关键词: 不同土壤类型, 表层分布特征, 垂直分布, Cu和Zn

Abstract: Four typical farmland soils （alluvial soil, lime concretion black soil, yellow-cinnamon soil and cinnamon soil） were selected to analyze the distribution characteristics of Cu and Zn contents in farmland. Results showed that the Cu content in the surface of different soils was in order as followingYellow-cinnamon soil > lime concretion black soil > cinnamon soil > alluvial soil; In addition, Cu content in yellow-cinnamon soil was significantly different from that in other three soil types. The Zn content in the lime concretion black soil was as high as 225.40 mg/kg, which was significantly higher than that in the alluvial soil, yellow-cinnamon soil and cinnamon soil. According to the vertical distribution characteristics, the contents in the surface layer（0~20 cm） of Cu and Zn in the lime concretion black soil and yellow-cinnamon soil were significantly higher than that in the 20~40 cm and 40~60 cm soil layer. For the Cu content in alluvial soil, there was no significant difference between the soil layer of 0~20 cm and 40~60 cm. However, the Cu content of 0~20 cm for cinnamon soil was significantly different from that of 20~40 cm and 40~60 cm soil layers. The content of Zn in lime concretion black soil, yellow-cinnamon soil and cinnamon soil showed a trend of gradual increased with the increase of soil depth. The content of Cu and Zn in the four different soil types was lower than the national standard, which were in the stage of cleaning and still cleaning.

Key words: different soil types, distribution characteristics on the surface, vertical distribution, Cu and Zn