Tom Abell is to captain Somerset in the One-Day Cup next term and continue to skipper the County Championship side.
County champions Essex begin the defence of their title in 2018 against Yorkshire at Headingley on 13 April.
Somerset spinner Jack Leach says he is a better bowler for having gone through the "dark time" of remodelling his action.
Somerset chairman Andy Nash is to step down in January and is to be replaced by committee member Charles Clark.
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Somerset's outgoing director of cricket Matt Maynard reacts to their survival in Division One and their pitch being graded "below average".
Analysis and opinion from the BBC's cricket correspondent.
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