In many discussions with land managers, we find in discussion a distinct assessment of water quality being taken for granted. Water quality is an important measure when looking at mixing tank chemical and fertiliser blends or even regular irrigation events.
The source and seasonality are important when looking at water quality and fluctuations can occur over a season. In one example on the River Murray, over the course of an irrigation season, the pH of the water can range from pH 7 all the way up to pH 10.
Remembering also that the pH scale is logarithmic, meaning that every pH unit increase or decrease is a ten fold increase. This means that when you increase the pH by 10 units you are 1000 times more alkaline than when you started. Along with these changes on pH there can be vast changes in Electrical Conductivity ( Salt Content) and overall nutrient concentration.
These influences can have marked effect on chemical efficacy and fertiliser efficiency across all management systems.