DAT Ecology Practice Exam 2026 – Your All-in-One Guide to Mastering Ecology!

During decomposition, microbes break down nitrogen-containing organic matter (like proteins and amino acids) into ammonium (NH4+). This step is called ammonification. It returns nitrogen to an inorganic form that plants can use, or that can be further processed by other microbes (for example, by nitrification turning NH4+ into nitrite and nitrate). Nitrification, denitrification, and nitrogen fixation are other parts of the cycle, but they don’t involve releasing nitrogen from organic matter as ammonium.