MINERAL-CONTENT OF THE NATURAL RANGE IN T HE SOUTHERN BRAZIL .2. SODIUM, ZINC, COPPER, IRON, AND MANGANESE

Thirty three soil samples and 275 samples of native pastures were coll ected from eleven different soil classes in Rio Grande do Sul, Brazil, in different year seasons, to determine the levels of different miner als and compare them to beef cattle requirements. Soil levers of Na ra nged from 20 to 130 ppm, with 66.4 ppm on average, and Mn levels range d from 14 to 669 ppm with 183 on average. In the pastures, the levels of Na ranged from zero to 924 ppm, with average of 269 ppm in the dry matter (DM), while those of Mn ranged from 189 to 605 ppm with average of 364 ppm. The S values ranged from 0.07 to 0.48% with an average of 0.17% in DM, while those of Zn varied from 11 to 30 ppm with an avera ge of 20 ppm. Fe levels varied from 53 to 1338 ppm with an average of 319 ppm. The average of Cu was 11 ppm, ranging from 5 to 16 ppm. The l evels of Na and Zn were deficient for cattle in all seasons in most of the soil types, while Cu was only deficient in Summer.