A spatial interpolation approach for environmental assessment of aquaculture effects on water quality of Pagasitikos Gulf (Eastern Mediterranean).

The impact of fish farming on the physicochemical and biological parameters of the water column was investigated between July and October 2021, in Pagasitikos Gulf. For this purpose, a sampling strategy based on Geographical Information System (GIS) was developed and a grid of 28 sampling stations was created for in situ measurements. The method of spatial interpolation and especially the Radial Basis Function (RBF) was used to estimate the spatial distribution of DO, chl α and nutrients by means of GIS. General Linear Model (GLM) analysis showed significant differences for all measured parameters except for NO3. Nutrients remained at low concentrations without exceeding the permitted limits for eutrophication and welfare of cultivated organisms. GIS exhibited high usefulness for data analysis, with further studies warranted for its optimization on applications related to the environmental impact of fish farming.

Groundwater hydrogeochemistry of Trikala municipality, central Greece.

Sixty-four samples from the groundwater resources of Trikala municipality, central Greece, were collected during two periods (2006 and 2007) and analyzed for physico-chemical parameters (temperature, pH, specific electrical conductivity, and total dissolved solids), major ions (Ca(2+), Cl(-), HCO(3)(-), K(+), Mg(2+), Na(+), NO(3)(-), SO(4)(2-)), and several potentially toxic elements (Al, B, Ba, Br, Ca, Ce, Cl, Cr, Cu, Fe, K, La, Li, Mg, Mn, Mo, Na, Nd, Ni, P, Pb, Rb, S, Sc, Si, Sn, Sr, U, V, Y, Zn). European Council directives and USEPA guidelines were used to assess the water quality. The results indicate that all samples are fresh water, suitable for human consumption. All basic ions and physico-chemical parameters have average concentrations below their recommended optimum limits with the exception of electrical conductivity, for January 2007, and nitrate for October 2006 and January 2007 sampling periods. This exceedance is the result of dissolution of minerals such as calcite and dolomite that are present in the surrounding rocks and the application of fertilizers, respectively. Lead is the only element with an average value that exceeds the recommended EC guideline, while special attention should be paid to one borehole (T9) which has elevated NO(3)(-) values which may pose a risk to human health.