Many perceived agricultural droughts are related to forage shortages which should be recognized as carrying
capacity crises caused by inappropriate stocking policies (Robinson 1982, Dankwerts and King 1984).
Numerous studies support the general conclusion that there are no significant differences in infiltration rates or
soil loss between similar ungrazed and moderately grazed rangelands (cf., Thurow 1991). However, heavy
grazing results in reduced infiltration and accelerated erosion. The quandary is that moderate grazing rates
are, in practice, calculated on the basis of expected production from a site. During an agricultural drought, the
physiological needs of forage plants are not met and production rapidly declines. The result is that rangelandsstocked at a moderate rate based on long-term experience may actually be heavily stocked based on
physiological condition of plants during a dry period. Physiological stress may occur more quickly if the
vegetation has low energy reserves as a result of having been subjected to intense grazing pressure prior to a
dry period. The amount, vigor, and quality of vegetation is correlated with the condition of the range. Therefore,
agricultural drought on sites in poor condition is likely to be manifest more frequently and more severely than
on sites in good condition
Many perceived agricultural droughts are related to forage shortages which should be recognized as carrying
capacity crises caused by inappropriate stocking policies (Robinson 1982, Dankwerts and King 1984).
Numerous studies support the general conclusion that there are no significant differences in infiltration rates or
soil loss between similar ungrazed and moderately grazed rangelands (cf., Thurow 1991). However, heavy
grazing results in reduced infiltration and accelerated erosion. The quandary is that moderate grazing rates
are, in practice, calculated on the basis of expected production from a site. During an agricultural drought, the
physiological needs of forage plants are not met and production rapidly declines. The result is that rangelandsstocked at a moderate rate based on long-term experience may actually be heavily stocked based on
physiological condition of plants during a dry period. Physiological stress may occur more quickly if the
vegetation has low energy reserves as a result of having been subjected to intense grazing pressure prior to a
dry period. The amount, vigor, and quality of vegetation is correlated with the condition of the range. Therefore,
agricultural drought on sites in poor condition is likely to be manifest more frequently and more severely than
on sites in good condition
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