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A 3-yr study, initiated in 1996, evaluated the availability of N from applied biosolids for dryland forage grass production under the cool, continental climatic conditions in central British Columbia. Treatments included 600 (LB), 1200 (MB) and 1800 (HB) kg total N ha−1 applied as municipal biosolids, a single application of 150 kg N ha−1 as urea in the first year of the experiment (SF), a multiple application of 150, 60 and 30 kg N ha−1 as urea in the first, second, and third years of the experiment (MF), and a control that received no biosolids or urea. All treatments were roto-tilled to 15-cm depth and seeded to a mixture of four grasses. The LB treatment was predicted to supply a similar quantity of plant-available N as the MF treatment, assuming 25, 10, and 5% of biosolids N is available in the first, second, and third year, respectively. Soil N fertility was poor as indicated by the very low forage yield and N uptake in the control, and minimal apparent net soil N mineralisation. Recovery of urea N in the crop over 3 yr averaged only 27%, likely reflecting net immobilisation in this recently broken site and accumulation of N in non-harvested portions of the crop. Cumulative recovery of N from biosolids in the harvested forage averaged only 11%. However, the fertiliser N equivalency of the biosolids N (ratio of recovery of biosolids N to urea N) was estimated at 41%, close to the predicted value of 40%. Forage yield and N uptake were similar for the LB and MF treatments, suggesting that actual biosolids N availability was similar to that predicted. Limited forage yield increase for the HB compared with the MB treatment early in the experiment, and high forage nitrate content for the HB treatment in the first year, suggest that the HB treatment initially supplied an excessive quantity of N. Both urea and biosolids applications increased cumulative uptake of other macro- and micro-nutrients, with forage Cu concentrations reaching values in the establishment year that may be of concern for some animal species. Monitoring of forage NO3 and Cu concentrations is advisable where biosolids are applied. Key words: Phleum pratense L., Dactylis glomerata, Bromus inermis, Bromus biebersteinii, soil N mineralisation, NO3 toxicity

Heavy metal environmental pollution which occurs as a result of lime contaminated with cadmium (Cd) poses a potential health hazard. This investigation was undertaken to study uptake of Cd by strawberry plants grown in soil amended with three different sources and two different rates of industry waste lime containing 3.4, 14.3, and 60.0 mg Cd/kg, respectively. The effects of Cd applied to the soil were investigated, including its distribution in the soil and effect on Cd concentration in strawberry cv. Senga Sengana (Fragaria anassa) leaves and fruit in response to soil organic matter content and lime rates. Cadmium accumulated mainly in the plough layer, increasing from 0.170 mg Cd/kg (background level) to a maximum of 1.2 mg Cd/kg. Fruit had very high, hazardous Cd concentrations regardless of its content in the soil. This indicates that Cd was easily taken up by strawberry plants and accumulated in upper plant parts, including the fruit. Soil Cd content had no effect on concentration of this e...