Analysis of agricultural field and area for large-sized re-consolidation of paddy field.

1963年开始的土地整理工程，将40%的稻田调整为100m×30m的矩形，进入灌渠和排水渠。而一些已经调整过的土地被重新整合成大型农田，使之规模化存在一些需要解决的问题，如核心农户的种植权集中方法，土地平整的严密性等。为此，调查人员分析了新近巩固的大比例尺田块和网格数据库三个模型场，诺吉里地区的200m×40m田块变成了较小的地块，其长边长度小于200m，划分单位与替代地块相同。随后，排水渠的通达性下降，需要增加排水渠的建设。水间小区的长边长度也是200m，但长边和短边都设有两用渠，将田块分割成较小的地块时，不需要额外修建排水渠。高州和州区长边的长度为125m，没有进行分割，反而为了提高工作效率进行了地块的捆绑。关东地区60%的水田可整合为大面积水田，近60%的水田可推广积水直播技术，25%的水田可推广旱作直播技术，提出了在不同地理位置和耕作方式下适宜的小区规模和灌排方式。

Land consolidation project started 1963 has adjusted 40% of paddy field into 100m x 30m rectangular shape, accessing irrigation ditch and drainage canal. And some of the already adjusted field is re-consolidated into large-sized field.Making large-sized field has some problems which should be solved, such as method of concentration of cultivation right to core farmer, and preciseness of land levelling. So, the investigators analyzed three model fields, recently consolidated large-sized field, and mesh data bases.200m x 40m field of Nojiri district have changed into smaller plots whose length of longer side is less than 200m and unit of division is same as substitute lot. Then accessibility to drainage canal had decreased and additional constructions of drainage canal became needed. Length of longer side of Mizuma district is also 200m, but dual-purpose canal is equipped along both longer and shorter sides, so additional construction of drainage canal was not needed when the field was divided into smaller plots.Length of longer side of Takasu-waju district is 125m and division was not occurred, on the contrary, binding of plots has been happened for increasing working efficiencies.The results of mesh data analysis are as follows;60% paddy field of Kanto area can be consolidated into large-sized field, and technique of direct seeding in ponding condition can be introduced in almost of 60% field, and that in dry condition can be introduced in 25% of paddy field with those conditions.In conclusion, the fittest plot size and method of irrigation and drainage are pointed out in condition of location and farming style.