Indonesia's nickel ore export ban has driven rapid expansion of smelting and hydrometallurgical processing capacity at the Indonesia Morowali Industrial Park (IMIP), now the world's largest integrated nickel processing complex, on the coast of Central Sulawesi. Whether this industrialization has degraded the adjacent marine environment remains unquantified. We apply Bayesian structural time-series (BSTS) causal inference to a multi-decadal, multi-sensor satellite ocean color record of the diffuse attenuation coefficient at 490 nm, $K_d(490)$, to test for a causal link between IMIP expansion and nearshore turbidity change. A consensus structural breakpoint, a significant posterior causal effect estimated against a Banda Sea counterfactual, and a distribution-free placebo rank test collectively establish that coastal water clarity deteriorated after the transition from initial nickel pig iron production to hyper-expansion of high-pressure acid leaching facilities for battery-grade nickel. Satellite-derived land cover analysis independently corroborates this timing, showing substantial built-area growth and concurrent tree cover loss within the IMIP footprint. The resulting euphotic zone shoaling occurs in oligotrophic waters supporting high marine biodiversity, where even moderate optical degradation may impair coral photosynthesis and compress depth-dependent reef habitat. These findings quantify a marine environmental cost absent from Indonesia's mineral downstreaming policy discourse and demonstrate a transferable, satellite-based quasi-experimental framework for causal impact assessment at coastal industrial sites in data-limited tropical settings.

翻译：印度尼西亚的镍矿出口禁令推动了位于中苏拉威西海岸的印度尼西亚莫罗瓦利工业园（IMIP）冶炼和湿法冶金加工能力的快速扩张，该园区现已成为全球最大的综合性镍加工基地。然而，这种工业化进程是否已对邻近的海洋环境造成破坏，目前尚未得到量化评估。本研究将贝叶斯结构时间序列（BSTS）因果推断方法应用于多年代、多传感器的卫星海洋水色数据——即490 nm波段漫衰减系数$K_d(490)$的记录——以检验IMIP扩张与近岸水体浊度变化之间的因果关系。通过识别一致的结构断点、基于班达海反事实情景估计出的显著后验因果效应，以及无分布假设的安慰剂排序检验，我们共同证实：在从初始的镍铁生产转向电池级镍高压酸浸设施的超速扩张阶段后，沿海水体透明度显著下降。卫星反演的土地覆盖分析独立印证了这一时间节点，显示IMIP范围内建筑区域大幅增长，同时植被覆盖减少。由此导致的光合作用带变浅现象发生在支持高海洋生物多样性的寡营养水域中，即使中等程度的光学退化也可能损害珊瑚的光合作用，并压缩依赖深度的珊瑚礁生境。这些研究结果量化了印度尼西亚矿产下游化政策讨论中缺失的海洋环境成本，并展示了一种可迁移的、基于卫星的准实验框架，可用于在数据有限的热带沿海工业区进行因果影响评估。