<Tr> <Th_colspan="2"> Standard Mandarin </Th> </Tr> <Tr> <Th> Hanyu Pinyin </Th> <Td> Huángtǔ Gāoyuán </Td> </Tr> <P> The Loess Plateau, also known as the Huangtu Plateau, is a 640,000 km (250,000 sq mi) plateau located around the Wei River valley and the southern half of the Ordos Loop of the Yellow River in central China . It covers almost all of the provinces of Shaanxi and Shanxi and extends into parts of Gansu, Ningxia, and Inner Mongolia . It was enormously important to Chinese history, as it formed one of the early cradle of Chinese civilization and its eroded silt is responsible for the great fertility of the North China Plain, along with the repeated and massively destructive floods of the Yellow River . Its soil has been called "most highly erodible...on earth" and conservation efforts and land management are a major focus of modern Chinese agriculture . </P> <P> The area is named for its most distinctive feature, the highly friable "loess" (German for "loose"; Chinese: 黃土, huángtǔ, "yellow earth") soil that has been deposited by wind storms over the ages . </P>

What was loess used for in ancient china
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