Ion exchange resins can be used to measure the relative amount of nutrient ions available to plants and the rate at which they are removed from organic soil substances. Typical ion exchangers are ion exchange resins (functionalized porous or gel-like polymer), zeolites, montmorillonite, clay and soil humus. They are either negatively charged substitutes that take positively charged ions (cations), or anion substitutes that take negatively charged ions (anions). There are also amphoteric substituents that can simultaneously replace cations and anions. Ion-exchange resins are widely used to assess the presence of nitrogen in the soil and its spatial distribution. Anion exchange membranes absorb nitrate ions (No3−), and cation exchange membranes absorb ammonium ions (NH4+). In this article, the direct placement of strips of ion exchange resins in the soil was a simple and effective way to estimate the relative rate of release of ammonium and nitrates due to the mineralization of different soils.