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Climate change has already triggered species distribution shifts in many parts of the world. Increasing impacts are expected for the future, yet few studies have aimed for a general understanding of the regional basis for species vulnerability. We projected late 21st century distributions for 1,350 European plants species under seven climate change scenarios. Application of the International Union for Conservation of Nature and Natural Resources Red List criteria to our projections shows that many European plant species could become severely threatened. More than half of the species we studied could be vulnerable or threatened by 2080. Expected species loss and turnover per pixel proved to be highly variable across scenarios (27-42% and 45-63% respectively, averaged over Europe) and across regions (2.5-86% and 17-86%, averaged over scenarios). Modeled species loss and turnover were found to depend strongly on the degree of change in just two climate variables describing temperature and moisture conditions. Despite the coarse scale of the analysis, species from mountains could be seen to be disproportionably sensitive to climate change (≈60% species loss). The boreal region was projected to lose few species, although gaining many others from immigration. The greatest changes are expected in the transition between the Mediterranean and Euro-Siberian regions. We found that risks of extinction for European plants may be large, even in moderate scenarios of climate change and despite inter-model variability. • Intergovernmental Panel on Climate Change storylines • species extinction • species turnover • niche-based model
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Climate change threats to plant diversity in Europe
Wilfried Thuiller*
, Sandra Lavorel*
, Miguel B. Arau
, Martin T. Sykes**, and I. Colin Prentice
*Centre d’Ecologie Fonctionnelle et Evolutive, Centre National de la Recherche Scientifique-Unite´ Mixte de Recherche 5175, 1919 Route de Mende, 34293
Montpellier Cedex 5, France;
Climate Change Research Group, Kirstenbosch Research Center, National Botanical Institute, PBag x7, Claremont 7735, Cape
Town, South Africa;
Macroecology and Conservation Unit, University of E
vora, Estrada dos Leo˜ es, 7000-730 E
vora, Portugal;
Laboratoire d’Ecologie Alpine,
Centre National de la Recherche Scientifique-Unite´ Mixte de Recherche 5553, Universite´ J. Fournier, B.P. 53X, 38041 Grenoble Cedex 9, France;
Research Group, School of Geography and the Environment, Oxford University, Mansfield Road, Oxford OX1 3TB, United Kingdom; **Geobiosphere Science
Centre, Department of Physical Geography and Ecosystems Analysis, Lund University, So¨ lvegatan 12, 223 62 Lund, Sweden; and
QUEST, Department of
Earth Sciences, University of Bristol, Wills Memorial Building, Queen’s Road, Bristol BS8 1RJ, United Kingdom
Edited by Harold A. Mooney, Stanford University, Stanford, CA, and approved April 26, 2005 (received for review December 31, 2004)
Climate change has already triggered species distribution shifts in
many parts of the world. Increasing impacts are expected for the
future, yet few studies have aimed for a general understanding of
the regional basis for species vulnerability. We projected late 21st
century distributions for 1,350 European plants species under
seven climate change scenarios. Application of the International
Union for Conservation of Nature and Natural Resources Red List
criteria to our projections shows that many European plant species
could become severely threatened. More than half of the species
we studied could be vulnerable or threatened by 2080. Expected
species loss and turnover per pixel proved to be highly variable
across scenarios (27–42% and 45–63% respectively, averaged over
Europe) and across regions (2.5– 86% and 17– 86%, averaged over
scenarios). Modeled species loss and turnover were found to
depend strongly on the degree of change in just two climate
variables describing temperature and moisture conditions. Despite
the coarse scale of the analysis, species from mountains could be
seen to be disproportionably sensitive to climate change (60%
species loss). The boreal region was projected to lose few species,
although gaining many others from immigration. The greatest
changes are expected in the transition between the Mediterranean
and Euro-Siberian regions. We found that risks of extinction for
European plants may be large, even in moderate scenarios of
climate change and despite inter-model variability.
Intergovernmental Panel on Climate Change storylines species
extinction species turnover niche-based model
ecent rapid climate change is already af fecting a wide variety
of organisms (1, 2). Long-term data indicate that the anom-
alous climate of the past half-century is already affecting the
physiology, distribution, and phenology of some species in ways
that are consistent with theoretical predictions (3). Although
natural climate variation and nonclimatic factors such as land
transfor mation may well be responsible for some of these trends,
human-induced climate and atmospheric change are the most
parsimon ious explanation for many (3, 4).
Several studies have modeled future species distributions at
regional (5–8) and local scales (9, 10) and have extrapolated
alar ming extinction risks for the next century (11). However, few
studies have considered the consequences of multiple climate-
change scenarios (7, 8), which represent the outcome of different
assumptions about the future (12). Using four representative
scenarios and three dif ferent climate models (HadCM3,
CGCM2, and CSIRO2), and a range of niche-based modeling
techn iques implemented in
BIOMOD (13), we develop predictions
of the potential consequences for 1,350 plant species in Europe.
The ‘‘future climate’’ we contrast with today’s climate (averaged
f rom 1961 to 1990) is the projected mean for the period from
2051 to 2080.
The ‘‘bioclimatic envelope’’ describes the conditions under
which populations of a species persist in the presence of other
biot a as well as climatic constraints (6, 14). Future distributions
are projected on the assumption that current envelopes reflect
species’ environmental preferences, which will be ret ained under
climate change. This principle has strong support from studies
demonstrating the evolutionary conservatism of ec ological
n iches and the phylogenetic inertia of species across time scales
(15, 16) and comparative biogeographical studies (17, 18).
However, this approach also assumes inst antaneous species-
range change, it ignores physiological CO
responses, and it does
not capture details of population dynamics or biotic interactions
nor the lags in spatial range shifts associated with processes of
dispersal, establishment, and local extinction. To assess the
sensitivit y of projections to the most critical of these assump-
tions, we considered two c ontrasting assumptions about migra-
tion abilit y (7, 8, 11): either species are unable to disperse at all
on the time scale considered (no migration), or they have no
c onstraints to dispersal and establishment (universal migration).
The reality for most species is likely to fall between these
extremes, depending on their ability to migrate across frag-
mented landscapes (19). We calculated losses of climatically
suit able areas (‘‘species loss’’) assuming no migration and gains
(‘‘species gain’’) and turnover (‘‘species turnover’’) assuming
un iversal migration.
Data Sources. Species’ distribution data are available for 2,294
plants (20), comprising 20% of the total European flora,
sampled between 1972 and 1996. Modeling was c onducted by
using available data for Europe on a 50 50 km grid. The
mapped area comprises western, northern and southern Europe,
but excludes most of the eastern European countries where
rec ording effort was both less uniform and less intensive (21).
Af ter removing species with 20 records, we considered range
responses of 1,350 plant species of Europe. We assume this
sample can be taken as represent ative of the responses of
European plant species to climate change because it includes
most of the life forms and phytogeographic patterns found
among plant species in Europe.
Climate data were obtained from the Climatic Research Unit
( and included mean annual, winter, and
summer precipitation, mean annual temperature and minimum
temperature of the coldest month (MTC), growing deg ree days
(5°) and an index of moisture availability (22). These variables
were chosen because of their strong link with the physiology and
growth of plant species (23, 24). For instance, MTC discrimi-
nates species based on their ability to assimilate soil water and
nutrients, and continue cell div ision, differentiation and tissue
growth at low temperatures (lower limit), and chilling require-
ments for processes such as bud break and seed germination
(upper limit). The moisture index discriminates species through
This paper was submitted directly (Track II) to the PNAS office.
Freely available online through the PNAS open access option.
Abbreviation: IUCN, International Union for Conservation of Nature and Natural
To whom correspondence should be addressed. E-mail:
© 2005 by The National Academy of Sciences of the USA
www.pnas.orgcgidoi10.1073pnas.0409902102 PNAS
June 7, 2005
vol. 102
no. 23
processes related to phenology, rooting strateg y, leaf morphol-
ogy, and xylem vulnerability to cavit ation. However, because
there is surprisingly little experiment al work for any particular
species to guide the choice of bioclimatically limiting variables,
the variables are generic and represent a hypothetical minimum
basic set for n iche-based modeling. Climate dat a were averaged
for the 1961–1990 period. The data were supplied on a 10-foot
(1 f t 0.3 m) grid covering Europe. They were aggregated by
averaging to 50 50 km Universal Transverse Mercator (UTM)
to match the species data grid. Niche-based models were cali-
brated on the 50 50 km UTM grid, and modeled species
distributions were projected back onto the 10 grid for current
and future climate.
Future projections were derived by using climate model
outputs made available through the Intergovernmental Panel on
Climate Change (IPCC) Data Distribution Centre (ipcc-ddc.cru.
The modeled climate anomalies were scaled based
on four scenarios proposed by the IPCC (12). The A1 scenario
describes a globalized world with rapid economic growth and
global population that peaks in mid-century and declines there-
af ter and assumes rapid introduction of new and more efficient
technologies. Concentrations of CO
increase from 380 ppm in
2000 to 800 ppm in 2080, and temperature rises by 3.6 K (12). The
A2 scenario describes a heterogeneous world with regionally
oriented economic development. Per capita ec onomic g rowth
and technological change are slower than in the other scenarios.
Global concentrations of CO
increase from 380 ppm in 2000 to
700 ppm in 2080, and temperature rises by 2.8 K. The B1 scenario
describes a convergent world with global population that peaks
in mid-century and declines thereafter, as in A1, but with a rapid
change toward a service and information economy and the
introduction of clean and resource-ef ficient technology. Con-
centrations of CO
increase from 380 ppm in 2000 to 520 ppm
in 2080, and temperature rises by 1.8 K. The B2 scenario
describes a world in which the emphasis is on local solutions to
socioec onomic and environment al sustainability. It is a world
with continuously increasing global population (at a rate lower
than A2), intermediate levels of economic development, and less
rapid and more diverse technological change than in the B1 and
A1 scenarios. Concentrations of CO
increase from 380 ppm in
2000 to 550 ppm in 2080, and temperature rises by 2.1 K (12).
We did not assess the impacts of land-use change, even though
this factor will potentially compound the effects of climate
change on species distributions (25). However, given the spatial
extent and resolution of our data and the magnitude of climate
change in most projections, the effect of land use would be most
likely overridden by climate (26, 27).
Niche-Based Models of Species Climatic Envelops. We used the
BIOMOD framework, which capitalizes on several widely used
n iche-based modeling techniques (generalized linear models,
generalized additive models, classification tree analysis, and
artificial neural net works) to provide alternative spatial projec-
tions (13). For each climate change scenario, models relating
species distributions to the seven bioclimatic variables were fitted
by using BIOMOD and projected into the future. Then, a consen-
sus principal component analysis was run to explore central
tendencies in projections and select the niche-based model
representing the greatest commonality among projections (8).
There is increasing evidence that model projections can be
extremely variable, and there remains a need to test the
ac curac y of models and to reduce uncertainties (8, 28, 29). One
recent analysis has however provided the first test of the
predictive accurac y of such models by using bird observed
species’ range shifts and climate change in two periods of the
recent past (30). This work provides validation of niche-based
models under climate change and demonstrated how uncer-
t aint y can be reduced by selecting the most consensual pro-
jections, as done in this study. We are therefore confident that
this strateg y prov ides a robust and defensible approach to
species range projections for the purposes of c onservation
plann ing and biodiversit y management.
To evaluate species extinction risks, we summed the number
of pixels lost, potentially gained (under universal mig ration), or
st able by each species for the different climate-change scenarios.
We assigned each species to an International Un ion for Con-
servation of Nature and Natural Resources (IUCN) threat
category (IUCN 2001). Those that were not listed were classified
as lower risk, depending on the projected reduction in range size
f rom present to 2080. Present and future range sizes (area of
oc cupancy) were estimated f rom the number of pixels where
species occurred. Loss in range size was calculated by subtracting
future potential range size from present potential range size. In
line with IUCN Red List criterion A3(c), the following thresh-
olds were then used to assign a species to a threat category
(IUCN 2001). Extinct is a species with a projected range loss of
100% in 50 or 80 years, critically endangered has a projected
range loss of 80%, endangered has a projected range loss of
50%, and vulnerable has a projected range loss of 30%.
A lthough this Red Listing approach is simplistic and c onsiders
only the effects of climate change, it provides a synthetic
overview of species-specific threats due to climate change.
To evaluate the percentage of extinctions for a given area, we
summed the number of species lost (L) by pixel and related it to
current species richness by pixel. The procedure was the same to
assess the percentage of species gained (G) by pixel (under
assumptions that species could reach a new suitable climate
space). Percent age of species turnover by pixel, under the
assumption of universal migration, is then given by T 100
(L G)(SR G) where SR is the current species richness.
Results and Discussion
Many European species could be threatened by future climate
change (Fig. 1). Under the assumption of no migration, more
than half of the species we considered become vulnerable or
c ommitted to extinction by 2080. The impacts of climate change
are, naturally, less under the universal migration because of the
possibilit y for species to move across landscapes. Under the
no-migration assumption and the most severe climate change
scenario (A1-HadCM3), 22% of the species become critically
endangered (80% range loss), and 2% extinct by 2080. These
numbers decrease for the other scenarios and climate models.
Under the universal migration assumption, the results are, as
ex pected, less severe. Under tA1-HadCM3, 67% of species
would be classified as low risk, whereas under B1-HadCM3, 76%
of the species would be at low risk.
Our results coincide with the direction of predictions made by
Thomas et al. (11), although the magnitude of the risks we
project is less [and note that we project distributions to 2080,
whereas Thomas et al. (11) only projected to 2050].
Niche-based modeling does not address the proximate causes
of species extinction. Nevertheless, any reduction in the potential
geographic range of a species is likely to lead to an increased risk
of local extinction (11). This conclusion is, in fact, the rationale
for building IUCN Red Lists (31). A decrease in range size
implies that smaller stochastic events af fect a larger proportion
of the species’ total population, especially in fragmented land-
scapes. If a species becomes restricted to a few sites, then local
cat astrophic events (such as droughts or disease outbreaks) or an
Mitchell, T. D., Carter, T. R., Jones, P. D., Hulme, M. & New, M. (2004) A Comprehensive
Set of High-Resolution Grids of Monthly Climate for Europe and the Globe: The Observed
Record (1901–2000) and 16 Scenarios (2001–2100) (Tyndall Centre for Climate Change
Res., Norwich, U.K.), Working Paper 55.
www.pnas.orgcgidoi10.1073pnas.0409902102 Thuiller et al.
increase of land transformation by humans c ould easily cause the
extinction of that species (32).
Rates of species’ loss and turnover show great variation across
scenarios (Fig. 2). In A1-HadCM3, the mean European temper-
ature increases by up to 4.4 K, leading to a mean species loss of
42% and turnover of 63%. This scenario provides the widest
range of variability across Europe for both species loss (2.5–
86%) and turnover (22–90%). The percentage of species loss
c ould exceed 80% in some areas, such as northcentral Spain and
the Cevennes and Massif Central in France. B1-HadCM3 gives
the lowest expected mean percentage of species loss (27%),
reflecting the fact that this scenario has the lowest rate of
increase in CO
and temperature by 2080 (mean European
temperature increase of 2.7 K). Other scenarios show interme-
diate mean rates of species loss (30%) and turnover (50%).
The relationship between the modeled percent age of species
loss and the anomalies for the two most significantly correlated
bioclimatic variables, growing-degree days (representing ac cu-
mulated warmth) and a moisture availability index, was used to
unc over the potential causes of variations in predicted changes
in plant diversity across regions within and across scenarios (Fig.
3). The strong consistent linear relationship across scenarios
indicates that projected species loss from our models could be
estimated f rom these two predictors. The Spearman rank-
c orrelation values for the separate univariate relationships were
0.73 and 0.65, respectively. Multiple-linear regression by using
these two predictors explains 60% of the variance across sce-
narios. The temperature of the coldest month, although being an
import ant predictor of distributions for many species (6), did not
show a strong relationship with species loss overall and was
therefore not used in this analysis.
Regional deviations from the inferred relationship (positive
and negative residuals) can be interpreted as indications of
particularly high or low species vulnerability, because of ecolog-
Fig. 1. Proportion of species classified according to the IUCN Red List assessment under two extremes assumptions about species migration. EX, extinct; CR,
critically endangered; EN, endangered; VU, vulnerable; LR, lower risk.
Fig. 2. Estimated percentage of species loss and turnover. Upper extreme, upper quartile, median, lower quartile, and lower extreme are represented for each
Thuiller et al. PNAS
June 7, 2005
vol. 102
no. 23
ical and historical characteristics of the flora, andor specific
environment al conditions (Fig. 4). An excess of species loss (red
c olor) is shown for mount ain regions (mid-altitude Alps, mid-
altitude Pyrenees, central Spain, French Cevennes, Balkans,
Carpathians). Severe climatic conditions have occurred in moun-
t ains over evolutionary times, promoting highly specialized
species with strong adaptation to the limited opportunities for
growth and survival (33). The narrow habitat tolerances of the
mount ain flora, in conjunction with marginal habitats for many
species, are likely to promote higher rates of species loss for a
similar climate anomaly than in any other part of Europe (34).
By contrast, the southern Mediterranean and part of the Pan-
non ian regions have a negative residual for species loss (gray
c olor). Both regions are characterized by hot and dry summers
and are occupied by species that tolerate strong heat and
drought. Under the scenarios used here, these species are likely
to continue to be well adapted to future conditions.
We finally present mean percentages of species loss and
turnover by environmental zones (M. Metzger, unpublished
dat a) with the A1-HadCM3 scenario of maximum change to best
illustrate the spatial patterns (Fig. 5). The major spatial patterns
are similar over all scenarios. The northern Mediterranean
(52%), Lusitanian (60%) and Mediterranean mount ain (62%)
regions are the most sensitive regions; the Boreal (29%), north-
ern Alpine (25%), and Atlantic (31%) regions are consistently
less sensitive. Species turnover shows a somewhat different
pattern. The Boreal region could, in principle, gain many species
f rom further south, leading to a high species turnover (66%). The
Pannon ian region c ould also theoretically gain eastern Mediter-
ranean species and has a calculated turnover of 66%. Thus, these
regions stand to lose a substantial part of their plant species
diversit y, and (in time) to show a major change in floristic
c omposition. Projected species turnover peaks at the transition
bet ween the Mediterranean and continental regions (Fig. 5) with
extirpation of Euro-Siberian species and expansion for Medi-
terranean or Atlantic species. Southern Fennoscandia is also an
area of high potential turnover w ith the loss of boreal species and
gain of Euro-Siberian species.
These results cannot be taken as precise forecasts given the
uncert ainties in climate change scenarios, the coarse spatial
resolution of the analysis (35), and uncertainties in the mod-
eling techniques used (8, 29). The relatively coarse grid scale
of our study may hide potential refuges for species and
env ironmental heterogeneit y that c ould enhance species sur-
v ival, especially in mountain areas where our estimation of
risks of extinctions c ould be overestimated. On the other hand,
landscape f ragmentation c ould increase the vulnerability of
these refuges to fire or other disturbances, which in c ombina-
tion with the lack of propagule flow, c ould compromise the
survival of remnant populations. There are also major uncer-
t ainties due to lags associated w ith biotic processes. The
rec ogn ized time scales for assign ing species IUCN Red List
categories are not suited to evaluating the c onsequences of
slow-acting but persistent threats. We have substituted a time
scale of 80 years (instead of 20) for critically endangered,
endangered and vulnerable, respectively, over which to assess
Fig. 3. Relationships between the percentage of species loss and anomalies of moisture availability and growing-degree days.The colors correspond to different
climate change scenarios.
Fig. 4. Regional projections of the residuals from the multiple regression of
species loss against growing-degree days and moisture availability. Red colors
indicate an excess of species loss; gray colors indicate a deficit.
www.pnas.orgcgidoi10.1073pnas.0409902102 Thuiller et al.
declines. The extent of species losses may be overestimated,
because the plasticity of species and the survival of species in
favorable microhabitats is not considered. However, even if
the numbers are overestimated, patterns across regions may
st and (e.g., the rank ing of region in ter ms of vulnerabilit y to
loss). Species loss does not necessarily imply the immediate
loss of a species f rom a site, rather it may imply a potential lack
of reproductive success and recruitment that w ill tend to
extinction on a longer time scale (36). Mig ration rates are
likely to be species-specific, and resulting biotic interactions in
‘‘no-analogue’’ assemblages may alter species’ realized n iches.
L and use and associated habitat fragmentation are likely to
generally inhibit mig ration rates (19). Further, future species
distributions w ill likely be influenced by other environmental
factors than changing climate. The current atmospheric CO
c oncentration exceeds any experienced during the past 20 mil-
lion years (12). Plant physiological responses, including grow th
responses to increased atmospheric CO
and changes in water-
use efficienc y, are expected to ameliorate the response of some
plant functional types to climate change (37). On the other hand,
n itrogen deposition, the enhanced potential for invasion by
exotic species, or the promotion of more competitive native
species may change competitive interactions in plant commun i-
ties, yielding novel patterns of dominance and ecosystem
function (38).
Despite uncert ainties, our findings provide illustration of the
potential importance and the likely direction of climate change
ef fects. From a conservation perspective, a proportion of Eu-
ropean plant species c ould become vulnerable. The strong
positive relationship between projected species loss and changes
in bioclimatic variables implies that action to reduce greenhouse
gas emissions would also mitigate climate-change effects on
plant diversit y. However, even under the least severe scenario
c onsidered, the risks to biodiversity appear to be considerable.
Dif ferent regions are ex pected to respond differently to climate
change, with the greatest vulnerability in mountain regions and
the least in the southern Mediterranean and Pannonian regions.
Recent observations (39) and predictions (9) corroborate our
c onclusion regarding the climatic sensitivity of species in Euro-
pean mountain areas. We have also identified a broad transition
zone where the greatest species mixing is likely to occur. During
the Quaternary period, this region acted both as a crossing point
and a refuge zone for Boreo-alpine and Euro-Siberian species
(40). This transition zone will be a strategic region for plant-
species conservation in a changing climate.
M.B.A. thanks T. Lathi and R. Lampinen for providing a digital version
of Atlas Florae Europaeae. We thank M. Erhard (Potsdam-Institute for
Climate Impact Research, Potsdam, Germany) for repackaging and
aggregating original climate data into the Atlas Florae Europaeae g rid
and M. Metzger for his environmental classification of Europe. This
research was funded by the integrated projects of the European Com-
mission’s FP5 Advanced Terrestrial Ecosystem Analysis and Modeling
(EVK2-CT-2000-00075) and FP6 Assessing Large-Scale Env ironmental
Risks with Tested Methods (GOCE-CT-2003-506675).
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... Yine aşırı yağışlar çiçeklerdeki nektarı seyreltmekte veya yıkamakta ve dolayısı ile bal arısı bu nektardan yararlanamamaktadır. Bu iki durumun aşırı seyretmesi durumunda bal arısı kolonisi açlık tehlikesi ile karşı karşıya kalmakta ve yine yetiştirici tarafından destesteklenmez ise kolonilerin ölümü ile sonuçlanabilmektedir. Dolayısı ile iklim, kolonilerin besin madde ihtiyacını karşılamak için ihtiyaç duyduyu nektar ve polenin üretildiği çiçekli bitkiler üzerinde doğrudan etkilidir (Winston, 1987;Thuiller, 2005). Polen üretimini azaltan veya durduran ve kalitesinin bozulmasına neden olan aşırı kuraklık, bal arısının protein ihtiyacını karşılayamamasına neden olmaktadır. ...
... Climate change is expected to modify community composition through variation in the rates of species' range shifts (10), through the appearance of novel climate types (11), as a consequence of local extinctions and/or colonizations (12), and through species' abundance distribution changes (3). Alterations in community composition are relevant in the context of ecosystem functioning under global change: ecological communities are more than the mere sum of their species because interspeci c interactions shape communities' functionality (13). ...
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Species’ range shifts and local extinctions caused by climate change lead to community composition changes. At large spatial scales, ecological barriers, such as biome boundaries, coastlines, and elevation, can influence a community's ability to shift in response to climate change. Yet, ecological barriers are rarely considered in climate change studies, potentially hindering predictions of biodiversity shifts. We used data from two consecutive European breeding bird atlases to calculate the geographic distance and direction between communities in the 1980's and their compositional best match in the 2010’s and modeled their response to barriers. The ecological barriers affected both the distance and direction of bird community composition shifts, with coastlines and elevation having the strongest influence. Our results underscore the relevance of combining ecological barriers and community shift projections for identifying the forces hindering community adjustments under global change. Notably, due to (macro)ecological barriers, communities are not able to track their climatic niches, which may lead to drastic changes, and potential losses, in community compositions in the future.
... Alpine habitats are very important biodiversity hotspots with many relict and endemic species [1,2]. Alpine species are adapted to specific habitats and environmental conditions (montane meadows and pastures with specific climatic conditions such as short summers and long winters), but they are very sensitive to anthropogenic impacts (mass tourism, afforestation and deforestation, damming and channelisation of alpine rivers, and development of ski centres and road infrastructure) and especially to climate change [3][4][5][6][7]. The influence of negative factors in alpine habitats has been studied mainly on flora [5,8,9], but animals with small home ranges and low dispersal ability, such as amphibians and reptiles, can also be good bioindicators of environmental health [10]. ...
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Alpine habitats are exposed to increasing anthropogenic pressure and climate change. The negative impacts can lead to chronic stress that can affect the survival and reproductive success of individuals and even lead to population extinction. In this study, we analyse different morphological and ecological traits and indices of abiotic and biotic stressors (such as head size and shape, fluctuating asymmetry, body condition index, tail autotomy, and population abundance) in alpine and subalpine populations of two lacertid species (Zootoca vivipara and Lacerta agilis) from Serbia and North Macedonia. These lizards live under different conditions: allotopy/syntopy, different anthropogenic pressure, and different levels of habitat protection. We found differences between syntopic and allotopic populations in pileus size, body condition index (in both species), pileus shape, fluctuating asymmetry (in L. agilis), and abundance (in Z. vivipara). Differences between populations under anthropogenic pressure and populations without it were observed in pileus shape, body condition index (in both species), pileus size, fluctuating asymmetry, tail autotomy and abundance (in L. agilis). On the basis of our results, it is necessary to include other stress indicators in addition to fluctuating asymmetry to quickly observe and quantify the negative effects of threat factors and apply protective measures.
... However, species that have restricted distributions and/or greater sensitivity to environmental disturbances may not find new habitats that are suitable for them in the future, thus becoming more vulnerable and are at greater risk of extinction (Ruegg et al. 2021). In particular, stochastic and local disturbance events, such as droughts, disease outbreaks, and land use changes, may accelerate the extinction of species with smaller distribution ranges (Thuiller et al. 2005;Lawton 1995). In both cases -range shift and extinction -can lead to changes in the composition of local and regional communities, and might result in generalists and more tolerant species numbers to increase compared to more sensitive species (Baselga 2010;Spaak et al. 2017;Hidasi-neto et al. 2019;Mota et al. 2022). ...
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Climatic niches are key factors driving global and regional species distributions. The Atlantic Forest domain is considered one of the most threatened biomes in the world, and one of the main centres of plant diversity and endemism in the Neotropics. Of the over 13,000 species of vascular plants, nearly 15% are vascular epiphytes. Here we analysed for the first time how current epiphyte niches will be affected under future climate projections (SSP126 and SSP585) within 1.5 million km2 of Atlantic Forest in South America. Using the largest database of vascular epiphytes to date (n = 1521 species; n = 75,599 occurrence records) and ordination models, we found that the Atlantic Forest is expected to become warmer and drier and that up to 304 epiphyte species (20%) will have their average niche positions displaced outside the available climate space by the years 2040–2100. The findings from this study can help to inform ongoing legislative conservation efforts in one of the world’s most biodiverse regions.
... As for changes in microclimatic conditions, mainly in cold ecosystems (e.g., mountains or Patagonia), changes in temperature and soil moisture contribute significantly to the loss of native plants [33]. Our results are consistent with experimental studies of temperature manipulation indicating that native plant richness locally decreases with increasing soil temperature, especially in cold ecosystems [34]. ...
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Citation: García, R.A.; Fuentes-Lillo, E.; Cavieres, L.; Cóbar-Carranza, A.J.; Davis, K.T.; Naour, M.; Núñez, M.A.; Maxwell, B.D.; Lembrechts, J.J.; Pauchard, A. Pinus contorta Alters Microenvironmental Conditions and Reduces Plant Diversity in Patagonian Ecosystems. Diversity 2023, 15, 320. https://doi. Abstract: Pinus contorta is considered one of the most invasive tree species worldwide, generating significant impacts on biodiversity and ecosystems. In several Patagonian ecosystems in southern Chile, it has escaped from plantations established mainly in the 1970s, and is now invading both forests and treeless environments. In this study, we evaluated the impact of the invasion of P. contorta on microenvironmental conditions in Araucaria araucana forest and Patagonian steppe ecosystems, and assessed how these changes related to the richness and abundance of native and non-native plant species. In each ecosystem, 24 plots of 100 m 2 were established along a gradient of P. contorta biomass, where 18 environmental variables and the composition of native and non-native vegetation were measured at a local scale. Our results indicated that increased pine biomass was associated with differences in microclimatic conditions (soil and air temperature, photosynthetically active radiation (PAR), and soil moisture) and soil properties (potassium, nitrate, pH, and litter accumulation). These changes were ecosystem dependent, however, as well as associated with the level of invasion. Finally, the reduction in the richness and abundance of native plants was associated with the changes in soil properties (accumulation of leaf litter, pH, and organic matter) as well as in the microclimate (minimum air temperature, PAR) generated by the invasion of P. contorta. Overall, our results confirm that the invasion of P. contorta impacts microenvironmental conditions (i.e., canopy cover, litter accumulation, minimum air temperature, and maximum soil temperature) and reduces native plant diversity. For future restoration plans, more emphasis should be given to how environmental changes can influence the recovery of invaded ecosystems even after the removal of the living pine biomass (i.e., legacy of the invasion).
... Against the backdrop of climate aridization (especially with the appearance of long dry periods), the safety of forest belts began to deteriorate sharply. The possibility of growing trees and shrubs under such conditions is limited by a number of factors (Allen, et al., 2010;Bertrand et al., 2011;Chang et al., 2015;Manaenkov, 2017;Repo et al., 2021;Thuiller et al., 2005) including precipitation. Creating the necessary conditions for moisture accumulation in forest belts can provide these areas with an additional supply of moisture. ...
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The Journal of Agrometeorology (JAM) with ISSN 0972-1665 (print) and 2583-2980 (online), is an Open Access quarterly publication of Association of Agrometeorologists, Anand, Gujarat, India, appearing in March, June, September and December.
The subalpine zone of the Himalaya epitomises a transition (ecotone) between alpine grassland and temperate forest ecosystems. This research was conducted in seven sites Chanshal, Marhi, Chotabanghal, Hattu, Shipkila, Jot, and Pangi Valley of Himachal Pradesh. A total of 61 species of butterflies belonging to 45 genera, 5 families, and 16 subfamilies were documented. The members of the family Papilionidae and Hesperiidae have been least recorded. We have carried out butterfly sampling along an elevational gradient (2300–3899 m). A Kruskal Wallis test for diversity indices for seven different sites from the year 2013 to 2015 (H = 1.024, df = 6 p = 0.984, H = 0.642 df = 6 p = 0.995, H = 0.690 df = 6 p = 0.994 p > 0.05) revealed no significant difference. Three species legally protected under Wildlife Protection Act, India, 1972, have been detected. They are Lampides boeticus, Maniola devendra devendra Schedule II Part II and Euploea mulciber Schedule IV.
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Today, climate change affects all living things on earth. It also leads to serious losses in terms of biodiversity, ecosystem services, and human welfare. In this context, Laurus nobilis L. is a very important species for Turkey, and the Mediterranean countries. This research aimed to simulate the current distribution of the suitable habitat for L. nobilis in Turkey and to predict its possible range shifts in future climate scenarios. To predict the geographical distribution of L. nobilis, the study used the maximum -entropy algorithm-based MaxEnt 3.4.1 with seven bioclimatic variables created using the Community Climate System Model 4.0 (CCSM4) and the prediction models RCP4.5-8.5 for the years 2050-2070. The results indicated that the most important bioclimatic variables that shape the distribution of L. nobilis are BIO11-mean temperature of coldest quarter, and BIO7-annual temperature range. Two climate change scenarios predicted that the geographical distribution of L. nobilis would increase slightly and then decrease in the future. However, the spatial change analysis showed that the general geographical distribution area of L. nobilis did not change significantly , but the "moderate," "high," and "very high" suitable habitats changed towards "low" suitable habitats. These changes were particularly effective in Turkey's Mediterranean region, which shows that climate change is instrumental in determining the future of the Mediterranean ecosystem. Therefore, suitabil-ity mapping and change analysis of potential future bioclimatic habitats can help in planning for land use, conservation, and ecological restoration of L. nobilis.
Climate change is affecting biodiversity at an accelerating rate. Despite the importance of fungi in ecosystems in general, and in the global carbon and nitrogen cycle in particular, there is little research on the response of fungi to climate change compared with plants and animals. Earlier studies show that climatic factors and tree species are key determinants of macrofungal diversity and distribution at large spatial scales. However, our knowledge of how climate change will affect macrofungal diversity and distribution in the future remains poorly understood. Europe. Using openly available occurrence data of 1845 macrofungal species from eight European countries (i.e. Norway, Sweden, Finland, Denmark, Netherlands, Germany, France and Spain), we built ensemble species distribution models to predict macrofungal response to climate change alone and combined climate and tree distribution change under the IPCC special report on 2080 emissions scenarios (SRES A2 and B2). Considering climate change alone, we predict that about 77% (74.1%–80.7%) of the modelled species will expand their distribution range, and around 57% (56.1%–58.4%) of the modelled area will have an increase in macrofungal species richness. However, when considering the combined climate and tree species distribution change, only 50% (50%–50.9%) of the species are predicted to expand their distribution range and 49% (47.4%–51.1%) of the modelled area will experience an increase in macrofungal species richness. Overall, our models projected that large areas would exhibit increased macrofungal species richness under future climate change. However, tree species distribution might play a restrictive role in the future distributional shifts of macrofungi. In addition, macrofungal responses appear heterogeneous, varying among species and regions. Our findings highlight the importance of including tree species in the projection of climate change impacts on the macrofungal diversity and distribution on a continental scale.
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Theory predicts low niche differentiation between species over evolutionary time scales, but little empirical evidence is available. Reciprocal geographic predictions based on ecological niche models of sister taxon pairs of birds, mammals, and butterflies in southern Mexico indicate niche conservatism over several million years of independent evolution (between putative sister taxon pairs) but little conservatism at the level of families. Niche conservatism over such time scales indicates that speciation takes place in geographic, not ecological, dimensions and that ecological differences evolve later.
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A new computation framework (BIOMOD: BIOdiversity MODelling) is presented, which aims to maximize the predictive accuracy of current species distributions and the reliability of future potential distributions using different types of statistical modelling methods. BIOMOD capitalizes on the different techniques used in static modelling to provide spatial predictions. It computes, for each species and in the same package, the four most widely used modelling techniques in species predictions, namely Generalized Linear Models (GLM), Generalized Additive Models (GAM), Classification and Regression Tree analysis (CART) and Artificial Neural Networks (ANN). BIOMOD was applied to 61 species of trees in Europe using climatic quantities as explanatory variables of current distributions. On average, all the different modelling methods yielded very good agreement between observed and predicted distributions. However, the relative performance of different techniques was idiosyncratic across species, suggesting that the most accurate model varies between species. The results of this evaluation also highlight that slight differences between current predictions from different modelling techniques are exacerbated in future projections. Therefore, it is difficult to assess the reliability of alternative projections without validation techniques or expert opinion. It is concluded that rather than using a single modelling technique to predict the distribution of several species, it would be more reliable to use a framework assessing different models for each species and selecting the most accurate one using both evaluation methods and expert knowledge.
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Abstract Although bioclimatic modelling is often used to estimate potential impacts of likely climate changes, little has been done to assess the reliability and variability of projections. Here, using four niche-based models, two methods to derive probability values from models into presence–absence data and five climate change scenarios, I project the future potential habitats of 1350 European plant species for 2050. All 40 different projections of species turnover across Europe suggested high potential species turnover (up to 70%) in response to climate change. However variability in the potential distributional changes of species across climate scenarios was obscured by a strong variability in projections arising from alternative, yet equally justifiable, niche-based models. Therefore, projections of future species distributions and derived community descriptors cannot be reliably discussed unless model uncertainty is quantified explicitly. I propose and test an alternative way to account for modelling variability when deriving estimates of species turnover (with and without dispersal) according to a range of climate change scenarios representing various socio-economic futures.
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A model to predict global patterns in vegetation physiognomy was developed from physiological considerations influencing the distributions of different functional types of plant. Primary driving variables are mean coldest-month temperature, annual accumulated temperature over 5-degrees-C, and a drought index incorporating the seasonality of precipitation and the available water capacity of the soil. The model predicts which plant types can occur in a given environment, and selects the potentially dominant types from among them. Biomes arise as combinations of dominant types. Global environmental data were supplied as monthly means of temperature, precipitation and sunshine (interpolated to a global 0.5-degrees grid, with a lapse-rate correction) and soil texture class. The resulting predictions of global vegetation patterns were in good agreement with the mapped distribution of actual ecosystem complexes (Olson, J.S., Watts, J.A. & Allison, L.J. (1983) ORNL-5862, Oak Ridge Nat. Lab., 164 pp.), except where intensive agriculture has obliterated the natural patterns. The model will help in assessing impacts of future climate changes on potential natural vegetation patterns, land-surface characteristics and terrestrial carbon storage, and in analysis of the effects of past climate change on these variables.
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The responsiveness of South African fauna to climate change events is poorly documented and not routinely incorporated into regional conservation planning. We model the likely range alterations of a representative suite of 179 animal species to climate change brought about by the doubling of CO2 concentrations. This scenario is expected to cause a mean temperature increase of 2 °C. We applied a multivariate climate envelope approach and evaluated model performance using the most comprehensive bird data set. The results were encouraging, although model performance was inconsistent in the eastern coastal area of the country. The levels of climate change induced impacts on species ranges varied from little impact to local extinction. Some 17% of species expanded their ranges, 78% displayed range contraction (4–98%), 3% showed no response and 2% became locally extinct. The majority of range shifts (41%) were in an easterly direction, reflecting the east–west aridity gradient across the country. Species losses were highest in the west. Substantially smaller westward shifts were present in some eastern species. This may reflect a response to the strong altitudinal gradient in this region, or may be a model artifact. Species range change (composite measure reflecting range contraction and displacement) identified selected species that could act as climate change indicator taxa. Red-data and vulnerable species showed similar responses but were more likely to display range change (58% vs. 43% for all species). Predictions suggest that the flagship, Kruger National Park conservation area may loose up to 66% of the species included in this analysis. This highlights the extent of the predicted range shifts, and indicates why conflicts between conservation and other land uses are likely to escalate under conditions of climate change.
It is hypothesized that the principal features of higher plant distributions at continental scales are determined by the macroclimate. Bioclimate data have been computed on a 50 km grid across Europe. Along with published maps of higher plant distributions based upon the same grid, these data have been used to derive climate response surfaces that model the relationship between a species' distribution and the present climate. Eight species representative of a variety of phytogeographic patterns have been investigated. The results support the hypothesis that the European distributions of all eight species are principally determined by macroclimate and illustrate the nature of the climatic constraints upon each species. Simulated future distributions in equilibrium with 2× CO2 climate scenarios derived from two alternative GCMs show that all of the species are likely to experience major shifts in their potential range if such climatic changes take place. Some species may suffer substantial range and population reductions and others may face the threat of extinction. The rate of the forecast climate changes is such that few, if any, species may be able to maintain their ranges in equilibrium with the changing climate. In consequence, the transient impacts upon ecosystems will be varied but often may lead to a period of dominance by opportunist, early-successional species. Our simulations of potential ranges take no account of such factors as photoperiod or the direct effects of CO2, both of which may substantially alter the realized future equilibrium.
. The relationship between present climate and the distribution in Europe of the aggressively invasive exotic Fallopia japonica is described by fitting a response surface based on three bioclimatic variables: mean temperature of the coldest month, the annual temperature sum > 5 °C, and the ratio of actual to potential evapotranspiration. The close fit between the observed and simulated distributions suggests that the species' European distribution is climatically determined. The response surface also provides a simulation of the extent of the area of native distribution of F. japonica in Southeast Asia that is generally accurate, confirming the robustness of the static correlative model upon which it is based. Simulations of the potential distribution of F. japonica under two alternative 2 x CO2 climate change scenarios indicate the likelihood of considerable spread into higher latitudes and possible eventual exclusion of the species from central Europe. However, despite the robustness of the response surface with present-day climate, the reliability of these simulations as forecasts is likely to be limited because no account is taken of the direct effects of CO2 and their interaction with the species' physiological responses to climate. Similarly, no account is taken of the potential impact of interactions with ‘new’ species as ecosystems change in composition in response to climate change. Nevertheless, the simulations indicate both the possible magnitude of the impacts of forecast climate changes and the regions that may be susceptible to invasion by F. japonica.
Ecological response surfaces are nonlinear functions describing the way in which the abundances of taxa depend on the joint effects of = or >2 environmental variables. Continental-scale patterns in the relative abundances of plant taxa are dominated by the effects of macroclimate on the competive balance among taxa. Pollen analyses record such regional variations for major vegetation components. Empirical ecological response surfaces were derived from high-resolution climate models to yield testable reconstructions of vegetation in E North America. Response surface analysis consists of a remapping of abundance patterns from geographic space into climate space, and complements efforts to explain distributions in terms of biological processes. The surfaces focus attention on the climatic location of range limits and optima, and on less obvious phenomena such as the spatial pattern in the relative sensitivity of different taxa to spatial variation in the climatic variables. Such response surfaces may be coupled to palaeoclimatic simulations from high-resolution climate models to yield testable reconstructions of vegetational history.-from Authors