马铃薯覆膜方式对土壤氮磷钾养分与产量的影响

针对宁夏南部山区马铃薯覆膜种植的特殊环境,通过田间试验研究了不同覆膜方式下土壤氮磷钾养分及马铃薯产量变化特征。结果表明,与露地种植相比较,随着马铃薯生育期的延长,全膜覆盖种植表层(0~20 cm)土壤有机质和有效磷具有累积现象,半膜种植表层(0~20 cm)土壤全氮和碱解氮含量较高,但对下层(20~60 cm)土壤有机质、全氮、碱解氮和有效磷含量影响较小,无论是马铃薯全膜种植还是半膜种植均对土壤速效钾含量影响较小,甚至略有降低,其中半膜种植降低最为显著,降幅达47.3 mg/kg。与露地相比较,覆膜种植可显著增加马铃薯产量,其中马铃薯全膜种植单位面积产量最高,达50 609 kg/hm~2,而马铃薯半膜种植由于受后期降雨的影响,烂薯较多,对产量造成较大影响。因此,马铃薯在生长后期降雨充沛的情况下可考虑揭膜管理措施。

Effects of different film-mulching methods on soil nitrogen,phosphorus,potassium nutrients content and the potato yield in dry land

According to the special condition of film-mulching cultivation for dry land potato in the southern mountain areas of Ningxia,a field experiment was carried out to investigate the change characteristics of soil nitrogen,phosphorus,and potassium nutrients content,and potato yield under different film-mulching methods.The result indicted that,compared with traditional open field cultivation,soil organic matter and available phosphorus were accumulated in topsoil of 0～20 cm with the development of potato growing period under full-mulching method,and soil total nitrogen and available nitrogen contents in topsoil of 0～20 cm under half-mulching method were higher than other treatments,but there were less effects on soil organic matter,total nitrogen,available nitrogen,and available phosphorus contents in subsoil of 20～60 cm.Soil available potassium content was slightly decreased with full-mulching and half-mulching methods,it was decreased by 47.3 mg/kg under half-mulching method.Potato yield with film-mulching was significantly increased in contrast to traditional open field cultivation,and the highest potato yield was 50 609 kg/hm2 with full-mulching method.However,because of much more rainfall in the later growing period of potato,there were a lot of rotten tubers under half-mulching method,which seriously influenced on its yield.Therefore,it should be considered film mulching uncovering when the rainfall was abundent during the later growing period of potato in the dry land in the southern mountain areas of Ningxia.