Conservation and Sustainable Use of the Biosphere - WBGU

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Conservation and Sustainable Use of the Biosphere - WBGU

Third biological imperative: maintain biopotential for the future I 1.3

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tural methods lead to intolerably high erosion rates.

For such zones ‘guidelines’ may be developed that

can be expressed in practice not in the renunciation

of use of certain areas, but in rules for reasonable use

with the intention of guaranteeing that the given use

stays within the realm of sustainability (Box I 1.1-1;

Section E 3.9).

I 1.2

Second biological imperative: safeguard existing

biological resources

From the demand that the production of food and

renewable resources (‘food and fibre’) may not be

endangered (Section D 3.1), the following biological

imperative may be derived on the basis of the concept

of ‘use value’: Biological resources that are

required for the (constantly necessary) adaptation

and further development of crop plants and livestock

animals may not be endangered.

This includes the acutely endangered enormous

diversity of traditional, locally adapted varieties that

are of considerable importance for plant breeding

and food security. The Council is concerned because

this valuable diversity of traditional varieties is

increasingly disappearing (genetic erosion). Particular

efforts are required here and these are elucidated

in more detail in Sections D 3.1 and I 3. Ex-situ

conservation (eg in gene banks) may not be the solution

in all cases but, given the worldwide situation, it

should increasingly be pursued (Section D 3.1; FAO,

1996c).

Furthermore, the wild, related species of the cultivars

we use should be protected. The plant-based

genetic resources in what are termed ‘gene centres’

should be given particular consideration (Hammer,

1998; Section D 3.1).These centres are zones in which

valuable genetic resources occur in a particularly

concentrated form. They cannot be protected as a

whole because of their extensive geographic spread,

and because they do not just house biotopes that contain

valuable genetic resources for wild, related cultivated

plants, but are also themselves a patchwork of

diverse landscape types. Fore these diversity centres

there is a particular responsibility to protect these

resources that should be taken into consideration in

the context of bioregional management (maintaining

genetic resources in situ or on farm; Section D 3.1).

The services that are provided in such bioregions and

which ultimately benefit everyone will in the long

term be extremely difficult to provide unless mechanisms

for supra-regional and global financial compensation

are established, since generally – seen from

the perspective of the local population – this is the

economically less interesting alternative in comparison

with more intensive forms of land use (Section

I 3.5).

Genetic transfer through the release of transgenic

plants can be an endangering factor, eg if the alien

genes have a competitive advantage outside the

agro-ecosystem (Regal, 1994; Section D 3.2). Resistance

to disease, tolerance of cold, drought or salt are

examples of features that could cause a shift in the

competition balance among wild populations if

cross-breeding were to occur. And so the use of this

technique must be investigated strictly in each individual

case.The release of transgenic plants into gene

centres in which the wild varieties of these cultivars

occur is therefore associated with particular risks. It

cannot be ruled out that the wild populations would

be endangered by hybridization and competitive

pressure and that genetic diversity would be lost as a

result (WBGU, 2000a). For example, genetically

modified maize should not be planted in the original

area of distribution (Mexico) since out-breeding and

possible changes in the competitive balance could

endanger the genetic diversity of the wild species.

I 1.3

Third biological imperative: maintain biopotential

for the future

The biosphere contains many as yet unknown substances

and principles for humankind and this

‘option value’ must be safeguarded for future use.As

was discussed in detail in Section D 3.3 not all sites

are equally interesting in terms of harvesting natural

substances. Particularly high chances of finding rich

pickings in a small area with little investment is naturally

to be found in those areas with high biological

diversity of natural ecosystems (eg tropical forests,

coral reefs). As a result of the variety of ecological

niches and species adaptation to a highly complex

habitat there are in such places a comparatively large

number of interesting ‘solutions’ of a biochemical or

structural nature. These hotspots of biological diversity

are therefore particularly important.

If in areas of high biological diversity there is an

indigenous population, then the traditional knowledge

accumulated over many generations relating to

the different species and their effects can be used to

gain valuable insights for bioprospecting (eg

methods of ethnobotany, Section D 3.3.6, and property

rights, Section I 3.3.3)

Sites at which extreme environmental conditions

have driven species in the course of their evolution to

adapt in very differentiated ways are also interesting.

Examples are sites with extreme abiotic conditions,

eg hot springs, arid areas or deep sea with the particular

pressures of that environment. In areas with a

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