Most are free-to-use, ie public domain or copyright-free, meaning the words can be copied and sung to at least one tune with no concerns about copyright or performance licensing.
It has been complied in honour of the World Day of Prayer for the Care of Creation (1 September). This event was introduced to the Catholic Church by Pope Francis in 2015, and it was already practised by the Orthodox Church. It
"offers to individual believers and to the community a precious opportunity to renew our personal participation in this vocation as custodians of creation, raising to God our thanks for the marvelous works that He has entrusted to our care, invoking his help for the protection of creation and his mercy for the sins committed against the world in which we live."In the northern hemisphere, this complements the existing Harvest and Creation Time (1 September - 4 October) celebrations that occur around this time.
Hymns about creation vs care for creation
There are many hymns which thank and praise God for creation, and offer insights into the nature of God based on the wonders of the natural world. However most treat the natural world as something to be exploited. A few of the latter are included in the free-use list, because they are so well-known. But in general these list have hymns that focus on repentance for exploiting creation or developing respect and care for the earth. Because of this, the selection of hymns that are still copyright is larger than usual - these sentiments generally aren't included in older hymns.See Hymns for Harvest Festival for suggestions that are specifically about giving thanks for the fruits of the earth.