Grazing affects the plant ecology and adds excreta, thereby influencing soil N relationships. Consequently, total N, mineralizable N, exchangeable N, hydrolyzable N, and urease activity were assessed at the Agriculture Canada Research Substation, Stavely, Alberta, in the Ah horizons on rough fescue (Festuca scabrella Torr.) grasslands stocked at either light (0.8 ha/AUM) or very heavy (0.2 ha/AUM) fixed rates for 38 years and in exclosures located within each field for an equal period of time. Even though total N expressed as t/ha per Ah horizon remained the same, changes in various N fractions were nevertheless evident. Grazing resulted in more NH4 +/- N and NO3-N in both fields at the time of sampling and each was greater at the higher stocking rate. Although soil N was less mineralizable, it was more acid-hydrolyzable at the higher stocking rate. Urease activity also increased. The effect on soil N characteristics of increased excreta loads is complex and still not well understood. This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries. The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact lbry-journals@email.arizona.edu for further information. Migrated from OJS platform August 2020
Scholarly peer-reviewed articles published by the Society for Range Management. Access articles on a rolling-window basis from vol. 1, 1948 up to 5 years from the current year. Formerly Journal of Range Management (JRM). More recent content is available by subscription from SRM.