再生水分根交替滴灌对马铃薯根-土系统环境因子的影响研究

分根交替(PRD)滴灌技术是很有节水潜力的灌水技术.利用再生水,采用分根交替滴灌技术对马铃薯根长密度、根重密度及土壤水盐的空间分布影响进行了研究.结果表明,马铃薯根系主要分布在0～60 cm的土层内,以植株为中心,呈放射状沿不同方向减小.通过研究所建马铃薯根长密度的空间分布函数能较好地反映根系的三维分布趋势.PRD灌溉可以刺激马铃薯根系生长,水分利用效率提高39%.进行PRD灌溉时应重点考虑滴头位置处及垄坡上的水盐变化,最好能起到节水控盐的双重作用.再生水PRD地下滴灌是对传统地表滴灌的优化和提升.

Effect of Partial Root Zone Drying Subsurface Drip on the Environmental Factors of Potato Root-soil System by Reclaimed Water Irrigation

Partial root zone drying (PRD) subsurface drip irrigation is a very potential water-saving technique. The effect of PRD subsurface drip irrigation on spatial distributions of potato root length density(RLD), root weight density(RWD), soil water and soil salt was studied by using reclaimed water. The results showed the soil layer of 0～60 cm was the main root layer of potato, the roots decreased and kept emission in different direction around the plant. The spatial distribution function of potato root length density could simulate the root distribution trend in 3D coordinate. PRD subsurface drip irrigation stimulated potato root growth and root density. Irrigation water use efficiency was increased by 39% under PRD subsurface drip irrigation. Soil water moisture and salt of emitter and middle of ridge slope should be taken into account by PRD irrigation in order to save irrigation water amount and control salinity. Water saving and salinity controlling were the dual-goal in PRD subsurface drip irrigation.