ecosystem multi-functionality and biodiversity in production forests. Allowing trees
and forests to mature by significantly minimizing silvicultural interventions would
benefit many species that depend on habitats associated with late development
phases and a long forest continuity.
Forest ecosystems play a crucial role in global biogeochemical cycles and store
huge amounts of carbon. Future carbon sequestration and storage, however, critically depend on tree longevity. Thus, forest preservation and restoration rather than
afforestation seems to be a promising way for climate change mitigation. Importantly, species-rich, semi-natural and cultural ecosystems should not be sacrificed for
tree plantations, to safeguard their rare, endemic and threatened species. Overall,
sustaining the functional integrity of forest ecosystems would favour synergies
among biodiversity and multiple benefits that forests provide for human well-being.
5.2.7 Deserts and Rocky Ecosystems
Sparsely vegetated areas such as deserts, semi-deserts, rocks or screes are inhabited
by many rare, endemic and also endangered species, especially if the landscape
heterogeneity in space is high. The importance of these habitats for the existence of
organisms is often underestimated.
Furthermore, the increasing range of desert in many cases is the consequence of
agriculture, e.g. due to overgrazing in marginal rangelands that are sensitive to
desertification, and has less to do with climate change. This has unfortunately been
a theme over the past two centuries in dry zones of Asia, the African Sahel, Karoo of
southern Africa, Australian Outback and south-western North America, following
the onset of major livestock farming with management practices unsuited to the
environmental context. Restoration is sometimes possible, at a huge cost, but is often
impossible.
Desert animals are severely persecuted in some places, with local cultural activities decimating original wildlife; North Africa and the Middle East are examples of
areas with some of the World’s most endangered antelope species, as well as having
several extinct desert species from human persecution. In contrast, some desert
animals have benefited from domestication and relocation to other continents—the
camel and sakar falcon are some examples. War in many dry and desert areas is also
a profound impact on biodiversity: war-induced poverty and migration, as well as
hunting by militia, has decimated wildlife in the African Sahel, southern Angola, the
Horn of Africa, and parts of central Asia. Desert plants can be highly sought after in
the horticultural trade—for example the succulent wealth of Namaqualand in
South Africa is under tremendous pressure from illegal plant collectors for the
international market. In some areas, mineral wealth in arid regions competes with
conservation needs, such as in the Northern Cape, South Africa, where various
mineral riches require open cast mining that impacts rich local arid endemism. In
contrast, politically stable, arid countries like Botswana, Namibia and
South Africa—which share the Kalahari and Namib Deserts between them—have
successfully protected their “big five” wildlife and other biodiversity through
Land Use Change and the Future of Biodiversity
477
and forests to mature by significantly minimizing silvicultural interventions would
benefit many species that depend on habitats associated with late development
phases and a long forest continuity.
Forest ecosystems play a crucial role in global biogeochemical cycles and store
huge amounts of carbon. Future carbon sequestration and storage, however, critically depend on tree longevity. Thus, forest preservation and restoration rather than
afforestation seems to be a promising way for climate change mitigation. Importantly, species-rich, semi-natural and cultural ecosystems should not be sacrificed for
tree plantations, to safeguard their rare, endemic and threatened species. Overall,
sustaining the functional integrity of forest ecosystems would favour synergies
among biodiversity and multiple benefits that forests provide for human well-being.
5.2.7 Deserts and Rocky Ecosystems
Sparsely vegetated areas such as deserts, semi-deserts, rocks or screes are inhabited
by many rare, endemic and also endangered species, especially if the landscape
heterogeneity in space is high. The importance of these habitats for the existence of
organisms is often underestimated.
Furthermore, the increasing range of desert in many cases is the consequence of
agriculture, e.g. due to overgrazing in marginal rangelands that are sensitive to
desertification, and has less to do with climate change. This has unfortunately been
a theme over the past two centuries in dry zones of Asia, the African Sahel, Karoo of
southern Africa, Australian Outback and south-western North America, following
the onset of major livestock farming with management practices unsuited to the
environmental context. Restoration is sometimes possible, at a huge cost, but is often
impossible.
Desert animals are severely persecuted in some places, with local cultural activities decimating original wildlife; North Africa and the Middle East are examples of
areas with some of the World’s most endangered antelope species, as well as having
several extinct desert species from human persecution. In contrast, some desert
animals have benefited from domestication and relocation to other continents—the
camel and sakar falcon are some examples. War in many dry and desert areas is also
a profound impact on biodiversity: war-induced poverty and migration, as well as
hunting by militia, has decimated wildlife in the African Sahel, southern Angola, the
Horn of Africa, and parts of central Asia. Desert plants can be highly sought after in
the horticultural trade—for example the succulent wealth of Namaqualand in
South Africa is under tremendous pressure from illegal plant collectors for the
international market. In some areas, mineral wealth in arid regions competes with
conservation needs, such as in the Northern Cape, South Africa, where various
mineral riches require open cast mining that impacts rich local arid endemism. In
contrast, politically stable, arid countries like Botswana, Namibia and
South Africa—which share the Kalahari and Namib Deserts between them—have
successfully protected their “big five” wildlife and other biodiversity through
Land Use Change and the Future of Biodiversity
477