Mr Zhu Kezhen is a famous scientist in China and has made great contributions in the field of climatology. He divided the periods of ancient climate change in China into archaeological periods, phenological periods and local chronicles, which is of great significance for us to understand the history and characteristics of ancient climate change in China.
Archaeological period is the first paleoclimate change period in China classified by Mr. Zhu Kezhen. This period mainly refers to the primitive society and slave society in ancient China, from about 5000 BC to about 2000 BC. During this period, the climate in China was warm and humid, which was suitable for agricultural development. Archaeologists have discovered some clues about climate change through the excavation and research of ancient sites.
For example, during the Yangshao culture period, people began to grow rice, indicating that the climatic conditions at that time were suitable for rice growth. However, during the Longshan culture period, the rice planting area decreased obviously, which may be related to climate change.
Phenological period is the second period of ancient climate change in China, which was classified by Mr. Zhu Kezhen. Phenology refers to the relationship between biological phenomena such as plant growth and development, animal migration and climate. During this period, the climate change in ancient China was mainly reflected by the change of phenology.
For example, farmers in ancient China arranged their farming activities according to phenological changes, such as sowing and harvesting. Mr. Zhu Kezhen discovered some records about phenological changes through the study of ancient documents. For example, there is a poem in the Book of Songs, "Spring rains startle spring and sting the sky", indicating that spring came earlier and the climate was warmer at that time.
In the Tang Dynasty, Du Fu wrote in "Looking at Spring" that "although the country is broken, the mountains and rivers remain forever, and the vegetation turns green in spring", indicating that spring comes later and the climate is colder.
The period of local chronicles is the third period of climate change in ancient China classified by Mr. Zhu Kezhen. Local chronicles refer to local chronicles, which is a kind of ancient geography of China. During this period, the climate change in ancient China was mainly reflected by the records of local chronicles. Mr. Zhu Kezhen discovered some clues about climate change through the study of local chronicles.
For example, the annals of Jiangnan in the Ming Dynasty recorded the climate characteristics of Jiangnan, with abundant rainfall and distinct seasons. This shows that the climate change in Jiangnan area in Ming Dynasty is similar to the present climate characteristics.