This is an update on ROI #000502, Sam's paper has now been accepted: 
McNally, Samuel Rae, Laughlin, Daniel C., Rutledge Susanna, Dodd, Mike B., Six, Johan, Schipper, Louis A., 2015. Root carbon inputs under moderately diverse sward and conventional ryegrass-clover pasture: implications for carbon sequestration. Plant and Soil, 392, 1-2, 289-299