What does it mean to sing three songs by the long apes in Wuxia, Badong, Three Gorges?

The Three Gorges of the Yangtze River has steep mountains and gloomy scenery, and the shrill cries of apes often make travelers homesick.

Source: The Three Gorges in Daoyuan, North Wei Li.

Selected paragraph:

At the beginning of every sunny day, the frost shines, the forest is cold and sad, and there are often high apes whistling, which leads to sadness, the empty valley echoes, and the sadness turns to leisurely. So the fisherman sang: "The Wuxia Gorge in the Three Gorges of Badong is long, and the apes cry three times, and tears are spilled on their skirts."

Translation:

Every morning when I go to Chuqing or first frost, the Woods and mountains are cool and quiet. There are often high apes singing, and the sound is long and continuous, which is very sad and sad. There is an echo of the ape singing in the empty valley, which is mournful and tactfully lingering for a long time. Therefore, the "Three Gorges Fishing Song" sings: "The Three Gorges of the Yangtze River has steep mountains and gloomy scenery, and the shrill ape sounds often remind travelers of homesickness."

Text interpretation

Under the conditions of ancient times, fishermen or pedestrians passing by boat would be involuntarily afraid of the surrounding environment. Although "the shipwreck crossed Qian Fan", they are always ready to pay the price of their lives. This is the subjective emotion inside.

As for the external objective reality, in addition to seeing the beach is dangerous and the mountains are high, it happened that there are many apes here. The whining and turning sounds of apes are like people "catching fire" and "bumping" with uneasy feelings when they are in danger, so when the spark of the soul flashes, they can't help but feel frightened, so they feel sad and have difficulty walking.