Download Biodiversity and ecosystem services in historical - ALTER-Net

Biodiversity and Ecosystem
Services in historical perspective
Univ.-Prof. Ing. Dr. Verena Winiwarter
Centre for Environmental History, Vienna
http://umweltgeschichte.uniklu.ac.at/home.php
ALTER-Net conference - Biodiversity and Ecosystem services; what
is the link between the two? Vienna, November 3-4, 2010
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A quick definition and appraisal of
ecosystem services
„Ecosystem services are defined as ‘‘the
benefits people obtain from ecosystems’’
(Millennium Ecosystem Assessment,
2005). I think this is a good, appropriately
broad and appropriately vague definition.“
(Costanza 2008, 350)
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Biodiversity and Ecosystem
Services are connected
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The loss of services to humanity following extinctions
ranges from trivial to catastrophic, depending on the
number of elements (populations, species, guilds)
deleted and the degree of control each exerted in the
system. Most attempts to substitute other organisms
for those lost have been unsuccessful, to one degree
or another, and prospects for increasing the success
rate in the foreseeable future are not great. Attempts to
supply the lost services by other means tend to be
expensive failures in the long run. A conservative
approach to the maintenance of services through
minimizing anthropogenic extinctions is
recommended.
Paul R. Ehrlich and Harold A. Mooney, Extinction, Substitution, and
Ecosystem Services BioScience, Vol. 33, No. 4 (Apr. 1983), pp. 248254, here 248
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The argument
• For subsistence hunter-gatherers, biodiversity, ecosystem
services and their livelihood were one, as they tapped energy
flows in natural ecosystems.
• Pre-industrial agriculturalists relied on ecosystem services for
their livelihood. They diverted energy from natural flows into
their agro-ecosystems. Some natural systems became
“pests”, competing non-agricultural land-uses could endanger
the services agriculture relied on.
• Industrial food-producing systems take a major portion of their
energy from fossil fuels, and thus can seriously compromise
natural energy flows. Agricultural AND non-agricultural landuses endanger ecosystem services.
• In a post-fossil fuel world, this will change. Starting with
degraded ecosystems will make this change difficult or
impossible.
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The example:
Silver Mining in Colonial Mexico
Mining facts:
From the 16th to 19th centuries, over 50.000 tons of silver
were sent from the colony to Spain.
For each kilogram more than 6000 m2 forest were needed,
altogether more than 315.000 km2.
Between 1558 and 1804, 20% of Mexico, an area the size of
Italy or Poland, was deforested.
While some indigenous peoples worked for the mines, initially
many fought against the Spaniards.
Daviken Studnicki-Gizbert, David Schecter, Environmental History,
2010, 94-119.
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Ecosystem Facts
Hilly to mountainous area, low
water input, high solar radiation,
high daytime temperatures.
Keystone species: Shrub oak,
oaks, willows, poplars,
mesquite.
Ecosystem services by mesquite and other trees
Leguminous species, very long roots able to tap low groundwater,
act as nitrogen pump (300 kg NH4NO3/ y/ha), nitrogen is spread
into surroundings during torrential rains, pods and seeds are
source of protein ands carbohydrates for animals, SHADE reduces
temperature and evaporation, 15 mammal and 95 bird species
counted in one mesquite stand
All trees: critical in soil building, erosion protection by dissipation of
rain energy through leaf cover, divert water into subsoil.
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More ecosystem facts
• Vegetated areas in semi-arid
environments hold water for 150-225 days
longer than bare soil patches.
• Fertile soil, water, shade and wind cover
lmade mixed Mesquite forests habitats of
high biodiversity.
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Guachichile-Chichimecan uses of
the Mesquite Forests
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Human uses of Mesquite:
pods as a staple food (flour)
sewing needles from the thorns;
inner bark for baskets and fabric;
sap for black dye;
honey from the nectar
wood for bows and arrows for hunting,
firewood: smokeless, burns slowly
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3 people could
produce 40 kg of
flour per day!
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Mesquite forests were rich foraging
grounds
• Deer, rats, birds were hunted, insects
gathered
• Other plant species were also used:
• Acorns,
• Agave juice,
• Prickly pear cactus fruit
Ecosystem services in a diverse ecosystem
provided THE LIVELIHOOD of huntergatherers.
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Zimapán, México, ca. 1898
Denuding the mountains robbed the indigenous
peoples of their means of survival.
Working for Spanish mines or accepting the offer to
settle, convert to Christian religion and become
agriculturalists were their only resort.
Silver (in the money used for 'Paz por compra‘)
© became
Lily Diaz
a substitute for the ecosystem services no
longer available.
Pueblo Fantasma (Ghost Town) at the old silver mine above
Real de Catorce in San Luis Potosi, Mexico. Oct. 28, 2008
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Davis O'Keeffe
How about diversity today?
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Vaclav Smil,
Enriching the
Earth, 2004, 142
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The Haber process is energy-intensive and is estimated to
consume approximately 1% of the energy used worldwide
each year.
The link between energy and fertilizer production is very
important because the Haber process is used to produce
about 500 million tons of nitrogen fertilizer each year
which in turn supports about 40% of the world's
population.
Any decrease in the availability of energy, particularly
from a decline in fossil fuel production (used as energy
itself and as a feedstock) could cause a significant
interruption in the production of fertilizer.
(The Encyclopedia of Earth, 2010)
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• For subsistence hunter-gatherers, biodiversity, ecosystem
services and their livelihood were one, as they tapped energy
Solar
energy
was
harvested.
flows in natural ecosystems.
• Pre-industrial agriculturalists relied on ecosystem services for
their livelihood. They diverted energy from natural flows into their
Agriculture
had a positive energy balance, solar
agro-ecosystems. Some natural systems became “pests”,
energy
harvested.
competingwas
non-agricultural
land-uses could endanger the
services agriculture relied on.
• Industrial food-producing systems take a major portion of their
energy from fossil
and thus
can seriously
compromise
Agriculture
hasfuels,
at best
a slightly
positive
energy
natural energy
flows.
Agricultural
ANDor
non-agricultural
balance,
more
often
it is zero
negative. land-uses
endanger ecosystem services.
• In a post-fossil fuel world, energy . Starting with degraded
ecosystems will make this change difficult or impossible.
We will need to harvest solar energy again.
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Nature and Us
The labour of nature is paid, not because she does
much, but because she does little. In proportion
as she becomes niggardly in her gifts, she
exacts a greater price for her work. Where she
is unificently beneficent, she always works gratis.
(David Ricardo 1817)
• If we start a post-fossil future with simplified
ecosystems, the price of nature will be great.
• In the post-fossil world, the connection
between livelihoods, biodiversity and
ecosystem services will tighten for ALL.
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