Research NoteOrganic matter content of a soil in a semi-arid climate with three long-standing veld conditions

Abstract

The effect of maintaining veld in three conditions, viz. poor, moderate and good, for 15 years, on the organic carbon (C) and total nitrogen (N) content (as measures of organic matter content) of a fine sandy loam soil was investigated. Composite soil samples were collected and analysed to a depth of 300 mm at 50mm depth intervals from plots with the imposed veld conditions. The organic C and total N content of the soil under the three veld conditions differed significantly (P < 0.05). Both variables declined as the veld condition degraded. Total N differed less than organic C. The largest differences were measured in the 0-50 mm layer and the smallest in the 250-300mm layer. Losses of soil organic matter can be attributed to reduced phytomass production, increased soil erosion and change in soil climate. It is suggested that the loss of soil organic matter from degraded veld may inhibit veld recovery.

Keywords: carbon; condition; erosion; nitrogen; organic carbon; organic matter; phytomass; phytomass production; soil erosion; soil organic matter; soil samples; south africa; veld condition

African Journal of Range & Forage Science, 10(2): pp. 108-110