Rodriguez Iara Diamela, Saravia Leonardo Ariel
Instituto de Ciencias (ICI), Universidad Nacional de General Sarmiento (UNGS) Buenos Aires Argentina.
Centro Austral de Investigaciones Científicas (CADIC-CONICET) Ushuaia Argentina.
Ecol Evol. 2024 Nov 3;14(11):e70389. doi: 10.1002/ece3.70389. eCollection 2024 Nov.
In the West Antarctic Peninsula, global warming has led to severe alterations in community composition, species distribution, and abundance over the last decades. Understanding the complex interplay between structure and stability of marine food webs is crucial for assessing ecosystem resilience, particularly in the context of ongoing environmental changes. In this study, we estimate the interaction strength within the Potter Cove (South Shetland Islands, Antarctica) food web to elucidate the roles of species in its structure and functioning. We use these estimates to calculate food web stability in response to perturbations, conducting sequential extinctions to quantify the importance of individual species based on changes in stability and food web fragmentation. We explore connections between interaction strength and key topological properties of the food web. Our findings reveal an asymmetric distribution of interaction strengths, with a prevalence of weak interactions and a few strong ones. Species exerting greater influence within the food web displayed higher degree and trophic similarity but occupied lower trophic levels and displayed lower omnivory levels (e.g., macroalgae and detritus). Extinction simulations revealed the key role of certain species, particularly amphipods and the black rockcod , as their removal led to significant changes in food web stability and network fragmentation. This study highlights the importance of considering species interaction strengths in assessing the stability of polar marine ecosystems. These insights have crucial implications for guiding monitoring and conservation strategies aimed at preserving the integrity of Antarctic marine ecosystems.
在南极半岛西部，过去几十年里全球变暖导致群落组成、物种分布和丰度发生了严重变化。了解海洋食物网结构与稳定性之间的复杂相互作用对于评估生态系统恢复力至关重要，尤其是在当前环境变化的背景下。在本研究中，我们估算了波特湾（南极南设得兰群岛）食物网内的相互作用强度，以阐明物种在其结构和功能中的作用。我们利用这些估算值来计算食物网对扰动的稳定性，通过连续灭绝来根据稳定性变化和食物网碎片化情况量化单个物种的重要性。我们探索了相互作用强度与食物网关键拓扑特性之间的联系。我们的研究结果揭示了相互作用强度的不对称分布，弱相互作用占主导，同时存在少数强相互作用。在食物网中发挥更大影响的物种具有更高的度和营养相似性，但占据较低的营养级且杂食性水平较低（例如大型藻类和碎屑）。灭绝模拟揭示了某些物种的关键作用，特别是端足类动物和黑石斑鱼，因为它们的移除导致食物网稳定性和网络碎片化发生显著变化。这项研究强调了在评估极地海洋生态系统稳定性时考虑物种相互作用强度的重要性。这些见解对于指导旨在保护南极海洋生态系统完整性的监测和保护策略具有至关重要的意义。
