The Content of Phosphorus in the Needles of Pinus sylvestris L. Affected by Industrial Air Pollution

A facility for disposal of toxic substances had been functioning in Kirov Oblast between 2006 and 2015. Destruction of phosphorus-containing substances resulted in formation of inorganic phosphorus compounds, which could enter the environment as components of gaseous emissions. The aim of the present work was to study the spatial patterns of accumulation of phosphorus compounds in the needles of Pinus sylvestris L. in the production area. The study was carried out at monitoring sites, which were represented by forest communities (southern taiga subzone) located at different distances from the pollution source (0.96–9.63 km). The total phosphorus in second-year pine needles was determined by the spectrophotometric method. During the research period (2011–2017), total phosphorus in the needles of P. sylvestris varied between 730 and 2229 μg/g. Based on results of cluster analysis, the sites were classified into two groups, which differed in levels of phosphorus accumulation in the needles of Р. sylvestris. The first group included sites with increased accumulation of total phosphorus in pine needles, which were located near the source of pollution in the direction of the prevailing winds. In sites belonging to the second group, the needles contained reduced amounts of phosphorus compounds. During the research period, variations in the amount of phosphorus in pine needles followed a similar pattern. From 2011 to 2016, the accumulation of phosphorus in the needles increased at monitoring sites of both groups. A decrease in total phosphorus in needles in 2017 was caused by a decrease in the release of phosphorus compounds to the environment and the involvement of accumulated phosphorus in the life processes of P. sylvestris. The increased accumulation of phosphorus compounds in needles in the sites near the source of air pollution was not favorable for vital processes of P. sylvestris needles and resulted in a reduction in their lifespan. Thus, the needles of P. sylvestris can be used as an accumulative indicator in areas affected by industrial air pollution by phosphorus compounds