SIMULATION STUDY OF THE IMPACT OF PERMANENT GROUNDCOVER ON SOIL AND WATER CHANGES IN JUJUBE ORCHARDS ON SLOPING GROUND

Land degradation is recognized as a major environmental problem in rainfed fruit orchards on the Chinese Loess Plateau. Six treatments were used to investigate surface runoff and soil moisture by means of simulated rainfall experiments: (i) a control (clean cultivation) (CC); (ii) strip cock's foot (Dactylis glomerata L.) cover (SCF); (iii) strip crown vetch (Coronilla varia L.) cover (SCV); (iv) strip bird's foot trefoil (Lotus corniculatus L.) cover (SBF); (v) strip white clover (Trifolium repens L.) cover (SWC); and (vi) complete white clover cover (WCC). The time to runoff was significantly longer under WCC than under other treatments (p<0.05). The total runoff volume and sediment yield were significantly greater under CC than under the vegetation cover treatments (p<0.05). The mean infiltration rate under WCC and CC was the largest and lowest and differed significantly from that under other treatments (p<0.05). The change of soil water storage was the largest under WCC and the least under CC. The soil moisture was significantly greater under SCF than under other treatments (p<0.05). Treatment SCF seemed to be the best groundcover for rainfed sloping jujube orchards on the Chinese Loess Plateau. Copyright (C) 2014 John Wiley & Sons, Ltd.