For the 0-40cm sandy-clay-loam the comparison across PAWC magnitudes showed no difference in yields in the low and medium rainfall zone. For the high rainfall zone, comparison showed moderate yield differences. For the 0-60cm sand, comparison between the 20-40mm and 40-70mm showed low statistical yield differences while comparisons between 70-100mm PAWC were statistically significant in the low rainfall zone. For the medium and high rainfall zone, yield differences were in the high to very high categories for the majority of comparisons. For the 0-60cm sandy-loam, comparison of yield differences across PAWC values in the low rainfall zone shows low significance between in the 20-40mm and 40-70mm PAWC as well as the 70-100mm and 100+mm PAWC categories. Comparisons across these categories showed very high significance. In the medium rainfall zone, low yield differences were found between the 70-100mm and 100+mm PAWC categories while other cross comparisons generated very high statistically significant yield differences. For high rainfall zones, high significant differences existed between simulated yields for the 20-40mm and 40-70mm PAWC soil characterisations. Less significant differences were found for the 70-100mm and 100+mm PAWC soils while other cross comparisons showed very high number of regions had statistically significant yield differences. For the 0-60cm rooting depth sandy-clay-loam comparisons across the all rainfall regions showed the majority of regions showed very high significant yield differences. The exception was in the high rainfall region where a high rate was recorded in the 70-100mm and 100+mm PAWC comparison. For the 0-60cm rooting depth, clay loam soil category showed very high significant yield differences in the low, medium and high rainfall zones. For the 0-100cm root zone and sand texture type showed moderate to high yield differences were found between the 20-40cm and 40-70cm PAWC categories in the low rainfall zones. The yield significance for these categories was moderate in the medium and high rainfall zones. Cross comparisons between the 20-40mm and 4070mm PAWC values with the 70-100mm and 100+mm PAWC showed very high significance in yield differences. Comparison between the 70-100mm and 100+mm PAWC categories showed low yield significance in the low and medium rainfall zones with low to moderate significance in the high rainfall zone. For the 0-60cm loamy-sand, changes in PAWC showed significant yield in the 4070mm PAWC in the low and medium rainfall zones. No difference were found between the 70-100mm and 100mm +PAWC levels in the low rainfall zone while only moderate yield differences were shown in the medium rainfall zone. All PAWC comparisons showed very high yield differences in the high rainfall zones. For the 0-100cm root zone sandy-loam category changes in PAWC showed very high significant yield differences across all PAWC levels in the low, medium and high rainfall zones.
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