With permission granted to record both before and after the operation, I set up my gear and captured a large number of dawn choruses to very strict protocol and calibrated recordings, because I wanted a really good baseline.
我得到了准许， 可在那儿伐木前和伐木前后录音。 我架好设备，录下大量清晨的鸟叫声 录音都有精确的标准，且标有刻度 因为我想得到真正高质量的基线