Conservation and Sustainable Use of the Biosphere - WBGU

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Conservation and Sustainable Use of the Biosphere - WBGU

Development of landscapes under human influence

E 2

E 2.1

Development of the cultivated landscape in

Central Europe

A steady high has developed over Germany. The

weather forecast is predicting warm and sunny days

for the late summer; the viewers are wished a pleasant

weekend.To illustrate this, pictures of the flowering

heather at Wilseder Berg with white flocks of

sheep are shown. On the next day, many people from

the urban areas around Hamburg, Bremen, Hanover

and even the Ruhr region get into their cars in order

to experience the ‘natural spectacle’ of the heather in

flower in Germany’s oldest nature reserve, after a car

journey of one to three hours on the motorway. On

their subsequent walk on sandy paths between flowering

heather and dark green juniper bushes, only

very few are aware that the protected landscape is

not a natural landscape at all. This is what is left of a

cultivated landscape that was still widespread in

north-west Europe 150–200 years ago that came

about because of an economic practice that lasted for

centuries, if not millennia – heath farming. The basis

of this agriculture on the low-nutrient soils of the Ice

Age deposits was to remove the nutrients accumulated

in the humus from large areas in order to

spread them as fertilizer on the small arable fields

close to the farm, after they had been used as bedding

in the barns. This meant that it was possible to practise

subsistence farming on poor soils over a long

period. However, this was to the detriment of the

areas from which the nutrients were removed, which

were around 10–30 times larger than the arable land.

These areas lost nutrients and acidified, with the

result that in the end only the undemanding Calluna

heather and a few juniper bushes would grow there.

The heather provided the primary grazing for the

Heidschnucke breed of sheep and the primary source

of nectar for bees, that together provided the main

products of this type of agriculture: wool, meat,

honey and wax. These forms of landscape created by

humans, which took up wide expanses of Europe, disappeared

after honey was replaced by sugar beet,

wax by petrochemical products and finer imported

wool pushed rough Schnucke wool out of the market.

This example illustrates various aspects. On the

one hand, it can be seen that mankind is capable of

radically changing landscapes – and this is not just a

recent development. On the other hand, it shows that

landscape forms created through use and the living

communities that shape them can only be conserved

when the use that brought them into being is also

maintained. However, it is not only the use that has to

be continued; the climatic conditions have to continue.

Thus, in order to conserve these sites, eutrophication

resulting from nitrogen deposits also has to be

avoided, a process which the visitors who come by car

play a part in. Landscapes and their communities of

organisms are thus dynamic ecosystems that can

quickly adapt to changing environmental conditions.

For millennia humankind has been a shaping factor

in all of this.

E 2.1.1

Background

At the end of the Tertiary period, ie around 2.5 million

years ago, an extraordinarily species-rich, warmtemperate

woody flora had developed over large

areas of Europe. It comprised a wide variety of deciduous

broad-leaved trees and many conifers. Sclerophyllous

evergreens grew in the Mediterranean area

and an Alpine flora established itself in the newlyformed

high mountains. As far as the fauna of the

Tertiary is concerned, the evolution of mammals is

most worth a mention, including the emergence of

human ancestors. Radical changes for the plant and

animal communities came with the Ice Age, the Pleistocene

2.3–2.5 million years ago and the associated

temperature decreases. A lasting process of adaptation

by the biosphere took place over several cyclical

cold and hot periods (glacial and interglacial periods).

During the cold phases there was large-scale

glaciation, especially in Scandinavia and the British

Isles. The young high mountains running from the

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