Microbiological and hydrogeological assessment of groundwater in southern Italy

Abstract

This study represents the first investigation of microbiological groundwater pollution as a function of aquifer type and season for the Apulia region of southern Italy. Two hundred and seven wells were randomly selected from those monitored by the Regional Agency for Environmental Protection for emergency use. Both compulsory (Escherichia coli, Total Coliform, and Enterococci) and optional (Pseudomonas aeruginosa, Salmonella spp., Heterotrophic Plate Count at 37 and 22 °C) microbiological parameters were assessed regularly at these wells. Groundwater from only 18 of the 207 (8.7 %) wells was potable; these all draw from karst-fissured aquifers. The remaining 189 wells draw from karst-fissured (66.1 %) or porous (33.9 %) aquifers. Of these, 82 (43.4 %) tested negative for Salmonella spp. and P. aeruginosa, while 107 (56.6 %) tested positive for P. aeruginosa (75.7 %), Salmonella spp. (10.3 %), or for both Salmonella spp. and P. aeruginosa (14 %). A logistic regression model shows that the probability of potable groundwater depends on both season and aquifer type. Typically, water samples were more likely to be potable in autumn-winter than in spring-summer periods (odds ratio, OR = 2.1; 95 % confidence interval, 95 % CI = 1.6–2.7) and from karst-fissured rather than porous aquifers (OR = 5.8; 95 % CI = 4.4–7.8). Optional parameters only showed a seasonal pattern (OR = 2.6; 95 % CI = 1.7–3.9). Clearly, further investigation of groundwater microbiological aspects should be carried out to identify the risks of fecal contamination and to establish appropriate protection methods, which take into account the hydrogeological and climatic characteristics of this region.

Using Cilioplankton as an Indicator of the Ecological Condition of Aquatic Ecosystems

“…Logical regression is a popular statistical method used in biology and ecology [27][28][29]. It is a standard analysis method in situations where the dependent variable (Y) is dichotomous, taking the values 0 and 1.…”

Groundwater quality assessment and characterization of shallow basement aquifers in parts of ado ekiti metropolis, Southwestern Nigeria

“…Several methods have then been adopted in the evaluation of groundwater pollution. Hydrochemistry has become one of the tools in the evaluation of water suitability for different purposes such as industrial, domestic and agricultural purposes [7][8][9][10][11][12][13][14]16]. This is due to the ability of water in dissolving anything (minerals, rocks and solids), and it comes in contact with.…”

“…This is due to the ability of water in dissolving anything (minerals, rocks and solids), and it comes in contact with. Hydrochemistry in groundwater quality evaluation is limited in the overall water quality studies, but the combination of hydrochemistry and bacteriological approach has been adjudged as a comprehensive way of assessing water quality of any area [14]. These hydrogeochemical processes have aided the contamination of aquifers through the introduction of microorganisms such as P. aeruginosa, Salmonella spp., and E. coli [15].…”

“…These hydrogeochemical processes have aided the contamination of aquifers through the introduction of microorganisms such as P. aeruginosa, Salmonella spp., and E. coli [15]. The movement of these microorganisms into aquifers depends on the microorganisms, permeabilities of aquifer materials, proximity to sewage facilities and many more [14,15]. The invasion of these organisms in urban areas is traceable to several processes such as uncontrolled sewage, grazing and manure spreading with attendant outbreak of waterborne diseases [13,14,17,18].…”

“…The movement of these microorganisms into aquifers depends on the microorganisms, permeabilities of aquifer materials, proximity to sewage facilities and many more [14,15]. The invasion of these organisms in urban areas is traceable to several processes such as uncontrolled sewage, grazing and manure spreading with attendant outbreak of waterborne diseases [13,14,17,18]. Geographical information system (GIS) has also emerged as another tool employed in developing solutions to several water problems, assessing water quality and managing water resources on a local or regional scale [19][20][21][22].…”