CARACTERÍSTISCAS DA RELAÇÃO CONCENTRAÇÃO DE SEDIMENTO SUSPENSO E VAZÃO EM BACIA RURAL NO MUNICÍPIO DE GUARAPUAVA- PR

Abstract

The main purpose of this work is investigate the relation between concentration of suspended sediment and the water flow through a classification and a quantitative analysis of the diverse hysteresis loops obtained during precipitation events in the Guabiroba river's hydrographic basin located in the rural area of the city of Guarapuava - PR. The features of the obtained hysteresis loops are linked to two origins, the first one is the erosion of the slopes and the second one are the erosion of the river bank and riverbed due the flow. Through this knowledge, the classes of hysteresis loops were studied in accordance to Williams (1989), and the rains' features were calculated through Richardt (1986), what allowed obtain the influence of the features of the precipitation in the fluvio sedimentological rate in the drainage channels. The twenty selected events were classified as follows: as only one event belongs to the hysteretic loop type I (single-valued line); there are six events to the hysteretic loop type II (clockwise loop); there are two events of the hysteretic loop type III (single line - plus loop); there are two events of the hysteretic type IV (counterclockwise) and there are seven events of the hysteretic type V (figure eight).The hysteresis indice _ IH, was obtained according to Lawler et al. (2006), and endorsed the qualitative analysis of the hysteresis loop performed in the twenty events. The correlation coefficient (R²), presents two significant results, the first one was the number 12 event, with R² = 0,99 of correlation Css vs. Q; and the second one was the number 6 event, with R² = 0,0, which means no correlation between Css and Q. The influence of others factors, like the characteristics of the precipitations, may have triggered new areas of sources of sediments, as consequence modified the relation Css Vs. Q, with more or less sediment moved to the drainage channel.