Abstract:
Ecosystems in semi-arid and arid Southern Africa experience high temperatures which translate to extremely hot
soil surface temperatures. High soil surface temperatures lead to a decrease in seed germination and consequently
less plant cover in these areas. To facilitate maintenance of optimum plant cover, soil surface temperature should
be moderated with appropriate mitigation techniques. Temperature variations in low (kg.0.5 m 3) and high
density (1 kg m 3) brush packing treatments were compared to bare soil. We also measured the grass productivity
(g.m 2) against the effect of temperature in the three treatments. iButtons® were used to log soil surface temperature
every hour for seven months. Daily and nightly temperatures of the hottest months were compared
amongst the three treatments. Mid-day temperatures, corresponding to peak heat stress were also compared
between the three treatments. There was a significant difference (p < 0.01) in soil surface temperature between
the three treatments. The high density treatment was the most buffered against temperature variation, when
compared to the bare soil. Grass production was generally higher in the high density treatment. Productivity can
be increased by mulching the soil with brush packing as this will improve soil surface conditions such as
moderating abrupt changes in temperatures to assist plant growth.
