Comparative study of the macroinvertebrate assemblages of two urban rivers of Jujuy, Argentina

The present study aimed to know the structure of the assemblages of aquatic macroinvertebrates and the ecological state of two urban rivers of San Salvador de Jujuy (Jujuy province, Argentina). Sampling was performed in the Xibi Xibi and Río Grande rivers during two seasons (dry and wet) in 2021. Six sampling sites were selected (three per river). At each site, physico-chemical parameters were measured and benthic macroinvertebrates were collected. The ordering of sites according to environmental variables was studied using Principal Component Analysis (PCA). The water quality of the basin was evaluated using different biotic indices. Correlation analysis was carried out between the values of the indices and the physico-chemical parameters. NaCl, TDS (total dissolved solids) and electrical conductivity were higher in the sites corresponding to the Río Grande, while the sites sampled in the Xibi Xibi had a higher altitude. The results of the biotic indices were diverse. The IBY-4 (Yungas biotic index) and ASPT (Average score per taxon) are the most appropriate indices to monitor the water quality of the urban rivers of Jujuy.