Fluvial Hydrogeochemistry in a Sub-Tropical Coastal Watershed in Brazil

Changes in landscape patterns in a river basin play a crucial role in the change on load of non-point source pollution. The spatial distribution of various land use types affects the transmission of non-point source pollutants on the basis of source-sink theory in landscape ecology. Jiulong River basin in southeast of China was selected as the study area in this paper. Aiming to analyze the correlation between changing landscape patterns and load of non-point source pollution in this area, traditional landscape metrics and the improved location-weighted landscape contrast index based on the minimum hydrological response unit (HRULCI) were applied in this study, in combination with remote sensing and geographic information system (GIS) technique. The results of the landscape metrics showed the enhanced fragmentation extent and the decreasing polymerization degree of the overall landscape in the watershed. High values of HRULCI were concentrated in cultivated land, while low HRULCI values mostly appeared in forestland, indicating that cultivated land substantially enhanced non-point source pollution, while forestland inhibited the pollution process.

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Managed aquifer recharge: study of undisturbed soil column tests on the infiltration and treatment capacity using effluent of wastewater stabilization pond

RBRH ◽

10.1590/2318-0331.231820180060 ◽

2018 ◽

Vol 23 (0) ◽

Author(s):

Jaqueline Vígolo Coutinho ◽

Cristiano das Neves Almeida ◽

Eduardo Bernardo da Silva ◽

Catalin Stefan ◽

Gilson Barbosa Athayde Júnior ◽

...

Keyword(s):

Soil Column ◽

Managed Aquifer Recharge ◽

Future Research ◽

Sewage Effluent ◽

Ammoniacal Nitrogen ◽

Aquifer Recharge ◽

Soil Columns ◽

Undisturbed Soil ◽

Coastal Watershed ◽

Stabilization Pond

ABSTRACT Managed Aquifer Recharge (MAR) is a useful tool for the treatment and use of sewage effluent because it complements conventional treatment, recovers the aquifer and minimizes risk of saltwater intrusion. This study aims to investigate technical data to determine the treatment of wastewater stabilization pond effluent using undisturbed soil columns collected from a coastal watershed study area within the BRAMAR (BRAzil Managed Aquifer Recharge) project. The treatment efficiency was monitored by measuring physico-chemical parameters (BOD 5, COD, DOC, TSS, NH3 and NO3) in two columns filled with undisturbed sandy soil in which sewage effluent was infiltrated under unsaturated condition for 72 days with an average input flow of 10 mm h-1. Results indicated reduction greater than 60% of organic matter, suspended solids and ammoniacal nitrogen. However, high concentrations of nitrate in the outflow were detected originating from nitrification of ammoniacal nitrogen. Moreover, difficulties in relation to soil clogging were observed. Furthermore, this study brought relevant contributions to understanding the influence of the infiltration rate and ability to treat effluent from wastewater stabilization ponds using undisturbed soil columns. Future research should be undertaken to improve the pretreatment methods and the operation of a MAR system in the study area.

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Application of ecological indicators in coastal watershed under high pressure during summer period

RBRH ◽

10.1590/2318-0331.011615106 ◽

2016 ◽

Vol 21 (3) ◽

pp. 537-548 ◽

Cited By ~ 4

Author(s):

Aichely Rodrigues da Silva ◽

Alessandra Larissa D’ Oliveira Fonseca ◽

Claudinei José Rodrigues ◽

Ângela da Veiga Beltrame

Keyword(s):

Water Quality ◽

Environmental Quality ◽

Rapid Assessment ◽

Population Increase ◽

Summer Period ◽

Coastal Watershed ◽

Assessment Protocol ◽

The North ◽

Trophic Index ◽

Median Area

ABSTRACT Water bodies located in coastal areas are subject to human pressures and the loss of environmental quality. The objective of this study was to evaluate the environmental quality of the river Papaquara through water quality and river landscape, using the Trophic Index (TRIX) and Rapid Assessment Protocol (RAP). The study was developed in the watershed located in the north of the island of Santa Catarina, Florianópolis – SC, whose population increase in the summer is around 280%. The Trophic Index and the Rapid Assessment Protocol were evaluated in the pre-summer period, summer and after-summer in seven sample points along the inner areas (higher population density), median and outside the Papaquara river, plus two points in affluent. The river Papaquara showed up in great stress state, is classified as eutrophic, 77% of the samples and changed in 50% of the sampled area, as the TRIX index and RAP, respectively. The internal area registered up eutrophic and impacted in all periods analyzed. The median area and the outer decreased their water quality, due to summer activity, while there was no change in environmental quality by RAP. A significant correlation between the indices used indicated that the RAP should be used with caution to describe the condition of water quality. This analysis has submitted be more appropriate when used in river scale as a whole, but not isolated segments.

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