Behind this is the rise of emerging countries such as China and the elevation to the middle class of billions of people who now require a diet richer than the traditional staples of rice and wheat.

The yield and quality of rice can be improved by the balance fertilization method in middle elevation area of southwest Guizhou.

In the plane layout of double dikes, the sudden expansion or contraction should be avoided. The elevation of the top of the dike should be identical with middle tide level.