Colonización de sustratos por macroinvertebrados acuáticos en las aguas de la Quebrada Charquira del municipio de Carmen de Carupa

Abstract

The research was carried out during the month of October 2016, and its main objective was to evaluate the selection of substrates by aquatic macroinvertebrates in two stations of Charquira gorge, in the municipality of Carmen of Carupa; the first station (pasture area) has presented the stone substrate, the second station (Vegetation zone) is characterized by native vegetation and not native in the margin of the creek, the present substrate is fallen leaves; each of the stations is divided by 8 sampling points each 1 meter apart and at each point two substrate types (fallen leaves and stone) were arranged for 16 substrates at each station and a total of 32 substrates; the physicochemical variables of the water were determined and a sampling was carried out with the Surber network at each of the respective sampling points of each station; the collection of the colonization artifacts, the sampling with the network and the respective measurements of the physicochemical parameters were carried out at 1, 3, 5, 7, 13, 19, 25 and 31 days of exposure; we determined both the colonizing species and the species that were sampled with the network, there were significant differences in season 2 with respect to season 1 versus the total number of individuals, the genus Helisoma was the only one that showed selectivity in the fallen leaves substrate. In total, 989 individuals distributed in 7 orders, 8 families and 18 genera, the dominant genus for station 1 was Chironomus with 287 individuals, station 2 was the Tanytarsus genus with 225 individuals, followed by Helisoma with 158 Individuals; The substrate with the highest number of colonizing individuals was fallen leaves; There was no correlation between genders and physicochemical parameters; Dissolved oxygen, phosphorus and ammoniacal nitrogen showed low concentration, which shows that the waters of the ravine are oligotrophic, a slightly acid pH and average of 13 ° C; The conductivity was 66 mV and 51 mV for stations 1 and 2 respectively and turbidity values of 12.2 and 5.8 NTU. The riparian vegetation is important to maintain a heterogeneous community, because this one brings different substrates to the ravine.