Increased size of farm machinery has improved farm efficiency but at the risk of soil compaction. Here we present a novel approach investigating the effect of compaction due to in-field traffic by continuously monitoring crop canopy temperature and soil profile moisture and measuring crop yield in individual crop rows to determine the economic impact on cotton farming systems. Traffic by a tractor weighing 19.2 Mg either side of the plant row reduced lint yield by 27 % due to lower crop height, leaf area, biomass and fruit number. Elevated canopy temperature (Tc) in the compacted plots resulted in 30 % higher stress time (i.e. cumulative time when Tc is higher than the optimum Tc for cotton growth) compared with the non-compacted plots. Higher stress time in compacted plots was correlated with a 72 % and 27 % reduction in crop water use (estimated from change in soil water) at 0.3−0.5 m and 0.5 – 0.7 m depths, respectively. Water recharge in the soil profile from irrigation and rainfall was reduced by 16 % due to compaction with the highest reduction being 86 % at 0.3 – 0.5 m depth. These results demonstrate that compaction likely reduced root access to water below 0.3 m inducing water stress resulting in yield reduction. Tractors used for farm operations only compact one side of the bed, however, both sides are compacted in the absence of permanent wheel tracks. By comparison a dual tyre round module cotton picker weighing ∼32 Mg compacts 67 % of the rows on both sides and 33 % on one side suggesting greater economic loss in the following season compared to that estimated from the current study. Reductions in soil water recharge following irrigation and rainfall events due to compaction will further decrease farm efficiency and profitability. To our knowledge this is the first study related to soil compaction in any crop to show the direct relationship between yield, plant stress time and soil water dynamics at specific depths in profile. It is suggested that short term agronomic decisions (eg irrigation scheduling) need to be considered differently where compaction has been identified as limiting productivity. We recommend case studies be conducted to monitor the effect of compaction on commercial farm productivity and to demonstrate the cost of compaction across agricultural industries to drive practice change. Demonstrating the potential economic consequences of soil compaction by the integrated approach used in this study may encourage practice change to minimize compaction on farms.

农业机械尺寸的增加提高了农场效率，但存在土壤板结的风险。在这里，我们提出了一种新方法，通过持续监测作物冠层温度和土壤剖面水分并测量单个作物行的作物产量来确定对棉花种植系统的经济影响，来研究田间交通压实的影响。由于较低的作物高度、叶面积、生物量和果实数量，植物行两侧重量为 19.2 毫克的拖拉机的运输使皮棉产量降低了 27%。与非压实地块相比，压实地块中升高的冠层温度 (Tc) 导致胁迫时间（即当 Tc 高于棉花生长的最佳 Tc 时的累积时间）增加 30%。在 0.3-0.5 m 和 0.5-0.7 m 深度，压实地块中较高的应力时间与作物用水量（根据土壤水分变化估计）分别减少 72% 和 27% 相关。由于压实，灌溉和降雨在土壤剖面中的水补给减少了 16%，在 0.3 – 0.5 m 深度减少了 86%。这些结果表明，压实可能会减少根系对 0.3 m 以下的水分的获取，从而导致水分胁迫，从而导致产量下降。用于农场作业的拖拉机仅压实床的一侧，但是，在没有永久性轮轨的情况下，两侧都被压实。相比之下，重约 32 Mg 的双轮胎圆形模块采棉机压实了两侧 67% 的行，一侧压实了 33%，这表明与当前研究估计的相比，下一季的经济损失更大。由于压实导致灌溉和降雨事件后土壤水分补给减少将进一步降低农场效率和盈利能力。据我们所知，这是第一项与任何作物的土壤压实相关的研究，以显示产量、植物胁迫时间和剖面特定深度的土壤水分动态之间的直接关系。建议在压实被确定为限制生产力的情况下，需要不同地考虑短期农艺决策（例如灌溉计划）。我们建议进行案例研究，以监测压实对商业农场生产力的影响，并展示整个农业行业的压实成本，以推动实践变革。通过本研究中使用的综合方法证明土壤压实的潜在经济后果可能会鼓励实践改变，以尽量减少农场的压实。