The river health of Alista River based on macroinvertebrates communities at Selorejo Village Dau Subdistrict Malang Regency

Abstract

The Alista River is one of the rivers in the upstream Brantas watershed which has relatively natural conditions, but currently there are agricultural activities on the riverbank. The aim of this study was to analyze the health status in Alista River based on the macroinvertebrate communities. This study uses a survey method. Sampling was carried out at 5 stations based on different land use. Sampling of macroinvertebrates used the kicking technique with a hand net with a mesh size of 500 μm in a 10 meter long riffle area. Data analysis used the value of BMWP index (Biological Monitoring Working Party) and the ASPT (Average Score Per Taxon). The results of the identification of macroinvertebrates found were 38 families for instance Glossossomatidae, Lepidosmatidae, and Richardsonianidae. The families belong to 10 orders and 3 classes. The lowest family is 11 families at station 5 (citrus and bamboo gardens). The highest families are 29 families at station 3 (citrus gardens and forests). The results show BMWP-ASPT score ranged from 6.3–4.3 indicating excellent to moderately poor health status. Stations with excellent categories, namely stations 1,2,3,4. Station land use 1,2,3 secondary forest before tourism was discovered including Glossosomatidae. Station 4′s land use is in the form of a tourism location and Lumbriculidae has been found. Stations in the moderately poor category, namely station 5 which is located after tourism sites (citrus gardens and settlements) were found Richardsonianidae.