Department of Geology and Geoenvironment, University of Athens, Athens, 15784, Greece.
Soil Science Laboratory, Aristotle University of Thessaloniki, Thessaloniki, 54124, Greece.
Chemosphere. 2018 Nov;210:597-606. doi: 10.1016/j.chemosphere.2018.07.046. Epub 2018 Jul 11.
Toxic chromium [(Cr(VI)] in food chain has created an alarming situation for human life and ecosystems. The present study through a greenhouse pot experiment aims to (a) investigate the ability of organic matter in reducing Cr uptake by lettuce (Lactuca sativa L.) from a sandy loam soil irrigating with Cr(VI)-water, (b) to provide a way for the restriction of Cr transfer from contaminated soils and irrigation water to plants/crops and (c) to contribute to the better management of soil (land) and water use, without reduction of the agricultural production. Since soil and groundwater contamination by Cr is a potential risk in a worldwide scale, due to industrial activities and/or natural processes, organic carbon may play a key role in the mobility of added Cr(VI) to soil via irrigation water, in a significant way. The cultivation of lettuce, using organic matter in the form of leonardite (10 and 30 wt%) and Cr(VI)-irrigation water (100, 200 and 300 mgL), showed that the uptake of Cr in both shoots and roots increased with increasing concentration of Cr in the irrigation water. The highest Cr values in shoots (average = 10 mg/kg) and in roots (average = 28 mg/kg) were recorded in those plants cultivated in soil after the addition of Cr(VI)- water without organic matter, whereas the lowest Cr values in shoots (average = 0.44 mg/kg) and in roots (average = 0.7 mg/kg) were recorded in those plants cultivated in soil with addition of 30 wt% organic matter. The used leonardite as organic matter that is an oxidized form of lignite, due to its high content of humic acid is considered to be a useful organic fertilizer that provides possibilities for combining food production with soil protection. Therefore, the application of the natural organic material leonardite, as a land management technique, seems to be a cost-effective method consistent to related protocols for the protection of the soil quality.
食物链中的有毒铬 [(Cr(VI)] 对人类生命和生态系统造成了令人担忧的局面。本研究通过温室盆栽实验，旨在：(a) 研究在以 Cr(VI)-水灌溉的砂壤土中，通过施用有机物来降低生菜 (Lactuca sativa L.) 对铬的吸收能力；(b) 为限制 Cr 从污染土壤和灌溉水中向植物/作物的转移提供一种方法；(c) 有助于更好地管理土壤（土地）和水资源利用，而不降低农业产量。由于 Cr 对土壤和地下水的污染是一个全球性的潜在风险，这是由于工业活动和/或自然过程造成的，有机碳可能会通过灌溉水在很大程度上对添加到土壤中的 Cr(VI)的迁移性起到关键作用。使用褐煤制成的有机物（10 和 30 wt%）和 Cr(VI)-灌溉水（100、200 和 300 mg/L）来种植生菜的结果表明，随着灌溉水中 Cr 浓度的增加，生菜地上部和根系对 Cr 的吸收都有所增加。在未添加有机物的情况下，用添加了 Cr(VI)-水的土壤种植的生菜地上部（平均=10 mg/kg）和根系（平均=28 mg/kg）中的 Cr 含量最高，而在添加了 30 wt%有机物的土壤中种植的生菜地上部（平均=0.44 mg/kg）和根系（平均=0.7 mg/kg）中的 Cr 含量最低。所用的褐煤作为有机物是褐煤的氧化形式，由于其腐殖酸含量高，被认为是一种有用的有机肥，为将食品生产与土壤保护结合起来提供了可能性。因此，应用天然有机物质褐煤作为土地管理技术，似乎是一种符合土壤质量保护相关协议的具有成本效益的方法。
