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Abstract

A multidisciplinary field-scale trial was established on the AGCO Corporation Future Farm (Lusaka, Zambia) in May 2014 to investigate the interaction between traffic and tillage management strategies on soil health, crop performance and system economics. The fully-randomised and replicated factorial design will determine the interaction between field traffic intensity, low ground pressure systems and controlled traffic farming with conventional, conservation and zero tillage. The aim of this study is to develop management approaches that both optimise the soil and water resource while providing excellent crop performance, competitive farm economics and reducing environmental negatives.

Description

Agricultural production in Sub Saharan Africa has previously involved high labour intensity, low levels of additions and almost no mechanisation. However, crop production has recently been developing at a fast pace with a growing trend toward increasing output using highly mechanised systems of more economically developed regions. These systems, characterised by high field traffic intensity and regular, invasive tillage, have been shown to negatively impact soil health, water use efficiency and crop performance. Reversing these negative impacts necessities further time consuming and costly tillage. In order to tackle the growing international food demand while minimising environmental damage associated with intensive production, innovative solutions have been engineered to not only mitigate these problems but to also increase crop performance and reduce costs.

Advances in precision agriculture have facilitated the development of field management approaches that reduce surface area trafficked. Controlled traffic farming, now common in Australia and the United States of America, uses precision guidance and auto steer technology to confine annual traffic to permanent wheel-ways reducing trafficked surface area from more than 80% to less than 30% (dependant on specific system). Low ground pressure technology can be an effective alternative to traffic control, reducing pressure transmission. Conservation tillage methods such as minimum and strip tillage, alongside zero tillage, have the capacity to greatly reduce the negative consequences associated with intensive tillage.

The first research period was focused on normalising the 12 ha trial site using a Radium Engineering PowerCombo sub soiler. Any remaining variation in soil type, physical structure, soil chemical properties, crop growth and yield (Soybean - Glycine max var. Semeki) was recorded and spatially mapped to provide data against which the plot trial results will be assessed. A Challenger MT865C drawing a 9.0 m Radium Engineering PowerCombo (intensive tillage) and a 9.0 m Sunflower 6333 Land Finisher (minimal tillage) will be used on cultivated plots alongside a Massey Ferguson 8690 working at high and low inflation pressures to introduce a variety of additional trafficking. Winter Wheat (Triticum aestivum var. Nduna) will be drilled to establish treatments (n=9) in May 2015 using a Sunflower 9435-30 Grain Drill. The treatments will be randomly allocated on plots (n=36) arranged in 4 blocks under a centre pivot sprinkler irrigation system. Although there is a wealth of research internationally surrounding soil and water use in intensive agriculture there is very little available for the Sub Saharan African growing climate specifically. This study will develop best practice guidelines to protect soil health while maximising crop performance and farm economics based on data from the region.

 

External Supervisor - Dr. Mark Moore AGCO Corporation