Distribution of molecular gas tracers towards the surveyed massive clumps. Upper panel: integrated intensity maps of multiple molecular lines towards clumps MM2, MM3 and C. Lower panel: Integrated intensity maps of multiple molecular lines towards clump F1 and F2. For both panels, the velocity range for integration for both regions is [80, 100] km s⁻¹. Before generating the integrated intensity maps, all channels with intensity <0.1 K (2σ) are masked.