Variations in time and space of some physical and chemical variables in the Bernesga river (León, Spain)

The chemical composition of the river Bernesga has been evaluated throughout four seasonal sampling studies at twelve sampling points. The tendency towards an increase in mineralization all along the river can be observed when using a principal component analysis to the complete data gathered. A temporal differentiation based on the variations which affect the flow rate through out the year is also established. The spatial organization defined by the second component enables us to use the scores as the starting point in order to determine the value of the chemical distance between the different sampling stations. The contrast between the chemical and actual distance gives an overall view of the river, which is a reflection of what happens on its course with regard to its chemical processes