Agrochemical assessment of the effect of vermiculite on reducing ammonium ion mobility

An agrochemical assessment of the effect of expanded vermiculite on reducing ammonium ions mobility was carried out using methods of phytotesting soil mixtures with determination of nitrogen forms. The studies were conducted using urea, which was added in granular or dissolved form in a wide range of nitrogen dose values, including those exceeding the maximum permissible concentration. We used two types of soil, which differ in the content of the organic component. It has been shown that expanded vermiculite effectively reduces the content of the exchangeable form of ammonium; fixed ammonium turns into the nitrate form more slowly compared to exchangeable ammonium.