Efficient nutrient use is key to reducing nutrient runoff
Healthy soil and good water management are vital to reducing nutrient runoff from agriculture. However, at the core of the issue are the nutrients added to fields, mainly phosphorus and nitrogen. These serve a vital purpose when it comes to delivering the nutrients crops need to grow – but what is not taken up by the growing crops or stored in the soil risks travelling beyond the field and contributing to eutrophication.
Adding to the challenge is that large amounts of nutrients are brought into the food system, and transformed into manure – by directly through importing animal feed or by fertilizing crops for animals with mineral fertilizers. At the same time the nutrients in resulting manure are not efficiently used in crop production as farms have become larger and more specialized. In an efficient system nutrients circulate in the system and the risk of runoff is small.
In addition to systematic change to a more circular food system, the decisions on the farm level remain important. What amount of nutrients is needed, and how should it be applied to ensure efficient uptake and avoid over-fertilization? The answer is unique for each field and depends on several factors including soil type, soil nutrient status and the composition of the soil, in addition to what kind of crops are being grown and even the weather conditions.
Keeping track of nutrient use and taking action to be more efficient is the key to successful nutrient management on any farm, benefiting both the farmer and nature.