GIS-based pollution hazard mapping and assessment framework of shallow lakes: southeastern Pampean lakes (Argentina) as a case study

Abstract

The assessment of water vulnerability and pollution hazard traditionally places particular emphasis on the study on groundwaters more than on surface waters. Consequently, a GIS-based Lake Pollution Hazard Index (LPHI) was proposed for assessing and mapping the potential pollution hazard for shallow lakes due to the interaction between the Potential Pollutant Load and the Lake Vulnerability. It includes easily measurable and commonly used parameters: land cover, terrain slope and direction, and soil media. Three shallow lake ecosystems of the southeastern Pampa Plain (Argentina) were chosen to test the usefulness and applicability of this suggested index. Moreover, anthropogenic and natural medium influence on biophysical parameters in these three ecosystems was examined. The evaluation of the LPHI map shows for La Brava and Los Padres lakes the highest pollution hazard (≈30 % with high to very high category) while Nahuel Rucá Lake seems to be the less hazardous water body (just 9.33 % with high LPHI). The increase in LPHI value is attributed to a different loading of pollutants governed by land cover category and/or the exposure to high slopes and influence of slope direction. Dissolved oxygen and biochemical oxygen demand values indicate a moderately polluted and eutrophized condition of shallow lake waters, mainly related to moderate agricultural activities and/or cattle production. Obtained information by means of LPHI calculation result useful to perform a local diagnosis of the potential pollution hazard to a freshwater ecosystem in order to implement basic guidelines to improve lake sustainability.

Temporal variations of larval digenean assemblages parasitizing Heleobia parchappii (Mollusca: Cochliopidae) in two shallow lakes from the Buenos Aires province, Argentina

“…1). These lakes are characterized by different surface areas and by different values of maximum depth (4 km 2 ; 4 m, and 2.16 km 2 ; 2.1 m, respectively) and by being naturally euthropic (Romanelli et al, 2013).…”

Evaluation of the quality of lentic ecosystems in Romania by a GIS based WRASTIC model

“…For example, Mirzaei et al 19 calculated WRASTIC index for assessment of pollution risk, respectively degradation sources, from the watershed that feeds a water body. Potential pollutant load index (PPL) was employed by Romanelli et al 18 for analyzing the presence and intensity of potential pollution sources from the drainage area of several lakes, with the purpose of establishing degradation classes of the water body. In the same study, the Lake Vulnerability Index highlighted the capacity of the water body to handle the impact generated by degradation sources, taking into account parameters like slope, soil permeability or aspect of slopes 18 .…”

“…www.nature.com/scientificreports/ WRASTIC-HI index was developed by using three indicators ( Supplementary Fig. 1), as follows: Potential Pollutant Load (PPL) 18 , Wastewater-Recreational-Agricultural-Size-Transportations-Industrial-Cover-Pollutant Load (WRASTIC) 51 and Lake Vulnerability (LV) 18 . PPL and WRASTIC use information regarding the categories of land use within the basins of the lakes analyzed, identified as possible sources of degradation.…”

“…WRASTIC-HI was defined by the following components: Wastewater discharge (W), Recreational land use impacts (R), Agricultural land use impacts (A), Size of watershed (S), Transportation ways (T), Industrial land use impacts (I), The amount of vegetative ground Cover (C), Hazard Index (HI), which distinguishes Permeability (P), Exposition (E) and Slope (S) ( Supplementary Tables 3, 4) 18,19 .…”

“…The lentic ecosystems were classified in three categories as follows: degraded, semi-degraded and natural lentic ecosystems. In the second stage, relevant indicators, previously identified as determinants for assessment of environmental degradation in a multifactorial analysis 1,18,19 , were calculated. Finally, a correlation between the calculated indicators and the degradation state of lentic ecosystems was done.…”