To reduce the nitrate leaching risk after potato （Solanum tuberosum L.） harvest and improve nitrogen fertilizer-use efficiency, a potato-cabbage double cropping system （DCS） was established at Hetao, North China, ...To reduce the nitrate leaching risk after potato （Solanum tuberosum L.） harvest and improve nitrogen fertilizer-use efficiency, a potato-cabbage double cropping system （DCS） was established at Hetao, North China, an arid area with irrigated land. A two-year field experiment demonstrated that planting early-maturing potato cultivar under plastic mulch shortened its growth period by 14 d and allowed a second crop of cabbage to scavenge the soil residual NO^--N to a depth of 160 cm, substantially reducing the risk of nitrate leaching into groundwater. The yearly total N uptake in DCS was about 110 kg ha-1 more than that in the conventional cropping system （CCS）, i.e., mono potato planting. This accounted for apparent nitrogen recovery （ANR） improvement of 16.90%-26.57% in the DCS as compared to that in the CCS for both years. As a result, the soil residual NO3-N in the 0-160 cm soil profile in the DCS was lower than that in the CCS. The solar energy-use efficiency and soil-use efficiency were also substantially increased with DCS.展开更多
基金Supported by the Inner Mongolia Agricultural University Innovation Team Foundation for Potato,China (No.NDPYTD2010-5)the Ministry of Agriculture Special Industry Foundation of China (No. 201103003)the Hong Kong Research Grants Council of China (No. HKBU 262809)
文摘To reduce the nitrate leaching risk after potato （Solanum tuberosum L.） harvest and improve nitrogen fertilizer-use efficiency, a potato-cabbage double cropping system （DCS） was established at Hetao, North China, an arid area with irrigated land. A two-year field experiment demonstrated that planting early-maturing potato cultivar under plastic mulch shortened its growth period by 14 d and allowed a second crop of cabbage to scavenge the soil residual NO^--N to a depth of 160 cm, substantially reducing the risk of nitrate leaching into groundwater. The yearly total N uptake in DCS was about 110 kg ha-1 more than that in the conventional cropping system （CCS）, i.e., mono potato planting. This accounted for apparent nitrogen recovery （ANR） improvement of 16.90%-26.57% in the DCS as compared to that in the CCS for both years. As a result, the soil residual NO3-N in the 0-160 cm soil profile in the DCS was lower than that in the CCS. The solar energy-use efficiency and soil-use efficiency were also substantially increased with DCS.
