Plinthization -A threat to agricultural production

Abstract

The problem of land degradation resulting in insufficient food production for the ever-increasing population is recognized worldwide and some observations by scientists, administrators, and politicians on its threat to human existence, have been made and highlighted at scientific meetings, in newspapers, and other fora. The causes of land degradation are many and most of them are known and are being tackled for solutions. However, several of them have not received much attention but are grave. Plinthite and its hardened form, petroplinthite (ironpan), constitute the major forms of danger to land use. They are the results of unnoticed and gradual pedogenetic processes going on mostly in tropical soils. Scientists have worked for some time on the hardened form, petroplinthite, but the soft form, plinthite, has not received much attention. Over a third of the agricultural soils of Ghana have plinthic material and FAO reported that 96 920 km2 of land have already hardened and made the soil unproductive. The situation may be similar for other countries in the tropics. This paper attempts to review plinthite, its physical, chemical, mineralogical and micromorphological forms, and its importance for construction and agriculture. It also warns mankind about the danger ahead if solutions are not found for the prevention of its formation and subsequent hardening to form petroplinthite.



Ghana Jnl agric Sci. Vol.32(2) 1999: 223