59 / 92
57
November 2015
CA is beneficial to soil biology, but practices such as cropping
sequence or combinations should be carefully tested to guarantee
the maximum improvement in soil biology in the shortest possible
timeframe. Indicator trends in soil biology, such as microbial diver-
sity and activity, soil CO
2
respiration and POM, should be monitored
over time to attain a more complete understanding of the impact that
different farming practices might have on soil health.
For more information, contact Hendrik Smith at
hendrik.smith@
grainsa.co.za
, Willie Pretorius at
willie@cropsystems.co.za ,Johan
Habig at
HabigJ@arc.agric.zaand Gerrie Trytsman at
gtrytsman@
arc.agric.za.
Graph 5: PMN from Solvita CO
2
respiration at Ottosdal, March 2015.
Graph 6: Organic carbon content in 5 g of soil from two different farms indicate the proportionate
amount of carbon in the particulate organic matter (POM) and bound to the mineral surfaces
(mineral bound).