Desertification Atlas (Global) Maps 1-20

INTRODUCTION
Desertification/Land Degradation - The Background

More than 6.1 billion hectares, over one third of the Earth's land
area, is dryland. Nearly one billion hectares of this area are
naturally hvperarid deserts, with very low biological
productivity. The remaining 5.1 billion hectares are made up of arid,
semiarid and dry subhumid areas, part of which have become desert
since the dawn of civilization while other parts of these areas are
still being degraded by human action today. These lands are the
habitat and the source of livelihood for one quarter of the world's
population. They are areas characterized by the persistent natural
menace of recurrent drought, a natural hazard accentuated by
imbalanced management of natural resources. Particularly acute
drought years in the Sahelian region of Africa from 1968 to 1973, and
their tragic effects on the peoples of the region, drew worldwide
attention to the problems of human survival and development in
drylands, particularly on desert margins. These problems have been
addressed by the United Nations (UN) General Assembly, in conformity
with the Charter of the United Nations. The UN General Assembly's
Resolution 3202 (vi) of 1 May 1974 recommended that the international
community undertake concrete and speedy measures to arrest
desertification and assist the economic development of affected
areas. The Economic and Social Council's Resolution 1878 (LVII) of 16
July 1974 requested all the concerned organizations of the UN system
to pursue a broad attack on the drought problem. Decisions of the
Governing Councils of the UN Development Programme (UNDP) and the UN
Environment Programme (UNEP) emphasized the need for undertaking
measures to check the spread of desert conditions. The General
Assembly then decided, by Resolution 3337 (xxix) of 17 December 1974,
to initiate concerted international action to combat desertification
and, in order to provide an impetus to this action, to convene a UN
Conference on Desertification (UNCOD), between 29 August and 9
September 1977 in Nairobi, Kenya, which would produce an effective,
comprehensive and coordinated programme for solving the problem. For
the purposes of this atlas, desertification/land degradation is
defined as: Land degradation in arid, semiarid and dry subhumid areas
resulting mainly from adverse human impact.