VFRC Publications | Page 13

Fertilizer Use Within Sustainable Planetary Boundaries Foliar application Phyllosphere bacteria Infusion of nutrients Chemical fertilizer formulation (nutrient composition/shape/size) Microbial–based interventions Endophytes Free-living soil bacteria Fungi (mycorrhizae) Biological nitrogen fixation Seed coating with nutrients Fertilizers are a fundamental human intervention in biology and all other subjects involving life on earth. Water for irrigating crops is, for example, obtained from surface and groundwater sources, helps to cool plants through transpiration to vapor back into the atmosphere and rain onto the earth surface without changing its chemical composition, and hence it cycles in the biosphere. Conversely, N2 present in the atmosphere and ore containing P, K or micronutrients deep down in the lithosphere are lifeless and inert to biology. They affect biology only when mined and processed into reactive nutrients and