The invention discloses a preparation method of a biological carbon
fertilizer. The preparation method comprises the following steps of 1, using biological carbon,
nitric acid and
ammonia water to prepare a
reaction product A; 2, fully stirring and uniformly mixing the
reaction product A, a
phosphate fertilizer,
azotobacter,
plant vinegar liquid, waste molasses and a
fertilizer additive; 3, granulating; 4, uniformly mixing
humic acid powder,
bentonite,
calcium oxide and diatomite, so as to obtain a material B; 5,
coating by a slow-release
coating material, so as to obtain a particle B; 6, using the material B to perform fertilizer
coating on the particle B, so as to obtain a particle C; 7, further
drying the prepared particle C. The preparation method has the beneficial effects that before
crop is planted, the fertilizer is applied onto the
soil surface, the fertilizer with ploughing type fertilizer
surface layer acts onto the soil, the surface fertilizer contains the
humic acid, and the inner layer is a coated biological carbon-based slow-release fertilizer; the fertilizer is reasonably applied, the
fertility of the soil is improved, and the heavy
metal and other pollutants are effectively prevented from entering the
food chain.