Spatial decision support system for assessing lake pollution hazard: southeastern pampean shallow lakes (Argentina) as a case study

Abstract

This study gives an account of the implementation of a decision support system as a logical framework for assessing lake pollution hazard. The use of this system is demonstrated with an example from two lake watersheds, each one with different land-use, soil and topographic characteristics and also management regulations for natural resource protection. Lake pollution hazard is assessed as a function of two primary topics: hydrologic and soil conditions. This model shows the state of each evaluated subwatershed with respect to its potential contribution to lake pollution hazard based mainly on easily measurable and commonly used parameters: drainage density, hydraulic gradient, water table depth, soil media, landcover and topography. Mapped outputs from the logic model allowed the identification of several subwatersheds in each lake system as the main water resource protection areas. La Brava Lake Watershed results reasonably fit the natural conditions of the watershed, identifying those subwatersheds with a moderate to high drainage density, high hydraulic gradient and extensive agricultural activities. Regarding Los Padres Lake Watershed, moderate to high drainage density, a high to a very high hydraulic gradient, shallow water depth, silt-loam soil texture and intensive agricultural and residential lands, contributed to a high lake pollution hazard. Results highlighted differences between both freshwater systems, being Los Padres Lake Watershed a more vulnerable ecosystem, requiring decision maker's intervention based on accurate and up-to-date information.

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

“…As mentioned earlier, over the last years, La Brava and Los Padres lakes have been impacted by human disturbances, derived from agricultural and recreational activities, urbanization and waste increase from different origins (Romanelli et al, 2014). Several studies have confirmed the anthropogenic impact on the two lakes, showing the presence of diverse pollutants (heavy metals, pesticides and herbicides) in water, soil, aquatic macrophytes, and fauna (Miglioranza et al, 1998(Miglioranza et al, , 2004Romanelli et al, 2014).…”

A biological and nitrate isotopic assessment framework to understand eutrophication in aquatic ecosystems

“…In a 2.5 km-radius buffer from each lake, Romanelli et al, 2013 identified the dominance of agricultural activities in La Brava Lake (63.65 %), horticulture in Los Padres Lake (63.88 %; Horticultural Belt of Mar del Plata City with greenhouse and open-field cropping systems) and pastures with livestock in Nahuel Rucá Lake (44.15 %). Moreover, close to Los Padres and La Brava lakes there are two permanent villages (Los Padres and La Brava) with 1,672 and 115 permanent residents, respectively (INDEC, 2012), and many tourism-related facilities along their shores (Romanelli et al, 2014b). Nahuel Rucá Lake is located within two private farmlands with cattle-breeding as the dominant economic activity.…”

“…Groundwater is a significant water source to these three lakes, directly discharging into the lake bed and indirectly via the gaining inflow streams. In addition, in the case of La Brava Lake, it also receives a water contribution from the fissure system present in La Brava Range (western margin of the lake) (Romanelli et al, 2014b).…”

Fish-trematode systems as indicators of anthropogenic disturbance: Effects of urbanization on a small stream

“…The creek has a length of 30 km, and before its outfall it passes through horticultural areas and an urban zone along the north side of Mar del Plata city (Miglioranza et al, 2004). Both the lake and the creek are embedded in an intensive horticultural agroecosystem (Miglioranza et al, 2004;Romanelli et al, 2014). On the other hand, along its urban portion, the creek receives the discharge of drain storms, draining large areas of the city.…”

“…Both Los Padres lake and the headwaters of La Tapera creek receive diverse pollutants from surrounding horticultural areas (Miglioranza et al, 2004;Romanelli et al, 2014), therefore a differential detrimental effect on parasites at urban sections should imply the input of other compounds. La Tapera stream is not connected with official sewage dumps, however, Isla et al (1998) reported high concentrations of faecal coliforms attributed to domestic residential inputs which could be sources for other kinds of chemicals.…”