BackgroundNatural M. chilensis populations dominate habitats with a steep environmental gradient, and that are characterized by abrupt changes in salinity and exposure to desiccation. Although these populations are the source of seed supplies for the Chilean mussel culture industry (annual production around 250 thousand Tons), knowledge about natural populations is scarce. Based on video transect recordings, this study carries out research into one of the principal mussel beds and its associated epibenthic community in the Reloncaví Fjord, both along cross-shore and along-shore distribution gradients.ResultsMytiluschilensis was observed between the middle intertidal zone and the upper subtidal zone (between approximately 9 and 26 psu), with a richer associated community towards the subtidal zone and the fjord mouth. The mussel Condition Index (total meat weight/shell length*100) in the intertidal zone was significantly greater than in the subtidal zone, which raises questions about the reproductive contribution of mussels along the intertidal mid-subtidal gradient.ConclusionsSalinity and tidal variations, together with biological interactions, would seem to be key factors for explaining M. chilensis spatial distribution in the Reloncaví fjord, where beds appear to be in a contraction stage, as evidenced by M. chilensis scarcity towards the subtidal zone. The importance of these populations and their persistence in environments with high perturbation frequency, suggests a monitoring program should be implemented that considers both population spatial distribution and the changing environmental conditions.

中文翻译：

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雷隆卡维峡湾智利贻贝床的空间分布模式：相关过程假设

背景自然智利 M. chilensis 种群在具有陡峭环境梯度的栖息地中占主导地位，其特征是盐度的突然变化和暴露于干燥。尽管这些种群是智利贻贝养殖业（年产量约 25 万吨）的种子供应来源，但关于自然种群的知识很少。本研究基于视频断面记录，对 Reloncaví 峡湾的主要贻贝床之一及其相关的底栖生物群落进行了研究，包括跨海岸和沿海岸分布梯度。潮下带（大约在 9 到 26 psu 之间），在潮下带和峡湾口有更丰富的相关社区。潮间带贻贝状况指数（总肉重/壳长*100）明显大于潮下带，这就引发了贻贝在潮间带中潮下梯度的繁殖贡献的问题。结论盐度和潮汐变化与生物相互作用，似乎是解释 M. chilensis 在 Reloncaví 峡湾空间分布的关键因素，那里的床似乎处于收缩阶段，正如 M. chilensis 向潮下带稀缺所证明的那样。这些种群的重要性及其在高扰动频率环境中的持久性表明，应实施一项监测计划，同时考虑种群空间分布和不断变化的环境条件。