Abstract: Six major types of land use (deserted farmland, bare land, shrub land, grassland, Pinus massoniana forest, and artificially restored forest) in the low hill region of Caohu Basin were chosen as subjects in a study to explore for characteristics of soil nutrient loss with soil interflow as affected by the land use in the region. Stationary observation and sampling of soil interflows for analysis were conducted. Results show that among the six types of land use, shrub land and grassland were the highest in probability of interflow occurrence, while bare tailing land was the lowest and had interflows only in the top 20 cm soil layer. For the nitrogen concentration in soil interflow, it was found the highest in bare tailing land and the lowest in artificially restored forest. However, phosphorus content in interflow was the highest in deserted farmland and the lowest in bare tailing land; Specifically, the nitrogen in soil interflow was found mainly in the form of dissolved NO₃^--N, of which the concentration displayed a decreasing trend with the arrival of the rainy season, but a falling and then rising trend with soil depth. The phosphorus lost with soil interflow was mainly in the form of dissolved organic phosphorus, of which the concentration displayed a decreasing trend with soil depth. Correlation analysis showed the that both nitrogen and phosphorus concentrations in soil interflow were significantly related with total land coverage, vegetation evenness and soil nutrient level, but insignificantly with amount and intensity of rainfall. Owing to the flourishing mining industry in the region, it is important to take into account the effect of dry and wet depositions when analysis is done of N content in soil interflow in the region.

Key words: Chaohu, interflow, nutrient loss, land uses