JAMB Agricultural Science 2021 Paper

Concept:Soil fertility is the ability of the soil to supply all essential plant nutrients in the right amounts and balance.Explanation:A fertile soil contains major nutrients such as nitrogen ($\mathrm{N}$), phosphorus ($\mathrm{P}$), and potassium ($\mathrm{K}$) in sufficient quantity.It must also contain secondary and micronutrients like calcium ($\mathrm{Ca}$), magnesium ($\mathrm{Mg}$), sulfur ($\mathrm{S}$), and iron ($\mathrm{Fe}$).These nutrients must be present in suitable proportions to support normal plant growth and development.Good drainage and aeration are good physical conditions, but they do not define fertility on their own.The ability to produce a good cowpea harvest is only an outcome of fertile soil, not the correct definition.Answer:D. Fertile soil is one which contains all essential plant nutrients in suitable proportion.