004160000a22001450004500020001500000060000800015082001900023100002100042245003200063260003100095260000900126300001100135490001100146650011300157  a0120007703  a100  a630.685 AGR.70  aSparks, Donald L  aAdvances in Agronomy Vol 70  aCalifornia, Academic Press  c2001  axi 369  a70c70  aDesertified Land, Carbon sequestration, Human nutrition,Nitrogen cycling, Methane Emissions, Organic farming