i) births and deaths
16 March 1935: birth of Donald Tosh, script editor in 1965-66, author of "Bell of Doom", fourth episode of the story we now call The Massacre (First Doctor, 1966).
also 16 March 1935: birth of Tristan de Vere Cole, director of The Wheel in Space (Second Doctor, 1968).
16 March 1943: birth of John Leeson, the voice of K9 in Old Who (apart from one season), New Who, the first Sarah Jane spinoff K9 and Company, the more successful Sarah Jane Adventures and let's not forget the Australian K9 series (though I think he himself might like to). He also appeared in person as Dugeen in The Power of Kroll (Fourth Doctor, 1978-79).
ii) broadcast anniversaries
16 March 1968: broadcast of first episode of Fury from the Deep. The Doctor, Jamie and Victoria arrive at an oil refinery where the chief refuses to do anything about the mysterious noises and pressure fluctuations in the pipelines.
16 March 1974: broadcast of fourth episode of Death to the Daleks. The Doctor destroys the City, freeing both Earth astronauts and Daleks; but Galloway has hidden on the Dalek ship, and destroys it as it takes off.
16 March 1982: broadcast of fourth episode of Earthshock. The Cybermen are defeated, but the freighter crashes into prehistoric earth, killing Adric. Last regular appearance of Matthew Waterhouse as Adric.
16 March 1983: broadcast of second episode of The King's Demons, ending Season 20. The Doctor takes control of Kamelion and defeats the Master.
16 March 1984: broadcast of fourth epsiode of The Caves of Androzani. The Doctor rescues Peri as everyone else on Androzani Minor gets blown up or otherwise killed, but is unable to save himself. Last regular appearance of Peter Davison as the Fifth Doctor, and first appearance of Colin Baker as the Sixth Doctor.
16 March 1985: broadcast of second episode of Timelash. The Borad turns out to be mad scientist Megelen, who the Doctor kills twice, returning Herbert to Scotland to become H.G. Wells.
16 March 2007: Lauren has a new English teacher. But who is Mr Logan? Or rather, Mr Logan is Who.