Mineral composition of soil and pasture from areas of grazed paddocks, affected and unaffected by dung and urine

Open Access
Publisher Website
Google Scholar
Abstract
Plant and soil samples were collected from areas presumed to be affected and unaffected by dung and urine. The samples were taken in September and November, at least 21 days after grazing. The affected pasture was distinguished from the unaffected pasture by its greater height and deeper green colour. On analysis, the affected pasture had a higher content of grasses, higher concentrations of potassium (K), phosphorus (P), and molybdenum (Mo) in the herbage, but lower concentrations of calcium (Ca), copper (Cu), and selenium (Se). There were no significant differences in nitrogen (N), magnesium (Mg), or sulphur (S). The levels of available P, S, K, Ca, and Mg m the soil under the affected pasture were higher, and sodium (Na) was slightly lower than in the soil under the surrounding pasture. Where grazing pressure was high, 70–80% of the pasture available to stock was affected pasture. With this high proportion of the total pasture produced on soil of high nutrient status field experiments on grazed pastures may show very little response to fertiliser, despite low mineral levels in soil or plant samples taken from the depleted, unaffected areas. It also follows that, as grazing pressure increases,. more pasture Will be influenced by dung and unne, and stock will eat an increasing amount of pasture which has higher K : (Ca + Mg) and K: Na ratios, lower Ca : P and Cu : Mo ratios, and lower Se content. This may increase the incidence of mineral-related animal health problems.

This publication has 16 references indexed in Scilit: