Abundance of SiO with H₂ column density in the DR21 filament and ATLASGAL sources (Csengeri et al. 2016) and SFRs (Kim et al. 2023), and R_D(DCO⁺) with the abundance of SiO in the DR21 filament (first and second row, respectively). The third row and fourth row shows the H₂ column density and the dust temperature with R_D(DCO⁺), respectively, where purple shows non-detection of SiO and orange shows the pixels where SiO was detected ≥4σ. The red and blue stars mark the surroundings of DR21 Main and DR21(OH), respectively.