Abstract The study estimated infiltration-excess runoff properties of three floodplain soil-types under aquifer water management at Anglo American Kolomela Iron Ore mine in Postmasburg, Northern Cape Province of South Africa. Rainstorm regimes of amounts 60 (high), 30 (medium), and 15 (low) mm with respective intensities of 1.61, 0.52, and 0.27 mm min−1 were simulated on 1 m2 plot with 1% slope. Infiltration-excess runoff properties were affected by a rainstorm, but not soil-type. When combined with rainstorm, soil-type affected accumulative run-off rates. High rainstorm had different (p ≤ 0.05) accumulative runoff rates (0.1–0.61 mm min−1) and increased with clay content. Different response times of 4, 10, and 17 min for respective high, medium, and low rainstorms were quickest on higher clay plus silt content and bulk-density under high and lower rainstorms, respectively. Lower rainstorms had similar effects on accumulative runoff rates (0.01–0.05 mm min−1), total runoff yield (0.59–18 mm), and runoff coefficients (4.29–18%). Under the high rainstorm, total runoff yields (11.4–25.8 mm) and runoff coefficients (19–42.9%) were different and increased with clay plus fine-silt content. Although simulated rainstorms had constant intensities, results showed high rainstorms to be of primal influence on infiltration-excess runoff. Clay plus silt content and bulk-density influenced infiltration-runoff properties for respective high and lower rainstorms. Apart from rainstorm characteristics, surface clay plus silt content and bulk-density are important for harnessing surface runoff in floodplains for aquifer recharge.

中文翻译：

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模拟降雨条件下旱地漫滩土壤类型的入渗-过量径流特性

摘要 本研究估计了南非北开普省 Postmasburg 英美科洛梅拉铁矿在含水层水管理下的三种漫滩土壤类型的入渗-过剩径流特性。在坡度为 1% 的 1 平方米地块上模拟了强度分别为 1.61、0.52 和 0.27 mm min-1 的 60（高）、30（中）和 15（低）mm 的暴雨状态。入渗过量径流特性受暴雨影响，但不受土壤类型影响。当与暴雨相结合时，土壤类型会影响累积径流率。高暴雨具有不同的 (p ≤ 0.05) 累积径流速率 (0.1–0.61 mm min-1) 并随着粘土含量的增加而增加。4、10 和 17 分钟的不同响应时间分别对应高、中、和低暴雨分别在高和低暴雨下在较高的粘土和淤泥含量和容重上最快。较低的暴雨对累积径流速率（0.01-0.05 mm min-1）、总径流产量（0.59-18 mm）和径流系数（4.29-18%）有类似的影响。在强暴雨下，总径流产量（11.4-25.8 mm）和径流系数（19-42.9%）不同，并随着粘土和细粉砂含量的增加而增加。虽然模拟的暴雨强度恒定，但结果表明，高暴雨对入渗过量径流产生了主要影响。粘土加淤泥含量和堆积密度影响了各自的高暴雨和低暴雨的渗透径流特性。除了暴雨的特点，