Biomonitorización de contaminantes atmosféricos mediante la utilización de hypnum cupressiforme hedw. En la comunidad foral de Navarra y zonas limítrofes

Resumen

BIOMONITORIZATION OF ATMOSPHERIC POLLUTANTS USING HYPNUM CUPRESSIFORME HEDW. IN NAVARRA AND SURROUNDING AREAS The present work deals with the study of air pollution in Navarra, focusing on the characterisation of heavy metals and nitrogen deposition in it. To achieve this goal, four studies have been carried out in four different locations using the bryophyte species Hypnum cupressiforme Hedw. as biomonitor. The first section has been focused on the study of the dynamic and the behaviour of heavy metals and nitrogen in Bertiz Natural Park -a presumedly well-conserved, non-polluted forest catchment- according to their levels in mosses and topsoils samples. In the second study, the concentrations of heavy metals and nitrogen in bryophytes and topsoil samples have been determined in the north of Navarra, along with their main sources and background levels, and the most affected areas in the region. Once that the influence of industrial activity in the Basque Country on the pollution levels detected in the northwestern area of Navarra was confirmed, heavy metal and nitrogen concentrations have been determined in Hypnum cupressiforme Hedw. samples from the surroundings of two steel works located in Zumarraga and Azkoitia: This helped to establish the contamination rate in both areas, the dynamic of the different elements and the range of impact of the atmospheric emissions from both factories. Finally, a work in a remote Pyrenean area has been developed focusing on the study of long-range transboundary air pollution, owing to the increasing interest of the European Comunity and many scientific groups on the issue. Moss samples analysis, collected in a transect in the montainous pass of Larra, has revealed high levels of nitrogen and some anthropogenic metals in the area, confirming the influence of long-range transboundary pollution in the Pyrenees. In general terms, Hypnum cupressiforme Hedw. has proved to be a good biomonitor to evaluate heavy metals atmospheric deposition in regions with different areas and characteristics. However, the use of bryophytes to biomonitor nitrogen deposition has not showed very positive results, except for the sites where nitrogen leveles were high enough to produce an accumulation of this element in terrestrial mosses.