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Transcript of Nature and ecosystem services: a global perspective Andrew Balmford Department of Zoology,...
Nature and
ecosystem
services: a global
perspective Andrew BalmfordDepartment of Zoology, University of Cambridge
What’s happening to nature?
Why does it matter?
Grounds for hope?
What lessons can we learn?
What are nature’s prospects?
Habitat loss~50% of land already converted to farming, forestry, towns…
What’s happening to
nature?
Overkill59% decline in large mammals inside African reserves since 1970
Introduced specieschytrid fungus has already caused dozens of frog extinctions→ 1 in 5 spp. already threatened with extinction
Habitat lossNo slowing
What’s happening to
nature?
Population declineNo slowing
8/10 indicators of state of nature declined5/5 indicators of pressure on nature increased
→ since 2000:
wild-harvested goods (fish,
timber, medicines…)
Why does it matter?
moral, religious and aesthetic
arguments
less visible services (climate
regulation, storm protection,
crop pollination, disease
control…)
Converting what’s left
of nature often
benefits private
individuals, but at
growing cost to
society as a whole –
nowadays often total
costs > benefits
Why does it matter?Economics of ecosystem services
Estimated net costs of each year’s loss of
nature:
~$3 trillion (Balmford et al. 2002)
$2-4.5 trillion (TEEB 2010)
$6.6 trillion (Trucost 2010)
Marginal benefit or
cost of conversion
($/km2/y)
Proportion converted
Loss of waste disposal service provided by South Asia’s vultures after tens of millions poisoned by diclofenac
Why does it matter?
Economics of ecosystem
services
Loss of storm protection provided by US wetlands following drainage
1992 Grand Banks cod collapse cost 40 000 jobs and $3B to Canadian taxpayer
restore optimism
Grounds for hope?
Better understanding
successes could….
identify contributing
factors and so increase
future success rate
Kaziranga NP, Assam
“fortress-and-fines”
conservation
coupled with
exceptional
tolerance of wildlife
have increased
Indian rhino
numbers from
~20→>2000 in 100y
Grounds for hope?
Loma Alta, western
Ecuador
Measuring value of
high-altitude forest
not for biodiversity
but for dry season
fog capture
prompted
community to
declare 40% of their
land as a reserve
Esm
ere
ldas
woodst
ar
Grounds for hope?
Dutch National
Ecological Network
is (almost) on target
to give 17.5% of
land back to nature
by 2018
Grounds for hope?
approaches, motives and
participants are diversifying -
one size doesn’t fit all
What lessons can we learn?
despite diversity, recurrent
themes:
• being bold
• being good, not perfect
• passionate and imaginative
leaders
• broadening the case
conservation interventions do
succeed
threats are growing and
multiplying
~1 generation left for major
changes
but
• same changes required to tackle
climate change and poverty
• ~ half of nature left
• we have the wit and the will to
buy quite a lot of time
What are nature’s prospects?
Working for Water,
South Africa
~$100M/y project
employing >25
000 previously
unskilled people to
clear alien plants
Grounds for hope?
Huntly bauxite mine, Western Australia
global range of jarrah forest
± covered by world’s largest
bauxite concession); mining
involves clear-felling with
minimal restoration
requirements
concerned about future public opinion, Alcoa invested massively in restoration R+D – so restored plots now as rich as before
Grounds for hope?
America Albacore Fisheries
Association
a small fishery catching Pacific albacore with rods (poles) and short lines (trolls)
biologically sustainable and with zero bycatch
overharvesting elsewhere drove prices (in real terms) down from $3100 / tonne (1981) to $1275 / tonne (2006)
pho
to:
Ric
hard
Her
rman
n
www.americanalbacore.com
Grounds for hope?
Marine Stewardship Council
by becoming MSC-certified AAFA gained access to European markets
4000km
AAFA
98 fisheries and >6000 products now certified worldwide – represents >7% of fish caught for human consumption; almost 200 more fisheries under assessment / pre-assessment
problems – Standard criticised as too demanding/easy, limited baseline data, and process costly so limited uptake in developing countries
Some success stories
www.msc.org
Loss of waste disposal
service provided by
South Asia’s vultures
after >10M poisoned by
diclofenac
Why does it matter?
Economics of ecosystem
services
Loss of storm protection
provided by US wetlands
following drainage
such changes will take time
but same changes are required
to tackle climate change and
developing world poverty
~half of nature still remains
success stories suggest that in
some places we have the wit
and the will to buy quite a lot of
time
The glass half-full?
Habitat
conversion
The emptying glass…
40Historic area converted (%)0 20 60 80 100
Mediterranean forest and woodland
Temperate grassland and shrubland
Temperate broadleaf and mixed forest
Tropical/subtropical dry forest
Flooded grassland and savanna
Tropical/subtropical grassland and shrubland
Tropical/subtropical coniferous forest
Deserts and zeric shrubland
Montane grassland and shrubland
Tropical/subtropical moist forest
Temperate conifer forest
Boreal forest/taiga
Tundra
Pre 1950
1950-1990
Predicted 2050
Millennium Ecosystem Assessment 2005
before
after
Overharvesting
reduced great whale
populations by > two-thirds
eaten >99% of Caribbean’s
green turtles
killed every passenger pigeon
The emptying glass…
since industrial revolution reduced
wild habitats and populations by
~50%
removing rest at ~0.5-1.5% /y
79% of fish stocks now fully
exploited, overexploited or
depleted
59% decline in large mammals
inside African protected areas
since 1970
extinction rates ~1000 x
background
1 in 5 spp. threatened already
The emptying glass…
Underlying drivers
population growth
rising per capita consumption
externalities and discounting
growing disconnect from
nature
The emptying glass…
population 1950-2030, UNPD 2006
world totalworld ruralworld urban
Dorset heathland
Thomas Hardy
The importance of
optimism
1978
1960
1811
1934
1960
1978
1996
Norman Moore
Moore 1960 J appl
Ecol 50: 369-391
Loma Alta, western Ecuador
Dusti Becker recognised
importance of forests for
intercepting dry-season (garúa)
fog
dry-season moisture capture in
forest 3-6 times higher than in
plantations or pasture
under conservative
assumptions clearance already
cost village 38M l/dry season
(worth $130 000/y)
Some success stories
Becker 1999 Ambio 28: 156-161
Habitat lossNo slowing
What’s happening to
nature?
Population declineNo slowing
8/10 indicators of state of nature declined5/5 indicators of pressure on nature increased
→ since 2000: