The Use of Isotopic Techniques to Quantify the Potential Contributions of Legumes to the Mitigation of Climate Change and Future Food Security

摘要

The large number of diverse legume species used to produce food for humans and livestock hold considerable promise as a means of adaptation to climate change. Legume systems have also been implicated as effective means of mitigating climate change through reductions in emissions of greenhouse gases such as carbon dioxide (CO2) from fossil fuels and nitrous oxide (N2O) from soil, and by accelerating soil carbon (C) sequestration. However, predicting how elevated concentrations of carbon dioxide (e[C0_2l) and future climates will affect soil nitrogen (N) cycling, soil C accretion and productivity in legume based farming systems remains a challenge. This paper identifies a number of opportunities where the isotopes of N and C could be applied to provide information on the key interaction between e[CC>2] and climate variables on the capacity for legumes to fix atmospheric N2, influence the above and below ground allocation of C and N, and change the C and N dynamics of soils.