Assessment of heavy metals in sediment of Aguamilpa Dam, Mexico

Abstract

The Aguamilpa Dam is part of the reservoir cascade system formed by four reservoirs in the middle and lower part of the Santiago River. For decades, this system has received urban and industrial wastewater from the metropolitan area of Guadalajara and the runoff of agricultural fields located in the river basin. The present study was carried out to obtain a preliminary assessment on the concentration distribution of heavy metals (Al, Ba, Cd, Cr, Cu, Fe, Hg, Mg, Ni, Pb, and Zn) in surface sediments of the Aguamilpa reservoir collected from 10 sampling stations. The metal concentrations (mg kg(-1)) in the sampling stations ranged as follows: Al, 27,600-7760; Ba, 190.0-15.9; Cd, 0.27-0.02; Cr, 18.30-0.22; Cu, 60.80-0.79; Fe, 15,900-4740; Hg, 0.04-0.01; Mg, 7590-8.05; Ni, 189.00-0.24; Pb, 13.6-1.64; and Zn, 51.8-14.8. Significant spatial variation in concentrations was observed for Al, Fe, and Pb. Sediment pollution was evaluated using the enrichment factor, the geo-accumulation index, the pollution load index, and sediment quality guidelines. Based on geo-accumulation and pollution load indexes, Aguamilpa sediments were found, in some sampling stations, as unpolluted to moderately polluted with Ni, Cd, Cu, and Mg. Enrichment factors showed that Cd is highly related to agricultural activities that take place in the surrounding areas of the Aguamilpa reservoir. Despite these results, none of the heavy metals evaluated exceeded international concentrations limits, indicating that the Aguamilpa reservoir surface sediments are not contaminated.

Temporal and Spatial Study of Water Quality and Trophic Evaluation of a Large Tropical Reservoir

“…The ambient temperature is a factor that could be related to the behavior of the water body. The average ambient temperature (at the reservoir area) is almost 20 • C, very similar to those observed by Rangel-Peraza et al [31] for a tropical reservoir located at a subhumid warm climate area with summer rains. Water contributions and extractions were found with no significant monthly variation, as the volume storage of the reservoir was maintained along the period of time included in the study.…”

“…Differences between water quality features were shown in the different sampling sites. This spatial behavior meets the characteristics suggested for reservoir water quality modeling [31].…”

Heavy Metal Concentrations in Water and Sediments From Affluents and Effluents of Mediterranean Chilean Reservoirs

“…It has been estimated that in the world at present there are around 45,000 dams with a water column depth of more than 15 meters 30 . However, there are no systematic studies on the influence of dams on the distribution of heavy metals in sediment, considering that a dam alters the free flow of a river to the sea; only recently has work begun in which the seasonal distribution of heavy metals is studied in a dam 31 . Considering that there are dams in a number of rivers in Chile producing disruption of free water flow, and that mineral salts may accumulate in the zone of the dam 32 , the goal of this study was to determine the concentrations of heavy metals in both water and sediments as a labile fraction (soluble, exchangeable or bonded to carbonate) and pseudo-totals in the affluent and effluent of four reservoirs (Cogotí, Corrales, La Paloma, and Recoleta).…”

Analysis of Heavy Metals in Surface Sediments from Agh Gel Wetland, Iran

“…The clay, sand, silt, and organic particles deposited at the bottom of a water body as sediments come from soil erosion and decay of plants and animals; wind, rain, and anthropogenic activities may carry these particles into aquatic ecosystems especially rivers, lakes, and streams. Once inorganic and organic particulate are in the aquatic environment, heavy metals are adsorbed onto them and are incorporated into sediment resulting in raised levels of heavy metals in bottom sediment [1,2].…”

“…From four decades ago, many efforts around the world have been undertaken to assessment the behavior and distribution of heavy metals in sediments from the aquatic ecosystems [2]. In this regards, geochemical study has been used widely to estimate the impact of human activities and the degree of metal pollution on sediment quality [9][10][11].…”