Preparation of a Slow Release Biofertilizer From a Polymeric Urea-Formaldehyde Matrix (PUFM)

Fertilizers industry faces the challenge of improving the efficiency of itsproducts either by optimizing the fertilizers in use or by developing new types ofthem. During the last decade, controlled and slow release technologies havebecome more important. These technologies aim to increase the efficiency of theapplied substance by increasing its action over time and avoiding losses of all kinds(leaching, volatilization). The main purpose of the current study was to obtain aslow release biofertilizer by incorporating microalgae into a polymeric ureaformaldehydematrix (PUFM). The quantitative analysis of macronutrients andmicronutrients in the microalgae was determined using different techniquesincluding titration, UV and Atomic Adsorption Spectroscopy. The matrix and theformulation obtained (PUFM + CHLO) were also characterized by InfraredSpectroscopy (FTIR) and Scanning Electron Microscopy (SEM). The “in vitro”study showed a typical slow release behavior of nitrogen (N), phosphorus (P) andpotassium (K) macronutrients. It was also shown that (PUFM+CHLO) formulationhas the slowest macronutrients release time with a maximum release of 28%, 26%y 46% for (N-P-K) macronutrients respectively during a period of 30 days. The "invivo" study exposed the benefits of the biofertilizer formulation (PUFM + CHLO)from conventional commercial fertilizer (CF) (NPK-14-5-12). Due to the presenceof nutrients of natural origin in microalgae, (PUFM + CHLO) shows ecologicaleffects which could also developing sustainable agriculture systems.