Soil Compaction, Organic Matter, and Phosphorus Addition Effects on Growth and Phosphorus Accumulation of Clover

Abstract

Compaction of soils is known to reduce crop yield. The impacts on crop yield may be imparted through effects on plant nutrition. Thus, interactive effects of different levels of soil compaction (bulk densities of 1.4, 1.65, and 1.8 Mg m−3), organic matter (0, 20, and 40 Mg ha−1), and phosphorus (P) (0, 25, and 50 mg kg−1 P) on growth and P accumulation of Berseem or Egyptian clover (Trifolium alexandrimum L.) were investigated in a factorial experiment with a randomized block design. Results indicated that as soil compaction increased, the dry mass of shoots and roots, root length, and P accumulation in shoots and roots decreased. Application of organic matter reduced soil compactability. Organic matter and P additions significantly increased the dry mass of shoots and roots, root length, P accumulation in roots and shoots, and total P accumulation by clover. The highest dry mass of shoots and P accumulation by the crop were obtained with the lowest soil compaction level that received 50 mg kg−1 P and 40 Mg ha−1 of organic matter. The adverse effect of soil compaction on P accumulation was reduced by the addition of organic matter.