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Increased droughts and variable rainfall patterns may alter the capacity to provide ecosystem services, such as biomass production and clean water provision. The impact of these factors in a semi-arid region, especially on a dry tropical forest with Vertisols and under different land uses such as regenerated vegetation and thinned vegetation, is still unclear. This study analyzes hydrologic processes under precipitation pulses and intra-seasonal droughts, and suggests management practices for ecosystem services improvement. A local 43-year dataset showed a varying climate with a decrease in number of small events, and an increase in the number of dry days and in event rainfall intensity, in two catchments with different land use patterns and with Vertisols, a major soil order in semi-arid tropics. The onset of runoff depends on the expansive characteristics of the soil rather than land use, as dry spells promote micro-cracks that delay the runoff process. Forest thinning enhances groundcover development and is a better management practice for biomass production. This management practice shows a lower water yield when compared to a regenerated forest, supporting the decision of investing in forest regeneration in order to attend to an increasing water storage demand.
Maria Guerreiro; Eunice Maia de Andrade; Helba Palácio; José Brasil; Jacques Ribeiro Filho. Enhancing Ecosystem Services to Minimize Impact of Climate Variability in a Dry Tropical Forest with Vertisols. Hydrology 2021, 8, 46 .
AMA StyleMaria Guerreiro, Eunice Maia de Andrade, Helba Palácio, José Brasil, Jacques Ribeiro Filho. Enhancing Ecosystem Services to Minimize Impact of Climate Variability in a Dry Tropical Forest with Vertisols. Hydrology. 2021; 8 (1):46.
Chicago/Turabian StyleMaria Guerreiro; Eunice Maia de Andrade; Helba Palácio; José Brasil; Jacques Ribeiro Filho. 2021. "Enhancing Ecosystem Services to Minimize Impact of Climate Variability in a Dry Tropical Forest with Vertisols." Hydrology 8, no. 1: 46.
Monitoring water quality in urban stream is of utmost importance for water resources managers, who are pressured to optimize monitoring schemes in order to reduce costs. The present study aims to use the results of a 2-year-long water quality monitoring program of an urban stream in Portugal to identify improvement opportunities. The urban stream under study was subjected to wastewater treatment plants effluent discharges, leachates from a major sealed landfill, low-class housing effluents, and nonpoint sources of pollution. Contributing watersheds are mostly artificial surfaces and agricultural land, which irrigate directly from the river. River water quality was evaluated on 11 sampling locations for 24 months from October 2013 to September 2015. The present paper describes statistical analysis of the results obtained for 12 physicochemical parameters in order to optimize the monitoring scheme. Cluster analysis detected a seasonal variation in the water quality and a spatial pattern based on the major point sources of pollution. A factor analysis showed that the parameters that mostly contribute to water quality assessment in this urban river are alkalinity, ammonia, electrical conductivity, pH, temperature, and dissolved oxygen. Results suggest that the monitoring efforts—and associated costs—may be reduced by decreasing monitoring frequency, sampling points, and monitored parameters. The statistical analysis described in this study may be replicated in other water quality monitoring programs, providing useful and important information for the systematic and iterative assessment of the adequacy of water quality sampling programs towards a sustainable management of water quality surveillance.
Maria Simas Guerreiro; Isabel Maria Abreu; Álvaro Monteiro; Teresa Jesus; Ana Fonseca. Considerations on the monitoring of water quality in urban streams: a case study in Portugal. Environmental Monitoring and Assessment 2020, 192, 1 -11.
AMA StyleMaria Simas Guerreiro, Isabel Maria Abreu, Álvaro Monteiro, Teresa Jesus, Ana Fonseca. Considerations on the monitoring of water quality in urban streams: a case study in Portugal. Environmental Monitoring and Assessment. 2020; 192 (6):1-11.
Chicago/Turabian StyleMaria Simas Guerreiro; Isabel Maria Abreu; Álvaro Monteiro; Teresa Jesus; Ana Fonseca. 2020. "Considerations on the monitoring of water quality in urban streams: a case study in Portugal." Environmental Monitoring and Assessment 192, no. 6: 1-11.
Eunice Maia Andrade; Maria João Simas Guerreiro; Helba Araújo Queiroz Palácio; Diego Antunes Campos. Ecohydrology in a Brazilian tropical dry forest: thinned vegetation impact on hydrological functions and ecosystem services. Journal of Hydrology: Regional Studies 2020, 27, 1 .
AMA StyleEunice Maia Andrade, Maria João Simas Guerreiro, Helba Araújo Queiroz Palácio, Diego Antunes Campos. Ecohydrology in a Brazilian tropical dry forest: thinned vegetation impact on hydrological functions and ecosystem services. Journal of Hydrology: Regional Studies. 2020; 27 ():1.
Chicago/Turabian StyleEunice Maia Andrade; Maria João Simas Guerreiro; Helba Araújo Queiroz Palácio; Diego Antunes Campos. 2020. "Ecohydrology in a Brazilian tropical dry forest: thinned vegetation impact on hydrological functions and ecosystem services." Journal of Hydrology: Regional Studies 27, no. : 1.
Adequate management of indoor air quality (IAQ) in healthcare units has relevant impacts on sustainability performance due to its effects on patient safety, occupational health and safety, and energy consumptions. This study sought to identify improvement opportunities on IAQ management by collecting and analyzing experimental data of selected parameters in three healthcare units in Portugal: Two general hospitals and one primary healthcare center. Indoor air temperature, relative humidity, CO2, bacteria, and fungi concentrations were measured in summer and winter campaigns in June/July 2017 and in January/March 2018. Results show that the exclusive use of natural ventilation is not adequate when the affluence of users is high, but the analyzed parameters revealed acceptable results under low occupation intensity conditions. Results also show that keeping low indoor air relative humidity has a significant impact in reducing fungi concentration and that there is a significant correlation at the 0.05 level between indoor air CO2 concentration and bacterial loads. Therefore, as opportunities to improve sustainability, IAQ management in healthcare facilities should consider natural ventilation as a complement to mechanical ventilation systems and should focus on adequate control of indoor air relative humidity and CO2 concentration to reduce the risk of airborne infections.
Ana Fonseca; Isabel Abreu; Maria João Guerreiro; Cristina Abreu; Ricardo Silva; Nelson Barros. Indoor Air Quality and Sustainability Management—Case Study in Three Portuguese Healthcare Units. Sustainability 2018, 11, 101 .
AMA StyleAna Fonseca, Isabel Abreu, Maria João Guerreiro, Cristina Abreu, Ricardo Silva, Nelson Barros. Indoor Air Quality and Sustainability Management—Case Study in Three Portuguese Healthcare Units. Sustainability. 2018; 11 (1):101.
Chicago/Turabian StyleAna Fonseca; Isabel Abreu; Maria João Guerreiro; Cristina Abreu; Ricardo Silva; Nelson Barros. 2018. "Indoor Air Quality and Sustainability Management—Case Study in Three Portuguese Healthcare Units." Sustainability 11, no. 1: 101.
This research studies the carbonation phenomenon of cement due to the reaction of its components with water. In this chemical reaction occurs the formation of calcium carbonate and the absorption of CO2 in the atmosphere, which contributes to the reduction of the Greenhouse Effect. However, carbonation also causes pathologies such as efflorescence, staining and corrosion of steel in concrete. This research shows the results of experiments with specimens of concrete permeable, made with cement and big aggregates (calcareous stone) in the ratio of 1: 4.4 (cement: stone) and a factor of 0.3 for water / cement. The specimens were kept in contact with water containing different amounts of CO2 - distilled, ionized alkaline, carbonated, and tap water. After the experiments were carried out, an increase in pH, a mean compressive strength of 12.3 MPa and a permeability rate of 1.28 l / h was observed. The results show that the permeable concrete did not present any pathologies resulting from the carbonation during the period of the research, which recommended the same for use in road pavements.
Evailton Arantes De Oliveira; Maria P. S. Lamêgo Oliveira; Arlene M. L. Da Silva Campos; Murilo Ferreira Dos Santos; Jessica A. Afonso Souza; Maria Correia De S. Guerreiro; Maria Alzira Pimenta Dinis. Environmental Implications of pH in a Pervious Concrete Pavement on Highway BR-319, Amazonas, Brazil. Current World Environment 2018, 13, 187 -193.
AMA StyleEvailton Arantes De Oliveira, Maria P. S. Lamêgo Oliveira, Arlene M. L. Da Silva Campos, Murilo Ferreira Dos Santos, Jessica A. Afonso Souza, Maria Correia De S. Guerreiro, Maria Alzira Pimenta Dinis. Environmental Implications of pH in a Pervious Concrete Pavement on Highway BR-319, Amazonas, Brazil. Current World Environment. 2018; 13 (2):187-193.
Chicago/Turabian StyleEvailton Arantes De Oliveira; Maria P. S. Lamêgo Oliveira; Arlene M. L. Da Silva Campos; Murilo Ferreira Dos Santos; Jessica A. Afonso Souza; Maria Correia De S. Guerreiro; Maria Alzira Pimenta Dinis. 2018. "Environmental Implications of pH in a Pervious Concrete Pavement on Highway BR-319, Amazonas, Brazil." Current World Environment 13, no. 2: 187-193.
Dry tropical forests account for over 1,000,000 km2, and there is still lack of knowledge on their hydrologic processes. The curve number (CN) hydrologic model developed by the Natural Resources Conservation Service (NRCS) is widely applied for runoff determination in various parts of the world, but not so in tropical semiarid regions. This study analyzes the impact of land use changes on the CN model in a tropical semiarid environment, in two catchments of native dry tropical forest and thinned dry tropical forest land use from 2009 to 2012. The CN model was calibrated and validated for the NRCS recommended initial abstraction ratio λ = 0.2, and for λ evaluated from rainfall and runoff data. A reliability analysis was performed using Monte Carlo simulation. Model goodness-of-fit was assessed with statistical criteria. A total of 42 and 40 rainfall-runoff events were analyzed for the native and thinned dry tropical forest, respectively. Characteristic λ values of 0.15 and 0.11 were determined for the two respective catchments. Although CN values were similar for both land uses, CNλ=0.20 = 80 and CNmedian λ = 77, the thinned catchment showed a higher CN model parameters variability. The CN model was more sensitive to variations of CN values than to those of λ. This study showed that no matter the vegetation management in a dry tropical forest environment, modeled runoff is not affected by λ, but rather affected by CN, which represents soil, landuse and management.
E. M Andrade; J. R Araújo Neto; M. J. S Guerreiro; J. C. N Santos; H. A. Q Palácio. Land Use Effect on the CN Model Parameters in a Tropical Dry Environment. Water Resources Management 2017, 31, 4103 -4116.
AMA StyleE. M Andrade, J. R Araújo Neto, M. J. S Guerreiro, J. C. N Santos, H. A. Q Palácio. Land Use Effect on the CN Model Parameters in a Tropical Dry Environment. Water Resources Management. 2017; 31 (13):4103-4116.
Chicago/Turabian StyleE. M Andrade; J. R Araújo Neto; M. J. S Guerreiro; J. C. N Santos; H. A. Q Palácio. 2017. "Land Use Effect on the CN Model Parameters in a Tropical Dry Environment." Water Resources Management 31, no. 13: 4103-4116.
Júlio César Neves Dos Santos; Eunice Maia De Andrade; Pedro Henrique Augusto Medeiros; Maria João Simas Guerreiro; Helba Araujo De Queiroz Palácio. Land use impact on soil erosion at different scales in the Brazilian semi-arid. REVISTA CIÊNCIA AGRONÔMICA 2017, 48, 1 .
AMA StyleJúlio César Neves Dos Santos, Eunice Maia De Andrade, Pedro Henrique Augusto Medeiros, Maria João Simas Guerreiro, Helba Araujo De Queiroz Palácio. Land use impact on soil erosion at different scales in the Brazilian semi-arid. REVISTA CIÊNCIA AGRONÔMICA. 2017; 48 (2):1.
Chicago/Turabian StyleJúlio César Neves Dos Santos; Eunice Maia De Andrade; Pedro Henrique Augusto Medeiros; Maria João Simas Guerreiro; Helba Araujo De Queiroz Palácio. 2017. "Land use impact on soil erosion at different scales in the Brazilian semi-arid." REVISTA CIÊNCIA AGRONÔMICA 48, no. 2: 1.
Rainfall intensity, duration, frequency and magnitude influence both runoff generation and sediment yield. In this study, 176 rainfall events over a five-year period were classified into four regimes based on rainfall depth, duration and 30-minute maximum intensity, using hierarchical cluster analysis in the semiarid region of Brazil. Rainfall Regimes were grouped from higher to lower rainfall depth, longer to shorter duration, and higher to lower I30. Rainfall regime impact on surface runoff and sediment yield was studied in three watersheds under different land use - native tropical dry forest, thinned tropical dry forest, and slash and burn followed by grass cultivation. Thinning of native dry tropical forest reduced surface runoff and sediment yield due to the protective effect of the well-developed herbaceous layer. Runoff generation in the three watersheds showed strong dependence on antecedent soil moisture and the type of rain. Rainfall depth was the major factor for highest sediment yields.
Julio Cesar Neves Dos Santos; Eunice Andrade; Pedro Medeiros; Maria Guerreiro; Helba Araújo De Queiroz Palácio. Effect of Rainfall Characteristics on Runoff and Water Erosion for Different Land Uses in a Tropical Semiarid Region. Water Resources Management 2016, 31, 173 -185.
AMA StyleJulio Cesar Neves Dos Santos, Eunice Andrade, Pedro Medeiros, Maria Guerreiro, Helba Araújo De Queiroz Palácio. Effect of Rainfall Characteristics on Runoff and Water Erosion for Different Land Uses in a Tropical Semiarid Region. Water Resources Management. 2016; 31 (1):173-185.
Chicago/Turabian StyleJulio Cesar Neves Dos Santos; Eunice Andrade; Pedro Medeiros; Maria Guerreiro; Helba Araújo De Queiroz Palácio. 2016. "Effect of Rainfall Characteristics on Runoff and Water Erosion for Different Land Uses in a Tropical Semiarid Region." Water Resources Management 31, no. 1: 173-185.
Soil and water resources effective management and planning in a river basin rely on understanding of runoff generation processes, yield, and their relations to rainfall. This study analyzes the effects of antecedent soil moisture in an expansive soil and the influence of dry spells on soil cracking, runoff generation and yield in a semiarid tropical region in Brazil subject to land use change. Data were collected from 2009 to 2013 in a 2.8 ha watershed, totaling 179 natural rainfall events. In the first year of study (2009), the watershed maintained a typical dry tropical forest cover (arboreal-shrub Caatinga cover). Before the beginning of the second year of study, gamba grass (Andropogon gayanus Kunth) was cultivated after slash and burn of native vegetation. Gamba grass land use was maintained for the rest of the monitoring period. The occurrence of dry spells and the formation of cracks in the Vertisol soil were the most important factors controlling flow generation. Dry spells promoted crack formation in the expansive soil, which acted as preferential flow paths leading to high initial abstractions: average conditions for runoff to be generated included soil moisture content above 20%, rainfall above 70 mm, I30max above 60 mm h-1 and five continuous dry days at the most. The change of vegetation cover in the second year of study did not alter significantly the overall conditions for runoff initiation, showing similar cumulative flow vs. rainfall response, implying that soil conditions, such as humidity and cracks, best explain the flow generation process on the semiarid micro-scale watershed with Vertisol soil.
Julio Cesar Neves dos Santos; Eunice Maia de Andrade; Maria João Simas Guerreiro; Pedro Henrique Augusto Medeiros; Helba Araújo De Queiroz Palácio; José Ribeiro De Araújo Neto. Effect of dry spells and soil cracking on runoff generation in a semiarid micro watershed under land use change. Journal of Hydrology 2016, 541, 1057 -1066.
AMA StyleJulio Cesar Neves dos Santos, Eunice Maia de Andrade, Maria João Simas Guerreiro, Pedro Henrique Augusto Medeiros, Helba Araújo De Queiroz Palácio, José Ribeiro De Araújo Neto. Effect of dry spells and soil cracking on runoff generation in a semiarid micro watershed under land use change. Journal of Hydrology. 2016; 541 ():1057-1066.
Chicago/Turabian StyleJulio Cesar Neves dos Santos; Eunice Maia de Andrade; Maria João Simas Guerreiro; Pedro Henrique Augusto Medeiros; Helba Araújo De Queiroz Palácio; José Ribeiro De Araújo Neto. 2016. "Effect of dry spells and soil cracking on runoff generation in a semiarid micro watershed under land use change." Journal of Hydrology 541, no. : 1057-1066.
Objetivou-se com este estudo gerar um índice de salinidade (ISal) para classificar as águas dos reservatórios no Estado do Ceará, Brasil, empregando-se a técnica multivariada através análise de componentes principais (ACP). Os dados utilizados foram fornecidos pela Companhia de Gestão dos Recursos Hídricos do Ceará e contemplam o período de 1998/2009, com um total de 807 coletas realizadas em 48 reservatórios georeferenciados. Os íons selecionados pela ACP e utilizados na elaboração do ISal foram: Cl-, Na+, Mg+2 e a CE. Foram desenvolvidos mapas que identificam a escala de vulnerabilidade dos reservatórios e correspondentes sub-bacias quanto à salinidade. O íon que apresentou maiores restrições foi o Na+, Objetivou-se com este estudo gerar um índice de salinidade (ISal) para classificar as águas dos reservatórios no Estado do Ceará, Brasil, empregando-se a técnica multivariada através análise de componentes principais (ACP). Os dados utilizados foram fornecidos pela Companhia de Gestão dos Recursos Hídricos do Ceará e contemplam o período de 1998/2009, com um total de 807 coletas realizadas em 48 reservatórios georeferenciados. Os íons selecionados pela ACP e utilizados na elaboração do ISal foram: Cl-, Na+, Mg+2 e a CE. Foram desenvolvidos mapas que identificam a escala de vulnerabilidade dos reservatórios e correspondentes sub-bacias quanto à salinidade. O íon que apresentou maiores restrições foi o Na+, seguido do Mg+2, Cl- e da CE. Os valores do ISal proposto variaram entre 40,6 e 95,3, que classificaram as águas entre moderada a alta restrição de uso. Distinguem-se três zonas geográficas no Estado com moderada a alta restrição quanto à salinidade das águas dos reservatórios. Uma região que apresenta alta restrição ao uso da água superficial de reservatórios para irrigação é composta por parte da bacia Metropolitana e do Médio Jaguaribe, região esta que apresenta maiores restrições em decorrência de altas salinidades. As outras duas regiões apresentam moderada restrição ao uso da água para irrigação, sendo que uma região envolve parte das bacias do Acaraú, Coreaú e Parnaíba e a outra é definida pela bacia do Salgado e parte do Alto Jaguaribe, sendo que as restrições moderadas são em virtude das baixas salinidades.
José Ribeiro De Araújo Neto; Eunice Maia De Andrade; Ana Célia Maia Meireles; Maria Guerreiro; Helba Araújo De Queiroz Palácio. Proposta de índice da salinidade das águas superficiais de reservatórios do Ceará, Brasil. REVISTA [email protected] ON-LINE 2014, 8, 184 -193.
AMA StyleJosé Ribeiro De Araújo Neto, Eunice Maia De Andrade, Ana Célia Maia Meireles, Maria Guerreiro, Helba Araújo De Queiroz Palácio. Proposta de índice da salinidade das águas superficiais de reservatórios do Ceará, Brasil. REVISTA [email protected] ON-LINE. 2014; 8 (2):184-193.
Chicago/Turabian StyleJosé Ribeiro De Araújo Neto; Eunice Maia De Andrade; Ana Célia Maia Meireles; Maria Guerreiro; Helba Araújo De Queiroz Palácio. 2014. "Proposta de índice da salinidade das águas superficiais de reservatórios do Ceará, Brasil." REVISTA [email protected] ON-LINE 8, no. 2: 184-193.
The state of Ceará is a semiarid region in north‐eastern Brazil, having a high spatial and temporal variability of precipitation, which poses challenges for water resources management. The objective of this study is to describe and analyse the long‐term variation of monthly precipitation indices and their relation to sea surface temperature (SST) anomalies. Data from 55 weather stations in the state of Ceará from 1974 to 2009 was analysed. In general, a decreasing tendency in monthly precipitation was observed over almost all the state of Ceará. The results point to a tendency for dry months to become dryer and to a decrease in precipitation intensity. SST anomalies from October to March correlate with precipitation indices from January to April, showing decreasing lag times towards the end of the wet season. The most influential SST anomalies locations are Niño 1+2, Niño 3, Niño 3.4 and Global Tropics.
Maria João Simas Guerreiro; Eunice Andrade; Isabel Abreu; Teresa Lajinha. Long-term variation of precipitation indices in Ceará State, Northeast Brazil. International Journal of Climatology 2013, 33, 2929 -2939.
AMA StyleMaria João Simas Guerreiro, Eunice Andrade, Isabel Abreu, Teresa Lajinha. Long-term variation of precipitation indices in Ceará State, Northeast Brazil. International Journal of Climatology. 2013; 33 (14):2929-2939.
Chicago/Turabian StyleMaria João Simas Guerreiro; Eunice Andrade; Isabel Abreu; Teresa Lajinha. 2013. "Long-term variation of precipitation indices in Ceará State, Northeast Brazil." International Journal of Climatology 33, no. 14: 2929-2939.
Eunice M Andrade; Helba Q Palácio; Julio Cesar N Santos; Maria João S Guerreiro; Joseilson O Rodrigues. Runoff curve number for a small forested watershed in a semiarid region of Brazil. 21st Century Watershed Technology: Improving Water Quality and Environment Conference Proceedings, May 27-June 1, 2012, Bari, Italy 2012, 1 .
AMA StyleEunice M Andrade, Helba Q Palácio, Julio Cesar N Santos, Maria João S Guerreiro, Joseilson O Rodrigues. Runoff curve number for a small forested watershed in a semiarid region of Brazil. 21st Century Watershed Technology: Improving Water Quality and Environment Conference Proceedings, May 27-June 1, 2012, Bari, Italy. 2012; ():1.
Chicago/Turabian StyleEunice M Andrade; Helba Q Palácio; Julio Cesar N Santos; Maria João S Guerreiro; Joseilson O Rodrigues. 2012. "Runoff curve number for a small forested watershed in a semiarid region of Brazil." 21st Century Watershed Technology: Improving Water Quality and Environment Conference Proceedings, May 27-June 1, 2012, Bari, Italy , no. : 1.
Ria Formosa is a large (c.a. 100 km2) mesotidal lagoon system with large intertidal areas and several conflicting uses, such as fisheries, aquaculture, tourism and nature conservation. Its watersheds cover an area of approximately 864 km2, with a perimeter of 166 km and a maximum altitude of 522 m. There are about 100 different land use classes being divided among six major groups: (1) urban, (2) agricultural, (3) forest, (4) rangeland and pastures, (5) wetlands and (6) water bodies. The Soil and Water Assessment Tool (SWAT model) has been applied to the catchment areas in order to simulate water discharges to Ria Formosa, providing forcing to a two-dimensional vertically integrated coupled physical-biogeochemical model, implemented with EcoDynamo—an object oriented modelling software. This model includes water column and sediment processes as well as their interactions and several biological sub-models (e.g. phytoplankton dynamics and bivalve growth). The main objectives of this work are to: (i) Evaluate the relative importance of land drainage, waste water treatment (WTP) plants and water exchanges, across the lagoon inlets, for nutrient dynamics; (ii) Analyse management scenarios related to changes in lagoon bathymetry and their potential effects on system dynamics. Model’ results are being used by the Ria Formosa Natural Park authority for management purposes and may be useful to feedback future updates of the watershed management plans, within the scope of the European Union Water Framework Directive.
Pedro Duarte; B. Azevedo; Maria Guerreiro; C. Ribeiro; R. Bandeira; Antonio Pereira; M. Falcão; Dalila Serpa; J. Reia. Biogeochemical modelling of Ria Formosa (South Portugal). Hydrobiologia 2008, 611, 115 -132.
AMA StylePedro Duarte, B. Azevedo, Maria Guerreiro, C. Ribeiro, R. Bandeira, Antonio Pereira, M. Falcão, Dalila Serpa, J. Reia. Biogeochemical modelling of Ria Formosa (South Portugal). Hydrobiologia. 2008; 611 (1):115-132.
Chicago/Turabian StylePedro Duarte; B. Azevedo; Maria Guerreiro; C. Ribeiro; R. Bandeira; Antonio Pereira; M. Falcão; Dalila Serpa; J. Reia. 2008. "Biogeochemical modelling of Ria Formosa (South Portugal)." Hydrobiologia 611, no. 1: 115-132.
Multivariate statistical techniques, cluster analysis (CA) and factor analysis/principal component analysis (FA/PCA), were applied to analyze the similarities or dissimilarities among the sampling sites to identify spatial and temporal variations in water quality and sources of contamination (natural and anthropogenic). The aquifer under study is supplied by the Trussu River, which has a general direction from west to east, within Iguatu County, Ceará, Brazil. Groundwater samples were collected in four shallow wells, located at the Trussu River alluvial, from October 2002 to February 2004. The samples were analyzed for 13 parameters: pH, electrical conductivity (EC), Na, Ca, Mg, K, Cl, HCO3, PO4, NH4–N, NO3–N, SO4, and sodium adsorption ratio (SAR). Two zones were very well differentiated based on cluster analysis results, and implied a relation to geographic position and time variation. One zone called UL—upland region—corresponds to upland of studied area, used mainly for irrigation and livestock activities. The other zone called DL—downland region—corresponds to the region downstream and is occupied by human settlements. These results may be used to reduce the number of samples analyzed both in space and time, without too much loss of information. Three major independent factors that define water quality in the UL region and four in DL region were identified in the PCA. At both regions, rotated component (RC) loadings identified that the variables responsible for water quality composition are mainly related to soluble salts variables (natural process) and nutrients (high loads of NO3–N, NH4–N), expressing anthropogenic activities. RC also revealed that hydrochemical processes were the major factors responsible for water quality.
Eunice Maia de Andrade; Helba Araújo Queiroz Palácio; Ivam Holanda Souza; Raimundo Alípio De Oliveira Leão; Maria Guerreiro. Land use effects in groundwater composition of an alluvial aquifer (Trussu River, Brazil) by multivariate techniques. Environmental Research 2008, 106, 170 -177.
AMA StyleEunice Maia de Andrade, Helba Araújo Queiroz Palácio, Ivam Holanda Souza, Raimundo Alípio De Oliveira Leão, Maria Guerreiro. Land use effects in groundwater composition of an alluvial aquifer (Trussu River, Brazil) by multivariate techniques. Environmental Research. 2008; 106 (2):170-177.
Chicago/Turabian StyleEunice Maia de Andrade; Helba Araújo Queiroz Palácio; Ivam Holanda Souza; Raimundo Alípio De Oliveira Leão; Maria Guerreiro. 2008. "Land use effects in groundwater composition of an alluvial aquifer (Trussu River, Brazil) by multivariate techniques." Environmental Research 106, no. 2: 170-177.