Bioecology of macrobenthic communities in the microtidal monsoonal Kodungallur–Azhikode Estuary, southwest coast of India

Abstract

A comprehensive study of the macrobenthic communities in the Kodungallur–Azhikode Estuary (KAE) was conducted during 2009–2011 period. A total of 18,846 organisms were collected, with 60% being malacostracans, followed by polychaetes (20%), molluscs (9%) and ‘others’ group (11%). A total of 79 species in 71 genera belonging to 49 families were identified, with 33 spp. being polychaetes, 26 spp. being malacostracans, 11 spp. being molluscs and 9 spp. being in the ‘others’ group. A single species of opportunistic amphipod (Americorophium triaeonyx) comprised more than 62.05% of the total numerical abundance of macrobenthos. The other dominant species were Obelia bidentata, Arcuatula senhousia, Cirolana fluviatilis, Prionospio cirrifera and Capitella sp. Canonical correspondence analysis (CCA) results indicated environmental parameters such as water column salinity, turbidity, sediment Eh, substratum type, chlorophyll‐a concentration, depth and organic matter in sediment were the significant factors influencing the distribution of macrobenthic species in the KAE. The present study provides baseline information for future KAE benthic studies.

Stable isotopic signatures of sediment carbon and nitrogen sources and its relation to benthic meiofaunal distribution in the Arctic Kongsfjord

“…Some of the environmental factors are also known to induce the large spatial changes in the community composition of the meiofauna in the Arctic fjords (Gulliksen et al, 1985;Holte et al, 1996;Holte & Gulliksen, 1998;Kendall, 1994). The local environmental conditions like presence/absence of ice, exposure to waves, sediment composition and resource availability are considered important to influence the species assemblages (Jayachandran & Bijoy Nandan, 2012;Jayachandran et al, 2019;Szymelfenig et al, 1995;Urban-Malinga et al, 2004). Important aspects influencing the distribution of meiofauna in Kongsfjord include the lack of sediment stability and permanent mineral sedimentation processes (Giere, 1993;Urban-Malinga et al, 2004).…”