Investigation of exploitation of iron placer deposit effects on physicochemical properties of agricultural dryland soils, Baklik Basin, Markazi Province, Iran

Abstract

Consumption rate of mineral resources continuously increases with industrialization and urbanization, as well as with population growth. Previous explorations of iron (Fe) placer deposits in the Baklik Basin of Markazi Province in Iran showed that a high level of Fe placer deposits exist in the region that may be considered a valuable mining deposit. To investigate effects of Fe placer deposits' exploitation on physicochemical characteristics of dryland soils, the topsoil (0 to 30 cm [0 to 11.8 in]) was cut and moved to one corner of the pilot site (2 ha [4.9 ac]) by bucket loader. A magnetic separation device was used to separate magnetite substances from the soil. After magnetite separation, the treated soil was returned to the site and leveled, then deeply plowed to mix with the underlying soil. Contour plowing or plowing across slope and along elevation line were carried out to mitigate soil erosion. Analysis of physicochemical characteristics of several soil samples and study of soil, water, and plant interactions in experimental plots show that there are no significant differences between treated and untreated soils. However, it is necessary to carry out soil conservation practices in the treated parcels to avoid wind and water erosions during dry and wet seasons.