Department of Marine Sciences, Goa University, Taleigao Plateau, Goa, 403 206, India.
Environ Monit Assess. 2019 Jan 7;191(2):54. doi: 10.1007/s10661-018-7172-7.
The formation of harmful algal blooms (HABs) in the marine environment is detrimental to the ecosystem function affecting the sequence of biological events. Hence, the present study is focused on the seasonal distribution of HAB-forming diatoms and dinoflagellates and their ecological interactions in two tropical estuaries, namely Chapora and Sal in the west coast of India. A total of 17 species of diatoms belonging to nine genera and 13 species of dinoflagellates belonging to eight genera were recorded from the present study (monsoon and non-monsoon season). The redundancy analysis (RDA) revealed that the salinity and phosphate concentration influence the distribution of HAB-forming diatoms and dinoflagellates in both the estuaries. Out of 13 species of dinoflagellates observed, six species are known as potentially toxic such as Alexandrium minutum, A. tamarense, A. pseudogonyaulax, Cochlodinium polykrikoides, Prorocentrum micans and Gonyaulax spinifera. Among these estuaries, Sal was represented with a high diversity of toxic species, associated with high phosphate and nitrate content in the water column. Further, the results indicate that the bloom of A. minutum suppressed the growth of other species of diatoms and dinoflagellates, suggesting its possible allelopathic effect.
海洋环境中有害藻类大量繁殖（HABs）会破坏生态系统功能，影响生物事件的发生顺序。因此，本研究专注于印度西海岸两个热带河口（查波拉和萨尔）中形成 HAB 的硅藻和甲藻的季节性分布及其生态相互作用。本研究共记录了 17 种硅藻，属于 9 属，13 种甲藻，属于 8 属（季风和非季风季节）。冗余分析（RDA）表明，盐度和磷酸盐浓度影响两个河口形成 HAB 的硅藻和甲藻的分布。在所观察到的 13 种甲藻中，有 6 种是有毒的，如微小亚历山大藻、塔玛亚历山大藻、拟短沟藻、多甲藻、微小原甲藻和旋沟藻。在这些河口，萨尔的有毒物种多样性较高，与水柱中的高磷酸盐和硝酸盐含量有关。此外，研究结果表明，微小亚历山大藻的爆发抑制了其他硅藻和甲藻的生长，表明其可能具有化感作用。
