Soil C Pool Management Index of Different Irrigation Methods in Protected Field

The experiment of different irrigation methods include furrow irrigation,drip irrigation and subsurface irrigation was conducted for a long term,and soils were sampled at different 3 depths within 45 cm,and determined the content of soil total organic carbon,active carbon and counted CPMI(carbon pool management index).The effect of different irrigation methods on total organic carbon and active carbon was studied in a protected field.The results indicated that the content of soil total organic carbon and active carbon were decreased with deeper layer.In 0 to 15 cm and 15 to 30 cm soil layer the order of soil total organic carbon was drip irrigationsubsurface irrigation furrow irrigation,and 30 to 45 cm soil layer the order of soil total organic carbon was subsurface irrigation drip irrigationfurrow irrigation.Different soil layer soil active carbon order was subsurface irrigationdrip irrigationfurrow irrigation,and the content of soil active carbon in 30 to 45 cm soil layer subsurface irrigation treatment was significantly higher compared to furrow irrigation treatment at the 5% level.CPMI order of different irrigation methods and different soil layers was subsurface irrigationdrip irrigationfurrow irrigation,none but in 15 to 30 cm soil layer subsurface irrigation treatment and drip irrigation treatment were significantly higher than furrow irrigation treatment for CPMI at 5% level.