The use of reclaimed water to cope with water scarcity has become one of the main alternative resources in water-deficit countries. Reclaimed water represents a significant component in integrated water resources management in the city of Madrid (Spain). Madrid City Council replaced the usual drinking water irrigation system by a reclaimed water one. This study assessed the effects of reclaimed water irrigation on micronutrient concentration (B, Cu, Fe, Mn and Zn) in the soil–plant system of two urban green areas in Madrid. Results showed that reclaimed water used in Madrid was adequate for irrigation regarding the studied micronutrients. Nevertheless, micronutrient concentration were slightly higher in reclaimed water than in drinking water. Soil organic matter (SOM) and pH had strong influence in some of the micronutrient concentrations in soils and in its bioavailability and transference to cedars (SOM ↔ B _Soil, Cu _Soil, Fe _Soil; pH ↔ B _Soil, Fe _Soil, Mn _Soil). There was no significant correlation between micronutrient concentration in irrigation water and in cedar leaves. Thus, foliar concentration of the studied micronutrients did not exceed toxic limits, even after 15 years of reclaimed water irrigation. Moreover, despite one park was irrigated with reclaimed water 10 years more than the other, reclaimed water irrigation plots did not show major differences in micronutrient concentration between the two parks.

中文翻译：

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再生水灌溉后微量营养素浓度评估：马德里绿地的案例研究*

利用再生水解决缺水问题已成为缺水国家的主要替代资源之一。再生水是马德里（西班牙）市水资源综合管理的重要组成部分。马德里市议会用再生水系统取代了通常的饮用水灌溉系统。本研究评估了再生水灌溉对马德里两个城市绿地土壤-植物系统中微量营养素浓度（B、Cu、Fe、Mn 和 Zn）的影响。结果表明，马德里使用的再生水足以灌溉所研究的微量营养素。然而，再生水中的微量营养素浓度略高于饮用水。_土，铜_土，铁_土；pH ↔ B_土壤、Fe_土壤、Mn_土壤）。灌溉水中的微量营养素浓度与雪松叶中的微量营养素浓度没有显着相关性。因此，即使经过 15 年的再生水灌溉，所研究的微量营养素的叶面浓度也没有超过毒性限度。此外，尽管一个公园用再生水灌溉的时间比另一个多 10 年，但再生水灌溉地块并没有显示两个公园之间微量营养素浓度的显着差异。