Management of trickle irrigation for banana: Hydrodynamic processes and sensor placement at the root zone

ABSTRACT Information on soil hydrodynamic processes assists in explaining the soil-water-plant relationship and has practical applications to irrigation management, such as the definition of soil water sensor placement. The objective of this study was to detail the hydrodynamic process in the soil root zone and to define the location for placement of soil water sensor under different configurations of trickle irrigation in banana crops. Three micro-sprinkler emitters with flow rates of 70 (T1), 53 (T2), 35 L h-1 (T3), and two drip system, one with one drip line per row of plants (T4), and another with two drip lines per row of plants (T5) were evaluated. The experiment was conducted in a randomized block design with five repetitions. Higher water extraction was found for irrigation systems with higher flow rates for all configurations of trickle irrigation systems. Soil moisture sensors in drip systems should be placed at distances of 0.75 to 0.81 m from the pseudo stem and at depths of 0.33 to 0.44 m. Under micro-sprinkler systems, soil water sensors should be placed at 0.75, 0.77 and 0.83 m from the pseudo stem towards to the emitter and at depths of 0.33, 0.48 and 0.55 m for emitter flow rates of 35, 53 and 70 L h-1, respectively.摘要：土壤水动力过程（soil hydrodynamic processes）相关信息有助于阐释土壤-水-植物三者间的关联，并在灌溉管理领域具备实际应用价值，例如用于确定土壤水分传感器（soil water sensor）的布设位置。本研究旨在明晰香蕉种植园滴灌（trickle irrigation）不同配置模式下的土壤根区水动力过程，并确定土壤水分传感器的布设位置。本试验共评估了3种流量分别为70（T1）、53（T2）、35 L·h⁻¹（T3）的微喷灌喷头（micro-sprinkler emitters），以及2种滴灌系统：一种为每行作物布设1条滴灌带（T4），另一种为每行作物布设2条滴灌带（T5）。本试验采用随机区组设计（randomized block design），设置5次重复。试验结果表明，所有滴灌配置模式中，流量更高的灌溉系统的水分提取量均更高。滴灌系统中的土壤水分传感器应布设于距假茎（pseudo stem）0.75~0.81米、深度0.33~0.44米的位置。在微喷灌系统中，针对流量分别为35、53、70 L·h⁻¹的喷头，土壤水分传感器应沿朝向喷头的方向布设于距假茎0.75、0.77和0.83米处，埋设深度分别为0.33、0.48和0.55米。