干湿交替对作物根际特征及铁膜形成的影响研究进展

铁膜普遍存在于水生植物的根系表面,根际周围Fe~(2+)的浓度和根系氧化力决定了根表铁膜的数量。干湿交替是农业生产中常用的灌溉技术。在干湿交替过程中,水分和氧气含量的变化导致根际土壤发生一系列物理、化学和生物学变化,从而对根表铁膜的形成产生影响。本文综述了干湿交替过程对根际特征变化的影响,分析了根表铁膜的形成条件、化学组成与空间结构和根表铁膜的形成过程,并在此基础上探讨了干湿交替对铁膜形成的影响以及干湿交替诱导铁膜形成的可能机制。最后对干湿交替诱导铁膜形成的研究方法与应用前景进行了展望。

Impacts of Drying-wetting Cycles on Changes of Rhizosphere Characteristic and the Formation of Iron Plaque: A Review

Iron plaque commonly forms on the surface of hydrophytes roots. The amount of iron plaque on the root surface depends on rhizosphere Fe₂₊ concentration and rhizosphere oxidative capacity. Alternate drying and wetting technique has been widely used in the agriculture production. During the processes of drying and wetting, variations of soil moisture and oxygen content would result in changes of soil physical, chemical and biological properties in the rhizosphere, which influences the formation of iron plaque. Impacts of drying-wetting cycles on rhizospheric characteristics were summarized in this paper. The chemical components and spatial structure of iron plaque were investigated on the root surface. The process of iron plaque formation and its affecting factors were also discussed. Based on the above results, the possible mechanisms of iron plaque formation were explored in response to drying-wetting cycles. Finally the methods for studying iron plaque formation and its application were prospected as affected by drying-wetting cycles.