What does phenology mean?

The relationship between biological periodicity (such as germination, flowering and fruiting of plants, migration of migratory birds and hibernation of some animals) and seasonal climate. It also refers to the relationship between abiotic changes in nature (such as first frost and thawing). ) and seasonal climate.

Seventy-two phenology is based on the observation of natural phenomena such as birds, animals, grasses, trees and the changes of cold and warm weather in the ancient Yellow River basin in China. It is summarized in five days to express the regularity of meteorological cycle, which is a detailed explanation and enrichment of the twenty-four solar terms.

Ancient climate

The ancient ancestors took five days as the waiting period, three times as qi, six times as time, and four times as age, with 24 solar terms and 72 waiting periods every year. The word "climate" is a generalization of solar terms and climate. As early as more than two thousand years ago, Yizhoushu was the sixth Juan? Time training solution? There is a complete record of the use of solar terms and climate in volume 52.

The phenology calculated by the ancients is 72 days a year, and every 5 days is 360 days, but there are 365 days a year. Therefore, it is stipulated that the 26th to the end of each month, the sixth day of the Gregorian calendar, and the first day of this month is six days if it meets the 3rd1of the big month.