Sequestering soil carbon in the low input farming systems of the semi-arid tropics – does litter quality matter?A MWhitbreadauthorRLefroyauthorGBlairauthorYKonboonauthorKNaklangauthorMaintaining soil organic matter (SOM) in low input smallholder rice cropping systems worldwide is of paramount importance to maintaining livelihoods and food security. A long term rainfed lowland rice experiment tested the hypothesis that applying small (1.5 t/ha dry matter) annual additions of slowly decomposable plant materials which were grown offsite and applied prior to land preparation, could result in increased soil organic carbon, crop yield and improve the recovery of nutrients compared with plant materials of higher quality or straw retention alone. Annual leaf litter applications over 9 seasons resulted in significant increases in SOC of 39% (from 3.5 to 4.9 mg/g) in the leaf litter treatments compared to only 13 % in the noleaf litter control. In terms of rice grain production and nutrient use efficiency, leaf litter quality was an important driver. Apparent nutrient recovery of nitrogen and sulfur reflected the decomposition rate of the added residues. Sustainable farming systems will require that crop yields are stable through the maintenance of soil fertility and the balanced use of nutrients in the system. The results of this study are therefore highly significant and provide evidence that low rate, long term residue management can have profound effects.Semi-Arid TropicsFarming SystemsDrylands AgricultureSoil Science2017Conference or Workshop Item