Abstract

Constructed wetlands (CW) containing clinoptilolite zeolite and planted with five halophytes (Sesvium portulacastrum, Juncus effusus, Suaeda monoica, Inula crithmoides and Sarcocornia fruticosa) were irrigated with treated dairy farm effluent. The CW were operated for two years with retention time ranging from 2 to 7 d. Plant species did not affect SAR which was reduced in all treatments from 4.85 to 2.59 (mmol/L)^0.5 due to ion exchange in zeolite. Halophytes increased evapotranspiration to 30 mm d⁻¹ which countered sodium removal. Zeolite planted with Sesuvium portulacastrum had 15% lower sodium percentage (ESP, F_1,118 = 12.53, p = 0.0006) and 5% higher calcium percentage (F₁,₁₁₈ = 7.44, p = 0.007) compared to non-planted zeolite, indicating reconditioning of zeolite with respect to sodium. Enhancement of SAR removal capability by reconditioned zeolite was demonstrated in 24 h batch experiments on excavated zeolite (n = 6) with saline water (SAR = 0, 17.6, 62.8, and 122.8 (mmol/L)^0.5). Zeolite from Sesuvium planted CW reduced SAR to a greater extent than non-planted zeolite and was significant for inlet SAR 17.6 which was reduced to 3.33 ± 0.3 (mmol/L)^0.5 compared to 3.68 ± 0.12 by non-planted zeolite (p < 0.05). In-situ biological reconditioning of active matrix in CW by tailored macrophytes is a novel strategy that may be applicable to other pollutants.

摘要

人工湿地 (CW) 含有斜发沸石沸石，并种植了五种盐生植物（马齿苋、蓼草、Suaeda monoica、Inula crithmoides和Sarcocornia fruticosa），用处理过的奶牛场污水进行灌溉。CW 运行了两年，保留时间为 2 至 7 天。由于沸石中的离子交换，植物种类不影响 SAR，其在所有处理中从 4.85 降低到 2.59 (mmol/L) ^0.5。盐生植物将蒸散量增加到 30 mm d ^-1，这会抵消钠的去除。用马齿苋种植的沸石的钠含量降低了 15%（ESP，F _1,118 = 12.53，p = 0.0006) 和 比未种植沸石高 5% 的钙百分比 (F ₁ , ₁₁₈  = 7.44, p = 0.007)，表明沸石相对于钠的修复。在 用盐水 (SAR = 0、17.6、62.8 和 122.8 (mmol/L) ^0.5 )对挖出的沸石 ( n = 6) 进行的24 小时批量实验中证明了再生沸石对 SAR 去除能力的增强。来自Sesuvium种植的 CW 的沸石比未种植的沸石在更大程度上降低了 SAR，对于入口 SAR 17.6 显着降低至 3.33 ± 0.3 (mmol/L) ^0.5，而未种植的沸石为 3.68 ± 0.12 ( p  < 0.05) ）。原位 通过定制的大型植物对 CW 中的活性基质进行生物修复是一种可能适用于其他污染物的新策略。