Phosphine in soils, sludges, biogases and atmospheric implications—a review

This is a review of previously published and unpublished results of research into the occurrence of phosphine (PH₃) in the environment in the form of matrix bound phosphine in soils, aquatic sediments and sludges (range ng kg⁻¹to μg kg⁻¹), free phosphine in formed biogases (range ng m⁻³ to μg m⁻³) and in the atmosphere (range pg m⁻³ to ng m⁻³).The reviewed data support the hypothesis of the existence of a small gaseous link in the phosphorus cycle, which could become important over the long term.Matrix-bound phosphine in soils can be interpreted as a stationary state concentration of phosphine between production and consumption. This phosphine turnover within the soil may be important even if the stationary state concentration (matrix-bound phosphine) is small. Under such circumstances, a slow migration process of phosphine in the interstitial gas sphere of soils is possible. Such a process would influence the balance of phosphorus in agricultural and wetland soil.The detection of easily oxidizable phosphine as a ubiquitous trace gas in the atmosphere can be interpreted as the residue of an important turnover of phosphine between widely distributed emission sources and sinks such as soils and sediments. The atmosphere can carry gaseous phosphorus to remote places.