First of all, the Huaihe River is the dividing line between the north and the south of China. In the climate division of China, the south of Huaihe River is subtropical and the north is warm temperate zone. Huaihe river basin is located in the transition zone between rainy areas in the south of the Yangtze River and rainy areas in North China, with a great annual rainfall gradient. The rainy season and dry season in the north and south of Huaihe River are just the opposite.

South of Huaihe River, the rainy season is long and the rainfall is heavy, which is suitable for planting rice with large water demand. There is little rain and drought in spring to the north of Huaihe River, so drought-tolerant winter wheat should be planted. Therefore, a big pattern of grain production layout in China has been formed in history. As a result, southerners love rice and northerners love pasta.

Secondly, due to the different climate, topography and land and sea location in the north and south, two different styles of eating habits have been formed. There is less rainfall, arid climate and more dry land in the north, which is suitable for planting wheat. Therefore, when the wheat yield is high, more people eat. Wheat is suitable for the arid environment in the north, and people eat wheat to adapt to the climate in the north. Traditionally, they mainly eat pasta.

South China is suitable for planting rice because of its heavy rainfall, humid climate and many paddy fields. Therefore, the output of rice is large, and more people eat rice. Rice is suitable for the humid environment in the south, and people eat rice to adapt to the humid climate in the south. Traditionally, they mainly eat rice. The dietary habits formed by the differences between North and South just add color to China cuisine.

The north is mainly located in the middle temperate zone and warm temperate zone, with less precipitation and lower temperature. The cultivated land is mostly dry land, which is suitable for planting drought-tolerant and cold-resistant wheat, corn, millet and sorghum. The pasta that Fang people like to eat is made of flour ground from wheat.

The southern region is mainly located in the subtropical zone and tropical zone, and the climate is hot and rainy, with paddy fields as the main cultivated land, and rice is a crop with high requirements for heat and moisture, so farmers in the south often plant rice with high temperature and rainy growth habits according to local conditions. The staple food rice and rice noodles that southerners like to eat are processed rice.