摘要 |
Nitrogen compounds are a source of soil acidity. In addition nitrates are a major factor in the leaching of other nutrient salts from soils. These salts are then replaced by the available hydrogen ions, rendering the soil even more acidic. Besides supplying nutrients, a desirable fertilizer should offset changes in soil acidity brought about by nitrification. Calcium carbonate accomplishes this. Unfortunately it has not been possible commercially to include calcium carbonate in a fertilizer. If CaCO3 particles are ground too large they do not dissolve along with the agricultural fertilizer nutrients. If CaO3 is pulverized to a state necessary for dissolution, because of its hygroscopic properties, it hardens or cakes. It is not sufficiently stable in admixture with the other fertilizer materials for commercial distribution. Herein a fertilizer is provided which improves the condition of the soil, and stimulates microbial activity in the soil. It also has a shelf life rendering it marketable commercially. Rather than forming agglomerates or pellets in the form of a binder-CaCO3 matrix as has been the practice heretofore, only the outer layer of the pellets herein are in matrix form.
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