Diversidad y abundancia de macroinvertebrados marinos en la zona intermareal rocoso de Punta Blanca y Barbasquillo, Manta-Ecuador.

Abstract

Marine macroinvertebrates play a fundamental role in the functioning of ecosystems. However, in Ecuador they have been little studied. Therefore, the objective of this work was to determine the abundance and diversity of macroinvertebrates in the rocky intertidal zones of Punta Blanca and Barbasquillo. The samplings were carried out from November 16, 2021, to October 15, 2022, at the scheduled time for low tide by the INOCAR tide table using the quadrant method. In addition, conductivity, salinity, temperature and total dissolved solids measurements were made. According to the Shannon index, the diversity in Punta Blanca ranged between 1.10 and 1.51 with an average of 1.21 ± 0.15, while in Barbasquillo the diversity fluctuated between 0.84 and 1.30 with an average of 0.99 ± 0.13, the diversity being significantly higher. in Punta Blanca (t = -3.6617, df = 18, p = 0.001785). Similarly, the relative abundance was significantly higher in Punta Blanca ( 𝜒2 = 208.29, df = 1, p < 2.2 x 10-16). No differences were found between the means of the parameters measured in situ between both areas and no significant correlations were found between the parameters measured in situ with the abundance and diversity of both areas. The models that best fit the data were the Geometric and the Log-normal for Punta Blanca and Barbasquillo, respectively. It is possible that the differences in the diversity and abundance of both areas in this study are due to several factors: natural and anthropogenic disturbances, and methodological errors that may have been made during the course of the study. However, long-term studies are needed to reach deeper conclusions.