Rangeland Conservation Practices
Soil and Water Effects
444. Assessing the impact of overgrazing on soil
erosion in arid regions at a range of spatial scales.
Sharma, K. D.
In: Human impact on erosion and sedimentation/ Walling,
D. E. and Probst, J. L.; Series: IAHS Publication 245.
Oxfordshire: IAHS Press, 1997; pp. 119-123.
Notes: ISBN: 0901502309; Conference: 5. Scientific
Assembly of the International Association of Hydrological
Sciences (IAHS), Rabat (Morocco), 23 Apr-3 May 1997
Descriptors: grazing/ soil erosion/ arid lands/ assessments/
erosion rates/ scaling/ spatial distribution/ livestock
Abstract: Increased livestock numbers in arid regions
cause overgrazing which results in reduced infiltration and
accelerated runoff and soil erosion. Results from a range of
studies indicate that at the macro- and mesoscales soil
erosion can increase dramatically due to overgrazing;
causing increases of five to 41 times over the control at the
mesoscale and three to 18 times at the macroscale.
However, the establishment of simple relationships across
the range of scales is difficult due to spatial variation of soil
erosion rates and patterns. Water authorities should be
actively associated with range management activities for
the protection of arid zone drainage basins.
445. Association of herd composition, stocking rate,
and duration of calving season with fecal shedding of
Cryptosporidium parvum oocysts in beef herds.
Atwill, Edward R.; Johnson, Eileen M.; and Pereira, Maria
Das Gracas C.
Journal of the American Veterinary Medical Association
215(12): 1833-1838. (1999)
NAL Call #: 41.8 Am3; ISSN: 0003-1488
Descriptors: calving season/ herd composition/
reproductive management/ rotational grazing practices/
Abstract: Objective: To evaluate the association of herd
demographics, parturition variables, stocking rate, and
rotational grazing practices with the probability of fecal
shedding of Cryptosporidium parvum from beef cow-calf
herds in Califo