Adkins succeeded Lee Bowyer on a two-and-a-half year deal in March and was tasked with beginning to realise owner Thomas Sandgaard’s grand vision of returning the club to the Premier League and European football within a decade.
But with promotion to the Championship the target for this season, the Addicks have won just two of their opening 13 matches and are in the bottom three following back-to-back defeats to Lincoln and Accrington Stanley.
Jackson, who will be assisted by another former Charlton player in Jason Euell, will take training this morning and address the media this afternoon ahead of the trip to the Stadium of Light.
The 39-year-old, who was also Bowyer’s assistant, was considered for the permanent job before Adkins was appointed and could be in the frame again, with Sandgaard having previously said he wants a "visionary" coach to modernise the south London club.
Jackson won his one game as caretaker in early March, when the Addicks beat Bristol Rovers 3-2 at the Valley.
In a statement confirming Adkins’s departure, Sandgaard said: “Nigel joined us at the end of last season and had an immediate impact, as we finished the season well, just missing out on a play-off place on goal difference. Unfortunately, we haven’t been able to carry that form into this season.
“I’d like to thank Nigel for his hard work, positivity and continued professionalism during his time at the club. We are all disappointed that it hasn’t worked out this season and we wish him the very best for the future.”
Speaking to Standard Sport earlier this month, Sandgaard blamed their poor start on the number of new signings over the summer but said he believed Adkins had all the resources to make a success of the campaign.
"A lot of it has to do with how many new players we brought in," said the Dane. "If you look at the 12 players we ended up signing, most of them fit a new, much more fluid playing style rather than the long balls. It’s taken a while to click.
"The team’s got all the raw materials now. With that, he [Adkins] should be able to get results. Naturally it’s been difficult because it’s the first year and they’re not used to playing together."