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21A continuous, nonlinear model (FLOG-CN) linking carbon mineralization and nitrogen 22 mineralization-immobilization with respect to time was developed that successfully reproduced 23 the complex CO 2 -C and SMN dynamics for a collection of 70 paired C and N soil datasets. 24 Application of the model to diverse C and N datasets showed that incorporating latency into the 25 model of C mineralization, and using C to drive N dynamics, allows heterogeneous data from 26 many different soil amendments to be described by the same model. We successfully modelled 27 complex CO 2 -C and SMN dynamics of widely different shapes and from a variety of soil 28 amendments containing plant and animal residues. The re-interpretation of these datasets with 29 the FLOG-CN models improved the quantitative analysis of C and N dynamics, yielding new 30 insights into how amendment characteristics and experimental conditions influence the timing 31 and quantity of C and N mineralized. Model parameters were responsive to varying soil 32 characteristics (pH, C, N, C:N), amendment N:C, amendment rate, incubation temperature, and 33 N additions. Stepwise regression was used to predict model parameters using metadata available 34 for 56 of these datasets. Significant relationships were developed to estimate model parameters 35 independently using measured system properties or other model parameters that could be 36 independently estimated. Estimates of C and N dynamics both fell along a 1:1 line indicating that 37 the model parameters could be adequately described by the measured properties, but the 38 available metadata was not able to describe C dynamics with high precision. Nitrogen 39 mineralization-immobilization was strongly related to amendment N:C, and switched between 40 the two processes at an amendment N:C between 0.077 to 0.085 (C:N between 11.7 to 12.9). We 41 believe that the modelling approach described here will allow quantitative and objective 42 3 comparisons of diverse C and N datasets that have been hindered by subjective descriptions of 43 the past. 44 decomposition or mineralized in excess of microbial requirements, is expressed as SMN labile =

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Gillis, J. D., Price, G. W. and Stratton, G. W. 2014. Detection and degradation of organic contaminants in an agricultural soil amended with alkaline-treated biosolids. Can. J. Soil Sci. 94: 595–604. The agricultural use of wastewater biosolids is a common practice in many countries, but concerns exist regarding the presence of organic wastewater contaminants that remain in the land-applied biosolids. The objective of this study was to determine if contaminants present in biosolids are detectable in soil following land application. A suite of organic contaminants were monitored by gas chromatograph with mass spectrometer in agricultural soil samples from a site amended with increasing rates of alkaline-treated biosolids. Triclosan, a common antimicrobial agent, was detected at levels greater than the reporting limit in an environment-controlled incubation study and validated through in situ field samples from soils receiving the same alkaline-treated biosolid. A rapid decrease in triclosan concentration was observed during the first few weeks of the incubation study, with concentrations decreasing from 92±26 to 20±2 ng g−1 (average 78% decrease) after 4 mo. The field results indicate that triclosan in fall-applied may persist overwinter. However, a rapid decrease in triclosan concentration during the spring and summer months led to levels lower than predicted following the spring application, and levels below our reporting limit (up to 85% decrease) by the end of the study. Removal is posited to be through aerobic microbial degradation.