How do ascending poets express tragic and desolate artistic conception in their poems? Besides mourning for autumn, what is the poet mourning for?

The poet used this poem "In the strong wind, apes are sobbing, and birds fly home on the clear lake and white sand beach.". Leaves fall like a waterfall, but I watch the long river roll forward "to show the sadness of autumn." In addition to mourning for autumn, the poet also uses scenery to express his feelings of travel and loneliness. In the general idea of homesickness, he added the content of long-term loneliness, joined the feelings of mourning for the autumn disease, and lamented the twilight years of Wan Li's uprooted people, which made his poems more profound.