Geography affects culture through topographical features such as mountains or deserts as well as climate, which can dictate options for clothing, shelter and food. The interaction of culture and geography is called human geography, which is the study of people's language, religion, medicine, economics and entertainment and how these practices have been influenced by their location.
Climate and geography play major roles in determining many lifestyle factors. One reason for China's variety of languages and customs is the variety of the terrain and climate. The North China Plain has a great deal of standing water that nourishes reeds which are used for thatched housing and woven baskets. Fish in the ponds and reservoirs are an important source of food. People live in dispersed agricultural communities and value self-sufficiency.
In contrast, life in the Yangzi Valley centers around the river and lakes. The valley has historically been an important producer of food, and the river facilitated trading. Many Yangzi residents live on boats. Manchuria is a cold, rocky region that became a mining center. Rural people live in cliff dwellings. There is a Russian influence in the towns. Contemporary Chinese feel united as a culture despite regional disparities, partly because of the influence of the media.