This study presents how human-altered hydrographical settings (flow restrictions) impacts the natural distribution and community structure of copepods in the Kochi Backwaters (KBW), the largest monsoonal estuary along the southwest coast of India. This study is primarily based on an extensive seasonal sampling in the KBW and their comparison with a historical data set. Thannermukkom Barrage (TB) was built in the southern section of the KBW in the 1970s to prevent saline water intrusion to the upstream during the non-monsoon periods. Thirteen locations (1–4 in the downstream, 5–9 in the midstream, and 10–13 in the upstream) were sampled in this study over the entire stretch of the KBW during the Pre-Southwest Monsoon (PRM), Southwest Monsoon (SWM), and Post-Southwest Monsoon (PSWM). The overall effect of TB in the KBW is a seaward push of mesohaline conditions during all seasons with varying intensities. In response to the seaward push of mesohaline conditions, copepods Acartiella keralensis, Acartia plumosa, Acartia sp., Pseudodiaptomus annandalei, Pseudodiaptomus serricaudatus, Euterpina acutifrons and Oithona brevicornis showed a corresponding spatial shift for their highest abundance and diversity from midstream during PRM to the downstream during the SWM/PSWM. Multivariate and IndVal analysis demarcated many indicator species of copepods of different hydrographical settings in the KBW. A comparison with the historical data set showed that there is an apparent long-term change in hydrography, copepod composition and community structure in the upstream of the KBW due to TB.

这项研究提出了人类改变的水文环境（流量限制）如何影响印度西南沿海最大的季风河口高知死水（KBW）中co足类的自然分布和群落结构。这项研究主要基于KBW的大量季节性抽样，并将其与历史数据集进行比较。Thannermukkom弹幕（TB）建于1970年代，位于KBW的南部，目的是防止非季风期盐水侵入上游。在这项研究中，在西南季风前（PRM），西南季风（PRM）的整个KBW期间，采样了13个位置（下游1-4，中游5-9，上游10-13）（ SWM）和西南西南季风（PSWM）。结核病在KBW中的总体作用是在所有季节以不同强度向海推动中盐度条件。响应中海盐条件向海的推动，co足类Acartiella keralensis，纺锤plumosa，纺锤属，Pseudodiaptomus白虾，Pseudodiaptomus serricaudatus，Euterpina acutifrons和长腹剑水蚤brevicornis显示相应的空间用于从中游它们的最高丰度和多样性PRM期间对下游的SWM / PSWM期间移位。多元和IndVal分析在KBW中划定了许多不同水文环境的co足类的指示物种。与历史数据集的比较表明，由于结核病，KBW上游的水文学，co足类动物的组成和群落结构存在明显的长期变化。