2. Generally speaking, before and after beginning of winter, precipitation was less in most areas, the land in the north began to freeze, and agricultural and forestry crops entered the wintering period.
3. After winter, the air generally becomes dry and the soil water content decreases. At this time, China began to pay attention to the fire prevention work in forest areas. "Stand and build" means that winter begins from now on. But in climatology, "beginning of winter" is not fixed as beginning of winter, but uses the temperature to divide the seasons.