Conservation and Sustainable Use of the Biosphere - WBGU

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Conservation and Sustainable Use of the Biosphere - WBGU

Life in the Earth System: BIOSPHERE I F 1.1

213

F 1.4

Towards global control: BIOSPHERE III

With hindsight, the essential failure of the BIOSPHERE

II experiment was anything but a surprise. The physiological

and metabolic complexity of BIOSPHERE I,

which was given a broad-brush outline in the last section,

is after all the result of thousand millions of

years of evolution in the interaction of opportunism

and functionality. Spurred on by variously intense

external and internal disruptions somewhere

between the two extremes of chance and purpose, a

system has organized itself that, perhaps, is only possible

just once in the entire universe.

Despite the failures, NASA is pushing forward

under its CELSS programme (Controlled Ecological

Life Support Systems) to develop artificial agricultural

ecosystems that are intended to secure maximum

food production in extra-terrestrial conditions

(Volk, 1996). And ‘geo-engineering’, the science that

is seeking to ‘repair’ the unintentional ecological

faux pas of the industrial society (such as the

thoughtless release of CFCs and CO 2

) on a grand

scale, can already look back on initial successes. For

example, fertilizing the tropical ocean west of the

Galápagos Islands with just 500kg of iron sulphate

triggered a large bloom of algae (Coale et al, 1996).

This demonstrated that the marine ‘biological pump’

can be strengthened in a targeted fashion to precipitate

carbohydrate from the water column (at least for

a short period).

The quality of such experiments to control habitats

is still very low, but is there really an alternative

to progressing on the road to BIOSPHERE III, a controlled

global environment? Humankind is already

rebuilding the planetary ecosystem with rapidly

growing depth and scale of intervention, so far it has

to be said without any kind of comprehensive blueprint!

For example, in BIOSPHERE I approx 40 per

cent of the area able to sustain vegetation is covered

with forest (Burschel, 1995; WRI, 1997); this proportion

has shrunk in the landscapes shaped by

humankind to a current average of some 27 per cent

(FAO, 1997b).And the great CO 2

atmosphere enrichment

experiment ‘staged’ by the burning of fossil

fuels will ultimately impact the biosphere less indirectly

through the ‘side effect’ of climate change, but

more directly through the overfertilization shock.

Compelling evidence for the CO 2

fertilization

effect is the observation that the annual respiration

of planetary life is becoming deeper (Box F 1.1-1).

The impact on the composition of terrestrial ecosystems

as a result of changed competitive conditions

cannot be predicted clearly, but will no doubt be considerable.

The older C 3

plants (which include wheat

and rice), older in terms of evolutionary history, have

adapted in an optimum fashion to the carbon-dioxide-rich

atmosphere and could deny the ‘younger’ C 4

plants (such as maize, sorghum and sugar cane, but

also many natural grasses) of their place in the rankings

in terms of nutrient use. This tendency is however

countered by the fact that a warmer ambient

temperature tends metabolically to favour the C 4

plant (Taiz and Zeiger, 1991; Monson and Moore,

1989).

There is much that would speak in favour of transferring

this largely erratic process into a well controlled

process in the sense of biosphere governance,

just as at the latest with the advent of the Kyoto Protocol,

management of the Earth’s atmosphere

became a project of the modern age. But what would

that type of governance be like? A grand typology of

possible strategies can be sketched out in advance.

There are three main roles from which humankind

must chose: the role of the preserver (‘Noah’), the

nurturer or steward (‘curator’) and the shaper/architect

(‘demiurge’). The modern Noah would not just

try to save all species in creation, but also every type

of landscape and ecosystem, too.The biosphere curator,

mindful of his responsibility, would carefully and

after great thought select or transform individual elements

from the existing biotic world. The demiurge

of the Third Millennium would by contrast try as an

architect to ‘improve’ the biosphere and its conditions

of subsistence – ameliorative aspirations ranging

from key agrarian plants to a global land use concept.

Proponents of the demiurge principle are ultimately

motivated by the insight that today’s biosphere

is only operating at around 30 per cent of its

true potential as a photosynthetic energy reservoir

(Volk, 1998). As indicated above, this could change

very quickly, if the industrial society understood how

to make intelligent use of the combination of humaninduced

environmental trends, CO 2

enrichment in

the atmosphere, nitrogen enrichment in ecosystems

and global warming. The American agroscientist S B

Idso waxes lyrical at such thoughts: ‘... for we appear

to be experiencing the initial stages of what could

truly be called a rebirth of the biosphere, the beginning

of a biological rejuvenation that is without

precedent in all of human history, but which is not

atypical of great periods of our geological past, where

the CO 2

content of the atmosphere was several times

greater than it is today. Biologically speaking, those

bygone eras of high CO 2

were truly “the good old

days” [...] Fortunately for us, and for all of the other

life forms with which we share the planet, the mounting

array of evidence [...] suggests that humanity may

well be in a course that will carry us back to such

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