Influence of Clay Mineralogy on Soil Dispersion Behavior and Water Quality

Abstract

Influence of Clay Mineralogy on Soil Dispersion Behavior and Water Quality Jessique L. Ghezzi Currently, there is very little research available on nonpoint source pollution from rural watersheds. Government regulatory agencies are desperate for information regarding the causes of nonpoint source pollution, which includes the relationship between suspended soil particles and dispersion. Since soil dispersion is dependent on clay mineralogy, knowing the clay mineralogy of the soil in an area can help predict sediment loads entering the surrounding surface waters. This information is necessary to protect the resource value of our rivers, lakes, and estuaries, as well as to protect recreational activities such as fishing or hunting; but most importantly, this information is necessary to ensure the safety of our drinking water supply. Clay mineralogy and its influence on dispersion, as well as dispersion and its relation to water quality are the focus of this study. Soil mineralogy affects water quality in several ways: soil mineralogy determines the dispersivity of the clay portion of the soil and dispersive clays are likely to end up as suspended sediment in surface waters; weathering reactions contribute elements to water as dissolved load, and the sorption properties of clay minerals contribute to soils' ability to filter and carry pollutants. Through the use of X-ray diffraction, dispersivity, atomic absorption spectrometry, cation exchange capacity, and petrographic microscopy, this study shows that the clay mineral fraction of a soil determines the dispersivity, and that dispersed clay minerals contribute excess nutrients and metals as nonpoint source pollutants to surface waters.v ACKNOWLEDGEMENTS

Variations in Aggregate Stability and selected Soil Chemical Properties Under Different Land Use Systems in Ikpe Ikot Nkon, Southeastern, Nigeria

“…This may be associated with increase in the percentage of binding materials (polysaccharides, humic and humin) contained in the organic materials which enable soil particles to aggregate with each other [33,34]. The higher DR observed in CS may be attributed to the colloidal nature of clay which could promote the poor aggregation in the soils [35]. The organic matter, available phosphorus, total nitrogen and pH of the soils studied are shown in Table 5.…”