ESTUDO DE SEDIMENTOS SUSPENSOS NA ENTRADA DE TOMADA DE ÁGUA DO REGADIO DE CHÓKWE.

Abstract

The objective of this study was to study the suspended sediments at the water intake entrance of the Chókwè irrigation system, where, for the materialization of this objective, a bathymetry was done using topographies, performed as equipment for collecting the net load for calculation the concentration and the estimate of the amount of suspended sediment, the use of a reel for the characteristics of velocity over the depth and width of the outlet and laboratory analyzes were carried out to analyze the physical characteristics and compounds of the suspended sediments, where calcium was measured, sodium, potassium, electrical conductivity, turbidity, pH and temperature. In bathymetry, sedimentary areas are 2.86 m2, 0.41 m2 and 0.30 m2. In the concentration of suspended solids a maximum amount of 737.47 ton / h is obtained. For electrical conductivity the maximum values obtained in mScm-1 at Points I, II and III are 0.490, 0.450 and 0.470. Turbidity showed an increasing increase in periods when the occurrence upstream and a decrease to separate from 1000 NTU to 73.00 NTU. The pH of the waters was greater than 7.00 for all points. The values of sodium, calcium and potassium vary at the three points (I, II and III) from 0.510 to 1.010 mgl-1, 0.540 to 1.070 mgl-1 and 4.550 to 6.190 mgl-1. The average speed at Point I is 0.246 ms-1, at Point II is 0.295 ms-1 and at Point III is 0.341 ms-1, and the results vary depending on the depth of the channel. For data that had a good correlation, their correlation coefficients (r) vary from 0.761 to 0.908 and the determination coefficients (r2) vary from 58% to 83%. The data showing no correlation, its correlation coefficients (r) vary from 0.023 to 0.117 and the determination coefficients (r2) vary from 0% to 2%. Finally, the data showing a weak correlation, its correlation coefficients (r) vary from 0.298 to 0.301 and the determination coefficients (r2) is 9%. In general there is an entry of suspended sediments coming from the river that will not accumulate any main channel and these results can be used in agricultural production systems or in the operation of irrigation in general.