Monitoring Agricultural Drought in Australia - Monitoring and Predicting Agricultural Drought: A Global Study - page 372

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quantity of wheat sold per farm declined by 45% (Bureau of Agricultural
Economics, 1983). The net value of rural production in Australia during
1982-83 was 50% lower than the average of the previous five years (Bu-
reau of Agricultural Economics, 1983), and there was an estimated overall
reduction in cash operating surplus of 57% across all Australian farms
(Purtill et al., 1983).
In extensive grazing lands, drought has led to high mortality of livestock
and widespread deterioration of the land and pasture resources. Livestock
losses during drought were highest during the first half of the 20th century,
as illustrated by annual changes in livestock numbers in Queensland's
grazing lands (figure 29.3), a major region of beef and wool production.
The dramatic stock losses that occurred in Queensland during the pro-
tracted drought from 1895 to 1902 (figure 29.3), for example, should no
longer occur due to an improvement in water supplies and transport sys-
tems for livestock, the use of more drought- (and tick-) resistant Bos indi-
cus cattle, and the improved options for supplementary feeding. Through
such technological advances, increased stock numbers are now possible
both in dry and wet periods. High grazing pressure (before, during, and
after the drought occurrence) has led to reduction in pasture cover, accel-
erated soil loss, decline in pasture composition, and fewer opportunities
to burn pasture. Pasture burning improves pasture quality and limits the
infestation and expansion of weeds, including woody plants (Tothill and
Gillies, 1992).
Despite the increasing value of agricultural production in Australia, di-
versification of the economy has caused the importance of agricultural pro-
duction to decline in relative terms, reducing the impact of drought on the
Australian economy. For example, the severe drought of 1982-83 resulted
in a decline in agricultural output of approximately 24%, but only ac-
counted for about one-half of the 2% decline in economic growth recorded
in that year. A 1% decline in economic growth is nonetheless significant
and, if forecast, could be mitigated to some extent by relaxing monetary
policy to maintain growth targets. Other ways in which governments plan
for and respond to drought are considered in the following section.

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Fig ure 29.3 Annual change in reported livestock (sheep and cattle) numbers in Queensland
(bars) and percentile summer rainfall for the region (inset) in which the majority (83%) of
livestock now occur.