Coastal lagoons are subjected to complex abiotic interactions which result to strong spatio-temporal variability of lagoon-inhabiting communities. Sponges are important components of coastal lagoons, yet their temporal variability is poorly understood. Here, we investigated the temporal variability in local distribution area (LDA), abundance (number of patches) and percentage cover of three lagoon-inhabiting sponge species: Neopetrosia chaliniformis, Amphimedon navalis and Spheciospongia vagabunda from Mauritius (Western Indian Ocean), over a 6- to 8-year period (depending on species). The correlations between two known drivers of sponge temporal patterns, sea surface temperature (SST) and chlorophyll a (Chl a) concentration, were also explored. After the survey, the total LDA and percentage cover of N. chaliniformis decreased by 40.2% and 14.6%, respectively, whereas total LDA and percentage cover of S. vagabunda increased by 135.1% and 23.3%, respectively. No significant changes were seen in the total LDA and percentage cover of A. navalis. While the abundance of N. chaliniformis and A. navalis declined over the study period, the abundance of S. vagabunda increased. SST and Chl a concentration were significantly correlated with temporal changes in abundance of all species, although correlations were species-specific. However, no significant correlations were seen between the environmental parameters and changes in sponge percentage cover, except between SST and N. chaliniformis percentage cover. Our results demonstrate that lagoon sponges show species-specific patterns in temporal variability and, while some species may potentially become locally extinct over the next few decades, if trends continue other species may become more abundant or may remain stable.

中文翻译：

---

毛里求斯（西印度洋）热带泻湖海绵的时间变化

沿海泻湖经历了复杂的非生物相互作用，这导致了泻湖栖息地社区的强烈时空变化。海绵是沿海泻湖的重要组成部分，但是它们的时间变异性却鲜为人知。在这里，我们调查了来自毛里求斯（西印度洋）的三种居住在泻湖的海绵物种：新石化油轮藻，Amphimedon navalis和Spheciospongia vagabunda的局部分布区域（LDA），丰度（斑块数）和覆盖率的时间变化。6到8年（取决于物种）。海绵时间模式的两个已知驱动因素，海面温度（SST）和叶绿素a（Chl a）之间的相关性）浓度，也进行了探讨。调查后，总LDA和百分比盖N. chaliniformis分别降低40.2％和14.6％，而总LDA和百分比盖S. vagabunda分别增加135.1％和23.3％。没有发现重大改变的总LDA和百分比的海军航空兵。虽然丰N. chaliniformis和A. navalis拒绝在研究期间，丰S. vagabunda增加。SST和Chl a浓度与所有物种的丰富度随时间的变化显着相关，尽管相关性是特定于物种的。但是，除了SST和猪油状沙门氏菌百分比覆盖率之间，环境参数与海绵百分比覆盖率变化之间没有显着相关性。我们的研究结果表明，泻湖海绵在时间上表现出特定物种的格局，尽管某些物种可能在未来几十年内局部灭绝，但如果趋势继续下去，其他物种可能会变得更加丰富或保持稳定。