Fjölrit RALA - 05.12.1999, Blaðsíða 101

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UUXlNMIN ETAL.
as little as 200 mm of annual precipitation. This floundering land use structure re-
sulted in a long lasting mismanagement of this big zone.
At the beginning of cultivation, farming activities can usually provide livelihood to
more people than can animal husbandry activities in the sandy land. The local people
thought that farming was a revolutionary action. It was then followed by desertifica-
tion and land abandonment. Some 4 or 5 years later, when the vegetation had recov-
ered to some extent, the local people would repeat their action and create an even
worse degradation of the land. This situation was often accelerated by climatic fluc-
tuations. Finally, this big zone became an ecological fragile one with a farming-
grazing mixed structure and lower capacity for producing food, fodder and fuelwood.
This historical impact on this fragile ecosystem will last for a long period of time.
Regarding the present reasons for desertification in this zone, it should first be con-
sidered that under the harsh natural conditions such as ffequent drought, strong wind,
vast area of sandy ground and short frost-free period, the limited renewable resource
supporting capacity in this fragile eco-system can not bear today’s intensified land use
and the increased population pressure. This kind of a passive situation and the eco-
logical disturbance is thought to be the result of the long lasting floundered pattem of
land management in the whole zone.
Rapid population growth is an important driving force to increase the pressure on the
land resource, because a larger population must induce more activities for needs of life.
In the last 50 years, the population in this zone has doubled. The available cropland per
capita and rangeland per sheep unit has decreased by a factor of three. A series of un-
wise activities, such as overgrazing, over expansion of cropland, abuse of water re-
source, removal of shrubs and trees for fuelwood gathering, etc., has caused wide
spreading of desertification. Urbanization, traffic infrastructure constmction, mine ex-
ploitation, as well as recreation, have also disturbed the land and the vegetation.
In summary, the core of the fragility of the eco-system in this belt is thought to be
the imbalance between the anthropogenic pressure and the limited renewable resource
supporting capacity. In addition, some inappropriate strategies of desertification con-
trol have delayed the process of desertification reversion and even stimulated the de-
velopment of desertification in this zone. In the recent 50 years, with the political im-
pact of the Great Leap Forwards (1957-1960) and the Great Proletarian Culture
Revolution (1966-1976), large-scale changes in land use from grazing to cropping oc-
curred several times. With the destruction of perennial vegetation the good stmcture
and the nutrition of the soil was quickly lost. In addition, many inappropriate efforts
for desertification control by conventional revegetation resulted in large areas of old
dwarf trees, unpalatable range vegetation and less productive and erodible farmland.
APPROACHES TO DESERTIFICATION REVERSION IN THE RANGELAND-
CROPLAND INTERLACED BELT
Strategies for desertification reversion
Through the above analysis of the causes of desertification it may be concluded that
under the heavy population pressure and the floundered land use structure it is impos-
sible to restore the steppe vegetation and the light grazing pasturage to its original
situation, and that conventional plantation alone is not sufficient in order to control the