Acorn germination and oak (Quercus brantii Lindl.) seedling development dramatically affected by spatial position of maternal trees from Ilam gas refinery, Iran

Abstract

Abstract Air pollution from industrial areas is an environmental stress on trees that can seriously endanger the future of forests. Ancient Persian oak trees (Quercus brantii Lindl.) in the semi-arid forests of the Zagros are exposed to various environmental stresses such as air pollution from the Ilam gas refinery, which causes many challenges in forest regeneration and afforestation, thus jeopardizing forest sustainability or restoration. The aim of this study was to investigate the effect of toxic pollutants emitted from a gas refinery operation on seed germination and morphological characteristics of seedlings from maternal trees that are located at different distances (1000, 1500, 2000, 2500 and 10,000\xa0m) and directions (east and west) from the facility. The results showed that oak seedlings grown from acorns collected at a distance of 10,000\xa0m had the highest values in various seed germination and seedling developmental measures and morphological traits such as leaf and root mass, number and length compared to other distances of 1000, 1500, 2000 and 2500\xa0m from the gas refinery. Highest values in seed germination, and seedling emergence and growth occurred at distances furthest from the refineries. Also, direction from the refinery significantly (p\xa0 10,000\xa0m, and especially to the west of gas refineries.