Small, trade-dependent economies often exhibit limited maritime connectivity, yet empirical evidence on the structural configuration of their container systems remains limited. This study analyzes route concentration and node distributions in Mauritania's maritime container system during 2019-2022 using shipment-level data measured in forty-foot equivalent units (FFE). Routes, origin nodes, destination nodes, and industries are represented as FFE-weighted probability distributions, and concentration and divergence metrics are used to assess structural properties. The results show strong corridor concentration across the seven observed routes (HHI = 0.296), with the top three accounting for approximately 84% of total FFE. Node structures differ by direction: imports are associated with a highly concentrated set of destination nodes (HHI = 0.848), while exports originate from only two origin nodes (HHI = 0.567) and are distributed across a large number of destinations (HHI = 0.053). Industry distributions are more concentrated for exports (HHI = 0.352) than for imports (HHI = 0.096), with frozen fish and seafood accounting for more than 53% of export volume. Temporal analysis shows that route concentration remains stable over time (HHI ~ 0.293-0.303), while node distributions exhibit measurable variation, particularly for export destinations (JSD ~ 0.395) and import origins (JSD ~ 0.250).

翻译：小型贸易依赖型经济体通常面临有限的海运连通性，但关于其集装箱系统结构配置的实证证据仍然匮乏。本研究利用以四十英尺标准箱（FFE）为单位的货运层级数据，分析了2019-2022年毛里塔尼亚海运集装箱系统的航线集中度与节点分布。航线、起运节点、目的节点及产业均以FFE加权概率分布呈现，并采用集中度与离散度指标评估其结构特性。结果显示，七条观测航线的通道集中度较高（赫芬达尔指数=0.296），前三名航线约占FFE总量的84%。节点结构呈现方向性差异：进口端的目的节点高度集中（赫芬达尔指数=0.848），而出口端仅有两个起运节点（赫芬达尔指数=0.567），但目的地分布广泛（赫芬达尔指数=0.053）。产业集中度方面，出口端（赫芬达尔指数=0.352）高于进口端（赫芬达尔指数=0.096），其中冷冻鱼及海产品占出口总量的53%以上。时序分析表明，航线集中度随时间保持稳定（赫芬达尔指数约0.293-0.303），而节点分布存在显著波动，尤其出口目的地（詹森-香农散度约0.395）与进口起运地（詹森-香农散度约0.250）的变异程度最为突出。