For the first time, we propose a diatom-based biomonitoring index (BDIAR) for Algerian Rivers. BDIAR is based on water conductivity and diatom autecological profiles. Our study was conducted along the Coastal Central Constantine watershed, from which 78 samples of diatoms and water were collected. Weighted averaging method was used to determine the diatom autecological parameters (optimum and tolerance), estimated for157 diatom species for the first time in our country. There was a significant positive correlation between measured and expected conductivity values of sampling sites based on their diatom composition (r² = 0.64, P = 0.0001). Linear regression statistics revealed a strong correlation between BDIAR and conductivity (Pearson correlation P = 0.0001). Two similar methods (the Index for Soda Pans DISP and Carayon Index) albeit useful for inferring conductivity values were less accurate (P = 0.08 and 0.03 respectively). χ² and κ statistics demonstrated that using our metric yields a correct site classification in water conductivity classes. The BDIAR is not limited to Algerian streams; it can be applied in biomonitoring programs for all freshwater systems with similar ecological conditions after the reference status determined. This adaptability enhances its potential for widespread use in monitoring and managing water quality across various regions.

我们首次为阿尔及利亚河流提出基于硅藻的生物监测指数（BDIAR）。BDIAR 基于水电导率和硅藻自生态学特征。我们的研究是沿着康斯坦丁中部沿海流域进行的，从中收集了 78 个硅藻和水样本。采用加权平均法确定了硅藻的自生态参数（最适值和耐受性），在国内首次对157种硅藻进行了估算。根据硅藻成分，采样点的测量电导率值和预期电导率之间存在显着的正相关性（r ²  = 0.64，P  = 0.0001）。线性回归统计显示 BDIAR 与电导率之间存在很强的相关性（Pearson 相关性P  = 0.0001）。两种类似的方法（苏打水盘 DISP 指数和 Carayon 指数）虽然可用于推断电导率值，但不太准确（P 分别为 0.08 和 0.03）。χ ²和κ统计数据表明，使用我们的指标可以在水电导率类别中产生正确的位点分类。BDIAR 不仅限于阿尔及利亚流；参考状态确定后，可应用于所有具有相似生态条件的淡水系统的生物监测项目。这种适应性增强了其广泛用于各地区水质监测和管理的潜力。