Why do Muslims say that man holds the earth in trust?

In 2015, there was an Islamic Declaration on Climate Change which was organised by a number of Islamic organisations including Islamic Relief Worldwide, Greenfaith and others. This was presented to the UN and to carry on this work, the organisation Global Muslim Climate Network was set up. Nana Firman, the then co-chair of this organisation said at the time: >Islam teaches us that 'man is simply a steward whilst holding whatever is on earth in trust.' I've read this before - elsewhere. Q. Why is this, is it justified by reference to the Hadith or Qu'ran or both?