Intensive fish farming is a major industry, but the extent of organic matter (OM) and heavy metal pollution by fish farms is debated. This study established in situ reference conditions using geochemical parameters and fossil benthic foraminiferal assemblages in dated sediment cores to identify potential impacts of fish farming in two basins of the inner Øksfjord, Northern Norway. Living (rose Bengal stained) benthic foraminifera were used to assess the present day environmental conditions. The fossil foraminiferal records were compared with the living foraminifera, which in turn were compared with macrofaunal data. Long-term (>100 yrs) sediment core records of the geochemical parameters (TOC₆₃, C/N, δ¹³C_VPDB TOC and heavy metals) and foraminiferal indices (Norwegian Quality Index (fNQI), AZTI’s Marine Biotic Index (fAMBI), fHlog₂, ES₁₀₀) did not indicate an impact from fish farming through time. Long-term changes in foraminiferal absolute abundances and relative abundances of ecological groups (EGs) reflecting organic matter (OM) tolerance suggest that the OM supply slightly increased compared to reference conditions. Relative abundances of Brizalina skagerrakensis and Epistominella vitrea, previously associated with phytodetrital input, suggest a minor increase in primary productivity compared to reference conditions. The Stainforthia group (S. fusiformis and S. feylingi), indicative of OM enrichment, in the living foraminiferal assemblages may indicate a response to fish farming activities, but foraminiferal seasonality could not be excluded as a potential cause. The indices of both fossil and living foraminifera, in addition to the macrofauna showed a good to high Ecological Quality Status (EcoQS) through time and at present. This indicates that environmental conditions have been and still are acceptable.

集约化养鱼是一项主要产业，但养鱼场对有机物（OM）和重金属的污染程度尚存争议。这项研究利用地球化学参数和化石底栖有孔虫组合在陈旧的沉积岩心中建立了原位参考条件，以确定挪威北部Øksfjord内两个盆地鱼类养殖的潜在影响。使用活的（孟加拉红染色）底栖有孔虫来评估当今的环境条件。将化石有孔虫记录与活有孔虫进行比较，然后将其与大型动物资料进行比较。长期（> 100岁）的地球化学参数的沉积物核心记录（TOC ₆₃，C / N，Δ ¹³ Ç _VPDBTOC和重金属）和有孔虫指数（挪威质量指数（fNQI），AZTI的海洋生物指数（fAMBI），fHlog ₂和ES ₁₀₀）并未表明鱼类养殖对时间的影响。有孔虫的绝对丰度和反映有机物（OM）耐受性的生态群体（EG）的相对丰度的长期变化表明，与参考条件相比，OM的供应量略有增加。Brizalina skagerrakensis和Epistominella vitrea的相对丰度，以前与植物碎屑的输入有关，表明与参考条件相比，初级生产力略有提高。该Stainforthia组（S.梭形和S. feylingi）表示有活力的有孔虫组合中的OM富集，可能表明对鱼类养殖活动有反应，但不能排除有孔虫的季节性作为潜在原因。化石和有孔虫的指数以及大型动物区系在整个时间和目前都表现出良好的生态质量状态（EcoQS）。这表明环境条件已经并且仍然可以接受。