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Drilling mud systems are used by the petroleum industry to facilitate and expedite the drilling of oil and natural gas wells. In western Canada, spent water-based muds (WBM) are often applied to cropland and native prairie at low application rates as a disposal option. We speculate that application of drilling waste on native prairie in semiarid climates will alter the soil surface energy balance and adversely affect soil biophysical processes and subsequently ecosystem productivity. This study was initiated to examine the effect of application rate (0, 40, and 80 m3 ha-1) of summer-applied WBM on surface albedo (α), soil temperature, and soil heat flux at the 0.05-m depth (G005) and at the surface (G) over 42 d following application. Our results provide evidence of a significant alteration of these micrometeorological parameters with WBM application. Surface albedo decreased by 15% (relative to the control) with the application of 40 m3 ha-1 mud and by an additional 3% when this mud rate was doubled. The lower α meant that a greater proportion of incoming shortwave solar radiation (Rsi) was available for partitioning into components of the surface energy balance, including C. This coincides with observed increases in G005, G, and soil temperature at the 0.025-m depth, with higher WBM. By modifiying heat flow and temperature in the root zone, WBM application may alter critical ecosystem biophysical and physiological processes, with important implications for overall biological productivity. The direction and magnitude of such changes, in conjunction with all the other ecological effects of WBM, will ultimately define the sustainability of the practice in this fragile ecosystem. [ABSTRACT FROM AUTHOR]

This article discusses the composting of different bedding materials used in feedlots in Alberta, Canada. The authors compared the chemical and physical properties of wood chip bedded manure with barley straw bedded manures. The found the temperatures were about the same but wood chip composts showed significantly lower nitrogen losses and lower total phosphorus as well as significantly higher total carbon and inorganic nitrogen. They encourage the adoption of wood chips over straw as preferred bedding for Alberta beef cattle feedlots.