阴山北麓马铃薯在不同灌溉模式下的水肥效率

为明确内蒙古阴山北麓马铃薯主产区不同灌溉模式对水肥利用效率以及土壤无机氮残留的影响,2009—2010年进行了漫灌(农民习惯)、喷灌、露地滴灌、膜下滴灌4种灌溉模式对比研究,分析了不同灌溉模式对马铃薯产量形成、水分利用效率、养分偏生产力、经济净收益以及土壤无机氮残留的影响。结果表明:膜下滴灌马铃薯的产量、水分利用效率、氮磷钾肥料的偏生产力以及经济净收益均显著高于其他3种灌溉模式。其中,膜下滴灌的马铃薯产量分别比漫灌、喷灌和露地滴灌增加35.7%、26.0%、12.9%,水分利用效率和经济净收益分别增加200.2%、91.8%、23.7%和37.7%、30.1%、10.7%;氮肥偏生产力膜下滴灌比漫灌、喷灌和露地滴灌分别增加50.6 kg.kg 1、39.8 kg.kg 1、22.0 kg.kg 1,磷肥偏生产力分别增加126.6 kg.kg 1、99.4 kg.kg 1、55.0 kg.kg 1,钾肥偏生产力分别增加42.3 kg.kg 1、33.2 kg.kg 1、18.4 kg.kg 1。漫灌马铃薯收获后60~120 cm土层无机氮残留量达102.95 kg.hm 2,分别是喷灌、露地滴灌和膜下滴灌的1.36倍、2.11倍和2.28倍。由此可见,露地滴灌和膜下滴灌不仅节水,且马铃薯高产、养分资源和经济高效,可显著减少薯田氮素淋洗,从而降低环境污染的风险。

Water and fertilizer use efficiency of potato under different irrigation patterns in North Yin Mountain Region

The North Yin Mountain Region (NYMR), the main potato production region in Inner Mongolia, is highly limited in water resources. Water-saving cultivation techniques have therefore been increasingly used in this region in recent years. To evaluate the effects of different irrigation methods on water and nutrient use efficiency and the eco-environmental benefits of potato cultivation, field experiments were conducted in 2009-2010 in the Wuchuan Region of NYMR, Inner Mongolia. The field experiment was consisted of four different irrigation patterns - flood irrigation (FI), ground sprinkler (GS), drip irrigation (DI) and under-mulch-drip irrigation (UMDI). The irrigation patterns were compared in terms of potato tuber yield, water and nutrient use efficiency, net economic income and soil inorganic nitrogen residue. The results showed that UMDI increased potato yield over conventional farm practice FI, GS and DI by 35.7%, 26.0% and 12.9%, water use efficiency by 200.2%, 91.8% and 23.7% and net economic income by 37.7%, 30.1% and 10.7%, respectively. Nitrogen fertilizer partial factor productivity under UMDI was respectively 50.6 kg·kg^-1, 39.8 kg·kg^-1 and 22.0 kg·kg^-1 higher than those under FI, GS and DI. Also phosphorus fertilizer partial factor productivity under UMDI was respectively 126.6 kg·kg^-1, 99.4 kg·kg^-1 and 55.0 kg·kg^-1 higher than those under FI, GS and DI. Then potassium fertilizer partial factor productivity under UMDI was respectively 42.3 kg·kg^-1, 33.2 kg·kg^-1 and 18.4 kg·kg^-1 higher than those under FI, GS and DI. Soil inorganic nitrogen residue in the 60~120 cm soil layer after potato harvest was 102.95 kg·hm^-2 under FI, which was 0.36, 1.11 and 1.28 times higher than those under GS, DI and UMDI, respectively. The above results suggested that DI and UMDI not only saved water resources, but also enhanced potato yield, nutrient use efficiency and net economic income in the research area. This was critical for reducing the risk of environmental pollution due to nitrogen leaching. It was therefore important to intensify DI and UMDI irrigation patterns in potato fields in the NYMR for higher yields, resources use efficiencies and low environmental pollution risks.