A case study of factors controlling water quality in two warm monomictic tropical reservoirs located in contrasting agricultural watersheds.

Autor: Lopes MC; Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista (UNESP), Programa de Pós-Graduação em Agronomia, Ciência do Solo, Via de Acesso Prof. Paulo Donato Castellane, s/n, Jaboticabal, SP 14884-900, Brazil; Polo Regional Centro Norte, Departamento de Descentralização do Desenvolvimento - APTA, Secretaria de Agricultura e Abastecimento - SAA, Rodovia Washington Luis, Km 371, s/n, Pindorama, SP 15830-000, Brazil; POLUS-Grupo de Política de Uso do Solo, Universidade Estadual Paulista (UNESP), Via de Acesso Prof. Paulo Donato Castellane, s/n, Jaboticabal, SP 14884-900, Brazil., Martins ALM; Polo Regional Centro Norte, Departamento de Descentralização do Desenvolvimento - APTA, Secretaria de Agricultura e Abastecimento - SAA, Rodovia Washington Luis, Km 371, s/n, Pindorama, SP 15830-000, Brazil., Simedo MBL; Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista (UNESP), Programa de Pós-Graduação em Agronomia, Ciência do Solo, Via de Acesso Prof. Paulo Donato Castellane, s/n, Jaboticabal, SP 14884-900, Brazil; POLUS-Grupo de Política de Uso do Solo, Universidade Estadual Paulista (UNESP), Via de Acesso Prof. Paulo Donato Castellane, s/n, Jaboticabal, SP 14884-900, Brazil., Filho MVM; Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista (UNESP), Programa de Pós-Graduação em Agronomia, Ciência do Solo, Via de Acesso Prof. Paulo Donato Castellane, s/n, Jaboticabal, SP 14884-900, Brazil; POLUS-Grupo de Política de Uso do Solo, Universidade Estadual Paulista (UNESP), Via de Acesso Prof. Paulo Donato Castellane, s/n, Jaboticabal, SP 14884-900, Brazil., Costa RCA; Universidade Guarulhos (UNG). Programa de Mestrado em Análise Geoambiental (MAG). Praça Tereza Cristina, 239, 07023-070, Guarulhos, SP, Brazil; POLUS-Grupo de Política de Uso do Solo, Universidade Estadual Paulista (UNESP), Via de Acesso Prof. Paulo Donato Castellane, s/n, Jaboticabal, SP 14884-900, Brazil., do Valle Júnior RF; Instituto Federal do Triângulo Mineiro, Campus de Uberaba, Laboratório de Geoprocessamento, Uberaba, MG 38064-790, Brazil; POLUS-Grupo de Política de Uso do Solo, Universidade Estadual Paulista (UNESP), Via de Acesso Prof. Paulo Donato Castellane, s/n, Jaboticabal, SP 14884-900, Brazil., Rojas NET; Centro Avançado de Pesquisa do Pescado Continental - APTA, Av. Abelardo Menezes, s/n Zona Rural, São José do Rio Preto, SP 15025-620, Brazil., Sanches Fernandes LF; CITAB - Centro de Investigação e Tecnologias Agroambientais e Biológicas, Universidade de Trás-os-Montes e Alto Douro, Ap. 1013, 5001-801 Vila Real, Portugal; POLUS-Grupo de Política de Uso do Solo, Universidade Estadual Paulista (UNESP), Via de Acesso Prof. Paulo Donato Castellane, s/n, Jaboticabal, SP 14884-900, Brazil., Pacheco FAL; CQVR - Centro de Química de Vila Real, Universidade de Trás-os-Montes e Alto Douro, Ap. 1013, 5001-801 Vila Real, Portugal; POLUS-Grupo de Política de Uso do Solo, Universidade Estadual Paulista (UNESP), Via de Acesso Prof. Paulo Donato Castellane, s/n, Jaboticabal, SP 14884-900, Brazil. Electronic address: fpacheco@utad.pt., Pissarra TCT; Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista (UNESP), Programa de Pós-Graduação em Agronomia, Ciência do Solo, Via de Acesso Prof. Paulo Donato Castellane, s/n, Jaboticabal, SP 14884-900, Brazil; POLUS-Grupo de Política de Uso do Solo, Universidade Estadual Paulista (UNESP), Via de Acesso Prof. Paulo Donato Castellane, s/n, Jaboticabal, SP 14884-900, Brazil.
Jazyk: angličtina
Zdroj: The Science of the total environment [Sci Total Environ] 2021 Mar 25; Vol. 762, pp. 144511. Date of Electronic Publication: 2020 Dec 16.
DOI: 10.1016/j.scitotenv.2020.144511
Abstrakt: The integration of internal (e.g., stratification) and external (e.g., pollution) factors on a comprehensive assessment of reservoir water quality determines the success of ecosystem restoration initiatives and aids watershed management. However, integrated analyses are scarcer than studies addressing factors separately. Integration is likely more efficient in studies of small well-characterized (experimental) reservoir watersheds, because the isolation of factor contributions is presumably clearer. But those studies are uncommon. This work describes the water quality of two small 5.5 m-deep reservoirs (MD-Main and VD-Voçoroca dams) located in Pindorama Experimental Center, state of São Paulo, Brazil, considering the interplay between reservoir dimension, seasonal thermal stratification, chemical gradients, erosive rainfall events, presence of natural biofilters, and land uses and landscape patterns around the reservoirs and within the contributing watersheds. The monitoring of agricultural activities and water quality parameters occurred in October 2018-July 2019. A 4 °C thermal stratification occurred in October (difference between surface and bottom water temperature), which decreased until disappearance in January (VD) or April (MD). The longer stratification period of MD was justified by its larger area relative to VD (≈10×). Thermal stratification triggered hypoxia at the bottom of both reservoirs (DO ≈ 1 mg/L), more prolonged and severe in MD. Hypoxia activated Ec and TDS peaks in January likely explained by bottom-sediment nutrient releases, presumably phosphorus. The Ec peak reached 560 μS/cm in MD and 290 μS/cm in VD. The smaller VD peak was probably explained by the action of macrophytes. In March, a 240 NTU turbidity peak occurred in MD, caused by precedent erosive rainfall and the lack of vegetation protection alongside the south border. As expected, the study accomplished clear isolation of factor contributions, verified by Factor and Cluster analyses. Our results can subsidize studies on larger reservoir watersheds requiring restoration, where the isolation of factors is more challenging.
Competing Interests: Declaration of competing interest The authors declare no conflicts of interest. The funders had no role in the design of the study, in the collection, analyses, or interpretation of data, in the writing of the manuscript, or in the decision to publish the results.
(Copyright © 2020 Elsevier B.V. All rights reserved.)
Databáze: MEDLINE
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