Anthropic interferences in the nutritional status of tree species growing in urban and peri-urban Atlantic forest remnants

Abstract

This study was conducted with the purpose to evaluate the hypothesis that the air pollution deposition in the remaining Brazilian Atlantic Forest surrounded by diversified land uses, has altered the nutritional status of its tree species. The leaf concentrations of macronutrients and micronutrients were determined to estimate Concentration Factors – CF (plant/soil concentration ratios) and leaf nutrient ratios (N/P, N/K, N/Ca, N/Mg, N/S, S/K, S/Ca, S/Mg) of the most abundant tree species found in four remnants at the Metropolitan Region of Campinas, SE Brazil: Cosmopolis, Holambra, Paulínia and Campinas. The leaf samplings occurred during three dry and wet seasons. Multivariate analysis of variance (MANOVA) determined if CF for nutrients and ratios varied between forest remnants and seasons. Variations in CF values indicated that the nutritional status of the forest remnants is defined by both physical/chemical soil attributes and atmospheric deposition. The clay soils of the Campinas forest appeared to provide the highest buffering capacity against acidic deposition and nutritional imbalances induced by the anthropic activities. The air pollution emissions from diversified land uses has increased the CF medians above a reliable baseline of the nutritional plant/soil relationship in the forest remnants studied. Agriculture activities seemed to be responsible for increasing P, K, Ca, and Mg depositions; industries for N, S and Mn depositions; soil resuspension for Ca, Fe and Mg. Considering these sources, Paulínia and Campinas seemed to be the most and least forest remnants affected by air pollution, respectively.