Industrial Impact on Marsh Soils at the Bahia Blanca Ria, Argentina

Abstract

The Bahia Blanca Estuary is located in southern Buenos Aires province, Argentina. The area is linked to a petrochemical industrial complex, whose raw materials and final products contaminate the surrounding areas via atmospheric pollution and effluents, which are dumped in the estuary waters. To establish the effects of the industrial waste disposal on the nearest coastal soils, 17 samples were taken at different distances from the loading dock and the outfall pipes of the industrial complex. Later, the physicochemical characteristics of the soil samples, their hydrocarbon contents, sulfides, sulfates, Zn, Cu, and Pb were analyzed and a comparison was made to control samples, which were not affected by the industrial outfall. Hydrocarbons, Zn, Cu, and Pb contents were found at levels that modified the physical and chemical characteristics of the soils. The resistance to penetration shows that the thinner the film of water that surrounds the particles or aggregates, the smaller the migration of organic micelle, which settle on the surface of the contact material. This is demonstrated by the degree of cohesion reached by the particles and the strong influence on the index of hydrophobicity. The high porosity shows that the continuity of the porous space of the soil matrix is impeded by the presence of pollutants, which generate areas that are highly limiting to water flow. The oxidation-reduction potential and the low concentrations of soluble forms of Cu and Pb compared with their concentrations precipitated as sulfides confirm the action of the pollutants.

Degradation of fuel oil in salt marsh soils affected by the Prestige oil spill

“…The crust consisted of aggregates of fine material bound by the oil, which, in coating the finer particles, must have facilitated their penetration and permanence in the larger pores and channels, thereby "gluing" larger particles together and reducing porosity and permeability while increasing resistance to penetration. Under normal circumstances, particles in sandy salt marsh soils reorganize during each cycle of wetting and drying rather than adhering to each other, which results in a very low resistance to penetration [43][44][45]17].…”

Enrichment of marsh soils with heavy metals by effect of anthropic pollution

“…Marshes, which constitute an important component of river, estuarine and coastal ecosystems, are extremely sensitive to pollution [1][2][3][4][5]. Agricultural and urban waste is often responsible for the origin of heavy metals entering the marine environment and reaching soils and sediments [1][2][3][4][5].…”

“…Agricultural and urban waste is often responsible for the origin of heavy metals entering the marine environment and reaching soils and sediments [1][2][3][4][5]. The oxidation status of soils and sediments affects the distribution of some trace metals between bound, unavailable forms and soluble, available forms [1,2,5]. A combination of anaerobic conditions and high matter contents makes a salt marsh the ideal medium for bacterial reduction of sulphate to sulphide [6].…”

“…A combination of anaerobic conditions and high matter contents makes a salt marsh the ideal medium for bacterial reduction of sulphate to sulphide [6]. In fact, sulphidization plays a prominent role in the development of marsh soils and the control of heavy metal solubility [1,2,5]. Salt marsh soils generally have low bulk densities (by effect of waterlogging), high contents in organic matter-which often comes from agricultural and urban waste in addition to marsh plant residues-and high sulphide contents [1,2,5,7].…”

Impact of industrial and urban waste on the heavy metal content of salt marsh soils in the southwest of the province of Pontevedra (Galicia, Spain)

“…Thus, the oxidation status of soils and sediments affects the distribution of some trace metals between bound, unavailable and available forms. Salt marsh soils generally have low bulk densities -as a result of waterlogging-, high contents in organic matterwhich often comes not only from marsh vegetation residues, but also agricultural and urban waste-, and high sulphide contents (Griffin and Rabenhorst, 1989;Andrade et al, 2002Andrade et al, , 2004. The redox potential play a decisive role in the fate of heavy metals as it dictates their distribution among available and insoluble forms (Griffin and Rabenhorst, 1989;Gambrell et al, 1991).…”