Correlation of soil salinity and nitrate with irrigation from the major aquifers

Abstract

This dissertation investigates the relationship between key chemicals in agricultural soil and the ground water used to irrigate it. Moreover, the same chemical properties were analysed in agricultural non-irrigated soil and natural soil. The fundamentally aim was to observe any significant relationship between these conditions as they vary across the year from summer to winter. In order to conduct this study, 22 locations across different aquifers in Malta were chosen for sampling from areas situated over perched, coastal, and mean-sea level aquifers. Proceeding the data collection, the samples were further analysed in the laboratory for the key chemical components, being; pH, electrical conductivity, NO3-, NH4+, Phosphorous. The results obtained from the laboratory analysis were used to investigate the relationship between the soil and irrigation ground water as it varies between the soil parameters and over seasons. This was done through the use of visual data representation and statistical tests. The main findings of the study show that the significance in the relationship between ground water and agricultural irrigated soil is somewhat subjective to the conditions and chemical property being studied. The results illustrated that the local ground water conditions undergo significant change between summer and winter. Most notably, the outcome of the study showed that most of the change in chemical properties occurred in agricultural irrigated soil rather than nonagricultural soils. The conclusion of this study indicates that there is the need for further education in ground water abstraction, both on domestic and agricultural levels. Soil quality can be further improved with proper soil management and ground water abstraction practices.