Epsilon Archive for Student Projects

Abstract

The purpose of this essay is to find out if liming with Ca(OH2) and CaO can reduce leaching
of phosphorus from agricultural land and the problem with eutrophication. This purpose also
includes getting knowledge about how to make the phosphorus retained in the soil and be
accessible for the plants. This essay is supposed to show if more research is needed in this
subject. There has not been much research about this subject and therefore the amount of
material to study is limited in this literature review. The research reports that have been
studied have similar results. Liming does improve the soil structure and make the phosphorus
more accessible to the plants as the phosphorus binds to calcium ions instead of iron or
aluminum. Improvement of soil structure reduces the leakage as phosphorus bound to
particles remain inside the soil. Also lime mixed in sludge does give these effects. More
research is needed about the long time effects from liming. Today it is known that the
structure improvement does remain for more than ten years but the permanency of the
chemical changes is not known. The soil type and clay content does affect the structural and
chemical properties in a soil and therefore more field experiments are needed to include
effects of liming in varying soil types. More research is also needed to get an overall picture
with both drainage water and surface runoff. The conclusion still is that liming can reduce
phosphorus losses.