Bài giảng climate change and biodiversity

adapted from Hughes 2000, TREEPotential pathways of biodiversity impacts from climate change Effects on physiology Effects on phenology Effects on distributions Evolutionary adaptation

Impacts of Climate

Change on Biodiversity

We are altering the system

Variations of the Earth‟s surface temperature

over the past 1,000 years

(IPCC, 2001)

3 2

4

A2 A1B

(adapted from Hughes 2000, TREE)

Potential pathways of biodiversity impacts from climate change

Effects on physiology

Effects on phenology

Effects on

distributions Evolutionary adaptation

Changes to species interactions

Effects on abundance

Further effects on distributions and abundance

Extinction of some species

Changes in ecological communities

(Foden et al., 2008)

(Sala et al 2000, Science)

Relative effect of major drivers of changes on biodiversity

Is a climate change signal already apparent?

Phenological changes:

E.g UK birds are

laying eggs earlier

(Crick et al 1997, Nature)

a, corn bunting; b, chiffchaff; c, magpie

Bird phenology and asynchrony with

food supply:

Geese not able to acquire adequate body stores quickly enough to breed before the

quality of food for their young decreased.

Van Der Jeugd et al 2009

Bird phenology and asynchrony with

Populations of pied flycatchers in some areas in

Europe declined up to 90% because chicks did not have enough food

Visser et al (2006)

Winter moth caterpillar

Pied flycatcher

Is a climate change signal already apparent?

Is a climate change signal already apparent?

Pole-ward distribution shifts: (P

Observed Ecological Impacts Range shifts

Mammals

Red fox

has expanded into the North

Arctic fox has contracted to Atlantic

Unable to move

Quiver tree in Namibia

Quiver trees are

distributed in South

Africa This species

can retain water in

its leaves and stems,

and lives more than

200 years Over the

last decades, more

Is a climate change signal already apparent?

Upslope distribution shifts: an example from Madagascar…

NASA MODIS

Rocky outcrops and heathland at 2750m

(Raxworthy et al 2008 Global Change Biology)

Elevationaldisplacement of

(Raxworthy et al 2008 Global Change Biology)

Mean displacement = 65m upslope

(p<0.01)

The extinct golden toad (Bufo periglenes)

Is a climate change signal already apparent?

Extinction:

E.g widespread amphibian extinction

in Central and South America

(~30 species of harlequin frogs feared

extinct)

1 Lifting-cloud-base hypothesis

(Pounds et al Nature 1999)

2 Climate-linked-epidemic hypothesis

(Pounds et al Nature 2006)

3 Climate-driven reductions in the

quantity of standing leaf-litter

(Whitfield et al PNAS 2007)

C.H Smith, US Fish and Wildlife Service

Pest species and disease are also moving

polewards and upward

Eg Chytrid fungus

Cooler days and warmer nights have resulted in favorable conditions at mid-elevation sites

Changes in dynamics of the skin fungus is

implicated in subsequent extinctions of 74

harlequin frog species

Is a climate change signal already apparent?

“This suite of analyses generates „very high confidence‟ (as laid down by the IPCC) that climate change is

already affecting living systems”

(Parmesan and Yohe 2003, Nature)

“the balance of evidence from these studies strongly suggests that a significant impact of global warming is already discernible in animal and plant populations”

(Root et al 2003, Nature)

present day

(Pearson & Dawson 2003 Global Ecology and Biogeography)

What might the future hold?

Predicting distribution shifts using niche-based species distribution

models

Modeling algorithm (e.g

Maxent, GARP)

future

„Bioclimate envelope‟ predictions for Twinflower (left) and White-beaked sedge (right)

Present day 2050s projection Present day 2050s projection

Predicted distribution shifts under climate change

(Pearson et al 2002 Ecological Modelling)

Extinction risk from climate change

(Thomas et al 2004, Nature)

“we predict, on the basis of range climate-warming scenarios for

mid-2050, that 15-37% of species in our sample of regions and taxa will be

„committed to extinction‟”

S = cA z

future Thomas et al (2004, Nature):

species-level extinction estimated to be 21-32% with universal dispersal, and 38-52%

with no dispersal (under maximum projected climate change)

Dispersal ability – will species be able to „keep up‟

with changing climate?

But… what can we predict with confidence?

• We have a fair idea of general patterns

and trends that can be expected over the next century, including:

– upslope and poleward distribution shifts

– changes in phenology and abundance

– extinction

• However, the magnitude of future impacts

of climate change on biodiversity remains difficult to predict.

Vulnerable species

• Specialized habitat and/or microhabitat requirements

• Narrow environmental tolerances or thresholds that are

likely to be exceeded due to climate change at any stage

of life cycle

• Dependence on specific environmental triggers or cues that are likely to be disrupted by climate change

• Dependence on interspecific interactions which are likely

to be disrupted by climate change

• Poor ability or limited opportunity to disperse to or colonize

a new or more suitable range

Climate Change in

Vietnam

Source: MONRE, 2009

Rising temperature in Vietnam

-Over the last 50 years,

the annual average

- Northern climate zones

increase faster than

those of southern ones

Climate change scenarios in Vietnam

Climate change scenarios in Vietnam

Source: MONRE, 2009

- About half (1.4 million

hectares) of the Mekong

Delta‟s agriculture lands

might be inundated by the

end of the century.

- A quarter of Ho Chi Minh

City, home to more than six

millions, would be under

water.

Frequency of extreme weather events

- Rate and severity of

EWE have increased

over the last decades,

and might go beyond

ecosystem resilience in

many areas in the

country in the future

- Urban communities are susceptible to impacts of climate change, especially due

to conversion of wetland, which results in loss of key ecosystem services, e.g., water retention

Impacts of CC on human health

Source: Patz et al., 2000

Impacts of CC on the economy

Source: WWF, 2009

- Climate change is expected to cause significant impacts on the Greater Mekong Region‟s

agriculture productivity.

- In Vietnam, Mekong Delta produces about half of Vietnam‟s rice volume, 60% of fish and shrimp production, and 80% of fruit crops.

Impacts of CC on the economy

- Inland fisheries are expected to

be vulnerable to changes in hydrology and water chemistry induced by impacts of climate change.

- Rising sea level, more severe storms, and salt water intrusion in the deltas will likely adversely affect the aquaculture industry.

Challenges in Vietnam

• Vietnam is one of the countries most vulnerable to

impacts of climate change (Dasgupta et al., 2009)

• Human migration from lowland to upland areas as a result of climate change can have immense impacts on biodiversity

• Impacts of climate change in combination with

existing conservation problems will likely exert profound changes to biodiversity and ecosystem services

Sea level rise and protected areas

Source: ICEM, 2008

Challenges in Vietnam

• Habitat fragmentation makes it difficult to design biological corridors for

species dispersal in the context of climate change.

• Complicated landuse changes associated with human movement

provide limited options for conservation planning, e.g., redesigning protected

area network to accommodate species movements.

Source: ICEM, 2008

• Climate change has had a discernable affect on plant and animal populations in recent decades

• Human-induced climate change is expected to

be more rapid and of greater magnitude than has been experienced over the last 10,000 years

Combined with other factors, including habitat

destruction, climate change can be expected to have an important impact on biodiversity and

ecosystem functioning over the coming century

• Climate change therefore raises important

challenges for conservation