Sir David Attenborough highlighted the "terrible plight of our wonderful planet" in a message delivered at the National Television Awards.
The 100-year-old broadcaster, who celebrated his landmark birthday earlier this year, secured the TV presenter prize, having been shortlisted against Alison Hammond, Ant and Dec, Claudia Winkleman and Stacey Solomon.
Although Sir David was unable to attend the ceremony in person, a speech was read out on his behalf.
He said: "I hope this award is a response to the part television has played in growing recognition, not only for the terrible plight our wonderful planet is in as a result of human activity but also of the fact we now have a pressing responsibility to do what we can to protect and conserve it.
"I am honoured indeed. We are increasingly aware that if we are to repair the planet we need major national and international initiatives which certainly require our support, but it is also possible to make small differences in our own spaces and neighbourhoods.
"If enough small differences are made they do add up to doing something significant, while also providing spaces that we do enjoy being in and nurturing.
"Humanity has always needed the natural world for all the practicalities of life and for our mental wellbeing. Now the natural world needs us too. Surely we must not ignore that simple fact."
The naturalist earned two NTA nominations this year, with his documentary Secret Garden featuring in the factual entertainment category. However, that prize was awarded to Gogglebox.
Sir David launched his presenting career with Zoo Quest in 1954, subsequently fronting celebrated series such as The Life Collection, Natural World, Wildlife on One, the Planet Earth franchise, The Blue Planet and Frozen Planet.
The major winners at this year’s National Television Awards included The Celebrity Traitors, Clarkson’s Farm, This Morning and Strictly Come Dancing.
