Watson Maryann S, Dickson Jon, Franken Oscar, Govers Laura L, van der Heide Tjisse, Witte Sterre, Eriksson Britas Klemens
Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, Netherlands.
Royal Netherlands Institute for Sea Research (NIOZ), Coastal Systems, Den Hoorn, Noord Holland, Netherlands.
PLoS One. 2025 Jan 30;20(1):e0317431. doi: 10.1371/journal.pone.0317431. eCollection 2025.
Coastal reefs benefit the survival and growth of mobile organisms by providing shelter and increased food availability. Under increasing pressure from human activities, the coverage of subtidal reefs has decreased along the world's coasts. This decline is motivating efforts to restore these important habitats by re-introducing hard substrates into the coastal zone. However, many such projects use artificial substrates, such as concrete or metal, that are not naturally occurring in the marine environment. We experimentally introduced hard substrates that were either historically common in a soft sediment-dominated ecosystem, or are mimicking these substrates with biodegradable material, and monitored the substrates for mobile species use (fish and invertebrates). Six substrates were tested: cockle shells, rocks of two sizes (cobbles and pebbles), wood, artificial reefs of calcium carbonate with shell fragments, and biodegradable structures based on potato starch. Within one year, fish and prawns were already attracted to all of the introduced substrates. On average, fish were nearly five times as abundant and prawn abundance increased nearly 30-fold on the artificial reefs, compared to the bare sand bottom control. The community composition on the reefs differed significantly from the sand bottom community, but there were no differences between the types of introduced substrates. Interestingly, the substrates attracted reef-associated fish, but also soft-sediment dependent species, such as different species of flatfish and gobies. Our results show that, even over shorter timespans, introductions of hard substrates provide opportunities to support associated mobile communities in degraded soft-sediment systems.
沿海珊瑚礁通过提供庇护所和增加食物供应，有利于活动生物的生存和生长。在人类活动日益增加的压力下，潮下带珊瑚礁的覆盖面积在世界沿海地区有所减少。这种减少促使人们努力通过将硬质基质重新引入沿海地区来恢复这些重要栖息地。然而，许多此类项目使用的是人造基质，如混凝土或金属，这些在海洋环境中并非天然存在。我们通过实验引入了在以软沉积物为主的生态系统中历史上常见的硬质基质，或者用可生物降解材料模拟这些基质，并监测这些基质被活动物种（鱼类和无脊椎动物）利用的情况。测试了六种基质：鸟蛤壳、两种尺寸的岩石（鹅卵石和砾石）、木材、带有贝壳碎片的碳酸钙人工礁，以及基于马铃薯淀粉的可生物降解结构。在一年内，鱼类和对虾就已经被所有引入的基质所吸引。与裸露的沙地对照相比，人工礁上鱼类的平均数量几乎是其五倍，对虾数量增加了近30倍。珊瑚礁上的群落组成与沙地群落有显著差异，但引入的基质类型之间没有差异。有趣的是，这些基质不仅吸引了与珊瑚礁相关的鱼类，还吸引了依赖软沉积物的物种，如不同种类的比目鱼和虾虎鱼。我们的结果表明，即使在较短的时间跨度内，引入硬质基质也为支持退化的软沉积物系统中的相关活动群落提供了机会。
