Defining Nutrient and Biochemical Oxygen Demand Baselines for Tropical Rivers and Streams in São Paulo State (Brazil): A Comparison Between Reference and Impacted Sites (original) (raw)
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Environmental Monitoring and Assessment, 2014
The aquatic systems responsible for water supply in the Brazilian Federal District (FD) have been threatened by anthropogenic pressures, especially considering the expressive demographic increase in the region during the last decades. The purposes of this research were: (a) to assess the water quality in streams located in the FD by monitoring physical-chemical variables; (b) to define baselines for these variables among different ecological status categories. The 14 ) seasons. All sampling sites were classified in four categories ("very impacted", "impacted", "in transition" and "natural") using an adaptation of a rapid habitat assessment protocol.
This study aimed to evaluate, comparatively, the influence of distinct environmental impacts in the watershed on the rivers Capivara, Lavapés, Araquá and Pardo and the transference of effects downstream. Methods: The limnological/water quality study was carried out in rainy (March/2007) and dry (September/2007) seasons, considering 17 sampling stations. Results: Variables such as channel width and depth, water velocity and temperature increased towards the river’s mouth; water transparency, velocity and dissolved oxygen were higher in the upstream regions. Light penetration was total at most sampling stations and pH was predominantly acid. The sampling stations impacted by pollution sources, Lavapés and Araquá Rivers, exhibited higher values of electric conductivity, suspended solids, total nitrogen, nitrate, nitrite, ammonium, total dissolved phosphorus, BOD, and thermotolerant coliforms. Higher values of electric conductivity, turbidity and suspended solids were observed in the rainy season, whereas higher chlorophyll concentrations occurred in the dry season. The Lavapés River exhibits the worst environmental condition, while Capivara River is under better state of conservation. This study shows that it is urgent the implementation of measures for preservation and restoration of these regional aquatic ecosystems. All studied rivers were influenced by seasonal variation, sewage discharges and by watershed use and occupation. The TSI is a good analysis tool. The studied rivers export organic matter and TN, TP and SS loads to Tietê and Paranapanema rivers. Conclusions: This study show the importance of river management and that the accelerated degradation of the river systems indicates the little progress of the Brazilian legislation in terms of preservation and good management practices and that the interface between science, law, management and conservation need to be improved. Keywords: pollution, CONAMA 357, trophic state index, loads.
River Research and Applications, 2008
Time series of dissolved oxygen (DO), biochemical oxygen demand (BOD), nitrate, total phosphorus, chloride, ammonia and faecal coliforms (FC), monitored by CETESB ('Companhia de Tecnologia de Saneamento Ambiental'), in the period from 1979 to 2001, were analysed in seven river basins located in the São Paulo State, one of the most developed regions in Brazil. The selected rivers, Piracicaba, Mogi-Guaçu, Turvo Grande, Peixe, Aguapeí, São José dos Dourados and Alto Paranapanema have different degrees of development concerning industrial, agricultural and population growth. Trend analysis methodology was based on graphical exploratory analysis followed by confirmation through statistical tests. Results showed impoverishment of the water quality conditions in most of the studied basins, represented by the positive trends of the parameters (BOD, nitrogens, total phosphorus, clorate and FC) and negative trend of the parameter (DO). Among the analysed basins, the Piracicaba River is the most severely affected with higher variations in the magnitude followed by the basins of the Mogi-Guaçu, Turvo Grande, Peixe and Aguapeí Rivers. On the other hand, the Alto Paranapanema and São José dos Dourados basins are the least affected.
Land uses, Nitrogen and Phosphorus estimated fluxes in a Brazilian semi-arid watershed
Journal of Arid Environments, 2019
This paper presents the estimates of nitrogen and phosphorus loads associated with different land uses in a semiarid watershed in the Brazilian northeast (NE). To calculate the annual loads and calibrate de estimates, we used emission factors related to natural processes and human activities from land uses and monitored the nutrient concentrations in surficial waters. The concentrations of TN were above the 2.18 mg N L −1 limit for lotic environments while the TP exceeded the limit value of 0.15 mg P L −1 established in the Brazilian legislation. The total loads L e N P , corresponded to 16,621 t N yr −1 and 3,211 t P yr −1 or 1,292 t N km −2 yr −1 and 250 t P km −2 yr −1. The anthropogenic emissions accounted for 82.1% of the N and 91.3% of the P emitted. The results for the Salgado river basin are lower than those estimated globally, but exceed the values obtained for the South American continent in an order of magnitude. The use of nutrient loads instead of concentrations, particularly in areas where detailed studies on nutrient concentrations are unavailable, such as in the semi-arid NE Brazil, may become a satisfactory approach to evaluate the sensitivity of aquatic systems to a further introduction of anthropogenic effluents.
Hydrologic Monitoring Plan of the Brazilian Water Producer/PCJ Project
Journal of Environmental Protection, 2016
Both Ecosystem-based Adaptation (EbA) and Payment for Ecosystem Services (PES) have a wide range of strategies that include different economic instruments for nature conservation. Although the generation and maintenance of payment for hydrologic ecosystem services (Water-PES) is expanding in Brazil, there are difficulties in the implementation of projects. Due to the complexity and non-linearity of the hydrological processes, also affecting both EbA and Water-PES goals, monitoring qualiquantitative aspects of streams have been here addressed as a useful management tool. This study presents the Hydrological Monitoring Plan (HMP) of the Water Producer/PCJ project, operating between 2009-2014, in order to: 1) evaluate the impact of project actions under water quali-quantitative aspects; and 2) promote the incorporation of HMP's elements in water resources management. HMP of the Water Producer/PCJ project has been implemented following the conditions for efficiency (baseline, long-term scale compatible with the actions of the project, in the experimental and reference watersheds). In addition, HMP is being implemented from upstream to downstream in catchments with areas ranging from 17 to 130 km 2. This proposal favors the quantification and valuation of hydrologic services that could be assessed by ecohydrologic monitoring and modeling. Thus, we look forward to the consolidation of the Brazilian information system of water resources, the reduction of modeling uncertainties and integrated assessment of the consequences of landuse/land-cover change that strongly impact goals of EbA and Water-PES initiatives.
Spatiotemporal analysis of water quality indicators in a watershed in Brazilian Cerrado
Water Supply
Tools for monitoring and evaluating water quality are necessary for the measurement of environmental impacts arising from diverse activities in hydrographic basins. Here, the water quality of the Verdinho River, an important hydrographic basin of Brazilian Cerrado, was evaluated using 16 physical–chemical parameters. The indicators with major interference with water quality were identified by principal component analysis (PCA), in order to suggest less laborious and less expensive assessments. The water quality index (WQI) was applied considering seasonal changes and the analysis of eutrophication potential was determined using the trophic state index (TSI). The concentrations of chemical water quality indicators (e.g., nitrate, total phosphorus, total nitrogen) increased mainly in the rainy season. The PCA explained 73.69% of the variance among the data. Total solids, temperature, turbidity, alkalinity, biochemical oxygen demand, hardness, total phosphorus, nitrite, nitrate and amm...
Environmental Analysis of the Queixada Stream Watershed In Jataí-Goiás (Brazil
IJASS JOURNAL, 2023
The present work consists of a scientific investigation that addresses the study of the Queixada Stream watershed, located in the municipality of Jataí, southwest of the state of Goiás, Brazil. The main objective is to analyze the water quality and environmental vulnerability of this watershed. Land use and occupation are essential elements for evaluating and understanding the physical characteristics of the environment. Urban expansion in Jataí has negatively impacted areas of natural vegetation and water sources, and the study area of the Queixada Stream watershed is no exception. This expansion is associated with population growth, resulting in increased demand and expectations for socioeconomic development, which in turn implies greater consumption of natural resources. The overall objective of this study is to conduct a comprehensive environmental analysis of the Queixada Stream watershed in the municipality of Jataí, Goiás. In addition, the water and soil quality will be evaluated, using resolutions 357/2005 and 420/2009 from the National Council for the Environment (CONAMA) as parameters. These resolutions establish guidelines and criteria for monitoring and controlling environmental quality. To achieve the proposed objectives, two methods were used in this study: field research with sample collection and laboratory analysis of water and soil. These elements are naturally found in the waters and are responsible for the proper functioning of aquatic ecosystems.
Evaluation of physicochemical water parameters in watersheds of southern Brazil
2020
Water-quality monitoring is one of the main instruments for water-resource management. This work therefore evaluated the water quality of the contribution basin of the Sinnott water treatment plant as well as the relationship between physicochemical water parameters, and analyzed the seasonal variation of water quality parameters as a function of rainfall. The study area encompassed the contribution basin of the Sinnott water treatment plant, formed mainly by the drainage areas of the Pelotas stream and its tributary, the Quilombo Stream, located in the city of Pelotas-Rio Grande do Sul, Brazil. A set of 118,368 data points for each stream was analyzed between 2007 and 2012. The following water quality parameters were evaluated: turbidity, temperature, color, pH, hardness, dissolved oxygen, organic matter, and alkalinity. Results showed that dissolved oxygen and water pH values conformed with Brazilian legislation in the 6 years evaluated. However, water color was the parameter that remained the greatest number of days above the set limits, mainly in the Pelotas Stream. Result indicates the need for conservation actions in the catchment, especially considering the importance of color for the assessment of water quality for public supply, in terms of both treatment costs and of public health. Highest values for water color, turbidity, and organic matter coincided with the occurrence of the highest rainfall values. Agricultural activities may potentiate sedimentation in the contribution basin of the Sinnott water treatment plant.
Ecological Questions, 2008
The Water Code, created in 1934, was the first attempt of governmental intervention in Water Basin Management in Brazil. It was a centralized bureaucratic system established to regulate the use of water. Since the beginning, Water Management suffered significant changes and the model currently used is an integrated participative systemic model. The distribution of water resources in Brazil is very irregular, 70% of water is located in the North region, 15% to the Central-West, 12% in the South and Southeast and 3% in the Northeast region (BNDES 1997). The state of São Paulo is located in the Southeast region, which has the biggest water consumption. The Water Resources Agency of São Paulo State (CETESB) has an advanced water management system with 20 Watershed Management Committees. Groups from different social sectors compose these committees. They constitute a new kind of organization that is responsible for the watershed planning. Actually, these committees use to obtain relevant information but they are not able to develop future scenarios, objectives, strategies and temporary goals for the water basin. The Mogi-Guaçu watershed is the most important basin in São Paulo State from the economic point of view, but the river has problems of erosion, silting, flooding and low water quality. The water quality problems are due to nonpoint sources of pollution from agriculture and municipal and industrial point sources.