BENEFITS OF BIOSOLIDS TO SOIL QUALITY AND FERTILITY

Abstract

ABSTRACT Research in the UK on the beneficial aspects of biosolids additions to land has primarily concentrated on nitrogen and phosphorus supply. Biosolids have other beneficial effects on soil through the addition of organic matter and other plant nutrients such as sulphur, magnesium and sodium. This study evaluates the effects of biosolids additions on soil quality and fertility at seven established field experimental sites where biosolids have been applied for at least four years. These additions influenced several physical properties of the soil, increasing topsoil water‐infiltration rates, plant‐available water supply on a light sandy soil, soil porosity and bearing strength. There were also increases in the level of plant‐available sulphur, magnesium, copper and boron. Liquid digested biosolids applications also increased the concentrations of major nutrients in grass.