Map layer road, night level LNight

Outside the agglomerations, major roads (highways, federal and state roads) with a traffic volume of over 3 million vehicles per year are to be mapped. In addition, other noise-relevant roads such as municipal roads or roads with lower traffic volumes are mapped in the agglomerations.在城市群（agglomerations）以外区域，需对年车流量超过300万辆的主要道路（高速公路、联邦公路及州级公路）开展测绘。此外，在城市群内部，还需测绘其他与噪声相关的道路，例如市政道路或车流量较低的道路。