CHINA’S WILD WEST - Wildlife Conservation in China: Preserving the Habitat of China's Wild West - page 35

during the year, by domestic livestock. Yet the condition and trend of western China's
grasslands are the subject of considerable debate despite the almost universal claim from
official Chinese sources that overgrazing and rangeland deterioration are serious and
widespread. Alas, as with many other crucial questions related to western China, reliable
data upon which to assess the various positions are scarce.
To begin, the terms “overgrazing” and “grassland degradation” are often poorly
defined. What, exactly, is meant when these concepts are invoked? The two most com-
mon terms used in Chinese literature, both scientific reports and policy statements, are
chaozai (“exceed capacity”) in reference to livestock stocking rates and tuihua (“degrade,
deteriorate”) in reference to rangeland response. But lacking more specificity, neither of
these terms can be interpreted. A water tank has a clearly defined capacity: continue to
add more water after capacity is reached and it will simply spill back out. But this same
clarity eludes us when referring to a grassland ecosystem: there is no clearly demarcated
“capacity” below which more grazing pressure can be added and beyond which it spills
out. Rather, increased grazing produces quantitative or qualitative responses, and at certain
grazing levels, changes in plant composition or soil health may become so pronounced
as to become irreversible without external input and intervention. To reduce the problem
of grazing intensity into a simple dichotomy (below or above a defined “capacity,” i.e.,
“overgrazed” or not) is to lose sight of management objectives. If one's objective is to
retain species composition and abundance that allows for wildlife use as well as livestock
use, the grazing capacity will be different from that suggested if the management objec-
tive is merely to minimize soil erosion. 42
The term “degradation” avoids the categorization problem by suggesting a continuity
of states, implying that any given parcel may be relatively more “degraded” than another.
But it suffers from vagueness sufficient to render the term almost meaningless. If one could
begin with a parcel of rangeland entirely untouched by any herbivore, the introduction of
even a single plant consumer would begin to change the quantity and quality of vegeta-
tion. As more herbivores were added and more plant material removed, plant size, plant
vigor, and vegetation composition would all change as well. Clearly, rangeland plants
have evolved in the presence of herbivory, so such changes are not necessarily destruc-
tive to ecosystem function. 43 But would any such change merit the term “degradation”?
Certainly, there are grazing intensities that result in replacement of favored species by
unpalatable or poisonous species, by complete loss of plant species, and, in the extreme,
loss of soil productivity. By any standard, such rangelands deserve to be called “degraded.”
But variation from an idealized (if unnatural) ungrazed state to a completely unusable one
is continuous (or perhaps occurs via relatively rapid transitions among differing states 44 );
without quantitative data, there is no way to know where any parcel of land is on the
continuum. Alas, Chinese writing on range condition invariably avoids quantification,
instead leaping straight toward categorization and conclusion. 45
It is easy to find sources purporting to show how much, or how badly, Chinese grass-
lands have been “degraded,” but difficult to find documentation on what is meant or on
how the information was collected. Nationally, there are at least two quite disparate of-
ficial statistics regarding the magnitude of grassland degradation. One, issued in 1999