Looks like you deconstructed a chest or removed your power armour and exceeded your inventory capacity.

Ah, the good ole inventory spill. Well, at least spilled items don't drop onto belts anymore, clogging the entire factory.

Cause: Either..

• You were crafting something with a lot of ingredients, and picked up more ingredients during. Then crafting was canceled and there wasn't enough room for all the ingredients.
• Your inventory capacity was reduced, mostly likely by removing armor with an inventory capacity bonus.

The fix: Either..

• Run over and hit the "pick up item in ground"-key. I think it's F by default.
• Select the items in ground with a deconstruction planner and let bots take care of it. You can create a deconstruction planner and edit it to only whitelist items in ground - It's by far the easiest. If you don't have bots yet, iirc if you run over an item on ground that is marked for deconstruction you pick it up automatically.