General Quality Index Research Articles

Influence of urbanization and tourist activities on the water quality of the Potrero de los Funes River (San Luis – Argentina)

A study of the water quality of the Potrero de los Funes River (San Luis - Argentina) was carried out in order to evaluate the possible effect of the anthropogenic activities on the river developed in the homonymous town. Samples were collected during the period March 2000-November 2005 at three selected sampling sites (RP(1), RP(2) and RP(3)). Different physicochemical and bacteriological parameters (turbidity, pH, conductivity, suspended solids, alkalinity, potassium, sodium, calcium, magnesium, chlorides, nitrates, phosphates, sulphates, chemical oxygen demand (COD), 5-day biological oxygen demand (BOD(5)), dissolved oxygen, total coliforms, Escherichia coli and total heterotrophic bacteria) were analysed according to the Standard Method for the Examination of Water and Wastewater. When comparing the values of total coliforms, E. coli, total heterotrophic bacteria, COD, BOD(5) and phosphates from the zone without anthropogenic influence (RP(1)) and the urban zones (RP(2) and RP(3)) an important variation in the parameters was observed. These results indicate that the urban activity produces a serious and negative effect on the water quality, thus constituting a sanitary risk and may have a major impact on the trophic status of the Potrero de los Funes dam. As case study, we report on the use of General Quality Index (GQI) to evaluate spatial and seasonal changes in the water quality of Potrero de los Funes River. Results revealed a significant degradation of the water quality at RP(2) and RP(3).

Developing a multifunctional tree‐structured quality index for soil management

PurposeAn extensive knowledge of soil characteristics and an awareness of the type and amount of pollutants present are essential to evaluate the utilization potential of soil resources for various land uses. On the other hand, for management and decision‐making purpose, there is a need to develop concise indices in order to adequately express the overall quality of soil resources. The aim of this study was to introduce a flexible soil quality index system, mainly based on fertility and the presence of pollutants.Design/methodology/approachA tree‐structured approach was adopted, leading to a concise final index from various intermediate sub‐indices. More specifically, a number of physical‐chemical‐biological parameters lead to an agronomic quality index (AQI). Another group of parameters referring to polluting substances of various origins are combined to give a multifunctional quality index (MQI). AQI and MQI are then coupled into an overall general quality index. The proposed model was implemented by using a set of data concerning various specific sites throughout Italy.FindingsThe proposed methodology proved useful in providing valuable and quick information about the overall soil quality performance and its main sources, and in helping to balance the contrasting needs of obtaining concise quantitative information, on the one hand, and of minimizing the inevitable loss of information inherent in every process of synthesis, on the other hand.Originality/valueThis paper presents an innovative quality index structure for the environmental and multifunctional management of soil, whose main value is related to its flexibility (e.g. different number and kind of parameters, various levels of aggregation) which makes it applicable to various contexts.

Development of a sensor array based measurement system for continuous monitoring of water and wastewater

Non-specific sensor arrays provide a simple, non-invasive technique for monitoring changes in water and wastewater quality. An on-line measurement system that incorporated an array of conducting polymers was tested for continuous analysis both in a laboratory, and in the field. The headspace gas, generated from a sparged liquid sample within a temperature-controlled flow-cell was directly transferred to the sensor chamber for analysis. Experiments were statistically designed to investigate the reproducibility of the sensor responses due to humidity effects. The combined effect and interactions of temperature throughout the system, gas flow rate and sparger porosity were evaluated. An optimal sampling methodology was developed for water and wastewater samples. Selected methodologies were applied to a continuous monitoring system. Results showed high-resolution profiles from laboratory and field trials underlining the potential of the technique for the detection of sudden changes in the odour profile. The interest of appropriate data analysis protocols and of a general quality index for real-time monitoring of water and wastewater is also discussed.