Science in Practice Portal

Differences in annual runoff and soil loss caused by livestock grazing on arid rangelands can be measured directly from large plots. A low-cost monitoring tecnnique is described which uses rectangular plots, collection tanks, and cumulative mechanical stage-neight counters. Annual runoff and soil loss are measured on paired grazed and ungrazed plots. The plots are replicated and the pairing provides a control. Thus the statistical validity of any differences between grazed and ungrazed plots can be assessed. The plots are easy to construct, and can be maintained with as few as one to two visits per year. The system is presently being tested at four separate locations.