Groundwater extracted from coal seams may be a resource for irrigation of land in areas with low rainfall, but the effect of this water on soil properties needs to be established. A lysimeter study was conducted using intact soil cores (0.75 m diameter, 1.4 m deep) of four different soil types (Sodic Vertisol, Calcic Solonetz, Haplic Solonetz and Xanthic Lixisol) from southern Queensland, Australia, to study changes in soil physical and chemical properties under accelerated rates of irrigation with coal seam (CS) water (electrical conductivity (ECw) of 3 dS/m, pH of 8.8, and a sodium adsorption ratio (SAR) of 100). Cores were also alternately irrigated with deionised water to simulate rainfall, and either lucerne (Medicago sativa L) or Rhodes grass (Chloris gayana Kunth.) where grown in the lysimeters. The soil surface was treated with stoichiometric rates of elemental sulfur (1.4 t/ha) and gypsum (2.5 t/ha) prior to every 450 mm CS water irrigation to minimise changes in SAR and pH. Three of the soils (Vertisol, both Solonetz) had low leaching fractions (≤ 0.1 %) due to their clay texture and were initially saline in the subsoil (ECse 1.4–4.4 dS/m). Irrigation with CS water resulted in a gradual increase in salt content (EC) and SAR throughout the soil profile, but pH was not increased due to surface-applied elemental sulfur. The Lixisol had a higher hydraulic conductivity and leaching fraction (6.7 %) due to is loamy texture – in this soil, accumulated salts could be leached and no increase in salinity or pH were measured. Despite an increase in SAR for this loamy soil, no structural degradation was observed, and it could be sustainably irrigated with up to 3200 mm CS water (with cumulative irrigation volume of 5400 mm). Hence, leaching fractions rather than soil chemistry are good indicators to identify soils suitable for irrigation with CS water that is saline, alkaline, and sodic.

中文翻译：

---

煤层水灌溉牧场土壤 - 土壤理化性质的溶度计研究


从煤层中提取的地下水可能是降雨量少地区灌溉土地的资源，但需要确定这种水对土壤特性的影响。使用来自澳大利亚昆士兰州南部的四种不同土壤类型（钠垂直素、钙化 Solonetz、单倍索洛内茨和 Xanthic Lixisol）的完整土壤芯（直径 0.75 m，深 1.4 m）进行溶度计研究，以研究在煤层 （CS） 水加速灌溉速率下土壤物理和化学性质的变化（电导率 （ECw） 为 3 dS/m， pH 值为 8.8，钠吸附比 （SAR） 为 100）。岩芯也用去离子水交替灌溉以模拟降雨，并在溶出仪中生长苜蓿 （Medicago sativa L） 或罗得草 （Chloris gayana Kunth.） 生长。在每 450 mm CS 灌溉之前，用元素硫 （1.4 t/ha） 和石膏 （2.5 t/ha） 的化学计量速率处理土壤表面，以尽量减少 SAR 和 pH 值的变化。其中三种土壤（Vertisol，均为 Solonetz）由于其粘土质地而具有低浸出分数 （≤ 0.1 %），并且最初在底土中是盐分 （ECse 1.4–4.4 dS/m）。用 CS 水灌溉导致整个土壤剖面的盐含量 （EC） 和 SAR 逐渐增加，但由于表面施用的元素硫，pH 值没有增加。由于质地肥沃，Lixisol 具有较高的水力传导率和浸出分数 （6.7%）——在这种土壤中，积累的盐分可以浸出，并且没有测量到盐度或 pH 值的增加。尽管这种壤土的 SAR 增加，但没有观察到结构退化，并且可以用高达 3200 毫米 CS 的水（累积灌溉量为 5400 毫米）进行可持续灌溉。 因此，浸出馏分而不是土壤化学是确定适合用含盐、碱性和钠 CS 水灌溉的土壤的良好指标。