# Fire-Induced Changes in Soil and Implications on Soil Sorption Capacity and Remediation Methods
## 3 Fire-Induced Changes in Soil Properties and the Implications on Soil Sorption Capacity  
Fire affects soil physical, chemical, mineralogical and biological properties to different extents depending on the temperature to which the soil is raised during fire incidents. Soil physical properties commonly affected by fire include moisture content, color, structure, aggregate stability, water repellency, and texture [26; 48; 49; 50]. Details of the effects of fire on these soil physical properties have been reported by several authors [26; 48; 49; 50; 56; 57; 58; 59; 60; 61; 62; 63; 64; 65; 66; 67; 68; 69]. Soil chemical properties are affected at temperatures as low as 50 \({}^{\circ}\)C, where soil moisture characteristics start undergoing changes up to temperatures above 700 \({}^{\circ}\)C, where oxyhydroxides and carbonates are converted to oxides and the pH of the soil increases as a result of the accumulation of ash [10]. Soil chemical properties said to be affected by fires include soil pH [16; 26; 49; 70; 71; 72; 73; 74; 75], nutrient content [26; 76; 77; 78], organic matter content and cation exchange capacity [10; 79; 80; 81; 82; 83; 84; 85], and major and trace element oxide concentrations [16; 26; 44; 49; 76; 77; 78; 86; 87; 88; 89; 90; 91; 92; 93; 94; 95; 96]. Fire-induced soil mineralogical changes occur both at low and high fire intensities, and are concentrated where the fire is intense and of a longer duration. These changes have been reported by [PERSON] [31], [PERSON] [44], [PERSON] et al. [97], [PERSON] et al. [50], [PERSON] and [PERSON] [98], [PERSON] et al. [67], [PERSON] and [PERSON] [99], [PERSON] et al. [31], [PERSON] et al. [51], [PERSON] et al. [100], [PERSON] and [PERSON] [16], [PERSON] [101], and [PERSON] and [PERSON] [66]. Fire also affects soil biological properties [102; 103; 104; 105; 106; 107; 108; 109]. Changes in these properties affect several soil chemical processes including sorption processes in different ways.  
The removal of a compound from solution to solid phase is described as sorption [110]. Sorption of contaminants by soil reduces their mobility in the soil environment and consequently the risks that they pose to various environmental receptors. Soil sorption processes play a significant role in the maintenance of proper soil structure, supply of plant nutrients, their migration and bioavailability, and the mobility, dissolution and neutralization of contaminants in the soil environment [111]. Soil is a complex heterogeneous material with peculiar properties which make up its sorption complex.  
The total sorption capacity of a soil is a function of the sum of the individual sorption capacities of various soil components (clay content, organic matter content, and sesquioxizes) and properties including soil texture, cation exchange capacity (CEC), mineralogy, and pH [112]. Soil sorption behavior is therefore described as complex, and anything affecting any one of these soil components or properties is likely to affect soil sorption complex and its sorption capacity. Changes in soil temperature caused by fire affects these soil properties and consequently soil sorption capacity in different ways. This section of the review looks at fire-induced changes in soil properties that make up its sorption complex and the implications of these changes on its sorption capacity.