Long summer means the beginning of summer. Astronomically, long summer bid farewell to spring, which is the beginning of summer.
Chang Xia said that saying goodbye to spring is the beginning of summer. Spring comes and summer grows, autumn harvests and winter storage, and in the long summer, everything is thriving. Because China has a vast territory and a large span from north to south, natural rhythms vary from place to place. In the long summer season, only the area south of Fuzhou-Nanling line in China is the real summer of "the trees are dark and the summer is long, and the balcony reflects into the pond"; And some areas in the northeast and northwest have just entered spring. According to the classification standard of modern climatology (climate average temperature), summer begins when the average temperature of the day rises steadily above 22℃.
After the long summer officially entered the rainy season, rainfall and rainy days increased significantly. Spring, long summer, autumn harvest and winter storage are the best seasons for many crops to grow vigorously. Adequate light, suitable temperature and abundant rain provide necessary conditions for plants. Monsoon climate is the main feature of China climate. Summer is affected by the warm and humid air flow from the ocean, which is hot, humid and rainy, which is beneficial to crop growth. In summer, crops have entered a vigorous growth period.
After the long summer, the temperature in North China and Northwest China rose rapidly, but the precipitation was still not much. In addition, it is windy in spring with strong evaporation. Atmospheric dryness and soil drought often seriously affect the normal growth of crops.
The meaning of long summer is recorded in ancient books:
Twenty-four solar terms: Long Summer and April Festival. Make a word to understand spring. Summer, holidays. At this time, everything is fake and big. "
Tickle. Bug, bug, make a hole in the soil, go out good night, today people call it a local dog; Moles, moles and crickets have different dialects. Huai Nan Zi said, "The sound of cricket, the sound of cricket, the appearance of cricket, the beginning of Yin Qi, are two things." Summer: March is also a song. And there are five abilities, none of which are skills: flying over the house; The edge can't be bad; Can't swim across the valley; Acupoints cannot cover the body; You cannot continue. Therefore, Shuowen called Fei a five-skill mouse. Notes on Ancient and Modern Times is also called Gugu. "Yaya and Materia Medica are considered as bugs, while Lu Deming and Zheng Kangcheng think frogs are not.
The earthworm came out. Earthworms, that is, lumbricus, are also famous for their singing. In "Li Jie", it is said that those who bow to yin see through yang.
Wang Guasheng, as mentioned in the Illustration, can be seen everywhere, with wild ones, fields and walls, leaves like Trichosanthes kirilowii and Linderae, round hairs like thorns, creeping, May yellow flowers, seeds like flowers, green ripe, roots like kudzu, thin and complex, also known as Tugua, a crow melon, today. In The Book of Rites, Jacky pointed out: This is the curse. Materia Medica is China's cymbal book, and Tao lived in seclusion to distinguish its fallacies. He said that China cymbals have their own articles, but Wang Gua also has his own articles. It was ridiculous for Confucian scholars at that time to talk without consulting books.
"Yi Zhou Shu Shi Xun Jie" says: "On a long summer day, it sounds like a song. On the fifth day, the earthworm came out. Another five days, Wang Guasheng. " That is to say, in this solar term, you can first hear the chirping of grubs (that is, slugs) in the field (that is, frogs), and then you can see earthworms digging in the soil, and then the vines of melons begin to climb and grow rapidly, which describes the phenological scene at the beginning of summer dreams.
The Ming Dynasty wrote in "Eight Notes on Respect for Life": "On the day of summer dreams, heaven and earth will begin to meet, and everything is beautiful." At this time, the summer harvest crops entered the late growth stage, the winter wheat blossomed and filled, the rape was close to maturity, and the summer harvest crops were basically a foregone conclusion that year. Therefore, there is a saying in agricultural proverbs that "see summer in the long summer". Rice planting and management of other spring-sown crops have also entered a busy season. Therefore, China has always attached great importance to the long summer solar terms. According to records, during the Zhou Dynasty, on the day of long summer, the emperor personally led hundreds of civil and military officials to the suburbs to "welcome summer" and instructed Si Tuleideng and other officials to encourage farmers to work hard.