The relationship between abiotic factors and biodiversity at Salina Nature Reserve

Abstract

Salinas are often constructed on the sites of former wetlands. Nonetheless, they are of high conservation value as they serve as habitats for a variety of biota. Therefore, the study of salinas and their ecosystem is fundamental due to their high ecological importance. The aim of this project was to examine the relationship between abiotic factors and biodiversity at Salina Nature Reserve (SNR), Malta. The study extended from 25 July 2022 to 3 April 2023. During this period, the SNR was visited approximately monthly and in situ measurements of water temperature, electrical conductivity (EC), pH, nitrate concentration and phosphate concentration carried out. A pH logger was installed in one of the salt pans, recording the pH at 90-minute intervals for the whole duration of the study. During each visit, phytoplankton samples were collected and examined in the laboratory. The results suggested that the EC in a pan is significantly related to its distance from the sea and to the surface area of each pan. No discernible trends were noted for nitrate and phosphate concentrations. Diurnal and seasonal variation in pH was closely correlated with expected fluctuations based on insolation. The density of plankton peaked during periods of warmer temperatures and declined during colder periods. This phytoplankton density was significantly correlated with water temperature and had a positive but non-significant correlation with insolation. No significant correlations were identified between phytoplankton density and nitrate and phosphate concentrations respectively. This study has generated baseline data which could be further developed and researched in future studies and will also benefit the management of SNR.