Water level dynamics in the Amazon floodplain

✍ Scribed by Ivan Bergier Tavares Lima; Reinaldo Roberto Rosa; Fernando Manuel Ramos; Evlyn Márcia Leão de Moraes Novo

• Book ID: 104326859
• Publisher: Elsevier Science
• Year: 2003
• Tongue: English
• Weight: 481 KB
• Volume: 26
• Category: Article
• ISSN: 0309-1708
• DOI: 10.1016/s0309-1708(03)00052-6

✦ Synopsis

Nonlinear analysis of Amazonian River systems suggests that water level variability is due to Brownian-like motions B H . Dynamical properties of the water level is probably a response of rainfall and runoff smoothing by the stored water in the floodplain; additional inputs of water results in attenuated perturbations of the water level. This implies that noise is a self-affine fractal with scale invariance, and in accordance with surrogate and correlation dimension analysis, which refused the hypothesis of low dimensional chaos for water level dynamics. Opposing to the chaotic approach, we present a fractal model formed by a periodic signal and a B H process that mimics original water level variability. Dynamical exponents are remarkably similar between real and modeled data when B H influence is about 1% the amplitude of the periodic signal. In comparison to natural systems, a hydroelectric reservoir produces different exponents, due to the control of the water level, as demonstrated for the Tucuru ı ı dam in the Tocantins River. The Amazon floodplain at O Obidos and Curuai exhibits a fortnight cycle most probably due to bore tide influence in the river mouth.