The impact of warfare on the soil environment

One of the most dramatic ways humans can affect soil properties is through the performance of military activities. Warfare-induced disturbances to soil are basically of three types – physical, chemical, and biological – and are aimed at causing direct problems to enemies or, more often, are indirect, undesired ramifications. Physical disturbances to soil include sealing due to building of defensive infrastructures, excavation of trenches or tunnels, compaction by traffic of machinery and troops, or cratering by bombs. Chemical disturbances consist of the input of pollutants such as oil, heavy metals, nitroaromatic explosives, organophosphorus nerve agents, dioxins from herbicides, or radioactive elements. Biological disturbances occur as unintentional consequences of the impact on the physical and chemical properties of soil or the deliberate introduction of microorganisms lethal to higher animals and humans such as botulin or anthrax. Soil represents a secure niche where such pathogens can perpetuate their virulence for decades.Soil morphology, composition, and biology can be profoundly modified by warfare activities in either wartime or peacetime (e.g. at test-firing facilities), and complete recovery of some characteristics can require years or even centuries. A few soil functions can be definitively compromised, if appropriate reclaiming techniques are not carried out. Such techniques often are extremely expensive, as in the case of contamination by dioxins or radionuclides, and remediation can even impel the complete removal of the polluted soil and its substitution with soil material from elsewhere. Taking into account how much of the pedosphere is currently and was in the past involved in warfare, warfare is actually a major means by which humans play a recognized role as a soil forming factor, as well as the parent material, topography, time, climate, and organisms not endowed with the power of reason. The variegated impact of warfare on the soil environment is reviewed here.