Earth and Life Institute (ELI), Université catholique de Louvain, Croix du Sud 2, 1348, Louvain-la-Neuve, Belgium.
Institute of Mechanics, Materials and Civil Engineering (IMMC), Université catholique de Louvain, Avenue Georges Lemaître 4-6, 1348, Louvain-la-Neuve, Belgium.
Sci Rep. 2023 Jun 9;13(1):9414. doi: 10.1038/s41598-023-36158-5.
Estimating connectivity between coral reefs is essential to inform reef conservation and restoration. Given the vastness of coral reef ecosystems, connectivity can only be simulated with biophysical models whose spatial resolution is often coarser than the reef scale. Here, we assess the impact of biophysical models resolution on connectivity estimates by comparing the outputs of five different setups of the same model with resolutions ranging from 250 m to 4 km. We show that increasing the model resolution around reefs yields more complex and less directional dispersal patterns. With a fine-resolution model, connectivity graphs have more connections but of weaker strength. The resulting community structure therefore shows larger clusters of well-connected reefs. Virtual larvae also tend to stay longer close to their source reef with a fine-resolution model, leading to an increased local retention and self-recruitment for species with a short pre-competency period. Overall, only about half of the reefs with the largest connectivity indicator values are similar for the finest and coarsest resolution models. Our results suggest that reef management recommendations should only be made at scales coarser than the model resolution. Reef-scale recommendations can hence only be made with models not exceeding about 500 m resolution.
评估珊瑚礁之间的连通性对于珊瑚礁保护和恢复至关重要。鉴于珊瑚礁生态系统的广阔性，连通性只能通过生物物理模型来模拟，而这些模型的空间分辨率通常比珊瑚礁尺度更粗糙。在这里，我们通过比较同一模型的五个不同分辨率设置（从 250 米到 4 公里）的输出，评估了生物物理模型分辨率对连通性估计的影响。我们表明，增加珊瑚礁周围模型的分辨率会产生更复杂和方向更不明显的扩散模式。在精细分辨率模型中，连通性图具有更多但强度较弱的连接。因此，由此产生的群落结构显示出更大的、连接良好的珊瑚礁集群。具有精细分辨率模型时，虚拟幼虫也往往会在其来源珊瑚礁附近停留更长时间，从而导致具有短前竞争期的物种的本地保留和自我补充增加。总体而言，只有大约一半的具有最大连通性指标值的珊瑚礁在最精细和最粗糙的分辨率模型中是相似的。我们的结果表明，珊瑚礁管理建议只能在大于模型分辨率的尺度上做出。因此，只能使用不超过约 500 米分辨率的模型来制定珊瑚礁尺度的建议。
