Crop Types in Tokachi, Hokkaido.

[摘要] There are three crop types in Tokachi, Hokkaido. Naked barley and flax are in the first crop type, rice, corn and legumes in the second type and sugarabeets and cereals in the fifth type. The climatic type of Tokachi is BC'b and that of Aomori prefecture BC'a. The same latitude in the continental locations differ in the precipitation effectiveness index (after C. W. Thornthwaite) as B to C. The type of the northern, middle and southern part of the continental regions are respectively CC'b, CC'a and CC'a'. Four crops such as rice, barley, soybeans and sugarbeets show the same crop type without the difference of the precipitation effectiveness index. Two crops such as rice and soybeans show the same crop type regardless of the difference of mean temperature of the hottest month (after W. Koppen). The highest value of summation of the correlation coefficient between crop yields and monthly meteorological data is shown by the temperature in these six crops-rice, wheat oats, soybeans, small red beans and sugarbeets ; by the hours of sunshine in five crops-naked barley, field beans, peas, potatoes and flax and by the amount of rainfall in two crops-barley and corn. Naked barley and corn in May, rice, wheat, soybeans, small red beans, potatoes and flax in June, barley and peas in July, oats and sugarbeets in August and field beans in September show the monthly highest value of summation of the correlation coefficient. We can predict the yield of rice from June to August ; of oats from July to August ; of soybeans from June to July and of sugarbeets from July to September. In another crops we can also predict the yield by the highest monthly value of the correlation coefficient.

[学科分类] 农业科学（综合）