Fjölrit RALA - 05.12.1999, Blaðsíða 90

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Rangeland degradation in Northern China
whatever the cause, would be reduced. Rangeland restoration implies the increasing
grazing rate to a standard matching that which it originally had.
Rangeland degradation is the most extensive among the major types of current
landuse. Few countries have less than 50 percent of their pastoral lands degraded
(World Bank 1992). Overgrazing by livestock is the principal land problem in the arid
and semi-arid regions, coupled with landuse change to cultivated farmland in the
many countries short of farmland (Barrow 1991). The high percentage of the world’s
rangeland that suffers from over use stems frorn the extensive, low intensity character
of pastoral land use, the slow response to land management changes in arid climates,
and the social and economic problems associated with reducing livestock numbers on
heavily used rangelands (Narjisse 2000). Reducing populations of cattle, sheep, and
goats among people living on the margin of survival cannot be done without providing
other sources of livelihood and that is rarely available. China has a markedly higher
percentage of degraded rangelands than the countries in the same latitude, primarily
because of the heavier grazing pressure and the conversion to farmland (Jia 1995). In-
vestigations have shown that more than 70% of the Ordos grassland is degraded and
undergoing retrogressive succession. The community composition is being simplified,
good herbage species are being reduced, production is declining, and environmental
conditions are worsening.
The state and functton of the Ordos rangeland
Landforms and Iandscapes
Located at the northem part of China, the Ordos Plateau is bordered by the Yellow
River in the west and north, and the Loess Plateau in the south. The plateau can
clearly be divided into four parts according to landform and landscape; the Jungle
Loess Hills in the east, the Kubuqi and Maowushu Sandy Land stretching north to
south, the Wsheng Basin
in the center, and a dry
plateau in the west (Shi
1991). These four land-
forms and landscape
units are covered by tme
steppe of Stipa bung-
eána, shmbs of Artem-
isia spp., salt meadows
and marshes, and desert
steppe of Stipa brevi-
flora, respectively (Jia
1995). The great varia-
tion of landform and
landscape make the
plateau featured by a
higher ecosystem diver-
sity than most of the
other regions (Li 1995)
(Figure 1).