Benthic macroinvertebrates community to response environmental factors in a crater lake (Case study: Lake Menjer, Indonesia)

Abstract Lake Menjer is one of the crater lakes located in highland Central Java, Indonesia, which has received multiple stressors from anthropogenic activities. Benthic macroinvertebrates as a key indicator for water quality were little known there. Thus, this present research aimed to identify benthic macroinvertebrate structures and understand response community Menjer. Samplings conducted twice, week each August October 2019 at five sites. Sampling represented condition dry season, while rainy season. Some groups identified into family others genus level. Water variables measured directly on site, including clarity, pH, dissolved oxygen (DO), conductivity, total solids (TDS), oxidation-reduction potential (ORP). Meanwhile, level nitrate (TN), phosphate (TP), nitrite, chlorophyll-a analyzed separately. A 4312 composed eleven taxa belonging eight families recorded, namely Chironomidae (22.85%), Tubificidae (73.50%), Lumbricullidae (0.68%), Thiariidae (0.21%), Planorbidae (0.45%), Lymnaeidae Unionidae (0.92%), Corbiculidae (1.13%). The number varied between 1 3 station. Mollusk was best-represented group with families. shown predominant abundance both (3879 ind/m2) (2008 ind/m2). Shannon-Wiener index ranged nearly similar two seasons, 0.17 0.91 0.0 October. ANOSIM CAP6 result illustrated that there an insignificant difference (P below 0.05) among sampling sites This mostly homogenous. Bray-Curtis analysis using MVSP shows similarities compositions performed by Canonical Correspondence Analysis nine tended correlate TN, DO, conductivity. other had relationship temperature, TP, chlorophyll-a.