Off-stream watering troughs may reduce surface water pollution by shifting nutrient distribution from natural watering sites along the river to around artificial water troughs some distance from the river. The objective of our study was to evaluate the suitability of nine soil properties for assessing the impacts of cattle activity adjacent to eight watering sites. Nine surface (0-5 cm) soil properties were evaluated along four 100-m transects at the five off-stream water troughs and three river access sites along the Lower Little Bow River in southern Alberta over 4 yr (2007-2010). The properties included P (total P, soil test P or STP), N (total N, NO3-N, Nal-N), total C, total C:total N ratio (TC:TN), chloride (Cl), and soil bulk density. Soil test P was significantly (P <= 0.05) enriched at 65% of site-year comparisons, followed by total C (63%), NO3-N (55%), total P and TC:TN (50%). This suggested that these soil properties were relatively good indicators of cattle activity at the majority ( >50%) of watering sites. Chloride was a valid indicator only in non-saline areas (100% of four non-saline sites). Total C and TC:TN ratios were not valid indicators in the calcareous soils at all sites because of possible confounding influence of inorganic C. Overall, we recommend Cl as an indicator of cattle activity at watering sites not affected by soil salinity and high natural Cl levels, and STP as the best overall indicator of cattle activity at off-stream watering sites and river access sites. Certain soil properties were also influenced by distance from watering site, stocking rate, precipitation, and age of water trough.
