Locational and ecological analysis regarding the ill-drained paddy farming system that had been practiced until the prewar period in the northern part of Boso

Abstract

I discussed the ill-drained paddy farming system that was used from the modern age until the prewar Showa era in the northern part of Boso Peninsula. In ill-drained paddy field in Shimousa district during the Edo era, the Indica-type rice called Tomomi was broadly cultivated by "Tsumita" (direct sowing in a flooded paddy). Tomomi was cultivated in a heavy ill-drained paddy field of muck soil / peat soil called "Taito-tsuchi". When Japonica-type rice was cultivated by transplanting in "Taito-tsuchi" paddy, its growth was significantly restrained to result in heavy "natsuochi / akiochi". Direct sowing in a flooded paddy is a cultivation method utilizing the oxidative surface soil layer. The cultivation method was related to the plant type of Tomomi. In paddy field where "natsuochi / akiochi" was moderate, dense planting of small seedlings was performed until the pre-war Showa era. Dense planting of small seedlings was a cultivation method to secure the number of ears in ill-drained paddy fields where drainage and growth control were difficult. The ill-drained paddy farming system remained until the prewar period in the Shimousa district where land improvement had been delayed.