habitats. Most national and international programs rely on the use of land cover (LC) and/or land use (LU) classification systems. Yet, these are not as clearly relatable to biodiversity in comparison to habitat classifications, and provide less scope for monitoring. While a conversion from LC/LU classification to habitat classification can be of great utility, differences in definitions and criteria have so far limited the establishment of a unified approach for such translation between these two classification systems. Focusing on five Mediterranean NATURA 2000 sites, this paper considers the scope for three of the most commonly used global LC/LU taxonomiesâCORINE Land Cover, the Food and Agricultural Organisation (FAO) land cover classification system (LCCS) and the International Geosphere-Biosphere Programme to be translated to habitat taxonomies. Through both quantitative and expert knowledge based qualitative analysis of selected taxonomies, FAO-LCCS turns out to be the best candidate to cope with the complexity of habitat description and provides a framework for EO and in situ data integration for habitat mapping, reducing uncertainties and class overlaps and bridging the gap between LC/LU and habitats domains for landscape monitoringâa major issue for conservation. This study also highlights the need to modify the FAO-LCCS hierarchical class description process to permit the addition of attributes based on class-specific expert knowledge to select multi-temporal (seasonal) EO data and improve classification. An application of LC/LU to habitat mapping is provided for a coastal Natura 2000 site with high classification accuracy as a result
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