Roger Tremblay1 and Charles Karemangingo2
Partner: New Brunswick Cranberry Growers Association
Abstract: The irrigation water quality can be a key issue for the cranberry industry since high salt contents in water can increase soil salinity and so reduce plant growth and production potential. This project monitored the cranberry irrigation water quality of 18 farms across the province. The project had also to test and validate the YSI kit for water electrical conductivity (EC) and pH measurements in fields as a tool that individual cranberry farmers can use. Water samples were collected from different sections of the irrigation system including rivers, ponds, flooding and drainage ditches. The ponds were water sampled from the top (± 30 cm), 1 m water depth, and the bottom. A total of 103 water samples were collected and tested for EC, pH, and dissolved nutrient concentrations. EC and pH were also field-measured using the YSI kit. The results indicated that the physicochemical properties of irrigation water were still suitable for cranberry production. The EC varied from 30.0 microsecond cm-1 to 420.0 microsecond cm-1 with the third percentile value of 130.0 microsecond cm-1. In general, the water EC increased from the rivers to the flooding ditches and then decreased in the drainage ditches. Such a decrease means that a certain amount of salts may be accumulating in cranberry soils. The YSI test kit can be used to monitor the water salt content using the following regression equation: EC lab ( microsecond cm-1) = 1.0833 x (EC YSI) microsecond cm-1 + 14.399 microsecond cm-1 (R2 = 0.94). In 2004, particular attention is being paid towards a few farmers whose irrigation water EC was close to or above 400.00 microsecond cm-1, which is the maximum acceptable EC level for the production of most crops.
1 NB Department of Agriculture, Fisheries and Aquaculture, Agriculture Development Branch, PO Box 6000, Fredericton, NB, E3B 5H1
2 NB Department of Agriculture, Fisheries and Aquaculture, Land Development Branch, PO Box 6000, Fredericton, NB E3B 5H1