Biological eutrophic seedling substrate and preparation method thereof

The invention belongs to the technical field of seedling raising substrates, and particularly relates to a biological eutrophic seedling raising substrate and a preparation method thereof.The biological eutrophic seedling raising substrate is prepared from, by weight, 40-60 parts of fermented organic matter, 15-25 parts of modified biomass charcoal, 0.5-0.8 part of microbial agent, 20-30 parts of urea, 10-12 parts of ammonium nitrate, 8-12 parts of monopotassium phosphate and 3-5 parts of vermiculite. Wherein the fermented organic matter is prepared by the following steps: S1, crushing agricultural wastes and livestock and poultry manure in a mass ratio of 2: 1, which are free of chemical residues and diseases and insect pests, by using a crusher, so as to obtain a pretreated organic matter; s2, the pretreated organic matter is evenly laid on a fermentation bed of a fermentation workshop, and the fermented organic matter is obtained. Through the synergistic effect of all the components in the matrix, the adap