Add just enough fertilizer, and crops thrive. Add too much, and you may end up with contaminated surface and groundwater.
Excess nutrients from farms can be transported to groundwater reservoirs by water starting at the surface and flowing through soil. But the flow of water through soil is a “highly dynamic process” It can vary from year to year, season to season, or even rainstorm to rainstorm.”
It can also fluctuate depending on soil type and even if organic additions, like manure, are applied.
A lead author of a new study that shows water infiltrates deeper into cracking clay (vertisolic soils) when liquid fertilisers are used and can lead to contamination of ground water and ruin diverse ecosystems.
“This observation challenges the previous studies, which showed that cracks in clay type soils called Vertisols. Can lead to the promotion of fertiliser deep into the soil and underground water systems ” he said.
But knowledge gaps remain about soil water flow in Vertisols, especially with organic additions.
But it is food for thought and prompts the question should we encourage mandatory soil core testing during the process of adding fertiliser. What do you Think.