Biodiversity Adaptation to Climate change in the ECA region

30 Pages·2009·12.72 MB·English

Nicola Cenacchi
Draft, June 2008

Biodiversity Adaptation to Climate change in the
ECA region.
A contribute to the Umbrella Report on adaptation to
climate change in ECA

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Table of Contents

1. INTRODUCTION..................................................................................................................................................3
1.1 GENERAL CLIMATE CHANGE EFFECTS ON BIODIVERSITY IN ECA.......................................................................3
1.1.1 Biodiversity in ECA...................................................................................................................................3
1.1.2 Changing averages – range shift, extinctions, phenology.........................................................................7
1.1.3 Extreme events- droughts, floods...............................................................................................................7
2. ADAPTATION FOR BIODIVERSITY...............................................................................................................9
2.1 FRAMING THE BIODIVERSITY QUESTION.............................................................................................................9
2.2 REGIONAL AND GLOBAL ADAPTATION EFFORTS..............................................................................................12
2.2.1 Protected areas........................................................................................................................................12
2.2.2 Adaptation should hinge on a landscape approach.................................................................................13
3. ADAPTATIONS BY BIOME.............................................................................................................................16
3.1 GRASSLANDS...................................................................................................................................................18
3.2 FORESTS...........................................................................................................................................................20
3.2.1 Temperate and Mediterranean forests.....................................................................................................20
3.2.2 Boreal forests..........................................................................................................................................20
3.2.3 On adaptation practices..........................................................................................................................21
3.3 ALPINE/MONTANE ECOSYSTEMS......................................................................................................................22
3.4 ARCTIC ECOSYSTEMS.......................................................................................................................................23
3.5 FRESHWATER AREAS........................................................................................................................................24
4. CONCLUSION – CHALLENGES FOR ADAPTIVE CAPACITY IN ECA.................................................28
5. REFERENCES.....................................................................................................................................................29

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1. Introduction

1.1 General climate change effects on Biodiversity in ECA

1.1.1 Biodiversity in ECA

Because of its vast expanse, the ECA region “includes the world’s largest contiguous steppe and
intact forest ecosystems….. and 21 mountain chains” (Brylski and Abdulin 2003), it spans over
nine major biomes (out of a total of 151) and contains nearly 100 different ecoregions (Figure 1).
It contains 26 of the WWF global 200 priority areas (i.e. 13% of the total; Figure 2), and it
includes parts or the total of three biodiversity hotspots regions: the Mediterranean basin, the
Caucasus and the Mountains of Central Asia (BOX 1).

Biodiversity is the source of ecosystem goods and services. These services (Figure 3) are not
determined by the shear richness in species, but rather they depend on species composition, on
the functional elements of an ecosystem. In providing services some species have a more critical
role than others; some species may be substituted because functionally redundant (a trait that
informs of the resiliency of an ecosystem), and local extinctions do more harm when they wipe
out or seriously damage an entire functional guild.

Given that climate change, both in terms of changing climatic averages and extreme events, will
have different impacts on ecosystems within ECA, it is critical to understand better what the
effects may be, and what solutions could be chosen to reduce the magnitude of the impacts.

BOX 1 Hotspots and Priority areas

The WWF 200 Global priority areas are a set of ecoregions chosen as the areas where conservation efforts and
resources should be concentrated. The rationale behind the choice resides in the high level of species richness and
endemism of these ecoregions; also, they are chosen as representative of the world’s biomes on different continents
or ocean basins (Olson and Dinerstein 2002)

Hotspots are areas “featuring exceptional concentrations of endemic species and experiencing exceptional loss of
habitat” (Myers et al. 2000). The focus on these hotspots has been identified by conservationists as another
approach to stop the high rates of extinction.

1 The only Biomes not represented are the tropical biomes and mangroves .
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Figure 3. ecosystem services, relation with biodiversity and interaction
with global changes

Source: Millenium ecosystem assessment

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1.1.2 Changing averages – range shift, extinctions, phenology

The IPCC 4th assessment report project that climate change is likely to put at risk 50% of the
biodiversity of all Asia (Cruz et al. 2007) . Average annual temperatures are expected to
increase up to between 1.6º and 2.6º degrees by 2050 (see Climate Science Section2), with most
of the warming taking place in the winter for the north and eastern parts of ECA, and in the
summer for the southern regions (see Figure 9 & 10 Climate Science Section).

The first impact of these changes will be a modification of species’ ranges (and therefore of
ecosystems’ location). The boreal forest and taiga are projected to extend further north;
temperate grasslands and coniferous forests may expand their range, while both the tundra and
the polar deserts will shrink. Along with evidence for the reduction of ice cover in the arctic sea,
there is sufficient agreement that permafrost will keep on thawing leading to subsidence in
coastal areas (Cruz et al. 2007). This, in combination with sea level rise will accelerate coastal
erosion in the Arctic Circle and threaten especially coastal wetlands.

In general terms, warming will produce a shift of both flora and fauna to higher latitudes and
altitudes, although the precise changes in terms of community composition is uncertain, as it is
also dependent on species interactions. Species’ shifts have been already documented around the
Mediterranean, in Scandinavia, in part of the Carpathians and in the Urals (Alcamo et al. 2007).
However, some species and ecosystems, namely those that already occupy the most extreme
areas in the alpine (altitude) or arctic regions (latitude), will have nowhere to go (i.e. no real
adaptation option) and are under a serious threat of disappearing. The breeding habitats of
several migratory birds in the arctic are going to be exposed to drastic changes (or they will
disappear altogether) and the consequences are at the moment unpredictable. It is hypothesized
that climate change will increase the general extinction rates, therefore aggravating the global
biodiversity loss crisis. As species push northward, warmer and wetter conditions are also
expected to create more opportunities for invasive species to expand their range (Reid 2006,
Alcamo et al. 2007) .

Climatic changing averages are also going to modify the phenology3 of several species. This
may generate mismatches between species and interfere with interactions such as predation,
pollination and diseases (Reid 2006).

1.1.3 Extreme events- droughts, floods

Extreme events have also the potential to negatively affect biodiversity. Higher temperatures
have prompted concern about increasing intensity and frequency of forest fires. The Palmer
drought index for the last two decades has shown increasing drought conditions across most of
ECA (see Figure 4 Climate Science Section). The GCM projections allow to project worsening
drought conditions in southern areas across ECA, due to a combination of temperature increase
and a decrease in mean annual rainfall (see Figure 13 & 18 Climate Science section). For the

2 For this variable there is complete concordance between the models
3 In ecology phenology refers to the timing of seasonal phenomena (e.g. the phenology of a species could be from
april to september)
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northern and eastern areas projections of drought are more complicated due to a combination of
warmer and wetter4 conditions, with mean annual rainfall possibly reaching + 10% (see Climate
Science Section).

The sum of current evidence and model predictions indicate that the most vulnerable areas are
going to be the ones that will experience the stronger climatic variations, therefore, the far north
and south areas of ECA and the mountainous regions.

4 This is projected particularly for the north-eastern areas, therefore with exclusion of southern europe, tajikistan,
the caucasus and around the black sea basin (see Figure 13 Climate Science Section).
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2. Adaptation for Biodiversity

2.1 Framing the biodiversity question

Species, communities, habitats and ecosystems will undergo modifications as a result of climatic
changes. Some species will be able to adapt to climate change by shifting their ranges, while
others, particularly those specialized to living in a narrow range of extreme environmental
conditions will be exposed to a much higher extinction risk.

As species and ecosystems change and shift, so do the goods and services they offer. The
intensity and location of valued services may change, or they may disappear altogether, with
consequences for human welfare. These phenomena bring about a reallocation of resources,
with some regions possibly losing out while some gain new opportunities.

An example can be used to further clarify the issue. Some insects, in particular honeybees,
provide an ecosystem service critical both to wildlife and to human sustenance: pollination.

The increase in temperature may modify environmental conditions and force pollinators to
migrate to higher latitudes and altitudes in order to survive5. The capacity of these organisms for
autonomous adaptation (i.e. range shift) is dependent on their biology (e.g. physiology and
motility), but also on the characteristics of the surrounding vegetational landscape. Presence of
the right vegetative matrix, with refugia and corridors allowing the insects to spread, feed and
reproduce, is needed for autonomous adaptation6. On the contrary, a barren wasteland
interposed between the original location and the new preferred site would represent a serious
threat, and may result in the loss of an entire population. Hence, the first aspect of biodiversity
adaptation consists in understanding how to protect the resilience of natural systems, i.e. how to
foster those conditions that allow species and ecosystems to adapt autonomously.

Migration of pollinators may also entail a relocation of some pollination services, and as a result
some agricultural areas may experience a reduction in production; human societies will need to
adapt to those changes that affect their wellbeing through impacts on biodiversity and the
ecosystem services it supports. The issue here is about how we can modify our standard
operations and reduce the vulnerability of sectors like agriculture, forestry, aquaculture, tourism
etc to changes occurring in critical ecosystem services.

If we consider a hypothetic ecosystem, exposure to climate change events can result in the
following categories of negative impacts:
A. Loss of biodiversity (damage from the existence value point of view – biodiversity intrinsic
value)
B. Reduction or failure of ecosystem goods and services in a specific area because of habitat
loss and biodiversity reduction (Biodiversity has failed to adapt)

5 According to recent analysis climate change may anticipate the time of flowering, with a resulting disruption of the
synchronization between pollinators emergence (according to their life cycle) and the flowering of plant.
6 The effects of temperature change can also be very fast and reduce fitness of a pollinator species before any
effective adaptation mechanism has the chance to set in.
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C. Reduction and loss of environmental goods and services due to migration of ecosystems
(shift and replacement).

BOX 2. Values of Biodiversity

The rationale for nature conservation builds on three main values assigned to biodiversity: direct use value
(including option value), indirect use value, and ethical (or existence) value.

Existence value: This refers to the inherent value of all living organisms, and appeals to man’ stewardship role
toward the

Direct use value: Biodiversity offers an infinite array of goods and raw materials for human self-sustenance. In
addition most of the chemicals used either in industry and in medicine are derived from plants and animals. Loss of
biodiversity translates into a reduction of future opportunities for new discoveries that could benefit medical
research or industrial development (loss of the option value).

Indirect use value: indirect use values arise from biodiversity as the basis of environmental services.

This report will focus primarily on the two closely related scenarios A and B. C is implicit in
other sections included in the umbrella report.

Scenario A represents the threat to the intrinsic existence value of biodiversity, while scenario B
centers on the option value of Biodiversity (BOX 2). In the context of both scenarios, the main
adaptation option consists in reducing the vulnerability of the system by tackling those stressors
that undermine the capacity for autonomous adaptation of species and ecosystems. Possible
strategies are:
1. Actions to reduce impacts of other threats and improve resilience (Figure 4)
a. Control habitat loss
b. Reduce habitat fragmentation and increase connectivity
c. Maintain metapopulations
d. Reinforce monitoring
e. Reduce pollution
f. Promote genetic diversity
g. Control the spread of exotic species
2. Expand reserves and change approach to biodiversity conservation (Policy and technical
interventions)
3. Planning based on future scenarios (Policy and technical interventions)
4. Technological options (e.g. conservation in seed banks)

In general, conservationists consider the first three options as preferable, while maintaining that
the fourth one should be limited to especially dramatic situations. The ECA region hosts many
of the wild relatives of key crop species. Because of their critical value, a technological option
(e.g. conservation in seed banks) may turn out to be necessary. Resorting to this solution may
have also some drawbacks; extracting these species from their environment means exempting
them from selection pressure (i.e. no evolution), which may result in their being unfit for future
climatic conditions (i.e. we are increasing the long-term sensitivity and overall vulnerability of
these species to climatic changes). On the other hand it has to be kept in mind that the genetic
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