Comparison of sediment rating curves and sediment yield in subbasins of the Itacaiúnas River Watershed, Eastern Amazon

Abstract

Understanding the hydrosedimentological dynamics of tropical rivers is a challenge in the Amazon due to its remote and difficult-to-access areas. This study was based on data collected from 16 hydrosedimentological control sections in the 6 subbasins that make up the Itacaiúnas River Watershed (IRW), with 4 annual campaigns (high water levels, rising water levels, falling water levels, low water levels) between 2015 and 2019, with the aim of constructing and comparing sediment rating curves and sediment yield. The data at the mouth of the IRW revealed that the rainy season is responsible for 93% of liquid discharges (Q) with an average of 1460.88 m3/s and for 98% of suspended sediment discharges (SSQ) with an average of 5864.15 tons/day. Suspended sediment concentrations (SSCs) are low to moderate (50 to 150 mg/l). The curves encompassing all the data showed R2 values (0.92 to 0.99) greater than the curves with only the values of the rainy or dry season, indicating a good fit of the power equation to the SSQ and Q data for all sections studied. Higher values of coefficients a and b show areas of greater sediment production and deforestation, as well as areas with new sources of sediment and preserved forest.

Lightning under Different Land Use and Cover, and the Influence of Topography in the Carajás Mineral Province, Eastern Amazon

“…The basin has 1/3 of its area protected (conservation units and indigenous lands), which is indicative of the environmental significance of the region for biodiversity conservation [15]. Deforested areas correspond to approximately half of the basin area and are predominantly used for pastures.…”

“…BrasilDAT uses the time-of-arrival (TOA) method to detect intracloud pulses and cloud-to-ground strokes and operates in the frequency range between 1 Hz and 12 MHz. This method employs three or more sensors to determine the moment the electromagnetic radiation The basin has 1/3 of its area protected (conservation units and indigenous lands), which is indicative of the environmental significance of the region for biodiversity conservation [15]. Deforested areas correspond to approximately half of the basin area and are predominantly used for pastures.…”

Uso de radar meteorológico para a avaliação das variáveis polarimétricas associadas a descargas atmosféricas no Leste da Amazônia

“…A região apresenta em torno de 1/3 de áreas protegidas (unidades de conservação e terras indígenas), fato este que é um indicativo da relevância ambiental da região para a proteção da biodiversidade (SILVA et al, 2021). As áreas de desflorestamento correspondem, em torno da metade da área da Bacia e são predominantemente utilizadas para pastagens.…”