Musnad Ahmad 33:385

Abu al-Nadr narrated to us, Abu Aqil narrated to us—Abu Aqil’s name is Abdullah ibn Aqil—Hisham ibn Urwah narrated to us, Ubaydullah ibn Abd al-Rahman ibn Rafi narrated to me, from Jabir ibn Abdullah, who said: The Messenger of Allah, peace and blessings of Allah be upon him, said: "Whoever revives dead land, he has a reward in it, and whatever the creatures eat from it, it is for him as charity."