MICRONUTRIENT CONCENTRATIONS OF COMMERCIALLY GROWN VEGETABLES AND OF SOILS IN THE LOWER FRASER VALLEY OF BRITISH-COLUMBIA

Zinc (Zn), copper (Cu) and molybdenum (Mo) concentrations of potatoes, cabbage, cauliflower, carrot, turnip, corn and lettuce grown commerci ally in three important agricultural regions of the Lower Fraser Valle y of British Columbia were surveyed. Zinc and Cu concentrations in the edible portions of the various vegetables were within and frequently at the lower range of concentrations reported for corresponding vegeta bles grown in other non-contaminated areas of the world. It was conclu ded that there is more concern about low levels than about toxic Zn an d Cu concentrations for vegetables grown in the Lower Fraser Valley. M olybdenum concentrations tended to be greater than those reported else where in the world. Instances of high concentrations were quite site s pecific. At one location, the concentrations of Zn, Cu and Mo in potat o tubers were considerably higher than in potatoes at other locations but it was not possible to determine whether this was due to the culti var grown, the characteristics of the soil or management practices. Th e concentrations of the three metals in non-edible parts of the vegeta bles frequently varied more than the part normally consumed showing th at extrapolation of the survey data to other types of vegetables regar ding human nutrition quality must be made with caution. There were few correlations between concentrations of the elements in plants and in the corresponding soils, limiting extrapolation to other locations by soil analyses. A comparison of adjacent sites showed greater total soi l Cu and Mo, and extractable P and K, concentrations under cultivated than under virgin conditions.