Some effects on soil properties, herbage composition, and blood chemistry of sheep, arising from the irrigation of pastures with woolscour effluent

Abstract

Disposal of woolscouring wastes by land irrigation of a Waimakariri very stony sandy loam soil caused significant increases in pH, base saturation, and exchangeable potassium, and significant decreases in exchangeable sodium and magnesium in the soil. Chemical analysis of pastures, treated with effluent for up to 6 years, showed very high K, significantly lower calcium, higher copper and lower manganese concentrations when compared with untreated ryegrass. Mean sera analyses for Ca, Mg, Na, and K on blood from sheep grazing the effluent-treated pastures were not significantly different from figures found for stock fed on untreated pastures on the same soil type. It is concluded that land irrigation of this freely draining soil type affords a satisfactory means of disposing of woolscour wastes, but if it is continued indefinitely, soil pH and pasture chemical composition should be monitored to indicate if further changes likely to adversely affect pasture production or stock health are occurring.

Keywords:

• Effluent disposal
• woolscour effluent
• soil
• pasture
• stock health