Acessibilidade / Reportar erro
Scientific Article • Rev. Ciênc. Agron. 52 (1) • 2021 • https://doi.org/10.5935/1806-6690.20210010   copy

Limnological dynamics in an artificial reservoir and intermittent river in the semi-arid region as a function of land use and occupation1 1 Parte da Tese do primeiro autor a ser apresentada ao Programa de Pós-Graduação em Ecologia e Recursos Naturais, Departamento de Biologia, Universidade Federal do Ceará/UFC

Dinâmica limnológica em reservatório artificial e rio intermitente na região semiárida em função do uso e ocupação do solo

Authorship SCIMAGO INSTITUTIONS RANKINGS

ABSTRACT

Remote sensing coupled with the measurement of physical, chemical and biological variables is an important tool in water resource management. The aim of this study, therefore, was to evaluate the dynamics of the physical, chemical and biological variables of the waters of an intermittent river and an artificial surface reservoir using multivariate analysis and in response to land use and occupation in the hydrographic basin. The study was carried out in the hydrographic basin of the River Cruxati in four study areas (three river areas and one artificial reservoir), with images obtained from the OLI sensor of the Landsat-8 satellite. The limnological variables measured were pH, electrical conductivity, dissolved oxygen, turbidity, nutrients (total nitrogen and total phosphorus) and chlorophyll a. The limnological variables were analysed using Principal Component Analysis - PCA, Tukey's test and Cluster Analysis. Eutrophication of the areas under study was calculated using the Trophic State Index. The PCA allowed three components to be selected that indicated the quality of the surface water, river and artificial reservoir, explaining 88.57% of the total variance. The limnological variables responsible for the grouping were electrical conductivity, dissolved oxygen and turbidity. Land use and occupation has influenced water quality in the stretches of river. Anthropisation has had an influence on the levels of dissolved oxygen, and the presence of agricultural areas has caused an increase in turbidity. However, the most conserved landscape (artificial reservoir) had the highest degree of eutrophication due to the difference in water dynamics between the lentic and lotic environments.

Keywords:
Water quality; Eutrophication; Remote sensing; Multivariate statistical analysis

Universidade Federal do Ceará Av. Mister Hull, 2977 - Bloco 487, Campus do Pici, 60356-000 - Fortaleza - CE - Brasil, Tel.: (55 85) 3366-9702 / 3366-9732, Fax: (55 85) 3366-9417 - Fortaleza - CE - Brazil
E-mail: ccarev@ufc.br
Acompanhe os números deste periódico no seu leitor de RSS