18. Rice Ecological System and Rice-Cropping Pattern 2
- INDEX -
Productivity of Each Ecological System and the Future Trend
Irrigated Lowland Rice
Rain-fed Lowland Rice
Upland Rice
Floating Rice
Necessity of Irrigation
Rice-Cropping Patterns
Rice-Cropping Pattern
Rice-Cropping in India
Rice-Cropping in Tanzania
Special Planting Pattern
Productivity of Each Ecological System and the Future Trend
Irrigated Lowland Rice
The Table 7 shows the yield of irrigated, rain-fed, and upland rice in the Philippines, as an example. Needless to say, irrigated rice-cropping shows the highest yield. In Japan, Korea and China, the ratio of irrigated rice-cropping is almost 100%, with a by far greater yield than that of tropical countries. There is a considerably high correlation between the rate of irrigated rice-cropping and rice yield among the 15 states in India (r=0.863***, Fig 1).
Upland Rice
As is the case with rain-fed, the upland rice is also quite unstable and its yield is very low. Upland cropping is dictated by water conditions and is vulnerable to weed damage. For areas where lowland is not possible, upland is an important food supply. It is cultivated alone or in combination with other crops. Continuous effort toward improving its productivity is needed.