What is the function of dashes in the poem I love this land? Ai Qing's poem-Later I died.

After a big turning point and a dash, "then I died, and even my feathers rotted in the ground." This makes my body fertile, so there is a strong contrast between after my death and before my death. In this strong contrast, the bird's persistent love for the land is that the poet expresses his dependence on the land and his attachment to the motherland through the decay of his feathers after his death.