Study on the Number and Placement for Moisture Monitoring Sensor in Lettuce with Substrate Cultivation

摘要

A continuous monitoring tests for substrate moisture content were carried out in different depths of lettuce field under drip irrigation in greenhouse. Based on the observation data of the moisture probes laid at fixed points, the correlationship between substrate water content in different depths were analyzed, a better method for installing water monitoring points in substrate profile under drip irrigation is selected by R type hierarchical clustering method. Comprehensive analysis the substrate physical properties and the activity root zone of lettuce showed that the moisture sensors buried in 5 and 15 cm for monitoring the substrate moisture content in the depths of 0~15cmwere reasonable.