Tone is an author’s attitude toward a subject. Mood, on the other hand, is the emotional environment created by the words. I would say that this poem is hopeful, pleading and celebratory. Consider the tone with words such as “through whom the spirit breathes” (line 3) and “You purify the air of eternity, here where I breathe the air of my fathers” (line 8). These are hopeful to me.
There are also some pleading lines such as “In the name of your image, listen to me!” (line 12) and “Now turn your immobile eyes towards your children who/have been called/And who sacrifice their lives like the poor man his last garment” (lines 17-19).
Finally, the tone is also celebratory:
For who else would teach rhythm to the world that has
died of machines and cannons?
For who else should ejaculate the cry of joy, that arouses the dead and the wise in a new dawn?
Say, who else could return the memory of life to men with a torn hope? (lines 22-26)
This seems to be the speaker suggesting a rebirth of Africa, and pride in Africa.
So when the reader reads this poem, he or she might feel a mood of hope or celebration. The speaker’s words create this affect due to their tone.