Abstract: The irrigated areas along the Yellow River are very important in economic development in Gansu Province. Saline or alkaline wasteland, secondary soil salinization and irrational utilization of water resources are the main factors to restrict the agricultural development. In this paper, the general situation of soil salinization in the irrigated areas along the Yellow River in Gansu Province was expounded. Available data were used to analyze the characteristics of soil salt content, ionic composition and distribution as well as soil pH value and groundwater salinity. The climate, topography, soil parent material and human factors related to the formation of saline or alkaline land were also analyzed. On which some suggestions were put forward for improving soil: ① Partition improvement of saline or alkaline land should be implemented, and the prevention of secondary soil salinization must be paid great attention to; ② Utilization of water and soil resources should be optimized so as to regulate the agricultural industry structure; ③ The efficient utilization of saline or alkaline land in agricultural development should be focused on, and the biological control measures should be strengthened; ④ It is suggested to enhance the utilization of water resources so as to develop the watersaving farming system; ⑤ The dynamic monitoring of water and salt transference should be strengthened so as to develop an earlywarning system of soil salinization.

Key words: font-size: 10.5pt, mso-bidi-font-family: 宋体, mso-font-kerning: 1.0pt, mso-ansi-language: EN-US, mso-fareast-language: ZH-CN, saline or alkaline land')">mso-bidi-language: AR-SA" lang="EN-US">saline or alkaline land, soil salinization, soil improvement, irrigated area the Yellow River, Gansu Province