What kind of feelings did this ancient poem express to Wang Wei?

Through the scenery he saw when he went to the fortress, this poem expressed the poet's feelings of loneliness, loneliness, sadness and wandering caused by being excluded.

Go to the frontier to carry out tasks

Wang Wei

Riding a bike to visit the border and passing through Juyan County. Pengpeng also floated out of Korea, and the geese heading north also flew into the sky.

The vast desert is lonely, and the Yellow River sets the yen. When I arrived at the small pass, I met a spy waiting for the knight and told me that Dou Hu was in Yan.