Trends of the content of selected mineral elements in waters for fertigation of vegetable grown under covers

The aim of the study was the monitoring the mineral composition of the water used for fertigation in soilless culture. The study was conducted in the years 2010-2012 and analyzed a total of 360 samples of water from different water intakes of the major areas of vegetable production in greenhouses. The water samples were determined pH, conductivity (EC), the content of minerals and ballast ions. In each sample of water collected, the contents of bicarbonates were determined. During two years of research, an increase in the average content of bicarbonates average 80 mg.dm-3 and pH by 0.17 units on average. The content of total dissolved salts in the course of the observation period decreased. The average value of EC decreased by 0.14 mS.cm-1. The nitrate content according to the water intakes varied over a wide range from 0.05 to 128 mg.dm-3. During follow-up, two-year downward trend ballast ion content such as Cl-and SO42-, and sodium (Na +), there was no change and remained at an average level of 21.0 mg.dm-3. ...