When you buy fertilizer, you'll notice three numbers on the label, for instance, 12, 6, 6. These indicate the percentage of three key nutrients: nitrogen, phosphorus, and potassium. For green grass, nitrogen is the most important ingredient.
How is the fish on your dinner plate tied to agricultural fertilizer? Let’s use the ecosystem approach to think about the big picture. On land, nitrogen-rich fertilizer is applied to crops to stimulate production.