There is no official form. A convincing letter of 2 or 3 pages in which the nominator describes how the nominated practitioners bring transdisciplinary science into practice is required.
No, you can only nominate others.
No, this award is not for research proposals, but recognizes practitioners on their past accomplishments.
No, this award is to recognize practitioners. Academics can be nominated, but for their activities as a practitioner, not their scientific contributions.
Please write and submit an essay in which you describe the accomplishments of the nominated person or organization. You may look at essays written about past winners of the award for examples. The winning essays are typically drafts of what will become the article for Ecology and Society.