Influence of Pollution on Photosynthesis Pigment Content in Needles of Picea abies and Picea pungens in Conditions of Development of Iron Ore Deposits

We studied photosynthetic pigments in needles of Pісеа аbies and P. pungens in plantings exposed to aerotechnogenic influence of various levels in the big industrial center of steppe zone of Ukraine (Kryvyi Rih). We analyzed the pigment content in needles of the second year of life sampled from 30 to 40-year-old trees of both species in 6 monitoring sites for 5 months. For the needles of P. аbies and P. pungens from all the sites, we noticed the decreasing content of chlorophyll a (to 27.2 and 25.0%, respectively) and chlorophyll b (to 17.9 and 20.0%, respectively) from May till September, in comparison with background territory. At the same time, the content of carotenoids performing the protective function in photosynthetic reactions increased up to 26.1 and 24.0%, respectively. For P. аbies and P. pungens growing in conditions of intensive technogenic pressure, we ascertained that, during investigations, the sum of chlorophylls (a + b) rate decreased to 24.4 and 23.6%, respectively; ratio (a/b) decreased to 11.4 and 12.3%, respectively; ratio (chlorophylls [a + b]/carotenoids) also decreased to 30.1 and 38.0%, respectively, in comparison with plants from the least polluted site. It is shown that the most intensive negative influence on plantings is caused by industrial pollution and exhaust gases: the minimum or, more rarely, the maximum rates of pigment content appeared in needles of the plants exactly from these sites. Our research results demonstrate the feasibility of using the pigment complexes of P. аbies and P. pungens, with the assimilative apparatus sensitive to air pollution damage, as indicators of air environmental conditions.