00293nam a2200109Ia 4500008004100000082002000041100002100061245003000082260003600112650001800148650001700166220204s9999    xx            000 0 und d  a631/635bADV.81  aSparks, Donald L 0aAdvances in agronomy V.81  aAmsterdambAcademic Pressc2004  aGlobal impact  aSoil erosion