Sangodkar Nitisha, Gonsalves Maria Judith, Nazareth Delcy R
Aqua-Geomicrobiology Laboratory, Biological Oceanography Division, CSIR-National Institute of Oceanography, Dona Paula, Goa, 403 004, India.
School of Earth, Ocean and Atmospheric Sciences, Goa University, Taleigao Plateau, Goa, 403 001, India.
Microb Ecol. 2023 Jan;85(1):61-75. doi: 10.1007/s00248-021-01942-1. Epub 2022 Jan 4.
Cold seeps are characterized by typical endemic communities with associated microorganisms that depend on sulfide, methane, reduced nitrogenous compounds, and metals as electron donors for their survival through chemosynthesis. The discovery of an active cold seep site in January 2018 in the Krishna-Godavari (K-G) basin of Bay of Bengal was followed by a transit cruise in March 2018 to investigate the distribution and diversity of macrofauna. Further, the ambient sediment and pore water biochemistry were estimated to understand its relationship with macrofauna and the microbial associates of the sediment. Samples were collected at a water depth of around 1750 m at 3 stations: SP1, SP2, and SP3, using the box corer. The benthic fauna at the sites consisted mainly of Bivalvia, shrimps of Caridea family, Gastropoda species, Malacostraca species, Polychaeta, and few species of Echinoidea, Ophiuroidea, and Echiura. A total of 2313 macrofaunal individuals belonging to 8 classes, 18 families, and 20 species were identified from all the three stations. The communities were diverse at these sites with an average Shannon diversity index of 1.64 and are closely related to the lineages previously studied in ecologically similar environments. Most of the macrofauna were found to be filter feeders preferring a low organic carbon environment. Relict vesicomyid clams at the present study site suggest the succession from vesicomyids to the present composition of bivalve mussels and siboglinid worms. The microbial associates in the sediment significantly correlated with methane and hydrogen sulfide concentrations. The study suggests that the K-G basin cold seep serves as a conducive environment for the flourishing of benthic communities and therefore can support a rich biodiversity.
冷泉以典型的特有群落为特征，这些群落伴有微生物，它们依靠硫化物、甲烷、还原态含氮化合物和金属作为电子供体，通过化学合成来维持生存。2018年1月在孟加拉湾克里希纳-戈达瓦里（K-G）盆地发现了一个活跃的冷泉点，随后于2018年3月进行了一次考察航行，以研究大型底栖动物的分布和多样性。此外，还对周围沉积物和孔隙水的生物化学性质进行了评估，以了解其与大型底栖动物以及沉积物中微生物群落的关系。使用箱式采泥器在3个站点（SP1、SP2和SP3）约1750米的水深采集样本。这些站点的底栖动物主要由双壳纲、褐虾科虾类、腹足纲物种、软甲纲物种、多毛纲，以及少数海胆纲、蛇尾纲和螠虫动物门物种组成。从所有三个站点共鉴定出2313个大型底栖动物个体，分属8个纲、18个科和20个物种。这些站点的群落具有多样性，平均香农多样性指数为1.64，并且与先前在生态相似环境中研究的谱系密切相关。发现大多数大型底栖动物是滤食性动物，偏好低有机碳环境。本研究站点的残留泡螺表明了从泡螺到目前双壳贻贝和西伯加虫类蠕虫组成的演替过程。沉积物中的微生物群落与甲烷和硫化氢浓度显著相关。该研究表明，K-G盆地冷泉为底栖群落的繁荣提供了有利环境，因此能够支持丰富的生物多样性。
