The invention discloses a kale growth substrate based on
construction waste and a preparation method thereof, and belongs to the technical field of
fertilizer synergism. On the basis of preliminarily reducing the
salinity and
alkalinity of waste concrete and waste
brick particles in the substrate,
gypsum powder, elemental
sulfur and complex
microbial inoculant bacteria are adopted to continuously acidify an alkali source in the substrate, so that the content of the alkali source in the substrate is reduced; and residual salt is locked by adopting a
nutrient slow-release film, so that the effect of rapidly and persistently reducing alkali and salt of the
construction waste particles is realized, and a slightly acidic and low-salt
root system environment is provided for the growth of the kale. According to the kale growth substrate based on the
construction waste, the pH value is maintained to be 6.2-6.7, the EC value is as low as 1.0 mS.cm <-1 >-1.4 mS.cm <-1 >, the ventilation
porosity is larger than or equal to 18%, the
water holding porosity is larger than or equal to 45%,
total nitrogen is 1.8 g.kg <-1 >-2.2 g.kg <-1 >, available
phosphorus is larger than or equal to 35 mg.kg <-1 >, and available
potassium is larger than or equal to 250 mg.kg <-1 >.