Department of Soil, Plant and Food Sciences, University of Bari, Via Amendola 165/A, 70126, Bari, Italy.
Department of Maritime Studies, Piraeus University, Grigoriou Lampraki 21 & Distomou, 18533, Piraeus, Greece.
Chemosphere. 2021 Oct;281:130752. doi: 10.1016/j.chemosphere.2021.130752. Epub 2021 May 3.
In the last years, uncontrolled fires are frequently occurring in forest and agricultural areas as an indirect effect of the rising aridity and global warming or caused by intentional illegal burnings. In addition, controlled burning is still largely used by farmers as an agricultural practice in many parts of the world. During fire events, soil can reach very high temperatures at the soil surface, causing dramatic changes of soil properties and elements biogeochemistry. Among soil elements, also potentially toxic elements (PTEs) can be affected by fires, becoming more or less mobile and bioavailable, depending on fire severity and soil characteristics. Such transformations could be particularly relevant in agricultural soils used for crop productions since fire events could modify PTEs speciation and uptake by plants and associated (micro)organisms thus endangering the whole food-chain. In this review, after describing the effects of fire on soil minerals and organic matter, the impact of fires on PTEs distribution and speciation in soils is presented, as well as their influence on soil microorganisms and plants uptake. The most common experimental methods used to simulate fires at the laboratory and field scale are briefly illustrated, and finally the impact that traditional and innovative agricultural practices can have on PTEs availability in burned agricultural soils is discussed in a future research perspective.
在过去的几年中，由于干旱和全球变暖的加剧，森林和农业地区经常发生失控的火灾，或者是由于故意非法焚烧造成的。此外，在世界许多地区，农民仍然广泛地将受控燃烧作为一种农业实践。在火灾事件中，土壤表面的温度可以达到非常高的水平，导致土壤性质和元素生物地球化学发生剧烈变化。在土壤元素中，潜在有毒元素（PTEs）也可能受到火灾的影响，其迁移性和生物可利用性会发生变化，这取决于火灾的严重程度和土壤特性。这种变化在用于作物生产的农业土壤中可能尤为重要，因为火灾事件可能会改变 PTEs 的形态和植物及相关（微生物）对其的吸收，从而危及整个食物链。在本文中，在描述了火灾对土壤矿物质和有机质的影响之后，介绍了火灾对土壤中 PTEs 分布和形态的影响，以及它们对土壤微生物和植物吸收的影响。简要说明了在实验室和野外尺度模拟火灾最常用的实验方法，最后讨论了传统和创新农业实践对燃烧农业土壤中 PTEs 有效性的影响。
