Plant diversity and profile distribution of some available micronutrients in selected soils of Kano State, Nigeria

Abstract

Availability of micronutrients in the right amount and proportion is vital for optimum nutrients utilization by diversity of plants. However, the current fertilizer recommendation for plants in Northern Nigeria is only for macronutrients and continuous application of one or two macronutrients may deplete the soil reserve of other nutrients; micronutrients inclusive, due to nutrients antagonism and consequently, reduce plant yield. For these reasons, this study was conducted to assess the profile distribution of zinc, copper, iron and manganese in selected soils of Kano state, Nigeria. Thirteen profile pits were sunk across thirteen (13) local government areas of Kano state. A total of (39) thirty nine composite samples were collected according to the pedogenic horizons at the different locations. In addition to the determination of other physical and chemical properties, available micronutrients; Cu, Fe, Zn and Mn were extracted with 0.1N HCl and the concentration of nutrients measured with atomic absorption spectrophotometer (AAS). Data obtained were subjected to Generalized Linear Model (GLM) procedure of Statistical Analysis Software (SAS) laid down in a randomized complete block design (RCBD). Significantly different means were then separated using Duncan multiple range test. Results obtained revealed that although Fe and Mn contents were adequate for crop production, Zn and Cu values ranges from 0.79 to 1.14 mg kg^-1 and 0.76 to 1.11 mg kg^- respectively and were rated as inadequate in all the soils of the study area as such, supplementary application of these micronutrients could be beneficial for plant diversity development. Similarly, addition of organic residues as well as including Cu and Zn in fertilizer blends to be used in soils of the study area is necessary to improve plant diversity development. However, result of plant diversity is indicated with the Sahel Savanna having1,086 species, Sudan Savanna 1,116 species and 1,264 species in the Northern Guinea Savanna respectively.

Keywords: Distribution, Kano state, Micronutrients, Plant diversity, Soil profile