Evapotranspiration of Bell Pepper Grown with Cloud-Based Fertigation in Greenhouse.

A fertile surface layer of farmland was decontaminated and replaced by non-fertile soil in Fukushima since the accident of Fukushima Daiichi Nuclear Power Plant in 2011. We reported that liquid fertilizer was applied suitably as a result of the evaluation of changes in the volumetric water content in soil where was conducted a commercially-available cloud-based fertigation system (CBFS). The evapotranspiration and the volumetric water content (θ_w) of green pepper growth with CBFS were evaluated. We used Penman-method to estimate the evapotranspiration, representing transpiration since soil surface was covered with plastic mulch. We assumed wind speed was always 0.6 m s^-1. Time domain reflectometry (TDR) probes were used to monitor the changes in the θ_w. The evapotranspiration coincided with the amount of applied water. This result implied that the amount of applied water (liquid fertilizer) was suitable. The transpiration from the plant has to measured directly since we ignored the evaporation from the soil surface.