新疆棉花膜下滴灌技术存在的问题及改进措施——双层可降解膜覆盖与地下滴灌技术结合应用探讨

Problems and Improvements of Plastic Mulched Drip Irrigation for Cotton Plantation in Xinjiang:Feasibility of Application for Combining Double Degradable Films Mulch with Subsurface Drip Irrigation

膜下滴灌技术便于机械化操作,且具有节水节肥等优点,因此在新疆地区得以迅速发展。然而,随着膜下滴灌推广面积的不断增加,一些在生产实际中普遍存在且亟待解决的问题逐渐暴露出来,如苗孔覆土裸露,低温天气条件下幼苗容易受到伤害,尤其是降雨过后表层土壤干燥结壳,阻碍幼苗生长、降低出苗率;大量地膜残留造成环境污染;地面滴灌条件下棉花根系总量少且分布浅,导致植株抗性弱、易早衰等。针对以上问题,在综合分析现有研究成果及实践经验的基础上,提出采用可降解膜进行双膜覆盖,并与地下滴灌技术相结合,对目前广泛应用的膜下滴灌技术模式进行改进,可提高出苗率,有效避免地膜环境污染和植株根系浅、抗性弱等缺陷,相关技术模式(如可降解膜覆盖方式及降解过程控制、合理灌溉制度的制定等)的实际应用有待进一步研究。

Plastic mulched drip irrigation technique(PMDIT)has been used widely in Xinjiang because of its high water and fertilizer use efficiencies,and feasible-to-be-mechanized operation in the field.However,lots of problems such as low emergence rate(resulted from the low temperature and soil crust near the film holes for the growth of cotton seedlings)。waste films pollution to the soils and weak adversity resistance(resulted from the shallow roots and high ratio of shoots and roots)were gradually found when using the PMDIT in the practical production.Based on analyzing and summarizing available research results and practical experiences,a technique,combining the double degradable films mulch with the subsurface drip irrigation,was put forward to solve the problems and improve the extensively used PMDIT at present in this study.Technique should be helpful for enhancing the emergence rate and adversity resistance ability of cotton,and reducing waste films pollution to the soils.However,some specific measures(for example,the mulching methods and determination of the degradation duration of the degradable films,and the rational irrigation schedule,etc.)related to the practical application of the technique need further research.