Centre for Novel Agricultural Products (CNAP), Department of Biology, University of York, Heslington, York YO10 5DD, United Kingdom.
Centre for Marine Sciences, 1 Anguilla Close, University of the West Indies, Mona, Kingston 7, Jamaica.
Sci Total Environ. 2022 Apr 15;817:152761. doi: 10.1016/j.scitotenv.2021.152761. Epub 2022 Jan 8.
Pelagic Sargassum species have been known for centuries in the Sargasso Sea of the North Atlantic Ocean. In 2011, a new area concentrating high biomass of these brown algae started developing in the Tropical Atlantic Ocean. Since then, massive and recurrent Sargassum influxes have been reported in the Caribbean and off the coast of Western Africa. These Sargassum events have a major negative impact on coastal ecosystems and nearshore marine life, and affect socio-economic sectors, including public health, coastal living, tourism, fisheries, and maritime transport. Despite recent advances in the forecasting of Sargassum events, and elucidation of the seaweed composition, many knowledge gaps remain, including morphotype abundance during Sargassum events, drift of the seaweeds in the months prior to stranding, and influence of sample processing methods on biomass biochemical composition. Using seaweeds harvested on the coasts of Jamaica in summer of 2020, we observed that S. fluitans III was the most abundant morphotype at different times and sampling locations. No clear difference in the geographical origin, or provenance, of the Sargassum mats was observed. The majority of Sargassum backtracked from both north and south of Jamaica experienced ambient temperatures of around 27 °C and salinity in the range of 34-36 psu before stranding. We also showed that cheap (sun) compared to expensive (freeze) drying techniques influence the biochemical composition of biomass. Sun-drying increased the proportion of phenolic compounds, but had a deleterious impact on fucoxanthin content and on the quantities of monosaccharides, except for mannitol. Effects on the content of fucose containing sulfated polysaccharides depended on the method used for their extraction, and limited variation was observed in ash, protein, and fatty acid content within most of the sample locations investigated. These observations are important for the storage and transport of the biomass in the context of its valorisation.
马尾藻属海藻在北大西洋马尾藻海中已经存在了几个世纪。2011 年，在热带大西洋开始出现一个新的区域，集中了大量的这些褐藻。从那时起，加勒比海和西非沿海地区就有大量且反复出现的马尾藻涌入。这些马尾藻事件对沿海生态系统和近岸海洋生物产生了重大负面影响，并影响到包括公共卫生、沿海生活、旅游业、渔业和海上运输在内的社会经济部门。尽管最近在马尾藻事件的预测和海藻组成方面取得了进展，但仍存在许多知识空白，包括马尾藻事件期间的形态类型丰度、海藻在搁浅前几个月的漂流情况，以及样本处理方法对生物量生化组成的影响。使用 2020 年夏天在牙买加海岸收获的海藻进行研究，我们观察到 S. fluitans III 是不同时间和采样地点最丰富的形态类型。没有观察到马尾藻垫在地理来源或起源上有明显的差异。来自牙买加北部和南部的大多数马尾藻在搁浅前经历了约 27°C 的环境温度和 34-36 ppt 的盐度。我们还表明，与昂贵（冷冻）干燥技术相比，廉价（日晒）干燥技术会影响生物量的生化组成。日晒增加了酚类化合物的比例，但对岩藻黄素含量和单糖的含量（甘露糖醇除外）产生了有害影响。含岩藻糖的硫酸多糖的含量取决于用于提取它们的方法，在所研究的大多数采样地点中，灰分、蛋白质和脂肪酸含量的变化有限。这些观察结果对于在其增值的背景下储存和运输生物量很重要。
