【摘要】 为缓解残膜污染对棉田生态的影响,在新疆农垦科学院作物所1~2号试验地进行了棉田揭膜试验,研究头水后揭膜和2水后揭膜对土壤温湿度和棉花根系发育的影响,以期为新疆滴灌棉田揭膜工作的开展提供理论依据。本研究设置头水后(6月14日)和2水后(6月23日)揭膜两个处理,以正常覆膜为对照,连续测定头水后到灌溉结束棉田土壤温湿度的变化,同时测定棉花根系发育及干物质积累动态,成熟期进行产量测定。结果表明:7月5日之前,揭膜会降低土壤温度且幅度随着深度增加逐渐减少;4水前揭膜会降低土壤湿度,降低幅度随着浇水后天数增加逐渐变大。揭膜可促进棉花根系提前建成,增加干物质的积累量及侧根数的发生。揭膜处理地上部干物质积累线性增长期较CK缩短8.54~12.72 d,根系干物质积累时间缩短9.91~11.68 d。揭膜处理干物质积累量较CK增加12.34%和11.67%,产量较CK增加6.0%~8.3%。更多还原

【Abstract】 To relieve the ecological influence by pollution of membrane residual in cotton fields and study the feasibility of uncovering plastic film at a suitable time in cotton with drip irrigation in Xinjiang,an experiment was carried out to investigate the effects of plastic film uncovering on soil temperature,moisture level,and cotton root growth. The results could provide a theoretical basis for plastic film uncovering in the mulched drip irrigation cotton field. Three treatments,including uncovering film after first irrigation( June 14),uncovering film after second irrigation( June 23),and normal film covering( CK),were implemented. Soil temperature and moisture level were determined continuously from first irrigation to last irrigation. At the same time,the dynamic accumulations of dry matter and root growth were monitored and the yield was examined at the mature stage. When plastic film was uncovered after first or second irrigation,soil temperature before July 5th was decreased,and amplitude was minimized with the increase in depth. Moisture level before fourth irrigation was also decreased,and the reduction amplitude became increased with time. Plastic film uncovering could promote cotton root growth,improve weight of dry matter and number of lateral roots. Compared with CK,uncovering plastic film resulted in the linear period of aboveground dry materials growth shortened by 8. 54 ~ 12. 72 d,linear period of root growth reduced by 9. 91 ~ 11. 68 d,dry materials improved by 12. 34% ~ 11. 67% and yield increased by 6. 0% ~ 8. 3%.更多还原