earticle

영어

The Setouchi Region, which is located on the seaward side of Matsuyama City in Ehime Prefecture, Japan, is potentially vulnerable to a substantial tsunami that could be induced by a future Nankai earthquake. To reduce the potential damage from such a tsunami and assure time for evacuation, local residents have constructed coastal disaster prevention forests along the coast in cooperation with members of Matsuyama rotary club since 2012. To build these forests, Pinus thunbergii seedlings were planted and jellyfish (Nemopilema nomurai) chips were applied as a soil amendment fertilizer. This study aimed to evaluate the effectiveness of jellyfish chips on the survival and growth of P. thunbergii seedlings in a coastal area based on a 5-year field investigation. Seedling mortality rate was significantly lower in the treatment (3.8%) than in the control (25.0%) plot in 2012 indicating the potential effectiveness of the jellyfish chips. Furthermore, the 5-year increase in height was significantly greater in the treatment (3.41 m) than in the control (2.32 m) plots in 2017 (p < 0.01). This trend for height increase was also observed in another section of the forest that was planted in 2013. These results revealed that jellyfish chips can contribute to improving soil condition by contributing to soil moisture retention during the early growth stage and supplying nutrients to the seedlings over time. Our findings indicated that jellyfish chips can be used effectively as an organic fertilizer for the construction of coastal disaster prevention forests.