Vol. IV - Global climate change impacts on natural systems in the Lombardia region
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Relazione non tecnica pag.1 Vol. IV - Global climate change impacts on natural systems in the Lombardia region Unità Operativa: Politecnico di Milano According to the IPCC Fourth Assessment Report, published in October 2007, “warming of the climate system is unequivocal, as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice and rising global average sea level” (IPCC, 2007). Anthropogenic emissions of greenhouse gases are today identified with a very high level of confidence as the cause of relevant impacts on natural systems; in the coming years these emissions can sensibly impact human activities, such as agriculture, water supplies, human health or ecosystems. Climate is in fact one of the factors that determines natural systems composition, productivity and structure. A great number of plants can successfully grow and reproduce only in a specific range of temperatures and precipitation regimes; at the same time, meteo-climatic conditions affect fauna geographical distributions, together with food resources availability. Climate change, thus, can affect ecosystems, populations and individuals directly (e.g., owing to the increase of average temperature) or indirectly (e.g., through changes in food resources availability). A comprehensive albeit qualitative assessment of climate change impacts is described in Volume II of this report. The quantitative analysis of all the expected impacts on natural systems in Lombardia is extremely complicated and is beyond the scope of this project. Therefore, in this volume we present a study on climate change effects for few charismatic species that characterize the habitats of the Lombardia region: the alpine ibex (Capra ibex ibex) in Parco dell’Adamello; the brown trout (Salmo trutta) in the upper portion of river Adda; the black grouse (Tetrao tetrix tetrix) in the Parco dell’Alpe Veglia-Devero; the chamois (Rupicapra rupicapra) in Valchiavenna. As climate change impacts on vegetation are expected on long timescales, the attention is thereby directed toward animal species, because of the shorter time scale of the response to climatic variation. Habitat suitability models have been used to study climate change impacts; these models evaluate the suitability of a certain area for a specific species on the basis of the area characteristics. Habitat suitability models describe the relation existing between presence and abundance of a species and habitat characteristics (morphological, climatic, vegetational, anthropic). Using these relations, it is possible to estimate information such as suitable areas and potential number of individuals that can be sustained by a defined area. Finally, climate change impacts on the population dynamics of alpine ibex (Capra ibex ibex) have been studied, focusing on the population in Parco del Gran Paradiso. In this analysis, scenarios of climate change were regionalised to derive stochastic series of local daily precipitation and temperature from trends simulated by global models. Lo stambecco alpino (Capra ibex) A first analysis was conducted on alpine ibex (Capra ibex ibex; Figure 1), a charismatic species, threatened with extinction in the recent past, in Parco dell’Adamello, located on the left riverside of the Vallecamonica. Parco dell'Adamello position is strategic in the Alpine arch because, together with the four surrounding parks, it covers about 250,000 ha, one of the biggest in Europe. Furthermore, between 1994 and 1997 and since 2000, re-introduction operations in the Parco dell'Adamello were carried out; knowing how ibex will respond to climate change is important in order to predict the success of the reintroduction. Progetto Kyoto Lombardia – Linea Esternalità Ambientali (2008) Relazione sintetica - Terzo Anno
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Figure 1: The ibex (Capra ibex ibex).
The ibex habitat suitability model consists of two submodels: one for winter and one for summer
habitat suitability. The wintering model depends on altitude, exposition, slope and vegetation; the
aestivation model depends on altitude only.
We considered two climate change emission scenarios among those drawn by IPCC, A2 and B2,
and the monthly average increase of temperature (with respect to 1961-1990) in the cell of Northern
Italy as simulated by Hadley Center HadCM3 model for 2020 (short term scenario) and 2050
(medium term scenario). We considered as reference period 1979-1990 because of the availability
of monthly temperature series recorded in a meteorological station close to the Parco
dell’Adamello. The increase of temperature in winter and summer seasons are in Table 1 for the A2
and B2 scenarios, in both 2020 and 2050.
In order to estimate climate change impacts on habitat suitability, altitude is considered a proxy for
temperature. Under the hypothesis that temperature varies with elevation according to a moist
adiabatic lapse rate, the ibex altitudinal ranges were re-calculated for the temperature increases of
A2 and B2 scenarios in 2020 and in 2050. As temperature raises, suitable altitudinal ranges shift to
higher elevations.
Table 1: Average temperature increases in winter and summer seasons for
A2 and B2 scenarios in 2020 and 2050; increases are simulated by
HadCM3 model for Northern Italy cell.
Winter Summer Winter Summer
2020 2020 2050 2050
(°C) (°C) (°C) (°C)
A2 0,84 2,39 2,02 4,83
B2 1,54 3,08 1,82 4,42
Results of the analysis clearly show that the ibex population distribution and consistency in Parco
dell’Adamello will be affected by climate change. Precisely, because of the projected increase of
average temperature, the population potential density will slightly increase in the winter and
strongly decrease in the summer. Figure 2 shows the suitability maps, obtained as the output of the
wintering model, for the A2 scenario in 2020 and 2050. Current suitable areas that are projected to
remain suitable in the future are coloured in yellow; current suitable areas that will become
unsuitable are coloured in pink; current unsuitable areas that will became suitable are coloured in
blue. Figure 3 shows output maps of the aestivation model for A2 scenario; as in Figure 2, yellow
areas will remain suitable in the future and pink areas are those that will be lost because they will
become unsuitable. There is a marked contraction of the 2020 suitable area, with a further
worsening in 2050. In future scenarios, the suitable area shifts toward the Eastern side of the Parco
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dell’Adamello, where the highest elevations are located. An analogous result is achieved for the B2
scenario.
In the summer, ibex potential density in Parco dell’Adamello decreases from 1,511 individuals to
891 in the best scenario (A2 – 2020) down to 380 in the worst scenario (A2 – 2050); in the winter,
potential density increases from 1,587 to 1,777 in the best scenario (A2 – 2050) and to 1,684 in the
worst scenario (A2 – 2020). The critical season is thus summer: the availability of suitable areas in
this season will act as a bottleneck for the overall ibex individuals in the Parco dell’Adamello.
Figure 2: Ibex habitat suitability maps for the winter model in Parco dell’Adamello. Yellow: areas that are currently
suitable and that will remain suitable under GCC; pink: areas that are currently suitable and that will become unsuitable
under CCG; blue: areas that are currently unsuitable and that will became suitable under CCG. The map on the left
refers to A2 – 2020 scenario, the map on the right to A2 – 2050 scenario.
Figure 3: Ibex habitat suitability maps for the summer model in Parco dell’Adamello. Yellow: areas that are currently
suitable and that will remain suitable under GCC; pink: areas that are currently suitable and that will become unsuitable
under CCG. The map on the left refers to A2 – 2020 scenario, the map on the right to A2 – 2050.
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These are preliminary analysis and the different formulation of the wintering and the aestivation
models may have caused such a dramatic difference between summer and winter potential
populations. Summer distribution depends, in fact, only on altitude. Since climate change causes a
temperature increase, ibex suitable areas move toward higher altitudes and, thus, the suitable area
decreases because it is limited by mountain peak. Even if the structure of the model may influence
the results, it is consistent with what expected to actually happen: species will be able to survive to
increased temperatures until they will be able to find, at higher elevations, habitat with climatic (but
not only) suitable characteristics. Model results may be interpreted as follow: the most critical
impacts of climate change in alpine environment will emerge for those species that are sensible to
high temperatures, in particular in the summer season.
Brown trout (Salmo trutta)
A second climate change impact assessment was carried out focusing on an aquatic species: the
brown trout (Salmo trutta; Figure 4) that lives in the upper part of river Adda (Valtellina valley),
flowing from Lovero to lake Como. Fish species are a useful indicator: being upper trophic level,
they strongly depend on water and stream flow quality. Thus, if it is possible to estimate alterations
of the fish community, it is also possible to evaluate changes of the overall aquatic environment .
Furthermore, some brown trout traits make the species a good indicator for climate change impacts
studies: habitat is strictly limited and defined by parameters such as water temperature (brown trout
prefer cold water mountain streams), dissolved oxygen, stream velocity and depth (Mohseni et al.,
2003; Hari et al., 2005).
Figure 4: Brown Trout (Salmo trutta).
To study climate change impacts on brown trout, two suitability indexes were used: one related to
the maximum water weekly temperature and the other related to the frequency of daily flows below
a minimum flowrate. The indexes vary between zero (non suitable habitat) and one (optimal
habitat). Habitat suitability depends on maximum water temperature following two functions, one
for adults and juveniles and one for fry, that require colder waters than adults (Raleigh et al., 1986).
The minimum flowrate for brown trout in the upper river Adda is estimated to be 40 m3/s (Vismara
et al., 2001), and is therefore used as reference value to estimate how many days a year the river is
not suitable because of its low flow. In addition, we have used a third index to assess the potential
fish richness depending on the river average flow.
We estimated the variation of meteo-climatic and hydrological variables under global climate
change scenarios. To calculate the two indexes, we used water weekly temperature (which was
estimated via a linear relationship between water and air temperature) and daily average flow
(which was estimated via a lazy learning algorithm using a blackbox model that relates flowrates to
air temperature and precipitation on the upper river Adda catchment basin). Emissions scenarios
considered are IPCC A2 and B2 in 2020 and 2050; future projections for temperature and
precipitation under different scenarios of climate change have been derived from the Tyndall Centre
for Climate Change Research dataset for the Hadley Center’s HadCM3 model (Mitchell et al.,
2004; Figure 5). With these data, we estimated future water temperatures and daily flows and then
calculated suitability indexes under climate change scenarios.
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Variazioni di temperatura mensili per il periodo 2050 Variazioni di precipitazioni per il periodo 2050
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Figure 5: Temperature and precipitation average changes for A1Fi, A2 and B2
emission scenarios in 2050 with respect to 1961-1990; projections are from
HadCM3 model for Northern Italy cell.
The graph in Figure 6 shows the results of the habitat suitability model that utilizes the maximum
water temperature. It results that adults and juveniles (blue bars) will not be affected by increasing
water temperature, since the indexes remain equal to one in all scenarios. Fry, instead, will be
negatively affected by warmer waters (red bars): the suitability index decreases to about 0.8 in the
A2 scenario in 2050. The frequency of days with flow below the minimum flowrate doesn’t show
marked changes in future scenarios. While baseline frequency is about 6%, it varies between 4.8%
in A2-2050 and 7% in B2-2050. The low flow frequencies show increases as well as decreases with
respect to the baseline scenario; this is consistent with uncertainties of projected precipitation
changes under climate change in Northern Italy.
1
indice di vocazionalità
0,75
0,5
0,25
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Base A2 2020 A2 2050 B2 2020 B2 2050
scenario
Figure 6: Values of the suitability index of maximum water temperature for
adults and juveniles and for fry under climate change scenarios.
Thus we can conclude that climate change impacts on brown trout in upper river Adda are estimated
to be moderate. The analysis, though, was limited by some critical aspects: first of all, the scarcity
of available data for the models’ calibration (water and air temperature) and their low quality;
available data are point measures, not averages as it would rather be. Furthermore, upper river Adda
is strongly regulated, making more difficult to model the river regime; a black box model was in
fact used to model the river discharge. A conceptual model would probably allow a better fit and
would be capable of including different phenomena affected by climate change, such as glaciers’
retreat and snowmelt.
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Black grouse (Tetrao tetrix)
In the Alpine environment, which is characterised by high biodiversity and vulnerability, the
species of the black grouse (Tetrao tetrix) is an important ecological indicator (Wöss e Zeiler,
2003). In January 2008, an European climatic atlas of birds species has been published (Huntley et
al., 2007). Using bioclimatic models, the atlas shows how global climate change will affect species
(such as the black grouse) distribution through a shift of about 550 km towards north-east by the
end of the century, with consequences on habitat availability and biodiversity.
The black grouse (Figure 7) is a large bird in the grouse family. The species doesn’t have strict
requirements in choosing its habitat; it prefers the upper limit of the forest and, as nesting sites,
vegetation made of small shrubs, rhododendrons and blueberry, which provide food and protection.
It generally avoids dense wood forests. The preferred altitude ranges between 1500 and 2200 m. A
peculiar mating ritual takes place during spring in traditional open areas (arenas) where the males
display making a highly distinctive mating call. The presence of forested slopes is equally important
because it provides suitable habitat to survive to rigid winter conditions (Parco Veglia-Devero,
2006).
Figure 7: Two male individuals of black grouse (Tetrao tetrix) during the mating ritual (left); a female
individual (right).
The habitat suitability model used in this study has been developed, calibrated and validated for the
Alpe Devero (Ranci Ortigosa, 2000), that has therefore been chosen as the study area. It is
developed on cartographic data (1:10.000 and 1:25.000 scales) of the area and it allows to evaluate
the suitability of a specified area at local level. The model distinguishes separately the
environmental features that characterize the spring arenas for the mating rituals and the areas for the
nesting and caring for the chicks. The model results are expressed in terms of probability of
presence of the species.
According to the model, the suitability highly depends on the maximum altitude and on the
vegetation patterns in both the spring (mating areas) and the summer models (nesting areas). For the
mating areas the percentage of larch forest are determinant, whilst for the nesting models the
percentage of larch forest together with rhododendron are determinant. The area of study is limited
to the Devero Alp because of the availability of a detailed vegetation map. Two emission scenarios
have been considered (A2 and B2) for three temporal horizon (2020, 2050, 2080); temperature
increases are projected through the HadCM3 AOCGM model (Table 2). Altitude is considered a
proxy for temperature; we assumed that temperature varies with elevation according to a moist
adiabatic lapse rate.
Table 2: Temperature increase (°C) as an average of monthly values.
A2, spring A2, summer B2, spring B2, summer
2020 1,10 0,94 1,28 1,54
2050 1,80 2,88 2,01 2,63
2080 3,96 5,10 2,88 3,87
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The results of the habitat suitability model for the baseline scenario, thus without considering global
climate change, show that there are large areas suitable for the black grouse within the park both in
the spring and in the summer (Figure 8). The most suitable areas are located at the base of the
slopes, at altitudes between 1800 and 2100 m.
Figure 8: Suitability maps for the spring (left) and the summer (right) models under the baseline scenario.
One of the main consequences of climate change is the shift towards higher altitudes in an attempt
to keep in pace with temperature increase. With a temperature increase of about 1°C, such as those
occurring in the spring of 2020 (that is, on average between 2010 and 2039, for the scenarios A2,
+1,095°C, and B2, +1,28°C), the corresponding altitudinal shift is of about 160 m; results show that
for such a shift there is no excessive loss of habitat. This result seems in line with the argument that
the alpine ecosystem can tolerate, at the local level, temperature increases of about 1-2°C, but can
be compromised by further increases, such as 3-4°C (Theurillat e Guisan, 2001).
With the increasing temperature, by 2050 consistent redusctions of the suitable area are projected.
For exemple, Figure 9 shows the percentages of the number of cells for each class of probability of
species occurrence for each scenario and timeframe for the spring model (note that the area upon
which statistics are calculated remains constant as is the area of study, namely the basin of Devero).
Climate change impacts on area suitability are highest for the most suitable classes (those with a
probability of species occurrence higher than 0,5). The share of pixels with probability 0,5÷0,75
dramatically decreases already by 2020; pixels with probability higher than 0,75 disappear by 2050.
Global climate change will have a relevant role impact on the black grouse: the results of the spring
and summer models shows that we can expect a sharp decrease in the suitable area. the existence of
the species might be compromise by habitat reduction.
PRIMAVERA
100%
95%
90% 0,75-1
0,50-0,75
0,25-0,50
85% 0-0,25
80%
75%
Dati storici A2-2020 A2-2050 B2-2020 B2-2050
Figure 9: Share of pixels belonging to each suitability class for the spring model.
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The chamois (Rupicapra rupicapra)
In this case study, we analysed climate change impacts on the chamois (Rupicapra rupicapra)
habitat in Val Chiavenna (Sondrio). The chamois is an important species in the alpine ecosystem;
moreover it is important for the hunting season management. A habitat suitability model for the
chamois is available, whose validity has already been tested for the area in examination (Ranci
Ortigosa 2000; Tosi et al., 1996). The alpine chamois is an herbivorous goat that lives in the
mountain or sub-mountain environment (Figure 10). The chamois prefers both the open
environments, such as high-alpine meadows, and the wooded areas. In the winter, the chamois
searches for places that offer repair and have little snow, such as slopes beaten by the wind, steep
and sunny slopes, wooded areas at medium and low altitude.
The Val Chiavenna alpine area extends for 57.603 ha between the Lepontine and the Retiche Alps.
The chamois is a stable presence in the area, even though with a low density individuals (Scherini,
1994). The population is estimated to be of about 500÷900 individuals (census data for the period
1991-1997), whilst the known culls are 4÷9% of population.
Figure 10: The alpine chamois (Rupicapra rupicapra).
The habitat suitability model is divided into two models: one is dedicated to evaluate suitable areas
for the winter, the other is dedicated to evaluate suitable areas for the summer. The wintering model
is based on the following environmental variables: altitude, slope, morphological complexity, land
use, assolation. The aestivation model depends on the following environmental variables: altitude,
slope, morphological complexity, land use and aspect. The habitat suitability function for both the
wintering and the aestivation models is given by the sum of the scores given by all individual
environmental variables. Figure 11 shows the two suitability maps for the two models for the
baseline scenario. The number of potential individuals that can be sustained by a unit of area
depends on the final score of the habitat suitability function for that unit of area; the density
potential ranges from 0 for unsuitable areas to 25 chamois per 100 ha for the most suitable areas.
The model was implemented using the software VVF developed for Grass (Ranci Ortigosa et al.,
2000).
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Figure 11: Suitability maps for the summer (left) and the winter (right) models;
suitability increases from 1 (non suitable) to 6 (optimal).
In order to evaluate the impacts of global climate change of the chamois habitat suitability, two
scenarios have been considered, A2 and B2 chosen within the IPCC emission scenarios. The
temperature variation is derived from the dataset elaborated by the Tyndall Centre for Climate
Change Research, on the basis of the HadCM3 AOGCM model results (Table 3; Mitchell et al.,
2004).
Table 3: Temperature increase (°C) as an average of monthly values.
A2, spring A2, summer B2, spring B2, summer
2020 1,10 0,94 1,28 1,54
2050 1,80 2,88 2,01 2,63
2080 3,96 5,10 2,88 3,87
Given the moist adiabatic lapse rate that correlates temperature with altitude, it has been possible to
assess how much the temperature increase, due to climate change, affects the chamois habitat
suitability. Results show that with the increase of temperature, areas with higher habitat suitability
index (HSI) decrease, whilst areas with lower HSI increase. This highlights the impacts of climate
change on the spatial distribution of the chamois in Valchiavenna: with rising temperatures, suitable
areas decrease and, moreover, there is a general decrease in the value of the habitat suitability
indexes. From the suitability maps for future scenarios it is possible to estimate the potential
number of individuals that can be sustained. The figures of the potential number of chamois in the
years 2020, 2050 and 2080 for scenarios A2 and B2 is listed in Table 4.
Table 4: Number of potential chamois for A2 and B2 scenarios.
Baseline scenario 1278 2781 1278 2781
A2, winter A2, summer B2, winter B2, summer
2020 1244 2631 1251 2406
2050 1214 2312 1235 2242
2080 1161 1767 1214 2633
Climate change impacts on the alpine ibex population dynamics in the Parco del Gran
Paradiso
The aim of this part of the research project is to assess the ecological impacts of climate change on
the dynamic of a charismatic population of the ibex at local scale; the analysis is carried out with a
Progetto Kyoto Lombardia – Linea Esternalità Ambientali (2008) Relazione sintetica - Terzo Anno
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The two models of the ibex population dynamic shows an initial increase in the number of
individuals common to all scenarios (Figure 13), this is probably due to the fact that the initial
conditions (relative to 2005) corresponds to a low stage of the population cycle. After a few years,
the number of ibex sharply increases and then, after 2020-2030, stabilizes at about 200-1000
individuals. The Jacobson et al. (2004) model is more sensitive to the differences between the
different climate scenarios than the Corani and Gatto (2007) model; results of the Jacobson et al.
(2004) model are trajectories more dispersed and with more fluctuations. Moreover, the Jacobson et
al. model is more sensitive to climate variability: for the baseline scenario the range between the
two percentiles is 2500-5500 individuals compared to 2800-4400 individuals for the Corani and
Gatto model.
The simulations of ibex population under climate change conditions show an increase in the number
of individuals up to 4000-4800 compared to 3800 in the baseline scenario. The SRES A2 scenarios
project a higher decrease in snow cover than the B2 scenarios; this, in turns, results in a higher
increase of the ibex individuals for the A2 scenarios than in the B2 scenarios, showing that
population dynamic is mainly driven by direct effects of snow depth on mortality.
Figure 12: Risultati delle simulazioni dello spessore nevoso, è riportata la mediana dello
spessore a seguito degli scenari di cambiamento climatico e dello scenario di controllo.
Figure 13: Statistiche delle simulazioni del numero di stambecchi a seguito degli scenari di cambiamento climatico e
dello scenario di controllo, effettuate con il modello di Jacobson et al. (2004) e Corani e Gatto (2007); è riportata la
mediana del numero di individui.
Progetto Kyoto Lombardia – Linea Esternalità Ambientali (2008) Relazione sintetica - Terzo AnnoRelazione non tecnica pag.12 Much caution should be used when analyzing these projections on the ibex population in the Gran Paradiso National Park. First of all, these results are at odds with recent observation of the ibex population. There is growing evidence that the advance of the growing season affects the quality and the nutritional value of the grasses on which ibex juveniles feed, hence causing an increase in mortality rates. Moreover, the results of the habitat suitability models applied to the ibex in Adamello Park showed a sharp decrease in suitable habitat because of climate change and, thus, a decrease in the number of ibex that can be sustained by the park. It is problematic to use only population dynamic models to assess climate change impacts because the model doesn’t take in account indirect effect that could be critical for the ecological system; indirect climate change impacts should be introduced through specific conceptual models. In particular, it could be very interesting, as a continuation of this research, to use habitat suitability models to estimate the population carrying capacity and then to integrate this results in a population dynamic model in order to consider the increase in intraspecific competition due to the reduction of available resources. 1.1. Adaptation policies and conclusions The climate system is destined to undergo continuous changes in the next centuries: human activities will continue to impacts the climate system; even if greenhouse gas emissions would abruptly stop, there will still be climatic changes. For this reason, we must take action not only to mitigate emissions, but also to adapt to the inevitable consequences of climate change. Species may respond to changes brought by climate change, in different ways: they can adapt to new conditions; move their lifetimes traits over time or move in space, where conditions are still adequate or have become so; if the environmental changes are sudden and do not allow species to adapt or migrate, species will go extinct at local level and, in the event of changes over the whole area of distribution, at global level. Species and organisms have developed various mechanisms to monitor climatic conditions under which they have adapted to live and reproduce; therefore they are able to adapt "autonomously" to climate change. However, this is a very limited capacity because in the absence of significant evolutionary change (which generally requires tens of thousands of years or more), species depend only on their innate ability to respond to climate change. If suitable habitats disappear or change faster than the population adaptive capacity, species will undergo extinction (Malcolm et al., 1998). It is important to underlie that, at least in this century, evolutionary changes will not play an important role in the adaptation of species to climate change (Malcom and Pitelca, 2000). The conservation of biodiversity, of natural ecosystems and of their functions is essential not only for their intrinsic value and for the services they provide to human society, but also for the strict interactions with the climatic system. The sequestration of carbon by natural vegetation, soil, forests, agricultural areas (the terrestrial biosphere) is, in fact, a key component of the carbon cycle. On the other hand, there are several processes that can turn the biosphere from a sink to a source of carbon: fires, pests, violent floods, heat waves, increased water stress and other extreme events. Administrators and all stakeholders should consider a priority to develop policies and measures to reduce the negative impacts of climate change on biodiversity and ecosystems. In particular, the goal should be to increase ecosystems resilience of thus reduce their vulnerability, so that they can respond and adapt to climate change. The adaptation policies should take into account the high degree of uncertainty associated with climate change and its impacts on ecosystems. Where possible, synergistic positive results should be pursued when developing adaptation policies (so-called win-win policy): for example to promote the preservation of an ecosystem and, at the same time, to contribute to greenhouse gas emissions Progetto Kyoto Lombardia – Linea Esternalità Ambientali (2008) Relazione sintetica - Terzo Anno
Relazione non tecnica pag.13 mitigation through the enhancement of carbon sequestration in the terrestrial biosphere. Policies should be flexible and able to adapt to situations that rapidly change: climate is no longer one of environmental constant used to develop conservation measures. Today, under climate change, attention is focused more on adaptive management, that is based on a dynamic and flexible approach in which measures are planned, implemented and carefully monitored (Mitchell et al., 2007; Peterson et al., 1997). Four key elements for ecosystems adaptation policies can be identified (Mitchell et al., 2007): (1) reduce the direct impacts; (2) reduce the indirect impacts; (3) increase the resilience, (4) facilitate changes. The measures that can be taken to implement these policies are described below. - Direct management of ecosystems in order to reduce impacts. The direct management of ecosystems refers to situations where intervention, such as changing the microclimate or soil drainage, can allow organisms to persist in their current location. - To promote the dispersal of species, and to allow species to move into new areas with a suitable climate. Measures that have been proposed include the establishment of ecological corridors and stepping stones that connect the main patches of the habitat. At the same time, we must improve the quality of environmental matrix in which the patches are. The implementation of this strategy strongly depends on species and habitat characteristics. The ecological corridors can also encourage undesired effects, such as the spread of invasive species; in this case, monitoring and counter- measures are essential. - To increase the available habitat, both by enlarging existing patches or by creating new ones, in order to favours the increase of resilience. On the one side, it increases the population size, on the other it increases the diversity of climates and, therefore, there are more possibilities that there will be suitable areas even under climate change. - To reduce pressures other than climate change. In order to reduce ecosystems and species vulnerability, it is of major concern to pursue the reduction of all those impacts that are not directly linked to climate change (eg, water and air pollution, fertilizer and chemical compounds leakages, habitats fragmentation, land use change). As already mentioned, together with adaptation policies, a long term monitoring of the results of the policies implemented should be carried out. It is also important to monitor climate change and its impacts on species and ecosystems. Obviously, without monitoring, it would not be possible to evaluate the success (or failure) of the implemented measures, and to adjust them in order to make them as much effective as possible. Finally, the importance of the availability of a robust knowledge base of climate change and of its impacts on species and ecosystems is stressed out. Without this knowledge, the design of effective adaptation policies becomes more and more complicated. It is important to reduce the uncertainties and to increase the understanding of the processes that drive changes and to further develop the ability to estimate projected changes. Unfortunately, to date, this knowledge base in Lombardy, and in Italy in general, is rather fragile. In Italy, Alps are the only areas from which data are considerate reliable by IPCC’s AR4; according to IPCC (Parry et al., 2007) data are deemed reliable if they derive from at least 20 years long studies and if they show significant changes even in disagreement with global climate change. There is lack of impacts assessment on biological systems throughout the rest of the national territory. This shows a serious weakness in a country that is in the list of global biodiversity hotspots, both terrestrial (Myers et al., 2000) and marine (Bianchi and Morri, 2000). Progetto Kyoto Lombardia – Linea Esternalità Ambientali (2008) Relazione sintetica - Terzo Anno
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